BCL2 and neoplasm: Toward examining the possibility that co-delivery of PTX Bcl-2 siRNA encapsulated liposomes may lead to apoptosis of the tumor endothelial cells, fixed tumor cryosections prepared from tumor bearing mice treated with PTX drug alone and Bcl-2 siRNA formulated liposomes were immunostained with tumor endothelial cell marker VE-cadherin and TUNEL following manufacturer’s protocol (Clontech Laboratories, Mountain View, CA, USA).