The Anti-Tumor Activities of Tumor Necrosis Factor Related Apoptosis Inducing Ligand (TRAIL) and Recombinant Fas Molecules in Breast Cancer Tumor Microenvironment

ABSTRACT Background: Breast cancer, the most common malignancy in women, is a major health problem that is characterized by a defect in cell death (apoptosis). TRAIL and Fas are members of TNF super family that can induce apoptosis and kill malignant cells as wells as bacterial and viral infected cells through activating both apoptotic extrinsic and intrinsic apoptotic pathways. As evasion of apoptosis is thought to be a mechanism of tumor escape, we aimed at the current study to investigate the apoptotic activities of TRAIL and recombinant Fas molecules in breast cancer tumor microenvironment. Methods: Brest tumor/normal tissue samples were collected from 30 radically mestectomized breast cancer patients and cultured individually in absence and presence of either TRAIL or rFas molecules. Apoptosis level was measured immune-histochemicaly according to caspase3 staining reaction. Results: Our results revealed that there is a significant increase in the level of induced apoptosis within the breast tumor tissue cultured with recombinant TRAIL molecules (TT ) than that induced in those cultured with recombinant Fas molecules (TF) or in absence of either (Mean ranks 2.8, 2.2 and 1.1 respectively, p<0.0001). No significant increase in induced apoptosis levels observed within the normal tissue culture systems N, NF and NT (mean rank 1.8,2 and 2.2 respectively, p = 0.396) while there was a significant higher levels of induced apoptosis observed in the treated tumor culture systems than that in corresponding normal ones (TF vs. NF and TT vs. NT, P