SQSTM1 and cancer: p62, also known as sequestosome 1 (SQSTM1), is a ubiquitin-binding protein involved in cellular signal transduction as well as a selective substrate of autophagy.254 p62 directly interacts with LC3 through the LC3-interacting region (LIR) within p62 to promote the formation of autophagosomes, while the inhibition of autophagy is accompanied by insufficient degradation of the p62 protein.255 Therefore, p62 and LC3 are widely established as markers of autophagy flux in cancer research.