Angiogenesis,Kaposi’s Sarcoma and Kaposi’s Sarcoma-associated Herpesvirus

Tumor angiogenesis is the uncontrolled growth of blood vessels in tumors,serving to supply nutrients and oxygen,and remove metabolic wastes. Kaposi’s sarcoma (KS),a multifocal angioproliferative disorder characterized by spindle cell proliferation,neo-angiogenesis,inflammation,and edema,is associated with infection by Kaposi’s sarcoma-associated herpesvirus (KSHV). Recent studies indicate that KSHV infection directly promotes angiogenesis and inflammation through an autocrine and paracrine mechanism by inducing pro-angiogenic and pro-inflammatory cytokines. Many of these cytokines are also expressed in KS lesions,implicating a direct role of KSHV in the pathogenesis of this malignancy. Several KSHV genes are involved in KSHV-induced angiogenesis. These studies have provided insights into the pathogenesis of KS,and identified potential therapeutic targets for this malignancy.