Effects of survivin shRNA-APC double gene co-expression lentiviral vector on subcutaneous xenotransplanted tumor of human HT-29 colon carcinoma in nude mice / 医学研究生学报

ABSTRACT

Objective Post-transcription RNA interference (RNAi) is more and more widely applied in multigene therapy.This study aimed to establish an subcutaneous xenotransplanted tumor (SXT) model of human HT-29 colon carcinoma in nude mice and investigate the effects of the survivin shRNA-APC double gene co-expression lentiviral vector on the growth of SXT.Methods Thirty-five nude mice were equally divided into five groups, double-gene survivin shRNA, survivin shRNA, APC, empty vector, and blank, and injected into the left anterior axillary with respective stably transfected cell lines and human HT-29 colon carcinoma cells, all at 2×106/mL, to establish an SXT model of human HT-29 colon carcinoma.The inhibition rate of tumor growth was calculated by measuring the size and weight of the SXT, the expressions of survivin mRNA and protein in the tumor tissue detected by real time PCR and immunohistochemistry respectively, and the apoptosis of the HT-29 colon carcinoma cells determined by TUNEL.Results The mean size and weight of the SXT were significantly reduced in the double-gene survivin shRNA-APC, survivin shRNA, and APC groups as compared with the blank and empty vector groups (P<0.05), though increased in the survivin shRNA and APC groups in comparison with the double-gene group (P<0.05).The expressions of survivin mRNA and protein in the tumor tissue were remarkably lower in the double-gene survivin shRNA-APC, survivin shRNA, and APC groups than in the blank and empty vector groups (P<0.05), even lower in the double-gene group than in the survivin shRNA, and APC groups (P<0.05).The apoptosis rate of the HT-29 colon carcinoma cells was markedly up-regulated in the double-gene survivin shRNA-APC ([56.72±3.17]%), survivin shRNA ([33.64±2.03]%), and APC groups ([31.19±1.79]%) as compared with the blank ([9.89±0.31]%) and empty vector groups ([10.06±0.43]%) (P<0.05), even more significantly in the double-gene than in the survivin shRNA and APC groups (P<0.05).Conclusion The survivin shRNA-APC double gene co-expression lentiviral vector can reduce the expression level the survivin gene, promote the apoptosis of colon carcinoma cells, and suppress the growth of the subcutaneous xenotransplanted tumor.