Purpose: To value the therapeutic effect of PUMA gene mediated by by radiation-inducible promoters in the treatment of Xenograft of human tongue squamous carcinoma in naked mice.

Methods: Eukaryotic cell expression recombinant pcDNA3.1(+)/E-PUMA was constructed. The model of transplanted Tca8113 cell line in naked mice was founded. The plasmids pcDNA(+)3.1/E-PUMA were transfected into tumors by lipofectamine. 24 h later, the tumors were treated by 3 Gy irradiations. Animals were monitored for volume of tumors at regular intervals. PUMA mRNA was detected by RT-PCR. PCNA and Apoptosis were detected by immuno-histiochemical method and in situ end-labeling respectively. The data was analyzed by SPSS11.0 software package for chi-square test.

Results: The tumors were suppressed obviously by radiation-inducible promoters mediated PUMA gene. The 3 Gy radiation could up-regulated the PUMA expression in xenograft of human tongue squamous in naked mice. There was significant difference between the apoptosis proliferation index (PI) or index (AI) in tumors between therapy group and control groups ( P < 0.01).

Conclusions: The radiation-inducible promoters can be served as a molecular switch to improve the expression of PUMA gene in transplanted human tongue squamous carcinoma in naked mice, and low dose induction radiation can significantly improve the therapeutic efficiency. It will be possible to validate this strategy in the targeted treatment of tongue suqmous cell carcinoma.