TGM2 and prostate cancer: Rottlerin-induced autophagy leads to apoptotic cell death by multiple signaling pathways, such as PKCδ/transglutaminase 2 (TG2)-dependent and -independent pathways in pancreatic cancer cells, PKCδ-independent mechanism in HT1080 human fibrosarcoma cells, and inhibition of PI3K/AKT/mTORC1 pathways in prostate cancer stem cells (CSCs) [138], breast CSCs [242] and human pancreatic CSCs [137].