PTGS2 and infection: Significant detection of COX-2 in KS lesions (Figure 1A, B and C), long term KSHV infected endothelial cells (Figure 2) and in de novo infection of endothelial and fibroblast cells [26], as well as modulation of viral gene expression by COX inhibition (Figures 1 and 2), strongly indicated a role for COX-2/PGE2 in KSHV pathogenesis.