51
|
Sanoguera-Miralles L, Valenzuela-Palomo A, Bueno-Martínez E, Llovet P, Díez-Gómez B, Caloca MJ, Pérez-Segura P, Fraile-Bethencourt E, Colmena M, Carvalho S, Allen J, Easton DF, Devilee P, Vreeswijk MPG, de la Hoya M, Velasco EA. Comprehensive Functional Characterization and Clinical Interpretation of 20 Splice-Site Variants of the RAD51C Gene. Cancers (Basel) 2020; 12:E3771. [PMID: 33333735 PMCID: PMC7765170 DOI: 10.3390/cancers12123771] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 12/08/2020] [Accepted: 12/09/2020] [Indexed: 12/12/2022] Open
Abstract
Hereditary breast and/or ovarian cancer is a highly heterogeneous disease with more than 10 known disease-associated genes. In the framework of the BRIDGES project (Breast Cancer Risk after Diagnostic Gene Sequencing), the RAD51C gene has been sequenced in 60,466 breast cancer patients and 53,461 controls. We aimed at functionally characterizing all the identified genetic variants that are predicted to disrupt the splicing process. Forty RAD51C variants of the intron-exon boundaries were bioinformatically analyzed, 20 of which were selected for splicing functional assays. To test them, a splicing reporter minigene with exons 2 to 8 was designed and constructed. This minigene generated a full-length transcript of the expected size (1062 nucleotides), sequence, and structure (Vector exon V1- RAD51C exons_2-8- Vector exon V2). The 20 candidate variants were genetically engineered into the wild type minigene and functionally assayed in MCF-7 cells. Nineteen variants (95%) impaired splicing, while 18 of them produced severe splicing anomalies. At least 35 transcripts were generated by the mutant minigenes: 16 protein-truncating, 6 in-frame, and 13 minor uncharacterized isoforms. According to ACMG/AMP-based standards, 15 variants could be classified as pathogenic or likely pathogenic variants: c.404G > A, c.405-6T > A, c.571 + 4A > G, c.571 + 5G > A, c.572-1G > T, c.705G > T, c.706-2A > C, c.706-2A > G, c.837 + 2T > C, c.905-3C > G, c.905-2A > C, c.905-2_905-1del, c.965 + 5G > A, c.1026 + 5_1026 + 7del, and c.1026 + 5G > T.
Collapse
Affiliation(s)
- Lara Sanoguera-Miralles
- Splicing and Genetic Susceptibility to Cancer, Instituto de Biología y Genética Molecular, Consejo Superior de Investigaciones Científicas (CSIC-UVa), 47003 Valladolid, Spain; (L.S.-M.); (A.V.-P.); (E.B.-M.); (B.D.-G.); (E.F.-B.)
| | - Alberto Valenzuela-Palomo
- Splicing and Genetic Susceptibility to Cancer, Instituto de Biología y Genética Molecular, Consejo Superior de Investigaciones Científicas (CSIC-UVa), 47003 Valladolid, Spain; (L.S.-M.); (A.V.-P.); (E.B.-M.); (B.D.-G.); (E.F.-B.)
| | - Elena Bueno-Martínez
- Splicing and Genetic Susceptibility to Cancer, Instituto de Biología y Genética Molecular, Consejo Superior de Investigaciones Científicas (CSIC-UVa), 47003 Valladolid, Spain; (L.S.-M.); (A.V.-P.); (E.B.-M.); (B.D.-G.); (E.F.-B.)
| | - Patricia Llovet
- Molecular Oncology Laboratory CIBERONC, Hospital Clinico San Carlos, IdISSC (Instituto de Investigación Sanitaria del Hospital Clínico San Carlos), 28040 Madrid, Spain; (P.L.); (P.P.-S.); (M.C.)
| | - Beatriz Díez-Gómez
- Splicing and Genetic Susceptibility to Cancer, Instituto de Biología y Genética Molecular, Consejo Superior de Investigaciones Científicas (CSIC-UVa), 47003 Valladolid, Spain; (L.S.-M.); (A.V.-P.); (E.B.-M.); (B.D.-G.); (E.F.-B.)
| | - María José Caloca
- Instituto de Biología y Genética Molecular, Consejo Superior de Investigaciones Científicas (CSIC-UVa), 47003 Valladolid, Spain;
| | - Pedro Pérez-Segura
- Molecular Oncology Laboratory CIBERONC, Hospital Clinico San Carlos, IdISSC (Instituto de Investigación Sanitaria del Hospital Clínico San Carlos), 28040 Madrid, Spain; (P.L.); (P.P.-S.); (M.C.)
| | - Eugenia Fraile-Bethencourt
- Splicing and Genetic Susceptibility to Cancer, Instituto de Biología y Genética Molecular, Consejo Superior de Investigaciones Científicas (CSIC-UVa), 47003 Valladolid, Spain; (L.S.-M.); (A.V.-P.); (E.B.-M.); (B.D.-G.); (E.F.-B.)
- Knight Cancer Research Building, 2720 S Moody Ave, Portland, OR 97201, USA
| | - Marta Colmena
- Molecular Oncology Laboratory CIBERONC, Hospital Clinico San Carlos, IdISSC (Instituto de Investigación Sanitaria del Hospital Clínico San Carlos), 28040 Madrid, Spain; (P.L.); (P.P.-S.); (M.C.)
| | - Sara Carvalho
- Centre for Cancer Genetic Epidemiology, Department of Public Health and Primary Care, University of Cambridge, Cambridge CB1 8RN, UK; (S.C.); (J.A.); (D.F.E.)
| | - Jamie Allen
- Centre for Cancer Genetic Epidemiology, Department of Public Health and Primary Care, University of Cambridge, Cambridge CB1 8RN, UK; (S.C.); (J.A.); (D.F.E.)
| | - Douglas F. Easton
- Centre for Cancer Genetic Epidemiology, Department of Public Health and Primary Care, University of Cambridge, Cambridge CB1 8RN, UK; (S.C.); (J.A.); (D.F.E.)
| | - Peter Devilee
- Leiden University Medical Center, Department of Human Genetics, 2300RC Leiden, The Netherlands; (P.D.); (M.P.G.V.)
| | - Maaike P. G. Vreeswijk
- Leiden University Medical Center, Department of Human Genetics, 2300RC Leiden, The Netherlands; (P.D.); (M.P.G.V.)
| | - Miguel de la Hoya
- Molecular Oncology Laboratory CIBERONC, Hospital Clinico San Carlos, IdISSC (Instituto de Investigación Sanitaria del Hospital Clínico San Carlos), 28040 Madrid, Spain; (P.L.); (P.P.-S.); (M.C.)
| | - Eladio A. Velasco
- Splicing and Genetic Susceptibility to Cancer, Instituto de Biología y Genética Molecular, Consejo Superior de Investigaciones Científicas (CSIC-UVa), 47003 Valladolid, Spain; (L.S.-M.); (A.V.-P.); (E.B.-M.); (B.D.-G.); (E.F.-B.)
| |
Collapse
|
52
|
Owiti NA, Nagel ZD, Engelward BP. Fluorescence Sheds Light on DNA Damage, DNA Repair, and Mutations. Trends Cancer 2020; 7:240-248. [PMID: 33203608 DOI: 10.1016/j.trecan.2020.10.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2020] [Revised: 10/09/2020] [Accepted: 10/15/2020] [Indexed: 12/17/2022]
Abstract
DNA damage can lead to carcinogenic mutations and toxicity that promotes diseases. Therefore, having rapid assays to quantify DNA damage, DNA repair, mutations, and cytotoxicity is broadly relevant to health. For example, DNA damage assays can be used to screen chemicals for genotoxicity, and knowledge about DNA repair capacity has applications in precision prevention and in personalized medicine. Furthermore, knowledge of mutation frequency has predictive power for downstream cancer, and assays for cytotoxicity can predict deleterious health effects. Tests for all of these purposes have been rendered faster and more effective via adoption of fluorescent readouts. Here, we provide an overview of established and emerging cell-based assays that exploit fluorescence for studies of DNA damage and its consequences.
Collapse
Affiliation(s)
- Norah A Owiti
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Zachary D Nagel
- Department of Environmental Health, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | - Bevin P Engelward
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA.
| |
Collapse
|
53
|
Martín-Morales L, Garre P, Lorca V, Cazorla M, Llovet P, Bando I, García-Barberan V, González-Morales ML, Esteban-Jurado C, de la Hoya M, Castellví-Bel S, Caldés T. BRIP1, a Gene Potentially Implicated in Familial Colorectal Cancer Type X. Cancer Prev Res (Phila) 2020; 14:185-194. [PMID: 33115781 DOI: 10.1158/1940-6207.capr-20-0316] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Revised: 08/17/2020] [Accepted: 10/15/2020] [Indexed: 11/16/2022]
Abstract
Familial colorectal cancer Type X (FCCTX) comprises a heterogeneous group of families with an increased risk of developing colorectal cancer and other related tumors, but with mismatch repair-proficient, microsatellite-stable (MSS) tumors. Unfortunately, the genetic basis underlying their cancer predisposition remains unknown. Although pathogenic germline variants in BRIP1 increase the risk of developing hereditary ovarian cancer, the involvement of BRIP1 in hereditary colorectal cancer is still not well known. In order to identify new BRIP1 variants associated with inherited colorectal cancer, affected and nonaffected individuals from 18 FCCTX or high-risk MSS colorectal cancer families were evaluated by whole-exome sequencing, and another 62 colorectal cancer patients from FCCTX or high-risk MSS colorectal cancer families were screened by a next-generation sequencing (NGS) multigene panel. The families were recruited at the Genetic Counseling Unit of Hospital Clínico San Carlos of Madrid. A total of three different BRIP1 mutations in three unrelated families were identified. Among them, there were two frameshift variants [c.1702_1703del, p.(Asn568TrpfsTer9) and c.903del, p.(Leu301PhefsTer2)] that result in the truncation of the protein and are thus classified as pathogenic (class 5). The remaining was a missense variant [c.2220G>T, p.(Gln740His)] considered a variant of uncertain significance (class 3). The segregation and loss-of-heterozygosity studies provide evidence linking the two BRIP1 frameshift variants to colorectal cancer risk, with suggestive but not definitive evidence that the third variant may be benign. The results here presented suggest that germline BRIP1 pathogenic variants could be associated with hereditary colorectal cancer predisposition.Prevention Relevance: We suggest that BRIP1 pathogenic germline variants may have a causal role in CRC as moderate cancer susceptibility alleles and be associated with hereditary CRC predisposition. A better understanding of hereditary CRC may provide important clues to disease predisposition and could contribute to molecular diagnostics, improved risk stratification, and targeted therapeutic strategies.
Collapse
Affiliation(s)
- Lorena Martín-Morales
- Molecular Oncology Laboratory, Hospital Clínico San Carlos, IdISSC, Centro de Investigación Biomédica en Red de Oncología (CIBERONC), Madrid, Spain
| | - Pilar Garre
- Molecular Oncology Laboratory, Hospital Clínico San Carlos, IdISSC, Centro de Investigación Biomédica en Red de Oncología (CIBERONC), Madrid, Spain
| | - Víctor Lorca
- Molecular Oncology Laboratory, Hospital Clínico San Carlos, IdISSC, Centro de Investigación Biomédica en Red de Oncología (CIBERONC), Madrid, Spain
| | - Marta Cazorla
- Molecular Oncology Laboratory, Hospital Clínico San Carlos, IdISSC, Centro de Investigación Biomédica en Red de Oncología (CIBERONC), Madrid, Spain
| | - Patricia Llovet
- Molecular Oncology Laboratory, Hospital Clínico San Carlos, IdISSC, Centro de Investigación Biomédica en Red de Oncología (CIBERONC), Madrid, Spain
| | - Inmaculada Bando
- Molecular Oncology Laboratory, Hospital Clínico San Carlos, IdISSC, Centro de Investigación Biomédica en Red de Oncología (CIBERONC), Madrid, Spain
| | - Vanesa García-Barberan
- Molecular Oncology Laboratory, Hospital Clínico San Carlos, IdISSC, Centro de Investigación Biomédica en Red de Oncología (CIBERONC), Madrid, Spain
| | | | - Clara Esteban-Jurado
- Gastroenterology Department, Hospital Clínic, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBEREHD), Barcelona, Spain
| | - Miguel de la Hoya
- Molecular Oncology Laboratory, Hospital Clínico San Carlos, IdISSC, Centro de Investigación Biomédica en Red de Oncología (CIBERONC), Madrid, Spain
| | - Sergi Castellví-Bel
- Gastroenterology Department, Hospital Clínic, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBEREHD), Barcelona, Spain
| | - Trinidad Caldés
- Molecular Oncology Laboratory, Hospital Clínico San Carlos, IdISSC, Centro de Investigación Biomédica en Red de Oncología (CIBERONC), Madrid, Spain.
| |
Collapse
|
54
|
Pavanello M, Chan IHY, Ariff A, Pharoah PDP, Gayther SA, Ramus SJ. Rare Germline Genetic Variants and the Risks of Epithelial Ovarian Cancer. Cancers (Basel) 2020; 12:E3046. [PMID: 33086730 PMCID: PMC7589980 DOI: 10.3390/cancers12103046] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Revised: 10/12/2020] [Accepted: 10/14/2020] [Indexed: 02/06/2023] Open
Abstract
A family history of ovarian or breast cancer is the strongest risk factor for epithelial ovarian cancer (EOC). Germline deleterious variants in the BRCA1 and BRCA2 genes confer EOC risks by age 80, of 44% and 17% respectively. The mismatch repair genes, particularly MSH2 and MSH6, are also EOC susceptibility genes. Several other DNA repair genes, BRIP1, RAD51C, RAD51D, and PALB2, have been identified as moderate risk EOC genes. EOC has five main histotypes; high-grade serous (HGS), low-grade serous (LGS), clear cell (CCC), endometrioid (END), and mucinous (MUC). This review examines the current understanding of the contribution of rare genetic variants to EOC, focussing on providing frequency data for each histotype. We provide an overview of frequency and risk for pathogenic variants in the known susceptibility genes as well as other proposed genes. We also describe the progress to-date to understand the role of missense variants and the different breast and ovarian cancer risks for each gene. Identification of susceptibility genes have clinical impact by reducing disease-associated mortality through improving risk prediction, with the possibility of prevention strategies, and developing new targeted treatments and these clinical implications are also discussed.
Collapse
Affiliation(s)
- Marina Pavanello
- School of Women’s and Children’s Health, Faculty of Medicine, University of New South Wales, Sydney 2052, Australia; (M.P.); (I.H.C.); (A.A.)
- Adult Cancer Program, Lowy Cancer Research Centre, University of New South Wales, Sydney 2052, Australia
| | - Isaac HY Chan
- School of Women’s and Children’s Health, Faculty of Medicine, University of New South Wales, Sydney 2052, Australia; (M.P.); (I.H.C.); (A.A.)
| | - Amir Ariff
- School of Women’s and Children’s Health, Faculty of Medicine, University of New South Wales, Sydney 2052, Australia; (M.P.); (I.H.C.); (A.A.)
- Adult Cancer Program, Lowy Cancer Research Centre, University of New South Wales, Sydney 2052, Australia
| | - Paul DP Pharoah
- Strangeways Research Laboratory, University of Cambridge, Cambridge CB1 8RN, UK;
| | - Simon A. Gayther
- Center for Cancer Prevention and Translational Genomics, Cedars Sinai Medical Center, Los Angeles, CA 90048, USA;
- Applied Genomics, Computation and Translational Core, Cedars Sinai Medical Center, Los Angeles, CA 90048, USA
| | - Susan J. Ramus
- School of Women’s and Children’s Health, Faculty of Medicine, University of New South Wales, Sydney 2052, Australia; (M.P.); (I.H.C.); (A.A.)
- Adult Cancer Program, Lowy Cancer Research Centre, University of New South Wales, Sydney 2052, Australia
| |
Collapse
|