Endoglin (CD105) Silencing Mediated by shRNA Under the Control of Endothelin-1 Promoter for Targeted Gene Therapy of Melanoma

Endoglin (CD105), a transforming growth factor (TGF)-β coreceptor, and endothelin-1, a vasoconstrictor peptide, are both overexpressed in tumor endothelial and melanoma cells. Their targeting is therefore a promising therapeutic approach for melanoma tumors. The aim of our study was to construct a eukaryotic expression plasmid encoding the shRNA molecules against CD105 under the control of endothelin-1 promoter and to evaluate its therapeutic potential both in vitro in murine B16F10-luc melanoma and SVEC4-10 endothelial cells and in vivo in mice bearing highly metastatic B16F10-luc tumors. Plasmid encoding shRNA against CD105 under the control of the constitutive U6 promoter was used as a control. We demonstrated the antiproliferative and antiangiogenic effects of both plasmids in SVEC4-10 cells, as well as a moderate antitumor and pronounced antimetastatic effect in B16F10-luc tumors in vivo. Our results provide evidence that targeting melanoma with shRNA molecules against CD105 under the control of endothelin-1 promoter is a feasible and effective treatment, especially for the reduction of metastatic spread.