Previous studies have shown that C. acnes has the capability to stimulate secretion of IL6 and CXCL8 by prostate epithelial cells in vitro [16, 21, 22], and a microenvironment containing high levels of these two inflammatory mediators has been associated with prostate cancer progression [6–8, 10, 11]. The gene discussed is CXCL8; the disease is prostate cancer.