Ovarian Cancer Gene Therapy By Lentivirus-Mediated RNA Interference Inhibiting The Expression Of VEGF-A And CXCR4

Objective: Stable inhibition of VEGF-A and CXCR4 in human ovarian cancer by RNA interference based on lentivirus delivery in vitro and in vivo, and observe the changes of hyperplasy and invasion as well as metastasis of ovarian cancer when VEGF and CXCR4 were down-regulated , hoping to find a effective treatment could be used in both basic research and clinical therapy.Methods: (1) Followed the service of E-RNAi, we designed and constructed kinds of siRNA which aimed VEGF-A and CXCR4 gene, and loaded them into FIV-based Lentivector Expression System which has both U1 and H1 promoters , verified by gene sequencing. (2) Transfected them into human ovarian cancer cells line sw626 in vitro, detected the VEGF-A and CXCR4 expression by Real time PCR and Western blot, detected the change of hyperplasy by CCK8, the abilities of invasion was detected by Matrigel invasion assay. (3) Injecting the tumor cells which had been transfected by vectors to make nude mouse model of ovarian cancer. When the level of target genes were knocked down, the numbers and size of tumor body were measured, observed the change of hyperplasy and metastasis of the tumor. The microvessel density (MVD) was detected by CD34 immunostaining and the apoptosis was investgated by Tunel.Results: (1) We got kinds of VEGF and CXCR4 specific siRNA Lentivector expression vectors and their gene sequence were correct.(2) We found they could efficiently inhibit the expression of target genes'expression in sw626 cells line in vitro. The proliferation of tumor cells were depressed when VEGF was down-regulated, the abilities of invasion was weaken when CXCR4's expression was inhibited.(3) The similar results were also got in vivo, the size of tumor was grown down and the number of tumors was decreased when the relative target gene was inhibited, meanwhile the MVD was descented and apoptosis was increased.Conclusion (1) We got kinds of VEGF and CXCR4 specific siRNA Lentivector expression vectors, which can inhibit target genes expression notably. (2)While the VEGF-A was knocked down, the proliferation of tumor cells were depressed, the size of tumor was grown down. (3)While the CXCR4 was knocked down, the abilities of invasion was weaken, the volume of tumors was also decreased.