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Rosendo-Chalma P, Antonio-Véjar V, Ortiz Tejedor JG, Ortiz Segarra J, Vega Crespo B, Bigoni-Ordóñez GD. The Hallmarks of Cervical Cancer: Molecular Mechanisms Induced by Human Papillomavirus. BIOLOGY 2024; 13:77. [PMID: 38392296 PMCID: PMC10886769 DOI: 10.3390/biology13020077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/24/2023] [Revised: 01/17/2024] [Accepted: 01/23/2024] [Indexed: 02/24/2024]
Abstract
Human papillomaviruses (HPVs) and, specifically, high-risk HPVs (HR-HPVs) are identified as necessary factors in the development of cancer of the lower genital tract, with CaCU standing out as the most prevalent tumor. This review summarizes ten mechanisms activated by HR-HPVs during cervical carcinogenesis, which are broadly associated with at least seven of the fourteen distinctive physiological capacities of cancer in the newly established model by Hanahan in 2022. These mechanisms involve infection by human papillomavirus, cellular tropism, genetic predisposition to uterine cervical cancer (CaCU), viral load, viral physical state, regulation of epigenetic mechanisms, loss of function of the E2 protein, deregulated expression of E6/E7 oncogenes, regulation of host cell protein function, and acquisition of the mesenchymal phenotype.
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Affiliation(s)
- Pedro Rosendo-Chalma
- Laboratorio de Virus y Cáncer, Unidad de Investigación Biomédica en Cáncer of Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México (IIB-UNAM), Mexico City 14080, Mexico
- Unidad Académica de Posgrado, Universidad Católica de Cuenca, Cuenca 010101, Ecuador
| | - Verónica Antonio-Véjar
- Laboratorio de Biomedicina Molecular, Facultad de Ciencias Químico Biológicas, Universidad Autónoma de Guerrero, Chilpancingo 39090, Guerrero, Mexico
| | - Jonnathan Gerardo Ortiz Tejedor
- Unidad Académica de Posgrado, Universidad Católica de Cuenca, Cuenca 010101, Ecuador
- Carrera de Bioquímica y Farmacia, Universidad Católica de Cuenca, Cuenca 010101, Ecuador
| | - Jose Ortiz Segarra
- Carrera de Medicina, Facultad de Ciencias Médicas, Universidad de Cuenca, Cuenca 010107, Ecuador
| | - Bernardo Vega Crespo
- Carrera de Medicina, Facultad de Ciencias Médicas, Universidad de Cuenca, Cuenca 010107, Ecuador
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Skelin J, Tomaić V. Comparative Analysis of Alpha and Beta HPV E6 Oncoproteins: Insights into Functional Distinctions and Divergent Mechanisms of Pathogenesis. Viruses 2023; 15:2253. [PMID: 38005929 PMCID: PMC10674601 DOI: 10.3390/v15112253] [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: 10/27/2023] [Revised: 11/09/2023] [Accepted: 11/10/2023] [Indexed: 11/26/2023] Open
Abstract
Human papillomaviruses (HPVs) represent a diverse group of DNA viruses that infect epithelial cells of mucosal and cutaneous tissues, leading to a wide spectrum of clinical outcomes. Among various HPVs, alpha (α) and beta (β) types have garnered significant attention due to their associations with human health. α-HPVs are primarily linked to infections of the mucosa, with high-risk subtypes, such as HPV16 and HPV18, being the major etiological agents of cervical and oropharyngeal cancers. In contrast, β-HPVs are predominantly associated with cutaneous infections and are commonly found on healthy skin. However, certain β-types, notably HPV5 and HPV8, have been implicated in the development of non-melanoma skin cancers in immunocompromised individuals, highlighting their potential role in pathogenicity. In this review, we comprehensively analyze the similarities and differences between α- and β-HPV E6 oncoproteins, one of the major drivers of viral replication and cellular transformation, and how these impact viral fitness and the capacity to induce malignancy. In particular, we compare the mechanisms these oncoproteins use to modulate common cellular processes-apoptosis, DNA damage repair, cell differentiation, and the immune response-further shedding light on their shared and distinct features, which enable them to replicate at divergent locations of the human body and cause different types of cancer.
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Affiliation(s)
| | - Vjekoslav Tomaić
- Division of Molecular Medicine, Ruđer Bošković Institute, Bijenička 54, 10000 Zagreb, Croatia;
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3
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Chand V, Kapoor A, Kundu S, Nag A. Identification of a peptide that disrupts hADA3-E6 interaction with implications in HPV induced cancer therapy. Life Sci 2022; 288:120157. [PMID: 34801511 DOI: 10.1016/j.lfs.2021.120157] [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: 08/27/2021] [Revised: 11/04/2021] [Accepted: 11/12/2021] [Indexed: 11/28/2022]
Abstract
AIM High risk Human Papillomavirus (HPV) is an infectious pathogen implicated in a variety of cancers with poor clinical outcome. The mechanism of HPV induced cellular transformation and its intervention remains to be elucidated. Human ADA3 (hADA3), a cellular target of HPV16 E6, is an essential and conserved component of the ADA transcriptional coactivator complex. High risk HPV-E6 binds and functionally inactivates hADA3 to initiate oncogenesis. The aim of this study was to identify the interaction interface between hADA3 and HPV16E6 for designing inhibitory peptides that can potentially disrupt the hADA3-E6 interaction. MATERIAL METHODS The present investigation employed structure-based in silico tools supported by biochemical validation, in vivo interaction studies and analysis of posttranslational modifications. KEY FINDINGS First 3D-model of hADA3 was proposed and domains involved in the oncogenic interaction between hADA3 and HPV16E6 were delineated. Rationally designed peptide disrupted hADA3-E6 interaction and impeded malignant properties of cervical cancer cells. SIGNIFICANCE Intervention of hADA3-E6 interaction thus promises to be a potential strategy to combat HPV induced oncogenic conditions like cervical cancer. The investigation provides mechanistic insights into HPV pathogenesis and shows promise in developing novel therapeutics to treat HPV induced cancers.
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Affiliation(s)
- Vaibhav Chand
- Department of Biochemistry, University of Delhi South Campus, New Delhi 110021, India
| | - Abhijeet Kapoor
- Department of Biochemistry, University of Delhi South Campus, New Delhi 110021, India
| | - Suman Kundu
- Department of Biochemistry, University of Delhi South Campus, New Delhi 110021, India.
| | - Alo Nag
- Department of Biochemistry, University of Delhi South Campus, New Delhi 110021, India.
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Human Papillomaviruses-Associated Cancers: An Update of Current Knowledge. Viruses 2021; 13:v13112234. [PMID: 34835040 PMCID: PMC8623401 DOI: 10.3390/v13112234] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Revised: 10/26/2021] [Accepted: 10/29/2021] [Indexed: 12/21/2022] Open
Abstract
Human papillomaviruses (HPVs), which are small, double-stranded, circular DNA viruses infecting human epithelial cells, are associated with various benign and malignant lesions of mucosa and skin. Intensive research on the oncogenic potential of HPVs started in the 1970s and spread across Europe, including Croatia, and worldwide. Nowadays, the causative role of a subset of oncogenic or high-risk (HR) HPV types, led by HPV-16 and HPV-18, of different anogenital and head and neck cancers is well accepted. Two major viral oncoproteins, E6 and E7, are directly involved in the development of HPV-related malignancies by targeting synergistically various cellular pathways involved in the regulation of cell cycle control, apoptosis, and cell polarity control networks as well as host immune response. This review is aimed at describing the key elements in HPV-related carcinogenesis and the advances in cancer prevention with reference to past and on-going research in Croatia.
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Basukala O, Banks L. The Not-So-Good, the Bad and the Ugly: HPV E5, E6 and E7 Oncoproteins in the Orchestration of Carcinogenesis. Viruses 2021; 13:1892. [PMID: 34696321 PMCID: PMC8541208 DOI: 10.3390/v13101892] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 09/13/2021] [Accepted: 09/14/2021] [Indexed: 12/15/2022] Open
Abstract
Infection with HPV starts with the access of the viral particles to basal cells in the epidermis, potentially via microtraumas to the skin. The basal cells are able to keep away these pathogens in normal circumstances through a robust immune response from the host, as HPV infections are, in general, cleared within 2 to 3 weeks. However, the rare instances of persistent infection and/or in cases where the host immune system is compromised are major risk factors for the development of lesions potentially leading to malignancy. Evolutionarily, obligatory pathogens such as HPVs would not be expected to risk exposing the host to lethal cancer, as this would entail challenging their own life cycle, but infection with these viruses is highly correlated with cancer and malignancy-as in cancer of the cervix, which is almost always associated with these viruses. Despite this key associative cause and the availability of very effective vaccines against these viruses, therapeutic interventions against HPV-induced cancers are still a challenge, indicating the need for focused translational research. In this review, we will consider the key roles that the viral proteins play in driving the host cells to carcinogenesis, mainly focusing on events orchestrated by early proteins E5, E6 and E7-the not-so-good, the bad and the ugly-and discuss and summarize the major events that lead to these viruses mechanistically corrupting cellular homeostasis, giving rise to cancer and malignancy.
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Affiliation(s)
| | - Lawrence Banks
- Tumour Virology Laboratory, International Centre for Genetic Engineering and Biotechnology, Padriciano 99, I-34149 Trieste, Italy;
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Malik RM, Fazal S, Kamal MA. Computational Analysis of Domains Vulnerable to HPV-16 E6 Oncoprotein and Corresponding Hot Spot Residues. Protein Pept Lett 2021; 28:414-425. [PMID: 32703126 DOI: 10.2174/0929866527666200722134801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 06/19/2020] [Accepted: 06/28/2020] [Indexed: 02/08/2023]
Abstract
BACKGROUND Human Papilloma Virus (HPV) is the primary cause of cancers in cervix, head and neck regions. Oncoprotein E6 of HPV-16, after infecting human body, alters host protein- protein interaction networks. E6 interacts with several proteins, causing the infection to progress into cervical cancer. The molecular basis for these interactions is the presence of short linear peptide motifs on E6 identical to those on human proteins. METHODS Motifs of LXXLL and E/DLLL/V-G after identification on E6, were analyzed for their dynamic fluctuations by use of elastic network models. Correlation analysis of amino acid residues of E6 was also performed in specific regions of motifs. RESULTS Arginine, Leucine, Glutamine, Threonine and Glutamic acid have been identified as hot spot residues of E6 which can subsequently provide a platform for drug designing and understanding of pathogenesis of cervical cancer. These amino acids play a significant role in stabilizing interactions with host proteins, ultimately causing infections and cancers. CONCLUSION Our study validates the role of linear binding motifs of E6 of HPV in interacting with these proteins as an important event in the propagation of HPV in human cells and its transformation into cervical cancer. The study further predicts the domains of protein kinase and armadillo as part of the regions involved in the interaction of E6AP, Paxillin and TNF R1, with viral E6.
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Affiliation(s)
| | - Sahar Fazal
- Capital University of Science and Technology, Islamabad, Pakistan
| | - Mohammad Amjad Kamal
- West China School of Nursing / Institutes for Systems Genetics, Frontiers Science Center for Disease-related Molecular Network, West China Hospital, Sichuan University, Chengdu 610041, Sichuan, China
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7
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Chitsike L, Duerksen-Hughes PJ. PPI Modulators of E6 as Potential Targeted Therapeutics for Cervical Cancer: Progress and Challenges in Targeting E6. Molecules 2021; 26:molecules26103004. [PMID: 34070144 PMCID: PMC8158384 DOI: 10.3390/molecules26103004] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 05/05/2021] [Accepted: 05/15/2021] [Indexed: 12/13/2022] Open
Abstract
Advanced cervical cancer is primarily managed using cytotoxic therapies, despite evidence of limited efficacy and known toxicity. There is a current lack of alternative therapeutics to treat the disease more effectively. As such, there have been more research endeavors to develop targeted therapies directed at oncogenic host cellular targets over the past 4 decades, but thus far, only marginal gains in survival have been realized. The E6 oncoprotein, a protein of human papillomavirus origin that functionally inactivates various cellular antitumor proteins through protein–protein interactions (PPIs), represents an alternative target and intriguing opportunity to identify novel and potentially effective therapies to treat cervical cancer. Published research has reported a number of peptide and small-molecule modulators targeting the PPIs of E6 in various cell-based models. However, the reported compounds have rarely been well characterized in animal or human subjects. This indicates that while notable progress has been made in targeting E6, more extensive research is needed to accelerate the optimization of leads. In this review, we summarize the current knowledge and understanding of specific E6 PPI inhibition, the progress and challenges being faced, and potential approaches that can be utilized to identify novel and potent PPI inhibitors for cervical cancer treatment.
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Scarth JA, Patterson MR, Morgan EL, Macdonald A. The human papillomavirus oncoproteins: a review of the host pathways targeted on the road to transformation. J Gen Virol 2021; 102:001540. [PMID: 33427604 PMCID: PMC8148304 DOI: 10.1099/jgv.0.001540] [Citation(s) in RCA: 79] [Impact Index Per Article: 26.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Accepted: 11/25/2020] [Indexed: 12/24/2022] Open
Abstract
Persistent infection with high-risk human papillomaviruses (HR-HPVs) is the causal factor in over 99 % of cervical cancer cases, and a significant proportion of oropharyngeal and anogenital cancers. The key drivers of HPV-mediated transformation are the oncoproteins E5, E6 and E7. Together, they act to prolong cell-cycle progression, delay differentiation and inhibit apoptosis in the host keratinocyte cell in order to generate an environment permissive for viral replication. The oncoproteins also have key roles in mediating evasion of the host immune response, enabling infection to persist. Moreover, prolonged infection within the cellular environment established by the HR-HPV oncoproteins can lead to the acquisition of host genetic mutations, eventually culminating in transformation to malignancy. In this review, we outline the many ways in which the HR-HPV oncoproteins manipulate the host cellular environment, focusing on how these activities can contribute to carcinogenesis.
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Affiliation(s)
- James A. Scarth
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, West Yorkshire, LS2 9JT, UK
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, West Yorkshire, LS2 9JT, UK
| | - Molly R. Patterson
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, West Yorkshire, LS2 9JT, UK
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, West Yorkshire, LS2 9JT, UK
| | - Ethan L. Morgan
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, West Yorkshire, LS2 9JT, UK
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, West Yorkshire, LS2 9JT, UK
- Present address: Tumour Biology Section, Head and Neck Surgery Branch, National Institute on Deafness and Other Communication Disorders, National Institute of Health, Bethesda, MD 20892, USA
| | - Andrew Macdonald
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, West Yorkshire, LS2 9JT, UK
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, West Yorkshire, LS2 9JT, UK
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9
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Zema S, Pelullo M, Nardozza F, Felli MP, Screpanti I, Bellavia D. A Dynamic Role of Mastermind-Like 1: A Journey Through the Main (Path)ways Between Development and Cancer. Front Cell Dev Biol 2020; 8:613557. [PMID: 33425921 PMCID: PMC7787167 DOI: 10.3389/fcell.2020.613557] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Accepted: 11/30/2020] [Indexed: 12/12/2022] Open
Abstract
Major signaling pathways, such as Notch, Hedgehog (Hh), Wnt/β-catenin and Hippo, are targeted by a plethora of physiological and pathological stimuli, ultimately resulting in the modulation of genes that act coordinately to establish specific biological processes. Many biological programs are strictly controlled by the assembly of multiprotein complexes into the nucleus, where a regulated recruitment of specific transcription factors and coactivators on gene promoter region leads to different transcriptional outcomes. MAML1 results to be a versatile coactivator, able to set up synergistic interlinking with pivotal signaling cascades and able to coordinate the network of cross-talking pathways. Accordingly, despite its original identification as a component of the Notch signaling pathway, several recent reports suggest a more articulated role for MAML1 protein, showing that it is able to sustain/empower Wnt/β-catenin, Hh and Hippo pathways, in a Notch-independent manner. For this reason, MAML1 may be associated to a molecular “switch”, with the function to control the activation of major signaling pathways, triggering in this way critical biological processes during embryonic and post-natal life. In this review, we summarize the current knowledge about the pleiotropic role played by MAML proteins, in particular MAML1, and we recapitulate how it takes part actively in physiological and pathological signaling networks. On this point, we also discuss the contribution of MAML proteins to malignant transformation. Accordingly, genetic alterations or impaired expression of MAML proteins may lead to a deregulated crosstalk among the pathways, culminating in a series of pathological disorders, including cancer development. Given their central role, a better knowledge of the molecular mechanisms that regulate the interplay of MAML proteins with several signaling pathways involved in tumorigenesis may open up novel opportunities for an attractive molecular targeted anticancer therapy.
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Affiliation(s)
- Sabrina Zema
- Department of Medico-Surgical Sciences and Biotechnology, Sapienza University, Latina, Italy
| | - Maria Pelullo
- Center for Life Nano Science@Sapienza, Istituto Italiano di Tecnologia, Rome, Italy
| | | | - Maria Pia Felli
- Department of Experimental Medicine, Sapienza University, Rome, Italy
| | | | - Diana Bellavia
- Department of Molecular Medicine, Sapienza University, Rome, Italy
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10
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The Association and Significance of p53 in Gynecologic Cancers: The Potential of Targeted Therapy. Int J Mol Sci 2019; 20:ijms20215482. [PMID: 31689961 PMCID: PMC6862296 DOI: 10.3390/ijms20215482] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Revised: 10/28/2019] [Accepted: 11/02/2019] [Indexed: 12/16/2022] Open
Abstract
Dysfunction of p53 is observed in the many malignant tumors. In cervical cancer, p53 is inactivated by degradation through the complex with human papilloma virus (HPV) oncoprotein E6 and E6-associated protein (E6AP), an E3 ubiquitin protein ligase. In endometrial cancer, overexpression of p53 in immunohistochemistry is a significant prognostic factor. A discrepancy between p53 overexpression and TP53 mutations is observed in endometrioid endometrial cancer, indicating that the accumulation of p53 protein can be explained by not only gene mutations but also dysregulation of the factors such as ERβ and MDM2. Furthermore, the double-positive expression of immunoreactive estrogen receptor (ER) β and p53 proteins is closely associated with the incidence of metastasis and/or recurrence. High-grade serous ovarian carcinoma (HGSC) arises from secretary cells in the fallopian tube. The secretary cell outgrowth (SCOUT) with TP53 mutations progresses to HGSC via the p53 signature, serous intraepithelial lesion (STIL), and serous intraepithelial carcinoma (STIC), indicating that TP53 mutation is associated with carcinogenesis of HGSC. Clinical application targeting p53 has been approved for some malignant tumors. Gene therapy by the adenovirus-mediated p53 gene transfer system is performed for head and neck cancer. A clinical phase III trial using MDM2/X inhibitors, idasanutlin (RG7388) combined with cytarabine, is being performed involving relapse/refractory acute myeloid leukemia patients. The use of adenoviruses as live vectors which encode wild-type p53 has given promising results in cervical cancer patients.
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Taghizadeh E, Jahangiri S, Rostami D, Taheri F, Renani PG, Taghizadeh H, Gheibi Hayat SM. Roles of E6 and E7 Human Papillomavirus Proteins in Molecular Pathogenesis of Cervical Cancer. Curr Protein Pept Sci 2019; 20:926-934. [DOI: 10.2174/1389203720666190618101441] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 05/11/2019] [Accepted: 05/26/2019] [Indexed: 01/07/2023]
Abstract
Human papillomavirus (HPV) cancers are expected to be major global health concerns in the upcoming decades. The growth of HPV-positive cancer cells depends on the consistent expression of oncoprotein which has been poorly taken into account in the cellular communication. Among them, E6/E7 oncoproteins are attractive therapeutic targets as their inhibition rapidly leads to the onset of aging in HPV-positive cancer cells. This cellular response is associated with the regeneration of p53, pRb anti-proliferative proteins as well as the mTOR signaling pathway; hence, the identification of involved and application of E6/E7 inhibitors can lead to new therapeutic strategies. In the present review, we focused on the pathogenicity of E6/E7 Proteins of human papillomavirus and their roles associated with the cervical cancer.
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Affiliation(s)
- Eskandar Taghizadeh
- Cellular and Molecular Research Center, Yasuj University of Medical Sciences, Yasuj, Iran
| | - Sepideh Jahangiri
- Genetics department, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran
| | - Daryoush Rostami
- Department of School Allied, Zabol University of Medical Sciences, Zabol, Iran
| | - Forough Taheri
- Shahrekord Branch, Islamic Azad University, Shahrekord, Iran
| | | | - Hassan Taghizadeh
- Cellular and Molecular Research Center, Yasuj University of Medical Sciences, Yasuj, Iran
| | - Seyed Mohammad Gheibi Hayat
- Department of Medical Genetics, School of Medicine, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
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King E, Ottensmeier C, Pollock KGJ. Novel Approaches for Vaccination Against HPV-Induced Cancers. Curr Top Microbiol Immunol 2019; 405:33-53. [PMID: 25735921 DOI: 10.1007/82_2015_430] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
To date, more than 5 % of all cancers are as a result of human papillomavirus (HPV) infection, and this incidence is increasing. Early recognition of disease is associated with good survival, but late presentation results in devastating consequences. Prevention is better than cure, and there are now successful prophylactic vaccination programmes in place. We discuss these and the prospect of therapeutic vaccinations in the near future to address a growing need for improved therapeutic options.
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Affiliation(s)
- Emma King
- University of Southampton, Southampton, UK.
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13
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Zhang S, Xu L, Tang Z, Wang H, Gu J, Sun B, Zhang W, Niu D, Feng J. Overexpression of Alteration/Deficiency in Activation 3 correlates with poor prognosis in non-small cell lung cancer. Pathol Res Pract 2019; 215:152408. [PMID: 30954347 DOI: 10.1016/j.prp.2019.03.036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Revised: 03/17/2019] [Accepted: 03/31/2019] [Indexed: 12/24/2022]
Abstract
Alteration/Deficiency in Activation 3 (ADA3), the human homologue of yeast ADA3, is involved in a variety of cell biological processes and plays an important role in tumorigenesis. Here, western blotting and reverse-transcription quantitative PCR (RT-qPCR) were conducted to explore the expression pattern of ADA3 in non-small cell lung cancer (NSCLC) patients. It was found that ADA3 protein expression in cancerous tissues was significantly higher than that in adjacent normal lung tissues, but there were no differences in mRNA levels. Tissue microarray immunohistochemical assay (TMA-IHC) was performed and we investigated the prognostic significance of ADA3 expression in 84 cases of NSCLC. Survival analyses showed that high expression of ADA3 was an independent prognostic factor for unfavorable overall survival (OS) in patients with NSCLC. In summary, the ADA3 expression level elevates in NSCLC and correlates with poor OS in NSCLC patients.
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Affiliation(s)
- Shuwen Zhang
- Department of Respiratory and Critical Care Medicine, Affiliated Hospital of Nantong University, Nantong, 226001, Jiangsu, China
| | - Liqin Xu
- Department of Respiratory and Critical Care Medicine, Affiliated Hospital of Nantong University, Nantong, 226001, Jiangsu, China
| | - Zhiyuan Tang
- Department of Respiratory and Critical Care Medicine, Affiliated Hospital of Nantong University, Nantong, 226001, Jiangsu, China
| | - Haiying Wang
- Department of Respiratory and Critical Care Medicine, Affiliated Hospital of Nantong University, Nantong, 226001, Jiangsu, China
| | - Jun Gu
- Department of Respiratory and Critical Care Medicine, Affiliated Hospital of Nantong University, Nantong, 226001, Jiangsu, China
| | - Baier Sun
- Department of Respiratory and Critical Care Medicine, Affiliated Hospital of Nantong University, Nantong, 226001, Jiangsu, China
| | - Weishuai Zhang
- Department of Respiratory and Critical Care Medicine, Affiliated Hospital of Nantong University, Nantong, 226001, Jiangsu, China
| | - Donghua Niu
- Department of Respiratory and Critical Care Medicine, Affiliated Hospital of Nantong University, Nantong, 226001, Jiangsu, China
| | - Jian Feng
- Department of Respiratory and Critical Care Medicine, Affiliated Hospital of Nantong University, Nantong, 226001, Jiangsu, China.
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14
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Estêvão D, Costa NR, Gil da Costa RM, Medeiros R. Hallmarks of HPV carcinogenesis: The role of E6, E7 and E5 oncoproteins in cellular malignancy. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2019; 1862:153-162. [PMID: 30707946 DOI: 10.1016/j.bbagrm.2019.01.001] [Citation(s) in RCA: 72] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Revised: 01/15/2019] [Accepted: 01/16/2019] [Indexed: 01/06/2023]
Abstract
Human papillomavirus (HPV) is the most common sexually transmitted infectious agent worldwide, being also responsible for 5% of all human cancers. The integration and hypermethylation mechanisms of the HPV viral genome promote the unbalanced expression of the E6, E7 and E5 oncoproteins, which are crucial factors for the carcinogenic cascade in HPV-induced cancers. This review highlights the action of E6, E7 and E5 over key regulatory targets, promoting all known hallmarks of cancer. Both well-characterized and novel targets of these HPV oncoproteins are described, detailing their mechanisms of action. Finally, this review approaches the possibility of targeting E6, E7 and E5 for therapeutic applications in the context of cancer.
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Affiliation(s)
- Diogo Estêvão
- Molecular Oncology and Viral Pathology Group, IPO-Porto Research Center (CI-IPOP), Portuguese Institute of Oncology of Porto (IPO-Porto), Rua Dr. António Bernardino de Almeida, 4200-072 Porto, Portugal; FMUP, Faculty of Medicine, University of Porto, Alameda Professor Hernâni Monteiro, 4200-319 Porto, Portugal
| | - Natália Rios Costa
- Molecular Oncology and Viral Pathology Group, IPO-Porto Research Center (CI-IPOP), Portuguese Institute of Oncology of Porto (IPO-Porto), Rua Dr. António Bernardino de Almeida, 4200-072 Porto, Portugal
| | - Rui M Gil da Costa
- Molecular Oncology and Viral Pathology Group, IPO-Porto Research Center (CI-IPOP), Portuguese Institute of Oncology of Porto (IPO-Porto), Rua Dr. António Bernardino de Almeida, 4200-072 Porto, Portugal; Center for the Research and Technology of Agro-Environmental and Biological Sciences (CITAB), University of Trás-os-Montes and Alto Douro, UTAD, Quinta de Prados, 5001-911 Vila Real, Portugal
| | - Rui Medeiros
- Molecular Oncology and Viral Pathology Group, IPO-Porto Research Center (CI-IPOP), Portuguese Institute of Oncology of Porto (IPO-Porto), Rua Dr. António Bernardino de Almeida, 4200-072 Porto, Portugal; FMUP, Faculty of Medicine, University of Porto, Alameda Professor Hernâni Monteiro, 4200-319 Porto, Portugal; LPCC, Research Department Portuguese League Against Cancer (Liga Portuguesa Contra o Cancro-Núcleo Regional do Norte), Estrada Interior da Circunvalação, no. 6657, 4200-177 Porto, Portugal; CEBIMED, Faculty of Health Sciences, Fernando Pessoa University, Porto, Portugal.
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15
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A quantitative LumiFluo assay to test inhibitory compounds blocking p53 degradation induced by human papillomavirus oncoprotein E6 in living cells. Sci Rep 2018; 8:6020. [PMID: 29662081 PMCID: PMC5902497 DOI: 10.1038/s41598-018-24470-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Accepted: 03/29/2018] [Indexed: 12/25/2022] Open
Abstract
High-risk human papillomaviruses (HR-HPVs) are the causative agents for the onset of several epithelial cancers in humans. The deregulated expression of the viral oncoproteins E6 and E7 is the driving force sustaining the progression of malignant transformation in pre-neoplastic lesions. Targeting the viral E6 oncoprotein through inhibitory compounds can counteract the survival of cancer cells due to the reactivation of p53-mediated pathways and represents an intriguing strategy to treat HPV-associated neoplasias. Here, we describe the development of a quantitative and easy-to-perform assay to monitor the E6-mediated degradation of p53 in living cells to be used for small-molecule testing. This assay allows to unbiasedly determine whether a compound can protect p53 from the E6-mediated degradation in cells, through a simple 3-step protocol. We validated the assay by testing two small molecules, SAHA and RITA, reported to impair the E6-mediated p53 degradation. Interestingly, we observed that only SAHA efficiently rescued p53, while RITA could not provide the same degree of protection. The possibility to specifically and quantitatively monitor the ability of a selected compound to rescue p53 in a cellular context through our LumiFluo assay could represent an important step towards the successful development of anti-HPV drugs.
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16
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TRRAP is essential for regulating the accumulation of mutant and wild-type p53 in lymphoma. Blood 2018; 131:2789-2802. [PMID: 29653964 DOI: 10.1182/blood-2017-09-806679] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Accepted: 04/07/2018] [Indexed: 12/26/2022] Open
Abstract
Tumors accumulate high levels of mutant p53 (mutp53), which contributes to mutp53 gain-of-function properties. The mechanisms that underlie such excessive accumulation are not fully understood. To discover regulators of mutp53 protein accumulation, we performed a large-scale RNA interference screen in a Burkitt lymphoma cell line model. We identified transformation/transcription domain-associated protein (TRRAP), a constituent of several histone acetyltransferase complexes, as a critical positive regulator of both mutp53 and wild-type p53 levels. TRRAP silencing attenuated p53 accumulation in lymphoma and colon cancer models, whereas TRRAP overexpression increased mutp53 levels, suggesting a role for TRRAP across cancer entities and p53 mutations. Through clustered regularly interspaced short palindromic repeats (CRISPR)-Cas9 screening, we identified a 109-amino-acid region in the N-terminal HEAT repeat region of TRRAP that was crucial for mutp53 stabilization and cell proliferation. Mass spectrometric analysis of the mutp53 interactome indicated that TRRAP silencing caused degradation of mutp53 via the MDM2-proteasome axis. This suggests that TRRAP is vital for maintaining mutp53 levels by shielding it against the natural p53 degradation machinery. To identify drugs that alleviated p53 accumulation similarly to TRRAP silencing, we performed a small-molecule drug screen and found that inhibition of histone deacetylases (HDACs), specifically HDAC1/2/3, decreased p53 levels to a comparable extent. In summary, here we identify TRRAP as a key regulator of p53 levels and link acetylation-modifying complexes to p53 protein stability. Our findings may provide clues for therapeutic targeting of mutp53 in lymphoma and other cancers.
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17
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DasGupta T, Nweze EI, Yue H, Wang L, Jin J, Ghosh SK, Kawsar HI, Zender C, Androphy EJ, Weinberg A, McCormick TS, Jin G. Human papillomavirus oncogenic E6 protein regulates human β-defensin 3 (hBD3) expression via the tumor suppressor protein p53. Oncotarget 2017; 7:27430-44. [PMID: 27034006 PMCID: PMC5053661 DOI: 10.18632/oncotarget.8443] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2015] [Accepted: 03/17/2016] [Indexed: 01/24/2023] Open
Abstract
Human β-defensin-3 (hBD3) is an epithelial cell-derived innate immune regulatory molecule overexpressed in oral dysplastic lesions and fosters a tumor-promoting microenvironment. Expression of hBD3 is induced by the epidermal growth factor receptor signaling pathway. Here we describe a novel pathway through which the high-risk human papillomavirus type-16 (HPV-16) oncoprotein E6 induces hBD3 expression in mucosal keratinocytes. Ablation of E6 by siRNA induces the tumor suppressor p53 and diminishes hBD3 in HPV-16 positive CaSki cervical cancer cells and UM-SCC-104 head and neck cancer cells. Malignant cells in HPV-16-associated oropharyngeal cancer overexpress hBD3. HPV-16 E6 induces hBD3 mRNA expression, peptide production and gene promoter activity in mucosal keratinocytes. Reduction of cellular levels of p53 stimulates hBD3 expression, while activation of p53 by doxorubicin inhibits its expression in primary oral keratinocytes and CaSki cells, suggesting that p53 represses hBD3 expression. A p53 binding site in the hBD3 gene promoter has been identified by using electrophoretic mobility shift assays and chromatin immunoprecipitation (ChIP). In addition, the p63 protein isoform ΔNp63α, but not TAp63, stimulated transactivation of the hBD3 gene and was co-expressed with hBD3 in head and neck cancer specimens. Therefore, high-risk HPV E6 oncoproteins may stimulate hBD3 expression in tumor cells to facilitate tumorigenesis of HPV-associated head and neck cancer.
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Affiliation(s)
- Twishasri DasGupta
- Department of Biological Sciences, Case Western Reserve University School of Dental Medicine, Cleveland, OH, USA
| | - Emeka I Nweze
- Department of Biological Sciences, Case Western Reserve University School of Dental Medicine, Cleveland, OH, USA.,Present Address: University of Nigeria, Nsukka, Nigera
| | - Hong Yue
- Department of Biological Sciences, Case Western Reserve University School of Dental Medicine, Cleveland, OH, USA
| | - Liming Wang
- Center for Molecular Cancer Diagnosis Inc., Twinsburg, OH, USA
| | - Jessica Jin
- Human Developmental and Regenerative Biology, Harvard University, Cambridge, MA, USA
| | - Santosh K Ghosh
- Department of Biological Sciences, Case Western Reserve University School of Dental Medicine, Cleveland, OH, USA
| | - Hameem I Kawsar
- Department of Biological Sciences, Case Western Reserve University School of Dental Medicine, Cleveland, OH, USA.,Present Address: St. Luke's Hospital, Chesterfield, MO, USA
| | - Chad Zender
- Department of Otolaryngology-Head & Neck Surgery, University Hospitals Case Medical Center, Case Western Reserve University School of Medicine, Cleveland, OH, USA
| | - Elliot J Androphy
- Department of Dermatology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Aaron Weinberg
- Department of Biological Sciences, Case Western Reserve University School of Dental Medicine, Cleveland, OH, USA
| | - Thomas S McCormick
- Department of Dermatology, University Hospitals Case Medical Center, Case Western Reserve University School of Medicine, Cleveland, OH, USA
| | - Ge Jin
- Department of Biological Sciences, Case Western Reserve University School of Dental Medicine, Cleveland, OH, USA
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18
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Abstract
Cervical cancer, a potentially preventable disease, remains the second most common malignancy in women worldwide. Human papillomavirus (HPV) is the single most important etiological agent in cervical cancer, contributing to neoplastic progression through the action of viral oncoproteins, mainly E6 and E7. Cervical screening programs using Pap smear testing have dramatically improved cervical cancer incidence and reduced deaths, but cervical cancer still remains a global health burden. The biomarker discovery for accurate detection and diagnosis of cervical carcinoma and its malignant precursors (collectively referred to as high-grade cervical disease) represents one of the current challenges in clinical medicine and cytopathology.
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Affiliation(s)
- Eun-Kyoung Yim
- Department of Obstetrics and Gynecology, Catholic University Medical College, 505 Banpo-dong, Seocho-gu, Seoul, 137-040, Republic of Korea
| | - Jong-Sup Park
- Department of Obstetrics and Gynecology, Catholic University Medical College, 505 Banpo-dong, Seocho-gu, Seoul, 137-040, Republic of Korea
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19
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Poirson J, Biquand E, Straub ML, Cassonnet P, Nominé Y, Jones L, van der Werf S, Travé G, Zanier K, Jacob Y, Demeret C, Masson M. Mapping the interactome of HPV E6 and E7 oncoproteins with the ubiquitin-proteasome system. FEBS J 2017; 284:3171-3201. [PMID: 28786561 DOI: 10.1111/febs.14193] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Revised: 07/27/2017] [Accepted: 08/03/2017] [Indexed: 12/11/2022]
Abstract
Protein ubiquitination and its reverse reaction, deubiquitination, regulate protein stability, protein binding activity, and their subcellular localization. These reactions are catalyzed by the enzymes E1, E2, and E3 ubiquitin (Ub) ligases and deubiquitinases (DUBs). The Ub-proteasome system (UPS) is targeted by viruses for the sake of their replication and to escape host immune response. To identify novel partners of human papillomavirus 16 (HPV16) E6 and E7 proteins, we assembled and screened a library of 590 cDNAs related to the UPS by using the Gaussia princeps luciferase protein complementation assay. HPV16 E6 was found to bind to the homology to E6AP C terminus-type Ub ligase (E6AP), three really interesting new gene (RING)-type Ub ligases (MGRN1, LNX3, LNX4), and the DUB Ub-specific protease 15 (USP15). Except for E6AP, the binding of UPS factors did not require the LxxLL-binding pocket of HPV16 E6. LNX3 bound preferentially to all high-risk mucosal HPV E6 tested, whereas LNX4 bound specifically to HPV16 E6. HPV16 E7 was found to bind to several broad-complex tramtrack and bric-a-brac domain-containing proteins (such as TNFAIP1/KCTD13) that are potential substrate adaptors of Cullin 3-RING Ub ligases, to RING-type Ub ligases implicated in innate immunity (RNF135, TRIM32, TRAF2, TRAF5), to the substrate adaptor DCAF15 of Cullin 4-RING Ub ligase and to some DUBs (USP29, USP33). The binding to UPS factors did not require the LxCxE motif but rather the C-terminal region of HPV16 E7 protein. The identified UPS factors interacted with most of E7 proteins across different HPV types. This study establishes a strategy for the rapid identification of interactions between host or pathogen proteins and the human ubiquitination system.
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Affiliation(s)
- Juline Poirson
- Ecole Supérieure de Biotechnologie Strasbourg, UMR-7242, CNRS, Université de Strasbourg, Illkirch, France
| | - Elise Biquand
- UMR 3569, CNRS, Unité de Génétique Moléculaire des Virus à ARN, Institut Pasteur, Université Paris Diderot, Paris, France
| | - Marie-Laure Straub
- Ecole Supérieure de Biotechnologie Strasbourg, UMR-7242, CNRS, Université de Strasbourg, Illkirch, France
| | - Patricia Cassonnet
- UMR 3569, CNRS, Unité de Génétique Moléculaire des Virus à ARN, Institut Pasteur, Université Paris Diderot, Paris, France
| | - Yves Nominé
- UMR 7104-Inserm U964, CNRS, IGBMC-CBI, Equipe labellisée Ligue 2015, Illkirch, France
| | - Louis Jones
- Biostatistiques et biologie intégrative (C3BI), Institut Pasteur, Centre de bioinformatique, Paris, France
| | - Sylvie van der Werf
- UMR 3569, CNRS, Unité de Génétique Moléculaire des Virus à ARN, Institut Pasteur, Université Paris Diderot, Paris, France
| | - Gilles Travé
- UMR 7104-Inserm U964, CNRS, IGBMC-CBI, Equipe labellisée Ligue 2015, Illkirch, France
| | - Katia Zanier
- Ecole Supérieure de Biotechnologie Strasbourg, UMR-7242, CNRS, Université de Strasbourg, Illkirch, France
| | - Yves Jacob
- UMR 3569, CNRS, Unité de Génétique Moléculaire des Virus à ARN, Institut Pasteur, Université Paris Diderot, Paris, France
| | - Caroline Demeret
- UMR 3569, CNRS, Unité de Génétique Moléculaire des Virus à ARN, Institut Pasteur, Université Paris Diderot, Paris, France
| | - Murielle Masson
- Ecole Supérieure de Biotechnologie Strasbourg, UMR-7242, CNRS, Université de Strasbourg, Illkirch, France
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20
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Chand V, Nandi D, Mangla AG, Sharma P, Nag A. Tale of a multifaceted co-activator, hADA3: from embryogenesis to cancer and beyond. Open Biol 2017; 6:rsob.160153. [PMID: 27605378 PMCID: PMC5043578 DOI: 10.1098/rsob.160153] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2016] [Accepted: 08/08/2016] [Indexed: 12/19/2022] Open
Abstract
Human ADA3, the evolutionarily conserved transcriptional co-activator, remains the unified part of multiple cellular functions, including regulation of nuclear receptor functions, cell proliferation, apoptosis, senescence, chromatin remodelling, genomic stability and chromosomal maintenance. The past decade has witnessed exciting findings leading to considerable expansion in research related to the biology and regulation of hADA3. Embryonic lethality in homozygous knockout Ada3 mouse signifies the importance of this gene product during early embryonic development. Moreover, the fact that it is a novel target of Human Papillomavirus E6 oncoprotein, one of the most prevalent causal agents behind cervical cancer, helps highlight some of the crucial aspects of HPV-mediated oncogenesis. These findings imply the central involvement of hADA3 in regulation of various cellular functional losses accountable for the genesis of malignancy and viral infections. Recent reports also provide evidence for post-translational modifications of hADA3 leading to its instability and contributing to the malignant phenotype of cervical cancer cells. Furthermore, its association with poor prognosis of breast cancer suggests intimate association in the pathogenesis of the disease. Here, we present the first review on hADA3 with a comprehensive outlook on the molecular and functional roles of hADA3 to provoke further interest for more elegant and intensive studies exploring assorted aspects of this protein.
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Affiliation(s)
- Vaibhav Chand
- Department of Biochemistry, University of Delhi South Campus, New Delhi, 110021, India
| | - Deeptashree Nandi
- Department of Biochemistry, University of Delhi South Campus, New Delhi, 110021, India
| | - Anita Garg Mangla
- Department of Biochemistry, University of Delhi South Campus, New Delhi, 110021, India
| | - Puneet Sharma
- Department of Biochemistry, University of Delhi South Campus, New Delhi, 110021, India
| | - Alo Nag
- Department of Biochemistry, University of Delhi South Campus, New Delhi, 110021, India
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21
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Xu J, Fang Y, Qin J, Chen X, Liang X, Xie X, Lu W. A transcriptomic landscape of human papillomavirus 16 E6-regulated gene expression and splicing events. FEBS Lett 2016; 590:4594-4605. [PMID: 27859058 DOI: 10.1002/1873-3468.12486] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Revised: 10/12/2016] [Accepted: 10/31/2016] [Indexed: 12/12/2022]
Affiliation(s)
- Junfen Xu
- Department of Gynecologic Oncology; Women's Hospital; School of Medicine; Zhejiang University; Hangzhou China
| | - Yifeng Fang
- Department of General Surgery; Sir Run Run Shaw Hospital; School of Medicine; Zhejiang University; Hangzhou China
| | - Jiale Qin
- Department of Ultrasound; Women's Hospital; School of Medicine; Zhejiang University; Hangzhou China
| | - Xiaojing Chen
- Women's Reproductive Health Laboratory of Zhejiang Province; Women's Hospital; School of Medicine; Zhejiang University; Hangzhou China
| | - Xiao Liang
- Department of General Surgery; Sir Run Run Shaw Hospital; School of Medicine; Zhejiang University; Hangzhou China
| | - Xing Xie
- Department of Gynecologic Oncology; Women's Hospital; School of Medicine; Zhejiang University; Hangzhou China
| | - Weiguo Lu
- Department of Gynecologic Oncology; Women's Hospital; School of Medicine; Zhejiang University; Hangzhou China
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22
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Griffin NI, Sharma G, Zhao X, Mirza S, Srivastava S, Dave BJ, Aleskandarany M, Rakha E, Mohibi S, Band H, Band V. ADA3 regulates normal and tumor mammary epithelial cell proliferation through c-MYC. Breast Cancer Res 2016; 18:113. [PMID: 27852327 PMCID: PMC5112670 DOI: 10.1186/s13058-016-0770-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Accepted: 10/13/2016] [Indexed: 02/06/2023] Open
Abstract
Background We have established the critical role of ADA3 as a coactivator of estrogen receptor (ER), as well as its role in cell cycle progression. Furthermore, we showed that ADA3 is predominantly nuclear in mammary epithelium, and in ER+, but is cytoplasmic in ER- breast cancers, the latter correlating with poor survival. However, the role of nuclear ADA3 in human mammary epithelial cells (hMECs), and in ER+ breast cancer cells, as well as the importance of ADA3 expression in relation to patient prognosis and survival in ER+ breast cancer have remained uncharacterized. Methods We overexpressed ADA3 in hMECs or in ER+ breast cancer cells and assessed the effect on cell proliferation. The expression of ADA3 was analyzed then correlated with the expression of various prognostic markers, as well as survival of breast cancer patients. Results Overexpression of ADA3 in ER- hMECs as well as in ER+ breast cancer cell lines enhanced cell proliferation. These cells showed increased cyclin B and c-MYC, decreased p27 and increased SKP2 levels. This was accompanied by increased mRNA levels of early response genes c-FOS, EGR1, and c-MYC. Analysis of breast cancer tissue specimens showed a significant correlation of ADA3 nuclear expression with c-MYC expression. Furthermore, nuclear ADA3 and c-MYC expression together showed significant correlation with tumor grade, mitosis, pleomorphism, NPI, ER/PR status, Ki67 and p27 expression. Importantly, within ER+ cases, expression of nuclear ADA3 and c-MYC also significantly correlated with Ki67 and p27 expression. Univariate Kaplan Meier analysis of four groups in the whole, as well as the ER+ patients showed that c-MYC and ADA3 combinatorial phenotypes showed significantly different breast cancer specific survival with c-MYC-high and ADA3-Low subgroup had the worst outcome. Using multivariate analyses within the whole cohort and the ER+ subgroups, the significant association of ADA3 and c-MYC expression with patients’ outcome was independent of tumor grade, stage and size, and ER status. Conclusion ADA3 overexpression enhances cell proliferation that is associated with increased expression of c-MYC. Expression patterns with respect to ADA3/c-MYC can divide patients into four significantly different subgroups, with c-MYC High and ADA3 Low status independently predicting poor survival in patients. Electronic supplementary material The online version of this article (doi:10.1186/s13058-016-0770-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Nicolas I Griffin
- Departments of Genetics, Cell Biology and Anatomy, University of Nebraska Medical Center, 985805 Nebraska Medical Center, Omaha, NE, 68198, USA
| | - Gayatri Sharma
- Departments of Genetics, Cell Biology and Anatomy, University of Nebraska Medical Center, 985805 Nebraska Medical Center, Omaha, NE, 68198, USA
| | - Xiangshan Zhao
- Departments of Genetics, Cell Biology and Anatomy, University of Nebraska Medical Center, 985805 Nebraska Medical Center, Omaha, NE, 68198, USA
| | - Sameer Mirza
- Departments of Genetics, Cell Biology and Anatomy, University of Nebraska Medical Center, 985805 Nebraska Medical Center, Omaha, NE, 68198, USA
| | - Shashank Srivastava
- Departments of Genetics, Cell Biology and Anatomy, University of Nebraska Medical Center, 985805 Nebraska Medical Center, Omaha, NE, 68198, USA
| | - Bhavana J Dave
- Departments of Genetics, Cell Biology and Anatomy, University of Nebraska Medical Center, 985805 Nebraska Medical Center, Omaha, NE, 68198, USA.,Departments of Human Genetics Laboratories, Munroe Meyer Institute for Genetics and Rehabilitation, University of Nebraska Medical Center, 985805 Nebraska Medical Center, Omaha, NE, 68198, USA.,Departments of Pathology & Microbiology, College of Medicine, University of Nebraska Medical Center, 985805 Nebraska Medical Center, Omaha, NE, 68198, USA
| | - Mohammed Aleskandarany
- School of Molecular Medical Sciences and Cellular Pathology, University of Nottingham and Nottingham University Hospital, Nottingham City Hospital, Hucknall Road, Nottingham, NG5 1PB, USA
| | - Emad Rakha
- School of Molecular Medical Sciences and Cellular Pathology, University of Nottingham and Nottingham University Hospital, Nottingham City Hospital, Hucknall Road, Nottingham, NG5 1PB, USA
| | - Shakur Mohibi
- Departments of Genetics, Cell Biology and Anatomy, University of Nebraska Medical Center, 985805 Nebraska Medical Center, Omaha, NE, 68198, USA
| | - Hamid Band
- Departments of Genetics, Cell Biology and Anatomy, University of Nebraska Medical Center, 985805 Nebraska Medical Center, Omaha, NE, 68198, USA.,Departments of Pathology & Microbiology, College of Medicine, University of Nebraska Medical Center, 985805 Nebraska Medical Center, Omaha, NE, 68198, USA.,Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, 985805 Nebraska Medical Center, Omaha, NE, 68198, USA.,Fred & Pamela Buffett Cancer Center, University of Nebraska Medical Center, 985805 Nebraska Medical Center, Omaha, NE, 68198, USA
| | - Vimla Band
- Departments of Genetics, Cell Biology and Anatomy, University of Nebraska Medical Center, 985805 Nebraska Medical Center, Omaha, NE, 68198, USA. .,Fred & Pamela Buffett Cancer Center, University of Nebraska Medical Center, 985805 Nebraska Medical Center, Omaha, NE, 68198, USA.
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Proteomic analysis of the gamma human papillomavirus type 197 E6 and E7 associated cellular proteins. Virology 2016; 500:71-81. [PMID: 27771561 DOI: 10.1016/j.virol.2016.10.010] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2016] [Revised: 10/07/2016] [Accepted: 10/12/2016] [Indexed: 12/26/2022]
Abstract
Gamma HPV197 was the most frequently identified HPV when human skin cancer specimens were analyzed by deep sequencing (Arroyo Muhr et al., Int. J. Cancer 136: 2546-55, 2015). To gain insight into the biological activities of HPV197, we investigated the cellular interactomes of HPV197 E6 and E7. HPV197 E6 protein interacts with a broad spectrum of cellular LXXLL domain proteins, including UBE3A and MAML1. HPV197 E6 also binds and inhibits the TP53 tumor suppressor and interacts with the CCR4-NOT ubiquitin ligase and deadenylation complex. Despite lacking a canonical retinoblastoma (RB1) tumor suppressor binding site, HPV197 E7 binds RB1 and activates E2F transcription. Hence, HPV197 E6 and E7 proteins interact with a similar set of cellular proteins as E6 and E7 proteins encoded by HPVs that have been linked to human carcinogenesis and/or have transforming activities in vitro.
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24
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Acetylation of Mammalian ADA3 Is Required for Its Functional Roles in Histone Acetylation and Cell Proliferation. Mol Cell Biol 2016; 36:2487-502. [PMID: 27402865 PMCID: PMC5021379 DOI: 10.1128/mcb.00342-16] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2016] [Accepted: 06/30/2016] [Indexed: 12/16/2022] Open
Abstract
Alteration/deficiency in activation 3 (ADA3) is an essential component of specific histone acetyltransferase (HAT) complexes. We have previously shown that ADA3 is required for establishing global histone acetylation patterns and for normal cell cycle progression (S. Mohibi et al., J Biol Chem 287:29442-29456, 2012, http://dx.doi.org/10.1074/jbc.M112.378901). Here, we report that these functional roles of ADA3 require its acetylation. We show that ADA3 acetylation, which is dynamically regulated in a cell cycle-dependent manner, reflects a balance of coordinated actions of its associated HATs, GCN5, PCAF, and p300, and a new partner that we define, the deacetylase SIRT1. We use mass spectrometry and site-directed mutagenesis to identify major sites of ADA3 acetylated by GCN5 and p300. Acetylation-defective mutants are capable of interacting with HATs and other components of HAT complexes but are deficient in their ability to restore ADA3-dependent global or locus-specific histone acetylation marks and cell proliferation in Ada3-deleted murine embryonic fibroblasts (MEFs). Given the key importance of ADA3-containing HAT complexes in the regulation of various biological processes, including the cell cycle, our study presents a novel mechanism to regulate the function of these complexes through dynamic ADA3 acetylation.
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25
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Chaloob MK, Hussein AG, Qasim BJ. Correlation of P16 (Ink4a) and CK17 to HPV (16E6+18E6) in Premalignant and Malignant Lesions of Uterine Cervix: A Clinicopathologic Study. IRANIAN JOURNAL OF PATHOLOGY 2016; 11:377-390. [PMID: 28855930 PMCID: PMC5563936] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
BACKGROUND This research was accomplished to evaluate the IHC expression of p16 (ink4a) and CK17 in low grade cervical intraepithelial lesions (LSIL), high grade cervical intraepithelial lesions (HSIL) and invasive cervical carcinomas and to assess their correlation to HPV (16E6+18E6). METHODS The study included (127) formalin-fixed paraffin-embedded cervical biopsies; of which 22 cases were chronic cervicitis, 24 cases were LSIL, 28 cases were HSIL and 53 cases were invasive cervical carcinomas. Sections were immunohistochemically stained for p16 (ink4a), CK17 and HPV (16E6+18E6). RESULTS The study established a highly significant increase in IHC of expression of p16 (ink4a), CK17 and HPV (16E6+18E6) from LSIL through HSIL to invasive carcinomas (P-value˂0.001). There was non-significant association between IHC expression of all makers with age of patients; types, grade and stage of cervical carcinomas (P-value˃0.05). HPV (16E6+18E6) revealed a significantly positive correlation with p16 (ink4a) (P-value˂0.05) and a non- significant correlation with CK17 (P-value˃0.05); in LSIL, HSIL and invasive carcinoma cases. CONCLUSION p16 (ink4a) expression directly reflects infection with high risk HPV in cervical lesions and can add a significant diagnostic accuracy in the evaluation of CIN. CK 17 is a good marker of malignant transformation, with increasing in its expression according to the severity of cervical lesions; however, it is not related to HPV infection. Both markers are not related to prognostic variables of patients with cervical carcinoma.
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Affiliation(s)
| | - Alaa G. Hussein
- Dept. of Pathology and Forensic medicine, College of Medicine, Al-Nahrain University, Baghdad, Iraq
| | - Ban J. Qasim
- Dept. of Pathology and Forensic medicine, College of Medicine, Al-Nahrain University, Baghdad, Iraq
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Abstract
Human papillomaviruses (HPVs) infect the epidermis as well as mucous membranes of humans. They are the causative agents of anogenital tract and some oropharyngeal cancers. Infections begin in the basal epithelia, where the viral genome replicates slowly along with its host cell. As infected cells begin to differentiate and progress toward the periphery, the virus drives proliferation in cells that would otherwise be quiescent. To uncouple differentiation from continued cellular propagation, HPVs express two oncoproteins, HPV E6 and E7. This review focuses on high-risk α-HPV E6, which in addition to supporting viral replication has transforming properties. HPV E6 promotes p53 degradation and activates telomerase, but the multifaceted oncoprotein has numerous other functions that are highlighted here.
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Affiliation(s)
- Nicholas A Wallace
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109;
| | - Denise A Galloway
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109;
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Erives AJ. Genes conserved in bilaterians but jointly lost with Myc during nematode evolution are enriched in cell proliferation and cell migration functions. Dev Genes Evol 2015; 225:259-73. [PMID: 26173873 PMCID: PMC4568025 DOI: 10.1007/s00427-015-0508-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2015] [Accepted: 06/24/2015] [Indexed: 12/11/2022]
Abstract
Animals use a stereotypical set of developmental genes to build body architectures of varying sizes and organizational complexity. Some genes are critical to developmental patterning, while other genes are important to physiological control of growth. However, growth regulator genes may not be as important in small-bodied “micro-metazoans” such as nematodes. Nematodes use a simplified developmental strategy of lineage-based cell fate specifications to produce an adult bilaterian body composed of a few hundreds of cells. Nematodes also lost the MYC proto-oncogenic regulator of cell proliferation. To identify additional regulators of cell proliferation that were lost with MYC, we computationally screened and determined 839 high-confidence genes that are conserved in bilaterians/lost in nematodes (CIBLIN genes). We find that 30 % of all CIBLIN genes encode transcriptional regulators of cell proliferation, epithelial-to-mesenchyme transitions, and other processes. Over 50 % of CIBLIN genes are unnamed genes in Drosophila, suggesting that there are many understudied genes. Interestingly, CIBLIN genes include many Myc synthetic lethal (MycSL) hits from recent screens. CIBLIN genes include key regulators of heparan sulfate proteoglycan (HSPG) sulfation patterns, and lysyl oxidases involved in cross-linking and modification of the extracellular matrix (ECM). These genes and others suggest the CIBLIN repertoire services critical functions in ECM remodeling and cell migration in large-bodied bilaterians. Correspondingly, CIBLIN genes are co-expressed with Myc in cancer transcriptomes, and include a preponderance of known determinants of cancer progression and tumor aggression. We propose that CIBLIN gene research can improve our understanding of regulatory control of cellular growth in metazoans.
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Affiliation(s)
- Albert J Erives
- Department of Biology, University of Iowa, Iowa City, IA, 52242-1324, USA.
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Immune Escape and Immunotherapy of HPV-Related Oropharyngeal Cancer: Has the Future Arrived? CURRENT OTORHINOLARYNGOLOGY REPORTS 2015. [DOI: 10.1007/s40136-015-0079-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Tornesello ML, Perri F, Buonaguro L, Ionna F, Buonaguro FM, Caponigro F. HPV-related oropharyngeal cancers: From pathogenesis to new therapeutic approaches. Cancer Lett 2014; 351:198-205. [PMID: 24971935 DOI: 10.1016/j.canlet.2014.06.003] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2014] [Revised: 05/08/2014] [Accepted: 06/04/2014] [Indexed: 01/07/2023]
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Habbous S, Pang V, Xu W, Amir E, Liu G. Human papillomavirus and host genetic polymorphisms in carcinogenesis: a systematic review and meta-analysis. J Clin Virol 2014; 61:220-9. [PMID: 25174543 DOI: 10.1016/j.jcv.2014.07.019] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2014] [Revised: 07/26/2014] [Accepted: 07/30/2014] [Indexed: 11/28/2022]
Abstract
BACKGROUND As the role of human papillomavirus (HPV) in carcinogenesis continues to rise, the role of genetic factors that modify this risk have become increasingly important. In this study, we reviewed the literature for associations between polymorphisms and HPV in carcinogenesis. OBJECTIVE To identify any associations of genetic polymorphisms with oncogenic HPV in carcinogenesis and to evaluate the methodology used. STUDY DESIGN Systematic literature review of HPV, genetic polymorphisms, and cancer risk. Odds ratios (OR), interaction terms, and p-values were tabulated. Meta-analyses and measures of heterogeneity were estimated using RevMan 5.1. RESULTS The cervix was the most frequently studied cancer site followed by the head and neck. Overall risk of cancer (cancer vs. control) was the most common comparison, whereas reports of initiation (pre-cancer vs. control) and progression (cancer vs. pre-cancer) were rare. Case-series and joint-effect of HPV and genotype on risk was evaluated frequently, but the independent effect of either risk factor alone was rarely provided. P53-Arg72Pro was the most commonly studied polymorphism studied. No consistent interaction was detected by meta-analysis in the HPV(+) [OR 0.98 (0.55-1.76)] or the HPV(-) [OR 1.10 (0.76-1.60)] subsets in head and neck cancer risk. Polymorphisms in genes known to encode proteins that physically interact with HPV were infrequently studied. CONCLUSION No consistent polymorphism-HPV interactions were observed. Study design, choice of candidate polymorphisms/genes, and a focus on overall risk rather than any specific portions of the carcinogenic pathway may have contributed to lack of significant findings.
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Affiliation(s)
- Steven Habbous
- Ontario Cancer Institute, Princess Margaret Cancer Centre, Toronto, Ontario, Canada M5G 2M9
| | - Vincent Pang
- Ontario Cancer Institute, Princess Margaret Cancer Centre, Toronto, Ontario, Canada M5G 2M9
| | - Wei Xu
- Ontario Cancer Institute, Princess Margaret Cancer Centre, Toronto, Ontario, Canada M5G 2M9; Department of Biostatistics, Princess Margaret Cancer Centre, Toronto, Ontario, Canada M5G 2M9
| | - Eitan Amir
- Ontario Cancer Institute, Princess Margaret Cancer Centre, Toronto, Ontario, Canada M5G 2M9; Division of Medical Oncology and Hematology, Toronto, Ontario, Canada M5G 2M9
| | - Geoffrey Liu
- Ontario Cancer Institute, Princess Margaret Cancer Centre, Toronto, Ontario, Canada M5G 2M9; Medicine and Epidemiology, Dalla Lana School of Public Health, University of Toronto, Canada M5G 2M9.
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Chand V, John R, Jaiswal N, Johar SS, Nag A. High-risk HPV16E6 stimulates hADA3 degradation by enhancing its SUMOylation. Carcinogenesis 2014; 35:1830-9. [DOI: 10.1093/carcin/bgu104] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
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PinX1, a novel target gene of p53, is suppressed by HPV16 E6 in cervical cancer cells. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2014; 1839:88-96. [PMID: 24412852 DOI: 10.1016/j.bbagrm.2014.01.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2013] [Revised: 12/27/2013] [Accepted: 01/02/2014] [Indexed: 01/14/2023]
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A functional genomics screen identifies PCAF and ADA3 as regulators of human granzyme B-mediated apoptosis and Bid cleavage. Cell Death Differ 2014; 21:748-60. [PMID: 24464226 DOI: 10.1038/cdd.2013.203] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2013] [Revised: 12/15/2013] [Accepted: 12/16/2013] [Indexed: 12/24/2022] Open
Abstract
The human lymphocyte toxins granzyme B (hGrzB) and perforin cooperatively induce apoptosis of virus-infected or transformed cells: perforin pores enable entry of the serine protease hGrzB into the cytosol, where it processes Bid to selectively activate the intrinsic apoptosis pathway. Truncated Bid (tBid) induces Bax/Bak-dependent mitochondrial outer membrane permeability and the release of cytochrome c and Smac/Diablo. To identify cellular proteins that regulate perforin/hGrzB-mediated Bid cleavage and subsequent apoptosis, we performed a gene-knockdown (KD) screen using a lentiviral pool of short hairpin RNAs embedded within a miR30 backbone (shRNAmiR). We transduced HeLa cells with a lentiviral pool expressing shRNAmiRs that target 1213 genes known to be involved in cell death signaling and selected cells with acquired resistance to perforin/hGrzB-mediated apoptosis. Twenty-two shRNAmiRs were identified in the positive-selection screen including two, PCAF and ADA3, whose gene products are known to reside in the same epigenetic regulatory complexes. Small interfering (si)RNA-mediated gene-KD of PCAF or ADA3 also conferred resistance to perforin/hGrzB-mediated apoptosis providing independent validation of the screen results. Mechanistically, PCAF and ADA3 exerted their pro-apoptotic effect upstream of mitochondrial membrane permeabilization, as indicated by reduced cytochrome c release in PCAF-KD cells exposed to perforin/hGrzB. While overall levels of Bid were unaltered, perforin/hGrzB-mediated cleavage of Bid was reduced in PCAF-KD or ADA3-KD cells. We discovered that PCAF-KD or ADA3-KD resulted in reduced expression of PACS2, a protein implicated in Bid trafficking to mitochondria and importantly, targeted PACS2-KD phenocopied the effect of PCAF-KD or ADA3-KD. We conclude that PCAF and ADA3 regulate Bid processing via PACS2, to modulate the mitochondrial cell death pathway in response to hGrzB.
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Manipulation of cellular DNA damage repair machinery facilitates propagation of human papillomaviruses. Semin Cancer Biol 2014; 26:30-42. [PMID: 24412279 DOI: 10.1016/j.semcancer.2013.12.003] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2013] [Revised: 12/05/2013] [Accepted: 12/18/2013] [Indexed: 01/08/2023]
Abstract
In general, the interplay among viruses and DNA damage repair (DDR) pathways can be divided based on whether the interaction promotes or inhibits the viral lifecycle. The propagation of human papillomaviruses is both promoted and inhibited by DDR proteins. As a result, HPV proteins both activate repair pathways, such as the ATM and ATR pathways, and inhibit other pathways, most notably the p53 signaling pathway. Indeed, the role of HPV proteins, with regard to the DDR pathways, can be divided into two broad categories. The first set of viral proteins, HPV E1 and E2 activate a DNA damage response and recruit repair proteins to viral replication centers, where these proteins are likely usurped to replicate the viral genome. Because the activation of the DDR response typically elicits a cell cycle arrest that would impeded the viral lifecycle, the second set of HPV proteins, HPV E6 and E7, prevents the DDR response from pausing cell cycle progression or inducing apoptosis. This review provides a detailed account of the interactions among HPV proteins and DDR proteins that facilitate HPV propagation.
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Mizianty MJ, Uversky V, Kurgan L. Prediction of intrinsic disorder in proteins using MFDp2. Methods Mol Biol 2014; 1137:147-62. [PMID: 24573480 DOI: 10.1007/978-1-4939-0366-5_11] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Intrinsically disordered proteins (IDPs) are either entirely disordered or contain disordered regions in their native state. IDPs were found to be abundant across all kingdoms of life, particularly in eukaryotes, and are implicated in numerous cellular processes. Experimental annotation of disorder lags behind the rapidly growing sizes of the protein databases and thus computational methods are used to close this gap and to investigate the disorder. MFDp2 is a novel webserver for accurate sequence-based prediction of protein disorder which also outputs well-described sequence-derived information that allows profiling the predicted disorder. We conveniently visualize sequence conservation, predicted secondary structure, relative solvent accessibility, and alignments to chains with annotated disorder. The webserver allows predictions for multiple proteins at the same time, includes help pages and tutorial, and the results can be downloaded as text-based (parsable) file. MFDp2 is freely available at http://biomine.ece.ualberta.ca/MFDp2/.
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Affiliation(s)
- Marcin J Mizianty
- Department of Electrical and Computer Engineering, University of Alberta, Edmonton, Canada
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Jiang P, Yue Y. Human papillomavirus oncoproteins and apoptosis (Review). Exp Ther Med 2013; 7:3-7. [PMID: 24348754 PMCID: PMC3860870 DOI: 10.3892/etm.2013.1374] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2013] [Accepted: 10/21/2013] [Indexed: 12/22/2022] Open
Abstract
The aim of this study was to review the literature and identify the association between human papillomavirus (HPV) oncoproteins and apoptosis. HPV-associated apoptosis may be primarily blocked by a number of oncoproteins, including E5, E6 and E7. E5 protein protects cells from tumor necrosis factor-associated apoptosis; the oncoprotein E6 predominantly inhibits apoptosis through the p53 pathway; and oncoprotein E7 is involved in apoptosis activation and inhibition. In addition, HPV oncoproteins are involved in activating or repressing the transcription of E6/E7. In conclusion, HPV oncoproteins, including E5, E6 and E7 protein, may interfere with apoptosis via certain regulatory principles.
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Affiliation(s)
- Peiyue Jiang
- Department of Gynecological Oncology, First Hospital of Jilin University, Changchun, Jilin 130021, P.R. China
| | - Ying Yue
- Department of Gynecological Oncology, First Hospital of Jilin University, Changchun, Jilin 130021, P.R. China
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Bai R, Li D, Shi Z, Fang X, Ge W, Zheng S. Clinical significance of Ankyrin repeat domain 12 expression in colorectal cancer. JOURNAL OF EXPERIMENTAL & CLINICAL CANCER RESEARCH : CR 2013; 32:35. [PMID: 23718802 PMCID: PMC3689078 DOI: 10.1186/1756-9966-32-35] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/11/2013] [Accepted: 05/14/2013] [Indexed: 12/22/2022]
Abstract
Background Ankyrin repeat domain 12 (ANKRD12), is encoding a 224 kDa nuclear protein and most conserved at its N-terminal ankyrin repeats region and the C-terminal co-activator interacting domain. The aim of this study was to investigate the ANKRD12 mRNA expression in colorectal cancer (CRC) tumor tissues and the normal adjacent mucosa and its potential relevance to clinicopathological characteristics and prognosis. Methods Surgical specimens of tumor tissues (n = 68) and adjacent normal mucosa (n = 51) were obtained from CRC patients. The ANKRD12 mRNA expression was measured by quantitative real time reverse transcriptase polymerase chain reaction. The relationship between ANKRD12 mRNA expression and clinicopathological features was analyzed by appropriate statistics. Kaplan–Meier analysis and Cox proportional hazards regression models were used to investigate the correlation between ANKRD12 expression and prognosis of CRC patients. Results The relative mRNA expression of ANKRD12 were significantly lower in CRC tumor tissues than in the normal adjacent mucosa (P < 0.001), and the cases with low ANKRD12 expression showed a higher frequency of liver metastasis (P = 0.015). Kaplan–Meier analysis indicated that patients (CRC without liver metastasis) with low ANKRD12 expression had poor overall survival (P = 0.041). Multivariate analysis showed that low ANKRD12 expression was an independent predictor of overall survival. Conclusion This study revealed that ANKRD12 mRNA were down regulated in CRC tumor tissues and low ANKRD12 expression was correlated with liver metastasis and poor survival of CRC patients.
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Vande Pol SB, Klingelhutz AJ. Papillomavirus E6 oncoproteins. Virology 2013; 445:115-37. [PMID: 23711382 DOI: 10.1016/j.virol.2013.04.026] [Citation(s) in RCA: 248] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2013] [Revised: 04/22/2013] [Accepted: 04/25/2013] [Indexed: 02/07/2023]
Abstract
Papillomaviruses induce benign and malignant epithelial tumors, and the viral E6 oncoprotein is essential for full transformation. E6 contributes to transformation by associating with cellular proteins, docking on specific acidic LXXLL peptide motifs found on these proteins. This review examines insights from recent studies of human and animal E6 proteins that determine the three-dimensional structure of E6 when bound to acidic LXXLL peptides. The structure of E6 is related to recent advances in the purification and identification of E6 associated protein complexes. These E6 protein-complexes, together with other proteins that bind to E6, alter a broad array of biological outcomes including modulation of cell survival, cellular transcription, host cell differentiation, growth factor dependence, DNA damage responses, and cell cycle progression.
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Affiliation(s)
- Scott B Vande Pol
- Department of Pathology, University of Virginia, Charlottesville, VA 22901, USA.
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Identification of transcriptional and phosphatase regulators as interaction partners of human ADA3, a component of histone acetyltransferase complexes. Biochem J 2013; 450:311-20. [PMID: 23167988 DOI: 10.1042/bj20120452] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
ADA (alteration/deficiency in activation) 3 is a conserved component of several transcriptional adaptor and HAT (histone acetyltransferase) complexes that regulate RNA polymerase II-mediated gene expression. Within the HAT complexes ADA3 is associated with ADA2 and the HAT GCN5 (general control non-repressed 5). ADA3 plays roles in diverse cellular processes and also in malignancies by modulating GCN5 catalytic activity and/or by interactions with other regulators. To gain a better understanding of ADA3 function, we used a yeast two-hybrid approach to screen a human fetal cDNA library for proteins that interacted with hADA3 (human ADA3). We identified three novel hADA3-interacting partners, a transcriptional regulator, AATF (apoptosis-antagonizing transcription factor), and regulatory subunits of the PP1 (protein phosphatase 1) and PP2A (protein phosphatase 2A) [PPP1R7 (PP1 regulatory subunit 7) and PPP2R5D (PP2A 56 kDa regulatory subunit δ isoform) respectively]. Analysis of truncated versions of hADA3 indicated that the C-terminal ADA2-interacting domain was not required for these interactions. Fluorescent microscopy analysis and co-immunoprecipitation provided support for the co-localization and interaction of hADA3 with these proteins in human cells. Expression of the interacting proteins altered expression of an hADA3-regulated reporter gene, suggesting functional consequences for the interactions. The detected interactions of hADA3 might extend the spectrum of mechanisms by which ADA3 can contribute to the regulation of gene expression and shed light on processes mediated by these newly identified ADA3 partners.
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HPV-18 E6 mutants reveal p53 modulation of viral DNA amplification in organotypic cultures. Proc Natl Acad Sci U S A 2013; 110:7542-9. [PMID: 23572574 DOI: 10.1073/pnas.1304855110] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Human papillomaviruses (HPVs) amplify in differentiated strata of a squamous epithelium. The HPV E7 protein destabilizes the p130/retinoblastoma susceptibility protein family of tumor suppressors and reactivates S-phase reentry, thereby facilitating viral DNA amplification. The high-risk HPV E6 protein destabilizes the p53 tumor suppressor and many other host proteins. However, the critical E6 targets relevant to viral DNA amplification have not been identified, because functionally significant E6 mutants are not stably maintained in transfected cells. Using Cre-loxP recombination, which efficiently generates HPV genomic plasmids in transfected primary human keratinocytes, we have recapitulated a highly productive infection of HPV-18 in organotypic epithelial cultures. By using this system, we now report the characterization of four HPV-18 E6 mutations. An E6 null mutant accumulated high levels of p53 and amplified very poorly. p53 siRNA or ectopic WT E6 partially restored amplification, whereas three missense E6 mutations that did not effectively destabilize p53 complemented the null mutant poorly. Unexpectedly, in cis, two of the missense mutants amplified, albeit to a lower extent than the WT and only in cells with undetectable p53. These observations and others implicate p53 and additional host proteins in regulating viral DNA amplification and also suggest an inhibitory effect of E6 overexpression. We show that high levels of viral DNA amplification are critical for late protein expression and report several previously undescribed viral RNAs, including bicistronic transcripts predicted to encode E5 and L2 or an alternative form of E1^E4 and L1.
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Jackson R, Togtema M, Zehbe I. Subcellular localization and quantitation of the human papillomavirus type 16 E6 oncoprotein through immunocytochemistry detection. Virology 2013; 435:425-32. [DOI: 10.1016/j.virol.2012.09.032] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2012] [Revised: 09/11/2012] [Accepted: 09/26/2012] [Indexed: 11/28/2022]
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Cai Q, Lv L, Shao Q, Li X, Dian A. Human papillomavirus early proteins and apoptosis. Arch Gynecol Obstet 2012; 287:541-8. [PMID: 23263171 DOI: 10.1007/s00404-012-2665-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2012] [Accepted: 11/27/2012] [Indexed: 11/26/2022]
Abstract
INTRODUCTION The human papillomavirus (HPV) associated apoptosis can be primarily attributed to some early proteins, such as E2, E5, E6, E7, and so on. Though these proteins have a low molecular size, they are capable to interact with a series of host cellular regulation proteins to induce or inhibit apoptosis. The oncoproteins E6 can inhibit the apoptosis mainly through p53 pathway. The E5 protein can protect cells from tumor necrosis factor-related apoptosis. The protein E2 protein have regulatory functions in viral transcription and induction of apoptosis. The oncoprotein E7 plays the role in both apoptosis activation and inhibition. In addition, the HPV full-length E2 proteins involve in activating or repressing the transcription of E6/E7, so as to regulating the apoptosis caused by E6 and E7. MATERIALS AND METHODS We search major databases (such as Elsevier) with the following selection criteria: HPV, early protein, apoptosis. CONCLUSIONS In this review, we summary the literature related with E2, E5, E6, and E7 proteins, and describe the regulatory principles and specific mechanism by which HPV early proteins can interfere with apoptosis and trigger gynaecopathias for women.
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Affiliation(s)
- Qiong Cai
- Department of Obstetrics and Gynecology, First People's Hospital of Yunnan Province, Kunming 650032, Yunnan, People's Republic of China
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Mirza S, Katafiasz BJ, Kumar R, Wang J, Mohibi S, Jain S, Gurumurthy CB, Pandita TK, Dave BJ, Band H, Band V. Alteration/deficiency in activation-3 (Ada3) plays a critical role in maintaining genomic stability. Cell Cycle 2012; 11:4266-74. [PMID: 23095635 PMCID: PMC3524221 DOI: 10.4161/cc.22613] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Cell cycle regulation and DNA repair following damage are essential for maintaining genome integrity. DNA damage activates checkpoints in order to repair damaged DNA prior to exit to the next phase of cell cycle. Recently, we have shown the role of Ada3, a component of various histone acetyltransferase complexes, in cell cycle regulation, and loss of Ada3 results in mouse embryonic lethality. Here, we used adenovirus-Cre-mediated Ada3 deletion in Ada3(fl/fl) mouse embryonic fibroblasts (MEFs) to assess the role of Ada3 in DNA damage response following exposure to ionizing radiation (IR). We report that Ada3 depletion was associated with increased levels of phospho-ATM (pATM), γH2AX, phospho-53BP1 (p53BP1) and phospho-RAD51 (pRAD51) in untreated cells; however, radiation response was intact in Ada3(-/-) cells. Notably, Ada3(-/-) cells exhibited a significant delay in disappearance of DNA damage foci for several critical proteins involved in the DNA repair process. Significantly, loss of Ada3 led to enhanced chromosomal aberrations, such as chromosome breaks, fragments, deletions and translocations, which further increased upon DNA damage. Notably, the total numbers of aberrations were more clearly observed in S-phase, as compared with G₁ or G₂ phases of cell cycle with IR. Lastly, comparison of DNA damage in Ada3(fl/fl) and Ada3(-/-) cells confirmed higher residual DNA damage in Ada3(-/-) cells, underscoring a critical role of Ada3 in the DNA repair process. Taken together, these findings provide evidence for a novel role for Ada3 in maintenance of the DNA repair process and genomic stability.
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Affiliation(s)
- Sameer Mirza
- Department of Genetics, Cell Biology and Anatomy, University of Nebraska Medical Center, Omaha, NE, USA
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Zhang G, Liu Y, Yu L, Sun L. GFP/HPV-16E6 fusion protein induces apoptosis in MCF-7 and 293T cells using a transient expression system. Oncol Rep 2012; 28:1673-80. [PMID: 22922869 DOI: 10.3892/or.2012.1976] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2012] [Accepted: 07/17/2012] [Indexed: 01/10/2023] Open
Abstract
Since mucosal high-risk human papillomavirus (HPV) E6 can target and degrade the tumor suppressor p53, it is recognized as a major causative agent of cervical cancer. However, to date the distribution of high-risk HPV-E6 protein remains elusive. Thus, in the present study we used a mammalian green fluorescent protein (GFP) expression system to express a GFP/HPV-16E6 fusion protein (GFP-16E6) in wild-type (wt) p53 cells, such as MCF-7 and 293T cells to investigate the trafficking and localization of E6 and p53. Following transfection, we observed that the overexpressed GFP-16E6 was a nuclear protein, and that endogenous wt p53 localized to the nucleus together with GFP-16E6. Strikingly, p53 levels were not decreased but increased in 24 h transfected with pGFP-16E6. Furthermore, we observed significant apoptosis induced by GFP-16E6, which proved to be dependent on p53 expression.
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Affiliation(s)
- Ge Zhang
- Beijing Haidian Hospital, Beijing 100080, PR China
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Mohibi S, Gurumurthy CB, Nag A, Wang J, Mirza S, Mian Y, Quinn M, Katafiasz B, Eudy J, Pandey S, Guda C, Naramura M, Band H, Band V. Mammalian alteration/deficiency in activation 3 (Ada3) is essential for embryonic development and cell cycle progression. J Biol Chem 2012; 287:29442-56. [PMID: 22736770 DOI: 10.1074/jbc.m112.378901] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Ada3 protein is an essential component of histone acetyl transferase containing coactivator complexes conserved from yeast to human. We show here that germline deletion of Ada3 in mouse is embryonic lethal, and adenovirus-Cre mediated conditional deletion of Ada3 in Ada3(FL/FL) mouse embryonic fibroblasts leads to a severe proliferation defect which was rescued by ectopic expression of human Ada3. A delay in G(1) to S phase of cell cycle was also seen that was due to accumulation of Cdk inhibitor p27 which was an indirect effect of c-myc gene transcription control by Ada3. We further showed that this defect could be partially reverted by knocking down p27. Additionally, drastic changes in global histone acetylation and changes in global gene expression were observed in microarray analyses upon loss of Ada3. Lastly, formation of abnormal nuclei, mitotic defects and delay in G(2)/M to G(1) transition was seen in Ada3 deleted cells. Taken together, we provide evidence for a critical role of Ada3 in embryogenesis and cell cycle progression as an essential component of HAT complex.
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Affiliation(s)
- Shakur Mohibi
- Department of Genetics, Cell Biology, and Anatomy, University of Nebraska Medical Center, Omaha, NE 68198-5805, USA
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Huang J, Zhang L, Liu W, Liao Q, Shi T, Xiao L, Hu F, Qiu X. CCDC134 interacts with hADA2a and functions as a regulator of hADA2a in acetyltransferase activity, DNA damage-induced apoptosis and cell cycle arrest. Histochem Cell Biol 2012; 138:41-55. [PMID: 22644376 DOI: 10.1007/s00418-012-0932-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/03/2012] [Indexed: 11/24/2022]
Abstract
Human transcriptional adaptor hADA2a is an important component of the general control nonderepressible 5 (GCN5) histone acetyltransferase complex. Here, we report that coiled-coil domain containing 134 (CCDC134), a novel nuclear protein, binds to hADA2a and enhances the stability of the hADA2a protein in unstressed conditions. Furthermore, CCDC134 was found to participate in the p300/CBP-associated factor (PCAF) complex via hADA2a and affect the histone acetyltransferase activity of the complex. We also found that CCDC134 increased the PCAF-dependent K320 acetylation of p53 and p53 protein stability in the presence of hADA2a overexpression. Moreover, we demonstrated the biological significance of the interaction between CCDC134 and hADA2a. CCDC134 showed obvious nuclear accumulation after ultraviolet (UV) irradiation, and the knockdown of endogenous CCDC134 suppressed hADA2a-induced cell apoptosis activity and G1/S cell cycle arrest. Together, our findings indicate that CCDC134 might act as a novel regulator of hADA2a, and plays roles in the PCAF complex via hADA2a to affect its acetyltransferase activity and UV-induced DNA damage repair.
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Affiliation(s)
- Jing Huang
- Peking University Center for Human Disease Genomics, 38 Xueyuan Road, Haidian District 100191, Beijing, People's Republic of China
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48
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Jong JE, Jeong KW, Shin H, Hwang LR, Lee D, Seo T. Human papillomavirus type 16 E6 protein inhibits DNA fragmentation via interaction with DNA fragmentation factor 40. Cancer Lett 2012; 324:109-17. [PMID: 22609799 DOI: 10.1016/j.canlet.2012.05.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2012] [Revised: 05/09/2012] [Accepted: 05/11/2012] [Indexed: 01/06/2023]
Abstract
The E6 oncoprotein of human papillomavirus (HPV) is critical in cervical cancer development. Using the yeast two-hybrid assay, we showed that HPV-16 E6 (16E6) interacts with one of the DNA fragmentation factors (DFFs), DFF40, which mediates DNA degradation during apoptosis. Furthermore, 16E6 interacts with DFF40 through its zinc finger motif 2 and a bridge section linking the two zinc finger motifs. DNA fragmentation assays disclosed that 16E6 binding to DFF40 leads to blockage of DNA cleavage. Our data collectively suggest that suppression of DNA fragmentation through 16E6-DFF40 interaction is a central event promoting tumorigenesis.
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Affiliation(s)
- Jae Eun Jong
- Department of Life Science, Dongguk University-Seoul, Seoul 100-715, Republic of Korea
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49
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Virology and molecular pathogenesis of HPV (human papillomavirus)-associated oropharyngeal squamous cell carcinoma. Biochem J 2012; 443:339-53. [PMID: 22452816 DOI: 10.1042/bj20112017] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The current literature fully supports HPV (human papillomavirus)-associated OPSCC (oropharyngeal squamous cell carcinoma) as a unique clinical entity. It affects an unambiguous patient population with defined risk factors, has a genetic expression pattern more similar to cervical squamous cell carcinoma than non-HPV-associated HNSCC (head and neck squamous cell carcinoma), and may warrant divergent clinical management compared with HNSCC associated with traditional risk factors. However, a detailed understanding of the molecular mechanisms driving these differences and the ability to exploit this knowledge to improve clinical management of OPSCC has not yet come to fruition. The present review summarizes the aetiology of HPV-positive (HPV+) OPSCC and provides a detailed overview of HPV virology and molecular pathogenesis relevant to infection of oropharyngeal tissues. Methods of detection and differential gene expression analyses are also summarized. Future research into mechanisms that mediate tropism of HPV to oropharyngeal tissues, improved detection strategies and the pathophysiological significance of altered gene and microRNA expression profiles is warranted.
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50
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Transactivation activity of human papillomavirus type 16 E6*I on aldo-keto reductase genes enhances chemoresistance in cervical cancer cells. J Gen Virol 2012; 93:1081-1092. [DOI: 10.1099/vir.0.038265-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The oncogenic E6 proteins produced by high-risk human papillomaviruses (HPVs) are invariably expressed in cervical carcinomas and are multifunctional proteins capable of affecting host-cell proliferation by binding and deregulating key host molecules such as p53. High-risk HPVs, including HPV16, have the unique ability to splice the E6 viral transcript, resulting in the production of a truncated E6 protein known as E6*I whose precise biological function is unclear. This study explored the changes in gene expression of the cervical cancer C33A cell line stably expressing HPV16 E6*I (16E6*I) and observed the upregulation of ten genes. Two of these genes were aldo-keto reductases (AKR1Cs), AKR1C1 and AKR1C3, which have been implicated in drug resistance. The results demonstrated that expression of 16E6*I, but not full-length E6, specifically increased AKR1C1 transcript levels although it did not alter AKR1C2 transcript levels. HPV16 E7 alone also had the ability to cause a moderate increase in AKR1C3 at both mRNA and protein levels. Site-directed mutagenesis of 16E6*I revealed that transactivation activity was abolished in R8A, R10A and T17A 16E6*I mutants without altering their intracellular localization patterns. Loss of transactivation activity of the 16E6*I mutants resulted in a significant loss of AKR1C expression and a decrease in drug resistance. Analysis of the AKR1C1 promoter revealed that, unlike the E6 protein, 16E6*I does not mediate transactivation activity solely through Sp1-binding sites. Taken together, it was concluded that 16E6*I has a novel function in upregulating expression of AKR1C and, in concert with E7, has implications for drug treatment in HPV-mediated cervical cancer.
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