BCL2 and Kaposi's sarcoma: Underlying causesUp regulation of Bcl-2 expression associated with reduced endothelial cell apoptosis.Bcl-2 favors the angiogenic process which is switched off in healthy tissuesDecreased expression of anti-apoptotic molecules occurs through the inhibition of endothelial cell adhesion onto the ECM or decreased expression of antigenic growth factors.The increase in Bcl-2 levels in late-stage KS lesions is accompanied with an increase in vascular cell apoptosis.