TCRP-1 (Tongue Cancer Resistance-related Protein-1) gene was recently cloned from the multidrug resistance tongue cancer cell (Tca8113/PYM) which developed by ourselves team (GeneBank accession number: EF36480). Subsequently we found that the gene can mediate tongue cancer cells to specific cisplatin chemotherapy tolerance and radiotherapy tolerance, and its mechanism may be caused at least in part by TCRP1 induced activation of the PI3K/Akt/NF-κB signaling pathway and promotes cell survival. Recently, using real-time quantitative PCR and immunohistochemical method to detect various types of tumors and control normal tissue, we found that expression of TCRP1 in lung cancer, ovarian cancer and glioma were significantly higher than that of normal tissue. These results suggest that TCRP1 gene may be closely related to the carcinogenesis. In the present study we constructed a lentiviral vector expressing TCRP1 to transfect NIH/3T3 cells, and found proliferation rate of NIH/3T3/TCRP1 cells was significantly improved compared with NIH/3T3 cells and NIH/3T3/vector cells by detection with the CellTiter-Glo Assay. Clonogenic capacity of NIH/3T3/TCRP1 cells was 5.39 times and 20.18 times higher than the control group in plate cloning and soft agar cloning assay. Subcutaneous tumorigenicity experiment with self-controlled in 10 nude mice found only the injected site of NIH/3T3/TCRP1 cell emergence nodular masses about 1cm diameter after 3 weeks, and the tumorigenic rate was 90%. Pathological diagnosis of mass was fibrosarcoma. These results suggest that TCRP1 gene own an oncogene-like effect. In order to study the TCRP1 tumorigenic mechanisms, gene chips were used and showed that expression of total of 1894 genes were up-regulated and 3626 genes were down-regulated. Among these genes, the verification results of PDPK1, Akt, GSK3β and cyclinD1 were consistent with microarray results. Co-immunoprecipitation assay indicate that TCRP1 interact with PDPK1; FRET(Fluorescence Resonance Energy Transfer)experiments shows that TCRP1 can directly bind to PDPK1. On the other hand, the growth rate and in vitro colony forming ability of NIH/3T3/TCRP1 cells was significantly inhibited after using PDPK1 inhibitor AR-12 and TCRP1 interference. These data suggest that TCRP1 mediated PI3K/Akt pathway to the excessive activation by recruiting recruitment and activating of PDPK1, resulting in a series of growth and proliferation and cell transformation related factor expression or activation of its downstream. This may be the possible mechanism of cell malignant transformation induced by TCRP1.

{This study was supported by grant from National Natural Science Foundation (81472184) of China.}

Citation Format: Chengkun Wang, Xiaorong Liu, Qinwei Qiu, Zhijie Zhang, Jiang Yin, Guopei Zheng, Zhimin He. TCRP1 gene promotes NIH/3T3 cell transformation by over-activating PDPK1 and Akt. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2719. doi:10.1158/1538-7445.AM2015-2719