RESUMO
Importance: Between 5% and 10% of breast cancer cases are associated with an inherited germline pathogenic or likely pathogenic variant (GPV) in a breast cancer susceptibility gene (BCSG), which could alter local and systemic therapy recommendations. Traditional genetic testing criteria misses a proportion of these cases. Objective: To evaluate the prevalence and clinicopathological associations of GPVs in 2 groups of BCSGs among an ethnically diverse cohort of women with newly diagnosed breast cancer. Design, Setting, and Participants: This cross-sectional study, conducted at 3 Montreal hospitals between September 2019 and April 2022, offered universal genetic counseling and testing to all women with a first diagnosis of invasive breast cancer. Women were offered an obligatory primary panel of BRCA1, BRCA2, and PALB2 (B1B2P2) and an optional secondary panel of 14 additional BCSGs. Eligible participants were women 18 years of age or older who received a diagnosis of a first primary invasive breast cancer not more than 6 months before the time of referral to the study. Data were analyzed from November 2023 to June 2024. Results: Of 1017 referred patients, 805 were eligible and offered genetic counseling and testing, and 729 of those 805 (90.6%) consented to be tested. The median age at breast cancer diagnosis was 53 years (range, 23-91 years), and 65.4% were White and of European ancestry. Fifty-four GPVs were identified in 53 patients (7.3%), including 39 patients (5.3%) with B1B2P2 and 15 patients (2.1%) with 6 of the 14 secondary panel BCSGs (ATM, BARD1, BRIP1, CHEK2, RAD51D, and STK11). On multivariable analysis, clinical factors independently associated with B1B2P2-positive status included being younger than 40 years of age at diagnosis (odds ratio [OR], 6.83; 95% CI, 2.22-20.90), triple-negative breast cancer (OR, 3.19; 95% CI, 1.20-8.43), high grade disease (OR, 1.68; 95% CI, 1.05-2.70), and family history of ovarian cancer (OR, 9.75; 95% CI, 2.65-35.85). Of 39 B1B2P2-positive patients, 13 (33.3%) were eligible for poly(adenosine diphosphate-ribose) polymerase (PARP) inhibitors. Conclusions and Relevance: In this cross-sectional universal genetic testing study of women with newly diagnosed invasive breast cancer, the prevalence of GPVs was 7.3%, with 5.3% of patients testing positive for B1B2P2. Among B1B2P2-women women, one-third were eligible for PARP inhibitors.
Assuntos
Neoplasias da Mama , Predisposição Genética para Doença , Testes Genéticos , Humanos , Feminino , Pessoa de Meia-Idade , Neoplasias da Mama/genética , Neoplasias da Mama/diagnóstico , Testes Genéticos/métodos , Testes Genéticos/estatística & dados numéricos , Estudos Transversais , Adulto , Idoso , Proteína do Grupo de Complementação N da Anemia de Fanconi/genética , Aconselhamento Genético/estatística & dados numéricos , Proteína BRCA1/genética , Proteína BRCA2/genéticaRESUMO
The Guidelines for Clinical Practice for carriers of pathogenic variants in clinically relevant cancer predisposition genes define the steps of primary and secondary prevention that should be provided to these individuals at high risk of developing hereditary cancer in the Czech Republic. The drafting of the guidelines was organized by the Oncogenetics Working Group of the Society for Medical Genetics and Genomics of J. E. Purkyne Czech Medical Society (SLG CLS JEP) in cooperation with the representatives of oncology and oncogynecology. The guidelines are based on the current recommendations of the National Comprehensive Cancer Network (NCCN), European Society of Medical Oncology (ESMO) and take into account the capacity of the Czech healthcare system.
Assuntos
Proteínas Mutadas de Ataxia Telangiectasia , Proteína BRCA2 , Quinase do Ponto de Checagem 2 , Proteína do Grupo de Complementação N da Anemia de Fanconi , Predisposição Genética para Doença , Mutação em Linhagem Germinativa , Humanos , Quinase do Ponto de Checagem 2/genética , Proteína do Grupo de Complementação N da Anemia de Fanconi/genética , Feminino , Proteínas Mutadas de Ataxia Telangiectasia/genética , Proteína BRCA2/genética , Masculino , Proteína BRCA1/genética , República Tcheca , Neoplasias Ovarianas/genética , Neoplasias da Próstata/genética , Neoplasias Pancreáticas/genética , Neoplasias da Mama/genéticaRESUMO
BRCA1/2 proteins function in genome stability by promoting repair of double-stranded DNA breaks through homologous recombination and by protecting stalled replication forks from nucleolytic degradation. In BRCA1/2-deficient cancer cells, extensively degraded replication forks can be rescued through distinct fork recovery mechanisms that also promote cell survival. Here, we identified a novel pathway mediated by the E3 ubiquitin ligase RAD18, the E2-conjugating enzyme UBC13, the recombination factor PALB2, the E3 ubiquitin ligase RNF168 and PCNA ubiquitination that promotes fork recovery in BRCA1- but not BRCA2-deficient cells. We show that this pathway does not promote fork recovery by preventing replication fork reversal and degradation in BRCA1-deficient cells. We propose a mechanism whereby the RAD18-UBC13-PALB2-RNF168 axis facilitates resumption of DNA synthesis by promoting re-annealing of the complementary single-stranded template strands of the extensively degraded forks, thereby allowing re-establishment of a functional replication fork. We also provide preliminary evidence for the potential clinical relevance of this novel fork recovery pathway in BRCA1-mutated cancers, as RAD18 is over-expressed in BRCA1-deficient cancers, and RAD18 loss compromises cell viability in BRCA1-deficient cancer cells.
Assuntos
Proteína BRCA1 , Replicação do DNA , Proteínas de Ligação a DNA , Proteína do Grupo de Complementação N da Anemia de Fanconi , Enzimas de Conjugação de Ubiquitina , Ubiquitina-Proteína Ligases , Humanos , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina-Proteína Ligases/genética , Proteína BRCA1/metabolismo , Proteína BRCA1/genética , Proteína BRCA1/deficiência , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/genética , Enzimas de Conjugação de Ubiquitina/metabolismo , Enzimas de Conjugação de Ubiquitina/genética , Linhagem Celular Tumoral , Proteína do Grupo de Complementação N da Anemia de Fanconi/genética , Proteína do Grupo de Complementação N da Anemia de Fanconi/metabolismo , Ubiquitinação , Antígeno Nuclear de Célula em Proliferação/metabolismo , Antígeno Nuclear de Célula em Proliferação/genética , Reparo do DNARESUMO
PURPOSE: Limited data are available regarding the partner and localizer of BRCA2 (PALB2) in Chinese patients with early breast cancer. This study aimed to assess the spectrum and characteristics of germline PALB2 pathogenic variants in this population. METHODS: Peripheral blood samples were collected from 1556 patients diagnosed with BRCA1/2-negative early-onset breast cancer. All coding regions and exonâintron boundaries of the PALB2 genes were screened through next-generation sequencing. RESULTS: The prevalence of PALB2 pathogenic variants was approximately 0.77% in the cohort. Eleven PALB2 pathogenic variants were identified in twelve participants, including five frameshift mutations and six nonsense mutations. All other variants were detected once, except for PALB2 c.1056_1057del (detected twice). Two PALB2 carriers (2/12, 16.7%) have documented family history of breast cancer and/or ovarian cancer. Patients with a positive family history exhibited a threefold higher possibility of being identified as PALB2 carriers than those without a family history (2% vs. 0.69%), although the difference was not statistically significant (p = 0.178). Compared to non-carriers, PALB2 carriers has a tendency to appear in younger age (≤ 30 years) (25% vs 14.4%), human epidermal growth factor receptor-2 (HER2)-negative status (83.3% vs. 70.2%), and diagnosed with invasive micropapillary carcinoma (16.7% vs 3.1%). CONCLUSION: The prevalence of the germline PALB2 pathogenic variants was approximately 0.77% in Chinese patients with BRCA1/2-negative early-onset breast cancer. Our findings is crucial for understanding population-specific genetic risks and offering insights that can enhance genetic counseling and genetic testing strategies in this population.
Assuntos
Idade de Início , Neoplasias da Mama , Proteína do Grupo de Complementação N da Anemia de Fanconi , Mutação em Linhagem Germinativa , Humanos , Feminino , Proteína do Grupo de Complementação N da Anemia de Fanconi/genética , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Neoplasias da Mama/epidemiologia , Adulto , Pessoa de Meia-Idade , China/epidemiologia , Predisposição Genética para Doença , Adulto Jovem , Proteína BRCA2/genéticaRESUMO
Some patients with metastatic prostate cancer carry a pathogenic germline variant (PV) in a gene, that is mainly associated with an increased risk of breast cancer in women. If they test positive for such a PV, prostate cancer patients are encouraged to disclose the genetic test result to relatives who are at risk in case the carrier status changes the relatives' medical care. Our study aimed to investigate how men who learned they carry a PV in BRCA1, BRCA2, PALB2, CHEK2 or ATM disclosed their carrier status to at-risk relatives and to assess the possible psychological burden for the carrier and their perception of the burden for relatives. In total, 23 men with metastatic prostate cancer carrying a PV completed the IRI questionnaire about family communication; 14 also participated in a semi-structured interview. Patients felt highly confident in discussing the genetic test result with relatives. The diagnosis of prostate cancer was experienced as a burden, whereas being informed about genetic testing results did in most cases not add to this burden. Two patients encountered negative experiences with family communication, as they considered the genetic test result to be more urgent than their relatives. This mixed-methods study shows that metastatic prostate cancer patients with a PV in genes mainly associated with increased risk of breast cancer feel well-equipped to communicate about this predisposition in their families. Carriers felt motivated to disclose their genetic test result to relatives. Most of them indicated that the disclosure was not experienced as a psychological burden.
Assuntos
Predisposição Genética para Doença , Testes Genéticos , Mutação em Linhagem Germinativa , Neoplasias da Próstata , Humanos , Masculino , Neoplasias da Próstata/genética , Neoplasias da Próstata/psicologia , Neoplasias da Próstata/patologia , Pessoa de Meia-Idade , Idoso , Predisposição Genética para Doença/psicologia , Proteína BRCA2/genética , Revelação , Proteína do Grupo de Complementação N da Anemia de Fanconi/genética , Proteína BRCA1/genética , Quinase do Ponto de Checagem 2/genética , Neoplasias da Mama/genética , Neoplasias da Mama/psicologia , Neoplasias da Mama/patologia , Família/psicologia , Feminino , Proteínas Mutadas de Ataxia Telangiectasia/genética , AdultoRESUMO
Multi-gene panel testing allows many cancer susceptibility genes to be tested quickly at a lower cost making such testing accessible to a broader population. Thus, more patients carrying pathogenic germline mutations in various cancer-susceptibility genes are being identified. This creates a great opportunity, as well as an urgent need, to counsel these patients about appropriate risk-reducing management strategies. Counseling hinges on accurate estimates of age-specific risks of developing various cancers associated with mutations in a specific gene, ie, penetrance estimation. We propose a meta-analysis approach based on a Bayesian hierarchical random-effects model to obtain penetrance estimates by integrating studies reporting different types of risk measures (eg, penetrance, relative risk, odds ratio) while accounting for the associated uncertainties. After estimating posterior distributions of the parameters via a Markov chain Monte Carlo algorithm, we estimate penetrance and credible intervals. We investigate the proposed method and compare with an existing approach via simulations based on studies reporting risks for two moderate-risk breast cancer susceptibility genes, ATM and PALB2. Our proposed method is far superior in terms of coverage probability of credible intervals and mean square error of estimates. Finally, we apply our method to estimate the penetrance of breast cancer among carriers of pathogenic mutations in the ATM gene.
Assuntos
Teorema de Bayes , Predisposição Genética para Doença , Penetrância , Humanos , Predisposição Genética para Doença/genética , Proteínas Mutadas de Ataxia Telangiectasia/genética , Neoplasias da Mama/genética , Feminino , Proteína do Grupo de Complementação N da Anemia de Fanconi/genética , Simulação por Computador , Cadeias de Markov , Neoplasias/genética , Neoplasias/epidemiologia , Proteínas Supressoras de Tumor/genética , Medição de Risco/métodos , Medição de Risco/estatística & dados numéricos , Método de Monte Carlo , Metanálise como Assunto , Mutação em Linhagem Germinativa , Modelos EstatísticosRESUMO
Breast cancer risk have been discussed to be associated with polymorphisms in genes as well as abnormal DNA damage repair function. This study aims to assess the relationship between genes single nucleotide polymorphisms (SNPs) related to DNA damage repair and female breast cancer risk in Chinese population. A case-control study containing 400 patients and 400 healthy controls was conducted. Genotype was identified using the sequence MassARRAY method and expression of estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor-2 (HER-2) in tumor tissues was analyzed by immunohistochemistry assay. The results revealed that ATR rs13091637 decreased breast cancer risk influenced by ER, PR (CT/TT vs. CC: adjusted odds ratio [OR] = 1.54, 95% confidence interval [CI]: 1.04-2.27, p = 0.032; CT/TT vs. CC: adjusted OR = 1.63, 95%CI: 1.14-2.35, p = 0.008) expression. Stratified analysis revealed that PALB2 rs16940342 increased breast cancer risk in response to menstrual status (AG/GG vs. AA: adjusted OR = 1.72, 95%CI: 1.13-2.62, p = 0.011) and age of menarche (AG/GG vs. AA: adjusted OR = 1.54, 95%CI: 1.03-2.31, p = 0.037), whereas ATM rs611646 and Ku70 rs132793 were associated with reduced breast cancer risk influenced by menarche (GA/AA vs. GG: adjusted OR = 0.50, 95%CI: 0.30-0.95, p = 0.033). In a summary, PALB2 rs16940342, ATR rs13091637, ATM rs611646, and Ku70 rs132793 were associated with breast cancer risk.
Assuntos
Proteínas Mutadas de Ataxia Telangiectasia , Neoplasias da Mama , Reparo do DNA , Predisposição Genética para Doença , Autoantígeno Ku , Polimorfismo de Nucleotídeo Único , Receptores de Progesterona , Humanos , Feminino , Neoplasias da Mama/genética , Reparo do DNA/genética , Pessoa de Meia-Idade , Proteínas Mutadas de Ataxia Telangiectasia/genética , Estudos de Casos e Controles , Adulto , Autoantígeno Ku/genética , Receptores de Progesterona/genética , Receptores de Progesterona/metabolismo , Receptor ErbB-2/genética , Dano ao DNA/genética , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo , Proteína do Grupo de Complementação N da Anemia de Fanconi/genética , Fatores de RiscoRESUMO
Deleterious germline mutations in multiple genes confer an increased breast cancer (BC) risk. Immunohistochemical (IHC) expression of protein products of mutated high-risk genes has not been investigated in BC. We hypothesized that pathogenic mutations may lead to an abnormal IHC expression pattern in the tumor cells. BCs with deleterious germline mutations in CHEK2, ATM, PALB2 & PTEN were identified. Immunohistochemistry was performed using Dako staining platform on formalin fixed paraffin embedded tumor tissue. Primary antibodies for PALB2 (ab202970), ATM [2C1(1A10)}, CHK2 (EPR4325), and PTEN (138G6) proteins were used for BCs with respective deleterious mutations. IHC expression was assessed in tumor and adjacent benign breast tissue. Total 27 BCs with 10 CHEK2, 9 ATM, 6 PALB2 & 2 PTEN deleterious germline mutations were identified. IHC staining was performed on 8 CHEK2, 7 ATM, 6 PALB2 & 2 PTEN cases. Abnormal CHEK2 IHC staining was identified in 7/8(88%) BCs. Three distinct CHK2 IHC patterns were noted: 1) Strong diffuse nuclear positivity (5 BC), 2) Null-pattern (2 BC), & 3) Normal breast-like staining in 1 BC Four of 5 (80%) strong CHK2 staining BC had missense CHEK2 mutations. Null-pattern was present with a missense & a frameshift mutation. Normal breast-like CHEK2 IHC staining pattern was present in 1 BC with CHEK2 frameshift mutation. Loss of nuclear/cytoplasmic PTEN IHC expression was noted in 2 in-situ carcinomas. Abnormal PTEN and CHK2 IHC were present in atypical ductal hyperplasia and flat epithelial atypia. ATM and PALB2 IHC expression patterns were similar in tumor cells and benign breast epithelium: mild to moderate intensity nuclear and cytoplasmic staining. We report abnormal CHEK2 IHC expression in 88% of BCs with pathogenic CHEK2 mutations. With PTEN and CHEK2 pathogenic mutations, abnormal IHC patterns are seen in early atypical proliferative lesions. IHC may be applied to identify CHEK2 & PTEN mutated BCs and precursor lesions.
Assuntos
Proteínas Mutadas de Ataxia Telangiectasia , Biomarcadores Tumorais , Neoplasias da Mama , Quinase do Ponto de Checagem 2 , Proteína do Grupo de Complementação N da Anemia de Fanconi , Mutação em Linhagem Germinativa , Imuno-Histoquímica , PTEN Fosfo-Hidrolase , Proteínas Supressoras de Tumor , Humanos , Feminino , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , PTEN Fosfo-Hidrolase/genética , Quinase do Ponto de Checagem 2/genética , Proteínas Mutadas de Ataxia Telangiectasia/genética , Pessoa de Meia-Idade , Proteína do Grupo de Complementação N da Anemia de Fanconi/genética , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/análise , Adulto , Proteínas Supressoras de Tumor/genética , Idoso , Predisposição Genética para Doença , Proteínas Nucleares/genéticaRESUMO
INTRODUCTION: The impact of timing of genetic testing on uptake of risk reducing mastectomy (RRM) in affected female BRCA1/2 or PALB2 carriers remains an area of evolving interest, particularly with the introduction of mainstream genetic testing initiatives. METHODS: Women with stage I-III breast cancer and a confirmed germline pathogenic variant in BRCA1/2 or PALB2 between 2000 and 2023 were identified from an institutional genetics database. Uptake of RRM was evaluated according to disclosure of genetic testing results before or after index surgery for a first diagnosis of breast cancer. RESULTS: The cohort included 287 female BRCA1/2 or PALB2 carriers with a median age of 44 years (IQR, 36-52). Overall, 155 (54 %) carriers received genetic testing results before and 132 (46 %) after index breast surgery. Receipt of genetic testing results before surgery was associated with a higher rate of index bilateral mastectomy (58.7 % vs. 7.6 %, p < 0.001) and a commensurate decrease in adjuvant radiation (41.9 % vs. 74.2 %, p < 0.001). At a median follow up of 4.4 years after genetic testing, 219 (76.3 %) affected carriers had undergone bilateral RRM, including 83.9 % with preoperative knowledge and 67.4 % of patients with postoperative knowledge of their germline pathogenic variant (log rank, p < 0.001). On multivariate regression, disclosure of genetic testing results before index breast surgery was independently associated with long-term uptake of bilateral mastectomy (HR 1.69, 95 % CI 1.21-2.38). CONCLUSION: Genetic testing results delivered prior to index breast surgery increase uptake of bilateral RRM in affected BRCA1/2 and PALB2 carriers. Efforts to mainstream genetic testing would help optimize surgical decision-making.
Assuntos
Neoplasias da Mama , Proteína do Grupo de Complementação N da Anemia de Fanconi , Testes Genéticos , Mastectomia Profilática , Humanos , Feminino , Neoplasias da Mama/genética , Neoplasias da Mama/cirurgia , Neoplasias da Mama/radioterapia , Proteína do Grupo de Complementação N da Anemia de Fanconi/genética , Adulto , Pessoa de Meia-Idade , Mutação em Linhagem Germinativa , Revelação , Mastectomia , Fatores de Tempo , Heterozigoto , Genes BRCA2 , Proteína BRCA1/genética , Predisposição Genética para Doença , Genes BRCA1 , Proteína BRCA2/genética , Procedimentos DesnecessáriosRESUMO
Heterozygous mutations in any of three major genes, BRCA1, BRCA2 and PALB2, are associated with high-risk hereditary breast cancer susceptibility frequently seen as familial disease clustering. PALB2 is a key interaction partner and regulator of several vital cellular activities of BRCA1 and BRCA2, and is thus required for DNA damage repair and alleviation of replicative and oxidative stress. Little is however known about how PALB2-deficiency affects cell function beyond that, especially in the three-dimensional setting, and also about its role during early steps of malignancy development. To answer these questions, we have generated biologically relevant MCF10A mammary epithelial cell lines with mutations that are comparable to certain clinically important PALB2 defects. We show in a non-cancerous background how both mono- and biallelically PALB2-mutated cells exhibit gross spontaneous DNA damage and mitotic aberrations. Furthermore, PALB2-deficiency disturbs three-dimensional spheroid morphology, increases the migrational capacity and invasiveness of the cells, and broadly alters their transcriptome profiles. TGFß signaling and KRT14 expression are enhanced in PALB2-mutated cells and their inhibition and knock down, respectively, lead to partial restoration of cell functions. KRT14-positive cells are also more abundant with DNA damage than KRT14-negative cells. The obtained results indicate comprehensive cellular changes upon PALB2 mutations, even in the presence of half dosage of wild type PALB2 and demonstrate how PALB2 mutations may predispose their carriers to malignancy.
Assuntos
Neoplasias , Transdução de Sinais , Humanos , Reparo do DNA , Células Epiteliais , Mama , Proteína do Grupo de Complementação N da Anemia de Fanconi/genéticaRESUMO
BACKGROUND: An estimated 20% to 30% of men with advanced prostate cancer carry a mutation in DNA damage repair genes, of which half are estimated to be germline. Eligibility criteria for germline genetic testing expanded significantly for Ontario patients in May 2021 and many centers adopted a "mainstream" model, defined as oncologist-initiated genetic testing. METHODS: We conducted a retrospective chart review to report on the first-year mainstream experience of a large tertiary oncologic center, the Sunnybrook Odette Cancer Centre. All patients who underwent mainstream at the discretion of their treating physician were included. A subset underwent somatic profiling as part of clinical trial screening. Descriptive statistics were used to report baseline clinicopathologic characteristics and treatments received. RESULTS: Between May 1, 2021, and May 30, 2022, 174 patients with prostate cancer underwent mainstream germline genetic testing with a 19-gene panel. Median age was 75 (IQR 68-80), and 82% of patients were diagnosed with either de novo metastatic or high-risk localized prostate adenocarcinoma. Fourteen patients (8%; 95% CI 4%-12%) were found to have a deleterious germline mutation, including pathogenic or likely pathogenic variants in BRCA1/2, ATM, CHEK2, PMS2, RAD51C, HOXB13, and BRIP1. Forty-nine patients (28%; 95% CI 21%-35%) were found to have a variant of uncertain significance. Thirty-four patients also had next-generation sequencing (NGS) of their somatic tissue. Among this subset, 8 of 34 (23%) had an alteration in homologous recombination repair (HRR) genes. Of the 14 patients with a germline mutation, none had a prior personal history of malignancy and 6 (43%) did not have any first- or second-degree relatives with history of prostate, pancreatic, breast, or ovarian cancer. CONCLUSION: We report on the real-world characteristics of prostate cancer patients who underwent mainstream germline genetic testing. Personal history and family history of cancer cannot reliably stratify patients for the presence of pathogenic germline variants.
Assuntos
Testes Genéticos , Mutação em Linhagem Germinativa , Neoplasias da Próstata , Centros de Atenção Terciária , Humanos , Masculino , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Idoso , Testes Genéticos/métodos , Estudos Retrospectivos , Idoso de 80 Anos ou mais , Ontário , Proteína BRCA1/genética , Proteína BRCA2/genética , Predisposição Genética para Doença , Quinase do Ponto de Checagem 2/genética , Endonuclease PMS2 de Reparo de Erro de Pareamento/genética , Proteínas de Ligação a DNA/genética , Proteína do Grupo de Complementação N da Anemia de Fanconi/genética , Proteínas Mutadas de Ataxia Telangiectasia/genética , Proteínas de Homeodomínio , RNA Helicases , Proteínas de Grupos de Complementação da Anemia de FanconiRESUMO
BACKGROUND: DNA repair mechanisms are essential for tumorigenesis and disruption of HR mechanism is an important predisposing factor of human breast cancers (BC). PALB2 is an important part of the HR. There are similarities between canine mammary tumours (CMT) and BCs. As its human counterpart, PALB2 mutations could be a predisposing factor of CMT. OBJECTIVES: In this study, we aimed to investigate the impacts of PALB2 variants on tumorigenesis and canine mammary tumor (CMT) malignancy. METHODS: We performed Sanger sequencing to detect germline mutations in the WD40 domain of the canine PALB2 gene in CMT patients. We conducted in silico analysis to investigate the variants, and compared the germline PALB2 mutations in humans that cause breast cancer (BC) with the variants detected in dogs with CMT. RESULTS: We identified an intronic (c.3096+8C>G) variant, two exonic (p.A1050V and p.R1354R) variants, and a 3' UTR variant (c.4071T>C). Of these, p.R1354R and c.4071T>C novel variants were identified for the first time in this study. We found that the p.A1050V mutation had a significant effect. However, we could not determine sufficient similarity due to the differences in nucleotide/amino acid sequences between two species. Nonetheless, possible variants of human sequences in the exact location as their dog counterparts are associated with several cancer types, implying that the variants could be crucial for tumorigenesis in dogs. Our results did not show any effect of the variants on tumor malignancy. CONCLUSIONS: The current project is the first study investigating the relationship between the PALB2 gene WD40 domain and CMTs. Our findings will contribute to a better understanding of the pathogenic mechanism of the PALB2 gene in CMTs. In humans, variant positions in canines have been linked to cancer-related phenotypes such as familial BC, endometrial tumor, and hereditary cancer predisposition syndrome. The results of bioinformatics analyses should be investigated through functional tests or case-control studies.
Assuntos
Doenças do Cão , Proteína do Grupo de Complementação N da Anemia de Fanconi , Neoplasias Mamárias Animais , Animais , Cães , Feminino , Humanos , Neoplasias da Mama/genética , Neoplasias da Mama/veterinária , Neoplasias da Mama/patologia , Carcinogênese , Doenças do Cão/genética , Doenças do Cão/patologia , Proteína do Grupo de Complementação N da Anemia de Fanconi/química , Proteína do Grupo de Complementação N da Anemia de Fanconi/genética , Predisposição Genética para Doença , Neoplasias Mamárias Animais/genética , Neoplasias Mamárias Animais/patologia , Mutação , Proteínas Supressoras de Tumor/genéticaRESUMO
PURPOSE: We performed a pooled analysis of multiple trials of poly(ADP-ribose) polymerase inhibitors (PARPi) in metastatic castration-resistant prostate cancer (mCRPC) to investigate the efficacy of PARPi in each individual homologous recombination repair (HRR) mutated (m) gene. PATIENTS AND METHODS: We pooled patient-level data from trials of PARPi in mCRPC that reported mutation status in individual HRR genes. Any HRR gene with available data across all the randomized trials of PARPi in first-line mCRPC was selected. The hazard ratios (HRs; 95% CI) for radiographic progression-free survival (rPFS; by blinded independent review) and overall survival (OS) of a PARPi plus an androgen receptor pathway inhibitor (ARPI) relative to placebo plus an ARPI in the pool of three randomized trials in first-line mCRPC were calculated using Kaplan-Meier estimates and a Cox proportional hazards model. RESULTS: In ATMm (N = 268), rPFS HR was 1.05 (0.74 to 1.49) and OS HR was 1.18 (0.82 to 1.71). In BRCA1m (N = 64), rPFS HR was 0.51 (0.23 to 1.1) and OS HR was 0.74 (0.34 to 1.61). In BRCA2m (N = 422), rPFS HR was 0.31 (0.23 to 0.42) and OS HR was 0.66 (0.49 to 0.89). In CDK12m (N = 164), rPFS HR was 0.50 (0.32 to 0.80) and OS HR was 0.63 (0.39 to 0.99). In CHEK2m (N = 172), rPFS HR was 1.06 (0.67 to 1.66) and OS HR was 1.53 (0.95 to 2.46). In PALB2m (N = 41) rPFS HR was 0.52 (0.23 to 1.17) and OS HR was 0.78 (0.34 to 1.8). CONCLUSION: In this pooled analysis, benefit from PARPi appeared greatest for patients with BRCA1m, BRCA2m, CDK12m, and PALB2m. Given limitations of this exploratory analysis, the apparent lack of benefit from PARPi in patients with CHEK2m or ATMm should be further explored in future clinical trials.
Assuntos
Proteína BRCA2 , Mutação , Inibidores de Poli(ADP-Ribose) Polimerases , Neoplasias de Próstata Resistentes à Castração , Ensaios Clínicos Controlados Aleatórios como Assunto , Reparo de DNA por Recombinação , Humanos , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/genética , Neoplasias de Próstata Resistentes à Castração/patologia , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Masculino , Reparo de DNA por Recombinação/genética , Proteína BRCA2/genética , Proteína BRCA1/genética , Estados Unidos , Quinase do Ponto de Checagem 2/genética , Quinases Ciclina-Dependentes/genética , Quinases Ciclina-Dependentes/antagonistas & inibidores , Proteínas Mutadas de Ataxia Telangiectasia/genética , Proteína do Grupo de Complementação N da Anemia de Fanconi/genética , Intervalo Livre de Progressão , Antagonistas de Receptores de Andrógenos/uso terapêutico , Idoso , Receptores Androgênicos/genética , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêuticoRESUMO
Male breast cancer (MBC) accounts for approximately 1% of all breast cancers and among these infiltrating lobular carcinomas (ILC) represents only 1-2% of all MBC cases. Pleomorphic invasive lobular carcinoma (PILC) is an aggressive variant of ILC with only eight cases reported until now in males. Up to 10% of MBC cases have a germline pathogenic variant in a predisposing gene such as BRCA1 and BRCA2 genes. Mutations in PALB2 (partner and localizer of BRCA2) have been reported in men with breast cancer, with a frequency that ranges from 0.8 to 6.4%, but it has never been reported in male ILC. Here, we report a rare and interesting case of an invasive pleomorphic/solid lobular carcinoma, which carries a pathogenic variant in PALB2 gene, and a family history of breast cancer without other well defined risk factors for developing this type of neoplasia. In addition, we review the current literature.
Assuntos
Neoplasias da Mama Masculina , Neoplasias da Mama , Carcinoma Lobular , Masculino , Humanos , Carcinoma Lobular/genética , Carcinoma Lobular/patologia , Mutação em Linhagem Germinativa , Neoplasias da Mama/genética , Neoplasias da Mama Masculina/genética , Neoplasias da Mama Masculina/patologia , Mutação , Predisposição Genética para Doença , Proteína do Grupo de Complementação N da Anemia de Fanconi/genéticaRESUMO
OPINION STATEMENT: An important subgroup of pancreatic ductal adenocarcinomas (PDACs) harbor pathogenic variants in BRCA1, BRCA2, or PALB2. These tumors are exquisitely sensitive to platinum-based chemotherapy and patients may experience deep and durable responses to this treatment. PARP inhibitors offer potential respite from the cumulative toxicities of chemotherapy as they significantly extend progression-free survival compared to a chemotherapy holiday. Given the lack of proven survival benefit, the decision to use a maintenance PARP inhibitor rather than continue chemotherapy should be individualized. Interestingly, in both published clinical trials of maintenance PARP inhibitors, there is a striking range of interpatient benefit: Even in the platinum-sensitive setting, roughly 25% of tumors appear to be PARP inhibitor refractory (progressive disease within 2 months of starting treatment), 50% sustain moderate benefit (up to 2 years), and 25% are hyper-responsive (more than 2 years of benefit). This finding highlights the need to refine our understanding of which patients will respond to maintenance PARP inhibitors, both by being able to identify biallelic loss and by deepening our knowledge of resistance mechanisms and who develops them. Recent data supports that reversion mutations are common in PARP inhibitor refractory patients, but we have little understanding of the mechanisms that drive delayed resistance and long-term responses. Identifying which patients are more prone to certain mechanisms of resistance and tackling them with specific treatment strategies are areas of active investigation. Additionally, given that PARP inhibitors have limited overall efficacy for most patients, upfront combination strategies are an important future strategy.
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Antineoplásicos , Neoplasias Ovarianas , Neoplasias Pancreáticas , Humanos , Feminino , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Antineoplásicos/uso terapêutico , Mutação , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Proteína BRCA2/genética , Proteína BRCA1/genética , Poli(ADP-Ribose) Polimerases/genética , Neoplasias Ovarianas/tratamento farmacológico , Proteína do Grupo de Complementação N da Anemia de Fanconi/genéticaRESUMO
Female BRCA1/2 and PALB2 germline pathogenic variant carriers have an increased lifetime risk of breast cancer and may wish to consider risk-reducing mastectomy (RRM) for surgical prevention. Quantifying the residual lifetime risk and absolute benefit from RRM requires careful consideration of a patient's age, pathogenic variant, and their personal history of breast or ovarian cancer. Historically, patients have been counselled that RRM does not necessarily prolong survival relative to high-risk surveillance, although recent studies suggest a possible survival benefit of RRM in BRCA1 carriers. The uptake of RRM has increased dramatically over the last several decades yet varies according to sociodemographic factors and geographic region. The increased adoption of nipple-sparing mastectomy techniques, ability to avoid axillary staging, and availability of reconstructive options for most germline pathogenic variant carriers has helped to minimize the morbidity of RRM. Preoperative discussions should include evidence regarding postmastectomy sensation, the potential for supplemental surgery, pregnancy-related chest wall changes, and the need for continued clinical surveillance. Approaches that include sensation preservation and robotic nipple-sparing mastectomy are an area of evolving research that may be more widely adopted in the future.
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Neoplasias da Mama , Mastectomia , Gravidez , Humanos , Feminino , Neoplasias da Mama/genética , Neoplasias da Mama/cirurgia , Proteína BRCA1/genética , Proteína BRCA2/genética , Aconselhamento , Células Germinativas , Proteína do Grupo de Complementação N da Anemia de Fanconi/genéticaRESUMO
BACKGROUND: Mountain areas of the North Caucasus host several large ethnic communities that have preserved their national identity over the centuries. METHODS: This study involved high-grade serous ovarian cancer (HGSOC) and breast cancer (BC) patients from Dagestan (HGSOC: 37; BC: 198), Kabardino-Balkaria (HGSOC: 68; BC: 155), North Ossetia (HGSOC: 51; BC: 104), Chechnya (HGSOC: 68; BC: 79), Ingushetia (HGSOC: 19; BC: 103), Karachay-Cherkessia (HGSOC: 13; BC: 47), and several Armenian settlements (HGSOC: 16; BC: 101). The group of BC patients was enriched by young-onset and/or family history-positive and/or bilateral and/or receptor triple-negative cases. The entire coding region of BRCA1, BRCA2, PALB2, and ATM genes was analyzed by next-generation sequencing. RESULTS: A significant contribution of BRCA1/2 pathogenic variants (PVs) to HGSOC and BC development was observed across all North Caucasus regions (HGSOC: 19-39%; BC: 6-13%). Founder alleles were identified in all ethnic groups studied, e.g., BRCA1 c.3629_3630delAG in Chechens, BRCA2 c.6341delC in North Ossetians, BRCA2 c.5351dupA in Ingush, and BRCA1 c.2907_2910delTAAA in Karachays. Some BRCA1/2 alleles, particularly BRCA2 c.9895C > T, were shared by several nationalities. ATM PVs were detected in 14 patients, with c.1673delG and c.8876_8879delACTG alleles occurring twice each. PALB2 heterozygosity was observed in 5 subjects, with one variant seen in 2 unrelated women. CONCLUSION: This study adds to the evidence for the global-wide contribution of BRCA1/2 genes to HGSOC and BC morbidity, although the spectrum of their PVs is a subject of ethnicity-specific variations. The data on founder BRCA1/2 alleles may be considered when adjusting the BRCA1/2 testing procedure to the ethnic origin of patients.
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Proteínas Mutadas de Ataxia Telangiectasia , Neoplasias da Mama , População do Leste Europeu , Neoplasias Ovarianas , Humanos , Feminino , Proteína BRCA1/genética , Proteína BRCA2/genética , Etnicidade , Alelos , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Predisposição Genética para Doença , Neoplasias Ovarianas/genética , Proteína do Grupo de Complementação N da Anemia de Fanconi/genéticaRESUMO
BACKGROUND AND AIMS: Cancer predisposition goes beyond BRCA and DNA Mismatch Repair (MMR) genes since multi-gene panel testing has become the routine diagnostic tool for hereditary cancer suspicion (HCS) cases. CHEK2 and PALB2 are some of the foremost-mutated non-BRCA/MMR actionable genes in families with a significant familial aggregation. Therefore, the purpose of this work is to unravel which tumours other than breast, ovary or colorectal display the patients. MATERIALS AND METHODS: We have analysed 528 probands that meet the inclusion criteria for Hereditary Breast and Ovarian Cancer and Lynch Syndrome established by our Hereditary Cancer Regional Program with a customized 35 genes-panel by using Ion Torrent™ Technology. RESULTS: We have identified pathogenic variants (PVs) in 61 families (1.55%), of which more than half (31 probands) harboured PVs in CHEK2 and PALB2 genes. Ours results reveal that not only were PVs CHEK2 and PALB2 carriers more likely to have family history of cancer not limited to breast, ovarian or colorectal cancers, but also they are prone to other extracolonic cancers, noteworthy endometrial and gastric cancers. CONCLUSIONS: Multigene panel testing improves the chance of finding PVs in actionable genes in families with HCS. In addition, the coexistence of variants should be recorded to implement a polygenic risk algorithm that might explain the missing heritability in the aforementioned families.
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Neoplasias da Mama , Neoplasias Colorretais , Neoplasias Ovarianas , Feminino , Humanos , Mutação em Linhagem Germinativa/genética , Predisposição Genética para Doença , Neoplasias Ovarianas/genética , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/genética , Neoplasias da Mama/genética , Testes Genéticos/métodos , Quinase do Ponto de Checagem 2/genética , Proteína do Grupo de Complementação N da Anemia de Fanconi/genéticaRESUMO
OBJECTIVE: The purpose of this study was to recontact individuals with clinically actionable test results identified through a retrospective research study and to provide a framework for laboratories to recontact patients. METHODS: Genetic testing was conducted on 2977 individuals originally referred for BRCA1 and BRCA2 hereditary breast and ovarian cancer testing that had a negative genetic test result. A gene panel was used to identify pathogenic variants in known or newly discovered genes that could explain the underlying cause of disease; however, analysis was restricted to PALB2 for the purposes of this study. A patient recontact decision tree was developed to assist in the returning of updated genetic test results to clinics and patients. RESULTS: Novel clinically actionable pathogenic variants were identified in the PALB2 gene in 18 participants (0.6%), the majority of whom were recontacted with their new or updated genetic test results. Eight individuals were unable to be recontacted; five individuals had already learnt about their new or updated findings from genetic testing outside the context of this study; three individuals prompted cascade testing in family members; two individuals were deceased. CONCLUSION: Novel pathogenic variants in PALB2 were identified in 18 individuals through retrospective gene panel testing. Recontacting these individuals regarding these new or updated findings had a range of outcomes. The process of conveying genomic results within this framework can be effectively accomplished while upholding patient autonomy, potentially leading to advantageous outcomes for patients and their families.
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Dever de Recontatar , Proteína do Grupo de Complementação N da Anemia de Fanconi , Laboratórios Clínicos , Feminino , Humanos , Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias da Mama/genética , Proteína do Grupo de Complementação N da Anemia de Fanconi/genética , Predisposição Genética para Doença , Testes Genéticos , Estudos RetrospectivosRESUMO
BACKGROUND: The homologous recombination (HR) repair pathway for DNA damage, particularly the BRCA1 and BRCA2 genes, has become a target for cancer therapy, with poly ADP-ribose polymerase (PARP) inhibitors showing significant outcomes in treating germline BRCA1/2 (gBRCA1/2) mutated breast cancer. Recent studies suggest that some patients with somatic BRCA1/2 (sBRCA1/2) mutation or mutations in HR-related genes other than BRCA1/2 may benefit from PARP inhibitors as well, particularly those with PALB2 mutations. The current analysis aims to evaluate the prevalence of genetic alterations specific to BRCA1, BRCA2, and PALB2 in a large cohort of Taiwanese breast cancer patients through tumor-targeted sequencing. METHODS: A total of 924 consecutive assays from 879 Taiwanese breast cancer patients underwent tumor-targeted sequencing (Thermo Fisher Oncomine Comprehensive Assay v3). We evaluated BRCA1, BRCA2, and PALB2 mutational profiles, with variants annotated and curated by the ClinVAR, the Oncomine™ Knowledgebase Reporter, and the OncoKB™. We also conducted reflex germline testing using either whole exome sequencing (WES) or whole genome sequencing (WGS), which is ongoing. RESULTS: Among the 879 patients analyzed (924 assays), 130 had positive mutations in BRCA1 (3.1%), BRCA2 (8.6%), and PALB2 (5.2%), with a total of 14.8% having genetic alterations. Co-occurrence was noted between BRCA1/BRCA2, BRCA1/PALB2, and BRCA2/PALB2 mutations. In BRCA1-mutated samples, only p.K654fs was observed in three patients, while other variants were observed no more than twice. For BRCA2, p.N372H was the most common (26 patients), followed by p.S2186fs, p.V2466A, and p.X159_splice (5 times each). For PALB2, p.I887fs was the most common mutation (30 patients). This study identified 176 amino acid changes; 60.2% (106) were not documented in either ClinVAR or the Oncomine™ Knowledgebase Reporter. Using the OncoKB™ for annotation, 171 (97.2%) were found to have clinical implications. For the result of reflex germline testing, three variants (BRCA1 c.1969_1970del, BRCA1 c.3629_3630del, BRCA2 c.8755-1G > C) were annotated as Pathogenic/Likely pathogenic (P/LP) variants by ClinVar and as likely loss-of-function or likely oncogenic by OncoKB; while one variant (PALB2 c.448C > T) was not found in ClinVar but was annotated as likely loss-of-function or likely oncogenic by OncoKB. CONCLUSION: Our study depicted the mutational patterns of BRCA1, BRCA2, and PALB2 in Taiwanese breast cancer patients through tumor-only sequencing. This highlights the growing importance of BRCA1/2 and PALB2 alterations in breast cancer susceptibility risk and the treatment of index patients. We also emphasized the need to meticulously annotate variants in cancer-driver genes as well as actionable mutations across multiple databases.