Differential Gene Expression in Prostate Tissue According to Ejaculation Frequency

In a prospective study of 31 925 men with 18 yr of follow-up, higher ejaculation frequency (EF) throughout adulthood was associated with lower rates of prostate cancer. To further explore this association, we evaluated whole transcriptome gene expression in the prostate tissue from study participants who developed prostate cancer between 1992 and 2004 (n=157 tumor tissue, n=85 adjacent normal). We tested for trends in gene expression according to the level of EF as self-reported in 1992 for ages 20-29 yr, 40-49 yr, and the year prior to the questionnaire, 1991. There were no associations between EF and gene expression in areas of tumor after accounting for multiple testing. In contrast, in the adjacent normal tissue, 409 genes and six pathways were differentially expressed at a false discovery rate ≤0.2 across categories of EF in 1991. These results suggest that ejaculation affects the expression of genes in the normal prostate tissue. The identified genes and pathways provide potential biological links between EF and prostate tumorigenesis.

To explore previous findings that men who ejaculate more frequently have lower risk of prostate cancer, we evaluated molecular alterations in the prostate tissue according to each man's frequency of ejaculation prior to diagnosis. We identified biological processes that could link ejaculation frequency and prostate cancer.

European urology. 2018 May 18 [Epub ahead of print]

Jennifer A Sinnott, Katherine Brumberg, Kathryn M Wilson, Ericka M Ebot, Edward L Giovannucci, Lorelei A Mucci, Jennifer R Rider

Department of Statistics, The Ohio State University, Columbus, OH, USA; Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA, USA., Yale University, New Haven, CT, USA., Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA, USA; Channing Division of Network Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA., Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA, USA., Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA, USA; Channing Division of Network Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA; Department of Nutrition, Harvard T.H. Chan School of Public Health, Boston, MA, USA., Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA, USA; Department of Epidemiology, Boston University School of Public Health, Boston, MA, USA. Electronic address: .