Aberrant expression and localization of hnRNP‐A2/B1 is a common event in human gastric adenocarcinoma

Abstract

BACKGROUND AND AIM: Nuclear-matrix proteins can be proteomic markers for cancer lesions. The present study aimed to determine the roles of heterogeneous nuclear ribonucleoproteins--A2 and B1 (hnRNP-A2/B1) in human gastric carcinogenesis. METHODS: Human gastric cancer and non-cancerous tissues were collected for immunohistochemical analysis. Proteomics technique, Western blot, laser confocal microscope, and real-time quantitative reverse transcription-polymerase chain reaction were performed to determine the aberrant expression of nuclear-matrix proteins. RESULTS: hnRNP-A2/B1 existed in the nuclear matrix of gastric cancer cells, and its expression was enhanced in human gastric cancer and decreased by hexamethylene bisacetamide. The colocalization of hnRNP-A2/B1 with c-myc, c-fos, p53, and Rb was translocated from the nucleolus to the cytoplasm during the differentiation of tumor cells. CONCLUSIONS: hnRNP-A2/B1 affected tumor cell differentiation through interaction with oncogenes and tumor-suppressor genes, and it was overexpressed in human gastric cancer. We postulate that hnRNP-A2/B1 could serve as a biomarker for the diagnosis of human gastric cancer.