Expression of PPAR-? in Lung Cancer and the Role of PPAR-? in Apoptosis of Lung Cancer

Abstract

Objective: To investigate the relationship between peroxisome proliferators-activated receptor-gamma (PPAR-γ) and clinical pathology of lung cancer, and to study the inhibitory effect of PPAR-γ activators on lung cancer growth and the mechanism of inducing apoptosis of lung cancer. Methods: Expression of PPAR-γ in 15 cases of non-cancerous lung tissues and 64 cases of lung cancer tissues was detected by using immunohistochemistry. The average A values were measured by using image analysis. The expression of PPAR-γ in lung cancer cells was detected by using RT-PCR. After being treated with PPAR-γ activators, apoptosis was detected by using flow cytometry, and meanwhile, the change in caspase-3 activity was detected by caspase-3 kits. Results: Expression levels of PPAR-γ in cancerous tissues were higher than those in non-cancerous lung tissues. In four types of lung cancer, the sequence of PPAR-γ expression from high to low levels was small-cell lung cancer, squamous carcinom, large-cell lung cancer, adenocarcinoma in turns. The expression of PPAR-γ was correlated with differentiation and postoperative TNM staging of lung cancer tissues, but not with lymph node metastasis. PPAR-γ expressed in two lung cancer cell lines, which could induce apoptosis of lung cancer cells after being treated with PPAR-γ activators, and caspase-3 activity in cells treated with PPAR-γ activators was significantly increased. Conclusion: PPAR-γ is correlated with clinical pathology and apoptosis of lung cancer closely, and activated PPAR-γ can increase caspase-3 activity to induce cells apoptosis. PPAR-γ will be able to become a new target for therapy of lung cancer in the future.