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Rahman M, Nguyen TM, Lee GJ, Kim B, Park MK, Lee CH. Unraveling the Role of Ras Homolog Enriched in Brain (Rheb1 and Rheb2): Bridging Neuronal Dynamics and Cancer Pathogenesis through Mechanistic Target of Rapamycin Signaling. Int J Mol Sci 2024; 25:1489. [PMID: 38338768 PMCID: PMC10855792 DOI: 10.3390/ijms25031489] [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: 12/15/2023] [Revised: 01/14/2024] [Accepted: 01/17/2024] [Indexed: 02/12/2024] Open
Abstract
Ras homolog enriched in brain (Rheb1 and Rheb2), small GTPases, play a crucial role in regulating neuronal activity and have gained attention for their implications in cancer development, particularly in breast cancer. This study delves into the intricate connection between the multifaceted functions of Rheb1 in neurons and cancer, with a specific focus on the mTOR pathway. It aims to elucidate Rheb1's involvement in pivotal cellular processes such as proliferation, apoptosis resistance, migration, invasion, metastasis, and inflammatory responses while acknowledging that Rheb2 has not been extensively studied. Despite the recognized associations, a comprehensive understanding of the intricate interplay between Rheb1 and Rheb2 and their roles in both nerve and cancer remains elusive. This review consolidates current knowledge regarding the impact of Rheb1 on cancer hallmarks and explores the potential of Rheb1 as a therapeutic target in cancer treatment. It emphasizes the necessity for a deeper comprehension of the molecular mechanisms underlying Rheb1-mediated oncogenic processes, underscoring the existing gaps in our understanding. Additionally, the review highlights the exploration of Rheb1 inhibitors as a promising avenue for cancer therapy. By shedding light on the complicated roles between Rheb1/Rheb2 and cancer, this study provides valuable insights to the scientific community. These insights are instrumental in guiding the identification of novel targets and advancing the development of effective therapeutic strategies for treating cancer.
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Affiliation(s)
- Mostafizur Rahman
- College of Pharmacy, Dongguk University, Seoul 04620, Republic of Korea; (M.R.); (G.J.L.)
| | - Tuan Minh Nguyen
- College of Pharmacy, Dongguk University, Seoul 04620, Republic of Korea; (M.R.); (G.J.L.)
| | - Gi Jeong Lee
- College of Pharmacy, Dongguk University, Seoul 04620, Republic of Korea; (M.R.); (G.J.L.)
| | - Boram Kim
- College of Pharmacy, Dongguk University, Seoul 04620, Republic of Korea; (M.R.); (G.J.L.)
| | - Mi Kyung Park
- Department of BioHealthcare, Hwasung Medi-Science University, Hwaseong-si 18274, Republic of Korea
| | - Chang Hoon Lee
- College of Pharmacy, Dongguk University, Seoul 04620, Republic of Korea; (M.R.); (G.J.L.)
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2
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Smith AE, Chan S, Wang Z, McCloskey A, Reilly Q, Wang JZ, Patel HV, Koshizuka K, Soifer HS, Kessler L, Dayoub A, Villaflor V, Adkins DR, Bruce JY, Ho AL, Perez CA, Hanna GJ, Gascó Hernández A, Saunders A, Dale S, Gutkind JS, Burrows F, Malik S. Tipifarnib Potentiates the Antitumor Effects of PI3Kα Inhibition in PIK3CA- and HRAS-Dysregulated HNSCC via Convergent Inhibition of mTOR Activity. Cancer Res 2023; 83:3252-3263. [PMID: 37339176 PMCID: PMC10543974 DOI: 10.1158/0008-5472.can-23-0282] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Revised: 05/23/2023] [Accepted: 06/16/2023] [Indexed: 06/22/2023]
Abstract
Outcomes for patients with recurrent/metastatic (R/M) head and neck squamous cell carcinoma (HNSCC) are poor, with median overall survival (OS) ranging from 6 to 18 months. For those who progress on standard-of-care (chemo)immunotherapy, treatment options are limited, necessitating the development of rational therapeutic strategies. Toward this end, we targeted the key HNSCC drivers PI3K-mTOR and HRAS via the combination of tipifarnib, a farnesyltransferase (FTase) inhibitor, and alpelisib, a PI3Kα inhibitor, in multiple molecularly defined subsets of HNSCC. Tipifarnib synergized with alpelisib at the level of mTOR in PI3Kα- or HRAS-dependent HNSCCs, leading to marked cytotoxicity in vitro and tumor regression in vivo. On the basis of these findings, the KURRENT-HN trial was launched to evaluate the effectiveness of this combination in PIK3CA-mutant/amplified and/or HRAS-overexpressing R/M HNSCC. Preliminary evidence supports the clinical activity of this molecular biomarker-driven combination therapy. Combined alpelisib and tipifarnib has potential to benefit >45% of patients with R/M HNSCC. By blocking feedback reactivation of mTORC1, tipifarnib may prevent adaptive resistance to additional targeted therapies, enhancing their clinical utility. SIGNIFICANCE The mechanistically designed, biomarker-matched strategy of combining alpelisib and tipifarnib is efficacious in PIK3CA- and HRAS-dysregulated head and neck squamous carcinoma and could improve outcomes for many patients with recurrent, metastatic disease. See related commentary by Lee et al., p. 3162.
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Affiliation(s)
| | | | - Zhiyong Wang
- Moores Cancer Center, University of California San Diego, La Jolla, California
| | | | | | | | | | - Keiichi Koshizuka
- Moores Cancer Center, University of California San Diego, La Jolla, California
| | | | | | | | | | | | | | - Alan L. Ho
- Memorial Sloan Kettering Cancer Center, New York, New York
| | - Cesar A. Perez
- Sarah Cannon Research Institute at Florida Cancer Specialists, Orlando, Florida
| | | | | | | | | | - J. Silvio Gutkind
- Moores Cancer Center, University of California San Diego, La Jolla, California
- Department of Pharmacology, University of California San Diego, La Jolla, California
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3
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Wang J, Al-Majid D, Brenner JC, Smith JD. Mutant HRas Signaling and Rationale for Use of Farnesyltransferase Inhibitors in Head and Neck Squamous Cell Carcinoma. Target Oncol 2023; 18:643-655. [PMID: 37665491 DOI: 10.1007/s11523-023-00993-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/16/2023] [Indexed: 09/05/2023]
Abstract
Head and neck squamous cell carcinomas (HNSCCs) are often associated with poor outcomes, due at least in part to the limited number of treatment options available for those patients who develop recurrent and/or metastatic disease (R/M HNSCC). Even with the recent validation and approval of immunotherapies in the first-line setting for these patients, the need for the development of new and alternative precision medicine strategies with survival benefit is clear. Oncogenic alterations in the HRAS (Harvey rat sarcoma virus) proto-oncogene are seen in approximately 4-8% of R/M HNSCC tumors. Recently, several preclinical and clinical advancements have been made in the implementation of small-molecule inhibitors that block post-translational farnesylation of HRas, thereby abrogating its downstream oncogenic activity. In this review, we focus on the biology of wild-type and mutant HRas signaling in HNSCC, and rationale for use and outcomes of farnesyltransferase inhibitors in patients with HRAS-mutant tumors.
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Affiliation(s)
- Jiayu Wang
- Department of Pharmacology, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Dana Al-Majid
- Department of Otolaryngology-Head and Neck Surgery, University of Michigan, MSRB III 1150 W. Medical Center Dr., Ann Arbor, MI, 48109, USA
| | - J Chad Brenner
- Department of Pharmacology, University of Michigan, Ann Arbor, MI, 48109, USA.
- Department of Otolaryngology-Head and Neck Surgery, University of Michigan, MSRB III 1150 W. Medical Center Dr., Ann Arbor, MI, 48109, USA.
- Rogel Cancer Center, University of Michigan, Ann Arbor, MI, 48109, USA.
| | - Joshua D Smith
- Department of Otolaryngology-Head and Neck Surgery, University of Michigan, MSRB III 1150 W. Medical Center Dr., Ann Arbor, MI, 48109, USA
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4
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Hartinger R, Lederer EM, Schena E, Lattanzi G, Djabali K. Impact of Combined Baricitinib and FTI Treatment on Adipogenesis in Hutchinson-Gilford Progeria Syndrome and Other Lipodystrophic Laminopathies. Cells 2023; 12:1350. [PMID: 37408186 DOI: 10.3390/cells12101350] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 04/27/2023] [Accepted: 05/04/2023] [Indexed: 07/07/2023] Open
Abstract
Hutchinson-Gilford progeria syndrome (HGPS) is a rare genetic disease that causes premature aging symptoms, such as vascular diseases, lipodystrophy, loss of bone mineral density, and alopecia. HGPS is mostly linked to a heterozygous and de novo mutation in the LMNA gene (c.1824 C > T; p.G608G), resulting in the production of a truncated prelamin A protein called "progerin". Progerin accumulation causes nuclear dysfunction, premature senescence, and apoptosis. Here, we examined the effects of baricitinib (Bar), an FDA-approved JAK/STAT inhibitor, and a combination of Bar and lonafarnib (FTI) treatment on adipogenesis using skin-derived precursors (SKPs). We analyzed the effect of these treatments on the differentiation potential of SKPs isolated from pre-established human primary fibroblast cultures. Compared to mock-treated HGPS SKPs, Bar and Bar + FTI treatments improved the differentiation of HGPS SKPs into adipocytes and lipid droplet formation. Similarly, Bar and Bar + FTI treatments improved the differentiation of SKPs derived from patients with two other lipodystrophic diseases: familial partial lipodystrophy type 2 (FPLD2) and mandibuloacral dysplasia type B (MADB). Overall, the results show that Bar treatment improves adipogenesis and lipid droplet formation in HGPS, FPLD2, and MADB, indicating that Bar + FTI treatment might further ameliorate HGPS pathologies compared to lonafarnib treatment alone.
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Affiliation(s)
- Ramona Hartinger
- Epigenetics of Aging, Department of Dermatology and Allergy, TUM School of Medicine, Munich Institute of Biomedical Engineering (MIBE), Technical University of Munich (TUM), 85748 Garching, Germany
| | - Eva-Maria Lederer
- Epigenetics of Aging, Department of Dermatology and Allergy, TUM School of Medicine, Munich Institute of Biomedical Engineering (MIBE), Technical University of Munich (TUM), 85748 Garching, Germany
| | - Elisa Schena
- Unit of Bologna, CNR Institute of Molecular Genetics "Luigi Luca Cavalli-Sforza", 40136 Bologna, Italy
- IRCCS Istituto Ortopedico Rizzoli, 40136 Bologna, Italy
| | - Giovanna Lattanzi
- Unit of Bologna, CNR Institute of Molecular Genetics "Luigi Luca Cavalli-Sforza", 40136 Bologna, Italy
- IRCCS Istituto Ortopedico Rizzoli, 40136 Bologna, Italy
| | - Karima Djabali
- Epigenetics of Aging, Department of Dermatology and Allergy, TUM School of Medicine, Munich Institute of Biomedical Engineering (MIBE), Technical University of Munich (TUM), 85748 Garching, Germany
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5
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Shams R, Ito Y, Miyatake H. Development of an RHEB-Targeting Peptide To Inhibit mTORC1 Kinase Activity. ACS OMEGA 2022; 7:23479-23486. [PMID: 35847293 PMCID: PMC9280966 DOI: 10.1021/acsomega.2c01865] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
In cancer, the mechanistic/mammalian target of rapamycin complex-1 (mTORC1) is hyperactivated to promote survival under adverse conditions. The kinase activity of mTORC1 is activated by small-GTPase RHEB-GTP. Therefore, a new modality to inhibit mTORC1 activity has emerged, through intercepting RHEB. However, due to the relatively large contact area involved in the interaction between RHEB and mTORC1, facilitating this inhibition through small molecules has been challenging. Here, we report the development of a peptide that can inhibit the RHEB-mTORC1 interaction. The peptide, P1_WT, was designed based on the α-helix (aa 101-115) of the N-heat domain of mTOR to interact with switch II of RHEB. P1_WT bound to RHEB (K D = 0.14 μM) and inhibited RHEB-mTORN-heat interaction (IC50 = 0.33 μM) in vitro. Consequently, P1_WT inhibited mTORC1 activity at a sub-micromolar level (IC50 ∼ 0.3 μM). P1_WT was predicted to be cell-permeable due to the rich content of arginine (23%), enhancing the intracellular translocation. These results show that P1_WT is a potential compound to further develop inhibitors for mTORC1 by intercepting RHEB from mTORC1.
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Affiliation(s)
- Raef Shams
- Emergent
Bioengineering Materials Research Team, RIKEN Center for Emergent Matter Science, Wako, Saitama 351-0198, Japan
- Department
of Life Science, Graduate School of Science and Engineering, Saitama University, Saitama City, Saitama 338-8570, Japan
| | - Yoshihiro Ito
- Emergent
Bioengineering Materials Research Team, RIKEN Center for Emergent Matter Science, Wako, Saitama 351-0198, Japan
- Nano
Medical Engineering Laboratory, RIKEN Cluster
for Pioneering Research, Wako, Saitama 351-0198, Japan
| | - Hideyuki Miyatake
- Department
of Life Science, Graduate School of Science and Engineering, Saitama University, Saitama City, Saitama 338-8570, Japan
- Nano
Medical Engineering Laboratory, RIKEN Cluster
for Pioneering Research, Wako, Saitama 351-0198, Japan
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6
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Javaid S, Schaefer A, Goodwin CM, Nguyen VV, Massey FL, Pierobon M, Gambrell-Sanders D, Waters AM, Lambert KN, Diehl JN, Hobbs GA, Wood KC, Petricoin EF, Der CJ, Cox AD. Concurrent Inhibition of ERK and Farnesyltransferase Suppresses the Growth of HRAS Mutant Head and Neck Squamous Cell Carcinoma. Mol Cancer Ther 2022; 21:762-774. [PMID: 35247914 DOI: 10.1158/1535-7163.mct-21-0142] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2021] [Revised: 08/16/2021] [Accepted: 02/22/2022] [Indexed: 12/24/2022]
Abstract
Human papilloma virus (HPV)-negative head and neck squamous cell carcinoma (HNSCC) is a common cancer worldwide with an unmet need for more effective, less toxic treatments. Currently, both the disease and the treatment of HNSCC cause significant mortality and morbidity. Targeted therapies hold new promise for patients with HPV-negative status whose tumors harbor oncogenic HRAS mutations. Recent promising clinical results have renewed interest in the development of farnesyltransferase inhibitors (FTIs) as a therapeutic strategy for HRAS-mutant cancers. With the advent of clinical evaluation of the FTI tipifarnib for the treatment of HRAS-mutant HNSCC, we investigated the activity of tipifarnib and inhibitors of HRAS effector signaling in HRAS-mutant HNSCC cell lines. First, we validated that HRAS is a cancer driver in HRAS-mutant HNSCC lines. Second, we showed that treatment with the FTI tipifarnib largely phenocopied HRAS silencing, supporting HRAS as a key target of FTI antitumor activity. Third, we performed reverse-phase protein array analyses to profile FTI treatment-induced changes in global signaling, and conducted CRISPR/Cas9 genetic loss-of-function screens to identify previously unreported genes and pathways that modulate sensitivity to tipifarnib. Fourth, we determined that concurrent inhibition of HRAS effector signaling (ERK, PI3K, mTORC1) increased sensitivity to tipifarnib treatment, in part by overcoming tipifarnib-induced compensatory signaling. We also determined that ERK inhibition could block tipifarnib-induced epithelial-to-mesenchymal transition, providing a potential basis for the effectiveness of this combination. Our results support future investigations of these and other combination treatments for HRAS mutant HNSCC.
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Affiliation(s)
- Sehrish Javaid
- Program in Oral and Craniofacial Biomedicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Antje Schaefer
- Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina.,Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Craig M Goodwin
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Victoria V Nguyen
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina.,Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Frances L Massey
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina.,Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Mariaelena Pierobon
- Center for Applied Proteomics and Molecular Medicine, Institute for Advanced Biomedical Research, George Mason University, Manassas, Virginia
| | | | - Andrew M Waters
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Kathryn N Lambert
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - J Nathaniel Diehl
- Curriculum in Genetics & Molecular Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - G Aaron Hobbs
- Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina.,Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Kris C Wood
- Department of Pharmacology and Cancer Biology, Duke University, Durham, North Carolina
| | - Emanuel F Petricoin
- Center for Applied Proteomics and Molecular Medicine, Institute for Advanced Biomedical Research, George Mason University, Manassas, Virginia
| | - Channing J Der
- Program in Oral and Craniofacial Biomedicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina.,Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina.,Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Adrienne D Cox
- Program in Oral and Craniofacial Biomedicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina.,Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina.,Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina.,Department of Radiation Oncology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
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7
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Oleksak P, Nepovimova E, Chrienova Z, Musilek K, Patocka J, Kuca K. Contemporary mTOR inhibitor scaffolds to diseases breakdown: A patent review (2015–2021). Eur J Med Chem 2022; 238:114498. [DOI: 10.1016/j.ejmech.2022.114498] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2022] [Revised: 05/16/2022] [Accepted: 05/26/2022] [Indexed: 02/06/2023]
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8
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Zhong Y, Zhou X, Guan KL, Zhang J. Rheb regulates nuclear mTORC1 activity independent of farnesylation. Cell Chem Biol 2022; 29:1037-1045.e4. [PMID: 35294906 DOI: 10.1016/j.chembiol.2022.02.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Revised: 10/26/2021] [Accepted: 02/10/2022] [Indexed: 11/26/2022]
Abstract
The small GTPase Ras homolog enriched in brain (Rheb) plays a critical role in activating the mechanistic target of rapamycin complex 1 (mTORC1), a signaling hub that regulates various cellular functions. We recently observed nuclear mTORC1 activity, raising an intriguing question as to how Rheb, which is known to be farnesylated and localized to intracellular membranes, regulates nuclear mTORC1. In this study, we found that active Rheb is present in the nucleus and required for nuclear mTORC1 activity. We showed that inhibition of farnesyltransferase reduced cytosolic, but not nuclear, mTORC1 activity. Furthermore, a farnesylation-deficient Rheb mutant, with preferential nuclear localization and specific lysosome tethering, enables nuclear and cytosolic mTORC1 activities, respectively. These data suggest that non-farnesylated Rheb is capable of interacting with and activating mTORC1, providing mechanistic insights into the molecular functioning of Rheb as well as regulation of the recently observed, active pool of nuclear mTORC1.
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Affiliation(s)
- Yanghao Zhong
- Department of Pharmacology, University of California, San Diego, La Jolla, CA, USA; Biomedical Sciences Graduate Program, University of California, San Diego, La Jolla, CA, USA
| | - Xin Zhou
- Department of Pharmacology, University of California, San Diego, La Jolla, CA, USA
| | - Kun-Liang Guan
- Department of Pharmacology, University of California, San Diego, La Jolla, CA, USA; Moores Cancer Center, University of California, San Diego, La Jolla, CA, USA
| | - Jin Zhang
- Department of Pharmacology, University of California, San Diego, La Jolla, CA, USA; Moores Cancer Center, University of California, San Diego, La Jolla, CA, USA; Department of Bioengineering, University of California, San Diego, La Jolla, CA, USA; Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA, USA.
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9
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Yi YW, You KS, Park JS, Lee SG, Seong YS. Ribosomal Protein S6: A Potential Therapeutic Target against Cancer? Int J Mol Sci 2021; 23:ijms23010048. [PMID: 35008473 PMCID: PMC8744729 DOI: 10.3390/ijms23010048] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Revised: 12/19/2021] [Accepted: 12/20/2021] [Indexed: 12/12/2022] Open
Abstract
Ribosomal protein S6 (RPS6) is a component of the 40S small ribosomal subunit and participates in the control of mRNA translation. Additionally, phospho (p)-RPS6 has been recognized as a surrogate marker for the activated PI3K/AKT/mTORC1 pathway, which occurs in many cancer types. However, downstream mechanisms regulated by RPS6 or p-RPS remains elusive, and the therapeutic implication of RPS6 is underappreciated despite an approximately half a century history of research on this protein. In addition, substantial evidence from RPS6 knockdown experiments suggests the potential role of RPS6 in maintaining cancer cell proliferation. This motivates us to investigate the current knowledge of RPS6 functions in cancer. In this review article, we reviewed the current information about the transcriptional regulation, upstream regulators, and extra-ribosomal roles of RPS6, with a focus on its involvement in cancer. We also discussed the therapeutic potential of RPS6 in cancer.
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Affiliation(s)
- Yong Weon Yi
- Department of Biochemistry, College of Medicine, Dankook University, Cheonan 31116, Chungcheongnam-do, Korea; (Y.W.Y.); (K.S.Y.); (J.-S.P.)
- Department of Nanobiomedical Science, Dankook University, Cheonan 31116, Chungcheongnam-do, Korea
| | - Kyu Sic You
- Department of Biochemistry, College of Medicine, Dankook University, Cheonan 31116, Chungcheongnam-do, Korea; (Y.W.Y.); (K.S.Y.); (J.-S.P.)
- Graduate School of Convergence Medical Science, Dankook University, Cheonan 31116, Chungcheongnam-do, Korea
| | - Jeong-Soo Park
- Department of Biochemistry, College of Medicine, Dankook University, Cheonan 31116, Chungcheongnam-do, Korea; (Y.W.Y.); (K.S.Y.); (J.-S.P.)
| | - Seok-Geun Lee
- Graduate School, Kyung Hee University, Seoul 02447, Korea
- Correspondence: (S.-G.L.); (Y.-S.S.); Tel.: +82-2-961-2355 (S.-G.L.); +82-41-550-3875 (Y.-S.S.); Fax: +82-2-961-9623 (S.-G.L.)
| | - Yeon-Sun Seong
- Department of Biochemistry, College of Medicine, Dankook University, Cheonan 31116, Chungcheongnam-do, Korea; (Y.W.Y.); (K.S.Y.); (J.-S.P.)
- Graduate School of Convergence Medical Science, Dankook University, Cheonan 31116, Chungcheongnam-do, Korea
- Correspondence: (S.-G.L.); (Y.-S.S.); Tel.: +82-2-961-2355 (S.-G.L.); +82-41-550-3875 (Y.-S.S.); Fax: +82-2-961-9623 (S.-G.L.)
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10
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Kessler L, Malik S, Leoni M, Burrows F. Potential of Farnesyl Transferase Inhibitors in Combination Regimens in Squamous Cell Carcinomas. Cancers (Basel) 2021; 13:cancers13215310. [PMID: 34771475 PMCID: PMC8582567 DOI: 10.3390/cancers13215310] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Revised: 10/14/2021] [Accepted: 10/19/2021] [Indexed: 11/16/2022] Open
Abstract
Current therapies for recurrent and metastatic SCC are associated with poor outcomes, and options for later lines of treatment are limited. Insights into potential therapeutic targets, as well as mechanisms of resistance to available therapies, have begun to be elucidated, creating the basis for exploration of combination approaches to drive better patient outcomes. Tipifarnib, a farnesyl transferase inhibitor (FTI), is a small molecule drug that has demonstrated encouraging clinical activity in a genetically-defined subset of head and neck squamous cell carcinoma (HNSCC)-specifically, tumors that express a mutation in the HRAS protooncogene. More recently, bioinformatic analyses and results from patient-derived xenograft modeling indicate that HRAS pathway dependency may extend to a broader subpopulation of SCCs beyond HRAS mutants in the context of combination with agents such as cisplatin, cetuximab, or alpelisib. In addition, tipifarnib can also inactivate additional farnesylated proteins implicated in resistance to approved therapies, including immunotherapies, through a variety of distinct mechanisms, suggesting that tipifarnib could serve as an anchor for combination regimens in SCCs and other tumor types.
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11
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Sanvee GM, Hitzfeld L, Bouitbir J, Krähenbühl S. mTORC2 is an important target for simvastatin-associated toxicity in C2C12 cells and mouse skeletal muscle - Roles of Rap1 geranylgeranylation and mitochondrial dysfunction. Biochem Pharmacol 2021; 192:114750. [PMID: 34461118 DOI: 10.1016/j.bcp.2021.114750] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Revised: 08/24/2021] [Accepted: 08/25/2021] [Indexed: 12/25/2022]
Abstract
Statins decrease the serum LDL-cholesterol concentration and reduce the risk for cardiovascular diseases but can cause myopathy, which may be related to mTORC inhibition. In the current study, we investigated which mTORC is inhibited by simvastatin and by which mechanisms. In C2C12 myoblasts and myotubes and mouse gastrocnemius, simvastatin was cytotoxic and inhibited S6rp and Akt Ser473 phosphorylation, indicating inhibition of mTORC1 and mTORC2, respectively. In contrast to simvastatin, the mTORC1 inhibitor rapamycin did not inhibit mTORC2 activity and was not cytotoxic. Like simvastatin, knock-down of Rictor, an essential component of mTORC2, impaired Akt Ser473 and S6rp phosphorylation and was cytotoxic for C2C12 myoblasts, suggesting that mTORC2 inhibition is an important myotoxic mechanism. The investigation of the mechanism of mTORC2 inhibition showed that simvastatin impaired Ras farnesylation, which was prevented by farnesol but without restoring mTORC2 activity. In comparison, Rap1 knock-down reduced mTORC2 activity and was cytotoxic for C2C12 myoblasts. Simvastatin impaired Rap1 geranylgeranylation and function, which was prevented by geranylgeraniol. In addition, simvastatin and the complex III inhibitor antimycin A caused mitochondrial superoxide accumulation and impaired the activity of mTORC2, which could partially be prevented by the antioxidant MitoTEMPO. In conclusion, mTORC2 inhibition is an important mechanism of simvastatin-induced myotoxicity. Simvastatin inhibits mTORC2 by impairing geranylgeranylation of Rap1 and by inducing mitochondrial dysfunction.
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Affiliation(s)
- Gerda M Sanvee
- Division of Clinical Pharmacology & Toxicology, University Hospital, Basel, Switzerland; Department of Biomedicine, University of Basel, Switzerland
| | - Leonie Hitzfeld
- Division of Clinical Pharmacology & Toxicology, University Hospital, Basel, Switzerland
| | - Jamal Bouitbir
- Division of Clinical Pharmacology & Toxicology, University Hospital, Basel, Switzerland; Department of Biomedicine, University of Basel, Switzerland; Division of Molecular and Systemic Toxicology, Department of Pharmaceutical Sciences, University of Basel, Switzerland; Swiss Centre for Applied Human Research (SCAHT), Switzerland
| | - Stephan Krähenbühl
- Division of Clinical Pharmacology & Toxicology, University Hospital, Basel, Switzerland; Department of Biomedicine, University of Basel, Switzerland; Swiss Centre for Applied Human Research (SCAHT), Switzerland.
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12
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Jeong A, Cheng S, Zhong R, Bennett DA, Bergö MO, Li L. Protein farnesylation is upregulated in Alzheimer's human brains and neuron-specific suppression of farnesyltransferase mitigates pathogenic processes in Alzheimer's model mice. Acta Neuropathol Commun 2021; 9:129. [PMID: 34315531 PMCID: PMC8314463 DOI: 10.1186/s40478-021-01231-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Accepted: 07/16/2021] [Indexed: 11/10/2022] Open
Abstract
The pathogenic mechanisms underlying the development of Alzheimer's disease (AD) remain elusive and to date there are no effective prevention or treatment for AD. Farnesyltransferase (FT) catalyzes a key posttranslational modification process called farnesylation, in which the isoprenoid farnesyl pyrophosphate is attached to target proteins, facilitating their membrane localization and their interactions with downstream effectors. Farnesylated proteins, including the Ras superfamily of small GTPases, are involved in regulating diverse physiological and pathological processes. Emerging evidence suggests that isoprenoids and farnesylated proteins may play an important role in the pathogenesis of AD. However, the dynamics of FT and protein farnesylation in human brains and the specific role of neuronal FT in the pathogenic progression of AD are not known. Here, using postmortem brain tissue from individuals with no cognitive impairment (NCI), mild cognitive impairment (MCI), or Alzheimer's dementia, we found that the levels of FT and membrane-associated H-Ras, an exclusively farnesylated protein, and its downstream effector ERK were markedly increased in AD and MCI compared with NCI. To elucidate the specific role of neuronal FT in AD pathogenesis, we generated the transgenic AD model APP/PS1 mice with forebrain neuron-specific FT knockout, followed by a battery of behavioral assessments, biochemical assays, and unbiased transcriptomic analysis. Our results showed that the neuronal FT deletion mitigates memory impairment and amyloid neuropathology in APP/PS1 mice through suppressing amyloid generation and reversing the pathogenic hyperactivation of mTORC1 signaling. These findings suggest that aberrant upregulation of protein farnesylation is an early driving force in the pathogenic cascade of AD and that targeting FT or its downstream signaling pathways presents a viable therapeutic strategy against AD.
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13
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Egawa N, Tanaka T, Matsufuji S, Yamada K, Ito K, Kitagawa H, Okuyama K, Kitajima Y, Noshiro H. Antitumor effects of low-dose tipifarnib on the mTOR signaling pathway and reactive oxygen species production in HIF-1α-expressing gastric cancer cells. FEBS Open Bio 2021; 11:1465-1475. [PMID: 33773069 PMCID: PMC8091580 DOI: 10.1002/2211-5463.13154] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Revised: 02/15/2021] [Accepted: 03/24/2021] [Indexed: 12/24/2022] Open
Abstract
Farnesyltransferase inhibitors (FTIs) suppress tumor aggressiveness in several malignancies by inhibiting Ras signaling. However, treatment of cells with a low dose of the FTI tipifarnib suppresses the expression of hypoxia‐inducible factor‐1α (HIF‐1α) and results in antitumor effects without inhibiting the Ras pathway. Although we previously reported that elevated HIF‐1α expression is associated with an aggressive phenotype in gastric cancer (GC), little is known about the antitumor effects of FTIs on GC. In this study, we examined the relationship between the antitumor effects of low‐dose tipifarnib and HIF‐1α expression in GC cells. Under normoxic conditions, HIF‐1α was expressed only in MKN45 and KATOIII cells. The inhibitory effect of tipifarnib on HIF‐1α was observed in HIF‐1α‐positive cells. Low‐dose tipifarnib had antitumor effects only on HIF‐1α‐positive cells both in vitro and in vivo. Furthermore, low‐dose tipifarnib inactivated ras homolog enriched in brain (Rheb)/mammalian target of rapamycin (mTOR) signaling and decreased intracellular reactive oxygen species (ROS) levels in HIF‐1α‐positive GC cells. Our results that the antitumor effects of low‐dose tipifarnib are at least partially mediated through suppression of mTOR signaling and HIF‐1α expression via inhibition of Rheb farnesylation and reduction in ROS levels. These findings suggest that low‐dose tipifarnib may be capable of exerting an antitumor effect that is dependent on HIF‐1α expression in GC cells. Tipifarnib may have potential as a novel therapeutic agent for HIF‐1α‐expressing GC exhibiting an aggressive phenotype.
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Affiliation(s)
- Noriyuki Egawa
- Department of Surgery, Saga University Faculty of Medicine, Japan
| | - Tomokazu Tanaka
- Department of Surgery, Saga University Faculty of Medicine, Japan
| | - Shohei Matsufuji
- Department of Surgery, Saga University Faculty of Medicine, Japan
| | - Kohei Yamada
- Department of Surgery, Saga University Faculty of Medicine, Japan
| | - Kotaro Ito
- Department of Surgery, Saga University Faculty of Medicine, Japan
| | - Hiroshi Kitagawa
- Department of Surgery, Saga University Faculty of Medicine, Japan
| | | | - Yoshihiko Kitajima
- Department of Surgery, Saga University Faculty of Medicine, Japan.,Department of Surgery, National Hospital Organization Higashisaga Hospital, Saga, Japan
| | - Hirokazu Noshiro
- Department of Surgery, Saga University Faculty of Medicine, Japan
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14
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Sato T, Mukai S, Ikeda H, Mishiro-Sato E, Akao K, Kobayashi T, Hino O, Shimono W, Shibagaki Y, Hattori S, Sekido Y. Silencing of SmgGDS, a Novel mTORC1 Inducer That Binds to RHEBs, Inhibits Malignant Mesothelioma Cell Proliferation. Mol Cancer Res 2021; 19:921-931. [PMID: 33574130 DOI: 10.1158/1541-7786.mcr-20-0637] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2020] [Revised: 12/15/2020] [Accepted: 02/04/2021] [Indexed: 11/16/2022]
Abstract
Malignant mesothelioma (MM) is an aggressive tumor that typically develops after a long latency following asbestos exposure. Although mechanistic target of rapamycin complex 1 (mTORC1) activation enhances MM cell growth, the mTORC1 inhibitor everolimus has shown limited efficacy in clinical trials of MM patients. We explored the mechanism underlying mTORC1 activation in MM cells and its effects on cell proliferation and progression. Analysis of the expression profiles of 87 MMs from The Cancer Genome Atlas revealed that 40 samples (46%) displayed altered expression of RPTOR (mTORC1 component) and genes immediately upstream that activate mTORC1. Among them, we focused on RHEB and RHEBL1, which encode direct activators of mTORC1. Exogenous RHEBL1 expression enhanced MM cell growth, indicating that RHEB-mTORC1 signaling acts as a pro-oncogenic cascade. We investigated molecules that directly activate RHEBs, identifying SmgGDS as a novel RHEB-binding protein. SmgGDS knockdown reduced mTORC1 activation and inhibited the proliferation of MM cells with mTORC1 activation. Interestingly, SmgGDS displayed high binding affinity with inactive GDP-bound RHEBL1, and its knockdown reduced cytosolic RHEBL1 without affecting its activation. These findings suggest that SmgGDS retains GDP-bound RHEBs in the cytosol, whereas GTP-bound RHEBs are localized on intracellular membranes to promote mTORC1 activation. We revealed a novel role for SmgGDS in the RHEB-mTORC1 pathway and its potential as a therapeutic target in MM with aberrant mTORC1 activation. IMPLICATIONS: Our data showing that SmgGDS regulates RHEB localization to activate mTORC1 indicate that SmgGDS can be used as a new therapeutic target for MM exhibiting mTORC1 activation.
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Affiliation(s)
- Tatsuhiro Sato
- Division of Cancer Biology, Aichi Cancer Center Research Institute, Nagoya, Aichi, Japan
| | - Satomi Mukai
- Division of Cancer Biology, Aichi Cancer Center Research Institute, Nagoya, Aichi, Japan
| | - Haruna Ikeda
- Division of Cancer Biology, Aichi Cancer Center Research Institute, Nagoya, Aichi, Japan
| | - Emi Mishiro-Sato
- Division of Pathophysiology, Aichi Cancer Center Research Institute, Nagoya, Aichi, Japan
| | - Ken Akao
- Division of Cancer Biology, Aichi Cancer Center Research Institute, Nagoya, Aichi, Japan.,Department of Respiratory Medicine, Fujita Health University School of Medicine, Toyoake, Aichi, Japan
| | - Toshiyuki Kobayashi
- Department of Molecular Pathogenesis, Graduate School of Medicine, Juntendo University, Bunkyo-ku, Tokyo, Japan
| | - Okio Hino
- Department of Molecular Pathogenesis, Graduate School of Medicine, Juntendo University, Bunkyo-ku, Tokyo, Japan
| | - Wataru Shimono
- Division of Biochemistry, School of Pharmaceutical Sciences, Kitasato University, Minato-ku, Tokyo, Japan
| | - Yoshio Shibagaki
- Division of Biochemistry, School of Pharmaceutical Sciences, Kitasato University, Minato-ku, Tokyo, Japan
| | - Seisuke Hattori
- Division of Biochemistry, School of Pharmaceutical Sciences, Kitasato University, Minato-ku, Tokyo, Japan
| | - Yoshitaka Sekido
- Division of Cancer Biology, Aichi Cancer Center Research Institute, Nagoya, Aichi, Japan. .,Division of Molecular and Cellular Oncology, Nagoya University Graduate School of Medicine, Nagoya, Aichi, Japan
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15
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Key Enzymes for the Mevalonate Pathway in the Cardiovascular System. J Cardiovasc Pharmacol 2021; 77:142-152. [PMID: 33538531 DOI: 10.1097/fjc.0000000000000952] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Accepted: 10/15/2020] [Indexed: 11/25/2022]
Abstract
ABSTRACT Isoprenylation is an important post-transcriptional modification of small GTPases required for their activation and function. Isoprenoids, including farnesyl pyrophosphate (FPP) and geranylgeranyl pyrophosphate, are indispensable for isoprenylation by serving as donors of a prenyl moiety to small G proteins. In the human body, isoprenoids are mainly generated by the mevalonate pathway (also known as the cholesterol-synthesis pathway). The hydroxymethylglutaryl coenzyme A reductase catalyzes the first rate-limiting steps of the mevalonate pathway, and its inhibitor (statins) are widely used as lipid-lowering agents. In addition, the FPP synthase is also of critical importance for the regulation of the isoprenoids production, for which the inhibitor is mainly used in the treatment of osteoporosis. Synthetic FPP can be further used to generate geranylgeranyl pyrophosphate and cholesterol. Recent studies suggest a role for isoprenoids in the genesis and development of cardiovascular disorders, such as pathological cardiac hypertrophy, fibrosis, endothelial dysfunction, and fibrotic responses of smooth-muscle cells. Furthermore, statins and FPP synthase inhibitors have also been applied for the management of heart failure and other cardiovascular diseases rather than their clinical use for hyperlipidemia or bone diseases. In this review, we focus on the function of several critical enzymes, including hydroxymethylglutaryl coenzyme A reductase, FPP synthase, farnesyltransferase, and geranylgeranyltransferase in the mevalonate pathway which are involved in regulating the generation of isoprenoids and isoprenylation of small GTPases, and their pathophysiological role in the cardiovascular system. Moreover, we summarize recent research into applications of statins and the FPP synthase inhibitors to treat cardiovascular diseases, rather than for their traditional indications respectively.
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16
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Nesterov SV, Yaguzhinsky LS, Podoprigora GI, Nartsissov YR. Amino Acids as Regulators of Cell Metabolism. BIOCHEMISTRY (MOSCOW) 2021; 85:393-408. [PMID: 32569548 DOI: 10.1134/s000629792004001x] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
In this review, we discuss the principles of regulation and synchronization of metabolic processes in mammalian cells using a two-component model of cell metabolism consisting of a controlling signaling system that regulates major enzymatic cascades and executive metabolic system that directly performs biosynthetic reactions. This approach has allowed us to distinguish two transitional metabolic states (from catabolism to anabolism and vice versa) accompanied by major rearrangements in the signaling system. The signaling system of natural amino acids was selected, because amino acids are involved in both signaling and executive metabolic subsystems of general cell metabolism. We have developed a graphical representation of metabolic events that allowed us to demonstrate the succession of processes occurring in both metabolic subsystems during complete metabolic cycle in a non-dividing cell. An important revealed feature of the amino acid signaling system is that the signaling properties of amino acid are determined not only by their molecular structure, but also by the location within the cell. Four major signaling groups of amino acids have been identified that localize to lysosomes, mitochondria, cytosol, and extracellular space adjacent to the plasma membrane. Although these amino acids groups are similar in the composition, they have different receptors. We also proposed a scheme for the metabolism regulation by amino acids signaling that can serve as a basis for developing more complete spatio-temporal picture of metabolic regulation involving a wide variety of intracellular signaling cascades.
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Affiliation(s)
- S V Nesterov
- Institute of Cytochemistry and Molecular Pharmacology, Moscow, 115404, Russia.,Moscow Institute of Physics and Technology, Dolgoprudny, Moscow Region, 141701, Russia
| | - L S Yaguzhinsky
- Institute of Cytochemistry and Molecular Pharmacology, Moscow, 115404, Russia. .,Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119991, Russia
| | - G I Podoprigora
- Institute of Cytochemistry and Molecular Pharmacology, Moscow, 115404, Russia
| | - Ya R Nartsissov
- Institute of Cytochemistry and Molecular Pharmacology, Moscow, 115404, Russia
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17
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Carabott M, Case R, Dhakal S, Macreadie I. Lipids, statins and susceptibility to SARS-CoV-2 and influenza A viruses. MICROBIOLOGY AUSTRALIA 2021. [DOI: 10.1071/ma21021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The extensive and on-going epidemiology studies of the SARS-CoV-2 pandemic have raised interesting observations on statins reducing COVID-19 severity. In this review, literature is analysed to examine how statins affect COVID-19 and influenza A, another pandemic respiratory virus. This information could be useful to prevent or reduce disease severity caused by respiratory viruses.
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18
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CRISPR/Cas9 genome-wide loss-of-function screening identifies druggable cellular factors involved in sunitinib resistance in renal cell carcinoma. Br J Cancer 2020; 123:1749-1756. [PMID: 32968206 PMCID: PMC7723036 DOI: 10.1038/s41416-020-01087-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Revised: 08/17/2020] [Accepted: 09/03/2020] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Multi-targeted tyrosine kinase inhibitors (TKIs) are the standard of care for patients with advanced clear cell renal cell carcinoma (ccRCC). However, a significant number of ccRCC patients are primarily refractory to targeted therapeutics, showing neither disease stabilisation nor clinical benefits. METHODS We used CRISPR/Cas9-based high-throughput loss of function (LOF) screening to identify cellular factors involved in the resistance to sunitinib. Next, we validated druggable molecular factors that are synthetically lethal with sunitinib treatment using cell and animal models of ccRCC. RESULTS Our screening identified farnesyltransferase among the top hits contributing to sunitinib resistance in ccRCC. Combined treatment with farnesyltransferase inhibitor lonafarnib potently augmented the anti-tumour efficacy of sunitinib both in vitro and in vivo. CONCLUSION CRISPR/Cas9 LOF screening presents a promising approach to identify and target cellular factors involved in the resistance to anti-cancer therapeutics.
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19
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Natarajan N, Thiruvenkatam V. An Insight of Scientific Developments in TSC for Better Therapeutic Strategy. Curr Top Med Chem 2020; 20:2080-2093. [PMID: 32842942 DOI: 10.2174/1568026620666200825170355] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 06/15/2020] [Accepted: 07/20/2020] [Indexed: 11/22/2022]
Abstract
Tuberous sclerosis complex (TSC) is a rare genetic disease, which is characterized by noncancerous tumors in multi-organ systems in the body. Mutations in the TSC1 or TSC2 genes are known to cause the disease. The resultant mutant proteins TSC1 (hamartin) and TSC2 (tuberin) complex evade its normal tumor suppressor function, which leads to abnormal cell growth and proliferation. Both TSC1 and TSC2 are involved in several protein-protein interactions, which play a significant role in maintaining cellular homeostasis. The recent biochemical, genetic, structural biology, clinical and drug discovery advancements on TSC give a useful insight into the disease as well as the molecular aspects of TSC1 and TSC2. The complex nature of TSC disease, a wide range of manifestations, mosaicism and several other factors limits the treatment choices. This review is a compilation of the course of TSC, starting from its discovery to the current findings that would take us a step ahead in finding a cure for TSC.
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Affiliation(s)
- Nalini Natarajan
- Discipline of Biological Engineering, Indian Institute of Technology Gandhinagar, Gujarat-382355, India
| | - Vijay Thiruvenkatam
- Discipline of Biological Engineering, Indian Institute of Technology Gandhinagar, Gujarat-382355, India
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20
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Escamilla-Ramírez A, Castillo-Rodríguez RA, Zavala-Vega S, Jimenez-Farfan D, Anaya-Rubio I, Briseño E, Palencia G, Guevara P, Cruz-Salgado A, Sotelo J, Trejo-Solís C. Autophagy as a Potential Therapy for Malignant Glioma. Pharmaceuticals (Basel) 2020; 13:ph13070156. [PMID: 32707662 PMCID: PMC7407942 DOI: 10.3390/ph13070156] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 07/01/2020] [Accepted: 07/14/2020] [Indexed: 02/06/2023] Open
Abstract
Glioma is the most frequent and aggressive type of brain neoplasm, being anaplastic astrocytoma (AA) and glioblastoma multiforme (GBM), its most malignant forms. The survival rate in patients with these neoplasms is 15 months after diagnosis, despite a diversity of treatments, including surgery, radiation, chemotherapy, and immunotherapy. The resistance of GBM to various therapies is due to a highly mutated genome; these genetic changes induce a de-regulation of several signaling pathways and result in higher cell proliferation rates, angiogenesis, invasion, and a marked resistance to apoptosis; this latter trait is a hallmark of highly invasive tumor cells, such as glioma cells. Due to a defective apoptosis in gliomas, induced autophagic death can be an alternative to remove tumor cells. Paradoxically, however, autophagy in cancer can promote either a cell death or survival. Modulating the autophagic pathway as a death mechanism for cancer cells has prompted the use of both inhibitors and autophagy inducers. The autophagic process, either as a cancer suppressing or inducing mechanism in high-grade gliomas is discussed in this review, along with therapeutic approaches to inhibit or induce autophagy in pre-clinical and clinical studies, aiming to increase the efficiency of conventional treatments to remove glioma neoplastic cells.
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Affiliation(s)
- Angel Escamilla-Ramírez
- Departamento de Neuroinmunología, Instituto Nacional de Neurología y Neurocirugía, Ciudad de México 14269, Mexico; (A.E.-R.); (I.A.-R.); (G.P.); (P.G.); (A.C.-S.); (J.S.)
| | - Rosa A. Castillo-Rodríguez
- Laboratorio de Oncología Experimental, CONACYT-Instituto Nacional de Pediatría, Ciudad de México 04530, Mexico;
| | - Sergio Zavala-Vega
- Departamento de Patología, Instituto Nacional de Neurología y Neurocirugía, Ciudad de México 14269, Mexico;
| | - Dolores Jimenez-Farfan
- Laboratorio de Inmunología, División de Estudios de Posgrado e Investigación, Facultad de Odontología, Universidad Nacional Autónoma de México, Ciudad de México 04510, Mexico;
| | - Isabel Anaya-Rubio
- Departamento de Neuroinmunología, Instituto Nacional de Neurología y Neurocirugía, Ciudad de México 14269, Mexico; (A.E.-R.); (I.A.-R.); (G.P.); (P.G.); (A.C.-S.); (J.S.)
| | - Eduardo Briseño
- Clínica de Neurooncología, Instituto Nacional de Neurología y Neurocirugía, Ciudad de México 14269, Mexico;
| | - Guadalupe Palencia
- Departamento de Neuroinmunología, Instituto Nacional de Neurología y Neurocirugía, Ciudad de México 14269, Mexico; (A.E.-R.); (I.A.-R.); (G.P.); (P.G.); (A.C.-S.); (J.S.)
| | - Patricia Guevara
- Departamento de Neuroinmunología, Instituto Nacional de Neurología y Neurocirugía, Ciudad de México 14269, Mexico; (A.E.-R.); (I.A.-R.); (G.P.); (P.G.); (A.C.-S.); (J.S.)
| | - Arturo Cruz-Salgado
- Departamento de Neuroinmunología, Instituto Nacional de Neurología y Neurocirugía, Ciudad de México 14269, Mexico; (A.E.-R.); (I.A.-R.); (G.P.); (P.G.); (A.C.-S.); (J.S.)
| | - Julio Sotelo
- Departamento de Neuroinmunología, Instituto Nacional de Neurología y Neurocirugía, Ciudad de México 14269, Mexico; (A.E.-R.); (I.A.-R.); (G.P.); (P.G.); (A.C.-S.); (J.S.)
| | - Cristina Trejo-Solís
- Departamento de Neuroinmunología, Instituto Nacional de Neurología y Neurocirugía, Ciudad de México 14269, Mexico; (A.E.-R.); (I.A.-R.); (G.P.); (P.G.); (A.C.-S.); (J.S.)
- Correspondence: ; Tel.: +52-555-060-4040
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21
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Han S, Jeong YY, Sheshadri P, Su X, Cai Q. Mitophagy regulates integrity of mitochondria at synapses and is critical for synaptic maintenance. EMBO Rep 2020; 21:e49801. [PMID: 32627320 DOI: 10.15252/embr.201949801] [Citation(s) in RCA: 54] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Revised: 06/01/2020] [Accepted: 06/05/2020] [Indexed: 01/25/2023] Open
Abstract
Synaptic mitochondria are particularly vulnerable to physiological insults, and defects in synaptic mitochondria are linked to early pathophysiology of Alzheimer's disease (AD). Mitophagy, a cargo-specific autophagy for elimination of dysfunctional mitochondria, constitutes a key quality control mechanism. However, how mitophagy ensures synaptic mitochondrial integrity remains largely unknown. Here, we reveal Rheb and Snapin as key players regulating mitochondrial homeostasis at synapses. Rheb initiates mitophagy to target damaged mitochondria for autophagy, whereas dynein-Snapin-mediated retrograde transport promotes clearance of mitophagosomes from synaptic terminals. We demonstrate that synaptic accumulation of mitophagosomes is a feature in AD-related mutant hAPP mouse brains, which is attributed to increased mitophagy initiation coupled with impaired removal of mitophagosomes from AD synapses due to defective retrograde transport. Furthermore, while deficiency in dynein-Snapin-mediated retrograde transport recapitulates synaptic mitophagy stress and induces synaptic degeneration, elevated Snapin expression attenuates mitochondrial defects and ameliorates synapse loss in AD mouse brains. Taken together, our study provides new insights into mitophagy regulation of synaptic mitochondrial integrity, establishing a foundation for mitigating AD-associated mitochondria deficits and synaptic damage through mitophagy enhancement.
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Affiliation(s)
- Sinsuk Han
- Division of Life Science, Department of Cell Biology and Neuroscience, School of Arts and Sciences, Rutgers, The State University of New Jersey, Piscataway, NJ, USA
| | - Yu Young Jeong
- Division of Life Science, Department of Cell Biology and Neuroscience, School of Arts and Sciences, Rutgers, The State University of New Jersey, Piscataway, NJ, USA
| | - Preethi Sheshadri
- Division of Life Science, Department of Cell Biology and Neuroscience, School of Arts and Sciences, Rutgers, The State University of New Jersey, Piscataway, NJ, USA
| | - Xiao Su
- Division of Life Science, Department of Cell Biology and Neuroscience, School of Arts and Sciences, Rutgers, The State University of New Jersey, Piscataway, NJ, USA
| | - Qian Cai
- Division of Life Science, Department of Cell Biology and Neuroscience, School of Arts and Sciences, Rutgers, The State University of New Jersey, Piscataway, NJ, USA
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22
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Blackwood EA, Hofmann C, Santo Domingo M, Bilal AS, Sarakki A, Stauffer W, Arrieta A, Thuerauf DJ, Kolkhorst FW, Müller OJ, Jakobi T, Dieterich C, Katus HA, Doroudgar S, Glembotski CC. ATF6 Regulates Cardiac Hypertrophy by Transcriptional Induction of the mTORC1 Activator, Rheb. Circ Res 2019; 124:79-93. [PMID: 30582446 DOI: 10.1161/circresaha.118.313854] [Citation(s) in RCA: 62] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
RATIONALE Endoplasmic reticulum (ER) stress dysregulates ER proteostasis, which activates the transcription factor, ATF6 (activating transcription factor 6α), an inducer of genes that enhance protein folding and restore ER proteostasis. Because of increased protein synthesis, it is possible that protein folding and ER proteostasis are challenged during cardiac myocyte growth. However, it is not known whether ATF6 is activated, and if so, what its function is during hypertrophic growth of cardiac myocytes. OBJECTIVE To examine the activity and function of ATF6 during cardiac hypertrophy. METHODS AND RESULTS We found that ER stress and ATF6 were activated and ATF6 target genes were induced in mice subjected to an acute model of transverse aortic constriction, or to free-wheel exercise, both of which promote adaptive cardiac myocyte hypertrophy with preserved cardiac function. Cardiac myocyte-specific deletion of Atf6 (ATF6 cKO [conditional knockout]) blunted transverse aortic constriction and exercise-induced cardiac myocyte hypertrophy and impaired cardiac function, demonstrating a role for ATF6 in compensatory myocyte growth. Transcript profiling and chromatin immunoprecipitation identified RHEB (Ras homologue enriched in brain) as an ATF6 target gene in the heart. RHEB is an activator of mTORC1 (mammalian/mechanistic target of rapamycin complex 1), a major inducer of protein synthesis and subsequent cell growth. Both transverse aortic constriction and exercise upregulated RHEB, activated mTORC1, and induced cardiac hypertrophy in wild type mouse hearts but not in ATF6 cKO hearts. Mechanistically, knockdown of ATF6 in neonatal rat ventricular myocytes blocked phenylephrine- and IGF1 (insulin-like growth factor 1)-mediated RHEB induction, mTORC1 activation, and myocyte growth, all of which were restored by ectopic RHEB expression. Moreover, adeno-associated virus 9- RHEB restored cardiac growth to ATF6 cKO mice subjected to transverse aortic constriction. Finally, ATF6 induced RHEB in response to growth factors, but not in response to other activators of ATF6 that do not induce growth, indicating that ATF6 target gene induction is stress specific. CONCLUSIONS Compensatory cardiac hypertrophy activates ER stress and ATF6, which induces RHEB and activates mTORC1. Thus, ATF6 is a previously unrecognized link between growth stimuli and mTORC1-mediated cardiac growth.
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Affiliation(s)
- Erik A Blackwood
- From the Department of Biology, San Diego State University Heart Institute, San Diego State University, CA (E.A.B., C.H., M.S.D., A.S.B., A.S., W.S., A.A., D.J.T., F.W.K., C.C.G.)
| | - Christoph Hofmann
- From the Department of Biology, San Diego State University Heart Institute, San Diego State University, CA (E.A.B., C.H., M.S.D., A.S.B., A.S., W.S., A.A., D.J.T., F.W.K., C.C.G.).,Department of Cardiology, Angiology, and Pneumology, University Hospital Heidelberg, Germany (C.H., O.J.M., H.A.K., S.D.).,German Centre for Cardiovascular Research, Partner Site Heidelberg (C.H., O.J.M., T.J., C.D., H.A.K., S.D.)
| | - Michelle Santo Domingo
- From the Department of Biology, San Diego State University Heart Institute, San Diego State University, CA (E.A.B., C.H., M.S.D., A.S.B., A.S., W.S., A.A., D.J.T., F.W.K., C.C.G.)
| | - Alina S Bilal
- From the Department of Biology, San Diego State University Heart Institute, San Diego State University, CA (E.A.B., C.H., M.S.D., A.S.B., A.S., W.S., A.A., D.J.T., F.W.K., C.C.G.)
| | - Anup Sarakki
- From the Department of Biology, San Diego State University Heart Institute, San Diego State University, CA (E.A.B., C.H., M.S.D., A.S.B., A.S., W.S., A.A., D.J.T., F.W.K., C.C.G.)
| | - Winston Stauffer
- From the Department of Biology, San Diego State University Heart Institute, San Diego State University, CA (E.A.B., C.H., M.S.D., A.S.B., A.S., W.S., A.A., D.J.T., F.W.K., C.C.G.)
| | - Adrian Arrieta
- From the Department of Biology, San Diego State University Heart Institute, San Diego State University, CA (E.A.B., C.H., M.S.D., A.S.B., A.S., W.S., A.A., D.J.T., F.W.K., C.C.G.)
| | - Donna J Thuerauf
- From the Department of Biology, San Diego State University Heart Institute, San Diego State University, CA (E.A.B., C.H., M.S.D., A.S.B., A.S., W.S., A.A., D.J.T., F.W.K., C.C.G.)
| | - Fred W Kolkhorst
- From the Department of Biology, San Diego State University Heart Institute, San Diego State University, CA (E.A.B., C.H., M.S.D., A.S.B., A.S., W.S., A.A., D.J.T., F.W.K., C.C.G.)
| | - Oliver J Müller
- Department of Cardiology, Angiology, and Pneumology, University Hospital Heidelberg, Germany (C.H., O.J.M., H.A.K., S.D.).,German Centre for Cardiovascular Research, Partner Site Heidelberg (C.H., O.J.M., T.J., C.D., H.A.K., S.D.).,Department of Internal Medicine III, University of Kiel, Germany, and German Centre for Cardiovascular Research, Partner Site Hamburg/Kiel/Lübeck, Germany (O.J.M.)
| | - Tobias Jakobi
- Department of Cardiology, Angiology, and Pneumology, University Hospital Heidelberg, Germany (C.H., O.J.M., H.A.K., S.D.).,German Centre for Cardiovascular Research, Partner Site Heidelberg (C.H., O.J.M., T.J., C.D., H.A.K., S.D.).,Section of Bioinformatics and Systems Cardiology, Department of Internal Medicine III, University Hospital Heidelberg, Germany (T.J., C.D.)
| | - Christoph Dieterich
- Department of Cardiology, Angiology, and Pneumology, University Hospital Heidelberg, Germany (C.H., O.J.M., H.A.K., S.D.).,German Centre for Cardiovascular Research, Partner Site Heidelberg (C.H., O.J.M., T.J., C.D., H.A.K., S.D.).,Section of Bioinformatics and Systems Cardiology, Department of Internal Medicine III, University Hospital Heidelberg, Germany (T.J., C.D.)
| | - Hugo A Katus
- Department of Cardiology, Angiology, and Pneumology, University Hospital Heidelberg, Germany (C.H., O.J.M., H.A.K., S.D.).,German Centre for Cardiovascular Research, Partner Site Heidelberg (C.H., O.J.M., T.J., C.D., H.A.K., S.D.)
| | - Shirin Doroudgar
- Department of Cardiology, Angiology, and Pneumology, University Hospital Heidelberg, Germany (C.H., O.J.M., H.A.K., S.D.).,German Centre for Cardiovascular Research, Partner Site Heidelberg (C.H., O.J.M., T.J., C.D., H.A.K., S.D.)
| | - Christopher C Glembotski
- From the Department of Biology, San Diego State University Heart Institute, San Diego State University, CA (E.A.B., C.H., M.S.D., A.S.B., A.S., W.S., A.A., D.J.T., F.W.K., C.C.G.)
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23
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Child DD, Lee JH, Pascua CJ, Chen YH, Mas Monteys A, Davidson BL. Cardiac mTORC1 Dysregulation Impacts Stress Adaptation and Survival in Huntington's Disease. Cell Rep 2019; 23:1020-1033. [PMID: 29694882 PMCID: PMC5967646 DOI: 10.1016/j.celrep.2018.03.117] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Revised: 01/05/2018] [Accepted: 03/26/2018] [Indexed: 12/27/2022] Open
Abstract
Huntington’s disease (HD) is a dominantly inherited neurological disorder caused by CAG-repeat expansion in exon 1 of Huntingtin (HTT). But in addition to the neurological disease, mutant HTT (mHTT), which is ubiquitously expressed, impairs other organ systems. Indeed, epidemiological and animal model studies suggest higher incidence of and mortality from heart disease in HD. Here, we show that the protein complex mTORC1 is dysregulated in two HD mouse models through a mechanism that requires intrinsic mHTT expression. Moreover, restoring cardiac mTORC1 activity with constitutively active Rheb prevents mortality and relieves the mHTT-induced block to hypertrophic adaptation to cardiac stress. Finally, we show that chronic mTORC1 dysregulation is due in part to mislocalization of endogenous Rheb. These data provide insight into the increased cardiac-related mortality of HD patients, with cardiac mHTT expression inhibiting mTORC1 activity, limiting heart growth, and decreasing the heart’s ability to compensate to chronic stress.
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Affiliation(s)
- Daniel D Child
- The Raymond G. Perelman Center for Cellular and Molecular Therapeutics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA; The Perelman School of Medicine, The University of Pennsylvania, Philadelphia, PA, USA
| | - John H Lee
- Department of Psychiatry and Biobehavioral Sciences, University of California Los Angeles, Los Angeles, CA, USA
| | - Christine J Pascua
- Division of Cardiology, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Yong Hong Chen
- The Raymond G. Perelman Center for Cellular and Molecular Therapeutics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Alejandro Mas Monteys
- The Raymond G. Perelman Center for Cellular and Molecular Therapeutics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Beverly L Davidson
- The Raymond G. Perelman Center for Cellular and Molecular Therapeutics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA; The Perelman School of Medicine, The University of Pennsylvania, Philadelphia, PA, USA.
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24
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Klochkov SG, Neganova ME, Yarla NS, Parvathaneni M, Sharma B, Tarasov VV, Barreto G, Bachurin SO, Ashraf GM, Aliev G. Implications of farnesyltransferase and its inhibitors as a promising strategy for cancer therapy. Semin Cancer Biol 2019; 56:128-134. [DOI: 10.1016/j.semcancer.2017.10.010] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Revised: 10/14/2017] [Accepted: 10/30/2017] [Indexed: 12/20/2022]
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25
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Pesquet A, Marzag H, Knorr M, Strohmann C, Lawson AM, Ghinet A, Dubois J, Amaury F, Daïch A, Othman M. Access to 3-spiroindolizines containing an isoindole ring through intra-molecular arylation of spiro-N-acyliminium species: a new family of potent farnesyltransferase inhibitors. Org Biomol Chem 2019; 17:2798-2808. [PMID: 30793727 DOI: 10.1039/c8ob02612b] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Based on N-acyliminium species, two efficient and rapid approaches to diversify spirocyclic systems connected by two different carbon centers to the isoindole ring have been developed. The imide reduction and the tandem oxidative cleavage of olefin/formyl-amide equilibration were at first selected as the key steps for these strategies. Ultimately the intramolecular α-amidoalkylation reaction was achieved through the arylation of α-acetoxy lactams or α-hydroxy lactams using, respectively, a Lewis acid or a Brønsted acid depending on the nature of N-acyliminium precursors. The latter led, in addition to the spiro-6-membered aza-heterocycles, to the formation of scarce spiro-5-membered analogues which show promising inhibitory activities on human farnesyltransferase in the nanomolar range demonstrating improved IC50 values of up to 1.5 nM.
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Affiliation(s)
- Anthony Pesquet
- Normandie Univ, UNILEHAVRE, CNRS, URCOM, 76600 Le Havre, France.
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26
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Placental Ras Regulates Inflammation Associated with Maternal Obesity. Mediators Inflamm 2018; 2018:3645386. [PMID: 30402038 PMCID: PMC6196914 DOI: 10.1155/2018/3645386] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Accepted: 09/11/2018] [Indexed: 02/07/2023] Open
Abstract
Heightened placental inflammation and dysfunction are commonly associated in pregnant obese women compared to their pregnant lean counterparts. The small GTPase superfamily members known as the rat sarcoma viral oncogene homolog (Ras) proteins, in particular, the K-Ras and H-Ras isoforms, have been implicated to regulate inflammation. The aims were to determine the placental Ras expression and activity with maternal obesity and its role in regulating placental inflammation. Human placenta was obtained at term Caesarean section from lean and obese pregnant women to determine the effect of maternal obesity on Ras protein expression and activity. To determine the effect of Ras on inflammation induced by bacterial endotoxin LPS and proinflammatory cytokines TNF-α or IL-1β, the chemical inhibitor lonafarnib (total Ras inhibitor) and siRNA (siKRAS and siHRAS) were used. Total Ras protein expression together with combined K-Ras and H-Ras activity was significantly increased in the placenta of obese pregnant women and when stimulated with LPS, IL-1β, or TNF-α. Lonafarnib significantly suppressed LPS-, IL-1β-, or TNF-α-induced IL-6, IL-8, MCP-1, and GRO-α expression and secretion in placental tissue. Primary trophoblast cells transfected with siKRAS or siHRAS demonstrated only K-Ras silencing significantly decreased IL-1β-, TNF-α-, or LPS-induced IL-6, IL-8, and MCP-1 expression and secretion. Furthermore, siKRAS significantly reduced downstream ERK-1/2 activation induced by LPS. In trophoblast cells, ERK-1/2 signalling is required for IL-6, IL-8, MCP-1, and GRO-α secretion. These studies implicate a role for K-Ras in regulating inflammation in human placenta. Suppressing overactive placental K-Ras function may prevent adverse fetal outcomes complicated by maternal obesity.
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27
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Abstract
The mechanistic target of rapamycin (mTOR) is an evolutionary conserved protein with a serine/threonine kinase activity that regulates cell growth, proliferation, motility, survival, protein synthesis, autophagy and transcription. It is embedded in 2 large protein complexes: mTORC1 and mTORC2. Regulation of specific mTOR pathway functions depends on multiple GTPases, that act either as regulators of mTOR protein complexes, coupling energy availability with mTORC1 activity, or as downstream effectors of both mTORC1 and mTORC2. In this commentary, we highlight the advantages of studying the mTOR pathway in C. elegans, including the subcellular localization of the signaling pathway components and the animal phenotypes following tissue specific protein over-expression or knockdown. One important regulator that is not limited to the mTOR pathway is RHEB. We discuss in vitro and in vivo data suggesting that RHEB can function as an inhibitor of mTOR when not bound to GTP. RHEB-1 itself is regulated by Rab GDP dissociation inhibitor β, which directly binds to ATX-2. We also highlight the roles of these proteins in dietary restriction-depended reduction in animal size and fat content.
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Affiliation(s)
- Daniel Z Bar
- a National Human Genome Research Institute, National Institutes of Health , Bethesda , MD , USA
| | - Chayki Charar
- b Department of Genetics , Institute of Life Sciences, Hebrew University of Jerusalem , Jerusalem , Israel
| | - Yosef Gruenbaum
- b Department of Genetics , Institute of Life Sciences, Hebrew University of Jerusalem , Jerusalem , Israel
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28
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Serna-Blasco R, Sanz-Álvarez M, Aguilera Ó, García-Foncillas J. Targeting the RAS-dependent chemoresistance: The Warburg connection. Semin Cancer Biol 2018; 54:80-90. [PMID: 29432815 DOI: 10.1016/j.semcancer.2018.01.016] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Revised: 01/24/2018] [Accepted: 01/29/2018] [Indexed: 02/07/2023]
Abstract
RAS protein family members (KRAS4A, KRAS4B, HRAS and NRAS) function as GDP-GTP-regulated on-off switches, which regulate cytoplasmic-nuclear signaling networks ruling diverse normal cellular processes. Constitutive activating mutations in RAS genes are found in up to 30% of human cancers, and remarkably, the oncogenic Ras mutations and mutations in other components of Ras/MAPK signaling pathways seem to be mutually exclusive in most tumors, pointing out that deregulation of Ras-dependent signaling is an essential requirement for tumorigenesis. Up to 30% of solid tumors are known to have a mutated (abnormal) KRAS gene. Unfortunately, patients harboring mutated KRAS CRC are unlikely to benefit from anti-EGFR therapy. Moreover, it remains unclear that patients with KRAS wild-type CRC will definitely respond to such therapies. Although some clinically designed-strategies to modulate KRAS aberrant activation have been designed, all attempts to target KRAS have failed in the clinical assays and K-RAS has been assumed to be invulnerable to chemotherapeutic attack. Recently, different encouraging publications reported that ascorbate may have a selective antitumoral effect on KRAS mutant cancer cells. In this review we aim to describe the prevalence and importance of KRAS mutation in cancer and associated problems for the clinical handling of patients harboring these tumors. We highlight the role of mutated KRAS in boosting and keeping the tumor associated aberrant cell metabolism stating that further in-depth studies on the molecular mechanism of ascorbate to bypass mutated KRAS-related metabolic alterations may constitute a new pathway to design novel molecules in order handle tumor resistance to anti EGFR-therapies.
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Affiliation(s)
- Roberto Serna-Blasco
- Translational Oncology Division, Oncohealth Institute, Fundacion Jimenez Diaz University Hospital, 28040, Madrid, Spain
| | - Marta Sanz-Álvarez
- Translational Oncology Division, Oncohealth Institute, Fundacion Jimenez Diaz University Hospital, 28040, Madrid, Spain
| | - Óscar Aguilera
- Translational Oncology Division, Oncohealth Institute, Fundacion Jimenez Diaz University Hospital, 28040, Madrid, Spain.
| | - Jesús García-Foncillas
- Translational Oncology Division, Oncohealth Institute, Fundacion Jimenez Diaz University Hospital, 28040, Madrid, Spain
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29
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Mahoney SJ, Narayan S, Molz L, Berstler LA, Kang SA, Vlasuk GP, Saiah E. A small molecule inhibitor of Rheb selectively targets mTORC1 signaling. Nat Commun 2018; 9:548. [PMID: 29416044 PMCID: PMC5803267 DOI: 10.1038/s41467-018-03035-z] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Accepted: 01/12/2018] [Indexed: 12/19/2022] Open
Abstract
The small G-protein Rheb activates the mechanistic target of rapamycin complex 1 (mTORC1) in response to growth factor signals. mTORC1 is a master regulator of cellular growth and metabolism; aberrant mTORC1 signaling is associated with fibrotic, metabolic, and neurodegenerative diseases, cancers, and rare disorders. Point mutations in the Rheb switch II domain impair its ability to activate mTORC1. Here, we report the discovery of a small molecule (NR1) that binds Rheb in the switch II domain and selectively blocks mTORC1 signaling. NR1 potently inhibits mTORC1 driven phosphorylation of ribosomal protein S6 kinase beta-1 (S6K1) but does not inhibit phosphorylation of AKT or ERK. In contrast to rapamycin, NR1 does not cause inhibition of mTORC2 upon prolonged treatment. Furthermore, NR1 potently and selectively inhibits mTORC1 in mouse kidney and muscle in vivo. The data presented herein suggest that pharmacological inhibition of Rheb is an effective approach for selective inhibition of mTORC1 with therapeutic potential.
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Affiliation(s)
- Sarah J Mahoney
- Navitor Pharmaceuticals, Inc., 1030 Massachusetts Ave. #410, Cambridge, MA, 02138, USA.
| | - Sridhar Narayan
- Navitor Pharmaceuticals, Inc., 1030 Massachusetts Ave. #410, Cambridge, MA, 02138, USA
| | - Lisa Molz
- Navitor Pharmaceuticals, Inc., 1030 Massachusetts Ave. #410, Cambridge, MA, 02138, USA
| | - Lauren A Berstler
- Navitor Pharmaceuticals, Inc., 1030 Massachusetts Ave. #410, Cambridge, MA, 02138, USA
| | - Seong A Kang
- Navitor Pharmaceuticals, Inc., 1030 Massachusetts Ave. #410, Cambridge, MA, 02138, USA
| | - George P Vlasuk
- Navitor Pharmaceuticals, Inc., 1030 Massachusetts Ave. #410, Cambridge, MA, 02138, USA
| | - Eddine Saiah
- Navitor Pharmaceuticals, Inc., 1030 Massachusetts Ave. #410, Cambridge, MA, 02138, USA
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30
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Wang J, Lian Y, Gu Y, Wang H, Gu L, Huang Y, Zhou L, Huang Y. Synergistic effect of farnesyl transferase inhibitor lonafarnib combined with chemotherapeutic agents against the growth of hepatocellular carcinoma cells. Oncotarget 2017; 8:105047-105060. [PMID: 29285232 PMCID: PMC5739619 DOI: 10.18632/oncotarget.22086] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Accepted: 10/12/2017] [Indexed: 12/29/2022] Open
Abstract
Hepatocellular carcinoma (HCC) is a common and deadly cancer worldwide and is often refractory to chemotherapy due to the development of multidrug resistance. Lonafarnib is an orally active and potent non-peptidomimetic inhibitor of farnesyl transferase. Here, using in vitro HCC cell models, we demonstrated that lonafarnib inhibited tumor proliferation and reduced the activity of mitogen-activated protein kinases pathways. In addition, lonafarnib caused G1 to S phase arrest through the downregulation of Cyclin D1, CDK6 and SKP2, while it induced cellular apoptosis by promoting the cleavage and activation of Caspase-3 and PARP. When combined with doxorubicin and sorafenib, lonafarnib was able to increase the sensitivity of HCC cells to chemotherapy. Furthermore, we also constructed ABCB1-overexpressing HCC cells and found that lonafarnib decreased chemoresistance by inhibiting ABCB1-mediated drug efflux activity. These results suggest that lonafarnib may be a promising synergistic agent for improving the treatment of drug-resistant HCC.
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Affiliation(s)
- Jialiang Wang
- Guangdong Provincial Key Laboratory of Liver Disease Research, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| | - Yifan Lian
- Guangdong Provincial Key Laboratory of Liver Disease Research, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| | - Yurong Gu
- Guangdong Provincial Key Laboratory of Liver Disease Research, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, China.,Department of Infectious Diseases, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| | - Hongbo Wang
- Guangdong Provincial Key Laboratory of Liver Disease Research, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| | - Lin Gu
- Guangdong Provincial Key Laboratory of Liver Disease Research, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| | - Yanlin Huang
- Department of Infectious Diseases, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| | - Liang Zhou
- Department of Infectious Diseases, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| | - Yuehua Huang
- Guangdong Provincial Key Laboratory of Liver Disease Research, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, China.,Department of Infectious Diseases, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
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31
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Gabriel D, Shafry DD, Gordon LB, Djabali K. Intermittent treatment with farnesyltransferase inhibitor and sulforaphane improves cellular homeostasis in Hutchinson-Gilford progeria fibroblasts. Oncotarget 2017; 8:64809-64826. [PMID: 29029393 PMCID: PMC5630293 DOI: 10.18632/oncotarget.19363] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2017] [Accepted: 06/29/2017] [Indexed: 11/25/2022] Open
Abstract
Hutchinson-Gilford progeria syndrome (HGPS) is a rare genetic condition associated with mutations in the LMNA gene. This disease recapitulates some aspects of normal aging, such as hair loss, thin skin, joint stiffness, and atherosclerosis. The latter leads to heart attack or stroke that causes death at an average age of 14.6 years in children with HGPS. The typical LMNA mutation results in the production of a truncated prelamin A protein, progerin, that remains permanently farnesylated and abnormally associated with the nuclear envelope. Farnesyltransferase inhibitors (FTIs) reverse nuclear structure abnormalities that are characteristic of HGPS cells. The first clinical trial using the FTI, Ionafarnib, demonstrated some improvements in HGPS children and, in particular, showed a decrease in arterial stiffness. Recently, we reported that sulforaphane, an antioxidant derived from cruciferous vegetables, efficiently stimulates autophagy and enhances progerin clearance in HGPS fibroblasts. In the present study, we investigated the effect of combined lonafarnib and sulforaphane treartment in HGPS fibroblast cultures. We report that co-administration of both drugs exerts a synergistic and additive positive effect on autophagy activity but was cytotoxic to HGPS cells. In contrast, intermittent treatment with lonafarnib followed by sulforaphane separately and in repeated cycles rescued the HGPS cellular phenotype. We propose that intermittent treatment with FTI and SFN separately might be a promising therapeutic avenue for children with HGPS.
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Affiliation(s)
- Diana Gabriel
- Department of Dermatology, Epigenetics of Aging, TUM School of Medicine, Technische Universität München, Garching-Munich, Germany
| | - Dinah Dorith Shafry
- Department of Dermatology, Epigenetics of Aging, TUM School of Medicine, Technische Universität München, Garching-Munich, Germany
| | - Leslie B Gordon
- Department of Pediatrics, Alpert Medical School of Brown University and Hasbro Children's Hospital, Providence, RI, USA.,Boston Children's Hospital and Harvard Medical School, Boston, MA, USA
| | - Karima Djabali
- Department of Dermatology, Epigenetics of Aging, TUM School of Medicine, Technische Universität München, Garching-Munich, Germany
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32
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Huang L, Jiang Y, Chen Y. Predicting Drug Combination Index and Simulating the Network-Regulation Dynamics by Mathematical Modeling of Drug-Targeted EGFR-ERK Signaling Pathway. Sci Rep 2017; 7:40752. [PMID: 28102344 PMCID: PMC5244366 DOI: 10.1038/srep40752] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Accepted: 12/06/2016] [Indexed: 02/05/2023] Open
Abstract
Synergistic drug combinations enable enhanced therapeutics. Their discovery typically involves the measurement and assessment of drug combination index (CI), which can be facilitated by the development and applications of in-silico CI predictive tools. In this work, we developed and tested the ability of a mathematical model of drug-targeted EGFR-ERK pathway in predicting CIs and in analyzing multiple synergistic drug combinations against observations. Our mathematical model was validated against the literature reported signaling, drug response dynamics, and EGFR-MEK drug combination effect. The predicted CIs and combination therapeutic effects of the EGFR-BRaf, BRaf-MEK, FTI-MEK, and FTI-BRaf inhibitor combinations showed consistent synergism. Our results suggest that existing pathway models may be potentially extended for developing drug-targeted pathway models to predict drug combination CI values, isobolograms, and drug-response surfaces as well as to analyze the dynamics of individual and combinations of drugs. With our model, the efficacy of potential drug combinations can be predicted. Our method complements the developed in-silico methods (e.g. the chemogenomic profile and the statistically-inferenced network models) by predicting drug combination effects from the perspectives of pathway dynamics using experimental or validated molecular kinetic constants, thereby facilitating the collective prediction of drug combination effects in diverse ranges of disease systems.
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Affiliation(s)
- Lu Huang
- The Ministry-Province Jointly Constructed Base for State Key Lab and Shenzhen Technology and Engineering Lab for Personalized Cancer Diagnostics and Therapeutics Tsinghua University Shenzhen Graduate School, and Shenzhen Kivita Innovative Drug Discovery Institute, Shenzhen, 518055, P.R. China
- Institute of Molecular Biology (IMB), Ackermannweg 4, 55128 Mainz, Germany
- Department of Pharmacy, and Center for Computational Science and Engineering, National University of Singapore, Blk S16, Level 8, 3 Science Drive 2, 117543 Singapore
| | - Yuyang Jiang
- The Ministry-Province Jointly Constructed Base for State Key Lab and Shenzhen Technology and Engineering Lab for Personalized Cancer Diagnostics and Therapeutics Tsinghua University Shenzhen Graduate School, and Shenzhen Kivita Innovative Drug Discovery Institute, Shenzhen, 518055, P.R. China
| | - Yuzong Chen
- Department of Pharmacy, and Center for Computational Science and Engineering, National University of Singapore, Blk S16, Level 8, 3 Science Drive 2, 117543 Singapore
- State Key Laboratory of Biotherapy, West China Hospital, West China School of Medicine, Sichuan University, Chengdu, China
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33
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Ataxia-telangiectasia mutated interactor regulates head and neck cancer metastasis via KRas expression. Oral Oncol 2016; 66:100-107. [PMID: 28012797 DOI: 10.1016/j.oraloncology.2016.11.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2016] [Revised: 11/04/2016] [Accepted: 11/13/2016] [Indexed: 01/27/2023]
Abstract
OBJECTIVES Relapse is the most serious problem affecting the morbidity and mortality rates of patients with head and neck squamous cell carcinoma (HNSCC). Although HNSCC has been studied for several decades, the exact mechanism of cancer recurrence remains unclear. MATERIALS AND METHODS ataxia-telangiectasia mutated interactor (ATMIN) messenger RNA(mRNA) expression was detected in HNSCC samples by quantitative RT-PCR, and was analyzed with patients' clinical outcomes by Kaplan-Meier analyses. The ectopic ATMIN expression or ATMIN silencing on invasion ability was evaluated in HNSCC cell lines. Lymph node metastasis ability was investigated by buccal orthotopic implantation in vivo. All statistical tests were two-sided. RESULTS ATMIN mRNA expression was positively correlated with patients' clinical outcomes. ATMIN blockage reduced invasion, migration, and metastasis abilities both in vitro and in vivo. Evidence from a buccal orthotopic implantation mice model showed that silenced ATMIN expression prolongs mice survival and reduced lymph node metastasis. In high-throughput microarray and bioinformative analyses, KRas was identified as a crucial downstream effector in ATMIN-mediated HNSCC metastasis and was positively associated with patients' clinical stages and ATMIN mRNA expression. CONCLUSIONS The role of ATMIN and its regulatory mechanisms in HNSCC progression are reported for the first time. The study results improve our understanding of the ATMIN-KRas axis leading to HNSCC migration or invasion and metastasis and facilitates the identification of possible therapy targets of downstream genes for designing effective therapeutic strategies in personalized medicine.
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34
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Franklin JL, Amsler MO, Messina JL. Prenylation differentially inhibits insulin-dependent immediate early gene mRNA expression. Biochem Biophys Res Commun 2016; 474:594-598. [PMID: 27086854 DOI: 10.1016/j.bbrc.2016.04.067] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Accepted: 04/13/2016] [Indexed: 12/15/2022]
Abstract
Increased activity of prenyl transferases is observed in pathological states of insulin resistance, diabetes, and obesity. Thus, functional inhibitors of farnesyl transferase (FTase) and geranylgeranyl transferase (GGTase) may be promising therapeutic treatments. We previously identified insulin responsive genes from a rat H4IIE hepatoma cell cDNA library, including β-actin, EGR1, Pip92, c-fos, and Hsp60. In the present study, we investigated whether acute treatment with FTase and GGTase inhibitors would alter insulin responsive gene initiation and/or elongation rates. We observed differential regulation of insulin responsive gene expression, suggesting a differential sensitivity of these genes to one or both of the specific protein prenylation inhibitors.
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Affiliation(s)
- J Lee Franklin
- University of Alabama at Birmingham, Department of Pathology, Division of Molecular and Cellular Pathology, Birmingham, AL 35294, USA
| | - Maggie O Amsler
- University of Alabama at Birmingham, Department of Biology, Birmingham, AL 35294, USA
| | - Joseph L Messina
- University of Alabama at Birmingham, Department of Pathology, Division of Molecular and Cellular Pathology, Birmingham, AL 35294, USA; Veterans Administration Medical Center, Birmingham, AL 35294, USA.
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35
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Mohanan Nair M, Zhao R, Xie X, Shen GX. Impact of glycated LDL on endothelial nitric oxide synthase in vascular endothelial cells: involvement of transmembrane signaling and endoplasmic reticulum stress. J Diabetes Complications 2016; 30:391-7. [PMID: 26853630 DOI: 10.1016/j.jdiacomp.2016.01.008] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Revised: 12/23/2015] [Accepted: 01/11/2016] [Indexed: 01/01/2023]
Abstract
Cardiovascular diseases are the major cause of mortality in diabetes patients. Increased levels of glycated low density lipoprotein (glyLDL) are detected in diabetic patients. Endothelial nitric oxide synthase (eNOS) generates nitric oxide, which is responsible to endothelium-dependent vasodilation. The impact of glyLDL on the expression and activity of eNOS in vascular endothelial cells (EC) remains unknown. The present study investigated the effect of glyLDL on the levels of protein, mRNA and activity of eNOS in cultured human umbilical vein EC. The results demonstrated that incubation of EC with physiological concentrations of glyLDL significantly reduced the abundances of eNOS protein in EC with the maximal inhibition at 100μg/ml for 24h. At the optimized condition, glyLDL decreased eNOS mRNA and reduced its activity in EC. Blocking antibody against the receptor for advanced glycation end products (RAGE) prevented glyLDL-induced downregulation of eNOS in EC. GlyLDL increased the translocation of H-Ras from cytoplasm to membrane in EC. Farnesyl-transferase inhibitor-276, an H-Ras antagonist, normalized glyLDL-induced downregulation of eNOS and prevented glyLDL-induced upregulation of H-Ras in EC membrane. Treatment with 4-phenylbutyric acid, an endoplasmic reticulum (ER) stress antagonist, prevented glyLDL-induced eNOS downregulation in EC. The results suggest that diabetes-associated metabolic stress inhibits the production and activity of eNOA in cultured human vascular EC through the activation of RAGE/H-Ras mediated upstream signaling pathway. ER stress induced by glyLDL is possibly involved in eNOS downregulation.
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Affiliation(s)
- Manoj Mohanan Nair
- Department of Physiology & Pathophysiology, University of Manitoba, Winnipeg, Canada
| | - Ruozhi Zhao
- Department of Internal Medicine, University of Manitoba, Winnipeg, Canada
| | - Xueping Xie
- Department of Internal Medicine, University of Manitoba, Winnipeg, Canada
| | - Garry X Shen
- Department of Physiology & Pathophysiology, University of Manitoba, Winnipeg, Canada; Department of Internal Medicine, University of Manitoba, Winnipeg, Canada.
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Tian Q, Smart JL, Clement JH, Wang Y, Derkatch A, Schubert H, Danilchik MV, Marks DL, Fedorov LM. RHEB1 expression in embryonic and postnatal mouse. Histochem Cell Biol 2015; 145:561-72. [PMID: 26708151 DOI: 10.1007/s00418-015-1394-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/08/2015] [Indexed: 12/16/2022]
Abstract
Ras homolog enriched in brain (RHEB1) is a member within the superfamily of GTP-binding proteins encoded by the RAS oncogenes. RHEB1 is located at the crossroad of several important pathways including the insulin-signaling pathways and thus plays an important role in different physiological processes. To understand better the physiological relevance of RHEB1 protein, the expression pattern of RHEB1 was analyzed in both embryonic (at E3.5-E16.5) and adult (1-month old) mice. RHEB1 immunostaining and X-gal staining were used for wild-type and Rheb1 gene trap mutant mice, respectively. These independent methods revealed similar RHEB1 expression patterns during both embryonic and postnatal developments. Ubiquitous uniform RHEB1/β-gal and/or RHEB1 expression was seen in preimplantation embryos at E3.5 and postimplantation embryos up to E12.5. Between stages E13.5 and E16.5, RHEB1 expression levels became complex: In particular, strong expression was identified in neural tissues, including the neuroepithelial layer of the mesencephalon, telencephalon, and neural tube of CNS and dorsal root ganglia. In addition, strong expression was seen in certain peripheral tissues including heart, intestine, muscle, and urinary bladder. Postnatal mice have broad spatial RHEB1 expression in different regions of the cerebral cortex, subcortical regions (including hippocampus), olfactory bulb, medulla oblongata, and cerebellum (particularly in Purkinje cells). Significant RHEB1 expression was also viewed in internal organs including the heart, intestine, urinary bladder, and muscle. Moreover, adult animals have complex tissue- and organ-specific RHEB1 expression patterns with different intensities observed throughout postnatal development. Its expression level is in general comparable in CNS and other organs of mouse. Thus, the expression pattern of RHEB1 suggests that it likely plays a ubiquitous role in the development of the early embryo with more tissue-specific roles in later development.
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Affiliation(s)
- Qi Tian
- OHSU Transgenic Mouse Models Shared Resource, Knight Cancer Institute, Oregon Health and Science University, 3181 SW Sam Jackson Park Road, Portland, OR, 97239, USA
| | | | - Joachim H Clement
- Department of Hematology and Oncology, Jena University Hospital, 07747, Jena, Germany
| | - Yingming Wang
- OHSU Transgenic Mouse Models Shared Resource, Knight Cancer Institute, Oregon Health and Science University, 3181 SW Sam Jackson Park Road, Portland, OR, 97239, USA
| | - Alex Derkatch
- OHSU Transgenic Mouse Models Shared Resource, Knight Cancer Institute, Oregon Health and Science University, 3181 SW Sam Jackson Park Road, Portland, OR, 97239, USA
| | | | - Michael V Danilchik
- Department of Integrative Biosciences, Oregon Health and Science University, Portland, OR, USA
| | - Daniel L Marks
- Department of Pediatrics, Oregon Health and Science University, Portland, OR, USA
| | - Lev M Fedorov
- OHSU Transgenic Mouse Models Shared Resource, Knight Cancer Institute, Oregon Health and Science University, 3181 SW Sam Jackson Park Road, Portland, OR, 97239, USA.
- Friedrich-Schiller-University, 07740, Jena, Germany.
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Armijo ME, Campos T, Fuentes-Villalobos F, Palma ME, Pincheira R, Castro AF. Rheb signaling and tumorigenesis: mTORC1 and new horizons. Int J Cancer 2015; 138:1815-23. [PMID: 26234902 DOI: 10.1002/ijc.29707] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2015] [Accepted: 07/22/2015] [Indexed: 01/05/2023]
Abstract
Rheb is a conserved small GTPase that belongs to the Ras superfamily, and is mainly involved in activation of cell growth through stimulation of mTORC1 activity. Because deregulation of the Rheb/mTORC1 signaling is associated with proliferative disorders and cancer, inhibition of mTORC1 has been therapeutically approached. Although this therapy has proven antitumor activity, its efficacy is not as expected. Here, we will review the main work on the identification of the role of Rheb in cell growth, and on the relevance of Rheb in proliferative disorders, including cancer. We will also review the Rheb functions that could explain tumor resistance to therapies with mTORC1 inhibitors, and will mainly focus our discussion on mTORC1-independent Rheb functions that could also be implicated in cancer cell survival and tumorigenesis. The current progress on the understanding of the noncanonical Rheb functions prompts future studies to establish their relevance in cancer and in the context of current cancer therapies.
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Affiliation(s)
- Marisol E Armijo
- Laboratorio de Transducción de Señales y Cáncer, Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Biológicas, Universidad De Concepción, Concepción, Chile
| | - Tania Campos
- Laboratorio de Transducción de Señales y Cáncer, Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Biológicas, Universidad De Concepción, Concepción, Chile
| | - Francisco Fuentes-Villalobos
- Laboratorio de Transducción de Señales y Cáncer, Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Biológicas, Universidad De Concepción, Concepción, Chile
| | - Mario E Palma
- Laboratorio de Transducción de Señales y Cáncer, Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Biológicas, Universidad De Concepción, Concepción, Chile
| | - Roxana Pincheira
- Laboratorio de Transducción de Señales y Cáncer, Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Biológicas, Universidad De Concepción, Concepción, Chile
| | - Ariel F Castro
- Laboratorio de Transducción de Señales y Cáncer, Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Biológicas, Universidad De Concepción, Concepción, Chile
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Bachmann HS, Meier W, du Bois A, Kimmig R, Kuhlmann JD, Siffert W, Sehouli J, Wollschlaeger K, Huober J, Hillemanns P, Burges A, Schmalfeldt B, Aminossadati B, Wimberger P. The FNTB promoter polymorphism rs11623866 as a potential predictive biomarker for lonafarnib treatment of ovarian cancer patients. Br J Clin Pharmacol 2015; 80:1139-48. [PMID: 26033044 DOI: 10.1111/bcp.12688] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Revised: 05/22/2015] [Accepted: 05/26/2015] [Indexed: 01/01/2023] Open
Abstract
AIM Despite promising preclinical findings regarding clinical utility of farnesyltransferase inhibitors (FTI), such as lonafarnib, success of clinical trials is limited. A multicentre AGO-OVAR-15 phase II trial reported an unfavourable effect of lonafarnib on the outcome of patients with advanced ovarian cancer. This study was performed as a genetic subgroup analysis of the AGO-OVAR-15 trial, and investigated the utility of the promoter polymorphism rs11623866 of the farnesyltransferase ß-subunit gene (FNTB) in predicting the clinical effectiveness of lonafarnib. METHODS The influence of rs11623866 (c.-609G > C) on FNTB promoter activity was investigated by electrophoretic-mobility-shift assay, luciferase-reporter assay and RT-qPCR. A total of 57 out of 105 patients from the AGO-OVAR-15 trial, treated with carboplatin and paclitaxel ± lonafarnib, was genotyped for rs11623866 by restriction fragment length polymorphism analysis. Genotype-dependent survival analysis was performed by Kaplan-Meier analysis. RESULTS The presence of the G allele was associated with increased FNTB promoter activity compared with the C allele. An unfavourable effect of lonafarnib was limited to patients carrying a GG genotype (HRPFS 6.2, 95%CI = 2.01, 19.41, P = 0.002; HROS 9.6, 95%CI = 1.89, 48.54, P = 0.006). Median progression free survival (PFS) for patients with the GG genotype in the lonafarnib treated arm was 10 months, whereas median PFS without FTI-treatment was 40 months. Median overall survival (OS) in the lonafarnib-treated group was 19 months, whereas median OS was not reached in the untreated group. CONCLUSIONS Discrepancies between preclinical success and clinical failure may be due to the patients' genetic variability of FNTB. Therefore, our results may encourage retrospective evaluation of FNTB polymorphisms in previous FTI studies, especially those reporting positive FTI response.
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Affiliation(s)
| | - Werner Meier
- Department of Gynecology and Obstetrics, Evangelisches Krankenhaus Duesseldorf, Dusseldorf
| | - Andreas du Bois
- Department of Gynecology and Gynecologic Oncology, Klinikum Essen Mitte, Essen
| | - Rainer Kimmig
- Department of Gynecology and Obstetrics, University of Duisburg-Essen, Essen
| | - Jan Dominik Kuhlmann
- Department of Gynecology and Obstetrics, University of Duisburg-Essen, Essen.,Department of Gynecology and Obstetrics Medical Faculty, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden.,German Cancer Consortium (DKTK), Dresden and German Cancer Research Center (DKFZ), Heidelberg
| | - Winfried Siffert
- Institute of Pharmacogenetics, University of Duisburg-Essen, Essen
| | - Jalid Sehouli
- Department of Gynecology, Charité Medical University of Berlin, Berlin
| | | | - Jens Huober
- Department of Gynecology and Obstetrics, University of Ulm, Ulm
| | - Peter Hillemanns
- Department of Gynecology and Obstetrics, Medical University of Hannover, Hannover
| | - Alexander Burges
- Department of Gynecology and Obstetrics, Klinikum Großhadern, Munich
| | | | - Behnaz Aminossadati
- Coordinating Centre for Clinical Trials (KKS), Philipps University of Marburg, Marburg, Germany
| | - Pauline Wimberger
- Department of Gynecology and Obstetrics, University of Duisburg-Essen, Essen.,Department of Gynecology and Obstetrics Medical Faculty, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden.,German Cancer Consortium (DKTK), Dresden and German Cancer Research Center (DKFZ), Heidelberg
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Abstract
New drugs targeting the mitogen-activated protein kinase (MAPK) pathway have generated striking clinical response in melanoma therapy. From the discovery of BRAF mutation in melanoma in 2002, to the approval of first BRAF inhibitor vemurafenib for melanoma treatment by the US Food and Drug Administration in 2011, therapies targeting the MAPK pathway have been proven effective in less than a decade. The success of vemurafenib stimulated more intensive investigation of the molecular mechanisms of melanoma pathogenesis and development of new treatment strategies targeting specific molecules in MAPK pathway. Although selective BRAF inhibitors and MEK inhibitors demonstrated improved overall survival of metastatic melanoma patients, limited duration or development of resistance to BRAF inhibitors have been reported. Patients with metastatic melanoma still face very poor prognosis and lack of clarified therapies. Studies and multiple clinical trials on more potent and selective small molecule inhibitory compounds to further improve the clinical effects and overcome drug resistance are underway. In this review, we analyzed the therapeutic potentials of each member of the MAPK signaling pathway, summarized important MAPK-inhibiting drugs, and discussed the promising combination treatment targeting multiple targets in melanoma therapy, which may overcome the drawbacks of current drugs treatment.
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Affiliation(s)
- Yabin Cheng
- Department of Dermatology and Skin Science, Research Pavilion, Vancouver Coastal Health Research Institute, University of British Columbia, Vancouver, BC, Canada
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Wang X, Wang Y, Zheng X, Hao X, Liang Y, Wu M, Wang X, Wang Z. Direct Interaction between Ras Homolog Enriched in Brain and FK506 Binding Protein 38 in Cashmere Goat Fetal Fibroblast Cells. ASIAN-AUSTRALASIAN JOURNAL OF ANIMAL SCIENCES 2014; 27:1671-7. [PMID: 25358358 PMCID: PMC4213676 DOI: 10.5713/ajas.2014.14145] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/26/2014] [Revised: 05/08/2014] [Accepted: 07/14/2014] [Indexed: 11/27/2022]
Abstract
Ras homolog enriched in brain (Rheb) and FK506 binding protein 38 (FKBP38) are two important regulatory proteins in the mammalian target of rapamycin (mTOR) pathway. There are contradictory data on the interaction between Rheb and FKBP38 in human cells, but this association has not been examined in cashmere goat cells. To investigate the interaction between Rheb and FKBP38, we overexpressed goat Rheb and FKBP38 in goat fetal fibroblasts, extracted whole proteins, and performed coimmunoprecipitation to detect them by western blot. We found Rheb binds directly to FKBP38. Then, we constructed bait vectors (pGBKT7-Rheb/FKBP38) and prey vectors (pGADT7-Rheb/FKBP38), and examined their interaction by yeast two-hybrid assay. Their direct interaction was observed, regardless of which plasmid served as the prey or bait vector. These results indicate that the 2 proteins interact directly in vivo. Novel evidence is presented on the mTOR signal pathway in Cashmere goat cells.
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Affiliation(s)
- Xiaojing Wang
- Chifeng Municipal Hospital, Chifeng, Inner Mongolia 024000, China
| | - Yanfeng Wang
- Chifeng Municipal Hospital, Chifeng, Inner Mongolia 024000, China
| | - Xu Zheng
- Chifeng Municipal Hospital, Chifeng, Inner Mongolia 024000, China
| | - Xiyan Hao
- Chifeng Municipal Hospital, Chifeng, Inner Mongolia 024000, China
| | - Yan Liang
- Chifeng Municipal Hospital, Chifeng, Inner Mongolia 024000, China
| | - Manlin Wu
- Chifeng Municipal Hospital, Chifeng, Inner Mongolia 024000, China
| | - Xiao Wang
- Chifeng Municipal Hospital, Chifeng, Inner Mongolia 024000, China
| | - Zhigang Wang
- Chifeng Municipal Hospital, Chifeng, Inner Mongolia 024000, China
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Yasuda S, Sugiura H, Katsurabayashi S, Shimada T, Tanaka H, Takasaki K, Iwasaki K, Kobayashi T, Hino O, Yamagata K. Activation of Rheb, but not of mTORC1, impairs spine synapse morphogenesis in tuberous sclerosis complex. Sci Rep 2014; 4:5155. [PMID: 24889507 PMCID: PMC4042127 DOI: 10.1038/srep05155] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2014] [Accepted: 05/15/2014] [Indexed: 12/30/2022] Open
Abstract
Mutations in the Tsc1 or Tsc2 genes cause tuberous sclerosis complex (TSC). Tsc1 and Tsc2 proteins form a complex that inhibits mammalian target of rapamycin complex 1 (mTORC1) signalling through Rheb-GTPase. We found that Tsc2+/− neurons showed impaired spine synapse formation, which was resistant to an mTORC1 inhibitor. Knockdown of mTOR also failed to restore these abnormalities, suggesting mTORC may not participate in impaired spinogenesis in Tsc2+/− neurons. To address whether Rheb activation impairs spine synapse formation, we expressed active and inactive forms of Rheb in WT and Tsc2+/− neurons, respectively. Expression of active Rheb abolished dendritic spine formation in WT neurons, whereas inactive Rheb restored spine synapse formation in Tsc2+/− neurons. Moreover, inactivation of Rheb with farnesyl transferase inhibitors recovered spine synapse morphogenesis in Tsc2+/− neurons. In conclusion, dendritic spine abnormalities in TSC neurons may be caused through activation of Rheb, but not through of mTORC1.
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Affiliation(s)
- Shin Yasuda
- 1] Neural Plasticity Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan [2]
| | - Hiroko Sugiura
- 1] Neural Plasticity Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan [2]
| | - Shutaro Katsurabayashi
- Department of Neuropharmacology, Faculty of Pharmaceutical Sciences, Fukuoka University, Fukuoka, Japan
| | - Tadayuki Shimada
- Neural Plasticity Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Hidekazu Tanaka
- Department of Biomedical Sciences, College of Life Sciences, Ritsumeikan University, Shiga, Japan
| | - Kotaro Takasaki
- Department of Neuropharmacology, Faculty of Pharmaceutical Sciences, Fukuoka University, Fukuoka, Japan
| | - Katsunori Iwasaki
- Department of Neuropharmacology, Faculty of Pharmaceutical Sciences, Fukuoka University, Fukuoka, Japan
| | - Toshiyuki Kobayashi
- Department of Pathology and Oncology, Juntendo University, School of Medicine, Tokyo, Japan
| | - Okio Hino
- Department of Pathology and Oncology, Juntendo University, School of Medicine, Tokyo, Japan
| | - Kanato Yamagata
- Neural Plasticity Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
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Abstract
Neuroblastoma (NB) is the most common extracranial malignant solid tumors of childhood, and the majority of these high-risk tumors is resistant to nearly all the treatments and has a significantly worse outcome. The mammalian target of rapamycin (mTOR) plays a critical role in oncogenesis and cancer progression of many tumors. This review will describe the function of mTOR, its genetic regulation in pediatric neuroblastoma, and its value as a target for inhibition by anticancer agents for patients with NB.
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Affiliation(s)
- Hong Mei
- 1Department of Pediatric Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
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Ganguly A, Chakraborty P, Banerjee K, Choudhuri SK. The role of a Schiff base scaffold, N-(2-hydroxy acetophenone) glycinate-in overcoming multidrug resistance in cancer. Eur J Pharm Sci 2013; 51:96-109. [PMID: 24044945 DOI: 10.1016/j.ejps.2013.09.003] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2013] [Revised: 08/16/2013] [Accepted: 09/03/2013] [Indexed: 01/01/2023]
Abstract
Drug resistance is a problem that hinders the numerous successes of chemotherapeutic intervention of cancer and continues to be a major obstacle for cures. Till date, several attempts have been made to develop suitable multidrug resistance (MDR) reversing agents. But, throughout the clinical development of MDR reversing agents, patients repeatedly suffer from toxicities. So far, some anticancer activity of Schiff bases which are the condensation products of carbonyl compounds and primary amines and their metal complexes has been described. But, overcoming multidrug resistance, by the use of such small molecules still remain unexplored. Under this backdrop, in search of less toxic and more effective MDR reversing agents our laboratory has developed the different metal chelates of Schiff base N-(2-hydroxy acetophenone)glycinate (NG) which is structurally similar to azatyrosine [L-β-(5-hydroxy-2-pyridyl)-alanine] that inhibits tumor formation by deactivating the c-Raf-1 kinase and c-Ha-ras signalling pathway. A decade-long research proposes possible strategies to overcome MDR by exploiting the chemical nature of such metal chelates. In this review we have catalogued the success of metal chelates of NG to overcome MDR in cancer. The review depict that the problem of MDR can be circumvent by synchronized activation of immunogenic cell death pathways that utilize the components of a host's immune system to kill cancer cells in combination with other conventional strategies. The current wealth of preclinical information promises better understanding of the cellular processes underlying MDR reversing activity of metal derivatives of NG and thus exposes several cellular targets for rational designing of new generation of Schiff base metal chelates as MDR reversing agents.
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Affiliation(s)
- Avishek Ganguly
- Department of In Vitro Carcinogenesis and Cellular Chemotherapy, Chittaranjan National Cancer Institute, Kolkata, India
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Ding H, McDonald JS, Yun S, Schneider PA, Peterson KL, Flatten KS, Loegering DA, Oberg AL, Riska SM, Huang S, Sinicrope FA, Adjei AA, Karp JE, Meng XW, Kaufmann SH. Farnesyltransferase inhibitor tipifarnib inhibits Rheb prenylation and stabilizes Bax in acute myelogenous leukemia cells. Haematologica 2013; 99:60-9. [PMID: 23996484 DOI: 10.3324/haematol.2013.087734] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Although farnesyltransferase inhibitors have shown promising activity in relapsed lymphoma and sporadic activity in acute myelogenous leukemia, their mechanism of cytotoxicity is incompletely understood, making development of predictive biomarkers difficult. In the present study, we examined the action of tipifarnib in human acute myelogenous leukemia cell lines and clinical samples. In contrast to the Ras/MEK/ERK pathway-mediated Bim upregulation that is responsible for tipifarnib-induced killing of malignant lymphoid cells, inhibition of Rheb-induced mTOR signaling followed by dose-dependent upregulation of Bax and Puma occurred in acute myelogenous leukemia cell lines undergoing tipifarnib-induced apoptosis. Similar Bax and Puma upregulation occurred in serial bone marrow samples harvested from a subset of acute myelogenous leukemia patients during tipifarnib treatment. Expression of FTI-resistant Rheb M184L, like knockdown of Bax or Puma, diminished tipifarnib-induced killing. Further analysis demonstrated that increased Bax and Puma levels reflect protein stabilization rather than increased gene expression. In U937 cells selected for tipifarnib resistance, neither inhibition of signaling downstream of Rheb nor Bax and Puma stabilization occurred. Collectively, these results not only identify a pathway downstream from Rheb that contributes to tipifarnib cytotoxicity in human acute myelogenous leukemia cells, but also demonstrate that FTI-induced killing of lymphoid versus myeloid cells reflects distinct biochemical mechanisms downstream of different farnesylated substrates. (ClinicalTrials.gov identifier NCT00602771).
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Wang L, Liu Q, Li F, Qiu J, Fan H, Ma H, Zhu Y, Wu L, Han X, Yang Z, Jiang H, Wei J, Xia H. Apoptosis induced by PGC-1β in breast cancer cells is mediated by the mTOR pathway. Oncol Rep 2013; 30:1631-8. [PMID: 23877360 DOI: 10.3892/or.2013.2628] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2013] [Accepted: 04/19/2013] [Indexed: 11/06/2022] Open
Abstract
The peroxisome proliferator-activated receptor-γ (PPAR-γ) coactivator-1β (PGC-1β) is a well-established regulator of mitochondrial biogenesis. However, the underlying mechanism of PGC-1β action remains elusive. This study reveals that knockdown of endogenous PGC-1β by short-hairpin RNA (shRNA) leads to a decrease in the expression of mammalian target of rapamycin (mTOR) pathway-related genes in MDA-MB-231 cells. After knockdown of PGC-1β, phosphorylation of AMP-activated protein kinase (AMPK), phosphorylation of Rictor on Thr1135, Raptor and S6 protein was inhibited. However, Akt phosphorylation on Ser473 was upregulated and cell apoptosis occurred. In particular, we demonstrate that the levels of PGC-1β and mTOR correlated with overall mitochondrial activity. These results provide new evidence that cell apoptosis is orchestrated by the balance between several signaling pathways, and that PGC-1β takes part in these events in breast cancer cells mediated by the mTOR signaling pathway.
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Affiliation(s)
- Libin Wang
- Life Science College, Shaanxi Normal University, Xi'an 710062, P.R. China
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Gajewski TF, Salama AKS, Niedzwiecki D, Johnson J, Linette G, Bucher C, Blaskovich MA, Sebti SM, Haluska F. Phase II study of the farnesyltransferase inhibitor R115777 in advanced melanoma (CALGB 500104). J Transl Med 2012; 10:246. [PMID: 23228035 PMCID: PMC3543225 DOI: 10.1186/1479-5876-10-246] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2012] [Accepted: 11/30/2012] [Indexed: 11/20/2022] Open
Abstract
Background Multiple farnesylated proteins are involved in signal transduction in cancer. Farnesyltransferase inhibitors (FTIs) have been developed as a strategy to inhibit the function of these proteins. As FTIs inhibit proliferation of melanoma cell lines, we undertook a study to assess the impact of a FTI in advanced melanoma. As farnesylated proteins are also important for T cell activation, measurement of effects on T cell function was also pursued. Methods A 3-stage trial design was developed with a maximum of 40 patients and early stopping if there were no responders in the first 14, or fewer than 2 responders in the first 28 patients. Eligibility included performance status of 0–1, no prior chemotherapy, at most 1 prior immunotherapy, no brain metastases, and presence of at least 2 cutaneous lesions amenable to biopsy. R115777 was administered twice per day for 21 days of a 28-day cycle. Patients were evaluated every 2 cycles by RECIST. Blood and tumor were analyzed pre-treatment and during week 7. Results Fourteen patients were enrolled. Two patients had grade 3 toxicities, which included myelosuppression, nausea/vomiting, elevated BUN, and anorexia. There were no clinical responses. All patients analyzed showed potent inhibition of FT activity (85-98%) in tumor tissue; inhibition of phosphorylated ERK and Akt was also observed. T cells showed evidence of FT inhibition and diminished IFN-γ production. Conclusions Despite potent target inhibition, R115777 showed no evidence of clinical activity in this cohort of melanoma patients. Inhibition of T cell function by FTIs has potential clinical implications. Clinicaltrials.gov number NCT00060125
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Affiliation(s)
- Thomas F Gajewski
- The University of Chicago, Section of Hematology/Oncology, 5841 S, Maryland Ave, MC2115, Chicago, IL 60637, USA.
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Liu W, Zhou J, Zhang T, Zhang H, Zhu H, Cheng Y, Gust R. Synthesis and biological evaluation of cyanoguanidine derivatives of loratadine. Bioorg Med Chem Lett 2012; 22:6076-80. [PMID: 22959205 DOI: 10.1016/j.bmcl.2012.08.041] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2012] [Accepted: 08/10/2012] [Indexed: 11/25/2022]
Abstract
Cyanoguanidine derivatives of loratadine (3a-i) were synthesized and screened for antitumor and anti-inflammatory activity. The most promising compound 3c (R=n-C(8)H(17)) possessed at least twofold higher in vitro cytotoxicity than 5-fluorouracil against mammary (MCF-7 and MDA-MB 231) as well as colon (HT-29) carcinoma cells. The mode of action, however, is so far unclear. The participation of the COX-1/2 enzymes on the cytotoxicity, however, is very unlikely. Nevertheless all compounds showed stronger in vivo anti-inflammatory activity than ibuprofen in the xylene-induced ear swelling assay in mice.
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Affiliation(s)
- Wukun Liu
- Department of Medicinal Chemistry, China Pharmaceutical University, Tongjia Xiang 24, 210009 Nanjing, PR China
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Meier W, du Bois A, Rau J, Gropp-Meier M, Baumann K, Huober J, Wollschlaeger K, Kreienberg R, Canzler U, Schmalfeldt B, Wimberger P, Richter B, Schröder W, Belau A, Stähle A, Burges A, Sehouli J. Randomized phase II trial of carboplatin and paclitaxel with or without lonafarnib in first-line treatment of epithelial ovarian cancer stage IIB–IV. Gynecol Oncol 2012; 126:236-40. [DOI: 10.1016/j.ygyno.2012.04.050] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2012] [Revised: 04/30/2012] [Accepted: 04/30/2012] [Indexed: 11/27/2022]
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Is there a future for prenyltransferase inhibitors in cancer therapy? Curr Opin Pharmacol 2012; 12:704-9. [PMID: 22817869 DOI: 10.1016/j.coph.2012.06.013] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2012] [Accepted: 06/29/2012] [Indexed: 11/23/2022]
Abstract
It has been over 20 years since it was first recognized that the function of both normal and oncogenic Ras is dependent on the post-translational modification termed farnesylation. Since that time, intense effort has been expended on the development of farnesyltransferase inhibitors as novel anticancer agents. Over 70 clinical trials have now been conducted, with limited efficacy demonstrated. Here we provide an update of the most recently published clinical trials, discuss the use of the RASGRP1/APTX two-gene expression screen to select patients with acute myeloid leukemia for therapy, and report on the latest discoveries related to the targets of prenyltransferase inhibitors.
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