[Selective cytotoxic effect of lentivirus-mediated double suicide gene transfer on human gastric adneocarcinoma cells].
OBJECTIVE
To study the selective cytotoxic effect of lentivirus-mediated double suicide gene (CD/TK) against human gastric carcinoma cells SGC-7901 in vitro.


METHODS
SGC-7901 cells were infected with FGW-KDRP-CD/TK vector and the infection efficiency was observed under a fluorescence microscope. The morphological changes of the infected cells were observed by Giemsa staining. Flow cytometry (FCM) was employed for cell cycle analysis, and the expression of CD/TK was detected by RT-PCR. The infected cells were then treated with the prodrugs ganciclovir (GCV) and/or 5-fluorocytosine (5-FC) at different concentrations, and the cytotoxic effects were evaluated using MTT method.


RESULTS
The infection efficiency of the lentiviral vector in SGC-7901 cells increased with the titer of the virus, which produced no significant effect on the cancer cell morphology in vitro or on the percentages of G0-G1, G2-M and S phase cells (P>0.05). RT-PCR demonstrated the expression of CD/TK gene in SGC-7901 cells infected by FGW-KDRP-CD/TK. The infected cells were highly sensitive to the prodrugs with a dose-dependent cytotoxic effect within a specific concentration range of the drugs, whereas the non-infected cells were not sensitive to the prodrugs. Combined use of the two prodrugs produced an obviously stronger inhibitory effect than either of the them (P<0.05). When combined, GCV and 5-FC at the concentration of 0.1+40, 1+80, 10+160, and 100+320 mg/L demonstrated a synergetic effect with a CDI<1.


CONCLUSIONS
Lentivirus-mediated CD/TK fusion gene system can selectively kill gastric cancer cells, and the two prodrugs show a synergistic cytotoxic effect.
Kong
Heng
H
Department of Breast and Thyroid Surgery, Sixth Hospital of Shenzhen, Shenzhen, 510282, China. generaldoc@ 126.com
Huang
Zong-hai
ZH
Chen
Hai-jin
HJ
Li
Qiang
Q
Tao
Lin-yu
LY
Qi
Ke
K
D000230:Adenocarcinoma / Q000235:genetics / Q000473:pathology; D045744:Cell Line, Tumor; D043525:Cytosine Deaminase / Q000096:biosynthesis / Q000235:genetics*; D003603:Cytotoxins / Q000494:pharmacology; D041722:Genes, Transgenic, Suicide / Q000235:genetics*; D015316:Genetic Therapy; D005822:Genetic Vectors / Q000235:genetics; D006801:Humans; D016086:Lentivirus / Q000235:genetics* / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis / Q000235:genetics / Q000494:pharmacology; D013274:Stomach Neoplasms / Q000235:genetics / Q000473:pathology*; D013937:Thymidine Kinase / Q000096:biosynthesis / Q000235:genetics*; D040301:Vascular Endothelial Growth Factor Receptor-2 / Q000235:genetics / Q000378:metabolism
D003603:Cytotoxins; D011993:Recombinant Fusion Proteins; D013937:Thymidine Kinase; D040301:Vascular Endothelial Growth Factor Receptor-2; D043525:Cytosine Deaminase