Tumorigenesis of NIH3T3 cells induced by the exogenously over-expression of the novel tumor antigen OVA66 (P2121)

Abstract

Abstract The tumor associated antigen OVA66 which is firstly defined by serological analysis of human ovary cancer of recombinant cDNA expression library, has been demonstrated to be highly expressed in the majority of malignant tumors. We constructed a eukaryotic expression vector pFlag-OVA66 to establish an OVA66 stably over-expressed mouse fibroblast NIH3T3 cell line. The OVA66 over-expressed NIH3T3 cells exhibited several significantly malignant changes, the S and G2/M phage was markedly increased whereas the G1/G0 phage was decreased in the total cell cycle, indicating that the over-expression of OVA66 is able to promote cell cycling and proliferation. MTT and colony formation assay validated that OVA66 promotes the cell growth and colony formation in vitro. NIH3T3 cells with the over-expression of tumor antigen OVA66 displayed more resistance to the cell apoptosis induced by 5-FU. In vivo assay of the tumor xenograft studies in nude mice revealed the OVA66 over-expressed NIH3T3 cells were capable of forming tumors in the nude mice compared to the NIH3T3-mock cells with low expression of OVA66. Analysis of the phosphorylation of AKT and ERK1/2 stimulated with serum indicated a hyper activation of ERK1/2 MAPK and PI3K/AKT pathway in OVA66 stably over-expressed NIH3T3 cells. The results suggesting that OVA66 as a novel tumor antigen with its strong tumorigenic ability might be a novel target for the early detection, prevention and treatment of tumor in the future.