KSHV non-structural membrane proteins involved in the activation of intracellular signaling pathways and the pathogenesis of Kaposi's sarcoma

Kaposi's sarcoma (KS) is an unusual neoplasm characterized by extensive neoangiogenesis, infiltrates of inflammatory cells and atypically differentiated spindle cells of endothelial origin. KS is caused by an oncogenic γ-herpesvirus, Kaposi's sarcoma-associated herpesvirus (KSHV)/human herpesvirus-8 (HHV-8). Several KSHV proteins can subvert multiple cellular angiogenic, mitogenic and inflammatory pathways. Here, we discuss the KSHV encoded membrane proteins vGPCR, K1 and K15, with a particular emphasis on their activation of cellular signaling pathways and their role in the development of specific features of KS.