Background: We have explored a gene-therapeutic approach to stimulate antitumor immunity by adenoviral-mediated transfer of CD40 ligand (CD40L) to treat metastatic liver cancer in a rat model.
Materials and methods: Rat metastatic liver cancer cells were implanted into the back of rats bilaterally. When the larger tumor reached 8.0 mm in diameter, adenovirus vector-expressing mouse CD40L was injected intratumorally as treatment group (n=5), while LacZ was injected in the control group (n=5).
Results: In the control group, the tumor gradually grew to be 20.7+/-1.6 (mean+/-SD) mm in intratumorally injected tumors and 21.8+/-3.7 mm in opposite tumors seven weeks after injection, respectively. In contrast, in the treatment group, the tumor was reduced to 3.6+/-8.2 mm and 3.7+/-8.2 mm. The tumor growth and survival rate were significantly different (p<0.001).
Conclusion: Adenovirus vector-mediated CD40L gene therapy is an effective therapeutic method for metastatic liver cancer.