CD274 and neoplasm: Notably, autophagy-mediated PD-L1 degradation in Sigma1-expressing TNBC (sigma1 is a scaffolding protein involved in protein homeostasis in the endoplasmic reticulum (ER); it supports the increased protein synthesis demand associated with tumor growth) [70,71,72] and androgen-dependent prostate cancer cell lines contributed to tumor regression [73].