The role of CRP and ATG9B expression in clear cell renal cell carcinoma

The purpose of the study is to investigate the correlation between the expression of C-reactive protein (CRP) and autophagy-related 9B (ATG9B) and pathological features of clear cell renal cell carcinoma (CCRCC) patients. We also intended to explore the effects of manipulated expression of CRP and ATG9B on the apoptosis and cell cycle progression of CCRCC cell line. ATG9B expression in CCRCC tissues and adjacent renal tissues was analyzed by immunohistochemistry (IHC). Gene expression was determined at transcription and translational levels using real-time quantitative PCR (RT-qPCR) and Western blot. The association between CRP/ATG9B expression and clinical-pathological parameters including age, gender, pathological grades, TNM stage and distant metastasis of the patients was assessed by correlation analysis. siRNA and overexpression plasmids construction were used to manipulate the expression of CRP in human CCRCC cell line 786-O. Cell apoptosis and cell cycle progression were determined using flow cytometry (FCM) and Hoechst 33258 staining. CRP expression correlates with ATG9B expression. The expression of CRP and ATG9B are significantly correlated with TNM staging, distant metastasis, and survival time of CCRCC patients. A high-level of CRP indicates a poor overall survival (OS). In addition, CRP expression influences cell cycle and apoptosis of CCRCC cells. The study reveals that CRP might be a CCRCC development promoter. In addition, there is a close relationship between CRP and ATG9B in CCRCC carcinogenesis.