Cationic liposome-mediated transfection of CD40 ligand gene inhibits hepatic tumor growth of hepatocellular carcinoma in mice.
OBJECTIVE
To evaluate the efficacy of cationic liposome-mediated CD40 ligand (CD40L) gene therapy for hepatocellular carcinoma.


METHODS
1x10(6) of parental H22 cells or H22 cells transfected with the expression vector containing murine CD40L cDNA encoding the entire coding region (pcDNA3.1(+)-mCD40L) were inoculated subcutaneously into the left flanks of syngenic BALB/C mice. The tumor-bearing mice (tumor nodules 10 mm in maximal diameter) received the treatment of the intratumoral injection of pcDNA3.1(+)-mCD40L/Transfectam, pcDNA3.1(+), or phosphate-buffered saline (PBS), or no treatment. The mice were monitored for tumor growth weekly. We examined mCD40L messenger ribonucleic acid (mRNA) expression by reverse transcription polymerase chain reaction (RT-PCR) and the histologic changes in tumors at two weeks after intratumoral injection using immunohistochemical staining of tumor tissues.


RESULTS
All mice inoculated with parental H22 cells developed a tumor subcutaneously, and the tumor size increased progressively within three weeks. However, the mice receiving H22-CD40L cells exhibited complete regression of the tumor two weeks after tumor cell inoculation. The tumor-bearing animals with the treatment of pcDNA3.1(+) or PBS, or without treatment had progressive tumor growth, while those mice treated with pcDNA3.1(+)-mCD40L exhibited a significant inhibition of tumor growth. RT-PCR analysis showed that 783-bp fragments corresponding to the mCD40L mRNA were amplified only from pcDNA3.1(+)-mCD40L treated tumors. The tumor samples from pcDNA3.1(+)-mCD40L-treated mice showed significant lymphocyte infiltration, apoptotic bodies, and confluent necrosis in the tumor tissues.


CONCLUSIONS
The tumorigenicity of CD40L-expressing cells was abrogated when the cells were implanted subcutaneously. In vivo gene therapy of established liver tumor nodules in mice by the intratumoral injection of pcDNA3.1(+)-mCD40L led to significant tumor inhibition. There was mCD40L mRNA expression in the tissues from pcDNA3.1(+)-mCD40L-treated tumors. The intratumoral injection of pcDNA3.1(+)-mCD40L induced a strong inflammatory, mainly lymphocytic infiltration of the tumor, and increased the necrotic rate of the neoplastic cells.
Jiang
Yong-fang
YF
Center for Liver Diseases, the Second Xiangya Hospital, Central South University, Changsha, China. jiangyongfang@hotmail.com
Ma
Jing
J
He
Yan
Y
Zhang
Yong-hong
YH
Xu
Yun
Y
Gong
Guo-zhong
GZ
D000818:Animals; D023201:CD40 Ligand / Q000235:genetics / Q000627:therapeutic use*; D006528:Carcinoma, Hepatocellular / Q000473:pathology* / Q000628:therapy*; D002412:Cations; D049109:Cell Proliferation; D005260:Female; D015316:Genetic Therapy / Q000379:methods*; D008081:Liposomes / Q000737:chemistry*; D008113:Liver Neoplasms / Q000473:pathology* / Q000628:therapy*; D051379:Mice; D008807:Mice, Inbred BALB C; D014162:Transfection / Q000379:methods; D016896:Treatment Outcome
D002412:Cations; D008081:Liposomes; D023201:CD40 Ligand