The Kaposis Sarcoma Associated Herpesvirus: A model for viral oncogenesis

Kaposis sarcoma (KS) is the most common tumor arising in HIV-infected patients and remains a significant cause of morbidity and mortality among the AIDS population in the developing world. The recent discovery of the etiologic agent of KS, the Kaposis sarcoma associated herpesvirus (KSHV), has invigorated new awareness of this unique neoplasm. Indeed, examination of the KSHV genome has revealed numerous genes that may contribute to the development of the spindle cell, the dominant cell in KS lesions. Here the authors survey the current knowledge on how KSHV-encoded genes play integral roles in transformation, cell survival, and neoangiogenesis through the transduction of signals from viral-encoded genes to the host cell nucleus. These signaling pathways likely affect the expression of cellular genes involved in KS pathogenesis. Since signaling pathways have proven to be successful drug targets in the past and their role in Kaposis sarcoma is becoming apparent, viral-encoded survival genes are emerging targets for the development of drug research. It is therefore of utmost importance to further define their involvement in KS pathogenesis.