Viruses in the pathogenesis of Kaposi's sarcoma--a review.

Kaposi's sarcoma (KS) is the most frequent malignancy in AIDS patients. Epidemiological studies indicate that a sexually transmitted infections agent other than HIV is involved in the evolution of KS. This "KS agent" may induce a cascade of cytokines which promote the development of the tumor in an autocrine and paracrine mechanism. In this review article several viruses, especially the recently discovered Kaposi's sarcoma herpesvirus (KSHV or HHV-8), are discussed as possible KS agents, and different scenarios of the viral contribution to the pathogenesis of AIDS-associated KS are presented.