Mohammad Reza Akbari

Breast cancer etiology involves a complex interplay of various risk factors, with genetic alterations playing a significant role in susceptibility to the disease. While mutations in genes such as BRCA1 and BRCA2 are well established in elevating breast cancer risk, their potential role in predicting metastatic progression remains unclear. A recent study by Mei et al. suggested that a common germline variant in the PCSK9 gene (rs562556) may increase metastasis risk and lower survival rates in breast cancer patients. To investigate this association, we evaluated the relationship between the PCSK9 rs562556 variant genotypes and survival outcomes in two cohorts: patients with BRCA1 mutations and those with familial breast cancer lacking mutations in known susceptibility genes. Our study included 1052 BRCA1 mutation carriers, 467 familial breast cancer patients of unknown genetic etiology, and 1404 controls. Genotyping was performed using TaqMan genotyping and whole-exome sequencing. Survival analyses were conducted using Kaplan-Meier survival curves and Cox proportional hazards models. We found no significant association between PCSK9 rs562556 variant and breast cancer mortality or time to death following distant recurrence in either cohort. This finding does not support PCSK9 prognostic impact in breast cancer that may be modified by additional genetic or environmental factors.

Purpose: ATRIP (ATR-interacting protein) is a critical partner of ATR (ataxia telangiectasia and Rad3-related). The ATR-ATRIP heterodimer plays an essential role in initiating homologous recombination repair (HRR) during replication stress and inducing double-stranded DNA breaks following unresolved stalled replication forks. Our team recently identified ATRIP as a novel breast cancer susceptibility gene candidate through whole-exome sequencing (WES) of familial breast cancer patients and healthy controls from the Polish founder population, with subsequent validation in both Polish and British cohorts. In the present study, we report for the first time the detection of a novel deleterious mutation in ATRIP among several members of an Iranian family with clustering of breast cancer who were negative for mutations in the already known breast cancer risk genes. Methods: Six family members underwent germline DNA testing by WES, following initial negative results from multigene panel testing. Candidate variants were confirmed by Sanger sequencing and assessed according to ACMG guidelines. Results: We detected a novel ATRIP frameshift mutation (NM_130384.3:c.1033delC) in four of six family members that were tested, including two individuals affected with breast cancer. No pathogenic variants were found in other known cancer susceptibility genes. Conclusions: This is the first report of a deleterious ATRIP mutation in an Iranian family with familial breast cancer, suggesting a potential role of ATRIP in hereditary breast cancer. Further studies are required to confirm the role of ATRIP in breast cancer susceptibility, refine risk assessment, and evaluate potential personalized therapeutic strategies. In the interim, genetic counseling for ATRIP mutation carriers should proceed with caution, given current limitations in clinical interpretation.

Background: Carriers of a pathogenic variant (PV) in BRCA1 face a high risk of breast cancer. This study estimated the risk of developing breast cancer according to mutation type and location. Methods: BRCA1 carriers with no personal history of breast cancer or bilateral mastectomy were included. Detailed information on clinical and family history was collected by questionnaire. Survival analysis was used to estimate 15-year cumulative risk according to PV type and location. Results: A total of 3677 BRCA1 carriers were followed for a mean of 7.2 years (range 0.1–15.0 years); 481 incident breast cancers were documented. Overall, the 15-year cumulative incidence was 25%. Risk estimates varied by exon, ranging from 9% (exon 21) to 19% (exon 12) to 36% (exon 15); however, strata were small. Carriers of four founder mutations common in Eastern Europe (c.5263_5264insC, c.181T > G, c.66_67delAG and c.4034delA) experienced a lower-than-expected cancer risk (15.9–24.4%) compared to other PVs (28.8%) (p = 0.02). Conclusions: Although our data suggests some variability in penetrance based on specific BRCA1 PV, this was based on a large number of founder mutations. Breast cancer management strategies should continue to be based on comprehensive risk assessment.

PURPOSE: Although prostate cancer is generally associated with favorable outcomes, metastatic disease remains incurable. Additionally, a subset of individuals with high-risk or metastatic disease are likely to harbor at least one germline variant in known prostate cancer association genes. Because of differences in cohort selection and sequencing strategies, the prevalence of germline variants in global populations is unclear. METHODS: A whole-exome sequencing (WES) approach was used to explore germline variants in a cohort of patients with metastatic prostate cancer from India. In total, 276 individuals treated at the All India Institute of Medical Sciences in New Delhi, India, were prospectively and consecutively recruited. Blood specimens underwent standard WES and bioinformatic analysis to determine the prevalence of pathogenic and likely pathogenic (PV/LPV) prostate cancer variants, which were then assessed for associations with clinical features. RESULTS: In total, PV/LPVs were detected in 11% of individuals across eight genes linked to prostate cancer, most frequently in BRCA2 (3.98%). The distribution reflects previously published findings from other global cohorts, although frequencies in the prevalence of specific variants differ slightly. No relationship between variant status and clinical features were detected, although analysis of a larger cohort may show otherwise. CONCLUSION: These results indicate that germline screening for prostate cancer following existing guidelines yield similar variant detection frequencies when focusing on individuals with metastatic disease in the Indian context. In summary, some men are more likely to develop an advanced form of metastatic prostate cancer than others because of differences in their genes, known as variants. This study looked at the how many of these variants are in a group of patients from India. We found that the number of variants in this group was similar to those from other parts of the world, including more found in a gene called BRCA2 .

GEN1 is implicated in DNA damage repair, as are several other breast cancer susceptibility genes, and is included in several comprehensive next-generation sequencing (NGS) testing panels. To investigate the possible association of GEN1 variants with breast cancer risk, we sequenced this gene in 617 Polish women with hereditary breast cancer (HBC) and 300 Polish cancer-free controls. No protein-truncating variants were detected in the conserved part of GEN1 (first 480 codons). Two frameshift variants were detected in the last exon of GEN1: c.2515_2519delAAGTT (p.Lys839Glufs*2) and c.1929_1932delAAAG (p.Lys645Cysfs*29). The p.Lys839Glufs*2 variant was detected in 21.1% of 617 HBC cases and 18.4% of 300 controls (p = 0.38). The p.Lys645Cysfs*29 variant was rare, seen in 0.6% of 617 HBC cases and 0.3% of 300 controls. The variant was then detected in 38 (0.24%) of 15,930 unselected breast cancer cases and 8 (0.17%) of 4702 cancer-free female controls from Poland (OR = 1.40, p = 0.49). Clinical characteristics of breast tumors in the 38 carriers of p.Lys645Cysfs*29 and 15,892 non-carriers were similar. Survival was similar among variant carriers and non-carriers (the age-adjusted HR = 0.87, p = 0.76). The wild-type GEN1 allele was retained in all five breast cancers of carriers of p.Lys645Cysfs*29. No cancer type was more frequent in the relatives of 35 p.Lys645Cysfs*29 variant carriers compared to the relatives of 14,592 non-carriers. We conclude that GEN1 is unlikely to be a high or moderate-risk breast cancer susceptibility gene. Our study has clinical implications for genetic counseling and suggests that GEN1 changes should be reclassified as variants of uncertain significance (VUS) when they are detected in clinical testing panels.

Introduction In Canada, care for individuals with hereditary cancer is fragmented across the provinces and territories, with carriers of pathogenic variants in cancer-susceptibility genes seeing multiple doctors and often advocating for their own management plans. The need for a national registry of carriers has been well established. While other cancer consortia exist, barriers in clinical and genomic data sharing limit the utility of the information gathered. Methods and analysis Within the province of Ontario, the Ontario Hereditary Cancer Research Network (OHCRN), funded by and located at the Ontario Institute for Cancer Research, is being developed to fill this gap. The registry will hold clinical, genomic and self-reported data from consented carriers and will make this data available to qualified researchers in anonymised and aggregated form. Individuals must agree to certain components to participate in OHCRN; there are also optional consents participants can agree to without impacting their involvement in OHCRN. We plan to open the registry for participant enrolment in mid-2025. Ethics and dissemination Ethics approval for registry creation was obtained from the Ontario Cancer Research Ethics Board, a centralised body that streamlines reviews for cancer research studies in Ontario. Registry data will be disseminated to participants and researchers as aggregate data through the OHCRN website and presented at scientific conferences, made available to Ontario Health (Cancer Care Ontario) to inform policy and evidence-based practice, as well as be available to the scientific community for further analysis and answering relevant questions.

Coronary artery disease (CAD), the most prevalent cardiovascular disease, is the leading cause of death worldwide. Heritable factors play a significant role in the pathogenesis of CAD. It has been proposed that approximately one-third of patients with CAD have a positive family history, and individuals with such history are at similar to 1.5-fold increased risk of CAD in their lifespans. Accordingly, the long-recognized familial clustering of CAD is a strong risk factor for this disease. Our study aimed to identify candidate genetic variants contributing to CAD by studying a cohort of 60 large Iranian families with at least two members in different generations afflicted with premature CAD (PCAD), defined as established disease at <= 45 years in men and <= 55 years in women. Exome sequencing was performed for a subset of the affected individuals, followed by prioritization and Sanger sequencing of candidate variants in all available family members. Subsequently, apparently healthy carriers of potential risk variants underwent coronary computed tomography angiography (CCTA), followed by co-segregation analysis of the combined data. Putative causal variants were identified in seven genes, ABCG8, CD36, CYP27A1, PIK3C2G, RASSF9, RYR2, and ZFYVE21, co-segregating with familial PCAD in seven unrelated families. Among these, PIK3C2G, RASSF9, and ZFYVE21 are novel candidate CAD susceptibility genes. Our findings indicate that rare variants in genes identified in this study are involved in CAD development.

Esophageal squamous cell carcinoma (ESCC) has a very high incidence rate in northeastern Iran. Our team previously reported the BReast CAncer gene 2 (BRCA2) p.K3326* mutation as a moderately penetrant ESCC susceptibility variant in northern Iran (odds ratio (OR) = 3.64, 95% confidence interval (CI) = 1.74–7.59, P = 0.0003). Recently, it has been reported that aldehydes can induce BRCA2 haploinsufficiency in cells with a heterozygous pathogenic BRCA2 mutation and predispose them to carcinogenic effects. Based on this observation, we speculate that dysfunctional variants in Aldehyde Dehydrogenase 2 Family Member (ALDH2) may result in aldehyde-induced BRCA2 haploinsufficiency and increase cancer risk in BRCA2 mutation carriers. In support of this hypothesis, our team recently reported the breast cancer risk modifying effect of an ALDH2 common polymorphism, rs10744777, among Polish carriers of the BRCA2 p.K3326* mutation. In the current case-control study, we aimed to investigate the ESCC risk modifying effect of this ALDH2 polymorphism among BRCA2 p.K3326* mutation carriers. We assessed the interaction between the ALDH2 rs10744777 polymorphism and BRCA2 p.K3326* mutation in ESCC risk by genotyping this ALDH2 variant in the germline DNA of 746 ESCC cases and 1,373 controls from northern Iran who were previously genotyped for the BRCA2 p.K3326* mutation. Among a total of 464 individuals with TT genotype of the ALDH2 rs10744777 polymorphism, which is associated with lower ALDH2 expression, we found 9 of 164 cases versus 3 of 300 controls who carried the BRCA2 p.K3326* variant (OR = 5.66, 95% CI = 1.22–26.2, P = 0.018). This finding supports our hypothesis that the ALDH2-rs10744777 TT genotype may be a significant risk modifier of ESCC in individuals with a BRCA2 p.K3326* mutation.

Ovarian cancer has a high case fatality rate, but patients who have no visible residual disease after surgery have a relatively good prognosis. The presence of any cancer cells left in the peritoneal cavity after treatment may precipitate a cancer recurrence. In many cases, these cells are occult and are not visible to the surgeon. Analysis of circulating tumour DNA in the blood (ctDNA) may offer a sensitive method to predict the presence of occult (non-visible) residual disease after surgery and may help predict disease recurrence. We assessed 48 women diagnosed with serous ovarian cancer (47 high-grade and 1 low-grade) for visible residual disease and for ctDNA. Plasma, formalin-fixed paraffin-embedded (FFPE) tumour tissue and white blood cells were used to extract circulating free DNA (cfDNA), tumour DNA and germline DNA, respectively. We sequenced DNA samples for 59 breast and ovarian cancer driver genes. The plasma sample was collected after surgery and before initiating chemotherapy. We compared survival in women with no residual disease, with and without a positive plasma ctDNA test. We found tumour-specific variants (TSVs) in cancer cells from 47 patients, and these variants were sought in ctDNA in their post-surgery plasma. Fifteen (31.9%) of the 47 patients had visible residual disease; of these, all 15 had detectable ctDNA. Thirty-one patients (65.9%) had no visible residual disease; of these, 24 (77.4%) patients had detectable ctDNA. Of the patients with no visible residual disease, those patients with detectable ctDNA had higher mortality (20 of 27 died) than those without detectable ctDNA (3 of 7 died) (HR 2.32; 95% CI: 0.67–8.05), although this difference was not statistically significant (p = 0.18). ctDNA in post-surgical serum samples may predict the presence of microscopic residual disease and may be a predictor of recurrence among women with ovarian cancer. Larger studies are necessary to validate these findings.