Annexin A3 may play an important role in ochratoxin-induced malignant transformation of human gastric epithelium cells

Ochratoxin A (OTA), one of the most abundant food-contaminating mycotoxins, is a possible carcinogen to humans. We previously demonstrated that long-term (40 weeks) OTA exposure induces the malignant transformation of human gastric epithelium cells (GES-1) in vitro. However, the specific mechanism underlying OTA-induced gastric carcinogenesis is complex. In the present study, we used 2-DE and matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI/TOF MS) combined with bioinformatics and immunoblotting to investigate the differentially expressed proteins between GES-1 and OTA-malignant transformed GES-1 cells (OTA-GES-1_T cells) in vitro. We found that four differentially expressed proteins were identified after malignant transformation, including actin, cytoplasmic 1 (ACTB), F-actin-capping protein subunit alpha-1 (CAPZA1), Annexin A3 (ANXA3), thioredoxin peroxidase B from red blood cells (TPx-B) and Fibrinogen beta B (Fibrinogen β). Among the differentially expressed proteins, the effect of Annexin A3 was analyzed by MTT assay, western blot, cell cycle analysis, wound healing assay, Transwell assay, and colony formation assay in OTA-GES-1_T cells. The results showed that inhibition of Annexin A3 by siRNA effectively prevented the proliferation, migration, and invasion abilities of OTA-GES-1_T cells. Collectively, the results of this study will guide future research on OTA carcinogenicity.