Genetic ancestry and prostate cancer susceptibility SNPs in Puerto Rican and African American men.

BACKGROUND: The Puerto Rican (PR) population is a racially admixed population that has a high prostate cancer (PCa) mortality rate. We hypothesized in this pilot study that West African Ancestry (WAA) was associated with PCa in this heterogeneous (PR) population. METHODS: A case/case and case/control study was performed. Controls, 207 African American (AA) and 133 PR were defined as men with no PCa, a serum PSA < 2.5 ng/mL and a negative rectal examination. Cases were patients with pathological specimens from radical prostatectomies (RP) (291 PR and 200 AA). DNA was extracted from whole blood of controls and from paraffin embedded normal seminal vesicle from the RPs. We assessed the association of PCa and aggressiveness with genetic ancestry using an ancestry informative marker panel (AIMs) and Wilcoxon rank-sum test and the association of PCa and aggressiveness with 15 previously PCa associated SNPs using Chi square test. Gleason Score (GS) and tumor stage (TS) were used to define low risk (GS ≤ 7[3 + 4]), TS ≤ pT2) and high risk (GS≥ 7[4 + 3], TS > pT2) PCa. Statistical analyses were done using SAS. RESULTS: No difference in overall percent WAA was found between PR cases and controls. Among PR or AA cases WAA was not associated with disease severity based upon risk group, Gleason score or stage. Among AA controls WAA was significantly higher than in cases. The SNP rs7824364 (chromosome 8q24) PCa risk allele was significantly increased among cases versus controls for both AA (P < 0.0001) and PR (P = 0.0001) men. PR men with ≥1 risk allele exhibited a higher percent of WAA (39% vs 29%, P = 0.034). CONCLUSION: The SNP rs7824364, a local marker of WAA in the 8q24 region was associated with PCa among both AA and PR men and with increased WAA among PR men. This novel relationship of PCA risk loci, WAA with PCa and its phenotype among PR men deserves further study.

Association of serum lipid levels and prostate cancer severity among Hispanic Puerto Rican men.

BACKGROUND: While obesity and fat intake have been associated with an increased risk of prostate cancer (PCa) aggressiveness and mortality, the association between lipid levels and PCa phenotype remains unclear. Previous reports evaluating this association are inconsistent and highly variable when considering different racial/ethnic groups. There are scarce data regarding this association among Hispanics, and specifically Puerto Rico's Hispanic men, a population with a higher burden of PCa, metabolic syndrome and overweight. This population has a different ancestry profile than other Hispanics from Central and South America. Due to the above the researchers inquired if there is a relationship between serum lipid levels and PCa phenotype in this understudied population using a cohort of patients treated with radical prostatectomy as their first treatment. METHODS: We performed an exploratory retrospective medical record review study of 199 PCa patients who underwent radical prostatectomy between 2005 and 2012. Variables analyzed included age at PCa diagnosis, Body Mass Index (BMI), preoperative serum prostate-specific antigen (PSA), lipid levels, and clinical parameters such as prostatectomy pathologic stage and Gleason Score (GS). PCa severity was defined using pathologic stage and GS. Unadjusted and adjusted logistic regression models were fitted to estimate the odds ratios (ORs) with 95 % confidence intervals (CI) to define the relationship among clinical characteristics and PCa severity. RESULTS: Mean age for the cohort was 58.8 years (range: 40-75), 78.9 % were overweight or obese, 36.7 % had hypertriglyceridemia, and 35.2 % had low HDL levels. In the unadjusted logistic regression model, hypertriglyceridemia (OR: 2.11, 95 % CI = 1.13-3.93), low HDL (OR: 1.90, 95 % CI = 1.02-3.56-), and age (OR: 2.34, 95 % CI 1.25-4.40) were significantly associated with a diagnosis of high severity of PCa. CONCLUSIONS: In Puerto Rican men with PCa, elevated hypertriglyceridemia, low HDL levels, and age were statistically associated with high grade PCa on bivariate analysis. Total cholesterol level was not associated with severity of disease. Associations lost significance upon multivariate adjustment. These data generate important hypotheses regarding the potential relationship between lipid pathways and PCa development and underscore the need to perform larger scale and longitudinal studies to sort out whether, hypertriglyceridemia is associated with PCa phenotype and development.

Impact of FTO SNPs rs9930506 and rs9939609 in Prostate Cancer Severity in a Cohort of Puerto Rican Men.

BACKGROUND: Obesity is prevalent in PR and has been associated with prostate cancer (PCa) mortality and aggressiveness. Polymorphisms (SNPs) rs9930506 and rs9939609 in the FTO gene have been associated with both obesity and PCa. The aim of this work was to ascertain whether the presence of these SNPs is associated with PCa risk and severity in a cohort of Puerto Rican men. METHODS AND FINDINGS: The study population consisted of 513 Puerto Rican men age ranging from 40-79 years old who underwent radical prostatectomy (RP) as the first treatment for PCa and 128 healthy Puerto Rican men age ranging from 40-79 years old. Genomic DNA (gDNA) was extracted and SNPs were determined by Real-Time PCR. PCa severity was defined based on RP stage and Gleason Score. The relationship of FTO SNPs with demographic, clinical characteristics, PCa status and PCa severity were assessed. Logistic regression models with a 95% confidence interval (CI) determined SNPs interaction with PCa risk and severity odds ratio (ORs). RESULTS AND DISCUSSION: BMI, age and PSA were considered as confounders. Hardy-Weinberg equilibrium was present for both SNPs. The heterozygous forms (A/G; T/A) were the most prevalent genotypes and the frequency of alleles and genotypes for both SNPs agreed with those published in 1000 genomes. Results suggest an inverse association between the mutated rs9939609 and the risk of having PCa (OR: 0.53, 95% CI: 0.31-0.92) and a positive association with overweight (OR: 1.05, 95% CI: 0.68-1.62). Importantly, among the cases that were overweight, those with mutated rs9939609 had a greater chance of high severity PCa (OR: 1.39, 95% CI: 0.84-2.32) although these results were not statistical significant upon adjustment. Limitations of the study were the relatively small cohort and lack of access to the weight history of all our subjects. CONCLUSION: Results offer a research line to be followed with an expanded number of subjects that may provide a better statistical significance, to unravel the high mortality rate in this population.