1
|
John AJ, Ghose ET, Gao H, Luck M, Jeong D, Kalari KR, Wang L. ReCorDE: a framework for identifying drug classes targeting shared vulnerabilities with applications to synergistic drug discovery. Front Oncol 2024; 14:1343091. [PMID: 38884087 PMCID: PMC11176476 DOI: 10.3389/fonc.2024.1343091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Accepted: 04/18/2024] [Indexed: 06/18/2024] Open
Abstract
Cancer is typically treated with combinatorial therapy, and such combinations may be synergistic. However, discovery of these combinations has proven difficult as brute force combinatorial screening approaches are both logistically complex and resource-intensive. Therefore, computational approaches to augment synergistic drug discovery are of interest, but current approaches are limited by their dependencies on combinatorial drug screening training data or molecular profiling data. These dataset dependencies can limit the number and diversity of drugs for which these approaches can make inferences. Herein, we describe a novel computational framework, ReCorDE (Recurrent Correlation of Drugs with Enrichment), that uses publicly-available cell line-derived monotherapy cytotoxicity datasets to identify drug classes targeting shared vulnerabilities across multiple cancer lineages; and we show how these inferences can be used to augment synergistic drug combination discovery. Additionally, we demonstrate in preclinical models that a drug class combination predicted by ReCorDE to target shared vulnerabilities (PARP inhibitors and Aurora kinase inhibitors) exhibits class-class synergy across lineages. ReCorDE functions independently of combinatorial drug screening and molecular profiling data, using only extensive monotherapy cytotoxicity datasets as its input. This allows ReCorDE to make robust inferences for a large, diverse array of drugs. In conclusion, we have described a novel framework for the identification of drug classes targeting shared vulnerabilities using monotherapy cytotoxicity datasets, and we showed how these inferences can be used to aid discovery of novel synergistic drug combinations.
Collapse
Affiliation(s)
- August J John
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN, United States
| | - Emily T Ghose
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN, United States
| | - Huanyao Gao
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN, United States
| | - Meagan Luck
- Department of Biological Sciences, University of Notre Dame, South Bend, IN, United States
| | - Dabin Jeong
- Biochemistry Department, Lawrence University, Appleton, WI, United States
| | - Krishna R Kalari
- Department of Quantitative Health Sciences, Mayo Clinic, Rochester, MN, United States
| | - Liewei Wang
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN, United States
| |
Collapse
|
2
|
Gassib N, Issa H, Loubaki L, Behaz S, Almutairi MH, Rouabhia M, Semlali A. Cellular mechanisms mediating the anti-cancer effects of carnosol on gingiva carcinoma. Sci Rep 2024; 14:12266. [PMID: 38806527 PMCID: PMC11133392 DOI: 10.1038/s41598-024-60797-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Accepted: 04/26/2024] [Indexed: 05/30/2024] Open
Abstract
Carnosol, a rosemary polyphenol, displays anticancer properties and is suggested as a safer alternative to conventional surgery, radiotherapy, and chemotherapy. Given that its effects on gingiva carcinoma have not yet been investigated, the aim of this study was to explore its anti-tumor selectivity and to unravel its underlying mechanisms of action. Hence, oral tongue and gingiva carcinoma cell lines exposed to carnosol were analyzed to estimate cytotoxicity, cell viability, cell proliferation, and colony formation potential as compared with those of normal cells. Key cell cycle and apoptotic markers were also measured. Finally, cell migration, oxidative stress, and crucial cell signaling pathways were assessed. Selective anti-gingiva carcinoma activity was disclosed. Overall, carnosol mediated colony formation and proliferation suppression in addition to cytotoxicity induction. Cell cycle arrest was highlighted by the disruption of the c-myc oncogene/p53 tumor suppressor balance. Carnosol also increased apoptosis, oxidative stress, and antioxidant activity. On a larger scale, the alteration of cell cycle and apoptotic profiles was also demonstrated by QPCR array. This was most likely achieved by controlling the STAT5, ERK1/2, p38, and NF-ĸB signaling pathways. Lastly, carnosol reduced inflammation and invasion ability by modulating IL-6 and MMP9/TIMP-1 axes. This study establishes a robust foundation, urging extensive inquiry both in vivo and in clinical settings, to substantiate the efficacy of carnosol in managing gingiva carcinoma.
Collapse
Affiliation(s)
- Nassima Gassib
- Groupe de recherche en écologie buccale, Faculté de médecine dentaire, Université Laval, Québec, QC, G1V 0A6, Canada
| | - Hawraa Issa
- Groupe de recherche en écologie buccale, Faculté de médecine dentaire, Université Laval, Québec, QC, G1V 0A6, Canada
| | - Lionel Loubaki
- Héma-Québec, 1070, Avenue des Sciences-de-la-Vie, Québec, QC, G1V 5C3, Canada
| | - Sarah Behaz
- Groupe de recherche en écologie buccale, Faculté de médecine dentaire, Université Laval, Québec, QC, G1V 0A6, Canada
| | - Mikhlid H Almutairi
- Zoology Department, College of Science, King Saud University, P.O. Box 2455, 11451, Riyadh, Saudi Arabia
| | - Mahmoud Rouabhia
- Groupe de recherche en écologie buccale, Faculté de médecine dentaire, Université Laval, Québec, QC, G1V 0A6, Canada
| | - Abdelhabib Semlali
- Groupe de recherche en écologie buccale, Faculté de médecine dentaire, Université Laval, Québec, QC, G1V 0A6, Canada.
| |
Collapse
|
3
|
Sangthong J, Thuwajit C, Jensen LT, Komyod W, Yuvaniyama J, Ponglikitmongkol M. BRCA1 deficiency enhances the aggressiveness of breast cancer cells expressing HPV16 oncoproteins. Biol Cell 2024; 116:e202300072. [PMID: 38514439 DOI: 10.1111/boc.202300072] [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: 08/20/2023] [Revised: 02/22/2024] [Accepted: 02/28/2024] [Indexed: 03/23/2024]
Abstract
BACKGROUND INFORMATION The precise etiology of breast cancer is not completely understood, although women with BRCA1 gene mutations have a significantly increased risk of developing the disease. In addition, sporadic breast cancer is frequently associated with decreased BRCA1 gene expression. Growing evidence of Human papillomaviruses (HPVs) infections in breast tumors has raised the possibility of the involvement of HPVs in the pathogenesis of breast cancer. We investigated whether the effects of HPV oncoproteins E6 and E7 were influenced by the expression levels of BRCA1. HPV16E6E7 (prototype or E6D25E/E7N29S Asian variant type) were stably expressed in MDA-MB231 breast cancer cells, wild type for BRCA1, or with BRCA1 knocked down. RESULTS Expression of HPV16E6E7 oncogenes did not affect BRCA1 levels and the abundance of HPV16E6E7 was not altered by BRCA1 knockdown. BRCA1 levels did not alter HPV16E6E7-dependent degradation of G1-S cell cycle proteins p53 and pRb. However, we found that the expression of G2-M cell cycle protein cyclin B1 enhanced by HPV16E6E7 was impacted by BRCA1 levels. Especially, we found the correlation between BRCA1 and cyclin B1 expression and this was also confirmed in breast cancer samples from a Thai cohort. We further demonstrated that the combination of HPV oncoproteins and low levels of BRCA1 protein appears to enhance proliferation and invasion. Transactivation activities of HPV16E6E7 on genes regulating cell proliferation and invasion (TGF-β and vimentin) were significantly increased in BRCA1-deficient cells. CONCLUSIONS Our results indicate that a deficiency of BRCA1 promotes the transactivation activity of HPV16E6E7 leading to increase of cell proliferation and invasion. SIGNIFICANCE HPV infection appears to have the potential to enhance the aggressiveness of breast cancers, especially those deficient in BRCA1.
Collapse
Affiliation(s)
- Jariya Sangthong
- Faculty of Science, Graduate Program in Molecular Medicine, Mahidol University, Bangkok, Thailand
| | - Chanitra Thuwajit
- Department of Immunology, Faculty of Medicine Siriraj Hospital, Bangkok, Thailand
| | - Laran T Jensen
- Faculty of Science, Department of Biochemistry, Mahidol University, Bangkok, Thailand
| | - Waraporn Komyod
- Faculty of Science, Department of Biochemistry, Mahidol University, Bangkok, Thailand
| | - Jirundon Yuvaniyama
- Faculty of Science, Department of Biochemistry, Mahidol University, Bangkok, Thailand
| | | |
Collapse
|
4
|
Matthäus T, Stößer S, Seren HY, Haberland VMM, Hartwig A. Arsenite Impairs BRCA1-Dependent DNA Double-Strand Break Repair, a Mechanism Potentially Contributing to Genomic Instability. Int J Mol Sci 2023; 24:14395. [PMID: 37762697 PMCID: PMC10532266 DOI: 10.3390/ijms241814395] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Revised: 09/15/2023] [Accepted: 09/18/2023] [Indexed: 09/29/2023] Open
Abstract
BRCA1 is a key player in maintaining genomic integrity with multiple functions in DNA damage response (DDR) mechanisms. Due to its thiol-rich zinc-complexing domain, the protein may also be a potential target for redox-active and/or thiol-reactive (semi)metal compounds. The latter includes trivalent inorganic arsenic, which is indirectly genotoxic via induction of oxidative stress and inhibition of DNA repair pathways. In the present study, we investigated the effect of NaAsO2 on the transcriptional and functional DDR. Particular attention was paid to the potential impairment of BRCA1-mediated DDR mechanisms by arsenite by comparing BRCA1-deficient and -proficient cells. At the transcriptional level, arsenite itself activated several DDR mechanisms, including a pronounced oxidative stress and DNA damage response, mostly independent of BRCA1 status. However, at the functional level, a clear BRCA1 dependency was observed in both cell cycle regulation and cell death mechanisms after arsenite exposure. Furthermore, in the absence of arsenite, the lack of functional BRCA1 impaired the largely error-free homologous recombination (HR), leading to a shift towards the error-prone non-homologous end-joining (NHEJ). Arsenic treatment also induced this shift in BRCA1-proficient cells, indicating BRCA1 inactivation. Although BRCA1 bound to DNA DSBs induced via ionizing radiation, its dissociation was impaired, similarly to the downstream proteins RAD51 and RAD54. A shift from HR to NHEJ by arsenite was further supported by corresponding reporter gene assays. Taken together, arsenite appears to negatively affect HR via functional inactivation of BRCA1, possibly by interacting with its RING finger structure, which may compromise genomic stability.
Collapse
Affiliation(s)
| | | | | | | | - Andrea Hartwig
- Department of Food Chemistry and Toxicology, Institute of Applied Biosciences (IAB), Karlsruhe Institute of Technology (KIT), Adenauerring 20a, 76131 Karlsruhe, Germany
| |
Collapse
|
5
|
Paccosi E, Artemi G, Filippi S, Balzerano A, Costanzo F, Laghezza-Masci V, Proietti S, Proietti-De-Santis L. Cockayne syndrome group A protein localizes at centrosomes during mitosis and regulates Cyclin B1 ubiquitination. Eur J Cell Biol 2023; 102:151325. [PMID: 37216802 DOI: 10.1016/j.ejcb.2023.151325] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Revised: 05/16/2023] [Accepted: 05/18/2023] [Indexed: 05/24/2023] Open
Abstract
Mutations in CSA and CSB proteins cause Cockayne syndrome, a rare genetic neurodevelopment disorder. Alongside their demonstrated roles in DNA repair and transcription, these two proteins have recently been discovered to regulate cytokinesis, the final stage of the cell division. This last finding allowed, for the first time, to highlight an extranuclear localization of CS proteins, beyond the one already known at mitochondria. In this study, we demonstrated an additional role for CSA protein being recruited at centrosomes in a strictly determined step of mitosis, which ranges from pro-metaphase until metaphase exit. Centrosomal CSA exerts its function in specifically targeting the pool of centrosomal Cyclin B1 for ubiquitination and proteasomal degradation. Interestingly, a lack of CSA recruitment at centrosomes does not affect Cyclin B1 centrosomal localization but, instead, it causes its lasting centrosomal permanence, thus inducing Caspase 3 activation and apoptosis. The discovery of this unveiled before CSA recruitment at centrosomes opens a new and promising scenario for the understanding of some of the complex and different clinical aspects of Cockayne Syndrome.
Collapse
Affiliation(s)
- Elena Paccosi
- Unit of Molecular Genetics of Aging, Department of Ecology and Biology (DEB), University of Tuscia, 01100 Viterbo, Italy
| | - Giulia Artemi
- Unit of Molecular Genetics of Aging, Department of Ecology and Biology (DEB), University of Tuscia, 01100 Viterbo, Italy
| | - Silvia Filippi
- Unit of Molecular Genetics of Aging, Department of Ecology and Biology (DEB), University of Tuscia, 01100 Viterbo, Italy
| | - Alessio Balzerano
- Unit of Molecular Genetics of Aging, Department of Ecology and Biology (DEB), University of Tuscia, 01100 Viterbo, Italy
| | - Federico Costanzo
- Faculty of Biomedical Sciences, Institute of Oncology Research, USI, Bellinzona, TI, 6500, Switzerland
| | - Valentina Laghezza-Masci
- Department for Innovation in Biological, Agro-Food and Forest Systems (DIBAF), University of Tuscia, Largo dell'Università, 01100 Viterbo, Italy
| | - Silvia Proietti
- Department of Ecological and Biological Sciences, University of Tuscia, 01100 Viterbo, Italy
| | - Luca Proietti-De-Santis
- Unit of Molecular Genetics of Aging, Department of Ecology and Biology (DEB), University of Tuscia, 01100 Viterbo, Italy.
| |
Collapse
|
6
|
Ouyang G, Fu W, Guo J, Lu Q, Yao Y, Ge L, Zhao J, Zhang J, Hu X, Li S, Xu Q, Huang D, Zhang Y. Hypoxia-induced UBE2K promotes the malignant progression of HCC. Pathol Res Pract 2023; 245:154422. [PMID: 37003132 DOI: 10.1016/j.prp.2023.154422] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/28/2022] [Revised: 02/18/2023] [Accepted: 03/20/2023] [Indexed: 03/28/2023]
Abstract
BACKGROUND Hypoxia critically drives malignant tumor development and is characteristic of hepatocellular carcinoma (HCC), where HIF-1α plays a crucial role. The ubiquitin-conjugating enzyme E2K (UBE2K) is known to participate in the advancement of several human cancers. However, the role of UBE2K in HCC or whether it is a hypoxia-responsive gene remains to be further identified. METHOD We performed a microarray to measure the gene expression differences between normoxia and hypoxia. CoCl2 mimicked the hypoxic condition. The protein and RNA expression of HIF-1α, UBE2K, and Actin in HCC cells were measured by western blotting(WB) and RT-qPCR, respectively. Immunohistochemical (IHC) staining analyzed the expression of UBE2K and HIF-1α in HCC tissues. CCK-8 and colony formation assay evaluated the HCC cell growth. Scratch healing and transwell assays were used to detect the migration capability of the cells. Lipofectamine 3000 was used to transfect the plasmids or siRNAs to HCC cells. RESULTS We identified UBE2K as a potential hypoxia-responsive gene. Our study showed that hypoxia induced HIF-1α-mediated increase of UBE2K levels in HCC cells, which decreased under HIF-1α deficiency under hypoxia. Further bioinformatics analysis based on UALCAN and GEPIA databases confirmed that UBE2K was highly expressed in HCC tissues and positively associated with HIF-1α expression. Functionally, Hep3B and Huh7 cell proliferation and migration were stimulated upon UBE2K overexpression, while the UBE2K knockdown suppressed such effect. Furthermore, functional rescue experiment proved that depletion of UBE2K inhibited hypoxia-induced cell proliferation and migration in HCC cells. In contrast, enhancing UBE2K levels rescued cell proliferation and migration repression caused by HIF-1α deficiency in hypoxia. CONCLUSION Our results established UBE2K as a potential hypoxia-inducible gene in HCC cells, positively regulated by HIF-1α in hypoxia. Moreover, UBE2K served as an oncogene and cooperated with HIF-1α to form a functional HIF-1α/UBE2K axis to trigger HCC progression, highlighting a potential application of UBE2K as a therapeutic target for HCC treatment.
Collapse
|
7
|
Molinaro C, Wambang N, Bousquet T, Vercoutter-Edouart AS, Pélinski L, Cailliau K, Martoriati A. A Novel Copper(II) Indenoisoquinoline Complex Inhibits Topoisomerase I, Induces G2 Phase Arrest, and Autophagy in Three Adenocarcinomas. Front Oncol 2022; 12:837373. [PMID: 35280788 PMCID: PMC8908320 DOI: 10.3389/fonc.2022.837373] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Accepted: 01/26/2022] [Indexed: 12/30/2022] Open
Abstract
Topoisomerases, targets of inhibitors used in chemotherapy, induce DNA breaks accumulation leading to cancer cell death. A newly synthesized copper(II) indenoisoquinoline complex WN197 exhibits a cytotoxic effect below 0.5 µM, on MDA-MB-231, HeLa, and HT-29 cells. At low doses, WN197 inhibits topoisomerase I. At higher doses, it inhibits topoisomerase IIα and IIβ, and displays DNA intercalation properties. DNA damage is detected by the presence of γH2AX. The activation of the DNA Damage Response (DDR) occurs through the phosphorylation of ATM/ATR, Chk1/2 kinases, and the increase of p21, a p53 target. WN197 induces a G2 phase arrest characterized by the unphosphorylated form of histone H3, the accumulation of phosphorylated Cdk1, and an association of Cdc25C with 14.3.3. Cancer cells die by autophagy with Beclin-1 accumulation, LC3-II formation, p62 degradation, and RAPTOR phosphorylation in the mTOR complex. Finally, WN197 by inhibiting topoisomerase I at low concentration with high efficiency is a promising agent for the development of future DNA damaging chemotherapies.
Collapse
Affiliation(s)
- Caroline Molinaro
- Univ. Lille, CNRS, UMR 8576-UGSF-Unité de Glycobiologie Structurale et Fonctionnelle, Lille, France
| | | | - Till Bousquet
- Univ. Lille, CNRS, Centrale Lille, Univ. Artois, UMR 8181-UCCS-Unité de Catalyse et Chimie du Solide, Lille, France
| | | | - Lydie Pélinski
- Univ. Lille, CNRS, Centrale Lille, Univ. Artois, UMR 8181-UCCS-Unité de Catalyse et Chimie du Solide, Lille, France
| | - Katia Cailliau
- Univ. Lille, CNRS, UMR 8576-UGSF-Unité de Glycobiologie Structurale et Fonctionnelle, Lille, France
| | - Alain Martoriati
- Univ. Lille, CNRS, UMR 8576-UGSF-Unité de Glycobiologie Structurale et Fonctionnelle, Lille, France
| |
Collapse
|
8
|
Thai SF, Jones CP, Robinette BL, Ren H, Vallanat B, Fisher AA, Kitchin KT. Effects of Silver Nanoparticles and Silver Nitrate on mRNA and microRNA Expression in Human Hepatocellular Carcinoma Cells (HepG2). JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2021; 21:5414-5428. [PMID: 33980351 PMCID: PMC10563035 DOI: 10.1166/jnn.2021.19481] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
In order to understand toxicity of nano silver, human hepatocellular carcinoma (HepG2) cells were treated either with silver nitrate (AgNO₃) or with nano silver capped with glutathione (Ag-S) at various concentration. Differentially expressed genelists for mRNA and microRNA were obtained through Illumina RNA sequencing and DEseq data analyses. Both treatments showed non-linear dose response relationships for mRNA and microRNA. Gene expression analysis showed signaling pathways common to both nano Ag-S and AgNO₃, such as cell cycle regulation, DNA damage response and cancer related pathways. But, nano Ag-S caused signaling pathway changes that were not altered by AgNO₃ such as NRF2-mediated oxidative stress response inflammation, cell membrane signaling, and cell proliferation. Nano Ag-S also affected p53 signaling, survival, apoptosis, tissue repair, lipid synthesis, angiogenesis, liver fibrosis and tumor development. Several of the pathways affected by nano Ag-S are hypothesized as major contributors to nanotoxicity. MicroRNA target filter analysis revealed additional affected pathways that were not reflected in the mRNA expression response alone, including DNA damage signaling, genomic stability, ROS, cell cycle, ubiquitination, DNA methylation, cell proliferation and fibrosis for AgNO₃; and cell cycle regulation, P53 signaling, cell proliferation, survival, apoptosis, tissue repair and so on for nano Ag-S. These pathways may be mediated by microRNA repression of protein translation.Our study clearly showed that the addition of microRNA profiling increased the numbers of signaling pathways discovered that affected by the treatments on HepG2 cells and gave US a better picture of the effects of these reagents in the cells.
Collapse
Affiliation(s)
- Sheau-Fung Thai
- Center for Computational Toxicology and Exposure, US Environmental Protection Agency, 109 TWAlexander Dr, Durham NC 27709, USA
| | - Carlton P Jones
- Center for Computational Toxicology and Exposure, US Environmental Protection Agency, 109 TWAlexander Dr, Durham NC 27709, USA
| | - Brian L Robinette
- Center for Computational Toxicology and Exposure, US Environmental Protection Agency, 109 TWAlexander Dr, Durham NC 27709, USA
| | - Hongzu Ren
- Center for Public Health and Environmental Assessment, US Environmental Production Agency, 109 TW Alexander Dr., Durham NC 27709, USA
| | | | - Anna A Fisher
- Center for Public Health and Environmental Assessment, US Environmental Production Agency, 109 TW Alexander Dr., Durham NC 27709, USA
| | - Kirk T Kitchin
- US Environmental Protection Agency, Retired from EPA, Durham NC 27709, USA
| |
Collapse
|
9
|
The BRCA1/BARD1 ubiquitin ligase and its substrates. Biochem J 2021; 478:3467-3483. [PMID: 34591954 DOI: 10.1042/bcj20200864] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Revised: 09/03/2021] [Accepted: 09/07/2021] [Indexed: 12/19/2022]
Abstract
Mutations in breast cancer type 1 susceptibility protein (BRCA1) and its heterodimeric binding partner BARD1 confer a high risk for the development of breast and ovarian cancers. The sole enzymatic function of the BRCA1/BARD1 complex is as a RING-type E3 ubiquitin (Ub) ligase, leading to the deposition of Ub signals onto a variety of substrate proteins. Distinct types of Ub signals deposited by BRCA1/BARD1 (i.e. degradative vs. non-degradative; mono-Ub vs. poly-Ub chains) on substrate proteins mediate aspects of its function in DNA double-stranded break repair, cell-cycle regulation, and transcriptional regulation. While cancer-predisposing mutations in both subunits lead to the inactivation of BRCA1/BARD1 ligase activity, controversy remains as to whether its Ub ligase activity directly inhibits tumorigenesis. Investigation of BRCA1/BARD1 substrates using rigorous, well-validated mutants and experimental systems will ultimately clarify the role of its ligase activity in cancer and possibly establish prognostic and diagnostic metrics for patients with mutations. In this review, we discuss the Ub ligase function of BRCA1/BARD1, highlighting experimental approaches, mechanistic considerations, and reagents that are useful in the study of substrate ubiquitylation. We also discuss the current understanding of two well-established BRCA1/BARD1 substrates (nucleosomal H2A and estrogen receptor α) and several recently discovered substrates (p50, NF2, Oct1, and LARP7). Lessons from the current body of work should provide a road map to researchers examining novel substrates and biological functions attributed to BRCA1/BARD1 Ub ligase activity.
Collapse
|
10
|
Gillani SQ, Nisa MU, Sarwar Z, Reshi I, Bhat SA, Nabi N, Andrabi S. Regulation of PCTAIRE1 protein stability by AKT1, LKB1 and BRCA1. Cell Signal 2021; 85:110032. [PMID: 33932497 DOI: 10.1016/j.cellsig.2021.110032] [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: 01/09/2021] [Revised: 04/23/2021] [Accepted: 04/26/2021] [Indexed: 10/21/2022]
Abstract
PCTAIRE1, also known as CDK16, is a cyclin-dependent kinase that is regulated by cyclin Y. It is a member of the serine-threonine family of kinases and its functions have primarily been implicated in cellular processes like vesicular transport, neuronal growth and development, myogenesis, spermatogenesis and cell proliferation. However, as extensive studies on PCTAIRE1 have not yet been conducted, the signaling pathways for this kinase involved in governing many cellular processes are yet to be elucidated in detail. Here, we report the association of PCTAIRE1 with important cellular proteins involved in major cell signaling pathways, especially cell proliferation. In particular, here we show that PCTAIRE1 interacts with AKT1, a key player of the PI3K signaling pathway that is responsible for promoting cell survival and proliferation. Our studies show that PCTAIRE1 is a substrate of AKT1 that gets stabilized by it. Further, we show that PCTAIRE1 also interacts with and is degraded by LKB1, a kinase that is known to suppress cellular proliferation and also regulate cellular energy metabolism. Moreover, our results show that PCTAIRE1 is also degraded by BRCA1, a well-known tumor suppressor. Together, our studies highlight the regulation of PCTAIRE1 by key players of the major cell signaling pathways involved in regulating cell proliferation, and therefore, provide crucial links that could be explored further to elucidate the mechanistic role of PCTAIRE1 in cell proliferation and tumorigenesis.
Collapse
Affiliation(s)
| | - Misbah Un Nisa
- Department of Biochemistry, University of Kashmir, Srinagar 190006, India
| | - Zarka Sarwar
- Department of Biochemistry, University of Kashmir, Srinagar 190006, India
| | - Irfana Reshi
- Department of Biotechnology, University of Kashmir, Srinagar 190006, India
| | - Sameer Ahmed Bhat
- Department of Biotechnology, University of Kashmir, Srinagar 190006, India
| | - Nusrat Nabi
- Department of Biochemistry, University of Kashmir, Srinagar 190006, India
| | - Shaida Andrabi
- Department of Biochemistry, University of Kashmir, Srinagar 190006, India.
| |
Collapse
|
11
|
Zhu W, Liu Y, Zhang W, Fan W, Wang S, Gu JH, Sun H, Liu F. Selenomethionine protects hematopoietic stem/progenitor cells against cobalt nanoparticles by stimulating antioxidant actions and DNA repair functions. Aging (Albany NY) 2021; 13:11705-11726. [PMID: 33875618 PMCID: PMC8109066 DOI: 10.18632/aging.202865] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Accepted: 01/22/2021] [Indexed: 01/13/2023]
Abstract
Hematopoietic stem cells (HSCs) and hematopoietic progenitor cells (HPCs) can differentiate into all blood lineages to maintain hematopoiesis, wound healing, and immune functions. Recently, cobalt-chromium alloy casting implants have been used extensively in total hip replacements; however, cobalt nanoparticles (CoNPs) released from the alloy were toxic to HSCs and HPCs. We aimed to investigate the mechanism underlying the toxic effect of CoNPs on HSCs/HPCs and to determine the protective effect of selenomethionine (SeMet) against CoNPs in vitro and in vivo. Human and rat CD34+ HSCs/HPCs were isolated from cord blood and bone marrow, respectively. CoNPs decreased the viability of CD34+ HSCs/HPCs and increased apoptosis. SeMet attenuated the toxicity of CoNPs by enhancing the antioxidant ability of cells. The protective effect of SeMet was not completely abolished after adding H2O2 to abrogate the improvement of the antioxidant capacity by SeMet. SeMet and CoNPs stimulated ATM/ATR DNA damage response signals and inhibited cell proliferation. Unlike CoNPs, SeMet did not damage the DNA, and cell proliferation recovered after removing SeMet. SeMet inhibited the CoNP-induced upregulation of hypoxia inducible factor (HIF)-1α, thereby disrupting the inhibitory effect of HIF-1α on breast cancer type 1 susceptibility protein (BRCA1). Moreover, SeMet promoted BRCA1-mediated ubiquitination of cyclin B by upregulating UBE2K. Thus, SeMet enhanced cell cycle arrest and DNA repair post-CoNP exposure. Overall, SeMet protected CD34+ HSCs/HPCs against CoNPs by stimulating antioxidant activity and DNA repair.
Collapse
Affiliation(s)
- Wenfeng Zhu
- Orthopaedic Laboratory, Affiliated Hospital of Nantong University, Nantong, Jiangsu Province, China.,Department of Orthopaedics, The Sixth Affiliated Hospital of Nantong University, Yancheng, Jiangsu Province, China
| | - Yake Liu
- Department of Orthopaedics, Affiliated Hospital of Nantong University, Nantong, Jiangsu Province, China
| | - Weinan Zhang
- Orthopaedic Laboratory, Affiliated Hospital of Nantong University, Nantong, Jiangsu Province, China
| | - Wentao Fan
- Department of Orthopaedics, Affiliated Hospital of Nantong University, Nantong, Jiangsu Province, China
| | - Siqi Wang
- Orthopaedic Laboratory, Affiliated Hospital of Nantong University, Nantong, Jiangsu Province, China
| | - Jin-Hua Gu
- Department of Clinical Pharmacy, Affiliated Maternity and Child Health Care Hospital of Nantong University, Nantong, Jiangsu Province, China.,Department of Orthopaedics, The Sixth Affiliated Hospital of Nantong University, Yancheng, Jiangsu Province, China
| | - Huanjian Sun
- Department of Orthopaedics, The Sixth Affiliated Hospital of Nantong University, Yancheng, Jiangsu Province, China
| | - Fan Liu
- Department of Orthopaedics, Affiliated Hospital of Nantong University, Nantong, Jiangsu Province, China
| |
Collapse
|
12
|
Wang Q, Dong Z, Su J, Huang J, Xiao P, Tian L, Chen Y, Ma L, Chen X. Ixazomib inhibits myeloma cell proliferation by targeting UBE2K. Biochem Biophys Res Commun 2021; 549:1-7. [PMID: 33647537 DOI: 10.1016/j.bbrc.2021.02.048] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Accepted: 02/11/2021] [Indexed: 11/26/2022]
Abstract
PURPOSE Ixazomib is a selective, effective, and reversible inhibitor of 20S proteasome and is approved for the treatment of multiple myeloma. Ubiquitin-conjugating enzyme E2 (UBE2K) is involved in the synthesis of K48-linked ubiquitin chains and is the target of certain drugs used for the treatment of tumors. The purpose of this study was to investigate the relationship between ixazomib and UBE2K in myeloma cells. METHODS We used CCK-8 and Annexin V-FITC/propidium iodide kit to detect the effects of ixazomib on survival and apoptosis of RPMI-8226 and U-266 myeloma cell lines. Quantitative polymerase chain reaction and western blot were used to detect the change in gene and protein expression levels of myeloma cells treated with ixazomib. Furthermore, the regulatory effects of ixazomib on UBE2K and its downstream targets were investigated following the overexpression of UBE2K. RESULTS In myeloma cells, ixazomib decreased cell survival and increased apoptosis in a dose-dependent manner. Ixazomib significantly increased the expression of HIST1H2BD, MNAT1, NEK3, and TARS2, while decreasing the expression of HSPA1B and UBE2K. In addition, ixazomib inhibited the proliferation of myeloma cells, blocked cell cycle, induced cell apoptosis, and increased the production of reactive oxygen species by inhibiting UBE2K expression. Lastly, ixazomib regulates mitosis- and apoptosis-related genes by lowering UBE2K expression. CONCLUSION In summary, ixazomib leads to impaired proliferation of myeloma cells by targeting UBE2K.
Collapse
Affiliation(s)
- Qingqing Wang
- Blood Rheumatism Immunology Department, The Second Affiliated Hospital of Xiamen Medical College, Xiamen, Fujian, China.
| | - Zhigao Dong
- Blood Rheumatism Immunology Department, The Second Affiliated Hospital of Xiamen Medical College, Xiamen, Fujian, China.
| | - Junnan Su
- Blood Rheumatism Immunology Department, The Second Affiliated Hospital of Xiamen Medical College, Xiamen, Fujian, China.
| | - Jinmei Huang
- Blood Rheumatism Immunology Department, The Second Affiliated Hospital of Xiamen Medical College, Xiamen, Fujian, China.
| | - Pingping Xiao
- Blood Rheumatism Immunology Department, The Second Affiliated Hospital of Xiamen Medical College, Xiamen, Fujian, China.
| | - Lihong Tian
- Blood Rheumatism Immunology Department, The Second Affiliated Hospital of Xiamen Medical College, Xiamen, Fujian, China.
| | - Yongquan Chen
- Blood Rheumatism Immunology Department, The Second Affiliated Hospital of Xiamen Medical College, Xiamen, Fujian, China.
| | - Lili Ma
- Blood Rheumatism Immunology Department, The Second Affiliated Hospital of Xiamen Medical College, Xiamen, Fujian, China.
| | - Xuyan Chen
- Blood Rheumatism Immunology Department, The Second Affiliated Hospital of Xiamen Medical College, Xiamen, Fujian, China.
| |
Collapse
|
13
|
Nakamura M, Kaneko S, Dickson DW, Kusaka H. Aberrant Accumulation of BRCA1 in Alzheimer Disease and Other Tauopathies. J Neuropathol Exp Neurol 2020; 79:22-33. [PMID: 31750914 DOI: 10.1093/jnen/nlz107] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Revised: 08/22/2019] [Indexed: 12/17/2022] Open
Abstract
BRCA1 plays an important roles in several biological events during the DNA damage response (DDR). Recently, some reports have indicated that BRCA1 dysfunction is involved in the pathogenesis of Alzheimer disease (AD). Furthermore, it has also been reported that BRCA1 accumulates within neurofibrillary tangles (NFTs) in the AD brain. In this study, we examined the immunohistochemical distribution of BRCA1 and another DDR protein, p53-Binding Protein 1 (53BP1), in AD, Pick disease (PiD), progressive supranuclear palsy (PSP), corticobasal degeneration, and frontotemporal dementia with parkinsonism linked to chromosome 17. In control subjects, neither BRCA1 nor phosphorylated BRCA1 (pBRCA1; Ser1524) immunoreactivity was observed in neurons or glial cells; and that for pBRCA1 (Ser1423) and 53BP1 were slightly detected in neuronal nuclei. The immunoreactivity for both BRCA1 and pBRCA1 (Ser1423) was localized within phosphorylated tau inclusions in all tauopathies, whereas that for pBRCA1 (Ser1524) was mainly associated with Pick bodies in PiD and to a lesser extent with NFTs in AD. On the other hand, 53BP1-immunoreactive deposits tended to be increased in the nucleus of neurons in AD and PSP compared with those in control cases. Our results suggest that DDR dysfunction due to cytoplasmic sequestration of BRCA1 could be involved in the pathogenesis of tauopathies.
Collapse
Affiliation(s)
- Masataka Nakamura
- Department of Neurology, Kansai Medical University, Hirakata, Osaka, Japan (MN, SK, HK); and Department of Neuroscience, Mayo Clinic, Jacksonville, Florida (DWD)
| | - Satoshi Kaneko
- Department of Neurology, Kansai Medical University, Hirakata, Osaka, Japan (MN, SK, HK); and Department of Neuroscience, Mayo Clinic, Jacksonville, Florida (DWD)
| | - Dennis W Dickson
- Department of Neurology, Kansai Medical University, Hirakata, Osaka, Japan (MN, SK, HK); and Department of Neuroscience, Mayo Clinic, Jacksonville, Florida (DWD)
| | - Hirofumi Kusaka
- Department of Neurology, Kansai Medical University, Hirakata, Osaka, Japan (MN, SK, HK); and Department of Neuroscience, Mayo Clinic, Jacksonville, Florida (DWD)
| |
Collapse
|
14
|
Xiao G, Yang Q, Bao Z, Mao H, Zhang Y, Lin S. Expression of tripartite motif-containing 44 and its prognostic and clinicopathological value in human malignancies:a meta-analysis. BMC Cancer 2020; 20:525. [PMID: 32503466 PMCID: PMC7275359 DOI: 10.1186/s12885-020-07014-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Accepted: 05/28/2020] [Indexed: 01/29/2023] Open
Abstract
BACKGROUND Previous researches have reported that tripartite motif-containing 44 (TRIM44) is related to the prognosis of multiple human tumors. This study was designed to systematically assess the prognostic value of TRIM44 in human malignancies and summarize its possible tumor-related mechanisms. METHODS The available databases were searched for eligible studies that evaluated the clinicopathological and prognostic roles of TRIM44 in patients with malignancies. The hazard ratios (HR) and odds ratios (OR) were combined to assess the predictive role of TRIM44 using Stata/SE 14.1 software. RESULTS A total of 1740 patients from thirteen original studies were finally included in this study. The results of the combined analysis showed that over-expression of TRIM44 protein was significantly correlated with shorter overall survival (OS) (HR = 1.94, 95% CI: 1.60-2.35) and worse disease-free survival (DFS) (HR = 2.13, 95% CI: 1.24-3.65) in cancer patients. Additionally, the combined ORs indicated that elevated expression level of TRIM44 protein was significantly associated with lymph node metastasis (OR = 2.69, 95% CI: 1.71-4.24), distant metastasis (OR = 10.35, 95% CI: 1.01-106.24), poor tumor differentiation (OR = 1.78, 95% CI: 1.03-3.09), increased depth of tumor invasion (OR = 2.72, 95% CI: 1.73-4.30), advanced clinical stage (OR = 2.75, 95% CI: 2.04-3.71), and recurrence (OR = 2.30, 95% CI: 1.34-3.95). Furthermore, analysis results using Gene Expression Profiling Interactive Analysis (GEPIA) showed that the expression level of TRIM44 mRNA was higher in most tumor tissues than in the corresponding normal tissues, and the relationship between TRIM44 mRNA level and prognosis in various malignant tumors also explored in GEPIA and OS analysis webservers. CONCLUSIONS TRIM44 may serve as a valuable prognostic biomarker and a potential therapeutic target for patients with malignancies.
Collapse
Affiliation(s)
- Guoliang Xiao
- Department of General Surgery, the First People's Hospital of Neijiang, Neijiang, 641000, Sichuan Province, PR China
| | - Qiuxi Yang
- Department of Hepatobiliary Surgery, The First Affiliated Hospital of Hainan Medical University, Haikou, 570100, Hainan Province, PR China
| | - Ziwei Bao
- Department of medicine, Southwest Medical University, Luzhou, 646000, Sichuan Province, PR China
| | - Haixia Mao
- Department of medicine, Southwest Medical University, Luzhou, 646000, Sichuan Province, PR China
| | - Yi Zhang
- Department of General Surgery, the First People's Hospital of Neijiang, Neijiang, 641000, Sichuan Province, PR China.
| | - Shibu Lin
- Department of Hepatobiliary Surgery, The First Affiliated Hospital of Hainan Medical University, Haikou, 570100, Hainan Province, PR China
| |
Collapse
|
15
|
Ren D, Song J, Ni M, Kang L, Guo W. Regulatory Mechanisms of Cell Polyploidy in Insects. Front Cell Dev Biol 2020; 8:361. [PMID: 32548115 PMCID: PMC7272692 DOI: 10.3389/fcell.2020.00361] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2020] [Accepted: 04/22/2020] [Indexed: 12/14/2022] Open
Abstract
Polyploidy cells undergo the endocycle to generate DNA amplification without cell division and have important biological functions in growth, development, reproduction, immune response, nutrient support, and conferring resistance to DNA damage in animals. In this paper, we have specially summarized current research progresses in the regulatory mechanisms of cell polyploidy in insects. First, insect hormones including juvenile hormone and 20-hydroxyecdysone regulate the endocycle of variant cells in diverse insect species. Second, cells skip mitotic division in response to developmental programming and conditional stimuli such as wound healing, regeneration, and aging. Third, the reported regulatory pathways of mitotic to endocycle switch (MES), including Notch, Hippo, and JNK signaling pathways, are summarized and constructed into genetic network. Thus, we think that the studies in crosstalk of hormones and their effects on canonical pathways will shed light on the mechanism of cell polyploidy and elucidate the evolutionary adaptions of MES through diverse insect species.
Collapse
Affiliation(s)
- Dani Ren
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Juan Song
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, China
| | - Ming Ni
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,College of Life Sciences, Hebei University, Baoding, China
| | - Le Kang
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, China.,College of Life Sciences, Hebei University, Baoding, China
| | - Wei Guo
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, China
| |
Collapse
|
16
|
Cimmino F, Avitabile M, Lasorsa VA, Pezone L, Cardinale A, Montella A, Cantalupo S, Iolascon A, Capasso M. Functional characterization of full-length BARD1 strengthens its role as a tumor suppressor in neuroblastoma. J Cancer 2020; 11:1495-1504. [PMID: 32047556 PMCID: PMC6995383 DOI: 10.7150/jca.36164] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Accepted: 11/12/2019] [Indexed: 01/10/2023] Open
Abstract
BARD1 is associated with the development of high-risk neuroblastoma patients. Particularly, the expression of full length (FL) isoform, FL BARD1, correlates to high-risk neuroblastoma development and its inhibition is sufficient to induce neuroblastoma cells towards a worst phenotype. Here we have investigated the mechanisms of FL BARD1 in neuroblastoma cell lines depleted for FL BARD1 expression. We have shown that FL BARD1 expression protects the cells from spontaneous DNA damage and from damage accumulated after irradiation. We demonstrated a role for FL BARD1 as tumor suppressor to prevent unscheduled mitotic entry of DNA damaged cells and to lead to death cells that have bypassed cell cycle checkpoints. FL BARD1-depleted cells that have survived to checkpoints acquire features of aggressiveness. Overall, our results show that FL BARD1 may defend cells against cancer and prevent malignant transformation of cells.
Collapse
Affiliation(s)
- Flora Cimmino
- Dipartimento di Medicina Molecolare e Biotecnologie Mediche, Università degli Studi di Napoli “Federico II”, Naples, Italy
- CEINGE Biotecnologie Avanzate, Naples, Italy
| | - Marianna Avitabile
- Dipartimento di Medicina Molecolare e Biotecnologie Mediche, Università degli Studi di Napoli “Federico II”, Naples, Italy
- CEINGE Biotecnologie Avanzate, Naples, Italy
| | - Vito Alessandro Lasorsa
- Dipartimento di Medicina Molecolare e Biotecnologie Mediche, Università degli Studi di Napoli “Federico II”, Naples, Italy
- CEINGE Biotecnologie Avanzate, Naples, Italy
| | - Lucia Pezone
- Dipartimento di Medicina Molecolare e Biotecnologie Mediche, Università degli Studi di Napoli “Federico II”, Naples, Italy
| | - Antonella Cardinale
- Dipartimento di Medicina Molecolare e Biotecnologie Mediche, Università degli Studi di Napoli “Federico II”, Naples, Italy
| | | | | | - Achille Iolascon
- Dipartimento di Medicina Molecolare e Biotecnologie Mediche, Università degli Studi di Napoli “Federico II”, Naples, Italy
- CEINGE Biotecnologie Avanzate, Naples, Italy
| | - Mario Capasso
- Dipartimento di Medicina Molecolare e Biotecnologie Mediche, Università degli Studi di Napoli “Federico II”, Naples, Italy
- CEINGE Biotecnologie Avanzate, Naples, Italy
- IRCCS SDN, Naples, Italy
| |
Collapse
|
17
|
Rodriguez Sawicki L, Garcia KA, Corsico B, Scaglia N. De novo lipogenesis at the mitotic exit is used for nuclear envelope reassembly/expansion. Implications for combined chemotherapy. Cell Cycle 2019; 18:1646-1659. [PMID: 31203714 DOI: 10.1080/15384101.2019.1629792] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
Abstract
Mitosis has been traditionally considered a metabolically inactive phase. We have previously shown, however, that extensive alterations in lipids occur as the cells traverse mitosis, including increased de novo fatty acid (FA) and phosphatidylcholine (PtdCho) synthesis and decreased lysophospholipid content. Given the diverse structural and functional properties of these lipids, we sought to study their metabolic fate and their importance for cell cycle completion. Here we show that FA and PtdCho synthesized at the mitotic exit are destined to the nuclear envelope. Importantly, FA and PtdCho synthesis, but not the decrease in lysophospholipid content, are necessary for cell cycle completion beyond G2/M. Moreover, the presence of alternative pathways for PtdCho synthesis renders the cells less sensitive to its inhibition than to the impairment of FA synthesis. FA synthesis, thus, represents a cell cycle-related metabolic vulnerability that could be exploited for combined chemotherapy. We explored the combination of fatty acid synthase (FASN) inhibition with agents that act at different phases of the cell cycle. Our results show that the effect of FASN inhibition may be enhanced under some drug combinations.
Collapse
Affiliation(s)
- Luciana Rodriguez Sawicki
- a Instituto de Investigaciones Bioquímicas de La Plata (INIBOLP), UNLP/CONICET, Facultad de Ciencias Médicas , Universidad Nacional de La Plata , La Plata , Argentina
| | - Karina A Garcia
- a Instituto de Investigaciones Bioquímicas de La Plata (INIBOLP), UNLP/CONICET, Facultad de Ciencias Médicas , Universidad Nacional de La Plata , La Plata , Argentina
| | - Betina Corsico
- a Instituto de Investigaciones Bioquímicas de La Plata (INIBOLP), UNLP/CONICET, Facultad de Ciencias Médicas , Universidad Nacional de La Plata , La Plata , Argentina
| | - Natalia Scaglia
- a Instituto de Investigaciones Bioquímicas de La Plata (INIBOLP), UNLP/CONICET, Facultad de Ciencias Médicas , Universidad Nacional de La Plata , La Plata , Argentina
| |
Collapse
|
18
|
A Multidimensional Characterization of E3 Ubiquitin Ligase and Substrate Interaction Network. iScience 2019; 16:177-191. [PMID: 31181401 PMCID: PMC6557761 DOI: 10.1016/j.isci.2019.05.033] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2017] [Revised: 04/14/2019] [Accepted: 05/22/2019] [Indexed: 12/22/2022] Open
Abstract
E3 ubiquitin ligases (E3s) play a critical role in molecular and cellular mechanisms. However, a large number of E3-substrate interactions (ESIs) remain unrevealed. Here, we integrated the increasing omics data with biological knowledge to characterize and identify ESIs. Multidimensional features were computed to obtain the association patterns of ESIs, and an ensemble prediction model was constructed to identify ESIs. Comparison with non-ESI cases revealed the specific association patterns of ESIs, which provided meaningful insights into ESI interpretation. Reliability of the prediction model was confirmed from various perspectives. Notably, our evaluations on leucine-rich repeat family of F box (FBXL) family were consistent with a proteomic study, and several substrates for SKP2 and an orphan E3 FBXL6 were experimentally verified. Moreover, a cancer hallmark ESI landscape was studied. Taken together, our study catches a glimpse at the omics-driven ESI association patterns and provides a valuable resource (http://www.esinet.dicp.ac.cn/home.php) to assist ubiquitination research. Systematically describe E3 ligase and substrate association patterns Build a computational model for predicting E3 ligase and substrate interactions Predict and validate promising substrates for F box family E3 ligases Construct a valuable data resource on potential E3-substrate interactions
Collapse
|
19
|
Gorodetska I, Kozeretska I, Dubrovska A. BRCA Genes: The Role in Genome Stability, Cancer Stemness and Therapy Resistance. J Cancer 2019; 10:2109-2127. [PMID: 31205572 PMCID: PMC6548160 DOI: 10.7150/jca.30410] [Citation(s) in RCA: 108] [Impact Index Per Article: 21.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2018] [Accepted: 02/20/2019] [Indexed: 12/14/2022] Open
Abstract
Carcinogenesis is a multistep process, and tumors frequently harbor multiple mutations regulating genome integrity, cell division and death. The integrity of cellular genome is closely controlled by the mechanisms of DNA damage signaling and DNA repair. The association of breast cancer susceptibility genes BRCA1 and BRCA2 with breast and ovarian cancer development was first demonstrated over 20 years ago. Since then the germline mutations within these genes were linked to genomic instability and increased risk of many other cancer types. Genomic instability is an engine of the oncogenic transformation of non-tumorigenic cells into tumor-initiating cells and further tumor evolution. In this review we discuss the biological functions of BRCA1 and BRCA2 genes and the role of BRCA mutations in tumor initiation, regulation of cancer stemness, therapy resistance and tumor progression.
Collapse
Affiliation(s)
- Ielizaveta Gorodetska
- OncoRay-National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden and Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany
| | - Iryna Kozeretska
- Department of General and Medical Genetics, ESC "The Institute of Biology and Medicine", Taras Shevchenko National University of Kyiv, Kyiv, Ukraine
| | - Anna Dubrovska
- OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Germany; Helmholtz-Zentrum Dresden - Rossendorf, Institute of Radiooncology - OncoRay, Dresden, Germany; German Cancer Consortium (DKTK), Partner site Dresden, Germany; German Cancer Research Center (DKFZ), Heidelberg, Germany
| |
Collapse
|
20
|
MiR-210-3p protects endometriotic cells from oxidative stress-induced cell cycle arrest by targeting BARD1. Cell Death Dis 2019; 10:144. [PMID: 30760709 PMCID: PMC6374490 DOI: 10.1038/s41419-019-1395-6] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Revised: 01/07/2019] [Accepted: 01/21/2019] [Indexed: 01/24/2023]
Abstract
Endometriosis is associated with benign but adversely developed cysts in the extrauterine environment. The oxidative imbalanced environment induces DNA damage and affects cell cycle progression of endometrial stromal cells (ESCs) and endometrial epithelial cells, but how endometriotic cells maintain proliferation in the presence of oxidative stress is not clear. Growing evidence has indicated that the ectopic hypoxic microenvironment and oxidative stress can stimulate the growth of endometriotic cells, which is mainly due to the increase of HIF-1α. We found that the master hypoxia-associated miRNA miR-210-3p was increased in stromal and glandular cells of ectopic lesions compared with that of eutopic and normal endometria and was consistent with the expression of HIF-1α and the local oxidative stress-induced DNA damage predictor 8-OHdG. Moreover, miR-210-3p was upregulated in ESCs and Ishikawa cells under hypoxic conditions but not in normoxic culture. Knockdown of miR-210-3p induced a G2/M arrest of ESCs and Ishikawa cells under hypoxia, while no effect was found under normoxia. BARD1 was identified as a target of miR-210-3p. BARD1 expression was decreased in endometriotic tissues compared with eutopic and normal endometria and negatively correlated with the expression of miR-210-3p. Multivariate regression analysis showed that BARD1 downregulation could serve as an indicator for endometriotic severity. Our results suggest that miR-210-3p attenuates the G2/M cell cycle checkpoint by inactivating BRCA1 complex function in response to DNA damage under hypoxia via targeting the 3′ untranslated region of BARD1 mRNA. Endometriotic mouse model experiments showed that intraperitoneal injection of the miR-210-3p inhibitor or vitamin C suppressed the growth of endometriotic lesions. Together, our results demonstrate that endometriotic cells inhibit BARD1/BRCA1 function by upregulating miR-210-3p, which might be the underlying mechanism for endometriotic cell maintenance of growth in oxidative stress. Furthermore, inhibition of miR-210-3p and administration of vitamin C are promising approaches for the treatment of endometriosis.
Collapse
|
21
|
Simhadri S, Vincelli G, Huo Y, Misenko S, Foo TK, Ahlskog J, Sørensen CS, Oakley GG, Ganesan S, Bunting SF, Xia B. PALB2 connects BRCA1 and BRCA2 in the G2/M checkpoint response. Oncogene 2018; 38:1585-1596. [PMID: 30337689 PMCID: PMC6408219 DOI: 10.1038/s41388-018-0535-2] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2018] [Revised: 08/13/2018] [Accepted: 09/21/2018] [Indexed: 01/07/2023]
Abstract
The G2/M checkpoint inhibits mitotic entry upon DNA damage thereby preventing segregation of broken chromosomes and preserving genome stability. The tumor suppressor proteins BRCA1, PALB2 and BRCA2 constitute a BRCA1-PALB2-BRCA2 axis that is essential for homologous recombination (HR)-based DNA double strand break repair. Besides HR, BRCA1 has been implicated in both the initial activation and the maintenance of the G2/M checkpoint, while BRCA2 and PALB2 have been shown to be critical for its maintenance. Here we show that all 3 proteins can play a significant role in both checkpoint activation and checkpoint maintenance, depending on cell type and context, and that PALB2 links BRCA1 and BRCA2 in checkpoint response. The BRCA1-PALB2 interaction can be important for checkpoint activation, whereas the PALB2-BRCA2 complex formation appears to be more critical for checkpoint maintenance. Interestingly, the function of PALB2 in checkpoint response appears to be independent of CHK1 and CHK2 phosphorylation. Following ionizing radiation, cells with disengaged BRCA1-PALB2 interaction show greatly increased chromosomal abnormalities due apparently to combined defects in HR and checkpoint control. These findings provide new insights into DNA damage checkpoint control and further underscore the critical importance of the proper cooperation of the BRCA and PALB2 proteins in genome maintenance.
Collapse
Affiliation(s)
- Srilatha Simhadri
- Rutgers Cancer Institute of New Jersey, New Brunswick, USA.,Department of Radiation Oncology, Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ, 08903, USA.,Department of Medicine, Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ, 08903, USA
| | - Gabriele Vincelli
- Rutgers Cancer Institute of New Jersey, New Brunswick, USA.,Department of Radiation Oncology, Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ, 08903, USA
| | - Yanying Huo
- Rutgers Cancer Institute of New Jersey, New Brunswick, USA.,Department of Radiation Oncology, Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ, 08903, USA
| | - Sarah Misenko
- Department of Molecular Biology and Biochemistry, School of Arts and Sciences, Rutgers, The State University of New Jersey, Piscataway, NJ, 08854, USA
| | - Tzeh Keong Foo
- Rutgers Cancer Institute of New Jersey, New Brunswick, USA.,Department of Radiation Oncology, Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ, 08903, USA
| | - Johanna Ahlskog
- Biotech Research and Innovation Centre (BRIC), University of Copenhagen, Copenhagen, Denmark
| | - Claus S Sørensen
- Biotech Research and Innovation Centre (BRIC), University of Copenhagen, Copenhagen, Denmark
| | - Gregory G Oakley
- Department of Oral Biology, College of Dentistry, University of Nebraska Medical Center, Lincoln, NE, 68583, USA
| | - Shridar Ganesan
- Rutgers Cancer Institute of New Jersey, New Brunswick, USA.,Department of Medicine, Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ, 08903, USA
| | - Samuel F Bunting
- Department of Molecular Biology and Biochemistry, School of Arts and Sciences, Rutgers, The State University of New Jersey, Piscataway, NJ, 08854, USA
| | - Bing Xia
- Rutgers Cancer Institute of New Jersey, New Brunswick, USA. .,Department of Radiation Oncology, Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ, 08903, USA.
| |
Collapse
|
22
|
Choi EK, Lim JA, Kim JK, Jang MS, Kim SE, Baek HJ, Park EJ, Kim TH, Deng CX, Wang RH, Kim SS. Cyclin B1 stability is increased by interaction with BRCA1, and its overexpression suppresses the progression of BRCA1-associated mammary tumors. Exp Mol Med 2018; 50:1-16. [PMID: 30327455 PMCID: PMC6191436 DOI: 10.1038/s12276-018-0169-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Revised: 09/09/2018] [Accepted: 09/11/2018] [Indexed: 12/29/2022] Open
Abstract
Germline BRCA1 mutations predispose women to breast and ovarian cancer. BRCA1, a large protein with multiple functional domains, interacts with numerous proteins involved in many important biological processes and pathways. However, to date, the role of BRCA1 interactions at specific stages in the progression of mammary tumors, particularly in relation to cell cycle regulation, remains elusive. Here, we demonstrate that BRCA1 interacts with cyclin B1, a crucial cell cycle regulator, and that their interaction is modulated by DNA damage and cell cycle phase. In DNA-damaged mitotic cells, BRCA1 inhibits cytoplasmic transportation of cyclin B1, which prevents cyclin B1 degradation. Moreover, restoration of cyclin B1 in BRCA1-deficient cells reduced cell survival in association with induction of apoptosis. We further demonstrate that treatment of Brca1-mutant mammary tumors with vinblastine, which induces cyclin B1, significantly reduced tumor progression. In addition, a correlation analysis of vinblastine responses and gene expression profiles in tumors at baseline revealed 113 genes that were differentially expressed between tumors that did and did not respond to vinblastine treatment. Further analyses of protein–protein interaction networks revealed gene clusters related to vinblastine resistance, including nucleotide excision repair, epigenetic regulation, and the messenger RNA surveillance pathway. These findings enhance our understanding of how loss of BRCA1 disrupts mitosis regulation through dysregulation of cyclin B1 and provide evidence suggesting that targeting cyclin B1 may be useful in BRCA1-associated breast cancer therapy. The role of disrupted activity of the protein BRCA1 in the progression of breast cancer has been clarified, suggesting that targeting another protein with which it interacts could offer a new route to treatment. Mutations of BRCA1 are known to predispose women to both breast and ovarian cancers. Researchers led by Sang Soo Kim (National Cancer Center, South Korea) and Rui-Hong Wang (University of Macau, China) studied the interaction with a protein called cyclin B1 that controls cell growth and division. They found that, in mitosis, BRCA1 interacts with and stabilizes cyclin B1, explaining why the loss of BRCA1 can disrupt the G2/M cell cycle control and accumulate the genetic instability. Treatment of Brca1-mutant mammary tumors with vinblastine, which alters cyclin B1 level, significantly reduced tumor progression with reduction of survival and induction of apoptosis.
Collapse
Affiliation(s)
- Eun Kyung Choi
- Research Institute, National Cancer Center, Goyang, 10408, Korea
| | - Jeong-A Lim
- Research Institute, National Cancer Center, Goyang, 10408, Korea
| | - Jong Kwang Kim
- Research Institute, National Cancer Center, Goyang, 10408, Korea
| | - Moon Sun Jang
- Research Institute, National Cancer Center, Goyang, 10408, Korea
| | - Sun Eui Kim
- Research Institute, National Cancer Center, Goyang, 10408, Korea
| | - Hye Jung Baek
- Research Institute, National Cancer Center, Goyang, 10408, Korea
| | - Eun Jung Park
- Research Institute, National Cancer Center, Goyang, 10408, Korea
| | - Tae Hyun Kim
- Research Institute, National Cancer Center, Goyang, 10408, Korea
| | - Chu-Xia Deng
- Cancer Centre, Faculty of Health Sciences, University of Macau, Macau, 999078, China
| | - Rui-Hong Wang
- Cancer Centre, Faculty of Health Sciences, University of Macau, Macau, 999078, China.
| | - Sang Soo Kim
- Research Institute, National Cancer Center, Goyang, 10408, Korea.
| |
Collapse
|
23
|
Cai M, Zhang H, Hou L, Gao W, Song Y, Cui X, Li C, Guan R, Ma J, Wang X, Han Y, Lv Y, Chen F, Wang P, Meng X, Fu S. Inhibiting homologous recombination decreases extrachromosomal amplification but has no effect on intrachromosomal amplification in methotrexate-resistant colon cancer cells. Int J Cancer 2018; 144:1037-1048. [PMID: 30070702 PMCID: PMC6586039 DOI: 10.1002/ijc.31781] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Revised: 02/23/2018] [Accepted: 07/24/2018] [Indexed: 01/08/2023]
Abstract
Gene amplification, which involves the two major topographical structures double minutes (DMs) and homegeneously stained region (HSR), is a common mechanism of treatment resistance in cancer and is initiated by DNA double‐strand breaks. NHEJ, one of DSB repair pathways, is involved in gene amplification as we demonstrated previously. However, the involvement of homologous recombination, another DSB repair pathway, in gene amplification remains to be explored. To better understand the association between HR and gene amplification, we detected HR activity in DM‐ and HSR‐containing MTX‐resistant HT‐29 colon cancer cells. In DM‐containing MTX‐resistant cells, we found increased homologous recombination activity compared with that in MTX‐sensitive cells. Therefore, we suppressed HR activity by silencing BRCA1, the key player in the HR pathway. The attenuation of HR activity decreased the numbers of DMs and DM‐form amplified gene copies and increased the exclusion of micronuclei and nuclear buds that contained DM‐form amplification; these changes were accompanied by cell cycle acceleration and increased MTX sensitivity. In contrast, BRCA1 silencing did not influence the number of amplified genes and MTX sensitivity in HSR‐containing MTX‐resistant cells. In conclusion, our results suggest that the HR pathway plays different roles in extrachromosomal and intrachromosomal gene amplification and may be a new target to improve chemotherapeutic outcome by decreasing extrachromosomal amplification in cancer. What's new? Double‐strand DNA breaks (DSBs) initiate gene amplification, a phenomenon associated with therapeutic resistance in cancer that involves two topographical structures, double minutes (DMs) and homogeneously staining regions (HSRs). Whether DSB repair pathways, particularly homologous recombination (HR), also influence gene amplification is unknown. Here, in methotrexate‐resistant colon cancer cells, HR inhibition effectively reduced gene amplification, specifically the DM‐form, by blocking DM formation and promoting DM exclusion via micronuclei. HR inhibition had no influence on the HSR‐form of gene amplification. Loss of gene amplification by HR inhibition, through partial reversal of methotrexate resistance, may contribute to improved chemotherapeutic outcome.
Collapse
Affiliation(s)
- Mengdi Cai
- Laboratory of Medical Genetics, Harbin Medical University, Harbin, 150081, China
| | - Huishu Zhang
- Laboratory of Medical Genetics, Harbin Medical University, Harbin, 150081, China
| | - Liqing Hou
- Department of Genetics, Inner Mongolia Maternal and Child Care Hospital, Hohhot, Inner Mongolia Autonomous Region, China
| | - Wei Gao
- Laboratory of Medical Genetics, Harbin Medical University, Harbin, 150081, China
| | - Ying Song
- Laboratory of Medical Genetics, Harbin Medical University, Harbin, 150081, China
| | - Xiaobo Cui
- Laboratory of Medical Genetics, Harbin Medical University, Harbin, 150081, China
| | - Chunxiang Li
- Laboratory of Medical Genetics, Harbin Medical University, Harbin, 150081, China
| | - Rongwei Guan
- Laboratory of Medical Genetics, Harbin Medical University, Harbin, 150081, China
| | - Jinfa Ma
- Laboratory of Medical Genetics, Harbin Medical University, Harbin, 150081, China
| | - Xu Wang
- Laboratory of Medical Genetics, Harbin Medical University, Harbin, 150081, China
| | - Yue Han
- Laboratory of Medical Genetics, Harbin Medical University, Harbin, 150081, China
| | - Yafan Lv
- Laboratory of Medical Genetics, Harbin Medical University, Harbin, 150081, China
| | - Feng Chen
- Laboratory of Medical Genetics, Harbin Medical University, Harbin, 150081, China
| | - Ping Wang
- Laboratory of Medical Genetics, Harbin Medical University, Harbin, 150081, China
| | - Xiangning Meng
- Laboratory of Medical Genetics, Harbin Medical University, Harbin, 150081, China
| | - Songbin Fu
- Laboratory of Medical Genetics, Harbin Medical University, Harbin, 150081, China
| |
Collapse
|
24
|
Kim S, Jin H, Seo HR, Lee HJ, Lee YS. Regulating BRCA1 protein stability by cathepsin S-mediated ubiquitin degradation. Cell Death Differ 2018; 26:812-825. [PMID: 30006610 PMCID: PMC6461859 DOI: 10.1038/s41418-018-0153-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2017] [Revised: 05/25/2018] [Accepted: 06/08/2018] [Indexed: 01/21/2023] Open
Abstract
Cathepsin S (CTSS) is a cysteine protease that is thought to play a role in many physiological and pathological processes including tumor growth, angiogenesis, and metastasis; it has been identified as a radiation response gene. Here, we examined the role of CTSS in regulating the DNA damage response in breast cancer cells. Activating CTSS (producing the cleavage form of the protein) by radiation induced proteolytic degradation of BRCA1, which ultimately suppressed DNA double-strand break repair activity. Depletion of CTSS by RNAi or expression of a mutant type of CTSS enhanced the protein stability of BRCA1 by inhibiting its ubiquitination. CTSS interacted with the BRCT domain of BRCA1 and facilitated ubiquitin-mediated proteolytic degradation of BRCA1, which was tightly associated with decreased BRCA1-mediated DNA repair activity. Treatment with a pharmacological CTSS inhibitor inhibited proteolytic degradation of BRCA1 and restored BRCA1 function. Depletion of CTSS by shRNA delayed tumor growth in a xenograft mouse model, only in the presence of functional BRCA1. Spontaneously uced rat mammary tumors and human breast cancer tissues with high levels of CTSS expression showed low BRCA1 expression. From these data, we suggest that CTSS inhibition is a good strategy for functional restoration of BRCA1 in breast cancers with reduced BRCA1 protein stability.
Collapse
Affiliation(s)
- SeoYoung Kim
- Graduate School of Pharmaceutical Sciences, Ewha Womans University, Seoul, 120-750, Korea
| | - Hee Jin
- Graduate School of Pharmaceutical Sciences, Ewha Womans University, Seoul, 120-750, Korea
| | - Hang-Rhan Seo
- Functional Morphometry II, Institute Pasteur Korea, Bundang-gu, Seongnam-si, Gyeonggi-do, 463-400, Korea
| | - Hae June Lee
- Division of Basic Radiation Bioscience, Korea Institute of Radiological and Medical Sciences, Seoul, 139-706, Korea
| | - Yun-Sil Lee
- Graduate School of Pharmaceutical Sciences, Ewha Womans University, Seoul, 120-750, Korea.
| |
Collapse
|
25
|
Abstract
Ubiquitin-conjugating enzymes (E2 enzymes) such as UBE2T target proteins for degradation via the proteasome. Here, we examined the effects of UBE2T on the progression of gastric cancer. UBE2T was highly expressed in gastric tumors and gastric cancer cells. siRNA-mediated suppression of UBE2T inhibited gastric cancer cell proliferation and colony formation by promoting cell cycle arrest at G2/M phase and increasing apoptosis. Suppression of UBE2T also attenuated the invasive and metastatic abilities of gastric cancer cells by altering expression of epithelial-mesenchymal transition (EMT)-related factors. A xenograft model in which nude mice were injected with UBE2T knockdown human gastric cancer cells confirmed that suppression of UBE2T also decreased tumor formation and growth in vivo. Expression levels of CCND1, Phospho-GSK3B, WNT family members, and MYC were all affected by UBE2T knockdown. These results suggest that UBE2T plays a critical role in gastric cancer, and that it may serve as a useful prognostic biomarker and therapeutic target in gastric cancer patients.
Collapse
|
26
|
Cong B, Ohsawa S, Igaki T. JNK and Yorkie drive tumor progression by generating polyploid giant cells in Drosophila. Oncogene 2018. [DOI: 10.1038/s41388-018-0201-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
|
27
|
Chen H, Han L, Tsai H, Wang Z, Wu Y, Duo Y, Cao W, Chen L, Tan Z, Xu N, Huang X, Zhuang J, Huang L. PICT-1 is a key nucleolar sensor in DNA damage response signaling that regulates apoptosis through the RPL11-MDM2-p53 pathway. Oncotarget 2018; 7:83241-83257. [PMID: 27829214 PMCID: PMC5347766 DOI: 10.18632/oncotarget.13082] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Accepted: 10/19/2016] [Indexed: 12/12/2022] Open
Abstract
PICT-1 is an essential ribosome biogenesis factor whose loss induces p53 accumulation and apoptosis. Here, we show that DNA damage changes PICT-1 localization and decreases PICT-1 protein levels via the proteasome pathway. Two important phosphatidylinositol 3-kinase-like kinases (PIKKs), ataxia-telangiectasia mutated (ATM) and the Ku70 subunit of DNA-dependent protein kinase (DNA-PK), co-localize and interact with PICT-1 in the nucleolus. Computational prediction of phosphorylation sites and detection using an anti-phospho-substrate antibody suggest that PICT-1 might be a substrate of PIKKs. PICT-1 S233 and T289 were identified as the key phosphorylation sites in this pathway, as mutating both to alanine abolished UVB-induced increase of PICT-1 phosporylation. Inhibition of PIKKs or ATM (with wortmannin and KU55933, respectively) prevented the agglomeration and degradation of PICT-1, suggesting that ATM is a key regulator of PICT-1. PICT-1(S233A, T289A) demonstrated marked resistance to DNA damage-induced agglomeration and loss of PICT-1. Phosphomimetic PICT-1 (S233D, T289D) showed a different nuclear distribution and was more rapidly degraded after DNA damage than wild-type PICT-1. Furthermore, both phosphorylation and degradation of PICT-1 released RPL11 from the nucleolus to the nucleoplasm, increased binding of RPL11 to MDM2, and promoted p53 accumulation and apoptosis in an ATM-dependent manner after DNA damage. These data indicate that PICT-1 is a major nucleolar sensor of the DNA damage repair response and an important upstream regulator of p53 via the RPL11-MDM2-p53 pathway.
Collapse
Affiliation(s)
- Hongbo Chen
- The Shenzhen Key Lab of Gene and Antibody Therapy, Center for Biotechnology & Biomedicine, Division of Life and Health Sciences, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, China.,School of Life Sciences, Tsinghua University, Beijing 100084, China.,Department of Biochemistry, McGill University, Montreal, QC H3G 1Y6, Canada
| | - Liqiao Han
- Department of Laboratory Science, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou 510120, China.,The Shenzhen Key Lab of Gene and Antibody Therapy, Center for Biotechnology & Biomedicine, Division of Life and Health Sciences, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, China
| | - Hsiangi Tsai
- The Shenzhen Key Lab of Gene and Antibody Therapy, Center for Biotechnology & Biomedicine, Division of Life and Health Sciences, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, China.,School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Zhiwei Wang
- Department of Laboratory Medicine, The Fourth Affiliated Hospital of Guangzhou Medical University, Guangzhou 511447, China
| | - Yanping Wu
- The Shenzhen Key Lab of Gene and Antibody Therapy, Center for Biotechnology & Biomedicine, Division of Life and Health Sciences, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, China.,School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Yanhong Duo
- The Shenzhen Key Lab of Gene and Antibody Therapy, Center for Biotechnology & Biomedicine, Division of Life and Health Sciences, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, China
| | - Wei Cao
- The Shenzhen Key Lab of Gene and Antibody Therapy, Center for Biotechnology & Biomedicine, Division of Life and Health Sciences, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, China.,School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Lijun Chen
- Technology Center of Guangxi Entry-Exit Inspection and Quarantine Bureau, Nanning 530021, China
| | - Zhirong Tan
- Department of Laboratory Science, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou 510120, China
| | - Ning Xu
- Department of Laboratory Science, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou 510120, China
| | - Xianzhang Huang
- Department of Laboratory Science, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou 510120, China
| | - Junhua Zhuang
- Department of Laboratory Science, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou 510120, China
| | - Laiqiang Huang
- The Shenzhen Key Lab of Gene and Antibody Therapy, Center for Biotechnology & Biomedicine, Division of Life and Health Sciences, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, China.,School of Life Sciences, Tsinghua University, Beijing 100084, China
| |
Collapse
|
28
|
Vázquez-Arreguín K, Maddox J, Kang J, Park D, Cano RR, Factor RE, Ludwig T, Tantin D. BRCA1 through Its E3 Ligase Activity Regulates the Transcription Factor Oct1 and Carbohydrate Metabolism. Mol Cancer Res 2018; 16:439-452. [PMID: 29330289 DOI: 10.1158/1541-7786.mcr-17-0364] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Revised: 10/17/2017] [Accepted: 11/10/2017] [Indexed: 12/19/2022]
Abstract
The tumor suppressor BRCA1 regulates the DNA damage response (DDR) and other processes that remain incompletely defined. Among these, BRCA1 heterodimerizes with BARD1 to ubiquitylate targets via its N-terminal E3 ligase activity. Here, it is demonstrated that BRCA1 promotes oxidative metabolism by degrading Oct1 (POU2F1), a transcription factor with proglycolytic and tumorigenic effects. BRCA1 E3 ubiquitin ligase mutation skews cells toward a glycolytic metabolic profile while elevating Oct1 protein. CRISPR-mediated Oct1 deletion reverts the glycolytic phenotype. RNA sequencing (RNAseq) confirms deregulation of metabolic genes downstream of Oct1. BRCA1 mediates Oct1 ubiquitylation and degradation, and mutation of two ubiquitylated Oct1 lysines insulates the protein against BRCA1-mediated destabilization. Oct1 deletion in MCF-7 breast cancer cells does not perturb growth in standard culture, but inhibits growth in soft agar and xenograft assays. In primary breast cancer clinical specimens, Oct1 protein levels correlate positively with tumor aggressiveness and inversely with BRCA1. These results identify BRCA1 as an Oct1 ubiquitin ligase that catalyzes Oct1 degradation to promote oxidative metabolism and restrict tumorigenicity. Mol Cancer Res; 16(3); 439-52. ©2018 AACR.
Collapse
Affiliation(s)
- Karina Vázquez-Arreguín
- Department of Pathology and Huntsman Cancer Institute, University of Utah School of Medicine, Salt Lake City, Utah
| | - Jessica Maddox
- Department of Pathology and Huntsman Cancer Institute, University of Utah School of Medicine, Salt Lake City, Utah
| | - Jinsuk Kang
- Department of Pathology and Huntsman Cancer Institute, University of Utah School of Medicine, Salt Lake City, Utah
| | - Dongju Park
- Department of Cancer Biology and Genetics, Comprehensive Cancer Center, Ohio State University, Columbus, Ohio
| | - Reuben R Cano
- Department of Pathology and Huntsman Cancer Institute, University of Utah School of Medicine, Salt Lake City, Utah
| | - Rachel E Factor
- Department of Pathology and Huntsman Cancer Institute, University of Utah School of Medicine, Salt Lake City, Utah
| | - Thomas Ludwig
- Department of Cancer Biology and Genetics, Comprehensive Cancer Center, Ohio State University, Columbus, Ohio
| | - Dean Tantin
- Department of Pathology and Huntsman Cancer Institute, University of Utah School of Medicine, Salt Lake City, Utah.
| |
Collapse
|
29
|
Tao L, Cao Y, Wei Z, Jia Q, Yu S, Zhong J, Wang A, Woodgett JR, Lu Y. Xanthatin triggers Chk1-mediated DNA damage response and destabilizes Cdc25C via lysosomal degradation in lung cancer cells. Toxicol Appl Pharmacol 2017; 337:85-94. [PMID: 29074359 DOI: 10.1016/j.taap.2017.10.015] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Revised: 10/01/2017] [Accepted: 10/17/2017] [Indexed: 12/21/2022]
Abstract
Previous studies had shown that xanthatin, a natural xanthanolide sesquiterpene lactone, could induce mitotic arrest and apoptosis in non-small cell lung cancer (NSCLC) cells. Here, we examined whether the DNA damage response (DDR) could be a primary cytotoxic event underlying xanthatin-mediated anti-tumor activity. Using EdU incorporation assay in combination with novel imaging flow cytometry, our data indicated that xanthatin suppressed DNA replication, prevented cells from G2/M entry and increased the spot count of γH2AX nuclear foci. Given that checkpoint kinase 1 (Chk1) represents a core component in DDR-mediated cell cycle transition and the phosphorylation on Ser-345 is essential for kinase activation and function, we surprisingly found xanthatin distinctly modulated Ser-345 phosphorylation of Chk1 in A549 and H1299 cells. Further investigation on Cdc25C/CDK1/CyclinB1 signaling cascade in the absence or presence of pharmacological DDR inhibitors showed that xanthatin directly destabilized the protein levels of Cdc25C, and recovery of p53 expression in p53-deficient H1299 cells further intensified xanthatin-mediated inhibition of Cdc25C, suggesting p53-dependent regulation of Cdc25C in a DDR machinery. Moreover, exogenous expression of Cdc25C was also substantially repressed by xanthatin and partially impaired xanthatin-induced G2 arrest. In addition, xanthatin could induce accumulation of ubiquitinated Cdc25C without undergoing further proteasomal degradation. However, an alternative lysosomal proteolysis of Cdc25C was observed. Interestingly, lysosome-like vesicles were produced upon xanthatin treatment, accompanied by rapid accumulation of lysosomal associated membrane protein LAPM-1. Furthermore, vacuolar proton (V)-ATPases inhibitor bafilomycin A1 and lysosomal proteases inhibitor leupeptin could remarkably overturn the levels of Cdc25C in xanthatin-treated H1299 cells. Altogether, these data provide insight into how xanthatin can be effectively targeted DDR molecules towards certain tumors.
Collapse
Affiliation(s)
- Li Tao
- Department of Pharmacy, College of Medicine, Yangzhou University, Yangzhou, Jiangsu 225001, China
| | - Yuzhu Cao
- Jiangsu Key Laboratory for Pharmacology and Safety Evaluation of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing, Jiangsu 210023, China
| | - Zhonghong Wei
- Jiangsu Key Laboratory for Pharmacology and Safety Evaluation of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing, Jiangsu 210023, China
| | - Qi Jia
- Jiangsu Key Laboratory for Pharmacology and Safety Evaluation of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing, Jiangsu 210023, China
| | - Suyun Yu
- Jiangsu Key Laboratory for Pharmacology and Safety Evaluation of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing, Jiangsu 210023, China
| | - Jinqiu Zhong
- Jiangsu Key Laboratory for Pharmacology and Safety Evaluation of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing, Jiangsu 210023, China
| | - Ainyun Wang
- Jiangsu Key Laboratory for Pharmacology and Safety Evaluation of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing, Jiangsu 210023, China
| | - James R Woodgett
- Lunenfeld-Tanenbaum Research Institute, Sinai Health System, Toronto, Ontario M5G 1X5, Canada; Department of Medical Biophysics, University of Toronto, Toronto, Ontario M5G 1X5, Canada.
| | - Yin Lu
- Jiangsu Key Laboratory for Pharmacology and Safety Evaluation of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing, Jiangsu 210023, China.
| |
Collapse
|
30
|
Croglio MP, Haake JM, Ryan CP, Wang VS, Lapier J, Schlarbaum JP, Dayani Y, Artuso E, Prandi C, Koltai H, Agama K, Pommier Y, Chen Y, Tricoli L, LaRocque JR, Albanese C, Yarden RI. Analogs of the novel phytohormone, strigolactone, trigger apoptosis and synergize with PARP inhibitors by inducing DNA damage and inhibiting DNA repair. Oncotarget 2017; 7:13984-4001. [PMID: 26910887 PMCID: PMC4924693 DOI: 10.18632/oncotarget.7414] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2015] [Accepted: 01/16/2016] [Indexed: 12/28/2022] Open
Abstract
Strigolactones are a novel class of plant hormones produced in roots that regulate shoot and root development. We previously reported that strigolactone analogs (SLs) induce G2/M cell cycle arrest and apoptosis in a variety of human cancer cells and inhibit tumor growth of human breast cancer xenografts in mice. SLs had no significant influences on non-transformed cells. Here we report for the first time that SLs induce DNA damage in the form of DNA double-strand breaks (DSBs) and activate the DNA damage response signaling by inducing phosphorylation of ATM, ATR and DNA-PKcs and co-localization of the DNA damage signaling protein, 53BP1, with γH2AX nuclear foci. We further report that in addition to DSBs induction, SLs simultaneously impair DSBs repair, mostly homology-directed repair (HDR) and to a lesser extent non-homologous end joining (NHEJ). In response to SLs, RAD51, the homologous DSB repair protein, is ubiquitinated and targeted for proteasomal degradation and it fails to co-localize with γH2AX foci. Interestingly, SLs synergize with DNA damaging agents-based therapeutics. The combination of PARP inhibitors and SLs showed an especially potent synergy, but only in BRCA1-proficient cells. No synergy was observed between SLs and PARP inhibitors in BRCA1-deficient cells, supporting a role for SLs in HDR impairment. Together, our data suggest that SLs increase genome instability and cell death by a unique mechanism of inducing DNA damage and inhibiting DNA repair.
Collapse
Affiliation(s)
- Michael P Croglio
- Department of Human Science, NHS, Georgetown University Medical Center, NW, Washington DC, USA
| | - Jefferson M Haake
- Department of Human Science, NHS, Georgetown University Medical Center, NW, Washington DC, USA
| | - Colin P Ryan
- Department of Human Science, NHS, Georgetown University Medical Center, NW, Washington DC, USA
| | - Victor S Wang
- Department of Human Science, NHS, Georgetown University Medical Center, NW, Washington DC, USA
| | - Jennifer Lapier
- Department of Human Science, NHS, Georgetown University Medical Center, NW, Washington DC, USA
| | - Jamie P Schlarbaum
- Department of Human Science, NHS, Georgetown University Medical Center, NW, Washington DC, USA
| | - Yaron Dayani
- Department of Human Science, NHS, Georgetown University Medical Center, NW, Washington DC, USA
| | - Emma Artuso
- Department of Chemistry, University of Turin, Turin, Italy
| | | | - Hinanit Koltai
- Institute of Plant Sciences, ARO, Volcani Center, Bet Dagan, Israel
| | - Keli Agama
- Developmental Therapeutics Branch and Laboratory of Molecular Pharmacology, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD, USA
| | - Yves Pommier
- Developmental Therapeutics Branch and Laboratory of Molecular Pharmacology, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD, USA
| | - Yu Chen
- Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Lucas Tricoli
- The Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, NW, Washington DC, USA
| | - Jeannine R LaRocque
- Department of Human Science, NHS, Georgetown University Medical Center, NW, Washington DC, USA
| | - Christopher Albanese
- The Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, NW, Washington DC, USA.,Department of Pathology, Georgetown University Medical Center, NW, Washington DC, USA
| | - Ronit I Yarden
- Department of Human Science, NHS, Georgetown University Medical Center, NW, Washington DC, USA.,The Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, NW, Washington DC, USA
| |
Collapse
|
31
|
Giono LE, Resnick-Silverman L, Carvajal LA, St Clair S, Manfredi JJ. Mdm2 promotes Cdc25C protein degradation and delays cell cycle progression through the G2/M phase. Oncogene 2017; 36:6762-6773. [PMID: 28806397 PMCID: PMC6002854 DOI: 10.1038/onc.2017.254] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Revised: 06/15/2017] [Accepted: 06/27/2017] [Indexed: 12/16/2022]
Abstract
Upon different types of stress, the gene encoding the mitosis-promoting phosphatase Cdc25C is transcriptionally repressed by p53, contributing to p53's enforcement of a G2 cell cycle arrest. In addition, Cdc25C protein stability is also decreased following DNA damage. Mdm2, another p53 target gene, encodes a ubiquitin ligase that negatively regulates p53 levels by ubiquitination. Ablation of Mdm2 by siRNA led to an increase in p53 protein and repression of Cdc25C gene expression. However, Cdc25C protein levels were actually increased following Mdm2 depletion. Mdm2 is shown to negatively regulate Cdc25C protein levels by reducing its half-life independently of the presence of p53. Further, Mdm2 physically interacts with Cdc25C and promotes its degradation through the proteasome in a ubiquitin-independent manner. Either Mdm2 overexpression or Cdc25C downregulation delays cell cycle progression through the G2/M phase. Thus, the repression of the Cdc25C promoter by p53, together with p53-dependent induction of Mdm2 and subsequent degradation of Cdc25C, could provide a dual mechanism by which p53 can enforce and maintain a G2/M cell cycle arrest.
Collapse
Affiliation(s)
- L E Giono
- Department of Oncological Sciences and Graduate School of Biological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - L Resnick-Silverman
- Department of Oncological Sciences and Graduate School of Biological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - L A Carvajal
- Department of Oncological Sciences and Graduate School of Biological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - S St Clair
- Department of Oncological Sciences and Graduate School of Biological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - J J Manfredi
- Department of Oncological Sciences and Graduate School of Biological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| |
Collapse
|
32
|
Liao Y, Yuan S, Chen X, Zhu P, Li J, Qin L, Liao W. Up-regulation of BRCA1-associated RING Domain 1 Promotes Hepatocellular Carcinoma Progression by Targeting Akt Signaling. Sci Rep 2017; 7:7649. [PMID: 28794477 PMCID: PMC5550490 DOI: 10.1038/s41598-017-07962-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Accepted: 07/03/2017] [Indexed: 01/07/2023] Open
Abstract
The present study was designed to investigate the potential clinical, pathological, prognostic value, role and mechanism of BRCA1-associated RING Domain 1 (BARD1) in Hepatocellular carcinoma (HCC). Quantitative real-time PCR and immunohistochemistry were performed to evaluate the expression of BARD1 mRNA and protein. The expression of BARD1 in the HCC tissue samples was markedly higher than that in the adjacent noncancerous liver tissues. Elevated BARD1 expression was positively correlated with tumor-node-metastasis stage, Barcelona-Clinic Liver Cancer stage, hepatitis B surface antigen, large tumor size, serum alpha-fetoprotein levels, and serum aspartate aminotransferase levels. Univariate and multivariate analyses revealed the BARD1 was an independent predictor for decreased progression-free survival and overall survival in HCC. In vitro experiments demonstrated that knocking down BARD1 significantly inhibited the proliferation, invasion and migration of HCC cells. Moreover, silencing BARD1 inhibit the signaling pathway via decreased the levels of Akt, mTOR, and MMP-9 and inhibited the phosphorylation of Akt (Ser473) and mTOR (Ser2248). Collectively, our findings suggest that BARD1 may be a novel diagnostic and prognostic biomarker of HCC, and up-regulation of BARD1 can contribute to HCC progression by targeting Akt signaling.
Collapse
Affiliation(s)
- Yan Liao
- Laboratory of Hepatobiliary and Pancreatic Surgery, Affiliated Hospital of Guilin Medical University, Guilin, Guangxi, P.R. China.,Disease Prevention and Control Center of Guilin, Guilin, Guangxi, P.R. China
| | - Shengguang Yuan
- Department of Hepatobiliary and Pancreatic Surgery, Affiliated Hospital of Guilin Medical University, Guilin, Guangxi, P.R. China
| | - Xinhuang Chen
- Laboratory of Hepatobiliary and Pancreatic Surgery, Affiliated Hospital of Guilin Medical University, Guilin, Guangxi, P.R. China
| | - Pengpeng Zhu
- Laboratory of Hepatobiliary and Pancreatic Surgery, Affiliated Hospital of Guilin Medical University, Guilin, Guangxi, P.R. China
| | - Jun Li
- Laboratory of Hepatobiliary and Pancreatic Surgery, Affiliated Hospital of Guilin Medical University, Guilin, Guangxi, P.R. China
| | - Liling Qin
- Laboratory of Hepatobiliary and Pancreatic Surgery, Affiliated Hospital of Guilin Medical University, Guilin, Guangxi, P.R. China
| | - Weijia Liao
- Laboratory of Hepatobiliary and Pancreatic Surgery, Affiliated Hospital of Guilin Medical University, Guilin, Guangxi, P.R. China.
| |
Collapse
|
33
|
Kawaguchi T, Komatsu S, Ichikawa D, Hirajima S, Nishimura Y, Konishi H, Shiozaki A, Fujiwara H, Okamoto K, Tsuda H, Otsuji E. Overexpression of TRIM44 is related to invasive potential and malignant outcomes in esophageal squamous cell carcinoma. Tumour Biol 2017; 39:1010428317700409. [PMID: 28618928 DOI: 10.1177/1010428317700409] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Recent studies have shown that some members of the tripartite motif-containing protein family function as important regulators for carcinogenesis. In this study, we investigated whether tripartite motif-containing protein 44 acts as a cancer-promoting gene through its overexpression in esophageal squamous cell carcinoma. We analyzed esophageal squamous cell carcinoma cell lines to evaluate malignant potential and also analyzed 68 primary tumors to evaluate clinical relevance of tripartite motif-containing protein 44 protein in esophageal squamous cell carcinoma patients. Expression of the tripartite motif-containing protein 44 protein was detected in esophageal squamous cell carcinoma cell lines (8/14 cell lines; 57%) and primary tumor samples of esophageal squamous cell carcinoma (39/68 cases; 57%). Knockdown of tripartite motif-containing protein 44 expression in esophageal squamous cell carcinoma cells using several specific small interfering RNAs inhibited cell migration and invasion, but not cell proliferation. Immunohistochemical analysis demonstrated that the overexpression of the tripartite motif-containing protein 44 protein in the tumor infiltrated region was associated with the status of lymph node metastasis ( p = 0.049), and the overall survival rates were significantly worse among patients with tripartite motif-containing protein 44-overexpressing tumors than those with non-expressing tumors ( p = 0.029). Moreover, multivariate Cox regression model identified that overexpression of the tripartite motif-containing protein 44 protein was an independent worse prognostic factor (hazard ratio = 2.815; p = 0.041), as well as lymphatic invasion (hazard ratio = 2.735; p = 0.037). These results suggest that tripartite motif-containing protein 44 protein could play a crucial role in tumor invasion through its overexpression and highlight its usefulness as a predictor and potential therapeutic target in esophageal squamous cell carcinoma.
Collapse
Affiliation(s)
- Tsutomu Kawaguchi
- 1 Division of Digestive Surgery, Department of Surgery, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Shuhei Komatsu
- 1 Division of Digestive Surgery, Department of Surgery, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Daisuke Ichikawa
- 1 Division of Digestive Surgery, Department of Surgery, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Shoji Hirajima
- 1 Division of Digestive Surgery, Department of Surgery, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Yukihisa Nishimura
- 1 Division of Digestive Surgery, Department of Surgery, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Hirotaka Konishi
- 1 Division of Digestive Surgery, Department of Surgery, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Atsushi Shiozaki
- 1 Division of Digestive Surgery, Department of Surgery, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Hitoshi Fujiwara
- 1 Division of Digestive Surgery, Department of Surgery, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Kazuma Okamoto
- 1 Division of Digestive Surgery, Department of Surgery, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Hitoshi Tsuda
- 2 Department of Pathology, National Cancer Center Hospital, Tokyo, Japan.,3 Department of Basic Pathology, National Defense Medical College, Saitama, Japan
| | - Eigo Otsuji
- 1 Division of Digestive Surgery, Department of Surgery, Kyoto Prefectural University of Medicine, Kyoto, Japan
| |
Collapse
|
34
|
Ren Z, Aerts JL, Vandenplas H, Wang JA, Gorbenko O, Chen JP, Giron P, Heirman C, Goyvaerts C, Zacksenhaus E, Minden MD, Stambolic V, Breckpot K, De Grève J. Phosphorylated STAT5 regulates p53 expression via BRCA1/BARD1-NPM1 and MDM2. Cell Death Dis 2016; 7:e2560. [PMID: 28005077 PMCID: PMC5260985 DOI: 10.1038/cddis.2016.430] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2015] [Revised: 10/18/2016] [Accepted: 10/19/2016] [Indexed: 12/31/2022]
Abstract
Signal transducer and activator of transcription 5 (STAT5) and nucleophosmin (NPM1) are critical regulators of multiple biological and pathological processes. Although a reciprocal regulatory relationship was established between STAT5A and a NPM–ALK fusion protein in T-cell lymphoma, no direct connection between STAT5 and wild-type NPM1 has been documented. Here we demonstrate a mutually regulatory relationship between STAT5 and NPM1. Induction of STAT5 phosphorylation at Y694 (P-STAT5) diminished NPM1 expression, whereas inhibition of STAT5 phosphorylation enhanced NPM1 expression. Conversely, NPM1 not only negatively regulated STAT5 phosphorylation but also preserved unphosphorylated STAT5 level. Mechanistically, we show that NPM1 downregulation by P-STAT5 is mediated by impairing the BRCA1-BARD1 ubiquitin ligase, which controls the stability of NPM1. In turn, decreased NPM1 levels led to suppression of p53 expression, resulting in enhanced cell survival. This study reveals a new STAT5 signaling pathway regulating p53 expression via NPM1 and uncovers new therapeutic targets for anticancer treatment in tumors driven by STAT5 signaling.
Collapse
Affiliation(s)
- Zhuo Ren
- Laboratory of Medical and Molecular Oncology (LMMO), Department of Medical Oncology, Vrije Universiteit Brussel, Brussels, Belgium.,Department of General Surgery, The First People's Hospital of Shanghai, Shanghai Jiaotong University, Shanghai, China.,Department of Medical Oncology, Oncologisch Centrum of the Universitair Ziekenhuis Brussel, Vrije Universiteit Brussel, Brussels, Belgium.,Princess Margaret Cancer Centre, University Health Network, Toronto, ON, Canada
| | - Joeri L Aerts
- Laboratory of Molecular and Cellular Therapy, Department of Physiology and Immunology, Vrije Universiteit Brussel, Brussels, Belgium
| | - Hugo Vandenplas
- Laboratory of Medical and Molecular Oncology (LMMO), Department of Medical Oncology, Vrije Universiteit Brussel, Brussels, Belgium.,Department of Medical Oncology, Oncologisch Centrum of the Universitair Ziekenhuis Brussel, Vrije Universiteit Brussel, Brussels, Belgium
| | - Jiance A Wang
- Department of Medicine and Medical Biophysics, University of Toronto, Toronto, ON, Canada
| | - Olena Gorbenko
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON, Canada
| | - Jack P Chen
- Department of Medicine and Medical Biophysics, University of Toronto, Toronto, ON, Canada
| | - Philippe Giron
- Laboratory of Medical and Molecular Oncology (LMMO), Department of Medical Oncology, Vrije Universiteit Brussel, Brussels, Belgium.,Department of Medical Oncology, Oncologisch Centrum of the Universitair Ziekenhuis Brussel, Vrije Universiteit Brussel, Brussels, Belgium
| | - Carlo Heirman
- Laboratory of Molecular and Cellular Therapy, Department of Physiology and Immunology, Vrije Universiteit Brussel, Brussels, Belgium
| | - Cleo Goyvaerts
- Laboratory of Molecular and Cellular Therapy, Department of Physiology and Immunology, Vrije Universiteit Brussel, Brussels, Belgium
| | - Eldad Zacksenhaus
- Department of Medicine and Medical Biophysics, University of Toronto, Toronto, ON, Canada.,Toronto General Research Institute, University Health Network, Toronto, ON, Canada
| | - Mark D Minden
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON, Canada.,Department of Medicine and Medical Biophysics, University of Toronto, Toronto, ON, Canada
| | - Vuk Stambolic
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON, Canada.,Department of Medicine and Medical Biophysics, University of Toronto, Toronto, ON, Canada
| | - Karine Breckpot
- Laboratory of Molecular and Cellular Therapy, Department of Physiology and Immunology, Vrije Universiteit Brussel, Brussels, Belgium
| | - Jacques De Grève
- Laboratory of Medical and Molecular Oncology (LMMO), Department of Medical Oncology, Vrije Universiteit Brussel, Brussels, Belgium.,Department of Medical Oncology, Oncologisch Centrum of the Universitair Ziekenhuis Brussel, Vrije Universiteit Brussel, Brussels, Belgium
| |
Collapse
|
35
|
Asanagi M, Yamada S, Hirata N, Itagaki H, Kotake Y, Sekino Y, Kanda Y. Tributyltin induces G2/M cell cycle arrest via NAD(+)-dependent isocitrate dehydrogenase in human embryonic carcinoma cells. J Toxicol Sci 2016; 41:207-15. [PMID: 26961604 DOI: 10.2131/jts.41.207] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Organotin compounds, such as tributyltin (TBT), are well-known endocrine-disrupting chemicals (EDCs). We have recently reported that TBT induces growth arrest in the human embryonic carcinoma cell line NT2/D1 at nanomolar levels by inhibiting NAD(+)-dependent isocitrate dehydrogenase (NAD-IDH), which catalyzes the irreversible conversion of isocitrate to α-ketoglutarate. However, the molecular mechanisms by which NAD-IDH mediates TBT toxicity remain unclear. In the present study, we examined whether TBT at nanomolar levels affects cell cycle progression in NT2/D1 cells. Propidium iodide staining revealed that TBT reduced the ratio of cells in the G1 phase and increased the ratio of cells in the G2/M phase. TBT also reduced cell division cycle 25C (cdc25C) and cyclin B1, which are key regulators of G2/M progression. Furthermore, apigenin, an inhibitor of NAD-IDH, mimicked the effects of TBT. The G2/M arrest induced by TBT was abolished by NAD-IDHα knockdown. Treatment with a cell-permeable α-ketoglutarate analogue recovered the effect of TBT, suggesting the involvement of NAD-IDH. Taken together, our data suggest that TBT at nanomolar levels induced G2/M cell cycle arrest via NAD-IDH in NT2/D1 cells. Thus, cell cycle analysis in embryonic cells could be used to assess cytotoxicity associated with nanomolar level exposure of EDCs.
Collapse
Affiliation(s)
- Miki Asanagi
- Division of Pharmacology, National Institute of Health Sciences
| | | | | | | | | | | | | |
Collapse
|
36
|
Brandeis M. Slip slidin' away of mitosis with CRL2Zyg11. J Cell Biol 2016; 215:143-145. [PMID: 27810907 PMCID: PMC5084651 DOI: 10.1083/jcb.201609086] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2016] [Accepted: 09/19/2016] [Indexed: 11/22/2022] Open
Abstract
The spindle assembly checkpoint arrests mitotic cells by preventing degradation of cyclin B1 by the anaphase-promoting complex/cyclosome, but some cells evade this checkpoint and slip out of mitosis. Balachandran et al. (2016. J. Cell Biol. http://dx.doi.org/10.1083/jcb.201601083) show that the E3 ligase CRL2ZYG11 degrades cyclin B1, allowing mitotic slippage.
Collapse
Affiliation(s)
- Michael Brandeis
- Department of Genetics, The Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem Safra Campus, Jerusalem 9190401, Israel
| |
Collapse
|
37
|
Balachandran RS, Heighington CS, Starostina NG, Anderson JW, Owen DL, Vasudevan S, Kipreos ET. The ubiquitin ligase CRL2ZYG11 targets cyclin B1 for degradation in a conserved pathway that facilitates mitotic slippage. J Cell Biol 2016; 215:151-166. [PMID: 27810909 PMCID: PMC5084644 DOI: 10.1083/jcb.201601083] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Accepted: 09/22/2016] [Indexed: 12/18/2022] Open
Abstract
Cells arrested in mitosis by inactivation of the APC/C complex sometimes manage to exit mitosis in a process called mitotic slippage, which helps cancer cells circumvent chemotherapy drugs. Balachandran et al. show that mitotic slippage occurs as a result of targeting of cyclin B1 for degradation by the ligase CRL2ZYG11. The anaphase-promoting complex/cyclosome (APC/C) ubiquitin ligase is known to target the degradation of cyclin B1, which is crucial for mitotic progression in animal cells. In this study, we show that the ubiquitin ligase CRL2ZYG-11 redundantly targets the degradation of cyclin B1 in Caenorhabditis elegans and human cells. In C. elegans, both CRL2ZYG-11 and APC/C are required for proper progression through meiotic divisions. In human cells, inactivation of CRL2ZYG11A/B has minimal effects on mitotic progression when APC/C is active. However, when APC/C is inactivated or cyclin B1 is overexpressed, CRL2ZYG11A/B-mediated degradation of cyclin B1 is required for normal progression through metaphase. Mitotic cells arrested by the spindle assembly checkpoint, which inactivates APC/C, often exit mitosis in a process termed “mitotic slippage,” which generates tetraploid cells and limits the effectiveness of antimitotic chemotherapy drugs. We show that ZYG11A/B subunit knockdown, or broad cullin–RING ubiquitin ligase inactivation with the small molecule MLN4924, inhibits mitotic slippage in human cells, suggesting the potential for antimitotic combination therapy.
Collapse
Affiliation(s)
| | | | | | - James W Anderson
- Department of Cellular Biology, University of Georgia, Athens, GA 30602
| | - David L Owen
- Department of Cellular Biology, University of Georgia, Athens, GA 30602
| | | | - Edward T Kipreos
- Department of Cellular Biology, University of Georgia, Athens, GA 30602
| |
Collapse
|
38
|
Lo PK, Zhang Y, Wolfson B, Gernapudi R, Yao Y, Duru N, Zhou Q. Dysregulation of the BRCA1/long non-coding RNA NEAT1 signaling axis contributes to breast tumorigenesis. Oncotarget 2016; 7:65067-65089. [PMID: 27556296 PMCID: PMC5323139 DOI: 10.18632/oncotarget.11364] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Accepted: 08/10/2016] [Indexed: 01/15/2023] Open
Abstract
Dysregulation of long non-codng RNA (lncRNA) expression has been found to contribute to tumorigenesis. However, the roles of lncRNAs in BRCA1-related breast cancer remain largely unknown. In this study, we delineate the role of the novel BRCA1/lncRNA NEAT1 signaling axis in breast tumorigenesis. BRCA1 inhibits NEAT1 expression potentially through binding to its genomic binding site upstream of the NEAT1 gene. BRCA1 deficiency in human normal/cancerous breast cells and mouse mammary glands leads to NEAT1 overexpression. Our studies show that NEAT1 upregulation resulting from BRCA1 deficiency stimulates in vitro and in vivo breast tumorigenicity. We have further identified molecular mediators downstream of the BRCA1/NEAT1 axis. NEAT1 epigenetically silences miR-129-5p expression by promoting the DNA methylation of the CpG island in the miR-129 gene. Silencing of miR-129-5p expression by NEAT1 results in upregulation of WNT4 expression, a target of miR-129-5p, which leads to activation of oncogenic WNT signaling. Our functional studies indicate that this NEAT1/miR-129-5p/WNT4 axis contributes to the tumorigenic effects of BRCA1 deficiency. Finally our in silico expression correlation analysis suggests the existence of the BRCA1/NEAT1/miR-129-5p axis in breast cancer. Our findings, taken together, suggest that the dysregulation of the BRCA1/NEAT1/miR-129-5p/WNT4 signaling axis is involved in promoting breast tumorigenesis.
Collapse
Affiliation(s)
- Pang-Kuo Lo
- Department of Biochemistry and Molecular Biology, Greenebaum Cancer Center, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Yongshu Zhang
- Department of Biochemistry and Molecular Biology, Greenebaum Cancer Center, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Benjamin Wolfson
- Department of Biochemistry and Molecular Biology, Greenebaum Cancer Center, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Ramkishore Gernapudi
- Department of Biochemistry and Molecular Biology, Greenebaum Cancer Center, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Yuan Yao
- Department of Biochemistry and Molecular Biology, Greenebaum Cancer Center, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Nadire Duru
- Department of Biochemistry and Molecular Biology, Greenebaum Cancer Center, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Qun Zhou
- Department of Biochemistry and Molecular Biology, Greenebaum Cancer Center, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| |
Collapse
|
39
|
Jiang Y, Chen HC, Su X, Thompson PA, Liu X, Do KA, Wierda W, Keating MJ, Plunkett W. ATM function and its relationship with ATM gene mutations in chronic lymphocytic leukemia with the recurrent deletion (11q22.3-23.2). Blood Cancer J 2016; 6:e465. [PMID: 27588518 PMCID: PMC5056966 DOI: 10.1038/bcj.2016.69] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Accepted: 07/06/2016] [Indexed: 01/02/2023] Open
Abstract
Approximately 10–20% of chronic lymphocytic leukemia (CLL) patients exhibit del(11q22–23) before treatment, this cohort increases to over 40% upon progression following chemoimmunotherapy. The coding sequence of the DNA damage response gene, ataxia-telangiectasia-mutated (ATM), is contained in this deletion. The residual ATM allele is frequently mutated, suggesting a relationship between gene function and clinical response. To investigate this possibility, we sought to develop and validate an assay for the function of ATM protein in these patients. SMC1 (structural maintenance of chromosomes 1) and KAP1 (KRAB-associated protein 1) were found to be unique substrates of ATM kinase by immunoblot detection following ionizing radiation. Using a pool of eight fluorescence in situ hybridization-negative CLL samples as a standard, the phosphorylation of SMC1 and KAP1 from 46 del (11q22–23) samples was analyzed using normal mixture model-based clustering. This identified 13 samples (28%) that were deficient in ATM function. Targeted sequencing of the ATM gene of these samples, with reference to genomic DNA, revealed 12 somatic mutations and 15 germline mutations in these samples. No strong correlation was observed between ATM mutation and function. Therefore, mutation status may not be taken as an indicator of ATM function. Rather, a direct assay of the kinase activity should be used in the development of therapies.
Collapse
Affiliation(s)
- Y Jiang
- Department of Experimental Therapeutics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - H-C Chen
- Department of Biostatistics, Houston, TX, USA
| | - X Su
- Department of Bioinformatics and Computational Biology, Houston, TX, USA
| | - P A Thompson
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - X Liu
- Department of Experimental Therapeutics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - K-A Do
- Department of Biostatistics, Houston, TX, USA
| | - W Wierda
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - M J Keating
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - W Plunkett
- Department of Experimental Therapeutics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.,Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| |
Collapse
|
40
|
Human TRIB2 Oscillates during the Cell Cycle and Promotes Ubiquitination and Degradation of CDC25C. Int J Mol Sci 2016; 17:ijms17091378. [PMID: 27563873 PMCID: PMC5037658 DOI: 10.3390/ijms17091378] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Revised: 08/04/2016] [Accepted: 08/18/2016] [Indexed: 12/13/2022] Open
Abstract
Tribbles homolog 2 (TRIB2) is a member of the mammalian Tribbles family of serine/threonine pseudokinases (TRIB1-3). Studies of TRIB2 indicate that many of the molecular interactions between the single Drosophila Tribbles (Trbl) protein and interacting partners are evolutionary conserved. In this study, we examined the relationship between TRIB2 and cell division cycle 25 (CDC25) family of dual-specificity protein phosphatases (mammalian homologues of Drosophila String), which are key physiological cell cycle regulators. Using co-immunoprecipitation we demonstrate that TRIB2 interacts with CDC25B and CDC25C selectively. Forced overexpression of TRIB2 caused a marked decrease in total CDC25C protein levels. Following inhibition of the proteasome, CDC25C was stabilized in the nuclear compartment. This implicates TRIB2 as a regulator of nuclear CDC25C turnover. In complementary ubiquitination assays, we show that TRIB2-mediated degradation of CDC25C is associated with lysine-48-linked CDC25C polyubiquitination driven by the TRIB2 kinase-like domain. A cell cycle associated role for TRIB2 is further supported by the cell cycle regulated expression of TRIB2 protein levels. Our findings reveal mitotic CDC25C as a new target of TRIB2 that is degraded via the ubiquitin proteasome system. Inappropriate CDC25C regulation could mechanistically underlie TRIB2 mediated regulation of cellular proliferation in neoplastic cells.
Collapse
|
41
|
Drost R, Dhillon KK, van der Gulden H, van der Heijden I, Brandsma I, Cruz C, Chondronasiou D, Castroviejo-Bermejo M, Boon U, Schut E, van der Burg E, Wientjens E, Pieterse M, Klijn C, Klarenbeek S, Loayza-Puch F, Elkon R, van Deemter L, Rottenberg S, van de Ven M, Dekkers DHW, Demmers JAA, van Gent DC, Agami R, Balmaña J, Serra V, Taniguchi T, Bouwman P, Jonkers J. BRCA1185delAG tumors may acquire therapy resistance through expression of RING-less BRCA1. J Clin Invest 2016; 126:2903-18. [PMID: 27454287 DOI: 10.1172/jci70196] [Citation(s) in RCA: 94] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2013] [Accepted: 05/09/2016] [Indexed: 12/19/2022] Open
Abstract
Heterozygous germline mutations in breast cancer 1 (BRCA1) strongly predispose women to breast cancer. BRCA1 plays an important role in DNA double-strand break (DSB) repair via homologous recombination (HR), which is important for tumor suppression. Although BRCA1-deficient cells are highly sensitive to treatment with DSB-inducing agents through their HR deficiency (HRD), BRCA1-associated tumors display heterogeneous responses to platinum drugs and poly(ADP-ribose) polymerase (PARP) inhibitors in clinical trials. It is unclear whether all pathogenic BRCA1 mutations have similar effects on the response to therapy. Here, we have investigated mammary tumorigenesis and therapy sensitivity in mice carrying the Brca1185stop and Brca15382stop alleles, which respectively mimic the 2 most common BRCA1 founder mutations, BRCA1185delAG and BRCA15382insC. Both the Brca1185stop and Brca15382stop mutations predisposed animals to mammary tumors, but Brca1185stop tumors responded markedly worse to HRD-targeted therapy than did Brca15382stop tumors. Mice expressing Brca1185stop mutations also developed therapy resistance more rapidly than did mice expressing Brca15382stop. We determined that both murine Brca1185stop tumors and human BRCA1185delAG breast cancer cells expressed a really interesting new gene domain-less (RING-less) BRCA1 protein that mediated resistance to HRD-targeted therapies. Together, these results suggest that expression of RING-less BRCA1 may serve as a marker to predict poor response to DSB-inducing therapy in human cancer patients.
Collapse
|
42
|
Ozden O, Bishehsari F, Bauer J, Park SH, Jana A, Baik SH, Sporn JC, Staudacher JJ, Yazici C, Krett N, Jung B. Expression of an Oncogenic BARD1 Splice Variant Impairs Homologous Recombination and Predicts Response to PARP-1 Inhibitor Therapy in Colon Cancer. Sci Rep 2016; 6:26273. [PMID: 27197561 PMCID: PMC4873788 DOI: 10.1038/srep26273] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2015] [Accepted: 04/26/2016] [Indexed: 01/30/2023] Open
Abstract
BRCA1-associated RING domain protein 1 (BARD1) stabilizes BRCA1 protein by forming a heterodimeric RING-RING complex, and impacts function of BRCA1, including homologous recombination (HR) repair. Although colon cancer cells usually express wild type BRCA1, presence of an oncogenic BARD1 splice variant (SV) in select cancers may render BRCA1 dysfunctional and allow cells to become sensitive to HR targeting therapies. We previously reported association of loss of full-length (FL) BARD1 with poor prognosis in colon cancer as well as expression of various BARD1 SVs with unknown function. Here we show that loss of BARD1 function through the expression of a BARD1 SV, BARD1β, results in a more malignant phenotype with decreased RAD51 foci formation, reduced BRCA1 E3 ubiquitin ligase activity, and decreased nuclear BRCA1 protein localization. BARD1β sensitizes colon cancer cells to poly ADP ribose polymerase 1 (PARP-1) inhibition even in a FL BRCA1 background. These results suggest that expression of BARD1β may serve as a future biomarker to assess suitability of colon cancers for HR targeting with PARP-1 inhibitors in treatment of advanced colon cancer.
Collapse
Affiliation(s)
- Ozkan Ozden
- Department of Medicine, Division of Gastroenterology, University of Illinois at Chicago, Chicago, IL 60612, U.S.A
| | - Faraz Bishehsari
- Department of Internal Medicine, Division of Gastroenterology, Rush University Medical Center, Chicago, IL, 60612, U.S.A
| | - Jessica Bauer
- Department of Medicine, Division of Gastroenterology, University of Illinois at Chicago, Chicago, IL 60612, U.S.A
| | - Seong-Hoon Park
- Department of Radiation Oncology, Robert Lurie Cancer Center, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, U.S.A
| | - Arundhati Jana
- Department of Medicine, Division of Gastroenterology, University of Illinois at Chicago, Chicago, IL 60612, U.S.A
| | - Seung Hyun Baik
- Department of Medicine, Division of Gastroenterology, University of Illinois at Chicago, Chicago, IL 60612, U.S.A
| | - Judith C Sporn
- Department of Medicine, Division of Gastroenterology, University of Illinois at Chicago, Chicago, IL 60612, U.S.A
| | - Jonas J Staudacher
- Department of Medicine, Division of Gastroenterology, University of Illinois at Chicago, Chicago, IL 60612, U.S.A
| | - Cemal Yazici
- Department of Medicine, Division of Gastroenterology, University of Illinois at Chicago, Chicago, IL 60612, U.S.A
| | - Nancy Krett
- Department of Medicine, Division of Gastroenterology, University of Illinois at Chicago, Chicago, IL 60612, U.S.A
| | - Barbara Jung
- Department of Medicine, Division of Gastroenterology, University of Illinois at Chicago, Chicago, IL 60612, U.S.A
| |
Collapse
|
43
|
Vriend J, Reiter RJ. Breast cancer cells: Modulation by melatonin and the ubiquitin-proteasome system--a review. Mol Cell Endocrinol 2015; 417:1-9. [PMID: 26363225 DOI: 10.1016/j.mce.2015.09.001] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/11/2015] [Accepted: 09/01/2015] [Indexed: 02/07/2023]
Abstract
Melatonin inhibits human breast cancer cells stimulated with estrogen. This antiproliferative action depends on the presence of the estrogen receptor alpha (ERα) in the human MCF-7 cell line and is strictly dose-dependent. Since researchers concerned with melatonin and breast cancer have not considered the relevance of the ubiquitin-proteasome system to this research in this review we do so. The fact that the first breast cancer susceptibility gene to be identified, Brca1, functions as a ubiquitin ligase indicates that the ubiquitin-proteasome system has a role in regulating susceptibility to breast cancer. While mutations of this gene increase the incidence of breast cancer, the wild type gene suppresses estrogen-dependent transcriptional events relying on the estrogen receptor ERα. Three other ubiquitin ligases, SCF(Skp2), E6AP and APC, interact directly with ERα at the ERE and AP-1 promoters of ERα target genes. Melatonin, like proteasome inhibitors, decreases estrogen-induced gene transcription. Indeed, it has been reported that melatonin specifically inhibits estrogen-induced transcription mediated by ERα at the ERE and AP1 gene promoters. Herein, we present a model in which the inhibitory action of melatonin on MCF-7 cells is mediated, directly or indirectly, by the ubiquitin-proteasome system. In this model ERα, apoptotic proteins, and cell cycle proteins, all influenced by melatonin, are substrates of key ubiquitin ligases including SCF(Skp2), E6AP, and SCF(B-TrCP). Since dysfunction of the ubiquitin-proteasome system is a risk factor for breast cancer, this model provides a context in which to test the clinical potential, and limitations, of melatonin and proteasome inhibitors.
Collapse
Affiliation(s)
- Jerry Vriend
- Department of Human Anatomy and Cell Science, University of Manitoba, Winnipeg, MB, Canada.
| | - Russel J Reiter
- Department of Cellular and Structural Biology, UT Health Science Center San Antonio, TX, USA
| |
Collapse
|
44
|
Suppression of BRCA1 sensitizes cells to proteasome inhibitors. Cell Death Dis 2014; 5:e1580. [PMID: 25522274 PMCID: PMC4649846 DOI: 10.1038/cddis.2014.537] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2014] [Revised: 11/06/2014] [Accepted: 11/10/2014] [Indexed: 02/08/2023]
Abstract
BRCA1 is a multifunctional protein best known for its role in DNA repair and association with breast and ovarian cancers. To uncover novel biologically significant molecular functions of BRCA1, we tested a panel of 198 approved and experimental drugs to inhibit growth of MDA-MB-231 breast cancer cells depleted for BRCA1 by siRNA. 26S proteasome inhibitors bortezomib and carfilzomib emerged as a new class of selective BRCA1-targeting agents. The effect was confirmed in HeLa and U2OS cancer cell lines using two independent siRNAs, and in mouse embryonic stem (ES) cells with inducible deletion of Brca1. Bortezomib treatment did not cause any increase in nuclear foci containing phosphorylated histone H2AX, and knockdown of BRCA2 did not entail sensitivity to bortezomib, suggesting that the DNA repair function of BRCA1 may not be directly involved. We found that a toxic effect of bortezomib on BRCA1-depleted cells is mostly due to deregulated cell cycle checkpoints mediated by RB1-E2F pathway and 53BP1. Similar to BRCA1, depletion of RB1 also conferred sensitivity to bortezomib, whereas suppression of E2F1 or 53BP1 together with BRCA1 reduced induction of apoptosis after bortezomib treatment. A gene expression microarray study identified additional genes activated by bortezomib treatment only in the context of inactivation of BRCA1 including a critical involvement of the ERN1-mediated unfolded protein response. Our data indicate that BRCA1 has a novel molecular function affecting cell cycle checkpoints in a manner dependent on the 26S proteasome activity.
Collapse
|
45
|
Pickholtz I, Saadyan S, Keshet GI, Wang VS, Cohen R, Bouwman P, Jonkers J, Byers SW, Papa MZ, Yarden RI. Cooperation between BRCA1 and vitamin D is critical for histone acetylation of the p21waf1 promoter and growth inhibition of breast cancer cells and cancer stem-like cells. Oncotarget 2014; 5:11827-46. [PMID: 25460500 PMCID: PMC4322975 DOI: 10.18632/oncotarget.2582] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2014] [Accepted: 10/09/2014] [Indexed: 12/19/2022] Open
Abstract
Carriers of germline mutations in the BRCA1 gene have a significant increased lifetime risk for being diagnosed with breast cancer. The incomplete penetrance of BRCA1 suggests that environmental and/or genetic factors modify the risk and incidence among mutation carriers. Nutrition and particular micronutrients play a central role in modifying the phenotypic expression of a given genotype by regulating chromatin structure and gene expression. The active form of vitamin D, 1α,25-dihydroxyvitamin D3, is a potent inhibitor of breast cancer growth. Here we report that two non-calcemic analogues of 1α,25-dihydroxyvitamin D3, seocalcitol (EB1089) and QW-1624F2-2, collaborate with BRCA1 in mediating growth inhibition of breast cancer cells and breast cancer stem-like cells. EB1089 induces a G1/S phase growth arrest that coincides with induction of p21waf1 expression only in BRCA1-expressing cells. A complete knockdown of BRCA1 or p21waf1 renders the cells unresponsive to EB1089. Furthermore, we show that in the presence of ligand, BRCA1 associates with vitamin D receptor (VDR) and the complex co-occupies vitamin D responsive elements (VDRE) at the CDKN1A (p21waf1) promoter and enhances acetylation of histone H3 and H4 at these sites. Thus, BRCA1 expression is critical for mediating the biological impact of vitamin D3 in breast tumor cells.
Collapse
Affiliation(s)
- Itay Pickholtz
- Laboratory of Genomic Applications, Department of Surgical Oncology, Sheba Medical Center, Ramat-Gan 52621, Israel
- Sheba Cancer Research Center, Sheba Medical Center, Ramat-Gan 52621, Israel
- Sackler school of Medicine, Tel Aviv University, Tel Aviv 69978, Israel
| | - Shira Saadyan
- Laboratory of Genomic Applications, Department of Surgical Oncology, Sheba Medical Center, Ramat-Gan 52621, Israel
| | - Gilmor I. Keshet
- Sheba Cancer Research Center, Sheba Medical Center, Ramat-Gan 52621, Israel
| | - Victor S. Wang
- Department of Human Science, Georgetown University Medical Center, Washington DC 20057, USA
| | - Rachel Cohen
- Laboratory of Genomic Applications, Department of Surgical Oncology, Sheba Medical Center, Ramat-Gan 52621, Israel
| | - Peter Bouwman
- Division of Molecular Pathology and Cancer Genomic Center, The Netherland Cancer Institute, Amsterdam 1066, The Netherlands
| | - Jos Jonkers
- Division of Molecular Pathology and Cancer Genomic Center, The Netherland Cancer Institute, Amsterdam 1066, The Netherlands
| | - Stephen W. Byers
- Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, NW Washington DC 20057, USA
| | - Moshe Z. Papa
- Laboratory of Genomic Applications, Department of Surgical Oncology, Sheba Medical Center, Ramat-Gan 52621, Israel
- Sackler school of Medicine, Tel Aviv University, Tel Aviv 69978, Israel
| | - Ronit I. Yarden
- Laboratory of Genomic Applications, Department of Surgical Oncology, Sheba Medical Center, Ramat-Gan 52621, Israel
- Sheba Cancer Research Center, Sheba Medical Center, Ramat-Gan 52621, Israel
- Department of Human Science, Georgetown University Medical Center, Washington DC 20057, USA
- Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, NW Washington DC 20057, USA
| |
Collapse
|
46
|
Shiozaki A, Nako Y, Ichikawa D, Konishi H, Komatsu S, Kubota T, Fujiwara H, Okamoto K, Kishimoto M, Marunaka Y, Otsuji E. Role of the Na +/K +/2Cl - cotransporter NKCC1 in cell cycle progression in human esophageal squamous cell carcinoma. World J Gastroenterol 2014; 20:6844-6859. [PMID: 24944475 PMCID: PMC4051924 DOI: 10.3748/wjg.v20.i22.6844] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/28/2013] [Revised: 01/17/2014] [Accepted: 02/20/2014] [Indexed: 02/06/2023] Open
Abstract
AIM: To investigate the role of Na+/K+/2Cl- cotransporter 1 (NKCC1) in the regulation of genes involved in cell cycle progression and the clinicopathological significance of its expression in esophageal squamous cell carcinoma (ESCC).
METHODS: An immunohistochemical analysis was performed on 68 primary tumor samples obtained from ESCC patients that underwent esophagectomy. NKCC1 expression in human ESCC cell lines was analyzed by Western blotting. Knockdown experiments were conducted using NKCC1 small interfering RNA, and the effects on cell cycle progression were analyzed. The gene expression profiles of cells were analyzed by microarray analysis.
RESULTS: Immunohistochemical staining showed that NKCC1 was primarily found in the cytoplasm of carcinoma cells and that its expression was related to the histological degree of differentiation of SCC. NKCC1 was highly expressed in KYSE170 cells. Depletion of NKCC1 in these cells inhibited cell proliferation via G2/M phase arrest. Microarray analysis identified 2527 genes with altered expression levels in NKCC1depleted KYSE170. Pathway analysis showed that the top-ranked canonical pathway was the G2/M DNA damage checkpoint regulation pathway, which involves MAD2L1, DTL, BLM, CDC20, BRCA1, and E2F5.
CONCLUSION: These results suggest that the expression of NKCC1 in ESCC may affect the G2/M checkpoint and may be related to the degree of histological differentiation of SCCs. We have provided a deeper understanding of the role of NKCC1 as a mediator and/or a biomarker in ESCC.
Collapse
MESH Headings
- Aged
- Biomarkers, Tumor/genetics
- Biomarkers, Tumor/metabolism
- Blotting, Western
- Carcinoma, Squamous Cell/genetics
- Carcinoma, Squamous Cell/metabolism
- Carcinoma, Squamous Cell/pathology
- Cell Cycle Proteins/genetics
- Cell Cycle Proteins/metabolism
- Cell Differentiation
- Cell Line, Tumor
- Cell Proliferation
- Esophageal Neoplasms/genetics
- Esophageal Neoplasms/metabolism
- Esophageal Neoplasms/pathology
- Esophageal Squamous Cell Carcinoma
- Female
- G2 Phase Cell Cycle Checkpoints/drug effects
- Gene Expression Profiling/methods
- Gene Expression Regulation, Neoplastic
- Gene Regulatory Networks
- Humans
- Immunohistochemistry
- Male
- Middle Aged
- Oligonucleotide Array Sequence Analysis
- RNA Interference
- Signal Transduction
- Sodium Potassium Chloride Symporter Inhibitors/pharmacology
- Solute Carrier Family 12, Member 2/drug effects
- Solute Carrier Family 12, Member 2/genetics
- Solute Carrier Family 12, Member 2/metabolism
- Transfection
Collapse
|
47
|
Wang Y, Wang Z, Qi Z, Yin S, Zhang N, Liu Y, Liu M, Meng J, Zang R, Zhang Z, Yang G. The negative interplay between Aurora A/B and BRCA1/2 controls cancer cell growth and tumorigenesis via distinct regulation of cell cycle progression, cytokinesis, and tetraploidy. Mol Cancer 2014; 13:94. [PMID: 24775809 PMCID: PMC4028103 DOI: 10.1186/1476-4598-13-94] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2013] [Accepted: 04/16/2014] [Indexed: 12/22/2022] Open
Abstract
It is well known that the activation of Aurora A/B (Aur A/B) or inactivation of BRCA1/2 induces tumor formation. Others and we have reported that the mutual suppression between Aur A/B and BRCA1/2 may manipulate cancer cell growth and tumorigenesis, however, the interactive regulation and mechanism between these molecules are still elusive. In this study, by consecutive silencing of Aur A/B or/and BRCA1/2 with specific shRNAs, we showed that, in BRCA2-deficient pancreatic cancer cell line Capan-1 and in ovarian cancer cell line OVCA433, Aur A/B and BRCA1/2 inversely regulated the expression of each other likely through proteasome-mediated proteolysis but not through gene transcription. Aur A/B and BRCA1/2 conversely regulated cell cycle progression mainly through control of p53 and cyclin A. Moreover, the disruption of Aur A/B blocked abnormal cytokinesis and decreased cell multinuclearity and chromosome tetraploidy, whereas the deprivation of BRCA1/2 promoted the abnormal cytokinesis and enhanced the cell multinuclearity and tetraploidy. Furthermore, we showed by animal assays that the depletion of Aur A/B inhibited tumor growth of both cell lines, while the knockdown of BRCA1/2 promoted the tumor growth. However, the concurrent silencing of Aur A/B and BRCA1/2 diminished the effects of these molecules on the regulation of cell cycle, cytokinesis, and tetraploidy, leading to the burdened tumor sizes similar to those induced by scrambled shRNA-treated control cells. In summary, our study revealed that the negative interplay between Aur A/B and BRCA1/2 inversely controls the cell proliferation, cell cycle progression, cell multinuclearity, and tetraploidization to modulate tumorigenesis.
Collapse
Affiliation(s)
| | | | | | | | | | | | | | | | - Rongyu Zang
- Cancer Institute, Fudan University Shanghai Cancer Center, Shanghai 200032, China.
| | | | | |
Collapse
|
48
|
Yi YW, Kang HJ, Bae I. BRCA1 and Oxidative Stress. Cancers (Basel) 2014; 6:771-95. [PMID: 24704793 PMCID: PMC4074803 DOI: 10.3390/cancers6020771] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2013] [Revised: 03/20/2014] [Accepted: 03/24/2014] [Indexed: 01/07/2023] Open
Abstract
The breast cancer susceptibility gene 1 (BRCA1) has been well established as a tumor suppressor and functions primarily by maintaining genome integrity. Genome stability is compromised when cells are exposed to oxidative stress. Increasing evidence suggests that BRCA1 regulates oxidative stress and this may be another mechanism in preventing carcinogenesis in normal cells. Oxidative stress caused by reactive oxygen species (ROS) is implicated in carcinogenesis and is used strategically to treat human cancer. Thus, it is essential to understand the function of BRCA1 in oxidative stress regulation. In this review, we briefly summarize BRCA1's many binding partners and mechanisms, and discuss data supporting the function of BRCA1 in oxidative stress regulation. Finally, we consider its significance in prevention and/or treatment of BRCA1-related cancers.
Collapse
Affiliation(s)
- Yong Weon Yi
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, DC 20057, USA.
| | - Hyo Jin Kang
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, DC 20057, USA.
| | - Insoo Bae
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, DC 20057, USA.
| |
Collapse
|
49
|
Kelly R, Davey SK. Tousled-like kinase-dependent phosphorylation of Rad9 plays a role in cell cycle progression and G2/M checkpoint exit. PLoS One 2013; 8:e85859. [PMID: 24376897 PMCID: PMC3869942 DOI: 10.1371/journal.pone.0085859] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2013] [Accepted: 12/06/2013] [Indexed: 11/23/2022] Open
Abstract
Genomic integrity is preserved by checkpoints, which act to delay cell cycle progression in the presence of DNA damage or replication stress. The heterotrimeric Rad9-Rad1-Hus1 (9-1-1) complex is a PCNA-like clamp that is loaded onto DNA at structures resulting from damage and is important for initiating and maintaining the checkpoint response. Rad9 possesses a C-terminal tail that is phosphorylated constitutively and in response to cell cycle position and DNA damage. Previous studies have identified tousled-like kinase 1 (TLK1) as a kinase that may modify Rad9. Here we show that Rad9 is phosphorylated in a TLK-dependent manner in vitro and in vivo, and that T355 within the C-terminal tail is the primary targeted residue. Phosphorylation of Rad9 at T355 is quickly reduced upon exposure to ionizing radiation before returning to baseline later in the damage response. We also show that TLK1 and Rad9 interact constitutively, and that this interaction is enhanced in chromatin-bound Rad9 at later stages of the damage response. Furthermore, we demonstrate via siRNA-mediated depletion that TLK1 is required for progression through S-phase in normally cycling cells, and that cells lacking TLK1 display a prolonged G2/M arrest upon exposure to ionizing radiation, a phenotype that is mimicked by over-expression of a Rad9-T355A mutant. Given that TLK1 has previously been shown to be transiently inactivated upon phosphorylation by Chk1 in response to DNA damage, we propose that TLK1 and Chk1 act in concert to modulate the phosphorylation status of Rad9, which in turn serves to regulate the DNA damage response.
Collapse
Affiliation(s)
- Ryan Kelly
- Division of Cancer Biology and Genetics, Cancer Research Institute, Queen’s University, Kingston, Ontario, Canada
- Department of Biomedical and Molecular Sciences, Queen’s University, Kingston, Ontario, Canada
| | - Scott K. Davey
- Division of Cancer Biology and Genetics, Cancer Research Institute, Queen’s University, Kingston, Ontario, Canada
- Department of Pathology and Molecular Medicine, Queen’s University, Kingston, Ontario, Canada
- * E-mail:
| |
Collapse
|
50
|
Opportunities and hurdles in the treatment of BRCA1-related breast cancer. Oncogene 2013; 33:3753-63. [PMID: 23955079 DOI: 10.1038/onc.2013.329] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2013] [Revised: 06/13/2013] [Accepted: 06/21/2013] [Indexed: 12/11/2022]
Abstract
BRCA1 functions as a classical tumor suppressor in breast and ovarian cancer. While the role of BRCA1 in homology-directed repair of DNA double-strand breaks contributes to its tumor suppressive activity, it also renders BRCA1-deficient cells highly sensitive to DNA-damaging agents. Although BRCA1 deficiency is therefore considered to be an attractive therapeutic target, re-activation of BRCA1 by secondary mutations has been shown to cause therapy resistance. In this review, we will assess the role of BRCA1 in both hereditary and sporadic breast cancer and discuss how different functionalities of the BRCA1 protein can contribute to its tumor suppressor function. In addition, we will discuss how this knowledge on BRCA1 function can help to overcome the hurdles encountered in the clinic and improve current treatment strategies for patients with BRCA1-related breast cancer.
Collapse
|