RNAi-MEDIATED SUPPRESSION OF PUTATIVE TUMOR SUPRESSOR S100A2 IN HUMAN BRONCHIAL EPITHELIAL CELLS

Abstract

S100A2 is a member of the S100 calcium-binding proteins, but the mechanism of its action is not clear. The expression of this protein has been reported to be associated with the prognosis in patients with laryngeal squamous cell carcinoma and to be accompanied by malignant changes in an in vitro bronchial epithelial carcinogenesis model. To know whether S100A2 has a tumor suppressive function in this model system, we applied RNA interference to suppress the S100A2 expression in 1799 immortalized human bronchial epithelial cells. The cells transfected with the vector expressing small hairpin RNA specific to the S100A2 gene showed the depletion of S100A2. The 1799 cells without S100A2 expression exhibited malignant phenotypes such as a colony forming ability and resistance to anoikis. These results support the hypothesis that S100A2 serves as a tumor suppressor in this system. (134 words)