Association between RNASEL, MSR1, and ELAC2 single nucleotide polymorphisms and gene expression in prostate cancer risk.

BACKGROUND

There is contradictory evidence of the effects that environmental factors-dietary habits (ingestion rates of red meat, soy products, fish, etc.) and work environment (exposure to metals, pesticides, several toxic products, etc.)-and KLK3, AR, RNASEL, MSR1, and ELAC2 expression patterns have on prostate cancer (PCa). In our study, we investigated the potential association between KLK3, AR, RNASEL, MSR1, and ELAC2 polymorphisms, expression patterns, exposure to environmental factors, and PCa in a Spanish cohort. Blood and fresh tissue samples were collected from 322 subjects with prostate-specific antigen (PSA)>4ng/ml to determine their genotypes (RNASEL, MSR1, and ELAC2) and assess messenger ribonucleic acid expression levels (by quantitative amplification testing).

MAIN FINDINGS

Among clinical parameters, a 63.6% of patients with CC variants in rs11545302 (ELAC2) had PSA>20ng/ml (P = 0.008), and rs486907 (RNASEL), with 52.8% of patients with CT variants with Gleason score>7. Regarding TNM stage, patients with GG variants, rs4792311 (ELAC2) generally had stage 1 tumors. Genetic expression analysis revealed RNASEL (P = 0.007) was underexpressed in PCa tissue, whereas KLK3 (P = 0.041) was overexpressed. As to environmental factors, the intake of dried fruits (P = 0.036) and practice of sports (P = 0.024) revealed an effect in PCa. Moreover, environmental factors were observed to affect gene expression patterns. Thus, RNASEL (P = 0.018) and ELAC2 (P = 0.023) were found to be underexpressed in patients who ate processed foods frequently; MSR1 (P = 0.024) and AR (P = 0.004) were underexpressed in patients who did not practice sports; and KLK3 (P = 0.039; P = 0.046) underexpressed in patients exposed to dust and toxic products.

CONCLUSIONS

This is the first study to analyze the correlation between RNASEL, MSR1, and ELAC2 genotypes and messenger ribonucleic acid expression in PCa. RNASEL and KLK3 show different expression patterns in normal vs. tumor tissue, which supports their reported relevance in human cancer. The results obtained confirm that RNASEL plays a crucial role in PCa. Environmental factors such as exercise, exposure to toxic agents, and intake of processed foods are associated with PCa.