TMPRSS2 and prostate cancer: TMPRSS2 plays a key role in prostate cancer and its gene expression is strongly upregulated by androgens.6 Thus, anti-androgens widely used in prostate cancer treatment can downregulate TMPRSS2 cell expression thus providing relative protection of this category of (generally elderly) patients for SARS-Cov-2 vulnerability, as recently reported by Montepoli and co-workers.7 Also, the extent to which TMPRSS2 expression can be modulated by other anti-cancer treatments remains to be explored.