BACKGROUND: To study the effect and safety of tissue specific gene therapy of suicide gene for lung adenocarcinoma. METHODS: Retroviral vector of G1CEACDNa contained a carcinoembryonic antigen (CEA) promoter regulated cytosine deaminase expression cassete (CEA/CD). By means of infection of virus, tissue specific expressing vectors and non-specific expressing vectors were transfected into A549 cell, which was CEA-producing lung adenocarcinoma cell line and then xenografted in nude mice, and the anti-tumor effect was evaluated. Then the retrovirus was injected directly into the tumor mass on nude mice, and the sensitivity of the xenograft to G1CEACDNa/5-fluorocytosine (5-FC) and the side effects were observed. RESULTS: (1) After transfected and untransfected A549 cells were implanted into nude mice, there was no difference in tumor formation among all the groups. (2) After 5-FC administration, the tumor transfected with tissue-specific gene displayed a higher sensitivity to the drug than those treated with non-specific in vitro gene-therapy. (3) The tumor-bearing nude mice were randomized in a blind manner based on comparable size to receive the supernatant of recombinant retrovirus G1CEACDNa followed by 5-FC, and significant growth suppression could be observed. (4) Comparing to the group with injection of 5-fluorouracil (5-FU) alone, tissue-specific suicide gene therapy showed lower suppression to bone marrow. CONCLUSIONS: The results suggest that tissue-specific suicide gene therapy may play an important role in individual treatment of lung cancer.
BACKGROUND: To study the effect and safety of tissue specific gene therapy of suicide gene for lung adenocarcinoma. METHODS: Retroviral vector of G1CEACDNa contained a carcinoembryonic antigen (CEA) promoter regulated cytosine deaminase expression cassete (CEA/CD). By means of infection of virus, tissue specific expressing vectors and non-specific expressing vectors were transfected into A549 cell, which was CEA-producing lung adenocarcinoma cell line and then xenografted in nude mice, and the anti-tumor effect was evaluated. Then the retrovirus was injected directly into the tumor mass on nude mice, and the sensitivity of the xenograft to G1CEACDNa/5-fluorocytosine (5-FC) and the side effects were observed. RESULTS: (1) After transfected and untransfected A549 cells were implanted into nude mice, there was no difference in tumor formation among all the groups. (2) After 5-FC administration, the tumor transfected with tissue-specific gene displayed a higher sensitivity to the drug than those treated with non-specific in vitro gene-therapy. (3) The tumor-bearing nude mice were randomized in a blind manner based on comparable size to receive the supernatant of recombinant retrovirus G1CEACDNa followed by 5-FC, and significant growth suppression could be observed. (4) Comparing to the group with injection of 5-fluorouracil (5-FU) alone, tissue-specific suicide gene therapy showed lower suppression to bone marrow. CONCLUSIONS: The results suggest that tissue-specific suicide gene therapy may play an important role in individual treatment of lung cancer.