The roles of APOBEC3B in gastric cancer.

Gastric cancer was the third cause of death in China. In this study, we found that the APOBEC3 (apolipoprotein B mRNA-editing enzyme, catalytic polypeptide-like 3) expression was higher in gastric cancer tissues than that in normal tissues and confirmed APOBEC3B expression was correlated with the unfavorable prognosis of the patients with gastric cancer. Furthermore, APOBEC3B expression was associated with gender, tumor size, histological grade, T stage, and TNM staging of the patients with gastric cancer. Down-regulation of APOBEC3B expression in MNK28 cells could enhance the cytotoxicity of PDCD2. No editing took place in PDCD2 positive MKN28 cells with APOBEC3B shRNA. These results indicated that loss of function of PDCD2 may be partly caused by APOBEC3B-induced extensive mutagenesis.