SENP1 Knockdown Suppresses Tumor Progression in Lung Adenocarcinoma by Regulating AAR Genes Expression

Abstract

Background SUMO specific peptidase 1(SENP1) is an important factor involved in the regulation of small ubiquitin-related modifier (SUMO) modification. Our previous research has shown that SENP1 could be a potential tumor-promoting factor in non-small cell lung cancer (NSCLC). However, its role in tumor progression remains largely unknown. This study aims to characterize the role of SENP1 in lung adenocarcinoma. Methods The TCGA database provided us expression profiles of SENP1 and overall survival rates. loss-of-function assays were performed to examine the effect of SENP1 on proliferation, migration and invasion of lung adenocarcinoma cells in vitro and in vivo. Immunoprecipitation (IP), western blot and quantitative real time PCR (qRT-PCR) were carried out to reveal the interrelation between SENP1, SIRT6 and AAR (amino acid response) genes signal pathway. Results In this study, we found that SENP1 was expressed at high levels in lung adenocarcinoma tissues and advanced TNM stages and was significantly associated with poor prognosis. we also found that SENP1 knockdown inhibited lung adenocarcinoma cell progression in vitro and in vivo. SUMOylation of SIRT6 was also observed in lung adenocarcinoma, and it was reduced by SENP1. SUMOylation of SIRT6 specifically increased its deacetylation of histone H3 on lysine 56 instead of that of lysine 9 (H3K9) in an in vitro model. Mechanistically, we found that knockdown of SENP1 reduced the expression of AAR genes by decreasing H3K56 acetylation through increasing SIRT6 SUMOylation. Moreover, mutation of the SUMOylation sites of Sirt6 reduced its tumor-suppressive effects. Conclusions These results revealed that SENP1 promotion of tumor progression in lung adenocarcinoma and its tumor-promoting effects might be attributed to its important role in the regulation of Sirt6 SUMOylation and the expression of AAR genes.