It stimulates the growth of KS lesions by stimulating the proliferation of spindle cells, activating cytokine genes (e.g. IL-6) and inhibiting IFN-γ-mediated apoptosis (Boshoff et al, 1995; Nicholas et al, 1997; Deregibus et al, 2002). This evidence concerns the gene IL6 and Kaposi's sarcoma.