Abstract
OBJECTIVES: To investigate the expression of CDKN3 in gastric cancer and its impact on prognosis of gastric cancer patients. METHODS: We analyzed CDKN3 expression in clinical specimens from 114 gastric cancer patients and assessed its association with 5-year postoperative survival of the patients. GO and KEGG enrichment analyses were used to predict the biological function and possible mechanism of CDKN3. The effects of lentivirus-mediated CDKN3 knockdown on biological behaviors of gastric cancer cells were evaluated using Transwell assay, CCK-8 assay, TUNEL staining, flow cytometry, and Western blotting. RESULTS: CDKN3 expression was significantly higher in gastric cancer tissues than in the adjacent tissues with significant correlations with CEA level, CA19-9 level, and T and N staging (P<0.05). High CDKN3 expression was an independent risk factor affecting 5-year postoperative survival of the patients and predictive for long-term prognosis (P<0.01). Enrichment analyses suggested a probable association of CDKN3 with apoptosis. In MGC-803 cells, CDKN3 knockdown significantly lowered migration and invasion capacities of the cells, while CDKN3 overexpression produced the opposite effects. TUNEL staining revealed a significantly lower level of cell apoptosis in gastric cancer tissues than in adjacent tissues (P<0.01). CDKN3 knockdown obviously inhibited proliferation and increased apoptosis of MGC-803 cells. CDKN3 overexpression down-regulated the expressions of p53, p21 and Bax and up-regulated the expressions of p-p65 and Bcl-2. CONCLUSIONS: CDKN3 is highly expressed in gastric cancer tissues and affects patient prognosis. CDKN3 overexpression promotes proliferation, invasion and migration and suppressed apoptosis of gastric cancer cells possibly through the p53/NF-κB signaling pathway.