SMPD3 and prostate cancer: Additionally, in the prostate cancer model, the mice injected with mutant cells deleted of PD-L1, Rab27a, or nSMase2 survived more than 90 days, whereas the mice injected with WT cells died soon or had to be euthanized because of tumors greater than 2 cm in diameter (Poggio et al., 2019).