Germline Mutations In CHEK2 Research Articles

Homologous recombination deficiency (HRD) score in germline BRCA2- versus ATM-altered prostate cancer.

The homologous recombination deficiency (HRD) score integrates three DNA-based measures of genomic instability, and has been understudied in prostate cancer. Given the recent FDA-approval of two PARP inhibitors for prostate cancer, HRD score analysis could help to refine treatment selection. We assessed HRD score (defined as the sum of loss-of-heterozygosity, telomeric allelic imbalance, and large-scale state transitions) in three cohorts of primary prostate cancer, including a Johns Hopkins University (JHU) cohort with germline mutations in BRCA2, ATM or CHEK2 (n=64), the TCGA cohort (n=391), and the PROGENE cohort (n=102). In the JHU cohort, tumors with germline BRCA2 mutations had higher HRD scores (median=27) than those with germline ATM or CHEK2 mutations (median=16.5 [p=0.029] and 9 [p<0.001], respectively). For TCGA tumors without underlying HR pathway mutations, the median HRD score was 11, significantly lower than ovarian carcinoma lacking BRCA1/2 mutations (median=28). In the absence of HR gene mutations, the median HRD score was unexpectedly higher among prostate cancers with TP53 mutations versus those without (17 vs 11; p=0.015); this finding was confirmed in the PROGENE cohort (24 vs 16; p=0.001). Finally, among eight BRCA2-altered patients who received olaparib, progression-free survival trended longer in those with HRD scores above versus below the median (14.9 vs 9.9 months). We conclude that HRD scores are low in primary prostate cancer and higher in cases with germline BRCA2 or somatic TP53 mutations. Germline BRCA2-altered cases have significantly higher HRD scores than germline ATM-altered or CHEK2-altered cases, consistent with the lower efficacy of PARP inhibitors among the latter.

CHEK2 Germline Variants in Cancer Predisposition: Stalemate Rather than Checkmate.

Germline alterations in many genes coding for proteins regulating DNA repair and DNA damage response (DDR) to DNA double-strand breaks (DDSB) have been recognized as pathogenic factors in hereditary cancer predisposition. The ATM-CHEK2-p53 axis has been documented as a backbone for DDR and hypothesized as a barrier against cancer initiation. However, although CHK2 kinase coded by the CHEK2 gene expedites the DDR signal, its function in activation of p53-dependent cell cycle arrest is dispensable. CHEK2 mutations rank among the most frequent germline alterations revealed by germline genetic testing for various hereditary cancer predispositions, but their interpretation is not trivial. From the perspective of interpretation of germline CHEK2 variants, we review the current knowledge related to the structure of the CHEK2 gene, the function of CHK2 kinase, and the clinical significance of CHEK2 germline mutations in patients with hereditary breast, prostate, kidney, thyroid, and colon cancers.

Germline Contributions to Clonal Hematopoiesis in Solid Cancer Patients

Clonal hematopoiesis (CH), defined by expansion of clones in the hematopoietic system, has been linked to internal (aging) and external (smoking and oncologic therapy) factors in patients with advanced solid tumors. The effects of inherited variants, however, have yielded inconclusive results in few studies so far. While comparison of CH prevalence between monozygotic and dizygotic pairs failed to detect genetic predisposition to CH, others have shown associations with germline variants near TERT and TET2, and a potential link between pathogenic CHEK2 germline variants and CH has been proposed. Here, utilizing prospective tumor-blood paired sequencing data from a large institutional clinical cohort, we link inherited pathogenic variants in cancer predisposition genes to CH and show interactions between germline and somatic mutations in DNA damage repair (DDR) genes. We analyzed sequencing data from 32,748 cancer patients who have undergone MSK-IMPACT testing using paired tumor and blood samples to study the associations between CH and rare pathogenic and likely-pathogenic (P/LP) germline variants. P/LP germline mutations were identified in the blood using an in-house developed random forest algorithm, trained using known P/LP mutations. Following joint anonymization of P/LP germline mutations and CH variants, linear regression models by gene were used to test for associations, accounting for known CH confounders. In our cohort, 9,697 patients (29.6%) harbored at least one CH mutation, while P/LP germline variants were detected in 1,793 of these CH patients. P/LP germline variants in CHEK2 (OR=1.29, p=4.49x10-2) were found to be significantly associated with CH in a pan-cancer analysis. Interestingly, germline P/LP and CH co-mutations in CHEK2 were very rare; we identified only one patient with CH and germline mutations in CHEK2 out of 161 patients with germline CHEK2 mutations, compared to 304 patients with CH CHEK2 mutation when CHEK2 is wild-type in the germline. In contrast, ATM and TP53 showed increased number of patients with co-mutations in P/LP germline and CH mutations in the same gene, with 14 out of 84 patients with germline mutations in ATM compared to 254 when not mutated (OR=7.05, p=2.08x10-7) , and 3 out of 16 compared to 387 for TP53 (OR=10.94, p=5.44x10-3). Further, we found mutual exclusivity between CHEK2 P/LP germline variants and CH mutations in PPM1D (OR=0.18, p=1.79x10-2). This relationship was replicated by comparing CHEK2 germline mutations and somatic PPM1D mutations in the solid tumor samples within the same cohort and same pattern of mutual exclusivity also persisted in comparisons of other DDR pathway genes (i.e. ATM vs PPM1D and TP53 vs PPM1D). When studying specific cancer types, a significant association between CHEK2 P/LP germline variants and CH in breast cancer patients was also identified (OR=2.33, p=2.64x10-3). Furthermore, trends between germline mutations in ATM and CH rates in breast cancer (OR=1.84, p=9.82x10-2) and lung adenocarcinoma (OR=2.22, p=8.91x10-2) patients were observed. Our results support the already reported link between rare pathogenic germline mutations in CHEK2 with CH in cancer patients, with stronger association among breast cancer patients (Comen E. et al, 2019). Moreover, this study suggests a close relationship between inherited variants and CH mutations within the DDR genes in solid tumor patients and points out to interesting mutual exclusivity patterns between these same genes. Intriguingly, hematopoietic stem cells have been largely related to proficient DDR systems in order to regulate HSC maintenance and tissue homeostasis in the hematopoietic system. All in all, associations identified in this study might translate into enhanced clinical surveillance for CH and associated comorbidities cancer patients harboring these germline mutations. Disclosures Bolton: GRAIL: Research Funding. Papaemmanuil:Novartis: Consultancy, Honoraria; Celgene: Consultancy, Honoraria, Research Funding; Illumina: Consultancy, Honoraria; Prime Oncology: Consultancy, Honoraria; Isabl: Current equity holder in private company, Membership on an entity's Board of Directors or advisory committees; Kyowa Hakko Kirin: Consultancy, Honoraria; MSKCC: Patents &amp; Royalties. Levine:Prelude Therapeutics: Research Funding; Qiagen: Current equity holder in publicly-traded company, Membership on an entity's Board of Directors or advisory committees; Janssen: Consultancy; Astellas: Consultancy; Morphosys: Consultancy; Novartis: Consultancy; Amgen: Honoraria; Gilead: Honoraria; Roche: Consultancy, Honoraria, Research Funding; Lilly: Consultancy, Honoraria; Celgene: Consultancy, Honoraria, Research Funding; C4 Therapeutics: Current equity holder in private company, Membership on an entity's Board of Directors or advisory committees; Loxo: Current equity holder in private company, Membership on an entity's Board of Directors or advisory committees; Isoplexis: Current equity holder in private company, Membership on an entity's Board of Directors or advisory committees; Imago: Current equity holder in private company, Membership on an entity's Board of Directors or advisory committees. Berger:Illumina: Research Funding; Grail: Research Funding; Roche: Consultancy. Zehir:Illumina: Honoraria; Memorial Sloan Kettering Cancer Center: Current Employment.

Alterations of DNA damage repair genes in Chinese colorectal cancer patients.

e16121 Background: Colorectal cancer (CRC) is the second most common cancer in women and third in men. DNA damage repair (DDR) deficiency has emerged as a predictive biomarker for chemotherapy, PARP and immune checkpoint inhibitors. However, comprehensive molecular characteristics of DDR variants in Chinese CRC patients is lacking. Methods: Formalin fixed, paraffin embedded (FFPE) tumor tissues and matched blood samples were collected for targeted next-generation sequencing (NGS) assay. The testing was carried out in a College of American Pathologists (CAP) accredited and Clinical Laboratory Improvement Amendments (CLIA) certified laboratory. Alterations of six functional gene sets involved in DDR pathways: homologous recombination (HR), mismatch repair (MMR), base excision repair (BER), nonhomologous end-joining (NHEJ), checkpoint factors (CPF) and Fanconi anemia (FA) were analyzed. The association of DDR gene mutations with TMB/MSI was assessed. Results: In total, 319 CRC patients were recruited, 127 female and 192 male with a median age of 59 (range 23-92). Over one third (36%,115/319) patients had at least one mutation in DDR genes. Mutation rates varied in different DDR pathway: HR (20.7%), CPF (15.1%), FA (11.3%), MMR (10.3%), BER (8.8%), and NHEJ (5.3%). The most frequently mutated DDR genes were ARID1A (13.4%), ATM (10.2%), BRCA2 (6.8%), MLH1 (5.6%), MSH6 (5.6%), POLE (5.0%). Germline mutations in MLH1 (2.5%), BRCA2 (1.2%), MSH2 (0.9%), MSH6 (0.9%), FANCA (0.9%), ATM (0.6%), BRCA1 (0.3%), and CHEK2 (0.3%) were detected in 24 patients. DDR variations were enriched in the right-side CRC compared to the left side CRC (50% vs. 32.8%, p= 0.024). Early stage (I-II) harbored more DDR variations. 20.1% of patients had high TMB (≥10 muts/Mb) with a median of 51 muts/Mb (10-326.7 mus/Mb). Patients with DDR mutations had a significantly higher TMB than patients with wild type DDR (8.5 vs. 4.6 muts/Mb, p&lt; 0.001). All CRC tumors with high MSI harbored DDR mutations. Importantly, the mutations in “HM” (HR/MMR), but not BER/CPF/NHEJ/FA mutations, were significantly correlated with high MSI ( p&lt; 0.001). Conclusions: DDR gene alterations occurred in 36% of Chinese CRC patients and were enriched in right sided tumors. DDR pathway alterations are relatively frequent in CRC and consideration for biomarker-enriched clinical trials with PARP, immune checkpoint inhibitors, and novel combinations are warranted.

Влияние герминальных мутаций в генах BRCA2 и CHEK2 на время до развития кастрационной резистентности у больных метастатическим гормоночувствительным раком предстательной железы

as shown in previous studies, mutations in the BRCA1/2 and CHEK2 genes are associated with worsened long-term results of the definitive treatment for localized prostate cancer (PCa). to evaluate the prognostic value of germline BRCA1/2 and CHEK2 mutations on time to castration-resistance in patients with metastatic PCa (mPCa), receiving hormonal therapy in the first-line systemic treatment. A total of 76 patients with mPCa receiving hormonal therapy with luteinizing hormone-releasing hormone analogue (LHRHa) in N.N. Blokhin National Medical Research Center of Oncology were recruited in our prospective study. All patients were genotyped for germline mutations in the BRCA1/2 and CHEK2 genes by real-time polymerase chain reaction using a set "OncoGenetics" (LLC "Research and Production Company DNA-Technology", Russia, registration certificate No 2010/08415) and the Sanger sequencing using a set "Beckman Coulter enomeLab GeXP". In addition, a histologic grade and volume of metastatic disease were evaluated. Pathogenic and possibly pathogenic mutations in the BRCA2 and CHEK2 gene were identified in 19 (25%) patients. No cases of BRCA1 mutations were detected. Median time to castration resistance was significantly lower in BRCA2 and CHEK2 mutation carriers (7.93 mo, 95% confidence interval (CI) 2.62-13.25), than in non-carriers (48,66 mo, 95% CI 31.05-68.26, p<0,001). Cox analysis confirmed three independent unfavorable prognostic factors. The results of our study and other publications have confirmed limited efficacy of standard approach to treatment hormone-sensitive mPCa in germline mutation BRCA2 and CHEK2 carriers. However, the main objective of studies was to assess the survival rates in these patients at the stage of castration-resistant mPCa. Our results demonstrated that germline BRCA2 and CHEK2 mutations are independent unfavorable predictors in patients with mPCa which are associated with decreased time to castration resistance (HR 3.04, 95% CI 1.63-5.66, p<0.001), particularly in subgroup with low volume metastatic disease (HR 4.59, 95% CI 2.06-10.22, p<0,001). An evaluation of a prognostic value of mutations in other DNA repair genes requires additional research.

Coexisting Germline CHEK2 and Somatic BRAFV600E Mutations in Papillary Thyroid Cancer and Their Association with Clinicopathological Features and Disease Course.

BRAFV600E is the most common somatic mutation in papillary thyroid carcinoma (PTC) and the majority of evidence indicates that it is associated with an aggressive clinical course. Germline mutations of the CHEK2 gene impair the DNA damage repair process and increase the risk of PTC. Coexistence of both mutations is expected to be associated with poorer clinical course. We evaluated the prevalence of concomitant CHEK2 and BRAFV600E mutations and their associations with clinicopathological features, treatment response, and disease course in PTC patients. The study included 427 unselected PTC patients (377 women and 50 men) from one center. Relationships among clinicopathological features, mutation status, treatment response, and disease outcomes were assessed. Mean follow-up was 10 years. CHEK2 mutations were detected in 15.2% and BRAFV600E mutations in 64.2% patients. Neither mutation was present in 31.4% cases and both BRAFV600E and CHEK2 mutations coexisted in 10.8% patients. No significant differences in clinicopathological features, initial risk, treatment response, or disease outcome were detected among these patient groups. CHEK2 mutations were significantly associated with older age, while BRAFV600E was significantly associated with older age and extrathyroidal extension. The coexistence of both mutations was not associated with more aggressive clinicopathological features of PTC, poorer treatment response, or disease outcome.

Выявление BRCA- и CHEK2-ассоциированных форм рака молочной железы и рака яичников у женщин в амбулаторной клинической практике врача-онколога

Introduction. Currently breast cancer is considered a heterogeneous disease and spectrum of several biological subtypes. Ovarian cancer is also characterized by a variety of molecular genetic alterations. Both diseases remain the leading specific causes of death in age group 40-49 and 50-59 for females. Objective: to evaluate the frequency of mutations in the genes BRCA1/2 and CHEK2 in patients with breast cancer and patients with ovarian cancer, as well as in women with benign neoplasms of the mammary glands, and to analyze their clinical and morphological correlations with the disease characteristics in the routine clinical practice of an outpatient oncologist. Patients and Methods: Seventy-six women were included in the present analysis. All of them were observed by the oncologist in Consultative and diagnostic center of Burdenko Main Military Clinical Hospital (Moscow) between January 2016 and May 2019, and were divided in three groups: patients with breast cancer (n=20), patients with ovarian cancer (n=17) and control group of women with benign neoplasms of the mammary glands (fibrocystic mastopathy in 29, breast fibroadenoma in 11), with no history of any oncological disease. One patient has metachronous malignant neoplasms of independent (primary) multiple sites: breast and ovarian cancer. All women were genotyped for pathogenic germline mutations 185delAG, 300T&gt;C (Cyse61Gly), 2080delA, 3819delGTAAA, 3875delGTCT, 4153delA, 5382InsC in the gene BRCA1, mutation 6174delT in the gene BRCA2 and mutations IVS2+1G&gt;A, I157T and IVS2+1G&gt;A in the gene CHEK2 by polymerase chain reaction real-time using a set “OncoGenetics” (LLC «Research and Production Company DNA-Technology», Russia, registration certificate № 2010/08415). Results: Pathogenic germline BRCA1 mutations were identified in 4 (20%) patients with breast cancer, 3 (17,6%) patients with ovarian cancer and 1 (2,5%) women with breast fibroadenoma. Pathogenic germline CHEK2 mutations were identified in 3 (15%) patients with breast cancer, all cases were represented by the I157T mutation. In the control group carriers of BRCA1 or BRCA2 mutations (n=2) were associated with early onset development of breast fibroadenoma in the age before 30 years. The risk of BRCA or CHEK2 mutated genes was significant higher in patients with breast cancer (45%, HR 9.0, 95% CI: 2.14 - 37.8) compared with the control group of women with benign breast tumors (5%, p &lt;0.001). The risk of BRCA or CHEK2 mutations was also higher in patients with ovarian cancer (17.6%, HR 3.53, 95% CI: 0.65 – 19.26) compared with the control group (5%), but the difference did not reach significance (p=0.151). Genotyping BRCA and CHEK2 results were correlated (r = 0.423) with a family history: mutations were more often detected in women with a family history of cancer (42.9% versus 7.3%, p = 0.001). Women with identified mutations showed an increased risk of early onset cancer development before the age of 50 years (69.2%, HR 4.33, 95% CI: 1.64 - 11.36, p = 0.003) compared with wild-type carriers BRCA and CHEK2 genes (16%). The only case of primary multiple metachronous malignant tumors of the breast and ovaries, as well as cases of bilateral breast cancer lesions were detected only among carriers of BRCA1/2 mutations. The prevalence of aggressive high grade cancer was higher in patients with BRCA and CHEK2 mutations (63.6%, HR 2.45, 95% CI: 0.87 - 6.90) than in patients with wild type genes (47.1 %), however, the difference did not reach significance (p = 0.141). Conclusions: Our results have shown the relevance and value of identifying for BRCA- and CHEK2-related breast cancer and ovarian cancer in women in everyday clinical practice. The vast majority of cases of breast and ovarian cancer among carriers of BRCA1/2 and CHEK2 mutations are found in the working and reproductive age of women and are associated with unfavorable disease characteristics - high grade and lower survival.

DNA damage repair (DDR) gene alterations as a predictive biomarker for response to platinum-containing chemotherapy in advanced biliary tract cancer (BTC).

4078 Background: Although many studies using whole-exome sequencing or targeted sequencing have reported the molecular profile of BTC, its clinical implications remains unclear. In this study, we assessed a predictive role of DDR gene mutations in advanced BTC patients treated with platinum-containing regimen. Methods: Eighty-eight patients with pathologically-confirmed BTC who received first-line gemcitabine-cisplatin combination (n = 69) or fluoropyrimidine-oxaliplatin combination (n = 19) were included in this analysis. Targeted exome sequencing was performed using Foundation Medicine T7 assay or in-house OncoPanel AMC. Germline or somatic mutations in ATM, ATR, BAP1, BARD1, BRCA1, BRCA2, BRIP1, CHEK2, FAM175A, GEN1, MLH1, MSH2, MSH6, MRE11A, NBN, PALB2, PMS2, RAD50, RAD51, RAD51C, RAD51D, and XRCC2 were classified as DDR gene mutations. Data regarding baseline characteristics and treatment outcomes were retrospectively obtained from medical records. Results: The median age was 62 years (range, 25-78), with male comprising 64.8% (n = 57). By primary tumor site, 21 patients with GBC (23.9%), 44 with ICC (50.0%) and 23 with ECC (26.1%) were included. Most patients received palliative chemotherapy for their initially metastatic (50.0%) or recurred (44.3%) disease; the rest 5.7% had locally advanced disease. The median PFS and OS of overall patients were 7.1 and 16.1 months, respectively with median follow-up duration of 20.2 months. DDR gene mutations were found in 63.5% of patients. BRCA2 (18.2%) was most frequently mutated, followed by ATM (13.6%), and ATR (8.0%). DDR gene mutations were significantly associated with prolonged PFS (presence vs. absence; median, 6.9 vs. 5.7 months; P = 0.013) and OS (median, 21.0 vs. 13.3 months, P = 0.009). The impact of DDR gene mutations remained significant in multivariate analyses for PFS that included other prognostic factors (hazard ratio, 0.51; P = 0.009), but not for OS. Conclusions: The presence of DDR gene mutations might be a promising predictive biomarker for response to platinum-based chemotherapies in advanced BTC. Future investigation using novel agents targeting DDR gene alteration in BTC are warranted.

Impact of germline DNA-repair gene BRCA2 and CHEK2 mutations on time to castration resistance in patients with metastatic hormone-naïve prostate cancer: A single center analysis.

5056 Background: Germline mutations in DNA repair genes are common in patients with andvanced and metastatic prostate cancer (mPCa). Although BRCA mutation carriers have worse outcomes than noncarriers when conventionally treated for local or locally advanced PCa, recent studies reported conflicting results regarding their aggressiveness in patients with advanced disease. This study aimed to examine the impact of germline BRCA1/2 and CHEK2 mutations on time to castration-resistance in patients with mPCa, receiving hormonal androgen deprivation therapy (ADT). Methods: A total of 76 patients with hormone-naive mPCa treated with first line ADT by luteinizing hormone-releasing hormone analogue (LHRHa) between 2014 and 2017 were recruited. Median follow-up was 34,8 mo. We focused on age, volume of metastatic spread, histologic grade, family history. All patients were genotyped for germline mutations in the BRCA1, BRCA2 and CHEK2 genes by polymerase chain reaction real-time and the Sanger sequencing. We used the standard definition of castration-resistance PCa (CRPC). Median time to CRPC were estimated using the Kaplan-Meier method, generated curves were compared using the log-rank test. Cox regression analyses were used to assess the prognostic value of BRCA1/2 and CHEK2 mutations. Results: Pathogenic and likely pathogenic germline mutations in the BRCA2 and CHEK2 gene were identified in 19 (25 %) patients. No cases of BRCA1 mutations were detected. Median time to CRPC was significantly shorter in BRCA2 and CHEK2 mutation carriers (7.9 mo, 95 % confidence interval (CI) 2.6 – 13.3), than in non-carriers (48.7 mo, 95 % CI 31.1 – 68.3, p &lt; 0,001). There was no significant difference in median time to CRPC in BRCA2 (7.9 mo, 95 % CI 0.0 - 16.3) and CHEK2 mutation carriers (6.1 mo, 95 CI 5.0 - 7.2, p = 0,448) meanwhile both were shorter than in non-carriers (p = 0.002 and &lt; 0,001). Multivariate analysis confirmed both BRCA2 (hazard ratio [HR]: 2.63; 95 CI 1.32-5.26, p = 0.006) and CHEK2 (HR 6.66, 95 CI 2.35-18.89, p &lt; 0.001) mutations as an independent prognostic factor for time to CRPC, particularly in mPCa with low-volume metastatis spread (HR 3.09, 95 % CI 1.36–7.05, р = 0.007 and HR 14.1, 95 % CI 3.65-54.4, p &lt; 0.001). Conclusions: BRCA2 and CHEK2 carriers had worse outcomes (shortened time to CRPC) than noncarriers when conventionally treated for metastatic PCa by standard first-line hormone treatment with LHRHa.

Impact of germline CHEK2 mutations on biochemical relapse free survival and metastasis free survival after radical treatment for patients with prostate cancer

Objective : to evaluate the prognostic value of pathogenic germline BRCA1, BRCA2 and CHEK2 mutations on biochemical relapse-free survival (BRFS) and metastasis-free survival (MFS) following radical treatment in patients with localized and locally advanced prostate cancer (PCa). Materials and methods . Tumor features and outcomes of 102 patients with PCa were analyzed. In all patients nadir prostate-specific antigen (PSA) have been achieved: radical prostatectomy was undergone by 85 patients; 17 patients received radical radiotherapy. Exclusion criteria were postoperative nadir PSA &gt;0.2 ng/mL, adjuvant hormone therapy. During follow-up a total of 65 (63.7 %) patients developed biochemical relapse (BCR), and 39 (38.2 %) patients developed metastatic progression of PCa. All patients were genotyped for clinically significant pathogenic germline mutations 1100delC, I157Tand IVS2+1G&gt;A in the CHEK2gene, 185delAG, 4153delA, 5382insC, 3875del4, 3819del5, C61G, 2080delA in the BRCA1 gene, 6174delT in the BRCA2 gene by polymerase chain reaction real-time using a set “OncoGenetics” (LLC “Research and Production Company DNA-Technology”, Russia, registration certificate № 2010/08415). The second step was the determination of the coding part of the BRCA1 and BRCA2 genes by the Sanger sequencing using a set “Beckman Coulter enomeLab GeXP”. Results . Pathogenic germline mutations in the CHEK2 gene were identified in 16 (15.7 %) patients: heterozygous missense mutation I157T (c.470T&gt;C, rs17879961) was identified in 15 (14.7 %) patients, heterozygous mutation IVS2+1G&gt;A (c.319+1G&gt;A, rs765080766) was identified in 1 (0.9 %) patient. No cases of the 1100delC mutation in the CHEK2 gene and clinically significant mutations in the BRCA1 and BRCA2 genes were detected. Germline mutations I157TandIVS2+1G&gt;A in the CHEK2gene are statistically significant independent unfavorable prognostic factor for BRFS (hazard ratio (HR) 3.272; 95 % confidence interval (CI) 1.688—6.341, p &lt;0.001) and marginally significant independent unfavorable prognostic factor for MFS (HR 2.186; 95 % CI 0.932—5.126, p = 0.072). Subgroup analysis confirm independent prognostic value of germline CHEK2 mutations in patients with localized PCa (for BRFS HR 3.048; 95 % CI 1.024—9.078; p = 0.045; for MFS HR 5.168; 95 % CI 1.231—21.699; p = 0,025), and its marginally significant prognostic value in patient with locally advanced PCa T3-T4N0M0 (for BRFS HR 3.099; 95 % CI 0.991-9.689; р = 0.052) and TanyN1M0 stage (for MFS HR 5.089; 95 % CI 0.724-35.755; p = 0.102). Germline mutations I157T and IVS2+1G&gt;A in the CHEK2 gene are associated with increased risk of early BCR during 12 months (HR 3.795; 95 % CI 2.06-6.98; p &lt;0.001) and early metastatic progression during 24 months (HR 6.72; 95 % CI 2.02-22.34; p = 0.004) following radical treatment. This study has certain limitations due to its retrospective recruitment and a small sample of patients. Conclusions . Our results confirm that germline CHEK2 mutations I157T and IVS2+1G&gt;A are an unfavorable prognostic factor for patients with PCa, associated with increased risk of early biochemical relapse and metastatic progression, worse BRFS and MFS.

Risk-adapted approach to prostate cancer screening

Mass prostatic specific antigen (PSA) testing (population-based PSA screening) has remained controversial, nevertheless there are men cohorts likely to benefit from PSA screening. Heritable factors contribute to 60 % risk for developing familial prostate cancer. Despite the fact that its clinical application is challenging due to polygenic inheritance, advances in new generation sequencing technologies permit identifying highly penetrant germline mutations in genes BRCA1, BRCA2, CHEK2, HOXB13 and MMR associated with tremendous increase in risk of developing the prostate cancer. Several germline mutations are associated with clinically aggressiveness of disease and shortened survival. Targeted screening that is based on family history and genomic aberrations should be the next step towards the precision medicine. Men at elevated risk should been performed for early detection are those with familiar history of prostate cancer, or BRCA1, BRCA2, CHEK2, HOXB13 and MMR pathogenic germline mutation carriers, or first line relatives diagnosed with certain types of cancer. Systematic PSA testing in 1–2 years among germline mutation carriers men beginning at age 45 years would contribute to increase in early detection of localized prostate cancer resulting in more chance of curative treatment and improve survival rates

Characterization and prevalence of two novel CHEK2 large deletions in Greek breast cancer patients.

Germline CHEK2 mutations confer increased cancer risk, for breast and other types, which is variable depending on the specific mutation. Of these, Large Genomic Rearrangements (LGRs) have been rarely reported; to date only eight LGRs have been published with just the Czech founder mutation, the deletion of exons 9 and 10, being molecularly characterized and studied extensively. The present study aimed to molecularly define and determine the contribution of two rare, apparently novel CHEK2 LGRs, among Greek breast cancer patients. These specifically involve a ~6 kb in-frame deletion of exons 2 & 3 that removes CHEK2's FHA domain and a ~7.5 kb in-frame deletion of exon 6, which removes an α-helix of CHEK2's kinase domain. The latter was identified in 5 out of 2355 (0.22%) patients tested, while haplotype analysis revealed a common disease-associated haplotype, suggesting a single common ancestor and a Greek founder. Although in-frame, this LGR is predicted to be damaging by a yeast-based functional assay and structure-function predictions. The present study highlights the existence of rare, population-specific, genomic events in a known breast cancer predisposing gene, which can explain a proportion of hereditary breast cancer. Identification of such mutation carriers is rather important since appropriate clinical actionability will be inferred.

Mutational analysis of candidate genes in Israeli male breast cancer cases.

To define the mutational spectrum of several candidate gene mutations in Israeli male breast cancer cases. MBC cases counselled at the Oncogenetics unit, Sheba Medical Center from January 1998 to June 2017 were included. Relevant clinical and oncological data and cancer phenotype were retrieved. All participants were genotyped for the predominant Jewish BRCA1 and BRCA2 germline mutations using a chip-based assay. Those who tested negative were further genotyped for three recurring mutations in CHEK2 (c.1100delC, p.S428F, p.I157T), and single mutations in the FANCM (c.5791C>T), and RAD51D (c.556C>T) genes, by direct sequencing. The ethics committee approved the study. Overall, 61 MBC were identified and genotyped, 41 (67.2%) were Ashkenazim, age at diagnosis was 58.1 ± 12.6years, and 31 (50.8%) had a family history of cancer. Of genotyped individuals, one (1.6%) harboured the 185delAG* BRCA1 mutation, 7 (11.4%) the 6174delT*BRCA2 mutation and 2 (3.2%) other recurring mutations in BRCA2 (overall 10/61-16.4% BRCA1/BRCA2 mutation carriers). Of BRCA-negative cases, 3/51 (5.9%) carried the p.S428F *CHEK2 mutation. None was a carrier of the other genotyped mutations in CHEK2, FANCM or RAD51D. BRCA1, BRCA2 and CHEK2 germline mutations contribute to inherited predisposition to MBC in Israel.

A comprehensive evaluation of CHEK2 germline mutations in men with prostate cancer.

Germline mutations in CHEK2 have been associated with prostate cancer (PCa) risk. Our objective is to examine whether germline pathogenic CHEK2 mutations can differentiate risk of lethal from indolent PCa. A case-case study of 703 lethal PCa patients and 1455 patients with low-risk localized PCa of European, African, and Chinese origin was performed. Germline DNA samples from these patients were sequenced for CHEK2. Mutation carrier rates and their association with lethal PCa were analyzed using the Fisher exact test and Kaplan-Meier survival analysis. In the entire study population, 40 (1.85%) patients were identified as carrying one of 15 different germline CHEK2 pathogenic or likely pathogenic mutations. CHEK2 mutations were detected in 16 (2.28%) of 703 lethal PCa patients compared with 24 (1.65%) of 1455 low-risk PCa patients (P = 0.31). No association was found between CHEK2 mutation status and early-diagnosis or PCa-specific survival time. However, the most common mutation in CHEK2, c.1100delC (p.T367 fs), had a significantly higher carrier rate (1.28%) in lethal PCa patients than low-risk PCa patients of European American origin (0.16%), P = 0.0038. The estimated Odds Ratio of this mutation for lethal PCa was 7.86. The carrier rate in lethal PCa was also significantly higher than that (0.46%) in 32 461 non-Finnish European subjects from the Exome Aggregation Consortium (ExAC) (P = 0.01). While overall CHEK2 mutations were not significantly more common in men with lethal compared to low-risk PCa, the specific CHEK2 mutation, c.1100delC, appears to contribute to an increased risk of lethal PCa in European American men.

Abstract P4-06-03: Characteristics of CHEK2 mutation carriers in a large academic health center in Michigan

Abstract Background: Germline mutations in CHEK2, a cell-cycle checkpoint kinase, are associated with increased susceptibility to breast, colon, and other cancers. The clinical characteristics and cancer risks of patients with CHEK2 mutations is under investigation. Methods: Patients identified with a pathogenic germline CHEK2 mutation between September 2013 and April 2017 were evaluated. Clinical multigene panel testing using next generation sequencing technologies was utilized. All patients received comprehensive pre- and post-test genetic counseling. Genetic testing results, demographics, tumor characteristics and outcomes were analyzed. Results: A total of 107 CHEK2 mutation carriers were identified, of whom 88 (82%) were females. The vast majority were Caucasian (99%), and of those, 17 (16%) had Ashkenazi Jewish ancestry. The median age at time of genetic testing was 52 (range: 22-89). The most common mutations identified were: I157T (28%), c.1100delC (27%), p.S428F (15%) and c.1427C&amp;gt;T (9%). Seven of these patients (7%) were found to carry a second pathogenic cancer risk mutation: BRCA, ATM, NBN, NF1, and MUTYH. One patient was found to carry 3 pathogenic mutations (1100delC, ATM, and BRCA). Sixty-three (59%) patients had a prior diagnosis of malignancy, with a mean age of diagnosis of 53. Of the 88 females, the most common type of malignancy was breast cancer (55%), with a mean age of diagnosis of 52 (range: 35-79). Of the 19 males, breast cancer was seen in 4 patients. The most common known histopathology was invasive ductal carcinoma (72%), followed by DCIS (15%), invasive lobular carcinoma (9%), and papillary carcinoma (4%). Majority of the patients had breast tumors with low or moderate grade (62%), less than two centimeters (61%), node negative (70%), and estrogen/progesterone receptor positive/HER2neu negative (96%). Two patients had triple negative breast cancers. Of the 48 female mutation carriers with breast cancer, 38% underwent bilateral mastectomy. The 1- and 5-year survival was 100% with a median follow up of 57 months. Five of the 48 females developed a contralateral breast cancer, with a median time to contralateral recurrence of 6 years (range: 3-17). Two patients developed in-breast tumor recurrence at 9 and 19 years, respectively. Other cancers observed were papillary thyroid cancer (3 patients), melanoma (2 patients), and prostate (2 patients). One patient developed angiosarcoma of the chest wall two years after radiation therapy. Conclusion: Our study describes the unique clinical characteristics of CHEK2 mutation carriers in a US-based clinic at Beaumont Health. Majority of breast cancers were early stage, hormone receptor positive and demonstrated excellent outcomes. Despite the early stage, a significant proportion of patients underwent bilateral mastectomy. Additional pathogenic mutations were identified in 10% of patients; validating the importance of panel testing in assessing cancer risk. Future studies are needed to better define the clinical presentation, cancer risks, mutational spectrum, and outcomes of CHEK2 mutation carriers in order to provide tailored screening and management guidelines for this emerging population. Citation Format: Blankenship LM, Yadav S, Yumpo Cardenas P, Zakalik D. Characteristics of CHEK2 mutation carriers in a large academic health center in Michigan [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P4-06-03.

Abstract P3-04-02: Molecular analysis of breast cancers from individuals with hereditary cancer syndromes secondary to mutations in BRCA1, BRCA2, ATM, CHEK2, and PALB2

Abstract Background: Despite a growing understanding of the somatic landscape of breast tumors from BRCA1 and BRCA2 mutation carriers, less is known about breast tumors from carriers of germline mutations in other homologous recombination and DNA repair pathway genes such as ATM, CHEK2, and PALB2. Methods: We identified 44 clinically annotated breast cancer cases that included carriers of germline mutations in BRCA1 (n=9), BRCA2 (n=9), ATM (n=5), CHEK2 (n=7), and PALB2 (n=6) from the Hereditary Cancer Risk Program at BUMC. Sporadic breast cancers cases (n=8) were also collected. Genomic DNA and RNA were extracted from macro-dissected FFPE tumor sections, adjacent normal FFPE tissue, along with constitutional genomic DNA from blood. Expanded whole exome sequencing (WES) was performed on normal/tumor pairs and RNA-seq from tumors for each case. Bioinformatics analysis was performed using industry standard methods for somatic characterization. Results: All germline mutations were confirmed by WES. Somatic mutational analysis and copy number profiling from WES revealed the greatest similarities among BRCA1 and CHEK2 carriers. As expected, TP53 mutations were found in 8 of 9 BRCA1 carriers as all were triple negative subtype. We also detected somatic TP53 mutations in tumors from 4 of 7 CHEK2 carriers. Somatic TP53 mutations were found in only 1 of 7 BRCA2 tumors and 1 of 4 PALB2 tumors tested. Furthermore, BRCA1 and CHEK2 tumors showed trends of having higher mutation burden. Analysis of copy number BRCAness demonstrated stronger similarities between BRCA1, ATM, CHEK2, and PALB2 tumors. BRCA2 tumors were unique with fewer events and characterized by specific amplifications including 11q23 (CCND1) and 17q23 (BRIP1). Hierarchical clustering of RNA-seq data revealed strong clustering of BRCA1 tumors compared to all other tumors, predominantly attributed to breast cancer subtype. Furthermore, pathway analysis of genes that distinguish BRCA1 mutation positive versus non-BRCA mutated tumors showed strong correlation to pro-inflammatory and immune pathway signatures. Conclusions: Molecular analysis of 44 breast cancers from individuals with inherited predisposition to breast cancer via BRCA1, BRCA2, ATM, CHEK2, and PALB2 germline mutations demonstrated strongest somatic similarities between BRCA1 and CHEK2 tumors although all BRCA1 were TNBC and all CHEK2 tumors were ER positive. Marked differential gene expression differences in RNA expression patterns were observed in BRCA1 mutation carriers compared with all other groups analyzed. Our study is among the first to interrogate the profile of non-BRCA mutated hereditary breast cancers. Citation Format: Blum JL, Wong S, Pearson EJ, Nair A, Snipes GJ, Briones N, Baker A, Cropp CD, Carpten JD. Molecular analysis of breast cancers from individuals with hereditary cancer syndromes secondary to mutations in BRCA1, BRCA2, ATM, CHEK2, and PALB2 [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P3-04-02.

CHEK2 Germ Line Mutations are Lacking among Familial and Sporadic Breast Cancer Patients in Rwanda

Worldwide, breast cancer is the most frequent neoplasm and the second leading cause of cancer death among females. It dominates in both developed and developing countries and represents a major public health problem. The etiology is multifactorial and involves exogenous agents as well as endogenous factors. Although they account for only a small fraction of the breast cancer burden, mutations in the BRCA1 and BRCA2 genes are known to confer a high risk predisposition. Mutations in moderate/low-penetrance genes may also contribute to breast cancer risk. Previous studies have shown that mutations in the CHEK2 gene are involved in breast cancer susceptibility due to its impact on DNA repair processes and replication checkpoints. This study was conducted to evaluate the frequencies of three germline mutations in CHEK2 gene (c.1100delC, R145W and I157T) in breast cancers in Rwanda. Using direct DNA sequencing, we analyzed 41 breast cancer patients and 42 normal breast controls but could not detect any positives. CHEK2 mutations may be a rare event in Rwandan population and may only play a minor if an role in breast cancer predisposition among familial and sporadic cases.

Pathologic findings in breast, fallopian tube, and ovary specimens in non-BRCA hereditary breast and/or ovarian cancer syndromes: a study of 18 patients with deleterious germline mutations in RAD51C, BARD1, BRIP1, PALB2, MUTYH, or CHEK2

Germline BRCA mutations account for a significant proportion of genetic/familial risk of breast and ovarian cancer (GBOC) susceptibility, but a broader spectrum of GBOC susceptibility genes has emerged in recent years. Genotype-to-phenotype correlations are known for some established forms of GBOC; however, whether such correlations exist for less common GBOC variants is unclear. We reviewed our institution's experience with non-BRCA GBOC, looking specifically for trends in pathologic and clinical features. Eighteen women with deleterious germline mutations in RAD51C (5 patients), BARD1 (1 patient), BRIP1 (2 patients), PALB2 (3 patients), MUTYH (2 patients), or CHEK2 (5 patients) were identified between January 2011 and December 2016. Thirteen (72%) of 18 patients developed carcinoma of the breast, fallopian tube, or ovary, with 1 patient developing 2 separate primary neoplasms. Twelve (86%) of 14 tumors occurred in the breast. One (7%) arose in the fallopian tube and another (7%) arose in the ovary. Evidence of genotype-phenotype correlation was not identified. However, some data suggest that the type of alteration in select genes may influence tumor behavior and patient outcome. In our PALB2 mutation cohort, 2 patients with frameshift mutations led to early onset and rapid progression to stage IV breast cancer in contrast to stage IA breast cancer in 1 patient with a nonsense mutation. Despite no apparent genotype-phenotype trends, our data indicate that some loss-of-function variants in PALB2 may lead to differences in tumor behavior and patient outcome.

Enrichment of germline DNA-repair gene mutations in patients with colorectal cancer.

1500 Background: Twin studies showed that 30% of all colorectal cancer (CRC) patients have an inherited genetic susceptibility. Several CRC predisposition genes have been described to date. However, mutations in these genes explain the risk in only 5-10% of CRC cases. In this study, we hypothesized that some of the CRC heritability may be explained by excess disruptive germline mutations in DNA repair genes (DRGs). Methods: Exome sequencing data of 716 in the discovery cohort (CanSeq and NHS/HPFS studies) and 1609 CRC patients in the validation cohort (TCGA and NSCCG studies) were used to evaluate germline variants in a pre-selected group of 42 DRGs and 12 known CRC risk genes. Frequencies of disruptive mutations in our cohorts were examined relative to 27173 non-Finnish European cancer-free adults from the ExAC cohort to evaluate for enrichment. Results: Of 716 patients in the discovery cohort, 27 (3.8%) patients harbored germline mutations in APC (n = 11), MSH6 (n = 2), MUTYH (n = 11), CHEK2 (n = 1) and TP53 (n = 2). Interestingly, germline mutations in ATM and PALB2 were significantly enriched in our CRC discovery cohort (OR = 2.7; P = 0.044; and OR = 4.8; P = 0.026, respectively). Evaluation of germline data from another 1609 CRC patients (validation cohort) also showed significantly higher rates of ATM mutations (5; 0.7%; OR = 2.1; P = 0.044), and a trend for enrichment of PALB2 mutations (3; 0.4%; OR = 2.8; P = 0.056). Secondary analysis of actionable germline mutations in a highly penetrant cancer risk gene set ( ATM, BRCA1, BRCA2, BRIP1 and PALB2) suggest a broader enrichment trend in CRC patients for these genes (Discovery: OR = 1.7; P = 0.06; Validation: OR = 2; P = 1.96e-04). Conclusions: Our analysis of germline variants in 2325 CRC patients showed the first robust evidence for germline ATM mutations to confer a higher risk of developing CRC. We also presented evidence to support PALB2 as a potential novel CRC risk gene. Overall, our study shows that mutations in some DRGs may explain some of the missing CRC heritability. It also indicates that a significant percentage of CRC patients, who carry mutations in highly actionable genes where cancer screening recommendations for patients and families do exist, are not captured with current testing recommendations.

CHEK2 MUTATIONS INCREASE RISK FOR PROSTATE CANCER BUT DO NOT DIFFERENTIATE RISK OF LETHAL FROM INDOLENT DISEASE

You have accessJournal of UrologyProstate Cancer: Advanced (including Drug Therapy) II1 Apr 2017CHEK2 MUTATIONS INCREASE RISK FOR PROSTATE CANCER BUT DO NOT DIFFERENTIATE RISK OF LETHAL FROM INDOLENT DISEASE S. Lilly Zheng, Rong Na, Misop Han, Kristian Novakovic, Kathleen Wiley, Sarah Isaacs, Alan Partin, Michael McGuire, Patrick Walsh, Charles Brendler, Brian Helfand, William Isaacs, and Jianfeng Xu S. Lilly ZhengS. Lilly Zheng More articles by this author , Rong NaRong Na More articles by this author , Misop HanMisop Han More articles by this author , Kristian NovakovicKristian Novakovic More articles by this author , Kathleen WileyKathleen Wiley More articles by this author , Sarah IsaacsSarah Isaacs More articles by this author , Alan PartinAlan Partin More articles by this author , Michael McGuireMichael McGuire More articles by this author , Patrick WalshPatrick Walsh More articles by this author , Charles BrendlerCharles Brendler More articles by this author , Brian HelfandBrian Helfand More articles by this author , William IsaacsWilliam Isaacs More articles by this author , and Jianfeng XuJianfeng Xu More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2017.02.1573AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES A recent study published in the New England Journal of Medicine found that CHEK2 germline pathogenic mutations are associated with metastatic prostate cancer (PCa) risk. The objective of this study is to assess whether CHEK2 germline mutations differentiate risk of lethal from indolent PCa. METHODS A retrospective case-case study of 261 patients who died of PCa and 352 patients with localized PCa of European American descent was conducted. Germline DNA from each of the 613 subjects was sequenced for DNA repair genes and cancer-related genes through whole exome sequencing (WES) or targeted sequencing. Mutations were annotated according to the American College of Medical Genetics guidelines. RESULTS Among the 613 PCa patients in the study, 11 (1.79%) carried CHEK2 germline pathogenic mutations, which was significantly higher than the estimate from the general population (ExAC database: 0.61%, P<0.0001). However, the mutation carrier rate in lethal PCa patients (5/261=1.92%) was not significantly higher than either the localized cases in our study (6/352=1.70%, P=1.00) or in The Cancer Genome Atlas (2/406=0.49%, P=0.12). Among lethal cases, CHEK2 mutation carriers and non-carriers had similar mean age of death (77.0 and 73.0 years, respectively, P=0.72) and mean time to death (10.0 and 8.0 years, respectively, P=0.96). In the survival analysis of the entire study, CHEK2 mutations did not predict PCa-specific survival (Figure, log-rank P=0.86, comparing with non-carriers). In contrast, germline mutations of BRCA1/2 and ATM predicted worse PCa specific survival (all log-rank P<0.05, comparing with CHEK2 carriers and non-carriers). CONCLUSIONS CHEK2 germline mutations increase risk for PCa, but do not differentiate risk of lethal from indolent disease or PCa-specific survival. © 2017FiguresReferencesRelatedDetails Volume 197Issue 4SApril 2017Page: e678 Advertisement Copyright & Permissions© 2017MetricsAuthor Information S. Lilly Zheng More articles by this author Rong Na More articles by this author Misop Han More articles by this author Kristian Novakovic More articles by this author Kathleen Wiley More articles by this author Sarah Isaacs More articles by this author Alan Partin More articles by this author Michael McGuire More articles by this author Patrick Walsh More articles by this author Charles Brendler More articles by this author Brian Helfand More articles by this author William Isaacs More articles by this author Jianfeng Xu More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...