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Grigore LG, Radoi VE, Serban A, Mihai AD, Stoica I. The Molecular Detection of Germline Mutations in the BRCA1 and BRCA2 Genes Associated with Breast and Ovarian Cancer in a Romanian Cohort of 616 Patients. Curr Issues Mol Biol 2024; 46:4630-4645. [PMID: 38785549 PMCID: PMC11119367 DOI: 10.3390/cimb46050281] [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: 04/15/2024] [Revised: 05/07/2024] [Accepted: 05/10/2024] [Indexed: 05/25/2024] Open
Abstract
The objective of this study was to identify and classify the spectrum of mutations found in the BRCA1 and BRCA2 genes associated with breast and ovarian cancer in female patients in Romania. Germline BRCA1 and BRCA2 mutations were investigated in a cohort of 616 female patients using NGS and/or MLPA methods followed by software-based data analysis and classification according to international guidelines. Out of the 616 female patients included in this study, we found that 482 patients (78.2%) did not have any mutation present in the two genes investigated; 69 patients (11.2%) had a BRCA1 mutation, 34 (5.5%) had a BRCA2 mutation, and 31 (5%) presented different type of mutations with uncertain clinical significance, moderate risk or a large mutation in the BRCA1 gene. Our investigation indicates the most common mutations in the BRCA1 and BRCA2 genes, associated with breast and ovarian cancer in the Romanian population. Our results also bring more data in support of the frequency of the c.5266 mutation in the BRCA1 gene, acknowledged in the literature as a founder mutation in Eastern Europe. We consider that the results of our study will provide necessary data regarding BRCA1 and BRCA2 mutations that would help to create a genetic database for the Romanian population.
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Affiliation(s)
- Liliana-Georgiana Grigore
- Doctoral School of Biology, Faculty of Biology, University of Bucharest, 030018 Bucharest, Romania
- Personal Genetics, 010987 Bucharest, Romania
| | - Viorica-Elena Radoi
- Department of Medical Genetics, “Carol Davila” University of Medicine and Pharmacy, 020021 Bucharest, Romania
- “Alessandrescu-Rusescu” National Institute for Maternal and Child Health, 20382 Bucharest, Romania
| | | | | | - Ileana Stoica
- Department of Genetics, Faculty of Biology, University of Bucharest, 030018 Bucharest, Romania
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2
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Guo Q, Ji S, Takeuchi K, Urasaki W, Suzuki A, Iwasaki Y, Saito H, Xu Z, Arai M, Nakamura S, Momozawa Y, Chiba N, Miki Y, Matsuura M, Sunada S. Functional evaluation of BRCA1/2 variants of unknown significance with homologous recombination assay and integrative in silico prediction model. J Hum Genet 2023; 68:849-857. [PMID: 37731132 DOI: 10.1038/s10038-023-01194-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2022] [Revised: 08/01/2023] [Accepted: 08/29/2023] [Indexed: 09/22/2023]
Abstract
Numerous variants of unknown significance (VUSs) exist in hereditary breast and ovarian cancers. Although multiple methods have been developed to assess the significance of BRCA1/2 variants, functional discrepancies among these approaches remain. Therefore, a comprehensive functional evaluation system for these variants should be established. We performed conventional homologous recombination (HR) assays for 50 BRCA1 and 108 BRCA2 VUSs and complementarily predicted VUSs using a statistical logistic regression prediction model that integrated six in silico functional prediction tools. BRCA1/2 VUSs were classified according to the results of the integrative in vitro and in silico analyses. Using HR assays, we identified 10 BRCA1 and 4 BRCA2 VUSs as low-functional pathogenic variants. For in silico prediction, the statistical prediction model showed high accuracy for both BRCA1 and BRCA2 compared with each in silico prediction tool individually and predicted nine BRCA1 and seven BRCA2 variants to be pathogenic. Integrative functional evaluation in this study and the American College of Medical Genetics and Genomics and the Association for Molecular Pathology (ACMG/AMP) guidelines strongly suggested that seven BRCA1 variants (p.Glu272Gly, p.Lys1095Glu, p.Val1653Leu, p.Thr1681Pro, p.Phe1761Val, p.Thr1773Ile, and p.Gly1803Ser) and four BRCA2 variants (p.Trp31Gly, p.Ser2616Phe, p.Tyr2660Cys, and p.Leu2792Arg) were pathogenic. This study demonstrates that integrative evaluation using conventional HR assays and optimized in silico prediction comprehensively classified the significance of BRCA VUSs for future clinical applications.
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Affiliation(s)
- Qianqian Guo
- Department of Molecular Genetics, Medical Research Institute, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan
| | - Shuting Ji
- Department of Molecular Genetics, Medical Research Institute, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan
| | - Kazuma Takeuchi
- Graduate School of Public Health, Teikyo University, 2-11-1 Kaga, Itabashi-ku, Tokyo, 173-8605, Japan
| | - Wataru Urasaki
- Department of Information Sciences, Tokyo University of Science, 2641 Yamazaki, Noda City, Chiba, 278-8510, Japan
| | - Asuka Suzuki
- Graduate School of Public Health, Teikyo University, 2-11-1 Kaga, Itabashi-ku, Tokyo, 173-8605, Japan
| | - Yusuke Iwasaki
- Laboratory for Genotyping Development, RIKEN Center for Integrative Medical Sciences, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama City, Kanagawa, 230-0045, Japan
| | - Hiroko Saito
- Department of Genetic Diagnosis, The Cancer Institute, Japanese Foundation for Cancer Research, 3-8-31 Ariake, Koto-ku, Tokyo, 135-8550, Japan
| | - Zeyu Xu
- Department of Molecular Genetics, Medical Research Institute, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan
| | - Masami Arai
- Department of Clinical Genetics, Juntendo University, Graduate School of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan
| | - Seigo Nakamura
- Division of Breast Surgical Oncology, Department of Surgery, Showa University School of Medicine, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo, 142-8555, Japan
| | - Yukihide Momozawa
- Laboratory for Genotyping Development, RIKEN Center for Integrative Medical Sciences, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama City, Kanagawa, 230-0045, Japan
| | - Natsuko Chiba
- Department of Cancer Biology; Institute of Development, Aging and Cancer, Tohoku University, 4-1 Seiryomachi, Aoba-ku, Sendai, 980-8575, Japan
| | - Yoshio Miki
- Department of Molecular Genetics, Medical Research Institute, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan.
- Department of Genetic Diagnosis, The Cancer Institute, Japanese Foundation for Cancer Research, 3-8-31 Ariake, Koto-ku, Tokyo, 135-8550, Japan.
| | - Masaaki Matsuura
- Graduate School of Public Health, Teikyo University, 2-11-1 Kaga, Itabashi-ku, Tokyo, 173-8605, Japan.
| | - Shigeaki Sunada
- Department of Molecular Genetics, Medical Research Institute, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan.
- Juntendo Advanced Research Institute for Health Science, Juntendo University, 2-1-1 Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan.
- Department of Oncology, School of Medicine, Juntendo University School of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan.
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Rein HL, Bernstein KA. Finding significance: New perspectives in variant classification of the RAD51 regulators, BRCA2 and beyond. DNA Repair (Amst) 2023; 130:103563. [PMID: 37651978 PMCID: PMC10529980 DOI: 10.1016/j.dnarep.2023.103563] [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: 04/25/2023] [Revised: 08/11/2023] [Accepted: 08/15/2023] [Indexed: 09/02/2023]
Abstract
For many individuals harboring a variant of uncertain functional significance (VUS) in a homologous recombination (HR) gene, their risk of developing breast and ovarian cancer is unknown. Integral to the process of HR are BRCA1 and regulators of the central HR protein, RAD51, including BRCA2, PALB2, RAD51C and RAD51D. Due to advancements in sequencing technology and the continued expansion of cancer screening panels, the number of VUS identified in these genes has risen significantly. Standard practices for variant classification utilize different types of predictive, population, phenotypic, allelic and functional evidence. While variant analysis is improving, there remains a struggle to keep up with demand. Understanding the effects of an HR variant can aid in preventative care and is critical for developing an effective cancer treatment plan. In this review, we discuss current perspectives in the classification of variants in the breast and ovarian cancer genes BRCA1, BRCA2, PALB2, RAD51C and RAD51D.
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Affiliation(s)
- Hayley L Rein
- University of Pittsburgh, School of Medicine, Department of Pharmacology and Chemical Biology, Pittsburgh, PA, USA
| | - Kara A Bernstein
- University of Pennsylvania School of Medicine, Department of Biochemistry and Biophysics, 421 Curie Boulevard, Philadelphia, PA, USA.
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Sahu S, Sullivan TL, Mitrophanov AY, Galloux M, Nousome D, Southon E, Caylor D, Mishra AP, Evans CN, Clapp ME, Burkett S, Malys T, Chari R, Biswas K, Sharan SK. Saturation genome editing of 11 codons and exon 13 of BRCA2 coupled with chemotherapeutic drug response accurately determines pathogenicity of variants. PLoS Genet 2023; 19:e1010940. [PMID: 37713444 PMCID: PMC10529611 DOI: 10.1371/journal.pgen.1010940] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Revised: 09/27/2023] [Accepted: 08/28/2023] [Indexed: 09/17/2023] Open
Abstract
The unknown pathogenicity of a significant number of variants found in cancer-related genes is attributed to limited epidemiological data, resulting in their classification as variant of uncertain significance (VUS). To date, Breast Cancer gene-2 (BRCA2) has the highest number of VUSs, which has necessitated the development of several robust functional assays to determine their functional significance. Here we report the use of a humanized-mouse embryonic stem cell (mESC) line expressing a single copy of the human BRCA2 for a CRISPR-Cas9-based high-throughput functional assay. As a proof-of-principle, we have saturated 11 codons encoded by BRCA2 exons 3, 18, 19 and all possible single-nucleotide variants in exon 13 and multiplexed these variants for their functional categorization. Specifically, we used a pool of 180-mer single-stranded donor DNA to generate all possible combination of variants. Using a high throughput sequencing-based approach, we show a significant drop in the frequency of non-functional variants, whereas functional variants are enriched in the pool of the cells. We further demonstrate the response of these variants to the DNA-damaging agents, cisplatin and olaparib, allowing us to use cellular survival and drug response as parameters for variant classification. Using this approach, we have categorized 599 BRCA2 variants including 93-single nucleotide variants (SNVs) across the 11 codons, of which 28 are reported in ClinVar. We also functionally categorized 252 SNVs from exon 13 into 188 functional and 60 non-functional variants, demonstrating that saturation genome editing (SGE) coupled with drug sensitivity assays can enhance functional annotation of BRCA2 VUS.
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Affiliation(s)
- Sounak Sahu
- Mouse Cancer Genetics Program, Center for Cancer Research, National Cancer Institute, Frederick, Maryland, United States of America
| | - Teresa L. Sullivan
- Mouse Cancer Genetics Program, Center for Cancer Research, National Cancer Institute, Frederick, Maryland, United States of America
| | - Alexander Y. Mitrophanov
- Statistical Consulting and Scientific Programming, Frederick National Laboratory for Cancer Research, National Institutes of Health, Frederick, Maryland, United States of America
| | | | - Darryl Nousome
- CCR Bioinformatics Resource, Leidos Biomedical Sciences, Inc. Frederick National Laboratory for Cancer Research, Frederick, Maryland, United States of America
| | - Eileen Southon
- Mouse Cancer Genetics Program, Center for Cancer Research, National Cancer Institute, Frederick, Maryland, United States of America
| | - Dylan Caylor
- Mouse Cancer Genetics Program, Center for Cancer Research, National Cancer Institute, Frederick, Maryland, United States of America
| | - Arun Prakash Mishra
- Mouse Cancer Genetics Program, Center for Cancer Research, National Cancer Institute, Frederick, Maryland, United States of America
| | - Christine N. Evans
- Genome Modification Core, Laboratory Animal Sciences Program, Frederick National Laboratory for Cancer Research, Frederick, Maryland, United States of America
| | - Michelle E. Clapp
- Genome Modification Core, Laboratory Animal Sciences Program, Frederick National Laboratory for Cancer Research, Frederick, Maryland, United States of America
| | - Sandra Burkett
- Mouse Cancer Genetics Program, Center for Cancer Research, National Cancer Institute, Frederick, Maryland, United States of America
| | - Tyler Malys
- Statistical Consulting and Scientific Programming, Frederick National Laboratory for Cancer Research, National Institutes of Health, Frederick, Maryland, United States of America
| | - Raj Chari
- Genome Modification Core, Laboratory Animal Sciences Program, Frederick National Laboratory for Cancer Research, Frederick, Maryland, United States of America
| | - Kajal Biswas
- Mouse Cancer Genetics Program, Center for Cancer Research, National Cancer Institute, Frederick, Maryland, United States of America
| | - Shyam K. Sharan
- Mouse Cancer Genetics Program, Center for Cancer Research, National Cancer Institute, Frederick, Maryland, United States of America
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Sachsenweger J, Jansche R, Merk T, Heitmeir B, Deniz M, Faust U, Roggia C, Tzschach A, Schroeder C, Riess A, Pospiech H, Peltoketo H, Pylkäs K, Winqvist R, Wiesmüller L. ABRAXAS1 orchestrates BRCA1 activities to counter genome destabilizing repair pathways-lessons from breast cancer patients. Cell Death Dis 2023; 14:328. [PMID: 37198153 DOI: 10.1038/s41419-023-05845-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Revised: 04/27/2023] [Accepted: 05/02/2023] [Indexed: 05/19/2023]
Abstract
It has been well-established that mutations in BRCA1 and BRCA2, compromising functions in DNA double-strand break repair (DSBR), confer hereditary breast and ovarian cancer risk. Importantly, mutations in these genes explain only a minor fraction of the hereditary risk and of the subset of DSBR deficient tumors. Our screening efforts identified two truncating germline mutations in the gene encoding the BRCA1 complex partner ABRAXAS1 in German early-onset breast cancer patients. To unravel the molecular mechanisms triggering carcinogenesis in these carriers of heterozygous mutations, we examined DSBR functions in patient-derived lymphoblastoid cells (LCLs) and in genetically manipulated mammary epithelial cells. By use of these strategies we were able to demonstrate that these truncating ABRAXAS1 mutations exerted dominant effects on BRCA1 functions. Interestingly, we did not observe haploinsufficiency regarding homologous recombination (HR) proficiency (reporter assay, RAD51-foci, PARP-inhibitor sensitivity) in mutation carriers. However, the balance was shifted to use of mutagenic DSBR-pathways. The dominant effect of truncated ABRAXAS1 devoid of the C-terminal BRCA1 binding site can be explained by retention of the N-terminal interaction sites for other BRCA1-A complex partners like RAP80. In this case BRCA1 was channeled from the BRCA1-A to the BRCA1-C complex, which induced single-strand annealing (SSA). Further truncation, additionally deleting the coiled-coil region of ABRAXAS1, unleashed excessive DNA damage responses (DDRs) de-repressing multiple DSBR-pathways including SSA and non-homologous end-joining (NHEJ). Our data reveal de-repression of low-fidelity repair activities as a common feature of cells from patients with heterozygous mutations in genes encoding BRCA1 and its complex partners.
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Affiliation(s)
- Juliane Sachsenweger
- Department of Obstetrics and Gynecology, Ulm University, Ulm, Germany
- Laboratory of Cancer Genetics and Tumor Biology, Translational Medicine Research Unit, Biocenter Oulu, University of Oulu, Oulu, Finland
| | - Rebecca Jansche
- Department of Obstetrics and Gynecology, Ulm University, Ulm, Germany
| | - Tatjana Merk
- Department of Obstetrics and Gynecology, Ulm University, Ulm, Germany
| | - Benedikt Heitmeir
- Department of Obstetrics and Gynecology, Ulm University, Ulm, Germany
| | - Miriam Deniz
- Department of Obstetrics and Gynecology, Ulm University, Ulm, Germany
| | - Ulrike Faust
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany
| | - Cristiana Roggia
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany
| | - Andreas Tzschach
- Institute of Human Genetics, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Christopher Schroeder
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany
| | - Angelika Riess
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany
| | - Helmut Pospiech
- Leibniz Institute on Aging - Fritz Lipmann Institute, Jena, Germany
- Faculty of Biochemistry and Molecular Medicine, University of Oulu, Oulu, Finland
| | - Hellevi Peltoketo
- Laboratory of Cancer Genetics and Tumor Biology, Translational Medicine Research Unit, Biocenter Oulu, University of Oulu, Oulu, Finland
| | - Katri Pylkäs
- Laboratory of Cancer Genetics and Tumor Biology, Translational Medicine Research Unit, Biocenter Oulu, University of Oulu, Oulu, Finland
- Laboratory of Cancer Genetics and Tumor Biology, Northern Finland Laboratory Centre, Oulu, Finland
| | - Robert Winqvist
- Laboratory of Cancer Genetics and Tumor Biology, Translational Medicine Research Unit, Biocenter Oulu, University of Oulu, Oulu, Finland
- Laboratory of Cancer Genetics and Tumor Biology, Northern Finland Laboratory Centre, Oulu, Finland
| | - Lisa Wiesmüller
- Department of Obstetrics and Gynecology, Ulm University, Ulm, Germany.
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6
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Bassi N, Hovland HN, Rasheed K, Jarhelle E, Pedersen N, Mchaina EK, Bakkan SME, Iversen N, Høberg-Vetti H, Haukanes BI, Knappskog PM, Aukrust I, Ognedal E, Van Ghelue M. Functional analyses of rare germline BRCA1 variants by transcriptional activation and homologous recombination repair assays. BMC Cancer 2023; 23:368. [PMID: 37085799 PMCID: PMC10122298 DOI: 10.1186/s12885-023-10790-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Accepted: 03/30/2023] [Indexed: 04/23/2023] Open
Abstract
BACKGROUND Damaging alterations in the BRCA1 gene have been extensively described as one of the main causes of hereditary breast and ovarian cancer (HBOC). BRCA1 alterations can lead to impaired homologous recombination repair (HRR) of double-stranded DNA breaks, a process which involves the RING, BRCT and coiled-coil domains of the BRCA1 protein. In addition, the BRCA1 protein is involved in transcriptional activation (TA) of several genes through its C-terminal BRCT domain. METHODS In this study, we have investigated the effect on HRR and TA of 11 rare BRCA1 missense variants classified as variants of uncertain clinical significance (VUS), located within or in close proximity to the BRCT domain, with the aim of generating additional knowledge to guide the correct classification of these variants. The variants were selected from our previous study "BRCA1 Norway", which is a collection of all BRCA1 variants detected at the four medical genetic departments in Norway. RESULTS All variants, except one, showed a significantly reduced HRR activity compared to the wild type (WT) protein. Two of the variants (p.Ala1708Val and p.Trp1718Ser) also exhibited low TA activity similar to the pathogenic controls. The variant p.Trp1718Ser could be reclassified to likely pathogenic. However, for ten of the variants, the total strength of pathogenic evidence was not sufficient for reclassification according to the CanVIG-UK BRCA1/BRCA2 gene-specific guidelines for variant interpretation. CONCLUSIONS When including the newly achieved functional evidence with other available information, one VUS was reclassified to likely pathogenic. Eight of the investigated variants affected only one of the assessed activities of BRCA1, highlighting the importance of comparing results obtained from several functional assays to better understand the consequences of BRCA1 variants on protein function. This is especially important for multifunctional proteins such as BRCA1.
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Affiliation(s)
- Nicola Bassi
- Department of Medical Genetics, Division of Child and Adolescent Health, University Hospital of North Norway, Tromsø, Norway
| | - Henrikke Nilsen Hovland
- Familial Cancer Center, Haukeland University Hospital, Bergen, Norway
- Department of Medical Genetics, Haukeland University Hospital, Bergen, Norway
- Department of Clinical Science, University of Bergen, Bergen, Norway
| | - Kashif Rasheed
- Department of Medical Biology, University of Tromsø, Tromsø, Norway
- Present address: Institute for Clinical and Molecular Medicine, Norwegian University of Science and Technology, NTNU, Trondheim, Norway
| | - Elisabeth Jarhelle
- Department of Medical Genetics, Division of Child and Adolescent Health, University Hospital of North Norway, Tromsø, Norway
- Northern Norway Family Cancer Center, University Hospital of North Norway, Tromsø, Norway
| | - Nikara Pedersen
- Department of Biological Sciences, University of Bergen, Bergen, Norway
| | - Eunice Kabanyana Mchaina
- Familial Cancer Center, Haukeland University Hospital, Bergen, Norway
- Department of Medical Genetics, Haukeland University Hospital, Bergen, Norway
| | | | - Nina Iversen
- Department of Medical Genetics, Oslo University Hospital, Oslo, Norway
| | - Hildegunn Høberg-Vetti
- Familial Cancer Center, Haukeland University Hospital, Bergen, Norway
- Department of Medical Genetics, Haukeland University Hospital, Bergen, Norway
| | - Bjørn Ivar Haukanes
- Department of Medical Genetics, Haukeland University Hospital, Bergen, Norway
| | - Per Morten Knappskog
- Department of Medical Genetics, Haukeland University Hospital, Bergen, Norway
- Department of Clinical Science, University of Bergen, Bergen, Norway
| | - Ingvild Aukrust
- Department of Medical Genetics, Haukeland University Hospital, Bergen, Norway.
- Department of Clinical Science, University of Bergen, Bergen, Norway.
| | - Elisabet Ognedal
- Familial Cancer Center, Haukeland University Hospital, Bergen, Norway
- Department of Medical Genetics, Haukeland University Hospital, Bergen, Norway
| | - Marijke Van Ghelue
- Department of Medical Genetics, Division of Child and Adolescent Health, University Hospital of North Norway, Tromsø, Norway
- Northern Norway Family Cancer Center, University Hospital of North Norway, Tromsø, Norway
- Department of Clinical Medicine, University of Tromsø, Tromsø, Norway
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Functional Analyses of Rare Germline Missense BRCA1 Variants Located within and outside Protein Domains with Known Functions. Genes (Basel) 2023; 14:genes14020262. [PMID: 36833189 PMCID: PMC9957003 DOI: 10.3390/genes14020262] [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: 12/14/2022] [Revised: 01/16/2023] [Accepted: 01/17/2023] [Indexed: 01/20/2023] Open
Abstract
The BRCA1 protein is implicated in numerous important cellular processes to prevent genomic instability and tumorigenesis, and pathogenic germline variants predispose carriers to hereditary breast and ovarian cancer (HBOC). Most functional studies of missense variants in BRCA1 focus on variants located within the Really Interesting New Gene (RING), coiled-coil and BRCA1 C-terminal (BRCT) domains, and several missense variants in these regions have been shown to be pathogenic. However, the majority of these studies focus on domain specific assays, and have been performed using isolated protein domains and not the full-length BRCA1 protein. Furthermore, it has been suggested that BRCA1 missense variants located outside domains with known function are of no functional importance, and could be classified as (likely) benign. However, very little is known about the role of the regions outside the well-established domains of BRCA1, and only a few functional studies of missense variants located within these regions have been published. In this study, we have, therefore, functionally evaluated the effect of 14 rare BRCA1 missense variants considered to be of uncertain clinical significance, of which 13 are located outside the well-established domains and one within the RING domain. In order to investigate the hypothesis stating that most BRCA1 variants located outside the known protein domains are benign and of no functional importance, multiple protein assays including protein expression and stability, subcellular localisation and protein interactions have been performed, utilising the full-length protein to better mimic the native state of the protein. Two variants located outside the known domains (p.Met297Val and p.Asp1152Asn) and one variant within the RING domain (p.Leu52Phe) were found to make the BRCA1 protein more prone to proteasome-mediated degradation. In addition, two variants (p.Leu1439Phe and p.Gly890Arg) also located outside known domains were found to have reduced protein stability compared to the wild type protein. These findings indicate that variants located outside the RING, BRCT and coiled-coiled domains could also affect the BRCA1 protein function. For the nine remaining variants, no significant effects on BRCA1 protein functions were observed. Based on this, a reclassification of seven variants from VUS to likely benign could be suggested.
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8
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De Paolis E, Paris I, Tilocca B, Roncada P, Foca L, Tiberi G, D’Angelo T, Pavese F, Muratore M, Carbognin L, Garganese G, Masetti R, Di Leone A, Fabi A, Scambia G, Urbani A, Generali D, Minucci A, Santonocito C. Assessing the pathogenicity of BRCA1/2 variants of unknown significance: Relevance and challenges for breast cancer precision medicine. Front Oncol 2023; 12:1053035. [PMID: 36741700 PMCID: PMC9891372 DOI: 10.3389/fonc.2022.1053035] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2022] [Accepted: 12/28/2022] [Indexed: 01/19/2023] Open
Abstract
Introduction Breast cancer (BC) is the leading cause of cancer-related death in women worldwide. Pathogenic variants in BRCA1 and BRCA2 genes account for approximately 50% of all hereditary BC, with 60-80% of patients characterized by Triple Negative Breast Cancer (TNBC) at an early stage phenotype. The identification of a pathogenic BRCA1/2 variant has important and expanding roles in risk-reducing surgeries, treatment planning, and familial surveillance. Otherwise, finding unclassified Variants of Unknown Significance (VUS) limits the clinical utility of the molecular test, leading to an "imprecise medicine". Methods We reported the explanatory example of the BRCA1 c.5057A>C, p.(His1686Pro) VUS identified in a patient with TNBC. We integrated data from family history and clinic-pathological evaluations, genetic analyses, and bioinformatics in silico investigations to evaluate the VUS classification. Results Our evaluation posed evidences for the pathogenicity significance of the investigated VUS: 1) association of the BRCA1 variant to cancer-affected members of the family; 2) absence of another high-risk mutation; 3) multiple indirect evidences derived from gene and protein structural analysis. Discussion In line with the ongoing efforts to uncertain variants classification, we speculated about the relevance of an in-depth assessment of pathogenicity of BRCA1/2 VUS for a personalized management of patients with BC. We underlined that the efficient integration of clinical data with the widest number of supporting molecular evidences should be adopted for the proper management of patients, with the final aim of effectively guide the best prognostic and therapeutic paths.
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Affiliation(s)
- Elisa De Paolis
- Clinical Chemistry, Biochemistry and Molecular Biology Operations (UOC), Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy,Department of Basic Biotechnological Sciences, Intensivological and Perioperative Clinics, Catholic University of Sacred Heart, Rome, Italy
| | - Ida Paris
- Division of Oncological Gynecology, Department of Women’s and Children’s Health, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy,*Correspondence: Ida Paris,
| | - Bruno Tilocca
- Department of Health Science, University “Magna Graecia” of Catanzaro, Catanzaro, Italy
| | - Paola Roncada
- Department of Health Science, University “Magna Graecia” of Catanzaro, Catanzaro, Italy
| | - Laura Foca
- Clinical Chemistry, Biochemistry and Molecular Biology Operations (UOC), Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy
| | - Giordana Tiberi
- Division of Oncological Gynecology, Department of Women’s and Children’s Health, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy
| | - Tatiana D’Angelo
- Division of Oncological Gynecology, Department of Women’s and Children’s Health, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy
| | - Francesco Pavese
- Division of Oncological Gynecology, Department of Women’s and Children’s Health, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy
| | - Margherita Muratore
- Division of Oncological Gynecology, Department of Women’s and Children’s Health, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy
| | - Luisa Carbognin
- Division of Oncological Gynecology, Department of Women’s and Children’s Health, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy
| | - Giorgia Garganese
- Gynaecology and Breast Care Center, Mater Olbia Hospital, Olbia, Italy,Dipartimento Universitario Scienze della Vita e Sanità Pubblica, Sezione di Ginecologia ed Ostetricia, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Riccardo Masetti
- Division of Oncological Gynecology, Department of Women’s and Children’s Health, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy
| | - Alba Di Leone
- Division of Oncological Gynecology, Department of Women’s and Children’s Health, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy
| | - Alessandra Fabi
- Unit of Precision Medicine in Breast Cancer, Scientific Directorate, Department of Woman and Child Health and Public Health, Fondazione Policlinico Universitario A. Gemelli, IRCCS, Rome, Italy
| | - Giovanni Scambia
- Division of Oncological Gynecology, Department of Women’s and Children’s Health, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy
| | - Andrea Urbani
- Clinical Chemistry, Biochemistry and Molecular Biology Operations (UOC), Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy,Department of Basic Biotechnological Sciences, Intensivological and Perioperative Clinics, Catholic University of Sacred Heart, Rome, Italy
| | - Daniele Generali
- Department of Medical, Surgery and Health Sciences, University of Trieste, Trieste, Italy
| | - Angelo Minucci
- Departmental Unit of Molecular and Genomic Diagnostics, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy
| | - Concetta Santonocito
- Clinical Chemistry, Biochemistry and Molecular Biology Operations (UOC), Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy,Department of Basic Biotechnological Sciences, Intensivological and Perioperative Clinics, Catholic University of Sacred Heart, Rome, Italy
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9
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Caleca L, Radice P. Refinement of the assignment to the ACMG/AMP BS3 and PS3 criteria of eight BRCA1 variants of uncertain significance by integrating available functional data with protein interaction assays. Front Oncol 2023; 13:1146604. [PMID: 37168384 PMCID: PMC10164951 DOI: 10.3389/fonc.2023.1146604] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Accepted: 04/06/2023] [Indexed: 05/13/2023] Open
Abstract
The clinical screening of cancer predisposition genes has led to the identification of a large number of variants of uncertain significance (VUS). Multifactorial likelihood models that predict the odds ratio for VUS in favor or against cancer causality, have been developed, but their use is limited by the amount of necessary data, which are difficult to obtain for rare variants. The guidelines for variant interpretation of the American College of Medical Genetics and Genomics along with the Association for Molecular Pathology (ACMG/AMP) state that "well-established" functional studies provide strong support of a pathogenic or benign impact (criteria PS3 and BS3, respectively) and can be used as evidence type to reach a final classification. Moreover, the Clinical Genome Resource Sequence Variant Interpretation Working Group developed rule specifications to refine the PS3/BS3 criteria. Recently, Lira PC et al. developed the "Hi Set" approach that generated PS3/BS3 codes for over two-thousands BRCA1 VUS. While highly successful, this approach did not discriminate a group of variants with conflicting evidences. Here, we aimed to implement the outcomes of the "Hi-set" approach applying Green Fluorescent Protein (GFP)-reassembly assays, assessing the effect of variants in the RING and BRCT domains of BRCA1 on the binding of these domains with the UbcH5a or ABRAXAS proteins, respectively. The analyses of 26 clinically classified variants, including 13 tested in our previous study, showed 100% sensitivity and specificity in identifying pathogenic and benign variants for both the RING/UbcH5a and the BRCTs/ABRAXAS interactions. We derived the strength of evidences generated by the GFP-reassembly assays corresponding to moderate for both PS3 and BS3 criteria assessment. The GFP-reassembly assays were applied to the functional characterization of 8 discordant variants from the study by Lyra et al. The outcomes of these analyses, combined with those reported in the "Hi Set" study, allowed the assignment of ACMG/AMP criteria in favor or against pathogenicity for all 8 examined variants. The above findings were validated with a semi-quantitative Mammalian Two-Hybrid approach, and totally concordant results were observed. Our data contributes in shedding light on the functional significance of BRCA1 VUS and on their clinical interpretation within the ACMG/AMP framework.
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10
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Lopez-Perez G, Wijayatunge R, McCrum KB, Holmstrom SR, Mgbemena VE, Ross TS. BRCA1 and TP53 codeficiency causes a PARP inhibitor-sensitive erythroproliferative neoplasm. JCI Insight 2022; 7:158257. [PMID: 36346676 PMCID: PMC9869974 DOI: 10.1172/jci.insight.158257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Accepted: 10/28/2022] [Indexed: 11/09/2022] Open
Abstract
Mutations in the BRCA1 tumor suppressor gene, such as 5382insC (BRCA1insC), give carriers an increased risk for breast, ovarian, prostate, and pancreatic cancers. We have previously reported that, in mice, Brca1 deficiency in the hematopoietic system leads to pancytopenia and, as a result, early lethality. We explored the cellular consequences of Brca1-null and BRCA1insC alleles in combination with Trp53 deficiency in the murine hematopoietic system. We found that Brca1 and Trp53 codeficiency led to a highly penetrant erythroproliferative disorder that is characterized by hepatosplenomegaly and by expanded megakaryocyte erythroid progenitor (MEP) and immature erythroid blast populations. The expanded erythroid progenitor populations in both BM and spleen had the capacity to transmit the disease into secondary mouse recipients, suggesting that Brca1 and Trp53 codeficiency provides a murine model of hematopoietic neoplasia. This Brca1/Trp53 model replicated Poly (ADP-ribose) polymerase (PARP) inhibitor olaparib sensitivity seen in existing Brca1/Trp53 breast cancer models and had the benefits of monitoring disease progression and drug responses via peripheral blood analyses without sacrificing experimental animals. In addition, this erythroid neoplasia developed much faster than murine breast cancer, allowing for increased efficiency of future preclinical studies.
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11
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Dong B, Yang B, Chen W, Du X, Fan L, Yao X, Xue W. Olaparib for Chinese metastatic castration-resistant prostate cancer: A real-world study of efficacy and gene predictive analysis. Med Oncol 2022; 39:96. [DOI: 10.1007/s12032-022-01648-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2021] [Accepted: 01/05/2022] [Indexed: 01/18/2023]
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12
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Bellè F, Mercatanti A, Lodovichi S, Congregati C, Guglielmi C, Tancredi M, Caligo MA, Cervelli T, Galli A. Validation and Data-Integration of Yeast-Based Assays for Functional Classification of BRCA1 Missense Variants. Int J Mol Sci 2022; 23:ijms23074049. [PMID: 35409408 PMCID: PMC8999655 DOI: 10.3390/ijms23074049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 04/01/2022] [Accepted: 04/03/2022] [Indexed: 11/23/2022] Open
Abstract
Germline mutations in the BRCA1 gene have been reported to increase the lifetime risk of developing breast and/or ovarian cancer (BOC). By new sequencing technologies, numerous variants of uncertain significance (VUS) are identified. It is mandatory to develop new tools to evaluate their functional impact and pathogenicity. As the expression of pathogenic BRCA1 variants in Saccharomyces cerevisiae increases the frequency of intra- and inter-chromosomal homologous recombination (HR), and gene reversion (GR), we validated the two HR and the GR assays by testing 23 benign and 23 pathogenic variants and compared the results with those that were obtained in the small colony phenotype (SCP) assay, an additional yeast-based assay, that was validated previously. We demonstrated that they scored high accuracy, sensitivity, and sensibility. By using a classifier that was based on majority of voting, we have integrated data from HR, GR, and SCP assays and developed a reliable method, named yBRCA1, with high sensitivity to obtain an accurate VUS functional classification (benign or pathogenic). The classification of BRCA1 variants, important for assessing the risk of developing BOC, is often difficult to establish with genetic methods because they occur rarely in the population. This study provides a new tool to get insights on the functional impact of the BRCA1 variants.
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Affiliation(s)
- Francesca Bellè
- Yeast Genetics and Genomics, Laboratory of Functional Genetics and Genomics, Institute of Clinical Physiology, CNR via Moruzzi 1, 56125 Pisa, Italy; (F.B.); (A.M.); (S.L.); (T.C.)
| | - Alberto Mercatanti
- Yeast Genetics and Genomics, Laboratory of Functional Genetics and Genomics, Institute of Clinical Physiology, CNR via Moruzzi 1, 56125 Pisa, Italy; (F.B.); (A.M.); (S.L.); (T.C.)
| | - Samuele Lodovichi
- Yeast Genetics and Genomics, Laboratory of Functional Genetics and Genomics, Institute of Clinical Physiology, CNR via Moruzzi 1, 56125 Pisa, Italy; (F.B.); (A.M.); (S.L.); (T.C.)
| | - Caterina Congregati
- Division of Internal Medicine, University Hospital of Pisa, 56125 Pisa, Italy;
| | - Chiara Guglielmi
- Molecular Genetics Unit, Department of Laboratory Medicine, University Hospital of Pisa, 56125 Pisa, Italy; (C.G.); (M.T.)
| | - Mariella Tancredi
- Molecular Genetics Unit, Department of Laboratory Medicine, University Hospital of Pisa, 56125 Pisa, Italy; (C.G.); (M.T.)
| | - Maria Adelaide Caligo
- Molecular Genetics Unit, Department of Laboratory Medicine, University Hospital of Pisa, 56125 Pisa, Italy; (C.G.); (M.T.)
- Correspondence: (M.A.C.); (A.G.)
| | - Tiziana Cervelli
- Yeast Genetics and Genomics, Laboratory of Functional Genetics and Genomics, Institute of Clinical Physiology, CNR via Moruzzi 1, 56125 Pisa, Italy; (F.B.); (A.M.); (S.L.); (T.C.)
| | - Alvaro Galli
- Yeast Genetics and Genomics, Laboratory of Functional Genetics and Genomics, Institute of Clinical Physiology, CNR via Moruzzi 1, 56125 Pisa, Italy; (F.B.); (A.M.); (S.L.); (T.C.)
- Correspondence: (M.A.C.); (A.G.)
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13
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Sherker A, Chaudhary N, Adam S, Heijink AM, Noordermeer SM, Fradet-Turcotte A, Durocher D. Two redundant ubiquitin-dependent pathways of BRCA1 localization to DNA damage sites. EMBO Rep 2021; 22:e53679. [PMID: 34726323 PMCID: PMC8647010 DOI: 10.15252/embr.202153679] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Revised: 10/12/2021] [Accepted: 10/13/2021] [Indexed: 12/31/2022] Open
Abstract
The tumor suppressor BRCA1 accumulates at sites of DNA damage in a ubiquitin‐dependent manner. In this work, we revisit the role of RAP80 in promoting BRCA1 recruitment to damaged chromatin. We find that RAP80 acts redundantly with the BRCA1 RING domain to promote BRCA1 recruitment to DNA damage sites. We show that that RNF8 E3 ligase acts upstream of both the RAP80‐ and RING‐dependent activities, whereas RNF168 acts uniquely upstream of the RING domain. BRCA1 RING mutations that do not impact BARD1 interaction, such as the E2 binding‐deficient I26A mutation, render BRCA1 unable to accumulate at DNA damage sites in the absence of RAP80. Cells that combine BRCA1 I26A and mutations that disable the RAP80–BRCA1 interaction are hypersensitive to PARP inhibition and are unable to form RAD51 foci. Our results suggest that in the absence of RAP80, the BRCA1 E3 ligase activity is necessary for recognition of histone H2A Lys13/Lys15 ubiquitylation by BARD1, although we cannot rule out the possibility that the BRCA1 RING facilitates ubiquitylated nucleosome recognition in other ways.
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Affiliation(s)
- Alana Sherker
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, ON, Canada.,Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
| | - Natasha Chaudhary
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, ON, Canada
| | - Salomé Adam
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, ON, Canada
| | | | - Sylvie M Noordermeer
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, ON, Canada
| | - Amélie Fradet-Turcotte
- CHU de Québec Research Center-Université Laval (L'Hôtel-Dieu de Québec), Cancer Research Center, Québec, QC, Canada
| | - Daniel Durocher
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, ON, Canada.,Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
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14
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Alkassis S, Yazdanpanah O, Philip PA. BRCA mutations in pancreatic cancer and progress in their targeting. Expert Opin Ther Targets 2021; 25:547-557. [PMID: 34289788 DOI: 10.1080/14728222.2021.1957462] [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] [Indexed: 12/17/2022]
Abstract
Introduction: Genomic instability resulting from DNA damage repair (DDR) deficiencies is a hallmark of cancer and offers treatment opportunities. Homologous recombination DDR defect is a result of multiple critical gene mutations, including BRCA1/2. Targeting DNA DDR defects in pancreatic cancer (PC) is emerging as a potential treatment strategy with current focus on BRCA mutations.Areas covered: Challenges in treating patients with PC are explained. We review DDR defects as a treatment target in PC, specifically, germline BRCA mutation and sensitivity to platinum compounds and exploiting the strategy of synthetic lethality using poly (ADP-ribose) polymerase (PARP) inhibition. Literature review was undertaken through PubMed, Google Scholar, and Clinicaltrials.gov website.Expert opinion: DDR defects are promising targets for novel therapies in PC. Early application of such strategy is in patient subgroup with BRCA germline mutation, which is seen in only 5-7% of the PC population. The oral PARP inhibitor olaparib in the maintenance setting represents the first targeted therapy in metastatic PC based on a phase 3 study. There is a very modest benefit for patients with PC using PARP inhibitors. Future work must improve our understanding of mechanisms of sensitivity and resistance to PARP inhibitors in PC and enhance the molecular selection of patients for such therapy.
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Affiliation(s)
- Samer Alkassis
- Internal Medicine Department, Wayne State University/Detroit Medical Center, Detroit, MI, USA
| | - Omid Yazdanpanah
- Internal Medicine Department, Wayne State University/Detroit Medical Center, Detroit, MI, USA
| | - Philip Agop Philip
- Division of Hematology/Oncology, Karmanos Cancer Institute, Detroit, MI, USA
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15
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Calvo JA, Fritchman B, Hernandez D, Persky NS, Johannessen CM, Piccioni F, Kelch BA, Cantor SB. Comprehensive Mutational Analysis of the BRCA1-Associated DNA Helicase and Tumor-Suppressor FANCJ/BACH1/BRIP1. Mol Cancer Res 2021; 19:1015-1025. [PMID: 33619228 DOI: 10.1158/1541-7786.mcr-20-0828] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Revised: 01/27/2021] [Accepted: 02/18/2021] [Indexed: 12/15/2022]
Abstract
FANCJ (BRIP1/BACH1) is a hereditary breast and ovarian cancer (HBOC) gene encoding a DNA helicase. Similar to HBOC genes, BRCA1 and BRCA2, FANCJ is critical for processing DNA inter-strand crosslinks (ICL) induced by chemotherapeutics, such as cisplatin. Consequently, cells deficient in FANCJ or its catalytic activity are sensitive to ICL-inducing agents. Unfortunately, the majority of FANCJ clinical mutations remain uncharacterized, limiting therapeutic opportunities to effectively use cisplatin to treat tumors with mutated FANCJ. Here, we sought to perform a comprehensive screen to identify FANCJ loss-of-function (LOF) mutations. We developed a FANCJ lentivirus mutation library representing approximately 450 patient-derived FANCJ nonsense and missense mutations to introduce FANCJ mutants into FANCJ knockout (K/O) HeLa cells. We performed a high-throughput screen to identify FANCJ LOF mutants that, as compared with wild-type FANCJ, fail to robustly restore resistance to ICL-inducing agents, cisplatin or mitomycin C (MMC). On the basis of the failure to confer resistance to either cisplatin or MMC, we identified 26 missense and 25 nonsense LOF mutations. Nonsense mutations elucidated a relationship between location of truncation and ICL sensitivity, as the majority of nonsense mutations before amino acid 860 confer ICL sensitivity. Further validation of a subset of LOF mutations confirmed the ability of the screen to identify FANCJ mutations unable to confer ICL resistance. Finally, mapping the location of LOF mutations to a new homology model provides additional functional information. IMPLICATIONS: We identify 51 FANCJ LOF mutations, providing important classification of FANCJ mutations that will afford additional therapeutic strategies for affected patients.
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Affiliation(s)
- Jennifer A Calvo
- Department of Molecular Cell and Cancer Biology, University of Massachusetts Medical School, Worcester, Massachusetts
| | - Briana Fritchman
- The Broad Institute of MIT and Harvard, Cambridge, Massachusetts
| | | | - Nicole S Persky
- The Broad Institute of MIT and Harvard, Cambridge, Massachusetts
| | | | | | - Brian A Kelch
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, Massachusetts
| | - Sharon B Cantor
- Department of Molecular Cell and Cancer Biology, University of Massachusetts Medical School, Worcester, Massachusetts.
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16
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Hirsch S, Gieldon L, Sutter C, Dikow N, Schaaf CP. Germline testing for homologous recombination repair genes—opportunities and challenges. Genes Chromosomes Cancer 2020; 60:332-343. [DOI: 10.1002/gcc.22900] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Accepted: 09/29/2020] [Indexed: 12/21/2022] Open
Affiliation(s)
- Steffen Hirsch
- Institute of Human Genetics Heidelberg University Hospital Heidelberg Germany
- Hopp Children's Cancer Center Heidelberg (KiTZ) Heidelberg Germany
| | - Laura Gieldon
- Institute of Human Genetics Heidelberg University Hospital Heidelberg Germany
| | - Christian Sutter
- Institute of Human Genetics Heidelberg University Hospital Heidelberg Germany
| | - Nicola Dikow
- Institute of Human Genetics Heidelberg University Hospital Heidelberg Germany
| | - Christian P. Schaaf
- Institute of Human Genetics Heidelberg University Hospital Heidelberg Germany
- Department of Molecular and Human Genetics Baylor College of Medicine Houston Texas
- Jan and Dan Duncan Neurological Research Institute Texas Children's Hospital Houston Texas
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