RNF180 suppressed aggressiveness by degrading NOTCH1, TRIM24 and FOXC1, and chemoresistance by degrading ACC1 and ACLY in colorectal cancer

Ring finger protein 180 ( RNF180 ) is an E3 ubiquitin-protein ligase that promotes polyubiquitination and degradation. We analyzed the roles and molecular mechanisms of RNF180 during the tumorigenesis and progression of colorectal cancer (CRC) through bioinformatics analysis, in vivo and vitro experiments. RNF180 overexpression was observed in CRC, and positively associated with T, N and TNM staging or differentiation. RNF180 inhibited proliferation, promoted apoptosis, and inhibited migration and invasion of CRC cells by interacting with and degrading NOTCH1, TRIM24 and FOXC1 via their ubiquitination and proteasomal degradation, and by inactivating Akt pathway. RNF180 might suppress the chemoresistance by mitigating lipid droplet assembly and ACC1- and ACLY- mediated lipogenesis in CRC cells via their ubiquitination and proteasomal degradation of ACC1 and ACLY. Its knockout might enhance the sensitivity of chemically-induced colorectal carcinogenesis in Lgr5-cre/RNF180 f/f mice. RNF180 -correlated genes were involved in neuroactive ligand-receptor interaction, glycosaminoglycan binding, ECM structural constituents and organization, receptor ligand activity, cell adhesion, mRNA splicing and so forth in CRC. The expression of RNF180 may be used as a biomarker for the diagnosis, as a prognostic indicator, and as a gene therapy target of CRC.