KRT1 and Kaposi's sarcoma: Immunohistochemistry staining for latent and lytic KSHV proteins as well as transcriptional profiling of KS tumours indicates that some tumours show a restricted pattern of viral gene expression, which is largely limited to the genes for LANA, the viral homologues of a D-type cyclin (vCYC), the viral FLICE inhibitory protein (vFLIP), and the viral micro-RNAs (miRNAs), in addition to K1, K15 and the viral G-protein-coupled receptor homologue (table 1), while in others additional viral genes belonging to the lytic (productive) replication cycle may be expressed [216–218].