The evaluation of soluble Fas and soluble Fas ligand levels of bronchoalveolar lavage fluid in lung cancer patients

Fas-Fas Ligand (FasL) is one of the major mediator system that activates programmed cell death. Cleavage of membranebound FasL by a metalloproteinase-like enzyme resulted in the formation of soluble FasL (sFasL). sFasL as well as the transmembrane form of FasL binds to Fas and transduces apoptotic signal in Fas-expressing cells. It's suggested that soluble Fas (sFas) and sFasL has an impact on tumor progress and immune escape feature of tumor cells from the host immune system. Since Fas antigen expression in the lungs has been localized to alveolar and bronchial epithelial cells, in this study we aimed to investigate the sFas (pg/mL) and sFasL levels (pg/mL) of bronchoalveolar lavage (BAL) fluid in lung cancer patients. Study population was consisted of 27 patients with lung cancer (mean age 62.9 +/- 10.7 years, 25 control subjects (mean age 47.9 +/- 13.9 years). BAL was performed under local anesthesia, on the unaffected lung of patients; either subsegments of right middle or lingula. BAL sFas and sFasL were evaluated by using ELISA method. The mean levels of sFas was 60.8 +/- 56.8 in lung cancer patient and 39.5 +/- 25.9 in control subjects (p> 0.05). The mean levels of sFasL was 51.6 +/- 39.2 in cancer patient and 41.2 +/- 27.4 in control subjects (p> 0.05). In conclusion, although we did not observe any significant difference between two groups, higher BAL levels of sFas and sFasL levels in lung cancer patients than control subjects, made us thought that apoptosis might have a role development and progression of lung cancer.