There exist 2 types of KS lesions: first, those with tightly restricted latent transcription, including LANA, K15, the viral IFN regulatory factors, and all viral miRNAs; and second, those with extended viral transcription, including RTA/ORF50, the viral IL-6 protein, and various early and late genes (52). This evidence concerns the gene KRT15 and Kaposi's sarcoma.