These cells express lytic proteins, including vIL-6, vGPCR, and K1, and ultimately upregulate the expression of cellular inflammatory and angiogenic cytokines [250], including VEGF [251], IL-6, CXCL8 and bFGF, which play important roles in KS development in a paracrine fashion. This evidence concerns the gene KRT1 and Kaposi's sarcoma.