Correlation between AIDS-related Kaposi sarcoma histological grade and in vitro behavior: reduced exogenous growth factor requirements for isolates from high grade lesions.

Kaposi sarcoma, the most common AIDSassociatedmalignancy, affects 10-30% of allAIDS patients. To date, research into thebiological characteristics of AIDS-relatedKaposi sarcoma (AIDS-KS) derived cell lineshas been based on cultures established fromskin explants or pleural effusions/peritonealfluids. We have established several AIDS-KSlines from biopsy confirmed oral mucosal andepidermal AIDS-KS lesions and have found acorrelation between AIDS-KS lesional gradeand in vitro cellular growth characteristics. Incomparison to epidermal AIDS-KS lesions,mucosal AIDS-KS lesions frequently possessedboth a more advanced histologic grade anddemonstrated a greater capacity to proliferatein minimal medium. We report the ability ofAIDS-KS isolates from high grade lesions tosustain proliferation (greater than 60 populationdoubling levels) in medium not supplementedwith endothelial cell growth supplementand/or cytokine rich conditioned medium.These findings indicate that AIDS-KS cellsisolated from high grade lesions have reducedrequirements for exogenously provided growthsupplements, and suggest that increasedautologous cytokine production accompaniesAIDS-KS lesional progression.