BRCA2

Gene Summary

Gene:BRCA2; BRCA2 DNA repair associated
Aliases: FAD, FACD, FAD1, GLM3, BRCC2, FANCD, PNCA2, FANCD1, XRCC11, BROVCA2
Location:13q13.1
Summary:Inherited mutations in BRCA1 and this gene, BRCA2, confer increased lifetime risk of developing breast or ovarian cancer. Both BRCA1 and BRCA2 are involved in maintenance of genome stability, specifically the homologous recombination pathway for double-strand DNA repair. The BRCA2 protein contains several copies of a 70 aa motif called the BRC motif, and these motifs mediate binding to the RAD51 recombinase which functions in DNA repair. BRCA2 is considered a tumor suppressor gene, as tumors with BRCA2 mutations generally exhibit loss of heterozygosity (LOH) of the wild-type allele. [provided by RefSeq, Dec 2008]
Databases:OMIM, HGNC, Ensembl, GeneCard, Gene
Protein:breast cancer type 2 susceptibility protein
Source:NCBIAccessed: 31 August, 2019

Ontology:

What does this gene/protein do?
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Pathways:What pathways are this gene/protein implicaed in?
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Cancer Overview

A tumor suppressor gene located on human chromosome 13 at locus 13q12.3. Mutations in this gene predispose humans to breast and ovarian cancer. It encodes a large, nuclear protein that is an essential component of DNA repair pathways, suppressing the formation of gross chromosomal rearrangements. (from Genes Dev 2000;14(11):1400-6) [Source: MeSH, 2014]

Research Indicators

Publications Per Year (1994-2019)
Graph generated 31 August 2019 using data from PubMed using criteria.

Literature Analysis

Mouse over the terms for more detail; many indicate links which you can click for dedicated pages about the topic.

Tag cloud generated 31 August, 2019 using data from PubMed, MeSH and CancerIndex

Specific Cancers (15)

Data table showing topics related to specific cancers and associated disorders. Scope includes mutations and abnormal protein expression.

Note: list is not exhaustive. Number of papers are based on searches of PubMed (click on topic title for arbitrary criteria used).

Fanconi Anemia - Complementation Group D1

Latest Publications

Stasenko M, Cybulska P, Feit N, et al.
Brain metastasis in epithelial ovarian cancer by BRCA1/2 mutation status.
Gynecol Oncol. 2019; 154(1):144-149 [PubMed] Article available free on PMC after 01/07/2020 Related Publications
OBJECTIVE: To evaluate clinical outcomes of patients with BRCA-associated ovarian cancer who developed brain metastases (BM).
METHODS: Patients with epithelial ovarian, fallopian tube, and primary peritoneal cancer (EOC) and BM, treated at a single institution from 1/1/2008-7/1/2018, were identified from two institutional databases. Charts and medical records were retrospectively reviewed for clinical characteristics and germline BRCA mutation status. Appropriate statistics were used.
RESULTS: Of 3649 patients with EOC, 91 had BM (2.5%). Germline mutation status was available for 63 (69%) cases; 21 (35%) of these harbored a BRCA1/2 mutation (15 BRCA1, 6 BRCA2). Clinical characteristics were similar between groups. BM were diagnosed at a median of 31 months (95% CI, 22.6-39.4) in BRCA-mutated (mBRCA) and 32 months (95% CI, 23.7-40.3) in wild-type BRCA (wtBRCA) (p = 0.78) patients. Brain metastases were the only evidence of disease at time of BM diagnoses in 48% (n = 10) mBRCA and 19% (n = 8) wtBRCA (p = 0.02) patients. There was no difference in treatment of BM by mutation status (p = 0.84). Survival from time of BM diagnosis was 29 months (95%CI, 15.5-42.5) in mBRCA and 9 months (95% CI, 5.5-12.5) in wtBRCA patients, with an adjusted hazard ratio (HR) of 0.53, p = 0.09; 95% CI, 0.25-1.11. HR was adjusted for presence of systemic disease at time of BM diagnosis.
CONCLUSION: This is the largest study to date comparing outcomes in patients with EOC and BM by mutation status. mBRCA patients were more likely to have isolated BM, which may be a factor in their long survival. This supports the pursuit of aggressive treatment for mBRCA EOC patients with BM. Additional studies examining the correlation of BRCA mutational status with BM are warranted.

Tomao F, Musacchio L, Di Mauro F, et al.
Is BRCA mutational status a predictor of platinum-based chemotherapy related hematologic toxicity in high-grade serous ovarian cancer patients?
Gynecol Oncol. 2019; 154(1):138-143 [PubMed] Related Publications
OBJECTIVE: To evaluate hematologic adverse effect profiles associated with frontline platinum-based chemotherapy in ovarian cancer patients according to BRCA 1/2 mutational status.
METHODS: Patients with high-grade serous ovarian cancer and a known BRCA mutational status who received in frontline 6 cycles of Carboplatin (AUC 5) plus Paclitaxel 175 mg/mq were retrospectively selected from our databases. Hematologic toxicity profiles of BRCA mutated patients were compared to non-mutated patients, according to EORTC Common Terminology Criteria for Adverse Events (CTCAE_4.02).
RESULTS: Totally, 176 women of whom 58 (33%) were BRCA1/2 mutation carriers - 40 BRCA1 (69%) and 18 (31%) BRCA2 mutations carriers - and 118 (67%) non-carriers were identified. A significant higher frequency of thrombocytopenia (24% vs 5%; p < 0.001), anemia (21% vs 7%; p = 0.006) and neutropenia (62% vs 27%; p ≤0.001) was observed in BRCA mutated patients, resulting in a higher percentage of granulocyte-colony stimulating growth factors injection (12% versus 1%, p < 0.001) and dose delay (19% versus 27%, p = 0.005). The multivariate analysis confirmed that granulocyte-colony stimulating growth factors injection and dose delay were statistically significantly more frequent in BRCA mutated patients (OR 2.567, 95% CI 1.136-5.798, p = 0.035; OR 3.860, 95% CI 1.098-13.570, p = 0.023). Finally, the total number of hematologic adverse events compared between the two groups of patients during the entire treatment period showed a substantial higher rate of hematologic adverse events in BRCA mutated population.
CONCLUSIONS: Germline BRCA 1/2 mutations are associated with a higher hematologic toxicity in patients with ovarian cancer who underwent platinum-based chemotherapy.

Sui Y, Wu T, Li F, et al.
YY1/BCCIP Coordinately Regulates P53-Responsive Element (p53RE)-Mediated Transactivation of p21
Int J Mol Sci. 2019; 20(9) [PubMed] Article available free on PMC after 01/07/2020 Related Publications
Transactivation of

Zakrzewski F, Gieldon L, Rump A, et al.
Targeted capture-based NGS is superior to multiplex PCR-based NGS for hereditary BRCA1 and BRCA2 gene analysis in FFPE tumor samples.
BMC Cancer. 2019; 19(1):396 [PubMed] Article available free on PMC after 01/07/2020 Related Publications
BACKGROUND: With the introduction of Olaparib treatment for BRCA-deficient recurrent ovarian cancer, testing for somatic and/or germline mutations in BRCA1/2 genes in tumor tissues became essential for treatment decisions. In most cases only formalin-fixed paraffin-embedded (FFPE) samples, containing fragmented and chemically modified DNA of minor quality, are available. Thus, multiplex PCR-based sequencing is most commonly applied in routine molecular testing, which is predominantly focused on the identification of known hot spot mutations in oncogenes.
METHODS: We compared the overall performance of an adjusted targeted capture-based enrichment protocol and a multiplex PCR-based approach for calling of pathogenic SNVs and InDels using DNA extracted from 13 FFPE tissue samples. We further applied both strategies to seven blood samples and five matched FFPE tumor tissues of patients with known germline exon-spanning deletions and gene-wide duplications in BRCA1/2 to evaluate CNV detection based solely on panel NGS data. Finally, we analyzed DNA from FFPE tissues of 11 index patients from families suspected of having hereditary breast and ovarian cancer, of whom no blood samples were available for testing, in order to identify underlying pathogenic germline BRCA1/2 mutations.
RESULTS: The multiplex PCR-based protocol produced inhomogeneous coverage among targets of each sample and between samples as well as sporadic amplicon drop out, leading to insufficiently or non-covered nucleotides, which subsequently hindered variant detection. This protocol further led to detection of PCR-artifacts that could easily have been misinterpreted as pathogenic mutations. No such limitations were observed by application of an adjusted targeted capture-based protocol, which allowed for CNV calling with 86% sensitivity and 100% specificity. All pathogenic CNVs were confirmed in the five matched FFPE tumor samples from patients carrying known pathogenic germline mutations and we additionally identified somatic loss of the second allele in BRCA1/2. Furthermore we detected pathogenic BRCA1/2 variants in four the eleven FFPE samples from patients of whom no blood was available for analysis.
CONCLUSIONS: We demonstrate that an adjusted targeted capture-based enrichment protocol is superior to commonly applied multiplex PCR-based protocols for reliable BRCA1/2 variant detection, including CNV-detection, using FFPE tumor samples.

Chen X, Chen F, Ren Y, et al.
IL-6 signaling contributes to radioresistance of prostate cancer through key DNA repair-associated molecules ATM, ATR, and BRCA 1/2.
J Cancer Res Clin Oncol. 2019; 145(6):1471-1484 [PubMed] Related Publications
PURPOSE: To study an association between IL-6 signaling and resistance to radiotherapy of prostate cancer (PCa) and explore the molecular mechanisms involved.
METHODS: IL-6 expressing C4-2 and CWR22Rv1 (C4-2IL-6/CWRIL-6) and vector control (C4-2vec/CWRvec) cell lines were developed. Radiation-sensitivities of these cells were compared in clonogenic assay, Comet assay, and γH2AX staining. In xenograft animal studies, radiation-sensitivity of C4-2IL-6 cell-derived tumors vs. C4-2vec cell-derived tumors was investigated. To reveal IL-6 downstream molecules involved in DNA repair after radiation, qPCR and Western blot analyses as well as immunofluorescence staining were performed. Transcriptional control of IL-6 on ATM and ATR molecules was also investigated.
RESULTS: We found C4-2IL-6 and CWRIL-6 cells survived better than their vector control cells after irradiation, and animal studies confirmed such in vitro results. We discovered that DNA repair-related molecules such as ATM, ATR, BRCA1, and BRCA2 were significantly upregulated in irradiated IL-6 expressing cells compared with vector control cells. We further defined that IL-6 signaling regulated cellular expressions of ATM and ATR at the transcriptional level through the activation of Stat3 signaling pathway.
CONCLUSIONS: IL-6 leads to PCa resistance to radiation through upregulation of DNA repair associated molecules ATM, ATR, BRCA1, and BRCA2.

Gröschel S, Hübschmann D, Raimondi F, et al.
Defective homologous recombination DNA repair as therapeutic target in advanced chordoma.
Nat Commun. 2019; 10(1):1635 [PubMed] Article available free on PMC after 01/07/2020 Related Publications
Chordomas are rare bone tumors with few therapeutic options. Here we show, using whole-exome and genome sequencing within a precision oncology program, that advanced chordomas (n = 11) may be characterized by genomic patterns indicative of defective homologous recombination (HR) DNA repair and alterations affecting HR-related genes, including, for example, deletions and pathogenic germline variants of BRCA2, NBN, and CHEK2. A mutational signature associated with HR deficiency was significantly enriched in 72.7% of samples and co-occurred with genomic instability. The poly(ADP-ribose) polymerase (PARP) inhibitor olaparib, which is preferentially toxic to HR-incompetent cells, led to prolonged clinical benefit in a patient with refractory chordoma, and whole-genome analysis at progression revealed a PARP1 p.T910A mutation predicted to disrupt the autoinhibitory PARP1 helical domain. These findings uncover a therapeutic opportunity in chordoma that warrants further exploration, and provide insight into the mechanisms underlying PARP inhibitor resistance.

Shahi RB, De Brakeleer S, Caljon B, et al.
Identification of candidate cancer predisposing variants by performing whole-exome sequencing on index patients from BRCA1 and BRCA2-negative breast cancer families.
BMC Cancer. 2019; 19(1):313 [PubMed] Article available free on PMC after 01/07/2020 Related Publications
BACKGROUND: In the majority of familial breast cancer (BC) families, the etiology of the disease remains unresolved. To identify missing BC heritability resulting from relatively rare variants (minor allele frequency ≤ 1%), we have performed whole exome sequencing followed by variant analysis in a virtual panel of 492 cancer-associated genes on BC patients from BRCA1 and BRCA2 negative families with elevated BC risk.
METHODS: BC patients from 54 BRCA1 and BRCA2-negative families with elevated BC risk and 120 matched controls were considered for germline DNA whole exome sequencing. Rare variants identified in the exome and in a virtual panel of cancer-associated genes [492 genes associated with different types of (hereditary) cancer] were compared between BC patients and controls. Nonsense, frame-shift indels and splice-site variants (strong protein-damaging variants, called PDAVs later on) observed in BC patients within the genes of the panel, which we estimated to possess the highest probability to predispose to BC, were further validated using an alternative sequencing procedure.
RESULTS: Exome- and cancer-associated gene panel-wide variant analysis show that there is no significant difference in the average number of rare variants found in BC patients compared to controls. However, the genes in the cancer-associated gene panel with nonsense variants were more than two-fold over-represented in women with BC and commonly involved in the DNA double-strand break repair process. Approximately 44% (24 of 54) of BC patients harbored 31 PDAVs, of which 11 were novel. These variants were found in genes associated with known or suspected BC predisposition (PALB2, BARD1, CHEK2, RAD51C and FANCA) or in predisposing genes linked to other cancer types but not well-studied in the context of familial BC (EXO1, RECQL4, CCNH, MUS81, TDP1, DCLRE1A, DCLRE1C, PDE11A and RINT1) and genes associated with different hereditary syndromes but not yet clearly associated with familial cancer syndromes (ABCC11, BBS10, CD96, CYP1A1, DHCR7, DNAH11, ESCO2, FLT4, HPS6, MYH8, NME8 and TTC8). Exome-wide, only a few genes appeared to be enriched for PDAVs in the familial BC patients compared to controls.
CONCLUSIONS: We have identified a series of novel candidate BC predisposition variants/genes. These variants/genes should be further investigated in larger cohorts/case-control studies. Other studies including co-segregation analyses in affected families, locus-specific loss of heterozygosity and functional studies should shed further light on their relevance for BC risk.

Wang L, Wang H, Wang T, et al.
Analysis of polymorphisms in genes associated with the FA/BRCA pathway in three patients with multiple primary malignant neoplasms.
Artif Cells Nanomed Biotechnol. 2019; 47(1):1101-1112 [PubMed] Related Publications
Cases of more than three primary cancers are very rare. This study analyzed the genetic susceptibility of gene polymorphisms in three patients with multiple primary malignant neoplasms and examined the possible pathogenesis. The clinical data and whole genome sequence of three patients (1 with 5 primary cancers, 1 with 4 primary cancers, and 1 with 3 primary cancers) were aligned with a series of databases. We found the three patients contained a total of seven types of malignant tumours (endometrial cancer, ovarian cancer, breast cancer, colon cancer, ureter cancer, bladder cancer and kidney cancer). It was found that the varied genes in Patient 1 (5 primary cancers) were BRIP1, FANCG, NBN, AXIN2, SRD5A2, and CEBPA. Patient 2 (4 primary cancers) had variations in the following genes: BMPR1A, FANCD2, MLH3, BRCA2, and FANCM. Patient 3 (3 primary cancers) had variations in the following genes: MEN1, ATM, MSH3, BRCA1, FANCL, CEBPA, and FANCA. String software was used to analyze the KEGG pathway of the variations in these three samples, which revealed that the genes are involved in the Fanconi anaemia pathway. Defects in DNA damage repair may be one of the causes of multiple primary cancers.

Malacaria E, Pugliese GM, Honda M, et al.
Rad52 prevents excessive replication fork reversal and protects from nascent strand degradation.
Nat Commun. 2019; 10(1):1412 [PubMed] Article available free on PMC after 01/07/2020 Related Publications
Stabilisation of stalled replication forks prevents excessive fork reversal and their pathological degradation, which can undermine genome integrity. Here we investigate a physiological role of RAD52 at stalled replication forks by using human cell models depleted of RAD52, a specific small-molecule inhibitor of the RAD52-ssDNA interaction, in vitro and single-molecule analyses. We demonstrate that RAD52 prevents excessive degradation of reversed replication forks by MRE11. Mechanistically, RAD52 binds to the stalled replication fork, promotes its occlusion and counteracts loading of SMARCAL1 in vitro and in vivo. Loss of the RAD52 function results in a slightly-defective replication restart, persistence of under-replicated regions and chromosome instability. Moreover, the RAD52-inhibited cells rely on RAD51 for completion of replication and viability upon replication arrest. Collectively, our data suggest an unexpected gatekeeper mechanism by which RAD52 limits excessive remodelling of stalled replication forks, thus indirectly assisting RAD51 and BRCA2 in protecting forks from unscheduled degradation and preventing genome instability.

Lheureux S, Gourley C, Vergote I, Oza AM
Epithelial ovarian cancer.
Lancet. 2019; 393(10177):1240-1253 [PubMed] Related Publications
Epithelial ovarian cancer generally presents at an advanced stage and is the most common cause of gynaecological cancer death. Treatment requires expert multidisciplinary care. Population-based screening has been ineffective, but new approaches for early diagnosis and prevention that leverage molecular genomics are in development. Initial therapy includes surgery and adjuvant therapy. Epithelial ovarian cancer is composed of distinct histological subtypes with unique genomic characteristics, which are improving the precision and effectiveness of therapy, allowing discovery of predictors of response such as mutations in breast cancer susceptibility genes BRCA1 and BRCA2, and homologous recombination deficiency for DNA damage response pathway inhibitors or resistance (cyclin E1). Rapidly evolving techniques to measure genomic changes in tumour and blood allow for assessment of sensitivity and emergence of resistance to therapy, and might be accurate indicators of residual disease. Recurrence is usually incurable, and patient symptom control and quality of life are key considerations at this stage. Treatments for recurrence have to be designed from a patient's perspective and incorporate meaningful measures of benefit. Urgent progress is needed to develop evidence and consensus-based treatment guidelines for each subgroup, and requires close international cooperation in conducting clinical trials through academic research groups such as the Gynecologic Cancer Intergroup.

Latest Publications: BRCA2 (cancer-related)

Golan T, Hammel P, Reni M, et al.
Maintenance Olaparib for Germline
N Engl J Med. 2019; 381(4):317-327 [PubMed] Related Publications
BACKGROUND: Patients with a germline
METHODS: We conducted a randomized, double-blind, placebo-controlled, phase 3 trial to evaluate the efficacy of olaparib as maintenance therapy in patients who had a germline
RESULTS: Of the 3315 patients who underwent screening, 154 underwent randomization and were assigned to a trial intervention (92 to receive olaparib and 62 to receive placebo). The median progression-free survival was significantly longer in the olaparib group than in the placebo group (7.4 months vs. 3.8 months; hazard ratio for disease progression or death, 0.53; 95% confidence interval [CI], 0.35 to 0.82; P = 0.004). An interim analysis of overall survival, at a data maturity of 46%, showed no difference between the olaparib and placebo groups (median, 18.9 months vs. 18.1 months; hazard ratio for death, 0.91; 95% CI, 0.56 to 1.46; P = 0.68). There was no significant between-group difference in health-related quality of life, as indicated by the overall change from baseline in the global quality-of-life score (on a 100-point scale, with higher scores indicating better quality of life) based on the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (between-group difference, -2.47 points; 95% CI, -7.27 to 2.33). The incidence of grade 3 or higher adverse events was 40% in the olaparib group and 23% in the placebo group (between-group difference, 16 percentage points; 95% CI, -0.02 to 31); 5% and 2% of the patients, respectively, discontinued the trial intervention because of an adverse event.
CONCLUSIONS: Among patients with a germline

Stasenko M, Cybulska P, Feit N, et al.
Brain metastasis in epithelial ovarian cancer by BRCA1/2 mutation status.
Gynecol Oncol. 2019; 154(1):144-149 [PubMed] Article available free on PMC after 01/07/2020 Related Publications
OBJECTIVE: To evaluate clinical outcomes of patients with BRCA-associated ovarian cancer who developed brain metastases (BM).
METHODS: Patients with epithelial ovarian, fallopian tube, and primary peritoneal cancer (EOC) and BM, treated at a single institution from 1/1/2008-7/1/2018, were identified from two institutional databases. Charts and medical records were retrospectively reviewed for clinical characteristics and germline BRCA mutation status. Appropriate statistics were used.
RESULTS: Of 3649 patients with EOC, 91 had BM (2.5%). Germline mutation status was available for 63 (69%) cases; 21 (35%) of these harbored a BRCA1/2 mutation (15 BRCA1, 6 BRCA2). Clinical characteristics were similar between groups. BM were diagnosed at a median of 31 months (95% CI, 22.6-39.4) in BRCA-mutated (mBRCA) and 32 months (95% CI, 23.7-40.3) in wild-type BRCA (wtBRCA) (p = 0.78) patients. Brain metastases were the only evidence of disease at time of BM diagnoses in 48% (n = 10) mBRCA and 19% (n = 8) wtBRCA (p = 0.02) patients. There was no difference in treatment of BM by mutation status (p = 0.84). Survival from time of BM diagnosis was 29 months (95%CI, 15.5-42.5) in mBRCA and 9 months (95% CI, 5.5-12.5) in wtBRCA patients, with an adjusted hazard ratio (HR) of 0.53, p = 0.09; 95% CI, 0.25-1.11. HR was adjusted for presence of systemic disease at time of BM diagnosis.
CONCLUSION: This is the largest study to date comparing outcomes in patients with EOC and BM by mutation status. mBRCA patients were more likely to have isolated BM, which may be a factor in their long survival. This supports the pursuit of aggressive treatment for mBRCA EOC patients with BM. Additional studies examining the correlation of BRCA mutational status with BM are warranted.

Toss A, Molinaro E, Sammarini M, et al.
Hereditary ovarian cancers: state of the art.
Minerva Med. 2019; 110(4):301-319 [PubMed] Related Publications
The identification of a mutation in ovarian cancer (OC) predisposition genes plays a crucial role in the management of cancer prevention, diagnosis, and treatment. In healthy carriers, the detection of a specific mutation might justify more intensive and personalised surveillance programmes, chemopreventive measures, and prophylactic surgeries. Moreover, the identification of a mutation in affected OC patients might provide fundamental knowledge of the tumour pathogenesis, thus guiding treatment choices. This is a comprehensive review of the molecular pathways involved in the pathogenesis of hereditary ovarian cancers, the clinical-pathological features of these tumours, and the potential implications for their prevention and clinical management.

Tomao F, Musacchio L, Di Mauro F, et al.
Is BRCA mutational status a predictor of platinum-based chemotherapy related hematologic toxicity in high-grade serous ovarian cancer patients?
Gynecol Oncol. 2019; 154(1):138-143 [PubMed] Related Publications
OBJECTIVE: To evaluate hematologic adverse effect profiles associated with frontline platinum-based chemotherapy in ovarian cancer patients according to BRCA 1/2 mutational status.
METHODS: Patients with high-grade serous ovarian cancer and a known BRCA mutational status who received in frontline 6 cycles of Carboplatin (AUC 5) plus Paclitaxel 175 mg/mq were retrospectively selected from our databases. Hematologic toxicity profiles of BRCA mutated patients were compared to non-mutated patients, according to EORTC Common Terminology Criteria for Adverse Events (CTCAE_4.02).
RESULTS: Totally, 176 women of whom 58 (33%) were BRCA1/2 mutation carriers - 40 BRCA1 (69%) and 18 (31%) BRCA2 mutations carriers - and 118 (67%) non-carriers were identified. A significant higher frequency of thrombocytopenia (24% vs 5%; p < 0.001), anemia (21% vs 7%; p = 0.006) and neutropenia (62% vs 27%; p ≤0.001) was observed in BRCA mutated patients, resulting in a higher percentage of granulocyte-colony stimulating growth factors injection (12% versus 1%, p < 0.001) and dose delay (19% versus 27%, p = 0.005). The multivariate analysis confirmed that granulocyte-colony stimulating growth factors injection and dose delay were statistically significantly more frequent in BRCA mutated patients (OR 2.567, 95% CI 1.136-5.798, p = 0.035; OR 3.860, 95% CI 1.098-13.570, p = 0.023). Finally, the total number of hematologic adverse events compared between the two groups of patients during the entire treatment period showed a substantial higher rate of hematologic adverse events in BRCA mutated population.
CONCLUSIONS: Germline BRCA 1/2 mutations are associated with a higher hematologic toxicity in patients with ovarian cancer who underwent platinum-based chemotherapy.

Zakrzewski F, Gieldon L, Rump A, et al.
Targeted capture-based NGS is superior to multiplex PCR-based NGS for hereditary BRCA1 and BRCA2 gene analysis in FFPE tumor samples.
BMC Cancer. 2019; 19(1):396 [PubMed] Article available free on PMC after 01/07/2020 Related Publications
BACKGROUND: With the introduction of Olaparib treatment for BRCA-deficient recurrent ovarian cancer, testing for somatic and/or germline mutations in BRCA1/2 genes in tumor tissues became essential for treatment decisions. In most cases only formalin-fixed paraffin-embedded (FFPE) samples, containing fragmented and chemically modified DNA of minor quality, are available. Thus, multiplex PCR-based sequencing is most commonly applied in routine molecular testing, which is predominantly focused on the identification of known hot spot mutations in oncogenes.
METHODS: We compared the overall performance of an adjusted targeted capture-based enrichment protocol and a multiplex PCR-based approach for calling of pathogenic SNVs and InDels using DNA extracted from 13 FFPE tissue samples. We further applied both strategies to seven blood samples and five matched FFPE tumor tissues of patients with known germline exon-spanning deletions and gene-wide duplications in BRCA1/2 to evaluate CNV detection based solely on panel NGS data. Finally, we analyzed DNA from FFPE tissues of 11 index patients from families suspected of having hereditary breast and ovarian cancer, of whom no blood samples were available for testing, in order to identify underlying pathogenic germline BRCA1/2 mutations.
RESULTS: The multiplex PCR-based protocol produced inhomogeneous coverage among targets of each sample and between samples as well as sporadic amplicon drop out, leading to insufficiently or non-covered nucleotides, which subsequently hindered variant detection. This protocol further led to detection of PCR-artifacts that could easily have been misinterpreted as pathogenic mutations. No such limitations were observed by application of an adjusted targeted capture-based protocol, which allowed for CNV calling with 86% sensitivity and 100% specificity. All pathogenic CNVs were confirmed in the five matched FFPE tumor samples from patients carrying known pathogenic germline mutations and we additionally identified somatic loss of the second allele in BRCA1/2. Furthermore we detected pathogenic BRCA1/2 variants in four the eleven FFPE samples from patients of whom no blood was available for analysis.
CONCLUSIONS: We demonstrate that an adjusted targeted capture-based enrichment protocol is superior to commonly applied multiplex PCR-based protocols for reliable BRCA1/2 variant detection, including CNV-detection, using FFPE tumor samples.

Gulhan DC, Lee JJ, Melloni GEM, et al.
Detecting the mutational signature of homologous recombination deficiency in clinical samples.
Nat Genet. 2019; 51(5):912-919 [PubMed] Related Publications
Mutations in BRCA1 and/or BRCA2 (BRCA1/2) are the most common indication of deficiency in the homologous recombination (HR) DNA repair pathway. However, recent genome-wide analyses have shown that the same pattern of mutations found in BRCA1/2-mutant tumors is also present in several other tumors. Here, we present a new computational tool called Signature Multivariate Analysis (SigMA), which can be used to accurately detect the mutational signature associated with HR deficiency from targeted gene panels. Whereas previous methods require whole-genome or whole-exome data, our method detects the HR-deficiency signature even from low mutation counts, by using a likelihood-based measure combined with machine-learning techniques. Cell lines that we identify as HR deficient show a significant response to poly (ADP-ribose) polymerase (PARP) inhibitors; patients with ovarian cancer whom we found to be HR deficient show a significantly longer overall survival with platinum regimens. By enabling panel-based identification of mutational signatures, our method substantially increases the number of patients that may be considered for treatments targeting HR deficiency.

Chen J, Chen J, He F, et al.
Design of a Targeted Sequencing Assay to Detect Rare Mutations in Circulating Tumor DNA.
Genet Test Mol Biomarkers. 2019; 23(4):264-269 [PubMed] Related Publications
BACKGROUND: Qualitative and quantitative detection of circulating tumor DNA (ctDNA) is a liquid biopsy technology used for early cancer diagnosis. However, the plasma ctDNA content is extremely low, so it is difficult to detect somatic mutations of tumors using conventional sequencing methods. Target region sequencing (TRS) technology, through enrichment of the target genomic region followed by next generation sequencing, overcomes this challenge and has been widely used in ctDNA sequencing.
METHODS: We designed a ctDNA sequencing panel to capture 128 tumor genes, and tested the performance of the panel by running TRS for ctDNA of a clear cell renal cell carcinoma (ccRCC) patient and 12 breast cancer patients.
RESULTS: TRS using the new ctDNA panel at more than 500 × coverage depth achieved almost the same accuracy as traditional whole-exome sequencing (WES). PBRM1 p.L641V was detected in the plasma sample of the ccRCC patient with an allele frequency of 0.2%. The ctDNA of 12 breast cancer patients was sequenced at a depth of 500-fold, achieving 99.89% coverage; 34 genes were detected with mutations, including the drug target genes BRCA2, PTEN, TP53, APC, KDR, and NOTCH2.
CONCLUSIONS: This TRS new ctDNA panel can be used to detect mutations in cell-free DNA from multiple types of cancer.

Gröschel S, Hübschmann D, Raimondi F, et al.
Defective homologous recombination DNA repair as therapeutic target in advanced chordoma.
Nat Commun. 2019; 10(1):1635 [PubMed] Article available free on PMC after 01/07/2020 Related Publications
Chordomas are rare bone tumors with few therapeutic options. Here we show, using whole-exome and genome sequencing within a precision oncology program, that advanced chordomas (n = 11) may be characterized by genomic patterns indicative of defective homologous recombination (HR) DNA repair and alterations affecting HR-related genes, including, for example, deletions and pathogenic germline variants of BRCA2, NBN, and CHEK2. A mutational signature associated with HR deficiency was significantly enriched in 72.7% of samples and co-occurred with genomic instability. The poly(ADP-ribose) polymerase (PARP) inhibitor olaparib, which is preferentially toxic to HR-incompetent cells, led to prolonged clinical benefit in a patient with refractory chordoma, and whole-genome analysis at progression revealed a PARP1 p.T910A mutation predicted to disrupt the autoinhibitory PARP1 helical domain. These findings uncover a therapeutic opportunity in chordoma that warrants further exploration, and provide insight into the mechanisms underlying PARP inhibitor resistance.

Shahi RB, De Brakeleer S, Caljon B, et al.
Identification of candidate cancer predisposing variants by performing whole-exome sequencing on index patients from BRCA1 and BRCA2-negative breast cancer families.
BMC Cancer. 2019; 19(1):313 [PubMed] Article available free on PMC after 01/07/2020 Related Publications
BACKGROUND: In the majority of familial breast cancer (BC) families, the etiology of the disease remains unresolved. To identify missing BC heritability resulting from relatively rare variants (minor allele frequency ≤ 1%), we have performed whole exome sequencing followed by variant analysis in a virtual panel of 492 cancer-associated genes on BC patients from BRCA1 and BRCA2 negative families with elevated BC risk.
METHODS: BC patients from 54 BRCA1 and BRCA2-negative families with elevated BC risk and 120 matched controls were considered for germline DNA whole exome sequencing. Rare variants identified in the exome and in a virtual panel of cancer-associated genes [492 genes associated with different types of (hereditary) cancer] were compared between BC patients and controls. Nonsense, frame-shift indels and splice-site variants (strong protein-damaging variants, called PDAVs later on) observed in BC patients within the genes of the panel, which we estimated to possess the highest probability to predispose to BC, were further validated using an alternative sequencing procedure.
RESULTS: Exome- and cancer-associated gene panel-wide variant analysis show that there is no significant difference in the average number of rare variants found in BC patients compared to controls. However, the genes in the cancer-associated gene panel with nonsense variants were more than two-fold over-represented in women with BC and commonly involved in the DNA double-strand break repair process. Approximately 44% (24 of 54) of BC patients harbored 31 PDAVs, of which 11 were novel. These variants were found in genes associated with known or suspected BC predisposition (PALB2, BARD1, CHEK2, RAD51C and FANCA) or in predisposing genes linked to other cancer types but not well-studied in the context of familial BC (EXO1, RECQL4, CCNH, MUS81, TDP1, DCLRE1A, DCLRE1C, PDE11A and RINT1) and genes associated with different hereditary syndromes but not yet clearly associated with familial cancer syndromes (ABCC11, BBS10, CD96, CYP1A1, DHCR7, DNAH11, ESCO2, FLT4, HPS6, MYH8, NME8 and TTC8). Exome-wide, only a few genes appeared to be enriched for PDAVs in the familial BC patients compared to controls.
CONCLUSIONS: We have identified a series of novel candidate BC predisposition variants/genes. These variants/genes should be further investigated in larger cohorts/case-control studies. Other studies including co-segregation analyses in affected families, locus-specific loss of heterozygosity and functional studies should shed further light on their relevance for BC risk.

Wang L, Wang H, Wang T, et al.
Analysis of polymorphisms in genes associated with the FA/BRCA pathway in three patients with multiple primary malignant neoplasms.
Artif Cells Nanomed Biotechnol. 2019; 47(1):1101-1112 [PubMed] Related Publications
Cases of more than three primary cancers are very rare. This study analyzed the genetic susceptibility of gene polymorphisms in three patients with multiple primary malignant neoplasms and examined the possible pathogenesis. The clinical data and whole genome sequence of three patients (1 with 5 primary cancers, 1 with 4 primary cancers, and 1 with 3 primary cancers) were aligned with a series of databases. We found the three patients contained a total of seven types of malignant tumours (endometrial cancer, ovarian cancer, breast cancer, colon cancer, ureter cancer, bladder cancer and kidney cancer). It was found that the varied genes in Patient 1 (5 primary cancers) were BRIP1, FANCG, NBN, AXIN2, SRD5A2, and CEBPA. Patient 2 (4 primary cancers) had variations in the following genes: BMPR1A, FANCD2, MLH3, BRCA2, and FANCM. Patient 3 (3 primary cancers) had variations in the following genes: MEN1, ATM, MSH3, BRCA1, FANCL, CEBPA, and FANCA. String software was used to analyze the KEGG pathway of the variations in these three samples, which revealed that the genes are involved in the Fanconi anaemia pathway. Defects in DNA damage repair may be one of the causes of multiple primary cancers.

Horvat N, Veeraraghavan H, Pelossof RA, et al.
Radiogenomics of rectal adenocarcinoma in the era of precision medicine: A pilot study of associations between qualitative and quantitative MRI imaging features and genetic mutations.
Eur J Radiol. 2019; 113:174-181 [PubMed] Article available free on PMC after 01/04/2020 Related Publications
OBJECTIVE: To investigate associations between genetic mutations and qualitative as well as quantitative features on MRI in rectal adenocarcinoma at primary staging.
METHODS: In this retrospective study, patients with rectal adenocarcinoma, genome sequencing, and pretreatment rectal MRI were included. Statistical analysis was performed to evaluate associations between qualitative features obtained from subjective evaluation of rectal MRI and gene mutations as well as between quantitative textural features and gene mutations. For the qualitative evaluation, Fisher's Exact test was used to analyze categorical associations and Wilcoxon Rank Sum test was used for continuous clinical variables. For the quantitative evaluation, we performed manual segmentation of T2-weighted images for radiomics-based quantitative image analysis. Thirty-four texture features consisting of first order intensity histogram-based features (n = 4), second order Haralick textures (n = 5), and Gabor-edge based Haralick textures were computed at two different orientations. Consensus clustering was performed with 34 computed texture features using the K-means algorithm with Euclidean distance between the texture features. The clusters resulting from the algorithm were then used to enumerate the prevalence of gene mutations in those clusters.
RESULTS: In 65 patients, 45 genes were mutated in more than 3/65 patients (5%) and were included in the statistical analysis. Regarding qualitative imaging features, on univariate analysis, tumor location was significantly associated with APC (p = 0.032) and RASA1 mutation (p = 0.032); CRM status was significantly associated with ATM mutation (p = 0.021); and lymph node metastasis was significantly associated with BRCA2 (p = 0.046) mutation. However, these associations were not significant after adjusting for multiple comparisons. Regarding quantitative imaging features, Cluster C1 had tumors with higher mean Gabor edge intensity compared with cluster C2 (θ = 0°, p = 0.018; θ = 45°, p = 0.047; θ = 90°, p = 0.037; cluster C3 (θ = 0°, p = 0.18; θ = 45°, p = 0.1; θ = 90°, p = 0.052), and cluster C4 (θ = 0°, p = 0.016; θ = 45°, p = 0.033; θ = 90°, p = 0.014) suggesting that the cluster C1 had tumors with more distinct edges or heterogeneous appearance compared with other clusters.
CONCLUSIONS: Although this preliminary study showed promising associations between quantitative features and genetic mutations, it did not show any correlation between qualitative features and genetic mutations. Further studies with larger sample size are warranted to validate our preliminary data.

Lheureux S, Gourley C, Vergote I, Oza AM
Epithelial ovarian cancer.
Lancet. 2019; 393(10177):1240-1253 [PubMed] Related Publications
Epithelial ovarian cancer generally presents at an advanced stage and is the most common cause of gynaecological cancer death. Treatment requires expert multidisciplinary care. Population-based screening has been ineffective, but new approaches for early diagnosis and prevention that leverage molecular genomics are in development. Initial therapy includes surgery and adjuvant therapy. Epithelial ovarian cancer is composed of distinct histological subtypes with unique genomic characteristics, which are improving the precision and effectiveness of therapy, allowing discovery of predictors of response such as mutations in breast cancer susceptibility genes BRCA1 and BRCA2, and homologous recombination deficiency for DNA damage response pathway inhibitors or resistance (cyclin E1). Rapidly evolving techniques to measure genomic changes in tumour and blood allow for assessment of sensitivity and emergence of resistance to therapy, and might be accurate indicators of residual disease. Recurrence is usually incurable, and patient symptom control and quality of life are key considerations at this stage. Treatments for recurrence have to be designed from a patient's perspective and incorporate meaningful measures of benefit. Urgent progress is needed to develop evidence and consensus-based treatment guidelines for each subgroup, and requires close international cooperation in conducting clinical trials through academic research groups such as the Gynecologic Cancer Intergroup.

Blok F, Dasgupta S, Dinjens WNM, et al.
Retrospective study of a 16 year cohort of BRCA1 and BRCA2 carriers presenting for RRSO: Prevalence of invasive and in-situ carcinoma, with follow-up.
Gynecol Oncol. 2019; 153(2):326-334 [PubMed] Related Publications
OBJECTIVES: Carriers of BRCA1 and BRCA2 mutations are at increased risk of high grade serous carcinoma and are therefore offered risk-reducing salpingo-oophorectomy (RRSO) by 40-45 years. Most of these carcinomas are believed to arise in the fallopian tube from serous tubal intraepithelial carcinoma (STIC). We conducted a retrospective study on the prevalence of high grade serous carcinoma and STIC in BRCA1/2 carriers presenting for RRSO, and their follow-up.
METHODS: Consecutive BRCA1/2 carriers presenting for an RRSO at Erasmus MC (2000-2016) were studied. SEE-FIM pathology protocol was followed from 2010 onwards. For the cases with carcinoma and/or STIC, the histology was reviewed and immunohistochemistry (p53 & MIB-1) was performed. Next Generation Targeted Sequencing (NGTS) for TP53 mutation was used to establish clonality in 2 cases.
RESULTS: Of the 527 included patients, 68% were BRCA1, 31.6% were BRCA2, and 0.4% carried both mutations. The prevalence of high grade serous carcinoma was 2.3% (12/527); 59% of these were of tubal origin. High grade serous carcinoma was more common in patients operated on after the recommended age (p = 0.03). Isolated STIC was present in 0.8% (4/527). Two BRCA1 carriers with isolated STIC at RRSO developed peritoneal serous carcinoma >7 years later. Identical TP53 mutations in the peritoneal serous carcinoma and the preceding STIC established their clonal origin.
CONCLUSIONS: High grade serous carcinoma is more common in BRCA1/2 carriers presenting for RRSO after the recommended age, and is more often of tubal origin. Longer follow up of patients with STIC at RRSO should be considered.

Ratner E, Bala M, Louie-Gao M, et al.
Increased risk of brain metastases in ovarian cancer patients with BRCA mutations.
Gynecol Oncol. 2019; 153(3):568-573 [PubMed] Related Publications
PURPOSE: To estimate the risk for brain metastases in patients with ovarian cancer using real-world data, and assess whether BRCA mutations increase that risk.
METHODS: This retrospective study included 4515 patients diagnosed with ovarian cancer between January 1, 2011, and January 31, 2018, from the Flatiron Health database, a longitudinal, demographically, and geographically diverse database derived from electronic health records in the United States.
RESULTS: Forty-six (1%) patients were diagnosed with brain metastases after being diagnosed with ovarian cancer. Of 4515 patients with ovarian cancer, 10% had a known BRCA mutation, 37% had BRCA wildtype (BRCAwt), and the BRCA status of the remaining 51% was unknown/untested. Brain metastases were observed in 3% of patients with BRCA mutations compared with 0.6% of those with BRCAwt. The Kaplan-Meier estimate for the proportion of patients with brain metastases within 5 years of diagnosis was 5.7% in the population with BRCA mutations compared with 1.4% in those with BRCAwt (hazard ratio 4.44; 95% confidence interval, 1.97, 10.00; P < 0.0001). These data demonstrate that patients with a BRCA mutation had a significantly higher risk for brain metastases than those without.
CONCLUSION: Despite being a rare manifestation of ovarian cancer, the possibility of developing brain metastases should be considered in these patients, especially in patients with a BRCA mutation. The availability of new therapeutic options that may prolong overall survival and may not cross the blood-brain barrier could also lead to an increase in brain metastases in patients with ovarian cancer.

Foote JR, Secord AA, Liang MI, et al.
Targeted composite value-based endpoints in platinum-sensitive recurrent ovarian cancer.
Gynecol Oncol. 2019; 152(3):445-451 [PubMed] Related Publications
OBJECTIVES: FDA-approved treatments for platinum-sensitive recurrent ovarian cancer (PSROC) include bevacizumab and PARP inhibitors (PARPi); clinical decisions regarding therapy must be made prior to initiating chemotherapy. Using the American Society of Clinical Oncology (ASCO) and European Society of Medical Oncology (ESMO) value frameworks, we assessed relative values of concurrent/maintenance biologic therapies in PSROC.
METHODS: Value scores were calculated for key maintenance therapies based on randomized controlled trials: bevacizumab (OCEANS, GOG 213); olaparib (Study 19, SOLO2); niraparib (NOVA); rucaparib (ARIEL3). Personalized value scorecards were constructed for patients with germline/somatic-BRCA mutations, homologous recombination deficiency (HRD), and wild-type BRCA (wBRCA). ASCO value scores assess clinical benefit, toxicity, long-term survival, symptom palliation, treatment-free interval, and quality of life (QOL). ESMO value scores assess clinical benefit, toxicity, and QOL.
RESULTS: ASCO scores were highest for maintenance PARPi in germline/somatic-BRCA mutation cohorts: olaparib (SOLO2) = 47, (Study 19) = 62; niraparib = 50; rucaparib = 54. HRD cohorts had slightly lower scores: niraparib = 46; rucaparib = 37. wBRCA cohorts had the lowest scores: niraparib = 26; rucaparib = 26; and olaparib (Study 19) = 32, as did patients receiving bevacizumab (OCEANS) = 35, (GOG 213) = 26. ESMO scores demonstrated high-value for maintenance PARPi in germline/somatic-BRCA mutation cohorts and low-value for bevacizumab and PARPi in wBRCA cohorts.
CONCLUSIONS: The value of maintenance PARPi therapy depends heavily on BRCA status, with the highest value scores in germline/somatic-BRCA mutation cohorts. Personalized value scorecards provide a visual aid to assess the harm-benefit balance of maintenance PARPi for PSROC.

Torrisi R, Zuradelli M, Agostinetto E, et al.
Platinum salts in the treatment of BRCA-associated breast cancer: A true targeted chemotherapy?
Crit Rev Oncol Hematol. 2019; 135:66-75 [PubMed] Related Publications
Germline pathogenic mutations in breast cancer (BC) susceptibility genes (gBRCA1/2) are the most frequent inherited alterations in BC and are involved in the homologous recombination pathway, the principal mechanism of DNA double strand break repair. Platinum salts which act as DNA cross-linking agents are therefore more likely to be active in BRCA-deficient tumors. Women with gBRCA-associated tumors, particularly with triple negative BC, receiving neoadjuvant platinum containing regimens achieved higher pCR rates as compared to wild-type BC. However in two large randomized trials the addition of carboplatin significantly increased pCR rate only in wild-type tumors. On the contrary, the randomized TNT trial showed a significant benefit for carboplatin vs docetaxel in terms of response rate and PFS specifically in patients with advanced gBRCA -associated tumors. Biomarkers of sensitivity to DNA damaging agents beyond gBRCA mutations predicting activity of platinum salts have been proposed and should be validated prospectively.

Vallard A, Magné N, Guy JB, et al.
Is breast-conserving therapy adequate in BRCA 1/2 mutation carriers? The radiation oncologist's point of view.
Br J Radiol. 2019; 92(1097):20170657 [PubMed] Article available free on PMC after 01/05/2020 Related Publications
Breast conserving therapy (BCT) is currently a recognized alternative to mastectomy for early BC patients. However, the therapeutic index of BCT was considered controversial for decades in BRCA1/2 mutation carriers. The aim of the present review was to investigate the outcome of mutation carriers undergoing BCT regarding local and distant endpoints. A short review was performed from the point of view of the radiation oncologist. Only retrospective data were available regarding local outcome assessment. They generated conflicting results. In studies with limited follow-up, BCT did not increase the risk of local recurrence in BRCA1/2 mutation carriers

Kim M, Suh DH, Lee KH, et al.
Major clinical research advances in gynecologic cancer in 2018.
J Gynecol Oncol. 2019; 30(2):e18 [PubMed] Article available free on PMC after 01/05/2020 Related Publications
Nineteen topics were selected as major clinical research advances in gynecologic oncology in 2018. For cervical cancer, the importance of human papillomavirus (HPV) testing alone as primary cervical cancer screening method and negative survival impact of minimally invasive surgery in early-stage cervical cancer were addressed. For ovarian cancer, cost-effectiveness of genetic testing to prevent cancer, use of analgesics and oral pill to reduce cancer risk, efficacy of secondary cytoreductive surgery and hyperthermic intraperitoneal chemotherapy, update in the use of poly (ADP-ribose) polymerase inhibitor, and efficacy of anti-angiogenic targeted treatments, including bevacizumab and tyrosine kinase inhibitors, were reviewed. For corpus cancer, sentinel lymph node mapping technique, adjuvant therapy in high-risk endometrial cancer (PORTEC-3), and targeted therapy in recurrent disease were covered. For the field of radiation oncology, survival outcomes of chemoradiation compared with chemotherapy alone in metastatic cervical cancer and new findings regarding the use of neoadjuvant chemotherapy in locally advanced cervical cancer were introduced. Lastly, for breast cancer, the use of talazoparib in patients with germline

Sridharan DM, Enerio S, Wang C, et al.
Genetic variation and radiation quality impact cancer promoting cellular phenotypes in response to HZE exposure.
Life Sci Space Res (Amst). 2019; 20:101-112 [PubMed] Related Publications
There exists a wide degree of genetic variation within the normal human population which includes disease free individuals with heterozygote defects in major DNA repair genes. A lack of understanding of how this genetic variation impacts cellular phenotypes that inform cancer risk post heavy ion exposure poses a major limitation in developing personalized cancer risk assessment astronauts. We initiated a pilot study with Human Mammary Epithelial Cell strains (HMEC) derived from wild type, a p16 silenced derivative of wild type, and various genetic variants that were heterozygote for DNA repair genes; BRCA1, BRCA2 and ATM. Cells strains were exposed to different high and low LET radiation qualities to generate both simple and complex lesions and centrosome aberrations were examined as a surrogate marker of genomic instability and cancer susceptibility post different exposures. Our results indicate that centrosome aberration frequency is higher in the genetic variants under study. The aberration frequency increases with dose, complexity of the lesion generated by different radiation qualities and age of the individual. This increase in genomic instability correlates with elevated check-point activation post radiation exposure. These studies suggest that the influence of individual genetics on cell cycle regulation could modify the degree of early genomic instability in response to complex lesions and potentially define cancer predisposition in response to HZE exposure. These results will have significant implications in estimating cancer susceptibility in genetically variant individuals exposed to HZE particles.

Kuo IY, Huang YL, Lin CY, et al.
SOX17 overexpression sensitizes chemoradiation response in esophageal cancer by transcriptional down-regulation of DNA repair and damage response genes.
J Biomed Sci. 2019; 26(1):20 [PubMed] Article available free on PMC after 01/05/2020 Related Publications
BACKGROUND: Prognosis of esophageal squamous cell carcinoma (ESCC) patients is poor and the concurrent chemoradiation therapy (CCRT) provided to ESCC patients often failed due to resistance. Therefore, development of biomarkers for predicting CCRT response is immensely important. In this study, we evaluated the predicting value of SRY (sex determining region Y)-box 17 (SOX17) protein during CCRT and its dysregulation of transcriptional targets in CCRT resistance in ESCC.
METHODS: Pyrosequencing methylation, RT-qPCR and immunohistochemistry assays were performed to examine the DNA methylation, mRNA expression and protein expression levels of SOX17 in endoscopic biopsy from a total of 70 ESCC patients received CCRT. Cell proliferation, clonogenic survival and xenograft growth were used to confirm the sensitization of ESCC cell line KYSE510 in response to cisplatin, radiation or CCRT treatment by SOX17 overexpression in vitro and in vivo. Luciferase activity, RT-qPCR and ChIP-qPCR assays were conducted to examine transcription regulation of SOX17 in KYSE510 parental, KYSE510 radio-resistant cells and their derived xenografts.
RESULTS: High DNA methylation coincided with low mRNA and protein expression levels of SOX17 in pre-treatment endoscopic biopsy from ESCC patients with poor CCRT response. SOX17 protein expression exhibited a good prediction performance in discriminating poor CCRT responders from good responder. Overexpression of SOX17 sensitized KYSE510 radio-resistant cells to cisplatin, radiation or CCRT treatment in cell and xenograft models. Importantly, SOX17 transcriptionally down-regulated DNA repair and damage response-related genes including BRCA1, BRCA2, RAD51, KU80 DNAPK, p21, SIRT1, NFAT5 and REV3L in KYSE510 radio-resistant cells to achieve the sensitization effect to anti-cancer treatment. Low expression of BRCA1, DNAPK, p21, RAD51 and SIRT1 was confirmed in SOX17 sensitized xenograft tissues derived from radio-resistant ESCC cells.
CONCLUSIONS: Our study reveals a novel mechanism by which SOX17 transcriptionally inactivates DNA repair and damage response-related genes to sensitize ESCC cell or xenograft to CCRT treatment. In addition, we establish a proof-of-concept CCRT prediction biomarker using SOX17 immunohistochemical staining in pre-treatment endoscopic biopsies to identify ESCC patients who are at high risk of CCRT failure and need intensive care.

Manchanda R, Gaba F
A commentary on population genetic testing for primary prevention: changing landscape and the need to change paradigm.
BJOG. 2019; 126(6):686-689 [PubMed] Related Publications
BRCA1/BRCA2 genes were discovered in early 1990s and clinical testing for these has been available since the mid-1990s. National Institute of Health and Care Excellence (NICE) and other international guidelines recommend genetic-testing at a ~10% probability threshold of carrying a BRCA-mutation. A detailed three generation family-history (FH) of cancer is used within complex mathematical models (e.g. BOADICEA, BRCAPRO, Manchester-Scoring-System) or through standardized clinical-criteria to identify individuals who fulfil this probability threshold and can be offered genetic-testing. Identification of unaffected carriers is important given the high risk of cancer in these women and the effective options available for clinical management which can reduce cancer risk, improve outcomes and minimise burden of disease. This article is protected by copyright. All rights reserved.

Manchanda R, Burnell M, Gaba F, et al.
Attitude towards and factors affecting uptake of population-based BRCA testing in the Ashkenazi Jewish population: a cohort study.
BJOG. 2019; 126(6):784-794 [PubMed] Related Publications
OBJECTIVE: To evaluate factors affecting unselected population-based BRCA testing in Ashkenazi Jews (AJ).
DESIGN: Cohort-study set within recruitment to the GCaPPS trial (ISRCTN73338115).
SETTING: North London AJ population.
POPULATION OR SAMPLE: Ashkenazi Jews women/men >18 years, recruited through self-referral.
METHODS: Ashkenazi Jews women/men underwent pre-test counselling for BRCA testing through recruitment clinics (clusters). Consenting individuals provided blood samples for BRCA testing. Data were collected on socio-demographic/family history/knowledge/psychological well-being along with benefits/risks/cultural influences (18-item questionnaire measuring 'attitude'). Four-item Likert-scales analysed initial 'interest' and 'intention-to-test' pre-counselling. Uni- and multivariable logistic regression models evaluated factors affecting uptake/interest/intention to undergo BRCA testing. Statistical inference was based on cluster robust standard errors and joint Wald tests for significance. Item-Response Theory and graded-response models modelled responses to 18-item questionnaire.
MAIN OUTCOME MEASURES: Interest, intention, uptake, attitude towards BRCA testing.
RESULTS: A total of 935 individuals (women = 67%/men = 33%; mean age = 53.8 (SD = 15.02) years) underwent pre-test genetic-counselling. During the pre-counselling, 96% expressed interest in and 60% indicated a clear intention to undergo BRCA testing. Subsequently, 88% opted for BRCA testing. BRCA-related knowledge (P = 0.013) and degree-level education (P = 0.01) were positively and negatively (respectively) associated with intention-to-test. Being married/cohabiting had four-fold higher odds for BRCA testing uptake (P = 0.009). Perceived benefits were associated with higher pre-counselling odds for interest in and intention to undergo BRCA testing. Reduced uncertainty/reassurance were the most important factors contributing to decision-making. Increased importance/concern towards risks/limitations (confidentiality/insurance/emotional impact/inability to prevent cancer/marriage ability/ethnic focus/stigmatisation) were significantly associated with lower odds of uptake of BRCA testing, and discriminated between acceptors and decliners. Male gender/degree-level education (P = 0.001) had weaker correlations, whereas having children showed stronger (P = 0.005) associations with attitudes towards BRCA testing.
CONCLUSIONS: BRCA testing in the AJ population has high acceptability. Pre-test counselling increases awareness of disadvantages/limitations of BRCA testing, influencing final cost-benefit perception and decision-making on undergoing testing.
TWEETABLE ABSTRACT: BRCA testing in Ashkenazi Jews has high acceptability and uptake. Pre-test counselling facilitates informed decision-making.

Barrett R, Neben CL, Zimmer AD, et al.
A scalable, aggregated genotypic-phenotypic database for human disease variation.
Database (Oxford). 2019; 2019 [PubMed] Article available free on PMC after 01/05/2020 Related Publications
Next generation sequencing multi-gene panels have greatly improved the diagnostic yield and cost effectiveness of genetic testing and are rapidly being integrated into the clinic for hereditary cancer risk. With this technology comes a dramatic increase in the volume, type and complexity of data. This invaluable data though is too often buried or inaccessible to researchers, especially to those without strong analytical or programming skills. To effectively share comprehensive, integrated genotypic-phenotypic data, we built Color Data, a publicly available, cloud-based database that supports broad access and data literacy. The database is composed of 50 000 individuals who were sequenced for 30 genes associated with hereditary cancer risk and provides useful information on allele frequency and variant classification, as well as associated phenotypic information such as demographics and personal and family history. Our user-friendly interface allows researchers to easily execute their own queries with filtering, and the results of queries can be shared and/or downloaded. The rapid and broad dissemination of these research results will help increase the value of, and reduce the waste in, scientific resources and data. Furthermore, the database is able to quickly scale and support integration of additional genes and human hereditary conditions. We hope that this database will help researchers and scientists explore genotype-phenotype correlations in hereditary cancer, identify novel variants for functional analysis and enable data-driven drug discovery and development.

Carlson K, Chung A, Mirocha J, et al.
Menopausal Status and Outcomes of BRCA Mutation Carriers with Breast Cancer.
Am Surg. 2018; 84(10):1584-1588 [PubMed] Related Publications
Outcomes based on menopausal status of breast cancer (BC) patients who are BRCA mutations carriers (BRCAm) are not well known. A prospective database identified 88 BRCAm with BC from 2005 to 2015. Of the 88 patients, 68 (77.3%) women were premenopausal (Pre-M) and 20 (22.7%) were postmenopausal (Post-M). In the Pre-M group, 52.9 per cent of patients had triple-negative (TN) BC, whereas in the Post-M group, there were more estrogen receptor +(65%;

Suda K, Nakaoka H, Hata C, et al.
Concurrent isolated retroperitoneal HGSC and STIC defined by somatic mutation analysis: a case report.
Diagn Pathol. 2019; 14(1):17 [PubMed] Article available free on PMC after 01/05/2020 Related Publications
BACKGROUND: Retroperitoneal high-grade serous carcinoma (HGSC) is extremely rare and the origin remains unclear. We present a case of retroperitoneal HGSC and coexisting serous tubal intraepithelial carcinoma (STIC), which is considered as the main origin of ovarian HGSC. We reviewed the available literature and discussed about the origin of this rare disease.
CASE PRESENTATION: A 58-year-old female with a 93 × 65 × 62 mm-solid tumor with a cystic part was located immediately dorsal to the rectum underwent bilateral salpingo-oophorectomy, total abdominal hysterectomy, and en bloc resection of the retroperitoneal tumor together with lower anterior resection of the rectum. Histological diagnosis was retroperitoneal HGSC and STIC at the right fallopian tube. Two deleterious somatic mutations in TP53 and BRCA2 genes were shared between retroperitoneal HGSC and STIC.
CONCLUSIONS: In addition to clinical features in the previous reports, our genetic findings suggest the origin of retroperitoneal HGSC might be STIC.

Lattimore VL, Pearson JF, Morley-Bunker AE, et al.
Quantifying
Int J Mol Sci. 2019; 20(3) [PubMed] Article available free on PMC after 01/05/2020 Related Publications

Suszynska M, Klonowska K, Jasinska AJ, Kozlowski P
Large-scale meta-analysis of mutations identified in panels of breast/ovarian cancer-related genes - Providing evidence of cancer predisposition genes.
Gynecol Oncol. 2019; 153(2):452-462 [PubMed] Related Publications
OBJECTIVE: Germline mutations occurring in the highly penetrant genes BRCA1 and BRCA2 are responsible for only certain cases of familial breast cancer (BC) and ovarian cancer (OC). Thus, the use of NGS multi-gene panel (MGP) testing has recently become very popular.
METHODS: To estimate a reliable BC and OC risk associated with pathogenic variants in the selected candidate BC/OC predisposition genes, a comprehensive meta-analysis of 48 MGP-based studies analyzing BC/OC patients was conducted. The role of 37 genes was evaluated, comparing, in total, the mutation frequency in ~120,000 BC/OC cases and ~120,000 controls, which guaranteed strong statistical support with high confidence for most analyzed genes.
RESULTS: We characterized the strategies of MGP analyses and the types and localizations of the identified mutations and showed that 13 and 11 of the analyzed genes were significantly associated with an increased BC and OC risk, respectively. The risk attributed to some of these genes (e.g., CDKN2A and PALB2 for BC) was similar to that observed for BRCA2. The analysis also showed a substantial difference in the profile of genes contributing to either BC or OC risk, including genes specifically associated with a high risk of OC but not BC (e.g., RAD51C, and RAD51D).
CONCLUSIONS: Our study provides strong statistical proof, defines the risk for many genes often considered candidates for BC/OC predisposition and excludes the role of other genes frequently analyzed in the MGPs. In the context of clinical diagnostics, the results support the knowledge-based interpretation of identified mutations.

Das S, Salami SS, Spratt DE, et al.
Bringing Prostate Cancer Germline Genetics into Clinical Practice.
J Urol. 2019; 202(2):223-230 [PubMed] Related Publications
PURPOSE: Until recently the role of germline genetics in prostate cancer care was not well defined. While important questions remain, we reviewed the current understanding of germline genetic alterations related to prostate cancer. We discuss the clinical implications for genetic counseling, genetic testing, early detection and treatment in men with these mutations.
MATERIALS AND METHODS: We searched PubMed® for English language articles published since 2001 with the key words "germline mutations," "BRCA," "family history" or "prostate cancer genetics." We also used relevant data from websites, including the Centers for Medicare and Medicaid Services, National Comprehensive Cancer Network®, Bureau of Labor Statistics and National Society of Genetic Counselors websites.
RESULTS: A number of germline mutations in DNA damage repair genes ( BRCA1, BRCA2, CHEK2, ATM and PALB2) and in DNA mismatch repair genes ( MLH1, MSH2, MSH6 and PMS2) can drive the development of prostate cancer. Careful genetic counseling coupled with multipanel gene testing can help identify men with these mutations and provide enhanced understanding of the disease risk. Cascade testing of family members can then have an impact extending well beyond the index patient. In men with a pathogenic germline mutation the optimal early detection paradigm is not well defined. Data from the IMPACT study ( ClinicalTrials.gov NCT00261456) that the cancer detection rate is substantially elevated in BRCA1 and BRCA2 carriers at prostate specific antigen greater than 3 ng/ml has helped establish the importance of close prostate specific antigen screening in these men. Additionally, BRCA2 and likely other DNA damage repair mutations are associated with aggressive disease, although it is not yet clear how this impacts localized disease management. However, there is strong evidence that patients with metastatic, castration resistant prostate cancer who have DNA damage repair defects respond positively to targeting PARP enzymes. In many cancers there is also evidence that patients with an increased tumor mutational burden, such as in Lynch syndrome, are particularly sensitive to immune checkpoint inhibitors.
CONCLUSIONS: Emerging evidence supports the implementation of germline genetic counseling and testing as a key component of prostate cancer management. Further research is needed to elucidate the clinical significance of lesser known germline mutations and develop optimal screening, early detection and treatment paradigms in this patient population.

Dąbrowski A, Ułaszewski S, Niedźwiecka K
Rapid and easy detection of the five most common mutations in BRCA1 and BRCA2 genes in the Polish population using CAPS and ACRS-PCR methods.
Acta Biochim Pol. 2019; 66(1):33-37 [PubMed] Related Publications
In this publication we present a fast method of diagnosing the most common polymorphisms of BRCA1 and BRCA2 genes in Poland - C61G [c.300T>G], C64R [c.190T>C], 4153delA [c.4035delA], 3819del5 [c.3700_3704delGTAAA], and C5972T [c.5744C>T]. Our procedure is based on the use of the cleaved amplified polymorphic sequences (CAPS) and artificially created restriction site (ACRS) PCR techniques. The precise selection of appropriate primer sequences and restriction enzymes enabled specific cuts of DNA fragments. The final quantity and size of the obtained products depend on the presence or the absence of the mutations. The obtained results are unambiguous and do not have to be confirmed by sequencing. The methods of detection of the C61G, C64R, 4153delA, 3819del5, and C5972T mutations in the BRCA1 and BRCA2 genes described by us do not require a sequencing process, which is more expensive, time-consuming and associated with numerous errors. The technique developed by us enables the use of simple electrophoresis for accurate detection of the presence or absence of a specific mutation. Our procedures are fast, precise and unambiguous.

Bick U, Engel C, Krug B, et al.
High-risk breast cancer surveillance with MRI: 10-year experience from the German consortium for hereditary breast and ovarian cancer.
Breast Cancer Res Treat. 2019; 175(1):217-228 [PubMed] Related Publications
PURPOSE: To report on 10 years of high-risk service screening with annual MRI in the German Consortium for Hereditary Breast and Ovarian Cancer (GC-HBOC).
METHODS: A cohort of 4,573 high-risk, previously unaffected women (954 BRCA1 carriers, 598 BRCA2 carriers, 3021 BRCA1/2 non-carriers) participating in the GC-HBOC surveillance program was prospectively followed. Screening outcomes for 14,142 screening rounds with MRI between 2006 and 2015 were analyzed and stratified by risk group, type of screening round, and age.
RESULTS: A total of 221 primary breast cancers (185 invasive, 36 in situ) were diagnosed within 12 months of an annual screening round with MRI. Of all cancers, 84.5% (174/206, 15 unknown) were stage 0 or I. In BRCA1 carriers, 16.9% (10/59, 5 unknown) of all incident cancers (screen-detected and interval cancers combined) and in BRCA2 carriers 12.5% (3/24, 4 unknown) were stage IIA or higher, compared to only 4.8% (2/42, 2 unknown) in high-risk BRCA1/2 non-carriers. Program sensitivity was 89.6% (95% CI 84.9-93.0) with no significant differences in sensitivity between risk groups or by age. Specificity was significantly lower in the first screening round (84.6%, 95% CI 83.6-85.7) than in subsequent screening rounds (91.1%, 95% CI 90.6-91.7), p < 0.001. Cancer detection rates (CDRs) and as a result positive predictive values were strongly dependent on type of screening round, risk group and patient age. CDRs ranged from 43.5‰ (95% CI 29.8-62.9) for the first screening round in BRCA2 carriers to 2.9‰ (95% CI 1.3-6.3) for subsequent screening rounds in high-risk non-carriers in the age group 30 to 39 years.
CONCLUSIONS: High-risk screening with MRI was successfully implemented in the GC-HBOC with high sensitivity and specificity. Risk prediction and inclusion criteria in high-risk non-carriers need to be adjusted to improve CDRs and thus screening efficacy in these patients.

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