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1.
Nat Commun ; 15(1): 4716, 2024 Jun 03.
Article in English | MEDLINE | ID: mdl-38830843

ABSTRACT

BRCA2 is a tumor suppressor protein responsible for safeguarding the cellular genome from replication stress and genotoxicity, but the specific mechanism(s) by which this is achieved to prevent early oncogenesis remains unclear. Here, we provide evidence that BRCA2 acts as a critical suppressor of head-on transcription-replication conflicts (HO-TRCs). Using Okazaki-fragment sequencing (Ok-seq) and computational analysis, we identified origins (dormant origins) that are activated near the transcription termination sites (TTS) of highly expressed, long genes in response to replication stress. Dormant origins are a source for HO-TRCs, and drug treatments that inhibit dormant origin firing led to a reduction in HO-TRCs, R-loop formation, and DNA damage. Using super-resolution microscopy, we showed that HO-TRC events track with elongating RNA polymerase II, but not with transcription initiation. Importantly, RNase H2 is recruited to sites of HO-TRCs in a BRCA2-dependent manner to help alleviate toxic R-loops associated with HO-TRCs. Collectively, our results provide a mechanistic basis for how BRCA2 shields against genomic instability by preventing HO-TRCs through both direct and indirect means occurring at predetermined genomic sites based on the pre-cancer transcriptome.


Subject(s)
BRCA2 Protein , DNA Replication , RNA Polymerase II , Ribonuclease H , Humans , BRCA2 Protein/genetics , BRCA2 Protein/metabolism , Ribonuclease H/metabolism , Ribonuclease H/genetics , RNA Polymerase II/metabolism , Transcription, Genetic , Transcription Termination, Genetic , DNA Damage , Replication Origin , R-Loop Structures , Cell Line, Tumor
2.
BMC Cancer ; 24(1): 673, 2024 Jun 03.
Article in English | MEDLINE | ID: mdl-38825709

ABSTRACT

Hepatocellular carcinoma (HCC) genomic research has discovered actionable genetic changes that might guide treatment decisions and clinical trials. Nonetheless, due to a lack of large-scale multicenter clinical validation, these putative targets have not been converted into patient survival advantages. So, it's crucial to ascertain whether genetic analysis is clinically feasible, useful, and whether it can be advantageous for patients. We sequenced tumour tissue and blood samples (as normal controls) from 111 Chinese HCC patients at Qingdao University Hospital using the 508-gene panel and the 688-gene panel, respectively. Approximately 95% of patients had gene variations related to targeted treatment, with 50% having clinically actionable mutations that offered significant information for targeted therapy. Immune cell infiltration was enhanced in individuals with TP53 mutations but decreased in patients with CTNNB1 and KMT2D mutations. More notably, we discovered that SPEN, EPPK1, and BRCA2 mutations were related to decreased median overall survival, although MUC16 mutations were not. Furthermore, we found mutant MUC16 as an independent protective factor for the prognosis of HCC patients after curative hepatectomy. In conclusion, this study connects genetic abnormalities to clinical practice and potentially identifies individuals with poor prognoses who may benefit from targeted treatment or immunotherapy.


Subject(s)
Carcinoma, Hepatocellular , Liver Neoplasms , Mutation , Humans , Liver Neoplasms/genetics , Liver Neoplasms/therapy , Liver Neoplasms/mortality , Liver Neoplasms/pathology , Carcinoma, Hepatocellular/genetics , Carcinoma, Hepatocellular/therapy , Carcinoma, Hepatocellular/mortality , Carcinoma, Hepatocellular/pathology , Male , Female , Prognosis , Middle Aged , Aged , Adult , Biomarkers, Tumor/genetics , Genomics/methods , BRCA2 Protein/genetics , Molecular Targeted Therapy , Hepatectomy , Gene Expression Profiling , Tumor Suppressor Protein p53/genetics , DNA-Binding Proteins , Neoplasm Proteins , beta Catenin
3.
Recenti Prog Med ; 115(5): 218-231, 2024 May.
Article in Italian | MEDLINE | ID: mdl-38708533

ABSTRACT

INTRODUCTION: Given the significance of healthcare decisions in women with BRCA1 and BRCA2 mutations and their impact on patients' lives, this study aims to map the existing literature on decision regret in women with BRCA1 and BRCA2 mutations. METHODS: A scoping review was conducted in the following databases: PubMed, Embase, Scopus, CINAHL, Cochrane, and Google Scholar. Inclusion criteria focused on decision regret in the female population with BRCA1 and/or BRCA2 mutations, with no restrictions on the methodologies of the included studies, but only in the English language. The selection process led to the inclusion of 13 studies. RESULTS: The analysis revealed a significant trend toward decision regret among patients facing complex medical choices. The quality of healthcare communication, decision support, and genetic counselling emerged as key factors influencing patients' perceptions and experiences, with direct implications for their quality of life and psychological well-being. The results suggest that these decisions considerably impact patients, both in terms of clinical outcomes and emotional experiences. DISCUSSION: The investigation highlights the vital importance of a personalized care approach, emphasizing the critical role of managing patients' emotional and psychological complexity. Managing decision regret requires acute attention to individual needs and effective communication to mitigate emotional impact and improve patient outcomes. CONCLUSIONS: Insights from a nursing perspective in the analysis of results indicate the need for informed, empathetic, and integrated care that considers the emotional complexity of women with BRCA1 and/or BRCA2 mutations in their lives and health choices.


Subject(s)
BRCA1 Protein , BRCA2 Protein , Breast Neoplasms , Decision Making , Emotions , Mutation , Quality of Life , Humans , Female , BRCA1 Protein/genetics , BRCA2 Protein/genetics , Breast Neoplasms/genetics , Breast Neoplasms/psychology , Genetic Counseling/psychology , Genetic Counseling/methods , Genes, BRCA1 , Communication , Decision Support Techniques , Genes, BRCA2
4.
BMC Med ; 22(1): 199, 2024 May 16.
Article in English | MEDLINE | ID: mdl-38755585

ABSTRACT

BACKGROUND: The prospective phase III multi-centre L-MOCA trial (NCT03534453) has demonstrated the encouraging efficacy and manageable safety profile of olaparib maintenance therapy in the Asian (mainly Chinese) patients with platinum-sensitive relapsed ovarian cancer (PSROC). In this study, we report the preplanned exploratory biomarker analysis of the L-MOCA trial, which investigated the effects of homologous recombination deficiency (HRD) and programmed cell death ligand 1 (PD-L1) expression on olaparib efficacy. METHODS: HRD status was determined using the ACTHRD assay, an enrichment-based targeted next-generation sequencing assay. PD-L1 expression was assessed by SP263 immunohistochemistry assay. PD-L1 expression positivity was defined by the PD-L1 expression on ≥ 1% of immune cells. Kaplan-Meier method was utilised to analyse progression-free survival (PFS). RESULTS: This exploratory biomarker analysis included 225 patients and tested HRD status [N = 190; positive, N = 125 (65.8%)], PD-L1 expression [N = 196; positive, N = 56 (28.6%)], and BRCA1/2 mutation status (N = 219). The HRD-positive patients displayed greater median PFS than the HRD-negative patients [17.9 months (95% CI: 14.5-22.1) versus 9.2 months (95% CI: 7.5-13.8)]. PD-L1 was predominantly expressed on immune cells. Positive PD-L1 expression on immune cells was associated with shortened median PFS in the patients with germline BRCA1/2 mutations [14.5 months (95% CI: 7.4-18.2) versus 22.2 months (95% CI: 18.3-NA)]. Conversely, positive PD-L1 expression on immune cells was associated with prolonged median PFS in the patients with wild-type BRCA1/2 [20.9 months (95% CI: 13.9-NA) versus 8.3 months (95% CI: 6.7-13.8)]. CONCLUSIONS: HRD remained an effective biomarker for enhanced olaparib efficacy in the Asian patients with PSROC. Positive PD-L1 expression was associated with decreased olaparib efficacy in the patients with germline BRCA1/2 mutations but associated with improved olaparib efficacy in the patients with wild-type BRCA1/2. TRIAL REGISTRATION: NCT03534453. Registered at May 23, 2018.


Subject(s)
B7-H1 Antigen , Biomarkers, Tumor , Maintenance Chemotherapy , Ovarian Neoplasms , Phthalazines , Piperazines , Humans , Female , Phthalazines/therapeutic use , Ovarian Neoplasms/drug therapy , Ovarian Neoplasms/genetics , Piperazines/therapeutic use , Biomarkers, Tumor/genetics , Middle Aged , Maintenance Chemotherapy/methods , Aged , Adult , Prospective Studies , Neoplasm Recurrence, Local/drug therapy , BRCA2 Protein/genetics , Antineoplastic Agents/therapeutic use , BRCA1 Protein/genetics , Homologous Recombination
5.
Radiol Clin North Am ; 62(4): 627-642, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38777539

ABSTRACT

Hereditary breast cancers are manifested by pathogenic and likely pathogenic genetic mutations. Penetrance expresses the breast cancer risk associated with these genetic mutations. Although BRCA1/2 are the most widely known genetic mutations associated with breast cancer, numerous additional genes demonstrate high and moderate penetrance for breast cancer. This review describes current genetic testing, details the specific high and moderate penetrance genes for breast cancer and reviews the current approach to screening for breast cancer in patients with these genetic mutations.


Subject(s)
Breast Neoplasms , Genetic Predisposition to Disease , Genetic Testing , Mutation , Humans , Breast Neoplasms/genetics , Breast Neoplasms/diagnostic imaging , Female , Genetic Testing/methods , Genes, BRCA1 , BRCA1 Protein/genetics , Genes, BRCA2 , Penetrance , BRCA2 Protein/genetics
6.
Cells ; 13(10)2024 May 17.
Article in English | MEDLINE | ID: mdl-38786089

ABSTRACT

Resistance to olaparib is the major obstacle in targeted therapy for ovarian cancer (OC) with poly(ADP-ribose) polymerase inhibitors (PARPis), prompting studies on novel combination therapies to enhance olaparib efficacy. Despite identifying various mechanisms, understanding how OC cells acquire PARPi resistance remains incomplete. This study investigated microRNA (miRNA) expression in olaparib-sensitive (PEO1, PEO4) and previously established olaparib-resistant OC cell lines (PEO1-OR) using high-throughput RT-qPCR and bioinformatic analyses. The role of miRNAs was explored regarding acquired resistance and resensitization with the ATR/CHK1 pathway inhibitors. Differentially expressed miRNAs were used to construct miRNA-mRNA regulatory networks and perform functional enrichment analyses for target genes with miRNet 2.0. TCGA-OV dataset was analyzed to explore the prognostic value of selected miRNAs and target genes in clinical samples. We identified potential processes associated with olaparib resistance, including cell proliferation, migration, cell cycle, and growth factor signaling. Resensitized PEO1-OR cells were enriched in growth factor signaling via PDGF, EGFR, FGFR1, VEGFR2, and TGFßR, regulation of the cell cycle via the G2/M checkpoint, and caspase-mediated apoptosis. Antibody microarray analysis confirmed dysregulated growth factor expression. The addition of the ATR/CHK1 pathway inhibitors to olaparib downregulated FGF4, FGF6, NT-4, PLGF, and TGFß1 exclusively in PEO1-OR cells. Survival and differential expression analyses for serous OC patients revealed prognostic miRNAs likely associated with olaparib resistance (miR-99b-5p, miR-424-3p, and miR-505-5p) and resensitization to olaparib (miR-324-5p and miR-424-3p). Essential miRNA-mRNA interactions were reconstructed based on prognostic miRNAs and target genes. In conclusion, our data highlight distinct miRNA profiles in olaparib-sensitive and olaparib-resistant cells, offering molecular insights into overcoming resistance with the ATR/CHK1 inhibitors in OC. Moreover, some miRNAs might serve as potential predictive signature molecules of resistance and therapeutic response.


Subject(s)
Ataxia Telangiectasia Mutated Proteins , BRCA2 Protein , Checkpoint Kinase 1 , Drug Resistance, Neoplasm , Gene Expression Regulation, Neoplastic , Gene Regulatory Networks , MicroRNAs , Ovarian Neoplasms , Phthalazines , Piperazines , RNA, Messenger , Humans , Phthalazines/pharmacology , Phthalazines/therapeutic use , MicroRNAs/genetics , MicroRNAs/metabolism , Female , Piperazines/pharmacology , Piperazines/therapeutic use , Ovarian Neoplasms/genetics , Ovarian Neoplasms/drug therapy , Ovarian Neoplasms/pathology , Checkpoint Kinase 1/metabolism , Checkpoint Kinase 1/genetics , Drug Resistance, Neoplasm/genetics , Drug Resistance, Neoplasm/drug effects , Cell Line, Tumor , Gene Regulatory Networks/drug effects , Ataxia Telangiectasia Mutated Proteins/metabolism , Ataxia Telangiectasia Mutated Proteins/genetics , RNA, Messenger/genetics , RNA, Messenger/metabolism , BRCA2 Protein/genetics , BRCA2 Protein/metabolism , Gene Expression Regulation, Neoplastic/drug effects , Signal Transduction/drug effects
7.
J Transl Med ; 22(1): 484, 2024 May 21.
Article in English | MEDLINE | ID: mdl-38773604

ABSTRACT

BACKGROUND: The aim of this study was to conduct an in silico analysis of a novel compound heterozygous variant in breast cancer susceptibility gene 2 (BRCA2) to clarify its structure-function relationship and elucidate the molecular mechanisms underlying triple-negative breast cancer (TNBC). METHODS: A tumor biopsy sample was obtained from a 42-year-old Chinese woman during surgery, and a maxBRCA™ test was conducted using the patient's whole blood. We obtained an experimentally determined 3D structure (1mje.pdb) of the BRCA2 protein from the Protein Data Bank (PDB) as a relatively reliable reference. Subsequently, the wild-type and mutant structures were predicted using SWISS-MODEL and AlphaFold, and the accuracy of these predictions was assessed through the SAVES online server. Furthermore, we utilized a high ambiguity-driven protein-protein docking (HADDOCK) algorithm and protein-ligand interaction profiler (PLIP) to predict the pathogenicity of the mutations and elucidate pathogenic mechanisms that potentially underlies TNBC. RESULTS: Histological examination revealed that the tumor biopsy sample exhibited classical pathological characteristics of TNBC. Furthermore, the maxBRCA™ test revealed two compound heterozygous BRCA2 gene mutations (c.7670 C > T.pA2557V and c.8356G > A.pA2786T). Through performing in silico structural analyses and constructing of 3D models of the mutants, we established that the mutant amino acids valine and threonine were located in the helical domain and oligonucleotide binding 1 (OB1), regions that interact with DSS1. CONCLUSION: Our analysis revealed that substituting valine and threonine in the helical domain region alters the structure and function of BRCA2 proteins. This mutation potentially affects the binding of proteins and DNA fragments and disrupts interactions between the helical domain region and OB1 with DSS1, potentially leading to the development of TNBC. Our findings suggest that the identified compound heterozygous mutation contributes to the clinical presentation of TNBC, providing new insights into the pathogenesis of TNBC and the influence of compound heterozygous mutations in BRCA2.


Subject(s)
BRCA2 Protein , Computer Simulation , Mutation , Humans , Female , Adult , Mutation/genetics , BRCA2 Protein/genetics , BRCA2 Protein/chemistry , BRCA2 Protein/metabolism , Molecular Docking Simulation , Triple Negative Breast Neoplasms/genetics , Triple Negative Breast Neoplasms/pathology , Genes, BRCA2 , Base Sequence
8.
Pol J Pathol ; 75(1): 1-7, 2024.
Article in English | MEDLINE | ID: mdl-38741424

ABSTRACT

Although BRCA genes are well-known breast cancer genes, the clinicopathological features of breast cancer patients carrying BRCA1/2 pathogenic variants have not been adequately defined. The goals of this study were to determine the distribution of BRCA1/2 variants in the Turkish population and its correlation with clinicopathological features. Clinical data of 151 women who underwent BRCA1/2 gene testing at Mersin University Medical Faculty Hospital between 2016 and 2019 were retrospectively analyzed. BRCA1/2 variants were detected as pathogenic (n = 11), variants of uncertain significance (n = 5), likely benign (n = 3), and benign (n = 81) in breast cancer cases. The BRCA1/2 pathogenic variant carriers had a higher histological grade, rate of triple- negative type, Ki-67 proliferation index, and rate of no special type carcinoma than the group without mutation (p = 0.03, 0.01, 0.04, and 0.02 respectively). We analyzed the distribution of variants we detected in women living in our region and found that pathogenic variants in patients with breast cancer were associated with high histological grade, triple-negative type, high Ki-67 proliferation index, and histological type. Studies in diverse populations are needed to establish a clinicopathological relationship with variants more easily.


Subject(s)
BRCA1 Protein , BRCA2 Protein , Breast Neoplasms , Humans , Female , Middle Aged , BRCA1 Protein/genetics , BRCA2 Protein/genetics , Breast Neoplasms/genetics , Breast Neoplasms/pathology , Adult , Retrospective Studies , Genetic Predisposition to Disease , Aged , Turkey , Mutation , Biomarkers, Tumor/genetics
9.
Int J Gynecol Cancer ; 34(1): 88-98, 2024 Jan 05.
Article in English | MEDLINE | ID: mdl-38805344

ABSTRACT

OBJECTIVE: To evaluate disease characteristics and survival according to BRCA status, administration of poly-(ADP-ribose) polymerase inhibitors (PARPi), and surgery in patients with ovarian cancer and brain metastases. METHODS: This is a monocentric retrospective cohort of patients with ovarian cancer and brain metastases treated between 2000 and 2021. Data were collected by a retrospective review of medical records and analyzed according to: (1) BRCA mutation; (2) PARPi before and after brain metastases; (3) surgery for brain metastases. RESULTS: Eighty-five patients with ovarian cancer and brain metastasis and known BRCA status (31 BRCA mutated (BRCAm), 54 BRCA wild-type (BRCAwt)) were analyzed. Twenty-two patients had received PARPi before brain metastases diagnosis (11 BRCAm, 11 BRCAwt) and 12 after (8 BRCAm, 4 BRCAwt). Brain metastases occurred >1 year later in patients who had received previous PARPi. Survival was longer in the BRCAm group (median post-brain metastasis survival: BRCAm 23 months vs BRCAwt 8 months, p=0.0015). No differences were found based on BRCA status analyzing the population who did not receive PARPi after brain metastasis (median post-brain metastasis survival: BRCAm 8 months vs BRCAwt 8 months, p=0.31). In the BRCAm group, survival was worse in patients who had received previous PARPi (median post-brain metastasis survival: PARPi before, 7 months vs no-PARPi before, 24 months, p=0.003). If PARPi was administered after brain metastases, survival of the overall population improved (median post-brain metastasis survival: PARPi after, 46 months vs no-PARPi after, 8 months, p=0.00038).In cases of surgery for brain metastases, the prognosis seemed better (median post-brain metastasis survival: surgery 13 months vs no-surgery 8 months, p=0.036). Three variables were significantly associated with prolonged survival at multivariate analysis: BRCA mutation, multimodal treatment, and ≤1 previous chemotherapy line. CONCLUSIONS: BRCA mutations might impact brain metastasis occurrence and lead to better outcomes. In a multimodal treatment, surgery seems to affect survival even in cases of extracranial disease. PARPi use should be considered as it seems to prolong survival if administered after brain metastasis.


Subject(s)
Brain Neoplasms , Carcinoma, Ovarian Epithelial , Ovarian Neoplasms , Poly(ADP-ribose) Polymerase Inhibitors , Humans , Female , Brain Neoplasms/secondary , Brain Neoplasms/drug therapy , Brain Neoplasms/surgery , Brain Neoplasms/mortality , Poly(ADP-ribose) Polymerase Inhibitors/administration & dosage , Retrospective Studies , Middle Aged , Ovarian Neoplasms/drug therapy , Ovarian Neoplasms/pathology , Ovarian Neoplasms/mortality , Ovarian Neoplasms/surgery , Ovarian Neoplasms/genetics , Carcinoma, Ovarian Epithelial/drug therapy , Carcinoma, Ovarian Epithelial/surgery , Carcinoma, Ovarian Epithelial/mortality , Carcinoma, Ovarian Epithelial/secondary , Carcinoma, Ovarian Epithelial/pathology , Aged , Adult , BRCA2 Protein/genetics , BRCA1 Protein/genetics
10.
PLoS One ; 19(5): e0299276, 2024.
Article in English | MEDLINE | ID: mdl-38809921

ABSTRACT

BACKGROUND: Familial Pancreatic Cancer (FPC) presents a notable risk, with 3-10% of pancreatic adenocarcinoma cases having a family history. Studies link FPC to syndromes like HBOC, suggesting BRCA1/BRCA2 mutations play a role. BRCA gene functions in DNA repair impact FPC management, influencing sensitivity to therapies like PARP inhibitors. Identifying mutations not only aids FPC treatment but also reveals broader cancer risks. However, challenges persist in selectively applying genetic testing due to cost constraints. This Systematic Review focuses on BRCA1/BRCA2 significance in FPC, diagnostic criteria, prognostic value, and limitations. METHOD: Original articles published from 2013 to January 2023 were sourced from databases such as Scopus, PubMed, ProQuest, and ScienceDirect. Inclusion criteria comprised observational cohort or diagnostic studies related to the role of BRCA1/2 mutation in correlation to familial pancreatic cancer (FPC), while article reviews, narrative reviews, and non-relevant content were excluded. The assessment of bias used ROBINS-I, and the results were organized using PICOS criteria in a Google spreadsheet table. The systematic review adhered to the PRISMA 2020 checklist. RESULT: We analyzed 9 diagnostic studies encompassing 1325 families and 4267 patients from Italy, USA, and Poland. Despite the limitation of limited homogenous PICO studies, our findings effectively present evidence. BRCA1/2 demonstrates benefits in detecting first-degree relatives FPC involvement with 2.26-10 times higher risk. These mutation findings also play an important role since with the BRCA1/2 targeted therapy, Poly-ADP Ribose Polymerase inhibitors (PARP) may give better outcomes of FPC treatment. Analysis of BRCA1 and BRCA2 administration's impact on odds ratio (OR) based on six and five studies respectively. BRCA1 exhibited non-significant effects (OR = 1.26, P = 0.51), while BRCA2 showed significance (OR = 1.68, P = 0.04). No heterogeneity observed, indicating consistent results. Further research on BRCA1 is warranted. CONCLUSION: Detecting the BRCA1/2 mutation gene offers numerous advantages, particularly in its correlation with FPC. For diagnostic and prognostic purposes, testing is strongly recommended for first-degree relatives, who face a significantly higher risk (2.26-10 times) of being affected. Additionally, FPC patients with identified BRCA1/2 mutations exhibit a more favorable prognosis compared to the non-mutated population. This is attributed to the availability of targeted BRCA1/2 therapy, which maximizes treatment outcomes.


Subject(s)
BRCA1 Protein , BRCA2 Protein , Germ-Line Mutation , Pancreatic Neoplasms , Humans , Pancreatic Neoplasms/genetics , BRCA2 Protein/genetics , BRCA1 Protein/genetics , Genetic Predisposition to Disease , Carcinoma
11.
Genes Chromosomes Cancer ; 63(5): e23243, 2024 May.
Article in English | MEDLINE | ID: mdl-38747337

ABSTRACT

Breast cancer susceptibility 1/2 (BRCA1/2) genes play a crucial role in DNA damage repair, yet mutations in these genes increase the susceptibility to tumorigenesis. Exploiting the synthetic lethality mechanism between BRCA1/2 mutations and poly(ADP-ribose) polymerase (PARP) inhibition has led to the development and clinical approval of PARP inhibitor (PARPi), representing a milestone in targeted therapy for BRCA1/2 mutant tumors. This approach has paved the way for leveraging synthetic lethality in tumor treatment strategies. Despite the initial success of PARPis, resistance to these agents diminishes their efficacy in BRCA1/2-mutant tumors. Investigations into PARPi resistance have identified replication fork stability and homologous recombination repair as key factors sensitive to PARPis. Additionally, studies suggest that replication gaps may also confer sensitivity to PARPis. Moreover, emerging evidence indicates a correlation between PARPi resistance and cisplatin resistance, suggesting a potential overlap in the mechanisms underlying resistance to both agents. Given these findings, it is imperative to explore the interplay between replication gaps and PARPi resistance, particularly in the context of platinum resistance. Understanding the impact of replication gaps on PARPi resistance may offer insights into novel therapeutic strategies to overcome resistance mechanisms and enhance the efficacy of targeted therapies in BRCA1/2-mutant tumors.


Subject(s)
BRCA1 Protein , BRCA2 Protein , Drug Resistance, Neoplasm , Mutation , Poly(ADP-ribose) Polymerase Inhibitors , Humans , Poly(ADP-ribose) Polymerase Inhibitors/therapeutic use , Poly(ADP-ribose) Polymerase Inhibitors/pharmacology , Drug Resistance, Neoplasm/genetics , BRCA2 Protein/genetics , BRCA1 Protein/genetics , Female , Breast Neoplasms/genetics , Breast Neoplasms/drug therapy , Antineoplastic Agents/therapeutic use , Antineoplastic Agents/pharmacology , Neoplasms/genetics , Neoplasms/drug therapy
12.
Clin Imaging ; 111: 110189, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38759599

ABSTRACT

OBJECTIVES: Women harboring germline BRCA1/BRCA2 pathogenic sequence variants (PSVs) are at an increased risk for breast cancer. There are no established guidelines for screening during pregnancy and lactation in BRCA carriers. The aim of this study was to evaluate the utility of whole-breast ultrasound (US) screening in pregnant and lactating BRCA PSV carriers. METHODS: Data were retrospectively collected from medical records of BRCA PSV carriers between 2014 and 2020, with follow-up until 2021. Associations between imaging intervals, number of examinations performed and pregnancy-associated breast cancers (PABCs) were examined. PABCs and cancers diagnosed at follow-up were evaluated and characteristics were compared between the two groups. RESULTS: Overall 212 BRCA PSV carriers were included. Mean age was 33.6 years (SD 3.93, range 25-43 years). During 274 screening periods at pregnancy and lactation, eight (2.9 %) PABCs were diagnosed. An additional eight cancers were diagnosed at follow-up. Three out of eight (37.5 %) PABCs were diagnosed by US, whereas clinical breast examination (n = 3), mammography (n = 1) and MRI (n = 1) accounted for the other PACB diagnoses. One PABC was missed by US. The interval from negative imaging to cancer diagnosis was significantly shorter for PABCs compared with cancers diagnosed at follow-up (3.96 ± 2.14 vs. 11.2 ± 4.46 months, P = 0.002). CONCLUSION: In conclusion, pregnant BRCA PSV carriers should not delay screening despite challenges like altered breast tissue and hesitancy towards mammography. If no alternatives exist, whole-breast ultrasound can be used. For lactating and postpartum women, a regular screening routine alternating between mammography and MRI is recommended.


Subject(s)
BRCA1 Protein , Breast Neoplasms , Early Detection of Cancer , Lactation , Ultrasonography, Mammary , Humans , Female , Pregnancy , Breast Neoplasms/genetics , Breast Neoplasms/diagnostic imaging , Adult , Retrospective Studies , Early Detection of Cancer/methods , Ultrasonography, Mammary/methods , BRCA1 Protein/genetics , BRCA2 Protein/genetics , Pregnancy Complications, Neoplastic/genetics , Pregnancy Complications, Neoplastic/diagnostic imaging , Mammography/methods , Heterozygote
13.
Nat Commun ; 15(1): 4430, 2024 May 24.
Article in English | MEDLINE | ID: mdl-38789420

ABSTRACT

Histone H2AX plays a key role in DNA damage signalling in the surrounding regions of DNA double-strand breaks (DSBs). In response to DNA damage, H2AX becomes phosphorylated on serine residue 139 (known as γH2AX), resulting in the recruitment of the DNA repair effectors 53BP1 and BRCA1. Here, by studying resistance to poly(ADP-ribose) polymerase (PARP) inhibitors in BRCA1/2-deficient mammary tumours, we identify a function for γH2AX in orchestrating drug-induced replication fork degradation. Mechanistically, γH2AX-driven replication fork degradation is elicited by suppressing CtIP-mediated fork protection. As a result, H2AX loss restores replication fork stability and increases chemoresistance in BRCA1/2-deficient tumour cells without restoring homology-directed DNA repair, as highlighted by the lack of DNA damage-induced RAD51 foci. Furthermore, in the attempt to discover acquired genetic vulnerabilities, we find that ATM but not ATR inhibition overcomes PARP inhibitor (PARPi) resistance in H2AX-deficient tumours by interfering with CtIP-mediated fork protection. In summary, our results demonstrate a role for H2AX in replication fork biology in BRCA-deficient tumours and establish a function of H2AX separable from its classical role in DNA damage signalling and DSB repair.


Subject(s)
BRCA1 Protein , BRCA2 Protein , DNA Replication , Drug Resistance, Neoplasm , Histones , Poly(ADP-ribose) Polymerase Inhibitors , Humans , BRCA1 Protein/metabolism , BRCA1 Protein/deficiency , BRCA1 Protein/genetics , Histones/metabolism , Poly(ADP-ribose) Polymerase Inhibitors/pharmacology , DNA Replication/drug effects , BRCA2 Protein/metabolism , BRCA2 Protein/genetics , BRCA2 Protein/deficiency , Cell Line, Tumor , Female , Drug Resistance, Neoplasm/genetics , Animals , Ataxia Telangiectasia Mutated Proteins/metabolism , Ataxia Telangiectasia Mutated Proteins/genetics , DNA Breaks, Double-Stranded , Breast Neoplasms/genetics , Breast Neoplasms/metabolism , Breast Neoplasms/pathology , Breast Neoplasms/drug therapy , Mice , Tumor Suppressor p53-Binding Protein 1/metabolism , Tumor Suppressor p53-Binding Protein 1/genetics , DNA Repair , Carrier Proteins/metabolism , Carrier Proteins/genetics , DNA Damage , Rad51 Recombinase/metabolism , Rad51 Recombinase/genetics
14.
JCO Clin Cancer Inform ; 8: e2300251, 2024 May.
Article in English | MEDLINE | ID: mdl-38709234

ABSTRACT

PURPOSE: The emergence of large real-world clinical databases and tools to mine electronic medical records has allowed for an unprecedented look at large data sets with clinical and epidemiologic correlates. In clinical cancer genetics, real-world databases allow for the investigation of prevalence and effectiveness of prevention strategies and targeted treatments and for the identification of barriers to better outcomes. However, real-world data sets have inherent biases and problems (eg, selection bias, incomplete data, measurement error) that may hamper adequate analysis and affect statistical power. METHODS: Here, we leverage a real-world clinical data set from a large health network for patients with breast cancer tested for variants in BRCA1 and BRCA2 (N = 12,423). We conducted data cleaning and harmonization, cross-referenced with publicly available databases, performed variant reassessment and functional assays, and used functional data to inform a variant's clinical significance applying American College of Medical Geneticists and the Association of Molecular Pathology guidelines. RESULTS: In the cohort, White and Black patients were over-represented, whereas non-White Hispanic and Asian patients were under-represented. Incorrect or missing variant designations were the most significant contributor to data loss. While manual curation corrected many incorrect designations, a sizable fraction of patient carriers remained with incorrect or missing variant designations. Despite the large number of patients with clinical significance not reported, original reported clinical significance assessments were accurate. Reassessment of variants in which clinical significance was not reported led to a marked improvement in data quality. CONCLUSION: We identify the most common issues with BRCA1 and BRCA2 testing data entry and suggest approaches to minimize data loss and keep interpretation of clinical significance of variants up to date.


Subject(s)
BRCA1 Protein , BRCA2 Protein , Breast Neoplasms , Germ-Line Mutation , Registries , Humans , Breast Neoplasms/genetics , Breast Neoplasms/epidemiology , Female , BRCA1 Protein/genetics , BRCA2 Protein/genetics , Middle Aged , Genetic Predisposition to Disease , Adult , Electronic Health Records , Aged
15.
Int J Mol Sci ; 25(9)2024 Apr 24.
Article in English | MEDLINE | ID: mdl-38731844

ABSTRACT

More than 20% of metastatic prostate cancer carries genomic defects involving DNA damage repair pathways, mainly in homologous recombination repair-related genes. The recent approval of olaparib has paved the way to precision medicine for the treatment of metastatic prostate cancer with PARP inhibitors in this subset of patients, especially in the case of BRCA1 or BRCA2 pathogenic/likely pathogenic variants. In face of this new therapeutic opportunity, many issues remain unsolved. This narrative review aims to describe the relationship between homologous recombination repair deficiency and prostate cancer, the techniques used to determine homologous recombination repair status in prostate cancer, the crosstalk between homologous recombination repair and the androgen receptor pathway, the current evidence on PARP inhibitors activity in metastatic prostate cancer also in homologous recombination repair-proficient tumors, as well as emerging mechanisms of resistance to PARP inhibitors. The possibility of combination therapies including a PARP inhibitor is an attractive option, and more robust data are awaited from ongoing phase II and phase III trials outlined in this manuscript.


Subject(s)
Poly(ADP-ribose) Polymerase Inhibitors , Prostatic Neoplasms , Recombinational DNA Repair , Humans , Male , Prostatic Neoplasms/genetics , Prostatic Neoplasms/drug therapy , Prostatic Neoplasms/pathology , Poly(ADP-ribose) Polymerase Inhibitors/therapeutic use , BRCA2 Protein/genetics , BRCA2 Protein/deficiency , Neoplasm Metastasis , BRCA1 Protein/genetics , BRCA1 Protein/deficiency , Phthalazines/therapeutic use , Phthalazines/pharmacology , Receptors, Androgen/genetics , Receptors, Androgen/metabolism , Piperazines
16.
JCO Glob Oncol ; 10: e2300417, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38635940

ABSTRACT

PURPOSE: Genetic cancer risk assessment (GCRA) provides pathogenic variant (PV) carriers with the invaluable opportunity to undertake timely cancer risk-reducing (RR) measures and initiate cascade testing (CT). This study describes the uptake of these strategies and the related barriers among breast cancer-associated germline PV carriers in Mexico. METHODS: Carriers who were at least 6 months after disclosure of genetic test results at two GCRA referral centers were invited to answer a survey assessing sociodemographic characteristics, awareness of their carrier status and its implications, uptake of RR measures according to international guidelines by PV, CT initiation, and associated challenges. RESULTS: Of the eligible carriers, 246/384 (64%) answered the survey (median age: 44 years). Most were female (88%), married/in domestic partnership (66%), and had personal breast/ovarian cancer history (61%). PVs included BRCA1/2 (75%), CHEK2 (10%), PALB2 (5%), ATM (5%), NF1 (2%), RAD51C (2%), PTEN (1%), and TP53 (1%). Most (87%) participants were aware of their carrier status. When recommended, 37% underwent RR bilateral mastectomy, 48% RR oophorectomy, 70% annual mammogram, and 20% breast magnetic resonance imaging. Challenges hindering the uptake of RR measures included financial limitations (67%), lack of recommendation by their physician (35%), and fear (24%). Nearly all (98%) claimed sharing their results with their relatives. CT was initiated in 63% of families and was associated with carriers being married/in domestic partnership (P = .04) and believing GCRA was useful (P < .001). CONCLUSION: Despite the resource-constrained setting, relevant rates of RR measures and CT were observed. Targeted interventions to reduce out-of-pocket expenses and improve patient-physician communication and patients' understanding on carrier status are warranted to enhance the overall benefit of GCRA and ultimately improve the provision of patient-centered care to both carriers and their at-risk relatives.


Subject(s)
Breast Neoplasms , Humans , Female , Adult , Male , Breast Neoplasms/genetics , Breast Neoplasms/surgery , BRCA1 Protein/genetics , Mexico/epidemiology , Genetic Predisposition to Disease , BRCA2 Protein/genetics , Mastectomy , Germ Cells
17.
BMC Cancer ; 24(1): 499, 2024 Apr 19.
Article in English | MEDLINE | ID: mdl-38641594

ABSTRACT

BACKGROUND: Germline mutations in BRCA1 and BRCA2 genes are among the main causes of hereditary ovarian cancer. Identifying these mutations may reduce cancer risk, facilitate early detection, and enable personalized treatment. However, genetic testing is limited in the Brazilian Public Health System, and data regarding germline mutations in many regions are scarce. Therefore, the study aimed to investigate the prevalence of germline mutations in BRCA1 and BRCA2 in women with ovarian cancer treated in the Public Health System in Pernambuco, Brazil. METHODS: A cross-sectional study was conducted in the Hereditary Cancer Program from two reference oncological centers in Pernambuco. Women (n = 45) with high-grade serous ovarian cancer underwent genetic counseling and DNA sequencing for BRCA1 and BRCA2 genes. RESULTS: The prevalence of deleterious mutations in the BRCA1 and BRCA2 genes was 33%. Of the 15 germline mutations found, 13 were in BRCA1 and 2 in BRCA2; two mutations of unknown clinical significance were also found in BRCA2. Mutations c.5266dupC and c.2215 A > T were the most frequent; each was mutation observed in three patients. Additionally, the mutations c.7645dupT and c.921dupT were reported for the first time. CONCLUSION: One in three women showed a pathogenic mutation, demonstrating a significant prevalence of germline mutations in this sample. Additionally, the small sample revealed an interesting number of mutations, indicating the need to explore more regions of the country.


Subject(s)
Genes, BRCA2 , Ovarian Neoplasms , Humans , Female , Brazil/epidemiology , Germ-Line Mutation , Cross-Sectional Studies , Public Health , Genetic Predisposition to Disease , Ovarian Neoplasms/epidemiology , Ovarian Neoplasms/genetics , Ovarian Neoplasms/pathology , BRCA2 Protein/genetics , BRCA1 Protein/genetics
19.
PLoS One ; 19(4): e0301271, 2024.
Article in English | MEDLINE | ID: mdl-38573891

ABSTRACT

OBJECTIVE: To assess the cost-effectiveness and budget impact of olaparib as a maintenance therapy in platinum-responsive, metastatic pancreatic cancer patients harboring a germline BRCA1/2 mutation, using the Swiss context as a model. METHODS: Based on data from the POLO trial, published literature and local cost data, we developed a partitioned survival model of olaparib maintenance including full costs for BRCA1/2 germline testing compared to FOLFIRI maintenance chemotherapy and watch-and-wait. We calculated the incremental cost-effectiveness ratio (ICER) for the base case and several scenario analyses and estimated 5-year budget impact. RESULTS: Comparing olaparib with watch-and wait and maintenance chemotherapy resulted in incremental cost-effectiveness ratios of CHF 2,711,716 and CHF 2,217,083 per QALY gained, respectively. The 5-year costs for the olaparib strategy in Switzerland would be CHF 22.4 million, of which CHF 11.4 million would be accounted for by germline BRCA1/2 screening of the potentially eligible population. This would amount to a budget impact of CHF 15.4 million (USD 16.9 million) versus watch-and-wait. CONCLUSIONS: Olaparib is not a cost-effective maintenance treatment option. Companion diagnostics are an equally important cost driver as the drug itself.


Subject(s)
Ovarian Neoplasms , Pancreatic Neoplasms , Piperazines , Female , Humans , BRCA1 Protein/genetics , Ovarian Neoplasms/genetics , Platinum/therapeutic use , BRCA2 Protein/genetics , Phthalazines/therapeutic use , Pancreatic Neoplasms/drug therapy , Pancreatic Neoplasms/genetics , Pancreatic Neoplasms/pathology , Germ Cells/pathology , Cost-Benefit Analysis
20.
JAMA Netw Open ; 7(4): e247421, 2024 Apr 01.
Article in English | MEDLINE | ID: mdl-38639936

ABSTRACT

Importance: In young-onset breast cancer (YOBC), a diagnosis within 5 to 10 years of childbirth is associated with increased mortality. Women with germline BRCA1/2 pathogenic variants (PVs) are more likely to be diagnosed with BC at younger ages, but the impact of childbirth on mortality is unknown. Objective: To determine whether time between most recent childbirth and BC diagnosis is associated with mortality among patients with YOBC and germline BRCA1/2 PVs. Design, Setting, and Participants: This prospective cohort study included women with germline BRCA1/2 PVs diagnosed with stage I to III BC at age 45 years or younger between 1950 and 2021 in the United Kingdom, who were followed up until November 2021. Data were analyzed from December 3, 2021, to November 29, 2023. Exposure: Time between most recent childbirth and subsequent BC diagnosis, with recent childbirth defined as 0 to less than 10 years, further delineated to 0 to less than 5 years and 5 to less than 10 years. Main Outcomes and Measures: The primary outcome was all-cause mortality, censored at 20 years after YOBC diagnosis. Mortality of nulliparous women was compared with the recent post partum groups and the 10 or more years post partum group. Cox proportional hazards regression analyses were adjusted for age, tumor stage, and further stratified by tumor estrogen receptor (ER) and BRCA gene status. Results: Among 903 women with BRCA PVs (mean [SD] age at diagnosis, 34.7 [6.1] years; mean [SD] follow-up, 10.8 [9.8] years), 419 received a BC diagnosis 0 to less than 10 years after childbirth, including 228 women diagnosed less than 5 years after childbirth and 191 women diagnosed 5 to less than 10 years after childbirth. Increased all-cause mortality was observed in women diagnosed within 5 to less than 10 years post partum (hazard ratio [HR], 1.56 [95% CI, 1.05-2.30]) compared with nulliparous women and women diagnosed 10 or more years after childbirth, suggesting a transient duration of postpartum risk. Risk of mortality was greater for women with ER-positive BC in the less than 5 years post partum group (HR, 2.35 [95% CI, 1.02-5.42]) and ER-negative BC in the 5 to less than 10 years post partum group (HR, 3.12 [95% CI, 1.22-7.97]) compared with the nulliparous group. Delineated by BRCA1 or BRCA2, mortality in the 5 to less than 10 years post partum group was significantly increased, but only for BRCA1 carriers (HR, 2.03 [95% CI, 1.15-3.58]). Conclusions and Relevance: These findings suggest that YOBC with germline BRCA PVs was associated with increased risk for all-cause mortality if diagnosed within 10 years after last childbirth, with risk highest for ER-positive BC diagnosed less than 5 years post partum, and for ER-negative BC diagnosed 5 to less than 10 years post partum. BRCA1 carriers were at highest risk for poor prognosis when diagnosed at 5 to less than 10 years post partum. No such associations were observed for BRCA2 carriers. These results should inform genetic counseling, prevention, and treatment strategies for BRCA PV carriers.


Subject(s)
Breast Neoplasms , Female , Humans , BRCA1 Protein/genetics , BRCA2 Protein/genetics , Breast Neoplasms/pathology , Genetic Predisposition to Disease , Germ Cells/pathology , Postpartum Period , Prospective Studies , Adult
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