DUSP4 inhibits autophagic cell death in PTC by inhibiting JNK-BCL2-Beclin1 signaling

This study aimed to explore the relationship between DUSP4 and JNK-mediated autophagic cell death in PTC. In this study, we explored the roles of DUSP4 in PTC using gain-of-function and loss-of-function assays. In addition, we further identified the significance of JNK-BCL2-Beclin1-autophagy signaling on DUSP4-regulated PTC carcinogenesis by combining DUSP4 silencing with JNK specific inhibitor (SP600125). We found that DUSP4 silencing promoted the phosphorylation of JNK and BCL2 in PTC cells and enhanced the release of Beclin1 from BCL2-Beclin1 complex. DUSP4 silencing promoted autophagy and death in PTC cells.The death and autophagy enhanced by DUSP4 silencing was reversed by JNK inhibitor. We further extended the in vitro experiments by injecting K1 cells transduced with DUSP4-silencing vector subcutaneously into nude mice. In vivo assays showed that DUSP4 silencing not only inhibited tumor growth, but also promoted JNK and BCL2 phosphorylation and LC3II expression.Overall, DUSP4 inhibits BCL2-Beclin1- autophagy signaling through negatively regulating JNK activity, thus inhibiting PTC oncogenesis.This study provides more potential clues for the prevention and cure of PTC.PMID:33621155 | DOI:10.1139/bcb-2020-0636
Source: Biochemistry and Cell Biology - Category: Biochemistry Authors: Source Type: research