| Summary |
Kaposi's sarcoma-associated herpesvirus (KSHV) is the most recently discovered human herpesvirus. Kaposi's sarcoma-associated herpesvirus is etiologically associated with Kaposi's sarcoma (KS), multicentric Castleman disease (MCD), and primary effusion lymphoma (PEL). Kaposi's sarcoma development is dependent upon a myriad of growth factors (GFs) and inflammatory cytokines (IC) for proliferation, inflammation, and neoangiogenesis. Three independent studies demonstrated cigarette smoking to provide protection against KS. In these studies it was proposed that cigarette smoking provided protection against KS by altering the expression levels of GFs and ICs. Vascular endothelial growth factor (VEGF), one of the most important GFs, is elevated in KS lesions. VEGF not only mediates cancer development but also enhances KSHV infection. Hence, the VEGF levels in serum from non-smokers and cigarette smokers were analyzed. The serum from cigarette smokers showed significantly higher levels of VEGF than non-smokers. Despite the elevated serum levels of VEGF, the serum from cigarette smokers showed a significant inability to induce tubule formation, an indication of angiogenesis. These results demonstrate that the anti-angiogenic properties of serum obtained from smokers are independent of VEGF levels. Future studies will be directed towards identifying key players in the blood from cigarette smokers with anti-angiogenic properties. This type of analysis will prove to be useful in developing future anti-cancer drugs. |
