The Inhibition Of Hepatic Transplantation Tumor Growth By KDR-RNAi In Vivo

As the postulate of the growth, invasion and metastasis, angiogenesis of tumor has become the key target for the modern biological therapy. In HCC, angiogenesis and growth of tumor induced by VEGF possess a very intimate affinity with expression of KDR in HCC. KDR is the main receptor for VEGF to turn in adjusting angiogenesis. It play a very important role in angiogenesis of tumor induced by VEGF. The blocking of KDR signal transduction can inhibit neovascularization induced by tumor, then inhibit the growth and metastasis of tumor. RNA interfere technique is a brand new research method in genic function and therapy. RNAAi possess a high specificity compared with traditional genic research and therapy, such as antisense oligonucleotide therapy, it can distinguish to the accuracy of a single ribonucleotide; it inhibit the gene with the pattern of catalysis and enlargement, so it possess 10 times of specificity and efficiency than antisense gene; it also possess good points of high stability, easy anthrocytosis, low toxicity etc. Anti-angiogenesis of tumor with KDR siRNA provide a more effective access for the treatment of HCC, lay a research foundation for KDR function and oncotherapy.This project construct KDR siRNA with the application of RNA interference technique, establish subcutaneous transplantable tumor mouse model of HHCC. Inject KDR siRNA into tumor and observe the influence on growth of transplantable tumor and expression of KDR, which can lay a strong foundation for gene therapy of tumor induced by KDR.Methods and results:1. Establish subcutaneous transplantable tumor mouse model of HHCC in vivo. The volume of transplantable tumor and Doppler ultrasonic testing confirm the success of mouse model construction.2. Design and construct siRNA, The result of identify and sequencing show that three groups KDR siRNA were single enzyme chopped and come with two pieces 713bp, 5480bp and 2403bp, 3790bp, the same results as expected. Sequencing results are also consistent with the according KDR-siRNA order. The construction of siRNA works well.3. Observe the inhibition effect of three kinds of KDR RNAi to HCC in the subcutaneous transplantable tumor mouse model. All the mice tolerant to the injection, poor growth of tumor happen in treatment group of KDR-siRNA1,2 and 3, treatment group pf PGCsi.H1 possess nearly the same tumor growth rate with matched group.4. Detect expression of KDR with immunohistochemistry method. KDR of all groups express positive, but the degree is different. Strong positive KDR expressed by model set. Compared with which, KDR-siRNA1,2 and 3 can down grade the expression of tumor KDR (P<0.01, P<0.05).KDR siRNA plasmid has been constructed succeeded and this plasmid can slow down the growth of HHCC transplantable tumor of mouse, possess an obvious inhibition in growth of tumor. That lay a strong foundation for gene therapy of tumor induced by KDR.