TCRP1 promotes radioresistance of oral squamous cell carcinoma cells via Akt signal pathway

Tongue Cancer resistance-associated protein 1 (TCRP1) is a novel gene located on human chromosome 11q13.4 which has been reported as a candidate related to chemotherapeutic resistance to cisplatin. Results suggest that TCRP also contribute to radioresistance in oral squamous cell carcinoma (OSCC) cells. We previously established exogenous overexpression of TCRP1 cell line Tca8113/TCRP1 and TCRP1 knockdown cell line Tca8113/PYM-siRNA and paired control cell lines, which provides a cell model system to investigate the roles and mechanisms of TCRP1-mediated radioresponse in OSCC. In this study, we first compared the radiosensitivity of up/down-regulating expression of TCRP1 cell lines and paired control cell lines by a clonogenic survival assay, Hoechst 33258 staining, cell growth assay, and comet assay. The results indicated that TCRP1 played a significant role in mediating OSCC radioresistance through decreased cells Apoptosis and increased cellular proliferation and long-term survival. The further study found that TCRP1 function by up-regulating Akt activity and levels and then elevating the level of NF-κB. In summary, these results provided strong evidence for the linkage between TCRP1 and radiation sensitivity and may provide theoretical base of TCRP1 as a potential molecular mark of estimating the response for irradiation in OSCC.