Fas and cancer

Apoptosis is an active process of programmed cell death. Fas is a cell-surface protein which is expressed on activated lymphocytes and known as CD95, TNFRSF6 or APO-1. Fas-L is ligand of Fas and known as CD95 LG or TNFSF6. Apoptosis or cell death is a result of binding of Fas-L to Fas which is expressed on the surfaces of these cells. Cancer cells escape this binding by overexpression of Fas-L or down expression of Fas. Fas and Fas-L exist in membrane bound and soluble forms. The serum level of sFas and sFas-L can be evaluated by immunostaining, immunohistochemical methods, immunofluorescence, flow cytometry and Western blotting. Head and neck squamous cell carcinoma diagnosis, staging and prognosis can be evaluated early and accurately by sFas and sFas-L expression levels detection.