Pathogenesis of oral Kaposi's Sarcoma in HIV-infection: relevance of endogenous glucocorticoid excess in blood and saliva.

Endogenous glucocorticoid excess with concomitant hypercortisolaemia and increased saliva levels of the free active hormone, is a common feature of HIV-infected/AIDS patients. Exposure of the oral tissues to virtually uninterrupted high burden of glucocorticoids through saliva may contribute to the high frequency of oral Kaposi's sarcoma (KS) in these patients. AIDS-KS cells contain unusually high levels of glucocorticoid receptor protein and recent studies indicate that growth of these cells in culture is significantly stimulated by glucocorticoids, particularly in the presence of growth factors, such as oncostatin-M. The suggestion that glucocorticoid excess may be important in the pathogenesis of KS in AIDS is not in conflict with the suspected aetiological role of newly reported KS-associated herpesviruses (KSHV), since steroid hormones may upregulate the expression of the viral gene. The latter is consistent with the observation that infection by specific oncogenic viruses does not necessarily result in cancers in the human, and does require the presence of other cellular factors or events.