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Harris AR, Wang T, Heng YJ, Baker GM, Le PA, Wang J, Ambrosone C, Brufsky A, Couch FJ, Modugno F, Scott CG, Vachon CM, Hankinson SE, Rosner BA, Tamimi RM, Peng C, Eliassen AH. Association of early menarche with breast tumor molecular features and recurrence. Breast Cancer Res 2024; 26:102. [PMID: 38886818 PMCID: PMC11181557 DOI: 10.1186/s13058-024-01839-0] [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: 01/17/2024] [Accepted: 05/14/2024] [Indexed: 06/20/2024] Open
Abstract
BACKGROUND Early menarche is an established risk factor for breast cancer but its molecular contribution to tumor biology and prognosis remains unclear. METHODS We profiled transcriptome-wide gene expression in breast tumors (N = 846) and tumor-adjacent normal tissues (N = 666) from women in the Nurses' Health Studies (NHS) to investigate whether early menarche (age < 12) is associated with tumor molecular and prognostic features in women with breast cancer. Multivariable linear regression and pathway analyses using competitive gene set enrichment analysis were conducted in both tumor and adjacent-normal tissue and externally validated in TCGA (N = 116). Subgroup analyses stratified on ER-status based on the tumor were also performed. PAM50 signatures were used for tumor molecular subtyping and to generate proliferation and risk of recurrence scores. We created a gene expression score using LASSO regression to capture early menarche based on 28 genes from FDR-significant pathways in breast tumor tissue in NHS and tested its association with 10-year disease-free survival in both NHS (N = 836) and METABRIC (N = 952). RESULTS Early menarche was significantly associated with 369 individual genes in adjacent-normal tissues implicated in extracellular matrix, cell adhesion, and invasion (FDR ≤ 0.1). Early menarche was associated with upregulation of cancer hallmark pathways (18 significant pathways in tumor, 23 in tumor-adjacent normal, FDR ≤ 0.1) related to proliferation (e.g. Myc, PI3K/AKT/mTOR, cell cycle), oxidative stress (e.g. oxidative phosphorylation, unfolded protein response), and inflammation (e.g. pro-inflammatory cytokines IFN α and IFN γ ). Replication in TCGA confirmed these trends. Early menarche was associated with significantly higher PAM50 proliferation scores (β = 0.082 [0.02-0.14]), odds of aggressive molecular tumor subtypes (basal-like, OR = 1.84 [1.18-2.85] and HER2-enriched, OR = 2.32 [1.46-3.69]), and PAM50 risk of recurrence score (β = 4.81 [1.71-7.92]). Our NHS-derived early menarche gene expression signature was significantly associated with worse 10-year disease-free survival in METABRIC (N = 952, HR = 1.58 [1.10-2.25]). CONCLUSIONS Early menarche is associated with more aggressive molecular tumor characteristics and its gene expression signature within tumors is associated with worse 10-year disease-free survival among women with breast cancer. As the age of onset of menarche continues to decline, understanding its relationship to breast tumor characteristics and prognosis may lead to novel secondary prevention strategies.
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Grants
- R01 CA050385 NCI NIH HHS
- R01 CA067262 NCI NIH HHS
- U01 CA176726 NCI NIH HHS
- K01AG080030 NIA NIH HHS
- SAC110014 Susan G. Komen
- P50 CA116201 NCI NIH HHS
- UM1 CA186107 NCI NIH HHS
- U19 CA148065 NCI NIH HHS
- R01 CA049449 NCI NIH HHS
- P30 CA016056 NCI NIH HHS
- R01 CA166666 NCI NIH HHS
- P01 CA087969 NCI NIH HHS
- UM1 CA186107, P01 CA87969, R01 CA49449, U01 CA176726, R01 CA67262, R01 CA50385, T32 CA009001, U19 CA148065, R01 CA166666, P30 CA016056, R35 CA253187, P50 CA116201 NIH HHS
- R35 CA253187 NCI NIH HHS
- K01 AG080030 NIA NIH HHS
- T32 CA009001 NCI NIH HHS
- National Cancer Institute Cancer Prevention Fellowship Program
- Breast Cancer Research Foundation,United States
- National Institutes of Health
- National Institute on Aging
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Affiliation(s)
- Alexandra R Harris
- Channing Division of Network Medicine, Brigham and Women's Hospital, Boston, MA, USA.
- Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA, USA.
- Integrative Tumor Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, 9609 Medical Center Drive, Bethesda, MD, 20892, USA.
| | - Tengteng Wang
- Channing Division of Network Medicine, Brigham and Women's Hospital, Boston, MA, USA
| | - Yujing J Heng
- Department of Pathology, Harvard Medical School, Boston, MA, USA
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Gabrielle M Baker
- Department of Pathology, Harvard Medical School, Boston, MA, USA
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Phuong Anh Le
- Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | - Jun Wang
- Department of Population and Public Health Sciences, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Christine Ambrosone
- Department of Cancer Prevention and Control, Roswell Park Comprehensive Cancer Center, Buffalo, NY, USA
| | - Adam Brufsky
- Department of Medicine, University of Pittsburgh Medical Center, Pittsburgh, PN, USA
| | - Fergus J Couch
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA
| | - Francesmary Modugno
- Division of Gynecologic Oncology, Department of Obstetrics, Gynecology and Reproductive Sciences, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- Department of Epidemiology, School of Public Health, University of Pittsburgh, Pittsburgh, PA, USA
- Women's Cancer Research Center, Magee-Womens Research Institute and Hillman Cancer Center, Pittsburgh, PA, USA
| | | | - Celine M Vachon
- Department of Quantitative Health Sciences, Mayo Clinic, Rochester, MN, USA
| | - Susan E Hankinson
- Channing Division of Network Medicine, Brigham and Women's Hospital, Boston, MA, USA
- Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA, USA
- Department of Biostatistics and Epidemiology, School of Public Health and Health Sciences, University of Massachusetts Amherst, Amherst, MA, USA
| | - Bernard A Rosner
- Channing Division of Network Medicine, Brigham and Women's Hospital, Boston, MA, USA
- Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA, USA
- Department of Biostatistics, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | - Rulla M Tamimi
- Department of Population Health Sciences, Weill Cornell Medical College, New York, NY, USA
| | - Cheng Peng
- Channing Division of Network Medicine, Brigham and Women's Hospital, Boston, MA, USA
| | - A Heather Eliassen
- Channing Division of Network Medicine, Brigham and Women's Hospital, Boston, MA, USA
- Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA, USA
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Martínez-Nava GA, Urbina-Jara LK, Lira-Albarrán S, Gómez HL, Ruiz-García E, Nieto-Coronel MT, Ortiz-Lopez R, Martínez Villalba KN, Muñoz-Sánchez M, Aguilar D, Gómez-Flores-Ramos L, Cabrera-Nieto SA, Mohar A, Cruz-Ramos M. Somatic Mutations in Latin American Breast Cancer Patients: A Systematic Review and Meta-Analysis. Diagnostics (Basel) 2024; 14:287. [PMID: 38337803 PMCID: PMC10855727 DOI: 10.3390/diagnostics14030287] [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: 11/30/2023] [Revised: 01/16/2024] [Accepted: 01/18/2024] [Indexed: 02/12/2024] Open
Abstract
(1) Background: Somatic mutations may be connected to the exposome, potentially playing a role in breast cancer's development and clinical outcomes. There needs to be information regarding Latin American women specifically, as they are underrepresented in clinical trials and have limited access to somatic analysis in their countries. This study aims to systematically investigate somatic mutations in breast cancer patients from Latin America to gain a better understanding of tumor biology in the region. (2) Methods: We realize a systematic review of studies on breast cancer in 21 Latin American countries using various databases such as PubMed, Google Scholar, Web of Science, RedAlyc, Dianlet, and Biblioteca Virtual en Salud. Of 392 articles that fit the criteria, 10 studies have clinical data which can be used to create a database containing clinical and genetic information. We compared mutation frequencies across different breast cancer subtypes using statistical analyses and meta-analyses of proportions. Furthermore, we identified overexpressed biological processes and canonical pathways through functional enrichment analysis. (3) Results: 342 mutations were found in six Latin American countries, with the TP53 and PIK3CA genes being the most studied mutations. The most common PIK3CA mutation was H1047R. Functional analysis provided insights into tumor biology and potential therapies. (4) Conclusion: evaluating specific somatic mutations in the Latin American population is crucial for understanding tumor biology and determining appropriate treatment options. Combining targeted therapies may improve clinical outcomes in breast cancer. Moreover, implementing healthy lifestyle strategies in Latin America could enhance therapy effectiveness and clinical outcomes.
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Affiliation(s)
- Gabriela A. Martínez-Nava
- Laboratorio de Gerociencias, Instituto Nacional de Rehabilitación Luis Guillermo Ibarra Ibarra, Calz. México-Xochimilco 289, Tlalpan, Mexico City 14389, Mexico;
| | - Laura Keren Urbina-Jara
- Tecnologico de Monterrey, Escuela de Medicina y Ciencias de la Salud, Monterrey 64710, Mexico; (L.K.U.-J.); (R.O.-L.)
| | - Saúl Lira-Albarrán
- Departamento de Gestión Académica e Investigación, Hospital Escuela, Tegucigalpa 11101, Honduras;
| | - Henry L. Gómez
- Departmento de Medicina Oncológica, Instituto Nacional de Enfermedades Neoplásicas, Av. Angamos Este 2520, Lima 15023, Peru;
| | - Erika Ruiz-García
- Laboratorio de Medicina Traslacional, Instituto Nacional de Cancerologia, Mexico City 14080, Mexico;
| | - María Tereza Nieto-Coronel
- Departamento de Medicina Oncológica, Centro Oncopalia, Universidad Mayor de San Andrés, La Paz P.O. Box 8635, Bolivia;
| | - Rocio Ortiz-Lopez
- Tecnologico de Monterrey, Escuela de Medicina y Ciencias de la Salud, Monterrey 64710, Mexico; (L.K.U.-J.); (R.O.-L.)
- Tecnologico de Monterrey, Institute for Obesity Research, Monterrey 64849, Mexico
| | - Kenia Nadiezhda Martínez Villalba
- Unidad de Epidemiología e Investigación Biomédica en Cáncer, Instituto de Investigaciones Biomédicas, UNAM-Instituto Nacional de Cancerología, Mexico City 14080, Mexico; (K.N.M.V.); (A.M.)
| | - Mariana Muñoz-Sánchez
- Facultad de Ciencias de la Salud, Universidad Anáhuac México, Mexico City 52786, Mexico; (M.M.-S.); (S.A.C.-N.)
| | - Dione Aguilar
- Tecnologico de Monterrey, Centro de Cáncer de Mama, Hospital Zambrano Hellion, San Pedro Garza García 66278, Mexico;
| | - Liliana Gómez-Flores-Ramos
- CONAHCYT/Center for Population Health Research, National Institute of Public Health, Universidad No. 655, Cuernavaca 62100, Mexico;
| | - Sara Aileen Cabrera-Nieto
- Facultad de Ciencias de la Salud, Universidad Anáhuac México, Mexico City 52786, Mexico; (M.M.-S.); (S.A.C.-N.)
| | - Alejandro Mohar
- Unidad de Epidemiología e Investigación Biomédica en Cáncer, Instituto de Investigaciones Biomédicas, UNAM-Instituto Nacional de Cancerología, Mexico City 14080, Mexico; (K.N.M.V.); (A.M.)
| | - Marlid Cruz-Ramos
- Programa Joven y Fuerte/CONAHCYT, Instituto Nacional de Cancerología, Av. San Fernando 22, Belisario Domínguez Sección 16, Tlalpan, Mexico City 14080, Mexico
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Heng YJ, Zhang KJ, Valero MG, Baker GM, Fein-Zachary VJ, Irwig MS, Wulf GM. Invasive Ductal Carcinoma of the Breast in a Transgender Man: A Case Report. Case Rep Oncol 2023; 16:811-817. [PMID: 37900827 PMCID: PMC10601725 DOI: 10.1159/000529859] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Accepted: 02/13/2023] [Indexed: 10/31/2023] Open
Abstract
There is limited literature about breast cancer in the transgender population. Very little is known about how gender-affirming hormone therapy affects their breast cancer risk. On the other end, for those diagnosed with breast cancer, there are no clinical guidelines to manage their breast cancer, specifically, how to manage their gender-affirming hormone therapy during breast cancer treatment. Here, we report a 52-year-old transman diagnosed with a grade 2 invasive ductal carcinoma (ER+/PR+/HER2-), and ductal carcinoma in situ (DCIS) of intermediate grade. We discussed his risk factors as well as treatment options.
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Affiliation(s)
- Yujing J. Heng
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Kevin J. Zhang
- Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Monica G. Valero
- Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Gabrielle M. Baker
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Valerie J. Fein-Zachary
- Department of Radiology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Michael S. Irwig
- Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Gerburg M. Wulf
- Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
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Liu Y, Gusev A, Heng YJ, Alexandrov LB, Kraft P. Somatic mutational profiles and germline polygenic risk scores in human cancer. Genome Med 2022; 14:14. [PMID: 35144655 PMCID: PMC8832866 DOI: 10.1186/s13073-022-01016-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Accepted: 01/24/2022] [Indexed: 02/03/2023] Open
Abstract
BACKGROUND The mutational profile of cancer reflects the activity of the mutagenic processes which have been operative throughout the lineage of the cancer cell. These processes leave characteristic profiles of somatic mutations called mutational signatures. Mutational signatures, including single-base substitution (SBS) signatures, may reflect the effects of exogenous or endogenous exposures. METHODS We used polygenic risk scores (PRS) to summarize common germline variation associated with cancer risk and other cancer-related traits and examined the association between somatic mutational profiles and germline PRS in 12 cancer types from The Cancer Genome Atlas. Somatic mutational profiles were constructed from whole-exome sequencing data of primary tumors. PRS were calculated for the 12 selected cancer types and 9 non-cancer traits, including cancer risk determinants, hormonal factors, and immune-mediated inflammatory diseases, using germline genetic data and published summary statistics from genome-wide association studies. RESULTS We found 17 statistically significant associations between somatic mutational profiles and germline PRS after Bonferroni correction (p < 3.15 × 10-5), including positive associations between germline inflammatory bowel disease PRS and number of somatic mutations attributed to signature SBS1 in prostate cancer and APOBEC-related signatures in breast cancer. Positive associations were also found between age at menarche PRS and mutation counts of SBS1 in overall and estrogen receptor-positive breast cancer. Consistent with prior studies that found an inverse association between the pubertal development PRS and risk of prostate cancer, likely reflecting hormone-related mechanisms, we found an inverse association between age at menarche PRS and mutation counts of SBS1 in prostate cancer. Inverse associations were also found between several cancer PRS and tumor mutation counts. CONCLUSIONS Our analysis suggests that there are robust associations between tumor somatic mutational profiles and germline PRS. These may reflect the mechanisms through hormone regulation and immune responses that contribute to cancer etiology and drive cancer progression.
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Affiliation(s)
- Yuxi Liu
- grid.38142.3c000000041936754XDepartment of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA 02115 USA ,grid.38142.3c000000041936754XProgram in Genetic Epidemiology and Statistical Genetics, Harvard T.H. Chan School of Public Health, 655 Huntington Avenue, Boston, MA 02115 USA
| | - Alexander Gusev
- grid.65499.370000 0001 2106 9910Department of Medical Oncology, Dana-Farber Cancer Institute and Harvard Medical School, Boston, MA 02215 USA
| | - Yujing J. Heng
- grid.38142.3c000000041936754XDepartment of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215 USA
| | - Ludmil B. Alexandrov
- grid.266100.30000 0001 2107 4242Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, CA 92093 USA
| | - Peter Kraft
- grid.38142.3c000000041936754XDepartment of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA 02115 USA ,grid.38142.3c000000041936754XProgram in Genetic Epidemiology and Statistical Genetics, Harvard T.H. Chan School of Public Health, 655 Huntington Avenue, Boston, MA 02115 USA ,grid.38142.3c000000041936754XDepartment of Biostatistics, Harvard T.H. Chan School of Public Health, Boston, MA 02115 USA
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5
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Su X, Feng C, Wang S, Shi L, Gu Q, Zhang H, Lan X, Zhao Y, Qiang W, Ji M, Hou P. The noncoding RNAs SNORD50A and SNORD50B-mediated TRIM21-GMPS interaction promotes the growth of p53 wild-type breast cancers by degrading p53. Cell Death Differ 2021; 28:2450-2464. [PMID: 33742136 PMCID: PMC8329294 DOI: 10.1038/s41418-021-00762-7] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2020] [Revised: 02/21/2021] [Accepted: 02/24/2021] [Indexed: 01/31/2023] Open
Abstract
Small nucleolar RNA SNORD50A and SNORD50B (SNORD50A/B) has been reported to be recurrently deleted and function as a putative tumor suppressor in different types of cancer by binding to and suppressing the activity of the KRAS oncoproteins. Its deletion correlates with poorer patient survival. However, in this study, we surprisingly found that SNORD50A/B loss predicted a better survival in breast cancer patients carrying wild-type p53. Functional studies showed that SNORD50A/B deletion strongly inhibited the proliferation, migration, invasion and tumorigenic potential, and induced cell cycle arrest and apoptosis in p53 wild-type breast cancer cells, while exerted the opposite effects in p53 mutated breast cancer cells. This was also supported by ectopically expressing SNORD50A/B in both p53 wild-type and mutated breast cancer cells. Mechanistically, SNORD50A/B clearly enhances the interaction between E3 ubiquitin ligase TRIM21 and its substrate GMPS by forming a complex among them, thereby promoting GMPS ubiquitination and its subsequent cytoplasmic sequestration. SNORD50A/B deletion in p53 wild-type breast cancer cells will release GMPS and induce the translocation of GMPS into the nucleus, where GMPS can recruit USP7 and form a complex with p53, thereby decreasing p53 ubiquitination, stabilizing p53 proteins, and inhibiting malignant phenotypes of cancer cells. Altogether, the present study first reports that SNORD50A/B plays an oncogenic role in p53 wild-type breast cancers by mediating TRIM21-GMPS interaction.
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Affiliation(s)
- Xi Su
- Key Laboratory for Tumor Precision Medicine of Shaanxi Province and Department of Endocrinology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710061, PR China
| | - Chao Feng
- Key Laboratory for Tumor Precision Medicine of Shaanxi Province and Department of Endocrinology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710061, PR China
| | - Simeng Wang
- Key Laboratory for Tumor Precision Medicine of Shaanxi Province and Department of Endocrinology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710061, PR China
| | - Liang Shi
- Key Laboratory for Tumor Precision Medicine of Shaanxi Province and Department of Endocrinology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710061, PR China
| | - Qingqing Gu
- Key Laboratory for Tumor Precision Medicine of Shaanxi Province and Department of Endocrinology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710061, PR China
| | - Haihong Zhang
- Key Laboratory for Tumor Precision Medicine of Shaanxi Province and Department of Endocrinology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710061, PR China
| | - Xinhui Lan
- Key Laboratory for Tumor Precision Medicine of Shaanxi Province and Department of Endocrinology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710061, PR China
| | - Yuelei Zhao
- Key Laboratory for Tumor Precision Medicine of Shaanxi Province and Department of Endocrinology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710061, PR China
| | - Wei Qiang
- Key Laboratory for Tumor Precision Medicine of Shaanxi Province and Department of Endocrinology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710061, PR China
| | - Meiju Ji
- Center for Translational Medicine, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710061, PR China.
| | - Peng Hou
- Key Laboratory for Tumor Precision Medicine of Shaanxi Province and Department of Endocrinology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710061, PR China.
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Unravelling roles of error-prone DNA polymerases in shaping cancer genomes. Oncogene 2021; 40:6549-6565. [PMID: 34663880 PMCID: PMC8639439 DOI: 10.1038/s41388-021-02032-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Revised: 09/01/2021] [Accepted: 09/20/2021] [Indexed: 12/12/2022]
Abstract
Mutagenesis is a key hallmark and enabling characteristic of cancer cells, yet the diverse underlying mutagenic mechanisms that shape cancer genomes are not understood. This review will consider the emerging challenge of determining how DNA damage response pathways-both tolerance and repair-act upon specific forms of DNA damage to generate mutations characteristic of tumors. DNA polymerases are typically the ultimate mutagenic effectors of DNA repair pathways. Therefore, understanding the contributions of DNA polymerases is critical to develop a more comprehensive picture of mutagenic mechanisms in tumors. Selection of an appropriate DNA polymerase-whether error-free or error-prone-for a particular DNA template is critical to the maintenance of genome stability. We review different modes of DNA polymerase dysregulation including mutation, polymorphism, and over-expression of the polymerases themselves or their associated activators. Based upon recent findings connecting DNA polymerases with specific mechanisms of mutagenesis, we propose that compensation for DNA repair defects by error-prone polymerases may be a general paradigm molding the mutational landscape of cancer cells. Notably, we demonstrate that correlation of error-prone polymerase expression with mutation burden in a subset of patient tumors from The Cancer Genome Atlas can identify mechanistic hypotheses for further testing. We contrast experimental approaches from broad, genome-wide strategies to approaches with a narrower focus on a few hundred base pairs of DNA. In addition, we consider recent developments in computational annotation of patient tumor data to identify patterns of mutagenesis. Finally, we discuss the innovations and future experiments that will develop a more comprehensive portrait of mutagenic mechanisms in human tumors.
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