Tas is a drug with selective neutralizing activity against secreted S100A8/9.[38, 39] It has recently emerged as a therapeutic agent for cancer and has been shown to prolong the progression‐free survival prostate cancer patients.[40] We are the first to discover that Tas inhibited the expression of endogenous S100A9 in tumor cells. The gene discussed is S100A9; the disease is Familial prostate cancer.