HIV-KS cells produce cytokines and angiogenic growth factors such as fibroblast growth factors (FGFs), tumour necrosis factor-α (TNF-α), interleukin-1 (IL-1), IL-6, Tat and oncostatin M. They express high affinity receptors for some cytokines [66,67]. This evidence concerns the gene TAT and Kaposi's sarcoma.