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Cisneros WJ, Soliman SHA, Walter M, Simons LM, Cornish D, De Fabritiis S, Halle AW, Kim EY, Wolinsky SM, Lorenzo-Redondo R, Shilatifard A, Hultquist JF. Release of P-TEFb from the Super Elongation Complex promotes HIV-1 latency reversal. PLoS Pathog 2024; 20:e1012083. [PMID: 39259751 PMCID: PMC11419360 DOI: 10.1371/journal.ppat.1012083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2024] [Revised: 09/23/2024] [Accepted: 08/27/2024] [Indexed: 09/13/2024] Open
Abstract
The persistence of HIV-1 in long-lived latent reservoirs during suppressive antiretroviral therapy (ART) remains one of the principal barriers to a functional cure. Blocks to transcriptional elongation play a central role in maintaining the latent state, and several latency reversal strategies focus on the release of positive transcription elongation factor b (P-TEFb) from sequestration by negative regulatory complexes, such as the 7SK complex and BRD4. Another major cellular reservoir of P-TEFb is in Super Elongation Complexes (SECs), which play broad regulatory roles in host gene expression. Still, it is unknown if the release of P-TEFb from SECs is a viable latency reversal strategy. Here, we demonstrate that the SEC is not required for HIV-1 replication in primary CD4+ T cells and that a small molecular inhibitor of the P-TEFb/SEC interaction (termed KL-2) increases viral transcription. KL-2 acts synergistically with other latency reversing agents (LRAs) to reactivate viral transcription in several cell line models of latency in a manner that is, at least in part, dependent on the viral Tat protein. Finally, we demonstrate that KL-2 enhances viral reactivation in peripheral blood mononuclear cells (PBMCs) from people living with HIV (PLWH) on suppressive ART, most notably in combination with inhibitor of apoptosis protein antagonists (IAPi). Taken together, these results suggest that the release of P-TEFb from cellular SECs may be a novel route for HIV-1 latency reactivation.
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Affiliation(s)
- William J. Cisneros
- Division of Infectious Diseases, Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States of America
- Center for Pathogen Genomics and Microbial Evolution, Havey Institute for Global Health, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States of America
| | - Shimaa H. A. Soliman
- Simpson Querrey Institute for Epigenetics, Department of Biochemistry and Molecular Genetics Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States of America
| | - Miriam Walter
- Division of Infectious Diseases, Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States of America
| | - Lacy M. Simons
- Division of Infectious Diseases, Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States of America
- Center for Pathogen Genomics and Microbial Evolution, Havey Institute for Global Health, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States of America
| | - Daphne Cornish
- Division of Infectious Diseases, Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States of America
- Center for Pathogen Genomics and Microbial Evolution, Havey Institute for Global Health, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States of America
| | - Simone De Fabritiis
- Simpson Querrey Institute for Epigenetics, Department of Biochemistry and Molecular Genetics Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States of America
| | - Ariel W. Halle
- Division of Infectious Diseases, Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States of America
- Center for Pathogen Genomics and Microbial Evolution, Havey Institute for Global Health, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States of America
| | - Eun-Young Kim
- Division of Infectious Diseases, Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States of America
| | - Steven M. Wolinsky
- Division of Infectious Diseases, Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States of America
| | - Ramon Lorenzo-Redondo
- Division of Infectious Diseases, Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States of America
- Center for Pathogen Genomics and Microbial Evolution, Havey Institute for Global Health, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States of America
| | - Ali Shilatifard
- Simpson Querrey Institute for Epigenetics, Department of Biochemistry and Molecular Genetics Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States of America
| | - Judd F. Hultquist
- Division of Infectious Diseases, Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States of America
- Center for Pathogen Genomics and Microbial Evolution, Havey Institute for Global Health, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States of America
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2
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Bentley DL. Multiple Forms and Functions of Premature Termination by RNA Polymerase II. J Mol Biol 2024:168743. [PMID: 39127140 DOI: 10.1016/j.jmb.2024.168743] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2024] [Revised: 08/05/2024] [Accepted: 08/06/2024] [Indexed: 08/12/2024]
Abstract
Eukaryotic genomes are widely transcribed by RNA polymerase II (pol II) both within genes and in intergenic regions. POL II elongation complexes comprising the polymerase, the DNA template and nascent RNA transcript must be extremely processive in order to transcribe the longest genes which are over 1 megabase long and take many hours to traverse. Dedicated termination mechanisms are required to disrupt these highly stable complexes. Transcription termination occurs not only at the 3' ends of genes once a full length transcript has been made, but also within genes and in promiscuously transcribed intergenic regions. Termination at these latter positions is termed "premature" because it is not triggered in response to a specific signal that marks the 3' end of a gene, like a polyA site. One purpose of premature termination is to remove polymerases from intergenic regions where they are "not wanted" because they may interfere with transcription of overlapping genes or the progress of replication forks. Premature termination has recently been appreciated to occur at surprisingly high rates within genes where it is speculated to serve regulatory or quality control functions. In this review I summarize current understanding of the different mechanisms of premature termination and its potential functions.
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Affiliation(s)
- David L Bentley
- Dept. Biochemistry and Molecular Genetics, RNA Bioscience Initiative, University of Colorado School of Medicine, PO Box 6511, Aurora, CO 80045, USA.
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3
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Walker RL, Hornicek FJ, Duan Z. Transcriptional regulation and therapeutic potential of cyclin-dependent kinase 9 (CDK9) in sarcoma. Biochem Pharmacol 2024; 226:116342. [PMID: 38848777 DOI: 10.1016/j.bcp.2024.116342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2024] [Revised: 05/17/2024] [Accepted: 06/04/2024] [Indexed: 06/09/2024]
Abstract
Sarcomas include various subtypes comprising two significant groups - soft tissue and bone sarcomas. Although the survival rate for some sarcoma subtypes has improved over time, the current methods of treatment remain efficaciously limited, as recurrent, and metastatic diseases remain a major obstacle. There is a need for better options and therapeutic strategies in treating sarcoma. Cyclin dependent kinase 9 (CDK9) is a transcriptional kinase and has emerged as a promising target for treating various cancers. The aberrant expression and activation of CDK9 have been observed in several sarcoma subtypes, including rhabdomyosarcoma, synovial sarcoma, osteosarcoma, Ewing sarcoma, and chordoma. Enhanced CDK9 expression has also been correlated with poorer prognosis in sarcoma patients. As a master regulator of transcription, CDK9 promotes transcription elongation by phosphorylation and releasing RNA polymerase II (RNAPII) from its promoter proximal pause. Release of RNAPII from this pause induces transcription of critical genes in the tumor cell. Overexpression and activation of CDK9 have been observed to lead to the expression of oncogenes, including MYC and MCL-1, that aid sarcoma development and progression. Inhibition of CDK9 in sarcoma has been proven to reduce these oncogenes' expression and decrease proliferation and growth in different sarcoma cells. Currently, there are several CDK9 inhibitors in preclinical and clinical investigations. This review aims to highlight the recent discovery and results on the transcriptional role and therapeutic potential of CDK9 in sarcoma.
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Affiliation(s)
- Robert L Walker
- Department of Orthopedic Surgery, Sarcoma Biology Laboratory, Sylvester Comprehensive Cancer Center, and the University of Miami Miller School of Medicine, Papanicolaou Cancer Research Building, 1550 N.W. 10(th) Avenue, Miami, FL 33136. USA
| | - Francis J Hornicek
- Department of Orthopedic Surgery, Sarcoma Biology Laboratory, Sylvester Comprehensive Cancer Center, and the University of Miami Miller School of Medicine, Papanicolaou Cancer Research Building, 1550 N.W. 10(th) Avenue, Miami, FL 33136. USA
| | - Zhenfeng Duan
- Department of Orthopedic Surgery, Sarcoma Biology Laboratory, Sylvester Comprehensive Cancer Center, and the University of Miami Miller School of Medicine, Papanicolaou Cancer Research Building, 1550 N.W. 10(th) Avenue, Miami, FL 33136. USA.
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4
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Hyder U, Challa A, Thornton M, Nandu T, Kraus WL, D'Orso I. KAP1 negatively regulates RNA polymerase II elongation kinetics to activate signal-induced transcription. Nat Commun 2024; 15:5859. [PMID: 38997286 PMCID: PMC11245487 DOI: 10.1038/s41467-024-49905-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2023] [Accepted: 06/20/2024] [Indexed: 07/14/2024] Open
Abstract
Signal-induced transcriptional programs regulate critical biological processes through the precise spatiotemporal activation of Immediate Early Genes (IEGs); however, the mechanisms of transcription induction remain poorly understood. By combining an acute depletion system with several genomics approaches to interrogate synchronized, temporal transcription, we reveal that KAP1/TRIM28 is a first responder that fulfills the temporal and heightened transcriptional demand of IEGs. Acute KAP1 loss triggers an increase in RNA polymerase II elongation kinetics during early stimulation time points. This elongation defect derails the normal progression through the transcriptional cycle during late stimulation time points, ultimately leading to decreased recruitment of the transcription apparatus for re-initiation thereby dampening IEGs transcriptional output. Collectively, KAP1 plays a counterintuitive role by negatively regulating transcription elongation to support full activation across multiple transcription cycles of genes critical for cell physiology and organismal functions.
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Affiliation(s)
- Usman Hyder
- Department of Microbiology, The University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Ashwini Challa
- Department of Microbiology, The University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Micah Thornton
- Laboratory of Signaling and Gene Regulation, Cecil H. and Ida Green Center for Reproductive Biology Sciences, The University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Tulip Nandu
- Laboratory of Signaling and Gene Regulation, Cecil H. and Ida Green Center for Reproductive Biology Sciences, The University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - W Lee Kraus
- Laboratory of Signaling and Gene Regulation, Cecil H. and Ida Green Center for Reproductive Biology Sciences, The University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Iván D'Orso
- Department of Microbiology, The University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA.
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5
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Cho JH, Chae CW, Lim JR, Jung YH, Han SJ, Yoon JH, Park JY, Han HJ. Sodium butyrate ameliorates high glucose-suppressed neuronal mitophagy by restoring PRKN expression via inhibiting the RELA-HDAC8 complex. Autophagy 2024; 20:1505-1522. [PMID: 38409852 PMCID: PMC11210903 DOI: 10.1080/15548627.2024.2323785] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Revised: 02/14/2024] [Accepted: 02/21/2024] [Indexed: 02/28/2024] Open
Abstract
Damaged mitochondria accumulation in diabetes is one of the main features that contribute to increased incidence of cognitive impairment by inducing apoptosis. Butyrate is a major metabolite produced by microbiota that has neuroprotective effects by regulating mitochondrial function. However, detailed mechanisms underlying how butyrate can regulate neuronal mitophagy remain unclear. Here, we examined the regulatory effects of sodium butyrate (NaB) on high glucose-induced mitophagy dysregulation, neuronal apoptosis, and cognitive impairment and its underlying mechanisms in human-induced pluripotent stem cell-derived neurons, SH-SY5Ys, and streptozotocin (STZ)-induced diabetic mice. In our results, diabetic mice showed gut-microbiota dysbiosis, especially a decreased number of butyrate-producing bacteria and reduced NaB plasma concentration. NaB ameliorated high glucose-induced neuronal mitochondrial dysfunction by recovering PRKN/Parkin-mediated mitophagy. High glucose-induced reactive oxygen species (ROS) and -inhibited PRKAA/AMPKα stimulated the RELA/p65-HDAC8 complex, which downregulated PRKN protein expression by binding to the PRKN promoter region. NaB restored PRKN expression by blocking RELA nuclear translocation and directly inhibiting HDAC8 in the nucleus. In addition, HDAC8 overexpression inhibited the positive effect of NaB on high glucose-induced mitophagy dysfunction and neuronal apoptosis. Oral administration of NaB improved cognitive impairment in diabetic mice by restoring mitophagy in the hippocampus. Taken together, NaB ameliorates neuronal mitophagy through PRKN restoration by inhibiting RELA-HDAC8 complexes, suggesting that NaB is an important substance for protecting neuronal apoptosis in diabetes-associated cognitive impairment.
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Affiliation(s)
- Ji Hyeon Cho
- Department of Veterinary Physiology, College of Veterinary Medicine, Research Institute for Veterinary Science, and BK21 FOUR Future Veterinary Medicine Leading Education & Research Center, Seoul National University, Seoul, South Korea
| | - Chang Woo Chae
- Department of Veterinary Physiology, College of Veterinary Medicine, Research Institute for Veterinary Science, and BK21 FOUR Future Veterinary Medicine Leading Education & Research Center, Seoul National University, Seoul, South Korea
| | - Jae Ryong Lim
- Department of Veterinary Physiology, College of Veterinary Medicine, Research Institute for Veterinary Science, and BK21 FOUR Future Veterinary Medicine Leading Education & Research Center, Seoul National University, Seoul, South Korea
| | - Young Hyun Jung
- Department of Veterinary Physiology, College of Veterinary Medicine, Research Institute for Veterinary Science, and BK21 FOUR Future Veterinary Medicine Leading Education & Research Center, Seoul National University, Seoul, South Korea
| | - Su Jong Han
- Department of Veterinary Physiology, College of Veterinary Medicine, Research Institute for Veterinary Science, and BK21 FOUR Future Veterinary Medicine Leading Education & Research Center, Seoul National University, Seoul, South Korea
| | - Jee Hyeon Yoon
- Department of Veterinary Physiology, College of Veterinary Medicine, Research Institute for Veterinary Science, and BK21 FOUR Future Veterinary Medicine Leading Education & Research Center, Seoul National University, Seoul, South Korea
| | - Ji Yong Park
- Department of Veterinary Physiology, College of Veterinary Medicine, Research Institute for Veterinary Science, and BK21 FOUR Future Veterinary Medicine Leading Education & Research Center, Seoul National University, Seoul, South Korea
| | - Ho Jae Han
- Department of Veterinary Physiology, College of Veterinary Medicine, Research Institute for Veterinary Science, and BK21 FOUR Future Veterinary Medicine Leading Education & Research Center, Seoul National University, Seoul, South Korea
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6
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D'Orso I. The HIV-1 Transcriptional Program: From Initiation to Elongation Control. J Mol Biol 2024:168690. [PMID: 38936695 DOI: 10.1016/j.jmb.2024.168690] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2024] [Revised: 06/20/2024] [Accepted: 06/21/2024] [Indexed: 06/29/2024]
Abstract
A large body of work in the last four decades has revealed the key pillars of HIV-1 transcription control at the initiation and elongation steps. Here, I provide a recount of this collective knowledge starting with the genomic elements (DNA and nascent TAR RNA stem-loop) and transcription factors (cellular and the viral transactivator Tat), and later transitioning to the assembly and regulation of transcription initiation and elongation complexes, and the role of chromatin structure. Compelling evidence support a core HIV-1 transcriptional program regulated by the sequential and concerted action of cellular transcription factors and Tat to promote initiation and sustain elongation, highlighting the efficiency of a small virus to take over its host to produce the high levels of transcription required for viral replication. I summarize new advances including the use of CRISPR-Cas9, genetic tools for acute factor depletion, and imaging to study transcriptional dynamics, bursting and the progression through the multiple phases of the transcriptional cycle. Finally, I describe current challenges to future major advances and discuss areas that deserve more attention to both bolster our basic knowledge of the core HIV-1 transcriptional program and open up new therapeutic opportunities.
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Affiliation(s)
- Iván D'Orso
- Department of Microbiology, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
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7
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Kowalewski A, Borowczak J, Maniewski M, Gostomczyk K, Grzanka D, Szylberg Ł. Targeting apoptosis in clear cell renal cell carcinoma. Biomed Pharmacother 2024; 175:116805. [PMID: 38781868 DOI: 10.1016/j.biopha.2024.116805] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2024] [Revised: 05/16/2024] [Accepted: 05/20/2024] [Indexed: 05/25/2024] Open
Abstract
Clear cell renal cell carcinoma (ccRCC) is the most prevalent subtype of renal cancer, accounting for approximately 80% of all renal cell cancers. Due to its exceptional inter- and intratumor heterogeneity, it is highly resistant to conventional systemic therapies. Targeting the evasion of cell death, one of cancer's hallmarks, is currently emerging as an alternative strategy for ccRCC. In this article, we review the current state of apoptosis-inducing therapies against ccRCC, including antisense oligonucleotides, BH3 mimetics, histone deacetylase inhibitors, cyclin-kinase inhibitors, inhibitors of apoptosis protein antagonists, and monoclonal antibodies. Although preclinical studies have shown encouraging results, these compounds fail to improve patients' outcomes significantly. Current evidence suggests that inducing apoptosis in ccRCC may promote tumor progression through apoptosis-induced proliferation, anastasis, and apoptosis-induced nuclear expulsion. Therefore, re-evaluating this approach is expected to enable successful preclinical-to-clinical translation.
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Affiliation(s)
- Adam Kowalewski
- Department of Tumor Pathology and Pathomorphology, Oncology Centre Prof. Franciszek Łukaszczyk Memorial Hospital, Bydgoszcz 85-796, Poland; Center of Medical Sciences, University of Science and Technology, Bydgoszcz 85-796, Poland.
| | - Jędrzej Borowczak
- Clinical Department of Oncology, Oncology Centre Prof. Franciszek Łukaszczyk Memorial Hospital, Bydgoszcz 85-796, Poland
| | - Mateusz Maniewski
- Department of Tumor Pathology and Pathomorphology, Oncology Centre Prof. Franciszek Łukaszczyk Memorial Hospital, Bydgoszcz 85-796, Poland; Doctoral School of Medical and Health Sciences, Nicolaus Copernicus University in Torun, Bydgoszcz 85-094, Poland
| | - Karol Gostomczyk
- Department of Obstetrics, Gynaecology and Oncology, Chair of Pathomorphology and Clinical Placentology, Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University in Torun, Bydgoszcz 85-094, Poland
| | - Dariusz Grzanka
- Department of Clinical Pathomorphology, Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University in Torun, Bydgoszcz 85-094, Poland
| | - Łukasz Szylberg
- Department of Tumor Pathology and Pathomorphology, Oncology Centre Prof. Franciszek Łukaszczyk Memorial Hospital, Bydgoszcz 85-796, Poland; Department of Obstetrics, Gynaecology and Oncology, Chair of Pathomorphology and Clinical Placentology, Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University in Torun, Bydgoszcz 85-094, Poland
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8
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Vasconcelos Komninakis S, Domingues W, Saeed Sanabani S, Angelo Folgosi V, Neves Barbosa I, Casseb J. CRISPR/CAS as a Powerful Tool for Human Immunodeficiency Virus Cure: A Review. AIDS Res Hum Retroviruses 2024; 40:363-375. [PMID: 38164106 DOI: 10.1089/aid.2022.0148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2024] Open
Abstract
Despite care and the availability of effective antiretroviral treatment, some human immunodeficiency virus (HIV)-infected individuals suffer from neurocognitive disorders associated with HIV (HAND) that significantly affect their quality of life. The different types of HAND can be divided into asymptomatic neurocognitive impairment, mild neurocognitive disorder, and the most severe form known as HIV-associated dementia. Little is known about the mechanisms of HAND, but it is thought to be related to infection of astrocytes, microglial cells, and macrophages in the human brain. The formation of a viral reservoir that lies dormant as a provirus in resting CD4+ T lymphocytes and in refuge tissues such as the brain contributes significantly to HIV eradication. In recent years, a new set of tools have emerged: the gene editing based on the clustered regularly interspaced palindromic repeats (CRISPR)/Cas9 system, which can alter genome segments by insertion, deletion, and replacement and has great therapeutic potential. This technology has been used in research to treat HIV and appears to offer hope for a possible cure for HIV infection and perhaps prevention of HAND. This approach has the potential to directly impact the quality of life of HIV-infected individuals, which is a very important topic to be known and discussed.
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Affiliation(s)
- Shirley Vasconcelos Komninakis
- Laboratory of Medical Investigation (LIM56) of the School of Medicine/Institute de Tropical Medicine, Department of Dermatology, São Paulo University, São Paulo, São Paulo, Brazil
| | - Wilson Domingues
- Laboratory of Medical Investigation (LIM56) of the School of Medicine/Institute de Tropical Medicine, Department of Dermatology, São Paulo University, São Paulo, São Paulo, Brazil
| | - Sabri Saeed Sanabani
- Laboratory of Medical Investigation (LIM56) of the School of Medicine/Institute de Tropical Medicine, Department of Dermatology, São Paulo University, São Paulo, São Paulo, Brazil
| | - Victor Angelo Folgosi
- Laboratory of Medical Investigation (LIM56) of the School of Medicine/Institute de Tropical Medicine, Department of Dermatology, São Paulo University, São Paulo, São Paulo, Brazil
| | - Igor Neves Barbosa
- Institute of Genetic Biology at the Biological Institute of São Paulo University, São Paulo, São Paulo, Brazil
| | - Jorge Casseb
- Laboratory of Medical Investigation (LIM56) of the School of Medicine/Institute de Tropical Medicine, Department of Dermatology, São Paulo University, São Paulo, São Paulo, Brazil
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Singh S, Deshetty UM, Ray S, Oladapo A, Horanieh E, Buch S, Periyasamy P. Non-Coding RNAs in HIV Infection, NeuroHIV, and Related Comorbidities. Cells 2024; 13:898. [PMID: 38891030 PMCID: PMC11171711 DOI: 10.3390/cells13110898] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2024] [Revised: 05/20/2024] [Accepted: 05/22/2024] [Indexed: 06/20/2024] Open
Abstract
NeuroHIV affects approximately 30-60% of people living with HIV-1 (PLWH) and is characterized by varying degrees of cognitive impairments, presenting a multifaceted challenge, the underlying cause of which is chronic, low-level neuroinflammation. Such smoldering neuroinflammation is likely an outcome of lifelong reliance on antiretrovirals coupled with residual virus replication in the brains of PLWH. Despite advancements in antiretroviral therapeutics, our understanding of the molecular mechanism(s) driving inflammatory processes in the brain remains limited. Recent times have seen the emergence of non-coding RNAs (ncRNAs) as critical regulators of gene expression, underlying the neuroinflammatory processes in HIV infection, NeuroHIV, and their associated comorbidities. This review explores the role of various classes of ncRNAs and their regulatory functions implicated in HIV infection, neuropathogenesis, and related conditions. The dysregulated expression of ncRNAs is known to exacerbate the neuroinflammatory responses, thus contributing to neurocognitive impairments in PLWH. This review also discusses the diagnostic and therapeutic potential of ncRNAs in HIV infection and its comorbidities, suggesting their utility as non-invasive biomarkers and targets for modulating neuroinflammatory pathways. Understanding these regulatory roles could pave the way for novel diagnostic strategies and therapeutic interventions in the context of HIV and its comorbidities.
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Affiliation(s)
| | | | | | | | | | - Shilpa Buch
- Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, NE 68198-5880, USA; (S.S.); (U.M.D.); (S.R.); (A.O.); (E.H.)
| | - Palsamy Periyasamy
- Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, NE 68198-5880, USA; (S.S.); (U.M.D.); (S.R.); (A.O.); (E.H.)
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10
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Valdez Capuccino L, Kleitke T, Szokol B, Svajda L, Martin F, Bonechi F, Krekó M, Azami S, Montinaro A, Wang Y, Nikolov V, Kaiser L, Bonasera D, Saggau J, Scholz T, Schmitt A, Beleggia F, Reinhardt HC, George J, Liccardi G, Walczak H, Tóvári J, Brägelmann J, Montero J, Sos ML, Őrfi L, Peltzer N. CDK9 inhibition as an effective therapy for small cell lung cancer. Cell Death Dis 2024; 15:345. [PMID: 38769311 PMCID: PMC11106072 DOI: 10.1038/s41419-024-06724-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Revised: 04/22/2024] [Accepted: 05/07/2024] [Indexed: 05/22/2024]
Abstract
Treatment-naïve small cell lung cancer (SCLC) is typically susceptible to standard-of-care chemotherapy consisting of cisplatin and etoposide recently combined with PD-L1 inhibitors. Yet, in most cases, SCLC patients develop resistance to first-line therapy and alternative therapies are urgently required to overcome this resistance. In this study, we tested the efficacy of dinaciclib, an FDA-orphan drug and inhibitor of the cyclin-dependent kinase (CDK) 9, among other CDKs, in SCLC. Furthermore, we report on a newly developed, highly specific CDK9 inhibitor, VC-1, with tumour-killing activity in SCLC. CDK9 inhibition displayed high killing potential in a panel of mouse and human SCLC cell lines. Mechanistically, CDK9 inhibition led to a reduction in MCL-1 and cFLIP anti-apoptotic proteins and killed cells, almost exclusively, by intrinsic apoptosis. While CDK9 inhibition did not synergise with chemotherapy, it displayed high efficacy in chemotherapy-resistant cells. In vivo, CDK9 inhibition effectively reduced tumour growth and improved survival in both autochthonous and syngeneic SCLC models. Together, this study shows that CDK9 inhibition is a promising therapeutic agent against SCLC and could be applied to chemo-refractory or resistant SCLC.
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Affiliation(s)
- L Valdez Capuccino
- University of Cologne, Faculty of Medicine and University Hospital Cologne, Department of Translational Genomics, Cologne, Germany
- University of Cologne, Faculty of Medicine and University Hospital Cologne, Center for Molecular Medicine Cologne, Cologne, Germany
- CECAD Research Center, University of Cologne, Cologne, Germany
| | - T Kleitke
- University of Cologne, Faculty of Medicine and University Hospital Cologne, Department of Translational Genomics, Cologne, Germany
- University of Cologne, Faculty of Medicine and University Hospital Cologne, Center for Molecular Medicine Cologne, Cologne, Germany
- CECAD Research Center, University of Cologne, Cologne, Germany
| | - B Szokol
- Vichem Chemie Research Ltd., Veszprém, Hungary
| | - L Svajda
- Department of Experimental Pharmacology, and the National Tumor Biology Laboratory, National Institute of Oncology, Budapest, Hungary
| | - F Martin
- Institute for Bioengineering of Catalonia (IBEC), Barcelona Institute of Science and Technology (BIST), 08028, Barcelona, Spain
- Networking Biomedical Research Center in Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), 28029, Madrid, Spain
- Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, University of Barcelona, 08036, Barcelona, Spain
| | - F Bonechi
- University of Cologne, Faculty of Medicine and University Hospital Cologne, Department of Translational Genomics, Cologne, Germany
- University of Cologne, Faculty of Medicine and University Hospital Cologne, Center for Molecular Medicine Cologne, Cologne, Germany
- CECAD Research Center, University of Cologne, Cologne, Germany
| | - M Krekó
- Vichem Chemie Research Ltd., Veszprém, Hungary
- Department of Pharmaceutical Chemistry, Semmelweis University, Budapest, Hungary
| | - S Azami
- University of Cologne, Faculty of Medicine and University Hospital Cologne, Department of Translational Genomics, Cologne, Germany
- University of Cologne, Faculty of Medicine and University Hospital Cologne, Center for Molecular Medicine Cologne, Cologne, Germany
- CECAD Research Center, University of Cologne, Cologne, Germany
| | - A Montinaro
- Centre for Cell Death, Cancer, and Inflammation (CCCI), UCL Cancer Institute, University College London, London, UK
| | - Y Wang
- University of Cologne, Faculty of Medicine and University Hospital Cologne, Department of Translational Genomics, Cologne, Germany
- University of Cologne, Faculty of Medicine and University Hospital Cologne, Center for Molecular Medicine Cologne, Cologne, Germany
- CECAD Research Center, University of Cologne, Cologne, Germany
| | - V Nikolov
- CECAD Research Center, University of Cologne, Cologne, Germany
- Cell death, inflammation and immunity laboratory, Institute of Biochemistry I, Centre for Biochemistry, Faculty of Medicine, University of Cologne, Cologne, Germany
| | - L Kaiser
- University of Cologne, Faculty of Medicine and University Hospital Cologne, Department of Translational Genomics, Cologne, Germany
| | - D Bonasera
- University of Cologne, Faculty of Medicine and University Hospital Cologne, Center for Molecular Medicine Cologne, Cologne, Germany
- Cell death, inflammation and immunity laboratory, Institute of Biochemistry I, Centre for Biochemistry, Faculty of Medicine, University of Cologne, Cologne, Germany
- Genome instability, inflammation and cell death laboratory, Institute of Biochemistry I, Centre for Biochemistry, Faculty of Medicine, University of Cologne, Cologne, Germany
| | - J Saggau
- University of Cologne, Faculty of Medicine and University Hospital Cologne, Center for Molecular Medicine Cologne, Cologne, Germany
- Cell death, inflammation and immunity laboratory, Institute of Biochemistry I, Centre for Biochemistry, Faculty of Medicine, University of Cologne, Cologne, Germany
- Genome instability, inflammation and cell death laboratory, Institute of Biochemistry I, Centre for Biochemistry, Faculty of Medicine, University of Cologne, Cologne, Germany
| | - T Scholz
- University of Cologne, Faculty of Medicine and University Hospital Cologne, Department of Translational Genomics, Cologne, Germany
- University of Cologne, Faculty of Medicine and University Hospital Cologne, Center for Molecular Medicine Cologne, Cologne, Germany
| | - A Schmitt
- University Hospital of Cologne, Medical Faculty, Department I for Internal Medicine, Cologne, Germany
| | - F Beleggia
- University of Cologne, Faculty of Medicine and University Hospital Cologne, Department of Translational Genomics, Cologne, Germany
- University Hospital of Cologne, Medical Faculty, Department I for Internal Medicine, Cologne, Germany
- University of Cologne, Faculty of Medicine and University Hospital Cologne, Mildred Scheel School of Oncology Cologne, Cologne, Germany
| | - H C Reinhardt
- Department of Hematology and Stem Cell Transplantation, University Hospital Essen, University Duisburg-Essen, German Cancer Consortium (DKTK partner site Essen), Essen, Germany
| | - J George
- University of Cologne, Faculty of Medicine and University Hospital Cologne, Department of Translational Genomics, Cologne, Germany
- Department of Otorhinolaryngology, Head and Neck Surgery, Faculty of Medicine and University Hospital Cologne, University Hospital of Cologne, Cologne, Germany
| | - G Liccardi
- University of Cologne, Faculty of Medicine and University Hospital Cologne, Center for Molecular Medicine Cologne, Cologne, Germany
- Genome instability, inflammation and cell death laboratory, Institute of Biochemistry I, Centre for Biochemistry, Faculty of Medicine, University of Cologne, Cologne, Germany
| | - H Walczak
- CECAD Research Center, University of Cologne, Cologne, Germany
- Centre for Cell Death, Cancer, and Inflammation (CCCI), UCL Cancer Institute, University College London, London, UK
- Cell death, inflammation and immunity laboratory, Institute of Biochemistry I, Centre for Biochemistry, Faculty of Medicine, University of Cologne, Cologne, Germany
| | - J Tóvári
- Department of Experimental Pharmacology, and the National Tumor Biology Laboratory, National Institute of Oncology, Budapest, Hungary
| | - J Brägelmann
- University of Cologne, Faculty of Medicine and University Hospital Cologne, Department of Translational Genomics, Cologne, Germany
- University of Cologne, Faculty of Medicine and University Hospital Cologne, Center for Molecular Medicine Cologne, Cologne, Germany
- University of Cologne, Faculty of Medicine and University Hospital Cologne, Mildred Scheel School of Oncology Cologne, Cologne, Germany
| | - J Montero
- Institute for Bioengineering of Catalonia (IBEC), Barcelona Institute of Science and Technology (BIST), 08028, Barcelona, Spain
- Networking Biomedical Research Center in Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), 28029, Madrid, Spain
- Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, University of Barcelona, 08036, Barcelona, Spain
| | - M L Sos
- University of Cologne, Faculty of Medicine and University Hospital Cologne, Department of Translational Genomics, Cologne, Germany
- Division for Translational Oncology, German Cancer Research Center (DKFZ), The German Consortium for Translational Cancer Research (DKTK), München Partner Site, Ludwig-Maximilian University München, Munich, Germany
| | - L Őrfi
- Vichem Chemie Research Ltd., Veszprém, Hungary
- Department of Pharmaceutical Chemistry, Semmelweis University, Budapest, Hungary
| | - N Peltzer
- University of Cologne, Faculty of Medicine and University Hospital Cologne, Department of Translational Genomics, Cologne, Germany.
- University of Cologne, Faculty of Medicine and University Hospital Cologne, Center for Molecular Medicine Cologne, Cologne, Germany.
- CECAD Research Center, University of Cologne, Cologne, Germany.
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11
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Hyder U, Challa A, Thornton M, Nandu T, Kraus WL, D’Orso I. KAP1 negatively regulates RNA polymerase II elongation kinetics to activate signal-induced transcription. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.05.592422. [PMID: 38746145 PMCID: PMC11092767 DOI: 10.1101/2024.05.05.592422] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2024]
Abstract
Signal-induced transcriptional programs regulate critical biological processes through the precise spatiotemporal activation of Immediate Early Genes (IEGs); however, the mechanisms of transcription induction remain poorly understood. By combining an acute depletion system with high resolution genomics approaches to interrogate synchronized, temporal transcription, we reveal that KAP1/TRIM28 is a first responder that fulfills the temporal and heightened transcriptional demand of IEGs. Unexpectedly, acute KAP1 loss triggers an increase in RNA polymerase II elongation kinetics during early stimulation time points. This elongation defect derails the normal progression through the transcriptional cycle during late stimulation time points, ultimately leading to decreased recruitment of the transcription apparatus for re-initiation thereby dampening IEGs transcriptional output. Collectively, KAP1 plays a counterintuitive role by negatively regulating transcription elongation to support full activation across multiple transcription cycles of genes critical for cell physiology and organismal functions.
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Affiliation(s)
- Usman Hyder
- Department of Microbiology, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Ashwini Challa
- Department of Microbiology, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Micah Thornton
- Laboratory of Signaling and Gene Regulation, Cecil H. and Ida Green Center for Reproductive Biology Sciences, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Tulip Nandu
- Laboratory of Signaling and Gene Regulation, Cecil H. and Ida Green Center for Reproductive Biology Sciences, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - W. Lee Kraus
- Laboratory of Signaling and Gene Regulation, Cecil H. and Ida Green Center for Reproductive Biology Sciences, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Iván D’Orso
- Department of Microbiology, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
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12
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Mbonye U, Karn J. The cell biology of HIV-1 latency and rebound. Retrovirology 2024; 21:6. [PMID: 38580979 PMCID: PMC10996279 DOI: 10.1186/s12977-024-00639-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/07/2024] Open
Abstract
Transcriptionally latent forms of replication-competent proviruses, present primarily in a small subset of memory CD4+ T cells, pose the primary barrier to a cure for HIV-1 infection because they are the source of the viral rebound that almost inevitably follows the interruption of antiretroviral therapy. Over the last 30 years, many of the factors essential for initiating HIV-1 transcription have been identified in studies performed using transformed cell lines, such as the Jurkat T-cell model. However, as highlighted in this review, several poorly understood mechanisms still need to be elucidated, including the molecular basis for promoter-proximal pausing of the transcribing complex and the detailed mechanism of the delivery of P-TEFb from 7SK snRNP. Furthermore, the central paradox of HIV-1 transcription remains unsolved: how are the initial rounds of transcription achieved in the absence of Tat? A critical limitation of the transformed cell models is that they do not recapitulate the transitions between active effector cells and quiescent memory T cells. Therefore, investigation of the molecular mechanisms of HIV-1 latency reversal and LRA efficacy in a proper physiological context requires the utilization of primary cell models. Recent mechanistic studies of HIV-1 transcription using latently infected cells recovered from donors and ex vivo cellular models of viral latency have demonstrated that the primary blocks to HIV-1 transcription in memory CD4+ T cells are restrictive epigenetic features at the proviral promoter, the cytoplasmic sequestration of key transcription initiation factors such as NFAT and NF-κB, and the vanishingly low expression of the cellular transcription elongation factor P-TEFb. One of the foremost schemes to eliminate the residual reservoir is to deliberately reactivate latent HIV-1 proviruses to enable clearance of persisting latently infected cells-the "Shock and Kill" strategy. For "Shock and Kill" to become efficient, effective, non-toxic latency-reversing agents (LRAs) must be discovered. Since multiple restrictions limit viral reactivation in primary cells, understanding the T-cell signaling mechanisms that are essential for stimulating P-TEFb biogenesis, initiation factor activation, and reversing the proviral epigenetic restrictions have become a prerequisite for the development of more effective LRAs.
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Affiliation(s)
- Uri Mbonye
- Department of Molecular Biology and Microbiology, Case Western Reserve University School of Medicine, Cleveland, OH, 44106, USA.
| | - Jonathan Karn
- Department of Molecular Biology and Microbiology, Case Western Reserve University School of Medicine, Cleveland, OH, 44106, USA.
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13
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Cisneros WJ, Walter M, Soliman SH, Simons LM, Cornish D, Halle AW, Kim EY, Wolinsky SM, Shilatifard A, Hultquist JF. Release of P-TEFb from the Super Elongation Complex promotes HIV-1 latency reversal. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.01.582881. [PMID: 38464055 PMCID: PMC10925308 DOI: 10.1101/2024.03.01.582881] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/12/2024]
Abstract
The persistence of HIV-1 in long-lived latent reservoirs during suppressive antiretroviral therapy (ART) remains one of the principal barriers to a functional cure. Blocks to transcriptional elongation play a central role in maintaining the latent state, and several latency reversal strategies focus on the release of positive transcription elongation factor b (P-TEFb) from sequestration by negative regulatory complexes, such as the 7SK complex and BRD4. Another major cellular reservoir of P-TEFb is in Super Elongation Complexes (SECs), which play broad regulatory roles in host gene expression. Still, it is unknown if the release of P-TEFb from SECs is a viable latency reversal strategy. Here, we demonstrate that the SEC is not required for HIV-1 replication in primary CD4+ T cells and that a small molecular inhibitor of the P-TEFb/SEC interaction (termed KL-2) increases viral transcription. KL-2 acts synergistically with other latency reversing agents (LRAs) to reactivate viral transcription in several cell line models of latency in a manner that is, at least in part, dependent on the viral Tat protein. Finally, we demonstrate that KL-2 enhances viral reactivation in peripheral blood mononuclear cells (PBMCs) from people living with HIV on suppressive ART, most notably in combination with inhibitor of apoptosis protein antagonists (IAPi). Taken together, these results suggest that the release of P-TEFb from cellular SECs may be a novel route for HIV-1 latency reactivation.
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Affiliation(s)
- William J. Cisneros
- Division of Infectious Diseases, Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
- Center for Pathogen Genomics and Microbial Evolution, Havey Institute for Global Health, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Miriam Walter
- Division of Infectious Diseases, Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Shimaa H.A. Soliman
- Simpson Querrey Institute for Epigenetics, Department of Biochemistry and Molecular Genetics Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Lacy M. Simons
- Division of Infectious Diseases, Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
- Center for Pathogen Genomics and Microbial Evolution, Havey Institute for Global Health, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Daphne Cornish
- Division of Infectious Diseases, Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
- Center for Pathogen Genomics and Microbial Evolution, Havey Institute for Global Health, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Ariel W. Halle
- Division of Infectious Diseases, Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
- Center for Pathogen Genomics and Microbial Evolution, Havey Institute for Global Health, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Eun-Young Kim
- Division of Infectious Diseases, Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Steven M. Wolinsky
- Division of Infectious Diseases, Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Ali Shilatifard
- Simpson Querrey Institute for Epigenetics, Department of Biochemistry and Molecular Genetics Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Judd F. Hultquist
- Division of Infectious Diseases, Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
- Center for Pathogen Genomics and Microbial Evolution, Havey Institute for Global Health, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
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14
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Wang Z, Himanen SV, Haikala HM, Friedel CC, Vihervaara A, Barborič M. Inhibition of CDK12 elevates cancer cell dependence on P-TEFb by stimulation of RNA polymerase II pause release. Nucleic Acids Res 2023; 51:10970-10991. [PMID: 37811895 PMCID: PMC10639066 DOI: 10.1093/nar/gkad792] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Revised: 09/11/2023] [Accepted: 09/22/2023] [Indexed: 10/10/2023] Open
Abstract
P-TEFb and CDK12 facilitate transcriptional elongation by RNA polymerase II. Given the prominence of both kinases in cancer, gaining a better understanding of their interplay could inform the design of novel anti-cancer strategies. While down-regulation of DNA repair genes in CDK12-targeted cancer cells is being explored therapeutically, little is known about mechanisms and significance of transcriptional induction upon inhibition of CDK12. We show that selective targeting of CDK12 in colon cancer-derived cells activates P-TEFb via its release from the inhibitory 7SK snRNP. In turn, P-TEFb stimulates Pol II pause release at thousands of genes, most of which become newly dependent on P-TEFb. Amongst the induced genes are those stimulated by hallmark pathways in cancer, including p53 and NF-κB. Consequently, CDK12-inhibited cancer cells exhibit hypersensitivity to inhibitors of P-TEFb. While blocking P-TEFb triggers their apoptosis in a p53-dependent manner, it impedes cell proliferation irrespective of p53 by preventing induction of genes downstream of the DNA damage-induced NF-κB signaling. In summary, stimulation of Pol II pause release at the signal-responsive genes underlies the functional dependence of CDK12-inhibited cancer cells on P-TEFb. Our study establishes the mechanistic underpinning for combinatorial targeting of CDK12 with either P-TEFb or the induced oncogenic pathways in cancer.
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Affiliation(s)
- Zhijia Wang
- Department of Biochemistry and Developmental Biology, University of Helsinki, Helsinki FIN-00014, Finland
| | - Samu V Himanen
- Department of Gene Technology, KTH Royal Institute of Technology, Science for Life Laboratory, Stockholm, Sweden
| | - Heidi M Haikala
- Translational Immunology Research Program (TRIMM), Research Programs Unit, Faculty of Medicine, University of Helsinki, Helsinki FIN-00014, Finland
- iCAN Digital Precision Cancer Medicine Flagship, University of Helsinki, Helsinki FIN-00014, Finland
| | - Caroline C Friedel
- Institute of Informatics, Ludwig-Maximilians-Universität München, 80333 Munich, Germany
| | - Anniina Vihervaara
- Department of Gene Technology, KTH Royal Institute of Technology, Science for Life Laboratory, Stockholm, Sweden
| | - Matjaž Barborič
- Department of Biochemistry and Developmental Biology, University of Helsinki, Helsinki FIN-00014, Finland
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15
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Atiya A, Shahidi H, Mohammad T, Sharaf SE, Abdulmonem WA, Ashraf GM, Elasbali AM, Alharethi SH, Alhumaydhi FA, Baeesa SS, Rehan M, Shamsi A, Shahwan M. A virtual screening investigation to identify bioactive natural compounds as potential inhibitors of cyclin-dependent kinase 9. J Biomol Struct Dyn 2023; 41:10202-10213. [PMID: 36562191 DOI: 10.1080/07391102.2022.2153921] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Accepted: 11/25/2022] [Indexed: 12/24/2022]
Abstract
Cyclin-dependent kinase 9 (CDK9) is a transcription-associated protein involved in controlling the cell cycle and is often deregulated in stress conditions. CDK9 is being studied as a well-known druggable target for developing effective therapeutics against a wide range of cancer, cardiac dysfunction and inflammatory diseases. Owing to the significance of CDK9 in the etiology of hematological and solid malignancies, its structure, biological activity, regulation and its pharmacological inhibition are being explored for therapeutic management of cancer. We employed a structure-based virtual high-throughput screening of bioactive compounds from the IMPPAT database to discover potential bioactive inhibitors of CDK9. The preliminary results were obtained from the Lipinski criteria, ADMET parameters and sorting compounds without any PAINS patterns. Subsequently, binding affinity and selectivity analyses were used to find effective CDK9 hits. This screening resulted in the identification of two natural compounds, Glabrene and Guggulsterone with high affinity and specificity for the CDK9 binding site. Both compounds exhibit drug-like characteristics, as projected by ADMET analysis, physicochemical data and PASS evaluation. Both compounds preferentially bind to the ATP-binding pocket of CDK9 and interact with functionally important residues. Further, the dynamics and consistency of CDK9 interaction with Glabrene and Guggulsteron were evaluated through all-atom molecular dynamic (MD) simulations which suggested the stability of both complexes. The results might be deployed to introduce novel CDK9 inhibitors that may treat life-threatening diseases, including cancer.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Akhtar Atiya
- Department of Pharmacognosy, College of Pharmacy, King Khalid University (KKU), Abha, Saudi Arabia
| | - Habiba Shahidi
- Department of Computer Science, Jamia Millia Islamia, New Delhi, India
| | - Taj Mohammad
- Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, New Delhi, India
| | - Sharaf E Sharaf
- Pharmaceutical Chemistry Department, College of Pharmacy Umm Al-Qura University Makkah, Saudi Arabia
- Clinical Research Adminstration Executive Adminstration of Research and Innovation King Abdullah Medical City in the Holy Capital Makkah, Makkah, Saudi Arabia
| | - Waleed Al Abdulmonem
- Department of Pathology, College of Medicine, Qassim University, Buraidah, Kingdom of Saudia Arabia
| | - Ghulam Md Ashraf
- Department of Medical Laboratory Sciences, College of Health Sciences, and Sharjah Institute for Medical Research, University of Sharjah, Sharjah, United Arab Emirates
| | | | - Salem Hussain Alharethi
- Department of Biological Science, College of Arts and Science, Najran University, Najran, Saudia Arabia
| | - Fahad A Alhumaydhi
- Department of Medical Laboratories, College of Applied Medical Sciences, Qassim University, Buraidah, Saudi Arabia
| | - Saleh Salem Baeesa
- Division of Neurosurgery, College of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Mohd Rehan
- King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia
- Department of Medical Laboratory Sciences, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Anas Shamsi
- Centre of Medical and Bio-Allied Health Sciences Research, Ajman University, Ajman, United Arab Emirates
| | - Moyad Shahwan
- Centre of Medical and Bio-Allied Health Sciences Research, Ajman University, Ajman, United Arab Emirates
- College of Pharmacy, Ajman University, Ajman, United Arab Emirates
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16
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Ghosh A, Chakraborty P, Biswas D. Fine tuning of the transcription juggernaut: A sweet and sour saga of acetylation and ubiquitination. BIOCHIMICA ET BIOPHYSICA ACTA. GENE REGULATORY MECHANISMS 2023; 1866:194944. [PMID: 37236503 DOI: 10.1016/j.bbagrm.2023.194944] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Revised: 04/26/2023] [Accepted: 05/18/2023] [Indexed: 05/28/2023]
Abstract
Among post-translational modifications of proteins, acetylation, phosphorylation, and ubiquitination are most extensively studied over the last several decades. Owing to their different target residues for modifications, cross-talk between phosphorylation with that of acetylation and ubiquitination is relatively less pronounced. However, since canonical acetylation and ubiquitination happen only on the lysine residues, an overlap of the same lysine residue being targeted for both acetylation and ubiquitination happens quite frequently and thus plays key roles in overall functional regulation predominantly through modulation of protein stability. In this review, we discuss the cross-talk of acetylation and ubiquitination in the regulation of protein stability for the functional regulation of cellular processes with an emphasis on transcriptional regulation. Further, we emphasize our understanding of the functional regulation of Super Elongation Complex (SEC)-mediated transcription, through regulation of stabilization by acetylation, deacetylation and ubiquitination and associated enzymes and its implication in human diseases.
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Affiliation(s)
- Avik Ghosh
- Laboratory of Transcription Biology Molecular Genetics Division, CSIR-Indian Institute of Chemical Biology, 4, Raja S. C. Mullick Road, Kolkata 32, India
| | - Poushali Chakraborty
- Laboratory of Transcription Biology Molecular Genetics Division, CSIR-Indian Institute of Chemical Biology, 4, Raja S. C. Mullick Road, Kolkata 32, India
| | - Debabrata Biswas
- Laboratory of Transcription Biology Molecular Genetics Division, CSIR-Indian Institute of Chemical Biology, 4, Raja S. C. Mullick Road, Kolkata 32, India.
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17
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Pal S, Biswas D. Promoter-proximal regulation of gene transcription: Key factors involved and emerging role of general transcription factors in assisting productive elongation. Gene 2023:147571. [PMID: 37331491 DOI: 10.1016/j.gene.2023.147571] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Revised: 06/02/2023] [Accepted: 06/13/2023] [Indexed: 06/20/2023]
Abstract
The pausing of RNA polymerase II (Pol II) at the promoter-proximal sites is a key rate-limiting step in gene expression. Cells have dedicated a specific set of proteins that sequentially establish pause and then release the Pol II from promoter-proximal sites. A well-controlled pausing and subsequent release of Pol II is crucial for thefine tuning of expression of genes including signal-responsive and developmentally-regulated ones. The release of paused Pol II broadly involves its transition from initiation to elongation. In this review article, we will discuss the phenomenon of Pol II pausing, the underlying mechanism, and also the role of different known factors, with an emphasis on general transcription factors, involved in this overall regulation. We will further discuss some recent findings suggesting a possible role (underexplored) of initiation factors in assisting the transition of transcriptionally-engaged paused Pol II into productive elongation.
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Affiliation(s)
- Sujay Pal
- Laboratory of Transcription Biology, Molecular Genetics Division, CSIR-Indian Institute of Chemical Biology, 4, Raja S. C. Mullick Road, Kolkata - 32, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Debabrata Biswas
- Laboratory of Transcription Biology, Molecular Genetics Division, CSIR-Indian Institute of Chemical Biology, 4, Raja S. C. Mullick Road, Kolkata - 32, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India.
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18
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Chinnapaiyan S, Santiago MJ, Panda K, Rahman MS, Alluin J, Rossi J, Unwalla HJ. A conditional RNA Pol II mono-promoter drives HIV-inducible, CRISPR-mediated cyclin T1 suppression and HIV inhibition. MOLECULAR THERAPY. NUCLEIC ACIDS 2023; 32:553-565. [PMID: 37215150 PMCID: PMC10192333 DOI: 10.1016/j.omtn.2023.04.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Accepted: 04/13/2023] [Indexed: 05/24/2023]
Abstract
Gene editing using clustered regularly interspaced short palindromic repeats (CRISPR) targeted to HIV proviral DNA has shown excision of HIV from infected cells. However, CRISPR-based HIV excision is vulnerable to viral escape. Targeting cellular co-factors provides an attractive yet risky alternative to render viral escape irrelevant. Cyclin T1 is a critical modulator of HIV transcription and mediates recruitment of positive transcription elongation factor-b (P-TEFb) kinase for transcriptional elongation. Hence, a CRISPR-mediated cyclin T1 inactivation will silence HIV transcription, locking it in an inactive form in the cell and thereby serving as an effective antiviral and possibly effecting a functional cure. However, cellular genes play important roles, and their uncontrolled inhibition can promote undesirable effects. Here, we demonstrate a conditional inducible RNA polymerase II (RNA Pol II) mono-promoter-based co-expression of a CRISPR system targeting cyclin T1 from a single transcription unit. Co-expression of guide RNA (gRNA) and CRISPR-associated protein (Cas9) is observed only in HIV-infected cells and leads to sustained HIV suppression in stringent chronically infected cell lines as well as in T cell lines. We further show that incorporation of cis-acting ribozymes immediately upstream of the gRNA further enhances HIV silencing.
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Affiliation(s)
- Srinivasan Chinnapaiyan
- Department of Immunology and Nanomedicine, Institute of Neuroimmune Pharmacology, Herbert Wertheim College of Medicine, Florida International University, Miami, FL 33199, USA
| | - Maria-Jose Santiago
- Department of Immunology and Nanomedicine, Institute of Neuroimmune Pharmacology, Herbert Wertheim College of Medicine, Florida International University, Miami, FL 33199, USA
| | - Kingshuk Panda
- Department of Immunology and Nanomedicine, Institute of Neuroimmune Pharmacology, Herbert Wertheim College of Medicine, Florida International University, Miami, FL 33199, USA
| | - Md. Sohanur Rahman
- Department of Immunology and Nanomedicine, Institute of Neuroimmune Pharmacology, Herbert Wertheim College of Medicine, Florida International University, Miami, FL 33199, USA
| | - Jessica Alluin
- Beckman Research Institute of the City of Hope National Medical Center, Monrovia Biomedical Research Center MBRC, 1218 S. Fifth Av., Monrovia, CA 91008, USA
| | - John Rossi
- Beckman Research Institute of the City of Hope National Medical Center, Monrovia Biomedical Research Center MBRC, 1218 S. Fifth Av., Monrovia, CA 91008, USA
| | - Hoshang J. Unwalla
- Department of Immunology and Nanomedicine, Institute of Neuroimmune Pharmacology, Herbert Wertheim College of Medicine, Florida International University, Miami, FL 33199, USA
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19
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DeBerardine M, Booth GT, Versluis PP, Lis JT. The NELF pausing checkpoint mediates the functional divergence of Cdk9. Nat Commun 2023; 14:2762. [PMID: 37179384 PMCID: PMC10182999 DOI: 10.1038/s41467-023-38359-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Accepted: 04/25/2023] [Indexed: 05/15/2023] Open
Abstract
Promoter-proximal pausing by RNA Pol II is a rate-determining step in gene transcription that is hypothesized to be a prominent point at which regulatory factors act. The pausing factor NELF is known to induce and stabilize pausing, but not all kinds of pausing are NELF-mediated. Here, we find that NELF-depleted Drosophila melanogaster cells functionally recapitulate the NELF-independent pausing we previously observed in fission yeast (which lack NELF). Critically, only NELF-mediated pausing establishes a strict requirement for Cdk9 kinase activity for the release of paused Pol II into productive elongation. Upon inhibition of Cdk9, cells with NELF efficiently shutdown gene transcription, while in NELF-depleted cells, defective, non-productive transcription continues unabated. By introducing a strict checkpoint for Cdk9, the evolution of NELF was likely critical to enable increased regulation of Cdk9 in higher eukaryotes, as Cdk9 availability can be restricted to limit gene transcription without inducing wasteful, non-productive transcription.
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Affiliation(s)
- Michael DeBerardine
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, USA
| | - Gregory T Booth
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, USA
- Kanvas Biosciences, Monmouth Junction, NJ, USA
| | - Philip P Versluis
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, USA
| | - John T Lis
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, USA.
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20
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Mbonye U, Kizito F, Karn J. New insights into transcription elongation control of HIV-1 latency and rebound. Trends Immunol 2023; 44:60-71. [PMID: 36503686 DOI: 10.1016/j.it.2022.11.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Revised: 11/07/2022] [Accepted: 11/09/2022] [Indexed: 12/13/2022]
Abstract
Antiretroviral therapy reduces circulating HIV-1 to undetectable amounts but does not eliminate the virus due to the persistence of a stable reservoir of latently infected cells. The reservoir is maintained both by proliferation of latently infected cells and by reseeding from reactivated cells. A major challenge for the field is to find safe and effective methods to eliminate this source of rebounding HIV-1. Studies on the molecular mechanisms leading to HIV-1 latency and reactivation are being transformed using latency models in primary and patient CD4+ T cells. These studies have revealed the central role played by the biogenesis of the transcription elongation factor P-TEFb (Positive Transcription Elongation Factor b) and its recruitment to proviral HIV-1, for the maintenance of viral latency and the control of viral reactivation.
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Affiliation(s)
- Uri Mbonye
- Department of Molecular Biology and Microbiology, Case Western Reserve University, Cleveland, OH, USA
| | - Fredrick Kizito
- Department of Molecular Biology and Microbiology, Case Western Reserve University, Cleveland, OH, USA
| | - Jonathan Karn
- Department of Molecular Biology and Microbiology, Case Western Reserve University, Cleveland, OH, USA.
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21
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Wang X, Fan Y, Wu Q. The regulation of transcription elongation in embryonic stem cells. Front Cell Dev Biol 2023; 11:1145611. [PMID: 36875763 PMCID: PMC9978399 DOI: 10.3389/fcell.2023.1145611] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Accepted: 02/08/2023] [Indexed: 02/18/2023] Open
Abstract
Transcription elongation is a fundamental molecular process which is accurately regulated to ensure proper gene expression in cellular activities whereas its malfunction is associated with impaired cellular functions. Embryonic stem cells (ESCs) have significant value in regenerative medicine due to their self-renewal ability and their potential to differentiate to almost all types of cells. Therefore, dissection of the exact regulatory mechanism of transcription elongation in ESCs is crucial for both basic research and their clinical applications. In this review, we discuss the current understanding on the regulatory mechanisms of transcription elongation mediated by transcription factors and epigenetic modifications in ESCs.
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Affiliation(s)
- Xuepeng Wang
- The State Key Laboratory of Quality Research in Chinese Medicine, Macau University of Science and Technology, Taipa, Macao SAR, China
| | - Yudan Fan
- The State Key Laboratory of Quality Research in Chinese Medicine, Macau University of Science and Technology, Taipa, Macao SAR, China
| | - Qiang Wu
- The State Key Laboratory of Quality Research in Chinese Medicine, Macau University of Science and Technology, Taipa, Macao SAR, China
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22
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Hu J, Pan D, Li G, Chen K, Hu X. Regulation of programmed cell death by Brd4. Cell Death Dis 2022; 13:1059. [PMID: 36539410 PMCID: PMC9767942 DOI: 10.1038/s41419-022-05505-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Revised: 12/04/2022] [Accepted: 12/07/2022] [Indexed: 12/24/2022]
Abstract
Epigenetic factor Brd4 has emerged as a key regulator of cancer cell proliferation. Targeted inhibition of Brd4 suppresses growth and induces apoptosis of various cancer cells. In addition to apoptosis, Brd4 has also been shown to regulate several other forms of programmed cell death (PCD), including autophagy, necroptosis, pyroptosis, and ferroptosis, with different biological outcomes. PCD plays key roles in development and tissue homeostasis by eliminating unnecessary or detrimental cells. Dysregulation of PCD is associated with various human diseases, including cancer, neurodegenerative and infectious diseases. In this review, we discussed some recent findings on how Brd4 actively regulates different forms of PCD and the therapeutic potentials of targeting Brd4 in PCD-related human diseases. A better understanding of PCD regulation would provide not only new insights into pathophysiological functions of PCD but also provide new avenues for therapy by targeting Brd4-regulated PCD.
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Affiliation(s)
- Jinfeng Hu
- Fujian Key Laboratory of Translational Research in Cancer and Neurodegenerative Diseases, School of Basic Medical Sciences, Fujian Medical University, Fuzhou, 350122, China
| | - Dun Pan
- Department of Gastrointestinal Surgery, The First Affiliated Hospital of Fujian Medical University, Fuzhou, 350005, China
- Fujian Key Laboratory of Translational Research in Cancer and Neurodegenerative Diseases, School of Basic Medical Sciences, Fujian Medical University, Fuzhou, 350122, China
| | - Guo Li
- Fujian Key Laboratory of Translational Research in Cancer and Neurodegenerative Diseases, School of Basic Medical Sciences, Fujian Medical University, Fuzhou, 350122, China
| | - Kunqi Chen
- Key Laboratory of Gastrointestinal Cancer (Ministry of Education), School of Basic Medical Sciences, Fujian Medical University, Fuzhou, 350122, China
| | - Xiangming Hu
- Fujian Key Laboratory of Translational Research in Cancer and Neurodegenerative Diseases, School of Basic Medical Sciences, Fujian Medical University, Fuzhou, 350122, China.
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A transcriptional cycling model recapitulates chromatin-dependent features of noisy inducible transcription. PLoS Comput Biol 2022; 18:e1010152. [PMID: 36084132 PMCID: PMC9491597 DOI: 10.1371/journal.pcbi.1010152] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 09/21/2022] [Accepted: 08/12/2022] [Indexed: 11/23/2022] Open
Abstract
Activation of gene expression in response to environmental cues results in substantial phenotypic heterogeneity between cells that can impact a wide range of outcomes including differentiation, viral activation, and drug resistance. An important source of gene expression noise is transcriptional bursting, or the process by which transcripts are produced during infrequent bursts of promoter activity. Chromatin accessibility impacts transcriptional bursting by regulating the assembly of transcription factor and polymerase complexes on promoters, suggesting that the effect of an activating signal on transcriptional noise will depend on the initial chromatin state at the promoter. To explore this possibility, we simulated transcriptional activation using a transcriptional cycling model with three promoter states that represent chromatin remodeling, polymerase binding and pause release. We initiated this model over a large parameter range representing target genes with different chromatin environments, and found that, upon increasing the polymerase pause release rate to activate transcription, changes in gene expression noise varied significantly across initial promoter states. This model captured phenotypic differences in activation of latent HIV viruses integrated at different chromatin locations and mediated by the transcription factor NF-κB. Activating transcription in the model via increasing one or more of the transcript production rates, as occurs following NF-κB activation, reproduced experimentally measured transcript distributions for four different latent HIV viruses, as well as the bimodal pattern of HIV protein expression that leads to a subset of reactivated virus. Importantly, the parameter ‘activation path’ differentially affected gene expression noise, and ultimately viral activation, in line with experimental observations. This work demonstrates how upstream signaling pathways can be connected to biological processes that underlie transcriptional bursting, resulting in target gene-specific noise profiles following stimulation of a single upstream pathway. Many genes are transcribed in infrequent bursts of mRNA production through a process called transcriptional bursting, which contributes to variability in responses between cells. Heterogeneity in cell responses can have important biological impacts, such as whether a cell supports viral replication or responds to a drug, and thus there is an effort to describe this process with mathematical models to predict biological outcomes. Previous models described bursting as a transition between an “OFF” state or an “ON” state, an elegant and simple mathematical representation of complex molecular mechanisms, but one which failed to capture how upstream activation signals affected bursting. To address this, we added an additional promoter state to better reflect biological mechanisms underlying bursting. By fitting this model to variable activation of quiescent HIV infections in T cells, we showed that our model more accurately described viral expression variability across cells in response to an upstream stimulus. Our work highlights how mathematical models can be further developed to understand complex biological mechanisms and suggests ways to connect transcriptional bursting to upstream activation pathways.
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Mediouni S, Lyu S, Schader SM, Valente ST. Forging a Functional Cure for HIV: Transcription Regulators and Inhibitors. Viruses 2022; 14:1980. [PMID: 36146786 PMCID: PMC9502519 DOI: 10.3390/v14091980] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Revised: 08/28/2022] [Accepted: 09/01/2022] [Indexed: 11/16/2022] Open
Abstract
Current antiretroviral therapy (ART) increases the survival of HIV-infected individuals, yet it is not curative. The major barrier to finding a definitive cure for HIV is our inability to identify and eliminate long-lived cells containing the dormant provirus, termed viral reservoir. When ART is interrupted, the viral reservoir ensures heterogenous and stochastic HIV viral gene expression, which can reseed infection back to pre-ART levels. While strategies to permanently eradicate the virus have not yet provided significant success, recent work has focused on the management of this residual viral reservoir to effectively limit comorbidities associated with the ongoing viral transcription still observed during suppressive ART, as well as limit the need for daily ART. Our group has been at the forefront of exploring the viability of the block-and-lock remission approach, focused on the long-lasting epigenetic block of viral transcription such that without daily ART, there is no risk of viral rebound, transmission, or progression to AIDS. Numerous studies have reported inhibitors of both viral and host factors required for HIV transcriptional activation. Here, we highlight and review some of the latest HIV transcriptional inhibitor discoveries that may be leveraged for the clinical exploration of block-and-lock and revolutionize the way we treat HIV infections.
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Affiliation(s)
- Sonia Mediouni
- Department of Immunology and Microbiology, UF Scripps Biomedical Research, 130 Scripps Way, 3C1, Jupiter, FL 33458, USA
| | - Shuang Lyu
- Department of Immunology and Microbiology, UF Scripps Biomedical Research, 130 Scripps Way, 3C1, Jupiter, FL 33458, USA
| | - Susan M. Schader
- Department of Infectious Disease Research, Drug Development Division, Southern Research, 431 Aviation Way, Frederick, MD 21701, USA
| | - Susana T. Valente
- Department of Immunology and Microbiology, UF Scripps Biomedical Research, 130 Scripps Way, 3C1, Jupiter, FL 33458, USA
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25
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Guo X, Tang T, Duan M, Zhang L, Ge H. The nonequilibrium mechanism of noise-enhanced drug synergy in HIV latency reactivation. iScience 2022; 25:104358. [PMID: 35620426 PMCID: PMC9127169 DOI: 10.1016/j.isci.2022.104358] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 03/04/2022] [Accepted: 04/29/2022] [Indexed: 11/29/2022] Open
Abstract
Noise-modulating chemicals can synergize with transcriptional activators in reactivating latent HIV to eliminate latent HIV reservoirs. To understand the underlying biomolecular mechanism, we investigate a previous two-gene-state model and identify two necessary conditions for the synergy: an assumption of the inhibition effect of transcription activators on noise enhancers; and frequent transitions to the gene non-transcription-permissive state. We then develop a loop-four-gene-state model with Tat transcription/translation and find that drug synergy is mainly determined by the magnitude and direction of energy input into the genetic regulatory kinetics of the HIV promoter. The inhibition effect of transcription activators is actually a phenomenon of energy dissipation in the nonequilibrium gene transition system. Overall, the loop-four-state model demonstrates that energy dissipation plays a crucial role in HIV latency reactivation, which might be useful for improving drug effects and identifying other synergies on lentivirus latency reactivation. The inhibition of Activator on Noise enhancer is necessary for their synergy in reactivating HIV The drug synergy is a nonequilibrium phenomenon in the gene regulatory system The magnitude and direction of energy input determine the drug synergy This nonequilibrium mechanism is general without regarding molecular details
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26
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Ling X, Wu W, Aljahdali IAM, Liao J, Santha S, Fountzilas C, Boland PM, Li F. FL118, acting as a 'molecular glue degrader', binds to dephosphorylates and degrades the oncoprotein DDX5 (p68) to control c-Myc, survivin and mutant Kras against colorectal and pancreatic cancer with high efficacy. Clin Transl Med 2022; 12:e881. [PMID: 35604033 PMCID: PMC9126027 DOI: 10.1002/ctm2.881] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Revised: 04/26/2022] [Accepted: 05/03/2022] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Pancreatic ductal adenocarcinoma (PDAC), a difficult-to-treat cancer, is expected to become the second-largest cause of cancer-related deaths by 2030, while colorectal cancer (CRC) is the third most common cancer and the third leading cause of cancer deaths. Currently, there is no effective treatment for PDAC patients. The development of novel agents to effectively treat these cancers remains an unmet clinical need. FL118, a novel anticancer small molecule, exhibits high efficacy against cancers; however, the direct biochemical target of FL118 is unknown. METHODS FL118 affinity purification, mass spectrometry, Nanosep centrifugal device and isothermal titration calorimetry were used for identifying and confirming FL118 binding to DDX5/p68 and its binding affinity. Immunoprecipitation (IP), western blots, real-time reverse transcription PCR, gene silencing, overexpression (OE) and knockout (KO) were used for analysing gene/protein function and expression. Chromatin IP was used for analysing protein-DNA interactions. The 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromid assay and human PDAC/CRC cell/tumour models were used for determining PDAC/CRC cell/tumour in vitro and in vivo growth. RESULTS We discovered that FL118 strongly binds to dephosphorylates and degrades the DDX5 oncoprotein via the proteasome degradation pathway without decreasing DDX5 mRNA. Silencing and OE of DDX5 indicated that DDX5 is a master regulator for controlling the expression of multiple oncogenic proteins, including survivin, Mcl-1, XIAP, cIAP2, c-Myc and mutant Kras. Genetic manipulation of DDX5 in PDAC cells affects tumour growth. PDAC cells with DDX5 KO are resistant to FL118 treatment. Our human tumour animal model studies further indicated that FL118 exhibits high efficacy to eliminate human PDAC and CRC tumours that have a high expression of DDX5, while FL118 exhibits less effectiveness in PDAC and CRC tumours with low DDX5 expression. CONCLUSION DDX5 is a bona fide FL118 direct target and can act as a biomarker for predicting PDAC and CRC tumour sensitivity to FL118. This would greatly impact FL118 precision medicine for patients with advanced PDAC or advanced CRC in the clinic. FL118 may act as a 'molecular glue degrader' to directly glue DDX5 and ubiquitination regulators together to degrade DDX5.
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Affiliation(s)
- Xiang Ling
- Department of Pharmacology & TherapeuticsRoswell Park Comprehensive Cancer CenterBuffaloNew YorkUSA
- Canget BioTekpharma LLCBuffaloNew YorkUSA
| | - Wenjie Wu
- Department of Pharmacology & TherapeuticsRoswell Park Comprehensive Cancer CenterBuffaloNew YorkUSA
- Canget BioTekpharma LLCBuffaloNew YorkUSA
| | - Ieman A. M. Aljahdali
- Department of Pharmacology & TherapeuticsRoswell Park Comprehensive Cancer CenterBuffaloNew YorkUSA
- Department of Cellular & Molecular BiologyRoswell Park Comprehensive Cancer CenterBuffaloNew YorkUSA
| | | | | | - Christos Fountzilas
- Department of MedicineRoswell Park Comprehensive Cancer CenterBuffaloNew YorkUSA
- Developmental Therapeutics (DT) ProgramRoswell Park Comprehensive Cancer CenterBuffaloNew YorkUSA
| | - Patrick M. Boland
- Department of MedicineRoswell Park Comprehensive Cancer CenterBuffaloNew YorkUSA
- Present address:
Development of Medical Oncology, Rutgers Cancer Institute of New Jersey, The State University of New Jersey, New Brunswick, NJ 08903, USA
| | - Fengzhi Li
- Department of Pharmacology & TherapeuticsRoswell Park Comprehensive Cancer CenterBuffaloNew YorkUSA
- Developmental Therapeutics (DT) ProgramRoswell Park Comprehensive Cancer CenterBuffaloNew YorkUSA
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Lin H, Chen M, Gao Y, Wang Z, Jin F. Tussilagone protects acute lung injury from PM2.5 via alleviating Hif-1α/NF-κB-mediated inflammatory response. ENVIRONMENTAL TOXICOLOGY 2022; 37:1198-1210. [PMID: 35112795 PMCID: PMC9303425 DOI: 10.1002/tox.23476] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Revised: 12/07/2021] [Accepted: 01/16/2022] [Indexed: 05/06/2023]
Abstract
Environmental pollution, especially particulate matter in the air, is a serious threat to human health. Long-term inhalation of particulate matter with a diameter < 2.5 μm (PM2.5) induced irreversible respiratory and lung injury. However, it is not clear whether temporary exposure to massive PM2.5 would result in epithelial damage and lung injury. More importantly, it is urgent to clarify the mechanisms of PM2.5 cytotoxicity and develop a defensive and therapeutic approach. In this study, we demonstrated that temporary exposure with PM2.5 induced lung epithelial cell apoptosis via promoting cytokines expression and inflammatory factors secretion. The cytotoxicity of PM2.5 could be alleviated by tussilagone (TSL), which is a natural compound isolated from the flower buds of Tussilago farfara. The mechanism study indicated that PM2.5 promoted the protein level of Hif-1α by reducing its degradation mediated by PHD2 binding, which furtherly activated NF-κB signaling and inflammatory response. Meanwhile, TSL administration facilitated the interaction of the Hif-1α/PHD2 complex and restored the Hif-1α protein level increased by PM2.5. When PHD2 was inhibited in epithelial cells, the protective function of TSL on PM2.5 cytotoxicity was attenuated and the expression of cytokines was retrieved. Expectedly, the in vivo study also suggested that temporary PM2.5 exposure led to acute lung injury. TSL treatment could effectively relieve the damage and decrease the expression of inflammatory cytokines by repressing Hif-1α level and NF-κB activation. Our findings provide a new therapeutic strategy for air pollution-related respiratory diseases, and TSL would be a potential preventive medicine for PM2.5 cytotoxicity.
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Affiliation(s)
- Hongwei Lin
- Respiration Department of Tangdu Hospital, Air force Military Medical UniversityXi'anChina
| | - Min Chen
- Respiration Department of Tangdu Hospital, Air force Military Medical UniversityXi'anChina
| | - Yanjun Gao
- Respiration Department of Tangdu Hospital, Air force Military Medical UniversityXi'anChina
| | - Zaiqiang Wang
- Respiration Department of Tangdu Hospital, Air force Military Medical UniversityXi'anChina
| | - Faguang Jin
- Respiration Department of Tangdu Hospital, Air force Military Medical UniversityXi'anChina
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Mori L, Valente ST. Cure and Long-Term Remission Strategies. METHODS IN MOLECULAR BIOLOGY (CLIFTON, N.J.) 2022; 2407:391-428. [PMID: 34985678 DOI: 10.1007/978-1-0716-1871-4_26] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The majority of virally suppressed individuals will experience rapid viral rebound upon antiretroviral therapy (ART) interruption, providing a strong rationale for the development of cure strategies. Moreover, despite ART virological control, HIV infection is still associated with chronic immune activation, inflammation, comorbidities, and accelerated aging. These effects are believed to be due, in part, to low-grade persistent transcription and trickling production of viral proteins from the pool of latent proviruses constituting the viral reservoir. In recent years there has been an increasing interest in developing what has been termed a functional cure for HIV. This approach entails the long-term, durable control of viral expression in the absence of therapy, preventing disease progression and transmission, despite the presence of detectable integrated proviruses. One such strategy, the block-and-lock approach for a functional cure, proposes the epigenetic silencing of proviral expression, locking the virus in a profound latent state, from which reactivation is very unlikely. The proof-of-concept for this approach was demonstrated with the use of a specific small molecule targeting HIV transcription. Here we review the principles behind the block-and-lock approach and some of the additional strategies proposed to silence HIV expression.
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Affiliation(s)
- Luisa Mori
- Department of Immunology and Microbiology, The Scripps Research Institute, Jupiter, FL, USA
| | - Susana T Valente
- Department of Immunology and Microbiology, The Scripps Research Institute, Jupiter, FL, USA.
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29
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Zheng L, Feng Z, Tao S, Gao J, Lin Y, Wei X, Zheng B, Huang B, Zheng Z, Zhang X, Liu J, Shan Z, Chen Y, Chen J, Zhao F. Destabilization of macrophage migration inhibitory factor by 4-IPP reduces NF-κB/P-TEFb complex-mediated c-Myb transcription to suppress osteosarcoma tumourigenesis. Clin Transl Med 2022; 12:e652. [PMID: 35060345 PMCID: PMC8777168 DOI: 10.1002/ctm2.652] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 10/27/2021] [Accepted: 11/01/2021] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND As an inflammatory factor and oncogenic driver protein, the pleiotropic cytokine macrophage migration inhibitory factor (MIF) plays a crucial role in the osteosarcoma microenvironment. Although 4-iodo-6-phenylpyrimidine (4-IPP) can inactivate MIF biological functions, its anti-osteosarcoma effect and molecular mechanisms have not been investigated. In this study, we identified the MIF inhibitor 4-IPP as a specific double-effector drug for osteosarcoma with both anti-tumour and anti-osteoclastogenic functions. METHODS The anti-cancer effects of 4-IPP were evaluated by wound healing assay, cell cycle analysis, colony formation assay, CCK-8 assay, apoptosis analysis, and Transwell migration/invasion assays. Through the application of a luciferase reporter, chromatin immunoprecipitation assays, and immunofluorescence and coimmunoprecipitation analyses, the transcriptional regulation of the NF-κB/P-TEFb complex on c-Myb- and STUB1-mediated proteasome-dependent MIF protein degradation was confirmed. The effect of 4-IPP on tumour growth and metastasis was assessed using an HOS-derived tail vein metastasis model and subcutaneous and orthotopic xenograft tumour models. RESULTS In vitro, 4-IPP significantly reduced the proliferation and metastasis of osteosarcoma cells by suppressing the NF-κB pathway. 4-IPP hindered the binding between MIF and CD74 as well as p65. Moreover, 4-IPP inhibited MIF to interrupt the formation of downstream NF-κB/P-TEFb complexes, leading to the down-regulation of c-Myb transcription. Interestingly, the implementation of 4-IPP can mediate small molecule-induced MIF protein proteasomal degradation via the STUB1 E3 ligand. However, 4-IPP still interrupted MIF-mediated communication between osteosarcoma cells and osteoclasts, thus promoting osteoclastogenesis. Remarkably, 4-IPP strongly reduced HOS-derived xenograft osteosarcoma tumourigenesis and metastasis in an in vivo mouse model. CONCLUSIONS Our findings demonstrate that the small molecule 4-IPP targeting the MIF protein exerts an anti-osteosarcoma effect by simultaneously inactivating the biological functions of MIF and promoting its proteasomal degradation. Direct destabilization of the MIF protein with 4-IPP may be a promising therapeutic strategy for treating osteosarcoma.
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Affiliation(s)
- Lin Zheng
- Department of Orthopaedic SurgerySir Run Run Shaw Hospital, Medical College of Zhejiang University & Key Laboratory of Musculoskeletal System Degeneration and Regeneration Translational Research of Zhejiang Province3 East Qingchun RoadHangzhouZhejiang Province310016China
| | - Zhenhua Feng
- Department of Orthopaedic SurgerySir Run Run Shaw Hospital, Medical College of Zhejiang University & Key Laboratory of Musculoskeletal System Degeneration and Regeneration Translational Research of Zhejiang Province3 East Qingchun RoadHangzhouZhejiang Province310016China
| | - Siyue Tao
- Department of Orthopaedic SurgerySir Run Run Shaw Hospital, Medical College of Zhejiang University & Key Laboratory of Musculoskeletal System Degeneration and Regeneration Translational Research of Zhejiang Province3 East Qingchun RoadHangzhouZhejiang Province310016China
| | - Jiawei Gao
- Department of Orthopaedic SurgerySir Run Run Shaw Hospital, Medical College of Zhejiang University & Key Laboratory of Musculoskeletal System Degeneration and Regeneration Translational Research of Zhejiang Province3 East Qingchun RoadHangzhouZhejiang Province310016China
| | - Ye Lin
- Department of Orthopaedic SurgerySir Run Run Shaw Hospital, Medical College of Zhejiang University & Key Laboratory of Musculoskeletal System Degeneration and Regeneration Translational Research of Zhejiang Province3 East Qingchun RoadHangzhouZhejiang Province310016China
| | - Xiaoan Wei
- Department of Orthopaedic SurgerySir Run Run Shaw Hospital, Medical College of Zhejiang University & Key Laboratory of Musculoskeletal System Degeneration and Regeneration Translational Research of Zhejiang Province3 East Qingchun RoadHangzhouZhejiang Province310016China
| | - Bingjie Zheng
- Department of Orthopaedic SurgerySir Run Run Shaw Hospital, Medical College of Zhejiang University & Key Laboratory of Musculoskeletal System Degeneration and Regeneration Translational Research of Zhejiang Province3 East Qingchun RoadHangzhouZhejiang Province310016China
| | - Bao Huang
- Department of Orthopaedic SurgerySir Run Run Shaw Hospital, Medical College of Zhejiang University & Key Laboratory of Musculoskeletal System Degeneration and Regeneration Translational Research of Zhejiang Province3 East Qingchun RoadHangzhouZhejiang Province310016China
| | - Zeyu Zheng
- Department of Orthopaedic SurgerySir Run Run Shaw Hospital, Medical College of Zhejiang University & Key Laboratory of Musculoskeletal System Degeneration and Regeneration Translational Research of Zhejiang Province3 East Qingchun RoadHangzhouZhejiang Province310016China
| | - Xuyang Zhang
- Department of Orthopaedic SurgerySir Run Run Shaw Hospital, Medical College of Zhejiang University & Key Laboratory of Musculoskeletal System Degeneration and Regeneration Translational Research of Zhejiang Province3 East Qingchun RoadHangzhouZhejiang Province310016China
| | - Junhui Liu
- Department of Orthopaedic SurgerySir Run Run Shaw Hospital, Medical College of Zhejiang University & Key Laboratory of Musculoskeletal System Degeneration and Regeneration Translational Research of Zhejiang Province3 East Qingchun RoadHangzhouZhejiang Province310016China
| | - Zhi Shan
- Department of Orthopaedic SurgerySir Run Run Shaw Hospital, Medical College of Zhejiang University & Key Laboratory of Musculoskeletal System Degeneration and Regeneration Translational Research of Zhejiang Province3 East Qingchun RoadHangzhouZhejiang Province310016China
| | - Yilei Chen
- Department of Orthopaedic SurgerySir Run Run Shaw Hospital, Medical College of Zhejiang University & Key Laboratory of Musculoskeletal System Degeneration and Regeneration Translational Research of Zhejiang Province3 East Qingchun RoadHangzhouZhejiang Province310016China
| | - Jian Chen
- Department of Orthopaedic SurgerySir Run Run Shaw Hospital, Medical College of Zhejiang University & Key Laboratory of Musculoskeletal System Degeneration and Regeneration Translational Research of Zhejiang Province3 East Qingchun RoadHangzhouZhejiang Province310016China
| | - Fengdong Zhao
- Department of Orthopaedic SurgerySir Run Run Shaw Hospital, Medical College of Zhejiang University & Key Laboratory of Musculoskeletal System Degeneration and Regeneration Translational Research of Zhejiang Province3 East Qingchun RoadHangzhouZhejiang Province310016China
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Ghafouri-Fard S, Mahmud Hussen B, Abak A, Taheri M, Abdulmajid Ayatollahi S. Emerging role of non-coding RNAs in the course of HIV infection. Int Immunopharmacol 2021; 103:108460. [PMID: 34942460 DOI: 10.1016/j.intimp.2021.108460] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Revised: 11/27/2021] [Accepted: 12/10/2021] [Indexed: 11/05/2022]
Abstract
Recent studies have shown that non-coding region of the human genome can exert important regulatory roles on critical biological functions, including response to viral infections, among them is human immunodeficiency virus (HIV). HIV/AIDS is characterized by a gradual diminution of CD4 + T cells resulting in progressive deterioration of host immune responses and eventually high vulnerability to opportunistic infections and cancer. T cells functions have been shown to be delicately regulated by an active functional network of non-coding RNAs. Several lncRNAs such as MALAT1, NEAT1, GAS5, LOC102549805, NKILA, BACE1-AS, LINC00313, RP11-539L10.2, PVT1, LINC00173, NRON and AK130181 have been found to affect response of immune system to HIV or its pathological consequences. Moreover, numerous miRNAs such as hsa-miR-191-5p, miR-155, miR-103, miR-107, miR-150, miR-144, miR-125b, miR-146a, miR-146b-5p and miR-15a are involved in this process. In the current manuscript, we explain the role of lncRNAs and miRNAs in the regulation of response to HIV infection, apoptosis and activity of T cells, reactivation or latency of this virus and even pathological manifestations such as Tat-mediated induction of astrocytic amyloidosis.
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Affiliation(s)
- Soudeh Ghafouri-Fard
- Department of Medical Genetics, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Bashdar Mahmud Hussen
- Department of Pharmacognosy, College of Pharmacy, Hawler Medical University, Kurdistan Region, Iraq
| | - Atefe Abak
- Men's Health and Reproductive Health Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mohammad Taheri
- Skull Base Research Center, Loghman Hakim Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
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Liu Y, Li L, Timani K, White C, He JJ. Tip110 Expression Facilitates the Release of HEXIM1 and pTEFb from the 7SK Ribonucleoprotein Complex Involving Regulation of the Intracellular Redox Level. Aging Dis 2021; 12:2113-2124. [PMID: 34881089 PMCID: PMC8612609 DOI: 10.14336/ad.2021.0528] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Accepted: 05/28/2021] [Indexed: 11/18/2022] Open
Abstract
HIV-1 Tat-interacting protein of 110 kDa (Tip110; p110nrb/SART3) has been identified to be important for HIV gene transcription and several host gene expression. In this study, we showed that Tip110 was present in the 7SK snRNP through direct binding to MEPCE, a component of the 7SK snRNP complex. In addition, we found a positive association between Tip110 expression, change of HEXIM1 from dimer/oligomer to monomer, and release of HEXIM1 and P-TEFb from the 7SK snRNP complex. A similar association was also noted specifically in nuclear matrix as well as in chromatin where the free HEXIM1 and 7SK snRNP-bound HEXIM1 are located. Moreover, we demonstrated that Tip110 expression was linked to the glutathione metabolic pathway and the intracellular redox level, which in turn regulated HEXIM1 dimerization/oligomerization. Lastly, we performed the FRET microscopic analysis and confirmed the direct relationship between Tip110 expression and HEXIM1 dimerization/oligomerization in vivo. Taken together, these results identified a new mechanism governing HEXIM1 dimerization/oligomerization and the release of HEXIM1 and P-TEFb from the 7SK snRNP complex. These results also yield new insights to the roles of Tip110 in HIV gene transcription and replication.
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Affiliation(s)
- Ying Liu
- 1Department of Microbiology and Immunology.,2Center for Cancer Cell Biology, Immunology and Infection, and
| | - Lu Li
- 1Department of Microbiology and Immunology.,2Center for Cancer Cell Biology, Immunology and Infection, and
| | - Khalid Timani
- 1Department of Microbiology and Immunology.,2Center for Cancer Cell Biology, Immunology and Infection, and
| | - Carl White
- 2Center for Cancer Cell Biology, Immunology and Infection, and.,3Department of Physiology and Biophysics, Rosalind Franklin University of Medicine and Science Chicago Medical School, 3333 Green Bay Road, North Chicago, IL 60064, USA
| | - Johnny J He
- 1Department of Microbiology and Immunology.,2Center for Cancer Cell Biology, Immunology and Infection, and
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32
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RN7SK small nuclear RNA controls bidirectional transcription of highly expressed gene pairs in skin. Nat Commun 2021; 12:5864. [PMID: 34620876 PMCID: PMC8497571 DOI: 10.1038/s41467-021-26083-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Accepted: 09/10/2021] [Indexed: 11/16/2022] Open
Abstract
Pausing of RNA polymerase II (Pol II) close to promoters is a common regulatory step in RNA synthesis, and is coordinated by a ribonucleoprotein complex scaffolded by the noncoding RNA RN7SK. The function of RN7SK-regulated gene transcription in adult tissue homoeostasis is currently unknown. Here, we deplete RN7SK during mouse and human epidermal stem cell differentiation. Unexpectedly, loss of this small nuclear RNA specifically reduces transcription of numerous cell cycle regulators leading to cell cycle exit and differentiation. Mechanistically, we show that RN7SK is required for efficient transcription of highly expressed gene pairs with bidirectional promoters, which in the epidermis co-regulated cell cycle and chromosome organization. The reduction in transcription involves impaired splicing and RNA decay, but occurs in the absence of chromatin remodelling at promoters and putative enhancers. Thus, RN7SK is directly required for efficient Pol II transcription of highly transcribed bidirectional gene pairs, and thereby exerts tissue-specific functions, such as maintaining a cycling cell population in the epidermis. The noncoding RNA RN7SK regulates RNA polymerase II pausing and splicing. Here the authors deplete RN7SK in mouse and human during epidermal stem cell differentiation and reveal a novel role in orchestrating bidirectional transcription of highly expressed gene pairs.
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33
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Tantale K, Garcia-Oliver E, Robert MC, L'Hostis A, Yang Y, Tsanov N, Topno R, Gostan T, Kozulic-Pirher A, Basu-Shrivastava M, Mukherjee K, Slaninova V, Andrau JC, Mueller F, Basyuk E, Radulescu O, Bertrand E. Stochastic pausing at latent HIV-1 promoters generates transcriptional bursting. Nat Commun 2021; 12:4503. [PMID: 34301927 PMCID: PMC8302722 DOI: 10.1038/s41467-021-24462-5] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Accepted: 06/17/2021] [Indexed: 02/06/2023] Open
Abstract
Promoter-proximal pausing of RNA polymerase II is a key process regulating gene expression. In latent HIV-1 cells, it prevents viral transcription and is essential for latency maintenance, while in acutely infected cells the viral factor Tat releases paused polymerase to induce viral expression. Pausing is fundamental for HIV-1, but how it contributes to bursting and stochastic viral reactivation is unclear. Here, we performed single molecule imaging of HIV-1 transcription. We developed a quantitative analysis method that manages multiple time scales from seconds to days and that rapidly fits many models of promoter dynamics. We found that RNA polymerases enter a long-lived pause at latent HIV-1 promoters (>20 minutes), thereby effectively limiting viral transcription. Surprisingly and in contrast to current models, pausing appears stochastic and not obligatory, with only a small fraction of the polymerases undergoing long-lived pausing in absence of Tat. One consequence of stochastic pausing is that HIV-1 transcription occurs in bursts in latent cells, thereby facilitating latency exit and providing a rationale for the stochasticity of viral rebounds.
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Affiliation(s)
- Katjana Tantale
- Institut de Génétique Moléculaire de Montpellier, University of Montpellier, CNRS, Montpellier, France
- Equipe labélisée Ligue Nationale Contre le Cancer, University of Montpellier, CNRS, Montpellier, France
| | - Encar Garcia-Oliver
- Institut de Génétique Moléculaire de Montpellier, University of Montpellier, CNRS, Montpellier, France
| | - Marie-Cécile Robert
- Institut de Génétique Moléculaire de Montpellier, University of Montpellier, CNRS, Montpellier, France
- Equipe labélisée Ligue Nationale Contre le Cancer, University of Montpellier, CNRS, Montpellier, France
- Institut de Génétique Humaine, University of Montpellier, CNRS, Montpellier, France
| | - Adèle L'Hostis
- LPHI, UMR CNRS 5235, University of Montpellier, Montpellier, France
| | - Yueyuxiao Yang
- LPHI, UMR CNRS 5235, University of Montpellier, Montpellier, France
| | - Nikolay Tsanov
- Institut de Génétique Moléculaire de Montpellier, University of Montpellier, CNRS, Montpellier, France
- Equipe labélisée Ligue Nationale Contre le Cancer, University of Montpellier, CNRS, Montpellier, France
| | - Rachel Topno
- Equipe labélisée Ligue Nationale Contre le Cancer, University of Montpellier, CNRS, Montpellier, France
- Institut de Génétique Humaine, University of Montpellier, CNRS, Montpellier, France
- LPHI, UMR CNRS 5235, University of Montpellier, Montpellier, France
| | - Thierry Gostan
- Institut de Génétique Moléculaire de Montpellier, University of Montpellier, CNRS, Montpellier, France
| | - Alja Kozulic-Pirher
- Institut de Génétique Moléculaire de Montpellier, University of Montpellier, CNRS, Montpellier, France
- Equipe labélisée Ligue Nationale Contre le Cancer, University of Montpellier, CNRS, Montpellier, France
| | - Meenakshi Basu-Shrivastava
- Institut de Génétique Moléculaire de Montpellier, University of Montpellier, CNRS, Montpellier, France
- Equipe labélisée Ligue Nationale Contre le Cancer, University of Montpellier, CNRS, Montpellier, France
| | - Kamalika Mukherjee
- Institut de Génétique Moléculaire de Montpellier, University of Montpellier, CNRS, Montpellier, France
- Equipe labélisée Ligue Nationale Contre le Cancer, University of Montpellier, CNRS, Montpellier, France
| | - Vera Slaninova
- Equipe labélisée Ligue Nationale Contre le Cancer, University of Montpellier, CNRS, Montpellier, France
- Institut de Génétique Humaine, University of Montpellier, CNRS, Montpellier, France
| | - Jean-Christophe Andrau
- Institut de Génétique Moléculaire de Montpellier, University of Montpellier, CNRS, Montpellier, France
| | - Florian Mueller
- Unité Imagerie et Modélisation, Institut Pasteur and CNRS UMR 3691, Paris, France
| | - Eugenia Basyuk
- Institut de Génétique Moléculaire de Montpellier, University of Montpellier, CNRS, Montpellier, France.
- Equipe labélisée Ligue Nationale Contre le Cancer, University of Montpellier, CNRS, Montpellier, France.
- Microbiology Fundamental and Pathogenicity CNRS UMR 5234, University of Bordeaux, Bordeaux, France.
| | - Ovidiu Radulescu
- LPHI, UMR CNRS 5235, University of Montpellier, Montpellier, France.
| | - Edouard Bertrand
- Institut de Génétique Moléculaire de Montpellier, University of Montpellier, CNRS, Montpellier, France.
- Equipe labélisée Ligue Nationale Contre le Cancer, University of Montpellier, CNRS, Montpellier, France.
- Institut de Génétique Humaine, University of Montpellier, CNRS, Montpellier, France.
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34
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Abstract
Melanoma is the deadliest form of skin cancer. While clinical developments have significantly improved patient prognosis, effective treatment is often obstructed by limited response rates, intrinsic or acquired resistance to therapy, and adverse events. Melanoma initiation and progression are associated with transcriptional reprogramming of melanocytes to a cell state that resembles the lineage from which the cells are specified during development, that is the neural crest. Convergence to a neural crest cell (NCC)-like state revealed the therapeutic potential of targeting developmental pathways for the treatment of melanoma. Neural crest cells have a unique sensitivity to metabolic dysregulation, especially nucleotide depletion. Mutations in the pyrimidine biosynthesis enzyme dihydroorotate dehydrogenase (DHODH) particularly affect neural crest-derived tissues and cause Miller syndrome, a genetic disorder characterized by craniofacial malformations in patients. The developmental susceptibility of the neural crest to nucleotide deficiency is conserved in melanoma and provides a metabolic vulnerability that can be exploited for therapeutic purposes. We review the current knowledge on nucleotide stress responses in neural crest and melanoma and discuss how the recent scientific advances that have improved our understanding of transcriptional regulation during nucleotide depletion can impact melanoma treatment.
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Affiliation(s)
- Audrey Sporrij
- Harvard Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA, USA.,Stem Cell Program and Division of Hematology/Oncology, Boston Children's Hospital, Boston, MA, USA
| | - Leonard I Zon
- Harvard Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA, USA.,Stem Cell Program and Division of Hematology/Oncology, Boston Children's Hospital, Boston, MA, USA.,Harvard Stem Cell Institute, Harvard Medical School and Howard Hughes Medical Institute, Boston, MA, USA
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35
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CDK9 keeps RNA polymerase II on track. Cell Mol Life Sci 2021; 78:5543-5567. [PMID: 34146121 PMCID: PMC8257543 DOI: 10.1007/s00018-021-03878-8] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Revised: 05/26/2021] [Accepted: 06/08/2021] [Indexed: 12/30/2022]
Abstract
Cyclin-dependent kinase 9 (CDK9), the kinase component of positive transcription elongation factor b (P-TEFb), is essential for transcription of most protein-coding genes by RNA polymerase II (RNAPII). By releasing promoter-proximally paused RNAPII into gene bodies, CDK9 controls the entry of RNAPII into productive elongation and is, therefore, critical for efficient synthesis of full-length messenger (m)RNAs. In recent years, new players involved in P-TEFb-dependent processes have been identified and an important function of CDK9 in coordinating elongation with transcription initiation and termination has been unveiled. As the regulatory functions of CDK9 in gene expression continue to expand, a number of human pathologies, including cancers, have been associated with aberrant CDK9 activity, underscoring the need to properly regulate CDK9. Here, I provide an overview of CDK9 function and regulation, with an emphasis on CDK9 dysregulation in human diseases.
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36
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Cole B, Lambrechts L, Gantner P, Noppe Y, Bonine N, Witkowski W, Chen L, Palmer S, Mullins JI, Chomont N, Pardons M, Vandekerckhove L. In-depth single-cell analysis of translation-competent HIV-1 reservoirs identifies cellular sources of plasma viremia. Nat Commun 2021; 12:3727. [PMID: 34140517 PMCID: PMC8211655 DOI: 10.1038/s41467-021-24080-1] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Accepted: 05/22/2021] [Indexed: 02/07/2023] Open
Abstract
Clonal expansion of HIV-infected cells contributes to the long-term persistence of the HIV reservoir in ART-suppressed individuals. However, the contribution from cell clones that harbor inducible proviruses to plasma viremia is poorly understood. Here, we describe a single-cell approach to simultaneously sequence the TCR, integration sites and proviral genomes from translation-competent reservoir cells, called STIP-Seq. By applying this approach to blood samples from eight participants, we show that the translation-competent reservoir mainly consists of proviruses with short deletions at the 5'-end of the genome, often involving the major splice donor site. TCR and integration site sequencing reveal that cell clones with predicted pathogen-specificity can harbor inducible proviruses integrated into cancer-related genes. Furthermore, we find several matches between proviruses retrieved with STIP-Seq and plasma viruses obtained during ART and upon treatment interruption, suggesting that STIP-Seq can capture clones that are responsible for low-level viremia or viral rebound.
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Affiliation(s)
- Basiel Cole
- HIV Cure Research Center, Department of Internal Medicine and Pediatrics, Ghent University Hospital, Ghent University, Ghent, Belgium
| | - Laurens Lambrechts
- HIV Cure Research Center, Department of Internal Medicine and Pediatrics, Ghent University Hospital, Ghent University, Ghent, Belgium
- BioBix, Department of Data Analysis and Mathematical Modelling, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
| | - Pierre Gantner
- Department of Microbiology, Infectiology and Immunology, Université de Montréal, Montreal, QC, Canada
| | - Ytse Noppe
- HIV Cure Research Center, Department of Internal Medicine and Pediatrics, Ghent University Hospital, Ghent University, Ghent, Belgium
| | - Noah Bonine
- HIV Cure Research Center, Department of Internal Medicine and Pediatrics, Ghent University Hospital, Ghent University, Ghent, Belgium
- BioBix, Department of Data Analysis and Mathematical Modelling, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
| | - Wojciech Witkowski
- HIV Cure Research Center, Department of Internal Medicine and Pediatrics, Ghent University Hospital, Ghent University, Ghent, Belgium
| | - Lennie Chen
- Department of Microbiology, University of Washington, Seattle, WA, USA
| | - Sarah Palmer
- Centre for Virus Research, The Westmead Institute for Medical Research, The University of Sydney, Sydney, NSW, Australia
| | - James I Mullins
- Department of Microbiology, University of Washington, Seattle, WA, USA
- Department of Medicine, University of Washington, Seattle, WA, USA
- Department of Global Health, University of Washington, Seattle, WA, USA
| | - Nicolas Chomont
- Department of Microbiology, Infectiology and Immunology, Université de Montréal, Montreal, QC, Canada
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal, Montreal, QC, Canada
| | - Marion Pardons
- HIV Cure Research Center, Department of Internal Medicine and Pediatrics, Ghent University Hospital, Ghent University, Ghent, Belgium
| | - Linos Vandekerckhove
- HIV Cure Research Center, Department of Internal Medicine and Pediatrics, Ghent University Hospital, Ghent University, Ghent, Belgium.
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37
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Salahong T, Schwartz C, Sungthong R. Are BET Inhibitors yet Promising Latency-Reversing Agents for HIV-1 Reactivation in AIDS Therapy? Viruses 2021; 13:v13061026. [PMID: 34072421 PMCID: PMC8228869 DOI: 10.3390/v13061026] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 05/24/2021] [Accepted: 05/26/2021] [Indexed: 12/26/2022] Open
Abstract
AIDS first emerged decades ago; however, its cure, i.e., eliminating all virus sources, is still unachievable. A critical burden of AIDS therapy is the evasive nature of HIV-1 in face of host immune responses, the so-called "latency." Recently, a promising approach, the "Shock and Kill" strategy, was proposed to eliminate latently HIV-1-infected cell reservoirs. The "Shock and Kill" concept involves two crucial steps: HIV-1 reactivation from its latency stage using a latency-reversing agent (LRA) followed by host immune responses to destroy HIV-1-infected cells in combination with reinforced antiretroviral therapy to kill the progeny virus. Hence, a key challenge is to search for optimal LRAs. Looking at epigenetics of HIV-1 infection, researchers proved that some bromodomains and extra-terminal motif protein inhibitors (BETis) are able to reactivate HIV-1 from latency. However, to date, only a few BETis have shown HIV-1-reactivating functions, and none of them have yet been approved for clinical trial. In this review, we aim to demonstrate the epigenetic roles of BETis in HIV-1 infection and HIV-1-related immune responses. Possible future applications of BETis and their HIV-1-reactivating properties are summarized and discussed.
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Affiliation(s)
- Thanarat Salahong
- Department of Immunology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand;
| | - Christian Schwartz
- Research Unit 7292, DHPI, IUT Louis Pasteur, University of Strasbourg, 67300 Schiltigheim, France
- Correspondence: (C.S.); (R.S.)
| | - Rungroch Sungthong
- Institute of Biodiversity, Animal Health and Comparative Medicine, College of Medical Veterinary and Life Sciences, University of Glasgow, Glasgow G61 1QH, UK
- Laboratory of Hydrology and Geochemistry of Strasbourg, University of Strasbourg, UMR 7517 CNRS/EOST, 67084 Strasbourg CEDEX, France
- Correspondence: (C.S.); (R.S.)
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38
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Devenish LP, Mhlanga MM, Negishi Y. Immune Regulation in Time and Space: The Role of Local- and Long-Range Genomic Interactions in Regulating Immune Responses. Front Immunol 2021; 12:662565. [PMID: 34046034 PMCID: PMC8144502 DOI: 10.3389/fimmu.2021.662565] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Accepted: 04/26/2021] [Indexed: 12/27/2022] Open
Abstract
Mammals face and overcome an onslaught of endogenous and exogenous challenges in order to survive. Typical immune cells and barrier cells, such as epithelia, must respond rapidly and effectively to encountered pathogens and aberrant cells to prevent invasion and eliminate pathogenic species before they become overgrown and cause harm. On the other hand, inappropriate initiation and failed termination of immune cell effector function in the absence of pathogens or aberrant tissue gives rise to a number of chronic, auto-immune, and neoplastic diseases. Therefore, the fine control of immune effector functions to provide for a rapid, robust response to challenge is essential. Importantly, immune cells are heterogeneous due to various factors relating to cytokine exposure and cell-cell interaction. For instance, tissue-resident macrophages and T cells are phenotypically, transcriptionally, and functionally distinct from their circulating counterparts. Indeed, even the same cell types in the same environment show distinct transcription patterns at the single cell level due to cellular noise, despite being robust in concert. Additionally, immune cells must remain quiescent in a naive state to avoid autoimmunity or chronic inflammatory states but must respond robustly upon activation regardless of their microenvironment or cellular noise. In recent years, accruing evidence from next-generation sequencing, chromatin capture techniques, and high-resolution imaging has shown that local- and long-range genome architecture plays an important role in coordinating rapid and robust transcriptional responses. Here, we discuss the local- and long-range genome architecture of immune cells and the resultant changes upon pathogen or antigen exposure. Furthermore, we argue that genome structures contribute functionally to rapid and robust responses under noisy and distinct cellular environments and propose a model to explain this phenomenon.
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Affiliation(s)
- Liam P Devenish
- Division of Chemical, Systems, and Synthetic Biology, Department of Integrative Biomedical Sciences, Institute of Infectious Disease & Molecular Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
| | - Musa M Mhlanga
- Radboud Institute for Molecular Life Sciences (RIMLS), Radboud University Medical Center, Nijmegen, Netherlands.,Epigenomics & Single Cell Biophysics Group, Department of Cell Biology, Radboud University, Nijmegen, Netherlands.,Department of Human Genetics, Radboud University Medical Center, Nijmegen, Netherlands
| | - Yutaka Negishi
- Radboud Institute for Molecular Life Sciences (RIMLS), Radboud University Medical Center, Nijmegen, Netherlands.,Epigenomics & Single Cell Biophysics Group, Department of Cell Biology, Radboud University, Nijmegen, Netherlands.,Department of Human Genetics, Radboud University Medical Center, Nijmegen, Netherlands
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39
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Mehta G, Sharma A, Arora SK. Short Communication: Acquisition of Additional Nuclear Factor Kappa B Binding Sites in Long Terminal Repeat of Genetically Evolving HIV-1 Subtype C Viral Species in Host with Comorbidities. AIDS Res Hum Retroviruses 2021; 37:380-384. [PMID: 33307941 DOI: 10.1089/aid.2020.0195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
HIV-1 causes millions of deaths around the world. Higher disease progression and mortality are seen in HIV positive individuals with comorbidities. Two of the most pertinent conditions are coinfection with Mycobacterium tuberculosis and Intravenous Drug abuse. The mechanisms involved, however, still remain unresolved. To elucidate the mechanisms involved, we evaluated the genetic alterations in terms of additional nuclear factor kappa B (NF-κB) sites in the long terminal repeat (LTR) of HIV-1 subtype-C isolates from infected human individuals from North India, supposedly acquired by the emerging viral quasi-species in the infected host in presence of these two comorbid conditions. Interestingly the results indicate higher number of NF-κB sites in the viral isolates from HIV-tuberculosis coinfected (n = 26, 16 isolates with 3 sites and 10 isolates with 2 sites) and intravenous drug users (n = 20, 13 isolates with 3 sites and 7 isolates with 2 sites) compared to the mono-infected hosts (n = 30, 10 isolates with 3 sites, 18 isolates with 2 sites, 2 isolates with 1 site). The biological relevance of these alterations in the NF-κB sites within the HIV-1 LTR with respect to viral replicative capacity and HIV disease progression needs to be studied further.
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Affiliation(s)
- Gurleen Mehta
- Department of Immunopathology and Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Aman Sharma
- Department of Internal Medicine, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Sunil K. Arora
- Department of Immunopathology and Postgraduate Institute of Medical Education and Research, Chandigarh, India
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40
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Moranguinho I, Valente ST. Block-And-Lock: New Horizons for a Cure for HIV-1. Viruses 2020; 12:v12121443. [PMID: 33334019 PMCID: PMC7765451 DOI: 10.3390/v12121443] [Citation(s) in RCA: 51] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Revised: 12/01/2020] [Accepted: 12/08/2020] [Indexed: 12/12/2022] Open
Abstract
HIV-1/AIDS remains a global public health problem. The world health organization (WHO) reported at the end of 2019 that 38 million people were living with HIV-1 worldwide, of which only 67% were accessing antiretroviral therapy (ART). Despite great success in the clinical management of HIV-1 infection, ART does not eliminate the virus from the host genome. Instead, HIV-1 remains latent as a viral reservoir in any tissue containing resting memory CD4+ T cells. The elimination of these residual proviruses that can reseed full-blown infection upon treatment interruption remains the major barrier towards curing HIV-1. Novel approaches have recently been developed to excise or disrupt the virus from the host cells (e.g., gene editing with the CRISPR-Cas system) to permanently shut off transcription of the virus (block-and-lock and RNA interference strategies), or to reactivate the virus from cell reservoirs so that it can be eliminated by the immune system or cytopathic effects (shock-and-kill strategy). Here, we will review each of these approaches, with the major focus placed on the block-and-lock strategy.
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41
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Sharma V, Montano MM. Non-epigenetic induction of HEXIM1 by DNMT1 inhibitors and functional relevance. Sci Rep 2020; 10:21015. [PMID: 33273553 PMCID: PMC7713402 DOI: 10.1038/s41598-020-78058-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Accepted: 11/17/2020] [Indexed: 11/09/2022] Open
Abstract
We have been studying the role of Hexamethylene bisacetamide (HMBA) Induced Protein 1 (HEXIM1) as a tumor suppressor whose expression is decreased in breast and prostate cancer. The anti-cancer actions of HEXIM1 in melanomas and AML have been reported by other groups. Previous studies have shown that 5-Aza-2'deoxycytidine (5-AzadC), a DNMT1 inhibitor, induces re-expression of tumor suppressor genes by removing/erasing methylation marks from their promoters. Our studies highlighted another mechanism wherein 5-AzadC induced DNA damage, which then resulted in enhanced occupancy of NF-ĸB, P-TEFb, and serine 2 phosphorylated RNA Polymerase II on the HEXIM1 gene. As a consequence, 5-AzadC induced HEXIM1 expression in prostate cancer cell lines and triple negative breast cancers. 5-AzadC-induced DNA damage enhanced P-TEFb occupancy via a mechanism that involved activation of ATR and ATM and induction of NF-ĸB recruitment to the HEXIM1 promoter. Downregulation of NF-ĸB attenuated 5-AzadC-induced HEXIM1 expression in prostate and breast cancer cells. The functional relevance of 5-AzadC-induced HEXIM1 expression is revealed by studies showing the HEXIM1 is required for the induction of apoptosis. Collectively, our findings support a non-epigenetic mechanism for 5-AzadC-induced re-expression of HEXIM1 protein, and may contribute to the clinical efficacy of 5-AzadC.
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Affiliation(s)
- Vikas Sharma
- Department of Pharmacology, School of Medicine, Case Western Reserve University, 10900 Euclid Ave., Cleveland, OH, 44106, USA
| | - Monica M Montano
- Department of Pharmacology, School of Medicine, Case Western Reserve University, 10900 Euclid Ave., Cleveland, OH, 44106, USA.
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42
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Liu Y, Huang ZZ, Min L, Li ZF, Chen K. The BRD4 inhibitor JQ1 protects against chronic obstructive pulmonary disease in mice by suppressing NF-κB activation. Histol Histopathol 2020; 36:101-112. [PMID: 33215396 DOI: 10.14670/hh-18-283] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
OBJECTIVE To examine the effect of the BRD4 inhibitor JQ1 on mice with chronic obstructive pulmonary disease (COPD) via NF-κB. METHODS COPD models constructed by exposure to cigarette smoke and intratracheal instillation of lipopolysaccharides (LPS) in mice were treated with JQ1 (15, 25 or 50 mg/kg). HE staining was performed to observe histopathological changes in the lung tissues. Enzyme-linked immunosorbent assays (ELISAs) were used to measure the levels of IL-10, IFN-γ, IL-17, IL-1β, IL-6, TNF-α, MMP-2, MMP-9, MDA, SOD, T-AOC and HO-1, and gelatin zymography assays were used to examine MMP-2 and MMP-9 activity. A TransAMTM NF-κB p65 detection kit was used to test NF-κB p65/DNA binding activity. Western blotting was conducted to analyze NF-κB p65 in the nucleus and its acetylation. RESULTS JQ1 dose-dependently improved the histopathological changes in the lung tissues and decreased the mean linear intercept (MLI), destructive index and inflammatory score of the mice with COPD. The mice with COPD showed increased levels of MMP-2, MMP-9, IFN-γ, IL-17, IL-1β, IL-6 and TNF-α with decreased IL-10 level; these changes were reversed by JQ1 in a dose-dependent manner. In addition, JQ1 reduced the MDA level and increased the SOD, HO-1 and T-AOC levels in mice with COPD, with suppression of NF-κB p65 expression in the nucleus, NF-κB/p65 (Lys310) acetylation and NF-κB p65/DNA binding activity in the lung tissues. CONCLUSION The BRD4 inhibitor JQ1 can downregulate MMP-2 and MMP-9 expression, reduce inflammatory responses, and alleviate oxidative stress in mice with COPD, and this mechanism might be related to the inhibition of NF-κB.
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Affiliation(s)
- Yan Liu
- Department of Respiratory and Critical Care Medicine, Taihe Hospital, Hubei University of Medicine, Shiyan, Hubei, China
| | - Zhi-Zhen Huang
- Department of Stomatology, Taihe Hospital, Hubei University of Medicine, Shiyan, Hubei, China
| | - Li Min
- Department of Critical Care Medicine, Taihe Hospital, Hubei University of Medicine, Shiyan, Hubei, China
| | - Zhi-Feng Li
- Department of Orthopedics, Taihe Hospital, Hubei University of Medicine, Shiyan, Hubei, China
| | - Kui Chen
- Department of Emergency Medicine, Affiliated Dongfeng Hospital, Hubei University of Medicine, Shiyan, Hubei, China.
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Ni W, Zhang F, Zheng L, Wang L, Liang Y, Ding Y, Yik JHN, Haudenschild DR, Fan S, Hu Z. Cyclin-Dependent Kinase 9 (CDK9) Inhibitor Atuveciclib Suppresses Intervertebral Disk Degeneration via the Inhibition of the NF-κB Signaling Pathway. Front Cell Dev Biol 2020; 8:579658. [PMID: 33015073 PMCID: PMC7511812 DOI: 10.3389/fcell.2020.579658] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Accepted: 08/20/2020] [Indexed: 12/30/2022] Open
Abstract
Intervertebral disk degeneration (IVDD) is a spinal disk condition caused by an inflammatory response induced by various proinflammatory cytokines, such as interleukin (IL)-1β and tumor necrosis factor (TNF)-α. cyclin-dependent kinase 9 (CDK9) is a transcriptional regulator and potential therapeutic target for many diseases, especially in regulating the activation of primary inflammatory response genes. Our study investigated a highly selective CDK9 inhibitor, atuveciclib, which protects nucleus pulposus (NP) cells from proinflammatory stimuli-induced catabolism. The effects of CDK9 inhibition were determined in human and rat NP cells treated with IL-1β in the presence or absence of atuveciclib or small interfering RNA target CDK9. Inhibition of CDK9 led to the attenuation of inflammatory response. In addition, rat intervertebral disk (IVD) explants were used to determine the role of CDK9 inhibition in extracellular matrix degradation. The rat IVDD model also proved that CDK9 inhibition attenuated IVDD, as validated using magnetic resonance imaging and immunohistochemistry. Taken together, CDK9 is a potential therapeutic target to prevent IVDD.
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Affiliation(s)
- Weiyu Ni
- Department of Orthopaedic Surgery, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China.,Key Laboratory of Musculoskeletal System Degeneration and Regeneration Translational Research, Zhejiang University School of Medicine, Hangzhou, China
| | - Feizhou Zhang
- The Children's Hospital of Zhejiang University School of Medicine, Hangzhou, China
| | - Lin Zheng
- Department of Orthopaedic Surgery, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China.,Key Laboratory of Musculoskeletal System Degeneration and Regeneration Translational Research, Zhejiang University School of Medicine, Hangzhou, China
| | - Lili Wang
- School of Statistics and Mathematics, Zhejiang Gongshang University, Hangzhou, China
| | - Yi Liang
- Department of Orthopaedic Surgery, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China.,Key Laboratory of Musculoskeletal System Degeneration and Regeneration Translational Research, Zhejiang University School of Medicine, Hangzhou, China
| | - Yuhong Ding
- Department of Orthopaedic Surgery, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China.,Key Laboratory of Musculoskeletal System Degeneration and Regeneration Translational Research, Zhejiang University School of Medicine, Hangzhou, China
| | - Jasper H N Yik
- Department of Orthopaedic Surgery, UC Davis Medical Center, Sacramento, CA, United States
| | - Dominik R Haudenschild
- Department of Orthopaedic Surgery, UC Davis Medical Center, Sacramento, CA, United States
| | - Shunwu Fan
- Department of Orthopaedic Surgery, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China.,Key Laboratory of Musculoskeletal System Degeneration and Regeneration Translational Research, Zhejiang University School of Medicine, Hangzhou, China
| | - Ziang Hu
- Department of Orthopaedic Surgery, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China.,Key Laboratory of Musculoskeletal System Degeneration and Regeneration Translational Research, Zhejiang University School of Medicine, Hangzhou, China
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NF-κB-Interacting Long Noncoding RNA Regulates HIV-1 Replication and Latency by Repressing NF-κB Signaling. J Virol 2020; 94:JVI.01057-20. [PMID: 32581100 DOI: 10.1128/jvi.01057-20] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Accepted: 06/16/2020] [Indexed: 12/22/2022] Open
Abstract
NF-κB-interacting long noncoding RNA (NKILA) was recently identified as a negative regulator of NF-κB signaling and plays an important role in the development of various cancers. It is well known that NF-κB-mediated activation of human immunodeficiency virus type 1 (HIV-1) long terminal repeat (LTR)-driven gene expression is required for HIV-1 transcription and reactivation of latency. However, whether NKILA plays essential roles in HIV-1 replication and latency is unclear. Here, by ectopic expression and silencing experiments, we demonstrate that NKILA potently inhibits HIV-1 replication in an NF-κB-dependent manner by suppressing HIV-1 LTR promoter activity. Moreover, NKILA showed broad-spectrum inhibition on the replication of HIV-1 clones with different coreceptor tropisms as well as on LTR activity of various HIV-1 clinical subtypes. Chromatin immunoprecipitation (ChIP) assays revealed that NKILA expression abolishes the recruitment of p65 to the duplicated κB binding sites in the HIV-1 LTR. NKILA mutants disrupting NF-κB inhibition also lost the ability to inhibit HIV-1 replication. Notably, HIV-1 infection or reactivation significantly downregulated NKILA expression in T cells in order to facilitate viral replication. Downregulated NKILA was mainly due to reduced acetylation of histone K27 on the promoter of NKILA by HIV-1 infection, which blocks NKILA expression. Knockdown of NKILA promoted the reactivation of latent HIV-1 upon phorbol myristate acetate (PMA) stimulation, while ectopic NKILA suppressed the reactivation in a well-established clinical model of withdrawal of azidothymidine (AZT) in vitro These findings improve our understanding of the functional suppression of HIV-1 replication and latency by NKILA through NF-κB signaling.IMPORTANCE The NF-κB pathway plays key roles in HIV-1 replication and reactivation of HIV-1 latency. A regulator inhibiting NF-κB activation may be a promising therapeutic strategy against HIV-1. Recently, NF-κB-interacting long noncoding RNA (NKILA) was identified to suppress the development of different human cancers by inhibiting IκB kinase (IKK)-induced IκB phosphorylation and NF-κB pathway activation, whereas the relationship between NKILA and HIV-1 replication is still unknown. Here, our results show that NKILA inhibits HIV-1 replication and reactivation by suppressing HIV-1 long terminal repeat (LTR)-driven transcription initiation. Moreover, NKILA inhibited the replication of HIV-1 clones with different coreceptor tropisms. This project may reveal a target for the development of novel anti-HIV drugs.
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Cassandri M, Fioravanti R, Pomella S, Valente S, Rotili D, Del Baldo G, De Angelis B, Rota R, Mai A. CDK9 as a Valuable Target in Cancer: From Natural Compounds Inhibitors to Current Treatment in Pediatric Soft Tissue Sarcomas. Front Pharmacol 2020; 11:1230. [PMID: 32903585 PMCID: PMC7438590 DOI: 10.3389/fphar.2020.01230] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Accepted: 07/28/2020] [Indexed: 12/20/2022] Open
Abstract
Cyclin-Dependent Kinases (CDKs) are well-known reliable targets for cancer treatment being often deregulated. Among them, since the transcription-associated CDK9 represents the sentry of cell transcriptional homeostasis, it can be a valuable target for managing cancers in which the transcriptional machinery is dysregulated by tumor-driver oncogenes. Here we give an overview of some natural compounds identified as CDK inhibitors with reported activity also against CDK9, that were taken as a model for the development of highly active synthetic anti-CDK9 agents. After, we summarize the data on CDK9 inhibition in a group of rare pediatric solid tumors such as rhabdomyosarcoma, Ewing’s sarcoma, synovial sarcoma and malignant rhabdoid tumors (soft tissue sarcomas), highlighting the more recent results in this field. Finally, we discuss the perspective and challenge of CDK9 modulation in cancer.
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Affiliation(s)
- Matteo Cassandri
- Department of Oncohematology, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Rossella Fioravanti
- Department of Drug Chemistry and Technologies, Sapienza University of Rome, Rome, Italy
| | - Silvia Pomella
- Department of Oncohematology, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Sergio Valente
- Department of Drug Chemistry and Technologies, Sapienza University of Rome, Rome, Italy
| | - Dante Rotili
- Department of Drug Chemistry and Technologies, Sapienza University of Rome, Rome, Italy
| | - Giada Del Baldo
- Department of Oncohematology, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Biagio De Angelis
- Department of Oncohematology, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Rossella Rota
- Department of Oncohematology, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Antonello Mai
- Department of Drug Chemistry and Technologies, Sapienza University of Rome, Rome, Italy
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Abstract
Although antiretroviral therapies (ARTs) potently inhibit HIV replication, they do not eradicate the virus. HIV persists in cellular and anatomical reservoirs that show minimal decay during ART. A large number of studies conducted during the past 20 years have shown that HIV persists in a small pool of cells harboring integrated and replication-competent viral genomes. The majority of these cells do not produce viral particles and constitute what is referred to as the latent reservoir of HIV infection. Therefore, although HIV is not considered as a typical latent virus, it can establish a state of nonproductive infection under rare circumstances, particularly in memory CD4+ T cells, which represent the main barrier to HIV eradication. While it was originally thought that the pool of latently infected cells was largely composed of cells harboring transcriptionally silent genomes, recent evidence indicates that several blocks contribute to the nonproductive state of these cells. Here, we describe the virological and immunological factors that play a role in the establishment and persistence of the pool of latently infected cells and review the current approaches aimed at eliminating the latent HIV reservoir.
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Affiliation(s)
| | - Pierre Gantner
- Department of Microbiology, Infectiology and Immunology and
| | - Rémi Fromentin
- Centre de Recherche du Centre Hospitalier, Université de Montréal, Montreal, Quebec, Canada
| | - Nicolas Chomont
- Department of Microbiology, Infectiology and Immunology and
- Centre de Recherche du Centre Hospitalier, Université de Montréal, Montreal, Quebec, Canada
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Bacon CW, Challa A, Hyder U, Shukla A, Borkar AN, Bayo J, Liu J, Wu SY, Chiang CM, Kutateladze TG, D'Orso I. KAP1 Is a Chromatin Reader that Couples Steps of RNA Polymerase II Transcription to Sustain Oncogenic Programs. Mol Cell 2020; 78:1133-1151.e14. [PMID: 32402252 PMCID: PMC7305985 DOI: 10.1016/j.molcel.2020.04.024] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Revised: 02/25/2020] [Accepted: 04/17/2020] [Indexed: 01/08/2023]
Abstract
Precise control of the RNA polymerase II (RNA Pol II) cycle, including pausing and pause release, maintains transcriptional homeostasis and organismal functions. Despite previous work to understand individual transcription steps, we reveal a mechanism that integrates RNA Pol II cycle transitions. Surprisingly, KAP1/TRIM28 uses a previously uncharacterized chromatin reader cassette to bind hypo-acetylated histone 4 tails at promoters, guaranteeing continuous progression of RNA Pol II entry to and exit from the pause state. Upon chromatin docking, KAP1 first associates with RNA Pol II and then recruits a pathway-specific transcription factor (SMAD2) in response to cognate ligands, enabling gene-selective CDK9-dependent pause release. This coupling mechanism is exploited by tumor cells to aberrantly sustain transcriptional programs commonly dysregulated in cancer patients. The discovery of a factor integrating transcription steps expands the functional repertoire by which chromatin readers operate and provides mechanistic understanding of transcription regulation, offering alternative therapeutic opportunities to target transcriptional dysregulation.
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Affiliation(s)
- Curtis W Bacon
- Department of Microbiology, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Biological Chemistry Graduate Program, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Ashwini Challa
- Department of Microbiology, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Usman Hyder
- Department of Microbiology, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Ashutosh Shukla
- Department of Microbiology, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Aditi N Borkar
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK
| | - Juan Bayo
- Instituto de Investigaciones en Medicina Traslacional, Facultad de Ciencias Biomédicas, CONICET, Universidad Austral, Derqui-Pilar, Buenos Aires 1629, Argentina
| | - Jiuyang Liu
- Department of Pharmacology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Shwu-Yuan Wu
- Harold C. Simmons Comprehensive Cancer Center, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Department of Biochemistry, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Cheng-Ming Chiang
- Harold C. Simmons Comprehensive Cancer Center, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Department of Biochemistry, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Department of Pharmacology, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Tatiana G Kutateladze
- Department of Pharmacology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Iván D'Orso
- Department of Microbiology, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
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Mori L, Valente ST. Key Players in HIV-1 Transcriptional Regulation: Targets for a Functional Cure. Viruses 2020; 12:E529. [PMID: 32403278 PMCID: PMC7291152 DOI: 10.3390/v12050529] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Revised: 05/07/2020] [Accepted: 05/08/2020] [Indexed: 12/13/2022] Open
Abstract
HIV-1 establishes a life-long infection when proviral DNA integrates into the host genome. The provirus can then either actively transcribe RNA or enter a latent state, without viral production. The switch between these two states is governed in great part by the viral protein, Tat, which promotes RNA transcript elongation. Latency is also influenced by the availability of host transcription factors, integration site, and the surrounding chromatin environment. The latent reservoir is established in the first few days of infection and serves as the source of viral rebound upon treatment interruption. Despite effective suppression of HIV-1 replication by antiretroviral therapy (ART), to below the detection limit, ART is ineffective at reducing the latent reservoir size. Elimination of this reservoir has become a major goal of the HIV-1 cure field. However, aside from the ideal total HIV-1 eradication from the host genome, an HIV-1 remission or functional cure is probably more realistic. The "block-and-lock" approach aims at the transcriptional silencing of the viral reservoir, to render suppressed HIV-1 promoters extremely difficult to reactivate from latency. There are unfortunately no clinically available HIV-1 specific transcriptional inhibitors. Understanding the mechanisms that regulate latency is expected to provide novel targets to be explored in cure approaches.
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Affiliation(s)
| | - Susana T. Valente
- Department of Immunology and Microbiology, The Scripps Research Institute, 130 Scripps Way, Jupiter, FL 33458, USA;
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Negative elongation factor complex enables macrophage inflammatory responses by controlling anti-inflammatory gene expression. Nat Commun 2020; 11:2286. [PMID: 32385332 PMCID: PMC7210294 DOI: 10.1038/s41467-020-16209-5] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2019] [Accepted: 04/21/2020] [Indexed: 01/06/2023] Open
Abstract
Studies on macrophage gene expression have historically focused on events leading to RNA polymerase II recruitment and transcription initiation, whereas the contribution of post-initiation steps to macrophage activation remains poorly understood. Here, we report that widespread promoter-proximal RNA polymerase II pausing in resting macrophages is marked by co-localization of the negative elongation factor (NELF) complex and facilitated by PU.1. Upon inflammatory stimulation, over 60% of activated transcriptome is regulated by polymerase pause-release and a transient genome-wide NELF dissociation from chromatin, unexpectedly, independent of CDK9, a presumed NELF kinase. Genetic disruption of NELF in macrophages enhanced transcription of AP-1-encoding Fos and Jun and, consequently, AP-1 targets including Il10. Augmented expression of IL-10, a critical anti-inflammatory cytokine, in turn, attenuated production of pro-inflammatory mediators and, ultimately, macrophage-mediated inflammation in vivo. Together, these findings establish a previously unappreciated role of NELF in constraining transcription of inflammation inhibitors thereby enabling inflammatory macrophage activation. Macrophage activation is integral to innate immunity and inflammation, and involves transcriptome remodeling leading to the rapid upregulation of pro- and anti-inflammatory effector genes. Here the authors show that the negative elongation factor (NELF) complex controls the transcription of anti-inflammatory genes through Pol II pause release.
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50
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Basu S, Nandy A, Biswas D. Keeping RNA polymerase II on the run: Functions of MLL fusion partners in transcriptional regulation. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2020; 1863:194563. [PMID: 32348849 DOI: 10.1016/j.bbagrm.2020.194563] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 01/13/2020] [Accepted: 04/13/2020] [Indexed: 12/21/2022]
Abstract
Since the identification of key MLL fusion partners as transcription elongation factors regulating expression of HOX cluster genes during hematopoiesis, extensive work from the last decade has resulted in significant progress in our overall mechanistic understanding of role of MLL fusion partner proteins in transcriptional regulation of diverse set of genes beyond just the HOX cluster. In this review, we are going to detail overall understanding of role of MLL fusion partner proteins in transcriptional regulation and thus provide mechanistic insights into possible MLL fusion protein-mediated transcriptional misregulation leading to aberrant hematopoiesis and leukemogenesis.
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Affiliation(s)
- Subham Basu
- Laboratory of Transcription Biology, Molecular Genetics Division, CSIR-Indian Institute of Chemical Biology, 4, Raja S. C. Mullick Road, Kolkata 32, India
| | - Arijit Nandy
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
| | - Debabrata Biswas
- Laboratory of Transcription Biology, Molecular Genetics Division, CSIR-Indian Institute of Chemical Biology, 4, Raja S. C. Mullick Road, Kolkata 32, India.
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