We propose that the fact that tumorigenic K-Pα(+)S KS cells showed enhanced expression of KSHV lytic genes while they are able to growth in vivo, together with the results showing proliferation of productively KSHV-infected human MSC cultures of Fig 7, provides a powerful model for the initial steps of KSHV oncogenesis showing a definitive oncogenic role of KSHV lytic gene expression in KS pathogenesis. The gene discussed is LRP1; the disease is Kaposi's sarcoma.