Constitutive NF-κB activation leads to transcriptional regulation of NF-κB target genes, including increased expression of proinflammatory cytokines (GM-CSF, IL-6 and IL-1β), chemokines (Mip1α, Rantes, Mcp-2, Ip-10 and I-tac) and interferon-responsive genes, which are likely critical contributors to the prominent proinflammatory phenotype of KS [19,57]. Here, IL6 is linked to Kaposi's sarcoma.