Assessment of Soluble Fas in Patients with Chronic Myeloid Leukemia


Background: Soluble Fas was produced from the cell surface of malignant cells in a form lacking the 21 amino acidresidues containing the transmembrane domain by alternative splicing. Trimerization of Fas receptor can beinhibited by soluble Fas (sFas) that act as decoys, binding FasL and preventing association with transmembraneFas. So it is supposed to act as a FasL inhibitor to bind Fas and prevent Fas-mediated apoptosis.Objective: to evaluate serum soluble Fas (sFas) level in patients with chronic myeloid leukemiaMaterials and Method: Serum levels of sFas were measured by ELISA method after venous blood was collected from56 CML patients (newly diagnosed and optimally treated) and 28 healthy subjects as control group. Absorbancewas read at a wave length of 450nm using ELISA reader. Soluble Fas level was then calculated by plotting theoptical density (O.D.) of each sample against the concentration in the standard curve.Results: There were no significant increases in serum sFas patient compared to healthy control with P=0.09. When themean sFas concentration was obviously highest in newly diagnosed (1163.6pg/ml) followed by optimally treated(1021.7 pg/ml) and lowest in healthy control (970.1pg/ml).Conclusion: Production of sFas in tumor patients may be a key mechanism to inhibit Fas-mediated apoptosis. Theidentification of sFas levels as a predictor of outcome in malignant disease further establishes a connectionbetween Fas loss-of-function and tumor progression