STAT1 and neoplasm: evPD-L1 has been reported to suppress anti-tumor immunity within the TME and at distant sites.19,20 In this study, we examined the mechanisms by which pharmacological inhibition of Sigma1 can interfere with the IFN-γ/STAT1 axis induced cell surface expression and incorporation of PD-L1 into EVs, two locations where PD-L1 can block antitumor immune responses.