DEPDC1 up-regulates RAS expression to inhibit autophagy in lung adenocarcinoma cells.

DEP domain containing 1(DEPDC1) is involved in the tumorigenesis of a variety of cancers. But its role in tumorigenesis of lung adenocarcinoma (LUAD) is not fully understood. Here, we investigated the role and the underlying mechanisms of DEPDC1 in the development of LUAD. The expression and prognostic values of DEPDC1 in LUAD were analysed by using the data from public databases. Gene enrichment in TCGA LUAD was analysed using GSEA software with the pre-defined gene sets. Cell proliferation, migration and invasion of A549 cells were examined with colony formation, Transwell and wound healing assays. The function of DEPDC1 in autophagy and RAS-ERK1/2 signalling was determined with Western blot assay upon DEPDC1 knockdown and/or overexpression in A549, HCC827 and H1993 cells. The results demonstrated that DEPDC1 expression was up-regulated in LUAD tissues, and its high expression was correlated with unfavourable prognosis. The data also showed that DEPDC1 knockdown impaired proliferation, migration and invasion of A549 cells. Most notably, the results showed that DEPDC1 up-regulated RAS expression and thus enhanced ERK1/2 activity, through which DEPDC1 could inhibit autophagy. In conclusion, our study revealed that DEPDC1 is up-regulated in LUAD tissues and plays an oncogenic role in LUAD, and that DEPDC1 inhibits autophagy through the RAS-ERK1/2 signalling in A549, HCC827 and H1993 cells.