SQSTM1 and gastric cancer: Xu et al. (2018a) have shown that Rab5a expression level is positively associated with drug resistance in gastric cancer cells. It has been found that Rab5a overexpression increases the phosphorylation level of mTOR, decreases the LC3-II/I ratio, and increases p62 expression level, thereby inhibiting autophagy and inducing DDP resistance, whereas Rab5a knockdown can facilitate autophagy and reverse DDP resistance in vitro (Xu et al., 2018a).