Human telomerase reverse transcriptase (hTERT) RNA and p53 tumour suppressor were previously suggested as useful targets for cancer gene therapy. In this study, we investigated the effects of systemically delivered adenoviruses harboring trans-splicing ribozyme that could target hTERT and induce p53 transcript in targeted cancer cells in vivo using mice with Hep3B human hepatocellular carcinoma cells that metastasized to the liver. We observed that intravenous injection of this virus (0.5 X1011 Virus) produced efficient regression of Hep 3B tumor metastasized nodules. Next we performed in vitro study to know whether it has a synergistic effects with CDDP, we observed that CDDP (2.5 ug/ml) increased cytotoxic effects in vitro given with the virus (10 MOI), but in vivo study revealed that addition of CDDP or arsenic hexoxide (As4O6) did not improve the therapeutic efficacy of the virus treatment. Next we performed toxicity test with 4 doses (0.5 X1011, 1 X1011, 2 X1011, and 5 X1011, Virus), which revealed that there were no toxic death, but 2-4 fold increased in AST and ALT with no changes in bilirubin, BUN, Creatinine levels. In conclusion, this study demonstrates that the adenoviruses harboring trans-splicing ribozyme targeting hTERT and inducing p53 transcript represents a safe and promising cancer treatment for hepatocellular carcinoma. [This study was supported by a grant from the National R&D Program for Cancer Control, Ministry for Health, Welfare & Family Affairs, Republic of Korea. (0820050), and National Research Foundation of Korea (NRF) grant funded by the Korea government(MEST) (20120002631).]
Keywords: Adenovirus, trans-splicing ribozyme, p53 tumour suppressor, Human Telomerase Reverse Transcriptase, cancer
Citation Format: Won Sup Lee, Hye Lim Kang, Arulkumar Nagappan, Jeong Won Yun, GonSup Kim, Soon Chan Hong, Sang-Jin Lee, In-Hoo Kim. Systemically delivered human telomerase reverse transcriptase (hTERT)-targeting p53-laden adenovirus shows strong antitumor effects in intrahepatic Hep3B xenograft mouse model. [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 3547. doi:10.1158/1538-7445.AM2015-3547