Gene and pathway level analyses of germline DNA-repair gene variants and prostate cancer susceptibility using the iCOGS-genotyping array

Germline Sequencing Analysis to Inform Clinical Gene Panel Testing for Aggressive Prostate Cancer

Importance

Germline gene panel testing is recommended for men with advanced prostate cancer (PCa) or a family history of cancer. While evidence is limited for some genes currently included in panel testing, gene panels are also likely to be incomplete and missing genes that influence PCa risk and aggressive disease.

Objective

To identify genes associated with aggressive PCa.

Design, Setting, and Participants

A 2-stage exome sequencing case-only genetic association study was conducted including men of European ancestry from 18 international studies. Data analysis was performed from January 2021 to March 2023. Participants were 9185 men with aggressive PCa (including 6033 who died of PCa and 2397 with confirmed metastasis) and 8361 men with nonaggressive PCa.

Exposure

Sequencing data were evaluated exome-wide and in a focused investigation of 29 DNA repair pathway and cancer susceptibility genes, many of which are included on gene panels.

Main Outcomes and Measures

The primary study outcomes were aggressive (category T4 or both T3 and Gleason score ≥8 tumors, metastatic PCa, or PCa death) vs nonaggressive PCa (category T1 or T2 and Gleason score ≤6 tumors without known recurrence), and metastatic vs nonaggressive PCa.

Results

A total of 17 546 men of European ancestry were included in the analyses; mean (SD) age at diagnosis was 65.1 (9.2) years in patients with aggressive PCa and 63.7 (8.0) years in those with nonaggressive disease. The strongest evidence of association with aggressive or metastatic PCa was noted for rare deleterious variants in known PCa risk genes BRCA2 and ATM (P ≤ 1.9 × 10-6), followed by NBN (P = 1.7 × 10-4). This study found nominal evidence (P < .05) of association with rare deleterious variants in MSH2, XRCC2, and MRE11A. Five other genes had evidence of greater risk (OR≥2) but carrier frequency differences between aggressive and nonaggressive PCa were not statistically significant: TP53, RAD51D, BARD1, GEN1, and SLX4. Deleterious variants in these 11 candidate genes were carried by 2.3% of patients with nonaggressive, 5.6% with aggressive, and 7.0% with metastatic PCa.

Conclusions and Relevance

The findings of this study provide further support for DNA repair and cancer susceptibility genes to better inform disease management in men with PCa and for extending testing to men with nonaggressive disease, as men carrying deleterious alleles in these genes are likely to develop more advanced disease.

Genome-wide association study (GWAS) of circulating vitamin D outcomes among individuals of African ancestry

BACKGROUND

Vitamin D deficiency is more common among African-ancestry individuals and may be associated with adverse health outcomes. Vitamin D binding protein (VDBP) regulates concentrations of biologically active vitamin D.

OBJECTIVE

We conducted genome-wide association study (GWAS) of VDBP and 25-hydroxyvitamin D among African-ancestry individuals.

METHODS

Data were collected from 2,602 African American adults from the Southern Community Cohort Study (SCCS) and 6,934 African- or Caribbean-ancestry adults from the UK Biobank. Serum VDBP concentrations were available only in the SCCS and were measured by using the Polyclonal Human VDBP ELISA kit. Serum 25-hydroxyvitamin D concentrations for both study samples were measured by using Diasorin Liason, a chemiluminescent immunoassay. Participants were genotyped for single nucleotide polymorphisms (SNPs) with genome-wide coverage by using Illumina or Affymetrix platforms. Fine-mapping analysis was performed by using forward stepwise linear regression models including all variants with P value < 5 × 10-8 and within 250 kbps of a lead SNP.

RESULTS

We identified 4 loci notably associated with VDBP concentrations in the SCCS population: rs7041 (per allele β = 0.61 μg/mL, SE = 0.05, P = 1.4 × 10-48) and rs842998 (per allele β = 0.39 μg/mL, SE = 0.03, P = 4.0 × 10-31) in GC, rs8427873 (per allele β = 0.31 μg/mL, SE = 0.04, P = 3.0 × 10-14) near GC and rs11731496 (per allele β = 0.21 μg/mL, SE = 0.03, P = 3.6 × 10-11) in between GC and NPFFR2. In conditional analyses, which included the above-mentioned SNPs, only rs7041 remained notable (P = 4.1 × 10-21). SNP rs4588 in GC was the only GWAS-identified SNP associated with 25-hydroxyvitamin D concentration. Among UK Biobank participants: per allele β = -0.11 μg/mL, SE = 0.01, P = 1.5 × 10-13; in the SCCS: per allele β = -0.12 μg/mL, SE = 0.06, P = 2.8 × 10-02). rs7041 and rs4588 are functional SNPs that influence the binding affinity of VDBP to 25-hydroxyvitamin D.

CONCLUSIONS

Our results were in line with previous studies conducted in European-ancestry populations, showing that GC, the gene that directly encodes for VDBP, would be important for VDBP and 25-hydroxyvitamin D concentrations. The current study extends our knowledge of the genetics of vitamin D in diverse populations.

Patient-Level DNA Damage Repair Pathway Profiles and Anti-Tumor Immunity for Gastric Cancer

DNA damage repair (DDR) comprises the detection and correction of alterations in the chemical structure of DNA. The dysfunction of the DDR process has been determined to have important implications for tumor carcinogenesis, malignancy progression, treatment resistance, and prognosis assessment. However, the role of the DDR process in gastric cancer (GC) remains to be fully understood. Thus, a total of 2,019 GC samples from our hospital (Harbin Medical University Cancer Hospital in china) and 12 public data sets were included in our study. In this study, single-sample gene set enrichment analysis (ssGSEA) was used to generate the DDR pathway activity profiles of 8 DDR sub-pathways and identify a DDR pathway signature by combining the DDR sub-pathway gene sets. The DDR pathway profiling’s impacts on the clinical outcomes, biological functions, genetic variants, immune heterogeneity, and treatment responses were analyzed through multidimensional genomics and clinical data. The results demonstrate that the DDR pathway profiling was clearly distinguished between tumor and normal tissues. The DDR pathway profiling reveals patient-level variations, which may contribute to explaining the high heterogeneity of human GC for the biological features and treatment outcomes. Thus, tumors with low DDR signature scores were independently correlated with shorter overall survival time and significantly associated with mesenchymal, invasion, and metastasis phenotypes. The statistical model integrating this DDR pathway signature with other clinical predictors outperforms each predictor alone for predicting overall survival in discrimination, calibration, and net clinical benefit. Moreover, low DDR signature scores were tightly associated with genome stability, characterized by low tumor mutational burden (TMB) and low fractions of genome alteration. Furthermore, this study confirms that patients with low DDR pathway signature scores might not benefit from adjuvant chemotherapy and a monoclonal antibody directed against programmed cell death-1 ligand 1 (anti-PD1) therapy. These findings highlighted that the DDR pathway profiling confers important implications for patients with GC and provides insights into the specific clinical and molecular features underlying the DDR process, which may help to facilitate clinical management.

Genetic Factors of Non-Obstructive Azoospermia: Consequences on Patients' and Offspring Health

Non-Obstructive Azoospermia (NOA) affects about 1% of men in the general population and is characterized by clinical heterogeneity implying the involvement of several different acquired and genetic factors. NOA men are at higher risk to be carriers of known genetic anomalies such as karyotype abnormalities and Y-chromosome microdeletions in respect to oligo-normozoospermic men. In recent years, a growing number of novel monogenic causes have been identified through Whole Exome Sequencing (WES). Genetic testing is useful for diagnostic and pre-TESE prognostic purposes as well as for its potential relevance for general health. Several epidemiological observations show a link between azoospermia and higher morbidity and mortality rate, suggesting a common etiology for NOA and some chronic diseases, including cancer. Since on average 50% of NOA patients has a positive TESE outcome, the identification of genetic factors in NOA patients has relevance also to the offspring's health. Although still debated, the observed increased risk of certain neurodevelopmental disorders, as well as impaired cardiometabolic and reproductive health profile in children conceived with ICSI from NOA fathers may indicate the involvement of transmissible genetic factors. This review provides an update on the reproductive and general health consequences of known genetic factors causing NOA, including offspring's health.

Germline Sequencing DNA Repair Genes in 5545 Men With Aggressive and Nonaggressive Prostate Cancer

BACKGROUND

There is an urgent need to identify factors specifically associated with aggressive prostate cancer (PCa) risk. We investigated whether rare pathogenic, likely pathogenic, or deleterious (P/LP/D) germline variants in DNA repair genes are associated with aggressive PCa risk in a case-case study of aggressive vs nonaggressive disease.

METHODS

Participants were 5545 European-ancestry men, including 2775 nonaggressive and 2770 aggressive PCa cases, which included 467 metastatic cases (16.9%). Samples were assembled from 12 international studies and germline sequenced together. Rare (minor allele frequency < 0.01) P/LP/D variants were analyzed for 155 DNA repair genes. We compared single variant, gene-based, and DNA repair pathway-based burdens by disease aggressiveness. All statistical tests are 2-sided.

RESULTS

BRCA2 and PALB2 had the most statistically significant gene-based associations, with 2.5% of aggressive and 0.8% of nonaggressive cases carrying P/LP/D BRCA2 alleles (odds ratio [OR] = 3.19, 95% confidence interval [CI] = 1.94 to 5.25, P = 8.58 × 10-7) and 0.65% of aggressive and 0.11% of nonaggressive cases carrying P/LP/D PALB2 alleles (OR = 6.31, 95% CI = 1.83 to 21.68, P = 4.79 × 10-4). ATM had a nominal association, with 1.6% of aggressive and 0.8% of nonaggressive cases carrying P/LP/D ATM alleles (OR = 1.88, 95% CI = 1.10 to 3.22, P = .02). In aggregate, P/LP/D alleles within 24 literature-curated candidate PCa DNA repair genes were more common in aggressive than nonaggressive cases (carrier frequencies = 14.2% vs 10.6%, respectively; P = 5.56 × 10-5). However, this difference was non-statistically significant (P = .18) on excluding BRCA2, PALB2, and ATM. Among these 24 genes, P/LP/D carriers had a 1.06-year younger diagnosis age (95% CI = -1.65 to 0.48, P = 3.71 × 10-4).

CONCLUSIONS

Risk conveyed by DNA repair genes is largely driven by rare P/LP/D alleles within BRCA2, PALB2, and ATM. These findings support the importance of these genes in both screening and disease management considerations.

Active monitoring, radical prostatectomy and radical radiotherapy in PSA-detected clinically localised prostate cancer: the ProtecT three-arm RCT

BACKGROUND

Prostate cancer is the most common cancer among men in the UK. Prostate-specific antigen testing followed by biopsy leads to overdetection, overtreatment as well as undertreatment of the disease. Evidence of treatment effectiveness has lacked because of the paucity of randomised controlled trials comparing conventional treatments.

OBJECTIVES

To evaluate the effectiveness of conventional treatments for localised prostate cancer (active monitoring, radical prostatectomy and radical radiotherapy) in men aged 50-69 years.

DESIGN

A prospective, multicentre prostate-specific antigen testing programme followed by a randomised trial of treatment, with a comprehensive cohort follow-up.

SETTING

Prostate-specific antigen testing in primary care and treatment in nine urology departments in the UK.

PARTICIPANTS

Between 2001 and 2009, 228,966 men aged 50-69 years received an invitation to attend an appointment for information about the Prostate testing for cancer and Treatment (ProtecT) study and a prostate-specific antigen test; 82,429 men were tested, 2664 were diagnosed with localised prostate cancer, 1643 agreed to randomisation to active monitoring (n = 545), radical prostatectomy (n = 553) or radical radiotherapy (n = 545) and 997 chose a treatment.

INTERVENTIONS

The interventions were active monitoring, radical prostatectomy and radical radiotherapy.

TRIAL PRIMARY OUTCOME MEASURE

Definite or probable disease-specific mortality at the 10-year median follow-up in randomised participants.

SECONDARY OUTCOME MEASURES

Overall mortality, metastases, disease progression, treatment complications, resource utilisation and patient-reported outcomes.

RESULTS

There were no statistically significant differences between the groups for 17 prostate cancer-specific (p = 0.48) and 169 all-cause (p = 0.87) deaths. Eight men died of prostate cancer in the active monitoring group (1.5 per 1000 person-years, 95% confidence interval 0.7 to 3.0); five died of prostate cancer in the radical prostatectomy group (0.9 per 1000 person-years, 95% confidence interval 0.4 to 2.2 per 1000 person years) and four died of prostate cancer in the radical radiotherapy group (0.7 per 1000 person-years, 95% confidence interval 0.3 to 2.0 per 1000 person years). More men developed metastases in the active monitoring group than in the radical prostatectomy and radical radiotherapy groups: active monitoring, n = 33 (6.3 per 1000 person-years, 95% confidence interval 4.5 to 8.8); radical prostatectomy, n = 13 (2.4 per 1000 person-years, 95% confidence interval 1.4 to 4.2 per 1000 person years); and radical radiotherapy, n = 16 (3.0 per 1000 person-years, 95% confidence interval 1.9 to 4.9 per 1000 person-years; p = 0.004). There were higher rates of disease progression in the active monitoring group than in the radical prostatectomy and radical radiotherapy groups: active monitoring (n = 112; 22.9 per 1000 person-years, 95% confidence interval 19.0 to 27.5 per 1000 person years); radical prostatectomy (n = 46; 8.9 per 1000 person-years, 95% confidence interval 6.7 to 11.9 per 1000 person-years); and radical radiotherapy (n = 46; 9.0 per 1000 person-years, 95% confidence interval 6.7 to 12.0 per 1000 person years; p < 0.001). Radical prostatectomy had the greatest impact on sexual function/urinary continence and remained worse than radical radiotherapy and active monitoring. Radical radiotherapy's impact on sexual function was greatest at 6 months, but recovered somewhat in the majority of participants. Sexual and urinary function gradually declined in the active monitoring group. Bowel function was worse with radical radiotherapy at 6 months, but it recovered with the exception of bloody stools. Urinary voiding and nocturia worsened in the radical radiotherapy group at 6 months but recovered. Condition-specific quality-of-life effects mirrored functional changes. No differences in anxiety/depression or generic or cancer-related quality of life were found. At the National Institute for Health and Care Excellence threshold of £20,000 per quality-adjusted life-year, the probabilities that each arm was the most cost-effective option were 58% (radical radiotherapy), 32% (active monitoring) and 10% (radical prostatectomy).

LIMITATIONS

A single prostate-specific antigen test and transrectal ultrasound biopsies were used. There were very few non-white men in the trial. The majority of men had low- and intermediate-risk disease. Longer follow-up is needed.

CONCLUSIONS

At a median follow-up point of 10 years, prostate cancer-specific mortality was low, irrespective of the assigned treatment. Radical prostatectomy and radical radiotherapy reduced disease progression and metastases, but with side effects. Further work is needed to follow up participants at a median of 15 years.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN20141297.

FUNDING

This project was funded by the National Institute for Health Research Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 24, No. 37. See the National Institute for Health Research Journals Library website for further project information.

Clinical outcomes associated with pathogenic genomic instability mutations in prostate cancer: a retrospective analysis of US pharmacy and medical claims data

Background: Prostate cancer (PC) is a clinically heterogenous disease, and genetic mutations may be useful for patient risk stratification. This retrospective cohort study compared clinical outcomes, pharmacy use, and outpatient resource use in PC patients with and without pathogenic genomic instability mutations, including DNA repair deficiency (DRD) mutations and those in TP53, PTEN, and RB1. Methods: Patients ≥18 years newly-diagnosed with PC between June 2011-March 2016 were identified in medical and prescription claims databases linked to a genomic dataset. All-cause and PC-specific pharmacy use and outpatient resource use (office visits, laboratory tests, radiology examinations, and radiation therapies) over 1, 2, and 3 years and time to evidence of disease progression after PC diagnosis, based on secondary cancer diagnosis codes and treatments received, were evaluated in mutation carriers with ≥1 of 24 gene mutations and in a sub-set of DRD gene mutation carriers, with each compared to non-mutation carriers. Results: Mutation carriers (n = 274) and non-mutation carriers (n = 74) had similar demographic and clinical features. Non-mutation carriers had lower risks of developing metastasis and castration-resistant PC than mutation carriers (hazard ratio [HR] = 0.7, 95% CI = 0.5-0.9; HR = 0.5, 95% CI = 0.3-0.9, respectively) and DRD mutation carriers (HR = 0.5, 95% CI = 0.3-0.7; HR = 0.4, 95% CI = 0.2-0.7, respectively). Compared to non-mutation carriers, mutation carriers had more all-cause pharmacy claims over 2 years of follow-up (74.4 vs 59.1, p = 0.04) and more PC-specific pharmacy claims over 2 years (11.1 vs 6.5, p = 0.01) and 3 years (17.9 vs 9.8, p = 0.01) of follow-up. No differences were observed in outpatient resource use during the follow-up period by mutation status. Conclusion: PC patients carrying ≥1 pathogenic DNA instability mutation, and DRD mutation carriers specifically, had higher clinical burden than non-mutation carriers. Targeted therapies for these patients are needed to reduce clinical burden and associated healthcare resource utilization.

A novel RNA aptamer identifies plasma membrane ATP synthase beta subunit as an early marker and therapeutic target in aggressive cancer

PURPOSE

Primary breast and prostate cancers can be cured, but metastatic disease cannot. Identifying cell factors that predict metastatic potential could guide both prognosis and treatment.

METHODS

We used Cell-SELEX to screen an RNA aptamer library for differential binding to prostate cancer cell lines with high vs. low metastatic potential. Mass spectroscopy, immunoblot, and immunohistochemistry were used to identify and validate aptamer targets. Aptamer properties were tested in vitro, in xenograft models, and in clinical biopsies. Gene expression datasets were queried for target associations in cancer.

RESULTS

We identified a novel aptamer (Apt63) that binds to the beta subunit of F1Fo ATP synthase (ATP5B), present on the plasma membrane of certain normal and cancer cells. Apt63 bound to plasma membranes of multiple aggressive breast and prostate cell lines, but not to normal breast and prostate epithelial cells, and weakly or not at all to non-metastasizing cancer cells; binding led to rapid cell death. A single intravenous injection of Apt63 induced rapid, tumor cell-selective binding and cytotoxicity in MDA-MB-231 xenograft tumors, associated with endonuclease G nuclear translocation and DNA fragmentation. Apt63 was not toxic to non-transformed epithelial cells in vitro or adjacent normal tissue in vivo. In breast cancer tissue arrays, plasma membrane staining with Apt63 correlated with tumor stage (p < 0.0001, n = 416) and was independent of other cancer markers. Across multiple datasets, ATP5B expression was significantly increased relative to normal tissue, and negatively correlated with metastasis-free (p = 0.0063, 0.00039, respectively) and overall (p = 0.050, 0.0198) survival.

CONCLUSION

Ecto-ATP5B binding by Apt63 may disrupt an essential survival mechanism in a subset of tumors with high metastatic potential, and defines a novel category of cancers with potential vulnerability to ATP5B-targeted therapy. Apt63 is a unique tool for elucidating the function of surface ATP synthase, and potentially for predicting and treating metastatic breast and prostate cancer.

DNA Damage Response in Prostate Cancer

Prostatic adenocarcinoma (PCa) remains a significant health concern. Although localized PCa can be effectively treated, disseminated disease remains uniformly fatal. PCa is reliant on androgen receptor (AR); as such, first-line therapy for metastatic PCa entails suppression of AR signaling. Although initially effective, recurrent tumors reactivate AR function, leading to a lethal stage of disease termed castration-resistant PCa (CRPC). Recent findings implicate AR signaling in control of DNA repair and show that alterations in DNA damage repair pathways are strongly associated with disease progression and poor outcome. This review will address the DNA repair alterations observed in the clinical setting, explore the anticipated molecular and cellular consequence of DNA repair dysfunction, and consider clinical strategies for targeting tumors with altered DNA repair.

Genetic intersection of male infertility and cancer

Recent epidemiological studies have identified an association between male factor infertility and increased cancer risk, however, the underlying etiology for the shared risk has not been investigated. It is likely that much of the association between the two disease states can be attributed to underlying genetic lesions. In this article we review the reported associations between cancer and spermatogenic defects, and through database searches we identify candidate genes and gene classes that could explain some of the observed shared genetic risk. We discuss the importance of fully characterizing the genetic basis for the relationship between cancer and male factor infertility and propose future studies to that end.

Stepwise approach to SNP-set analysis illustrated with the Metabochip and colorectal cancer in Japanese Americans of the Multiethnic Cohort

BACKGROUND

Common variants have explained less than the amount of heritability expected for complex diseases, which has led to interest in less-common variants and more powerful approaches to the analysis of whole-genome scans. Because of low frequency (low statistical power), less-common variants are best analyzed using SNP-set methods such as gene-set or pathway-based analyses. However, there is as yet no clear consensus regarding how to focus in on potential risk variants following set-based analyses. We used a stepwise, telescoping approach to analyze common- and rare-variant data from the Illumina Metabochip array to assess genomic association with colorectal cancer (CRC) in the Japanese sub-population of the Multiethnic Cohort (676 cases, 7180 controls). We started with pathway analysis of SNPs that are in genes and pathways having known mechanistic roles in colorectal cancer, then focused on genes within the pathways that evidenced association with CRC, and finally assessed individual SNPs within the genes that evidenced association. Pathway SNPs downloaded from the dbSNP database were cross-matched with Metabochip SNPs and analyzed using the logistic kernel machine regression approach (logistic SNP-set kernel-machine association test, or sequence kernel association test; SKAT) and related methods.

RESULTS

The TGF-β and WNT pathways were associated with all CRC, and the WNT pathway was associated with colon cancer. Individual genes demonstrating the strongest associations were TGFBR2 in the TGF-β pathway and SMAD7 (which is involved in both the TGF-β and WNT pathways). As partial validation of our approach, a known CRC risk variant in SMAD7 (in both the TGF-β and WNT pathways: rs11874392) was associated with CRC risk in our data. We also detected two novel candidate CRC risk variants (rs13075948 and rs17025857) in TGFBR2, a gene known to be associated with CRC risk.

CONCLUSIONS

A stepwise, telescoping approach identified some potentially novel risk variants associated with colorectal cancer, so it may be a useful method for following up on results of set-based SNP analyses. Further work is required to assess the statistical characteristics of the approach, and additional applications should aid in better clarifying its utility.

Next generation mapping reveals novel large genomic rearrangements in prostate cancer

Complex genomic rearrangements are common molecular events driving prostate carcinogenesis. Clinical significance, however, has yet to be fully elucidated. Detecting the full range and subtypes of large structural variants (SVs), greater than one kilobase in length, is challenging using clinically feasible next generation sequencing (NGS) technologies. Next generation mapping (NGM) is a new technology that allows for the interrogation of megabase length DNA molecules outside the detection range of single-base resolution NGS. In this study, we sought to determine the feasibility of using the Irys (Bionano Genomics Inc.) nanochannel NGM technology to generate whole genome maps of a primary prostate tumor and matched blood from a Gleason score 7 (4 + 3), ETS-fusion negative prostate cancer patient. With an effective mapped coverage of 35X and sequence coverage of 60X, and an estimated 43% tumor purity, we identified 85 large somatic structural rearrangements and 6,172 smaller somatic variants, respectively. The vast majority of the large SVs (89%), of which 73% are insertions, were not detectable ab initio using high-coverage short-read NGS. However, guided manual inspection of single NGS reads and de novo assembled scaffolds of NGM-derived candidate regions allowed for confirmation of 94% of these large SVs, with over a third impacting genes with oncogenic potential. From this single-patient study, the first cancer study to integrate NGS and NGM data, we hypothesise that there exists a novel spectrum of large genomic rearrangements in prostate cancer, that these large genomic rearrangements are likely early events in tumorigenesis, and they have potential to enhance taxonomy.

Association of Family History of Type 2 Diabetes with Prostate Cancer: A National Cohort Study

Background

Personal history of type 2 diabetes mellitus (T2DM) is associated with a lower incidence of prostate cancer, but the underlying mechanisms are largely unknown. We hypothesized that genetic factors that are involved in the development of T2DM might protect against prostate cancer.

Methods

We used a few Swedish registers, including the Swedish Multigeneration Register and the Cancer Register, to examine the risk of prostate cancer among men with a family history of T2DM. Standardized incidence ratios were used to calculate the relative risk.

Results

The overall risk of prostate cancer among men with a familial history of T2DM was 0.87 (95% CI: 0.86–0.89) as compared to matched controls. The risk was even lower for those multiple affected relatives with T2DM, and it was 0.86 for those with two affected relatives and 0.67 for those with three and more affected relatives.

Conclusion

Family history of T2DM was associated with a lower incidence of prostate cancer, and the risk was even lower for those with more than one affected relative. Our study strongly suggests that genetic factors or shared familial factors, such as obesity, that contributed to T2DM may protect against prostate cancer.