Anti-HIV agent MAP30 modulates the expression profile of viral and cellular genes for proliferation and apoptosis in AIDS-related lymphoma cells infected with Kaposi's sarcoma-associated virus

The anti-HIV agent MAP30 (Momordica anti-HIV protein, 30 kDa) inhibits the proliferation of BC-2, an AIDS-related primary effusion lymphoma (PEL) cell line derived from an AIDS patient. BC-2 cells are latently infected with Kaposi's sarcoma-associated herpes virus (KSHV), also known as human herpes virus 8 (HHV8). We examined the effect of MAP30 on the expression of viral and cellular genes in BC-2 during latent and lytic states of the viral life cycle. By Northern analysis and RT-PCR, we found that MAP30 downregulates the expression of viral cyclin D (vCD), viral interleukin-6 (vIL-6), and viral FLIP (vFLIP), genes involved in cell cycle regulation, viral pathogenesis, and apoptosis. By pathway-specific cDNA microarray analysis, we found that BC-2 cells express high levels of egr-1, ATF-2, hsp27, hsp90, IkappaB, mdm2, skp1, and IL-2, cellular genes involved in mitogenesis, tumorigenesis, and inhibition of apoptosis in NFkappaB and p53 signaling pathways. These results define for the first time the specific cellular pathways involved in AIDS-related tumorigenesis and suggest specific novel targets for the treatment. Furthermore, we found that MAP30 downregulates the expression of egr-1, ATF-2, hsp27, hsp90, IkappaB, mdm2, and Skp1, while it upregulates the pro-apoptotic-related genes Bax, CRADD, and caspase-3. Thus, MAP30 modulates the expression of both viral and cellular genes involved in KS pathogenesis. These results provide valuable insight into the molecular mechanisms of MAP30 anti-KS action and suggest its utility as a therapeutic agent against AIDS-related tumors.