Expression of peroxisome proliferator-activated receptor (PPAR)-gamma in human lung cancer

The peroxisome proliferator-activated receptor (PPAR)-gamma is a member of the steroid nuclear receptors. Recent studies have demonstrated that PPAR-g amma is expressed in several cancer cells. We examined the PPAR-gamma expre ssion in both normal lung and major types of human lung cancer. The express ion of PPAR-gamma mRNA was detected in 2 out of 3 normal lung tissues and i ts protein was detected in 3 out of 5 normal lung tissues. In contrast, a s mall cell carcinoma cell line and all other types of lung cancer tissues ex pressed PPAR-gamma mRNA and its protein. Immunoreactive PPAR-gamma is stron gly expressed in cancer cells and moderately in mononuclear cells, endothel ial cells and fibroblasts of lung cancer tissues. Our results suggest that PPAR-gamma may play an important role in the pathogenesis and/or progressio n of lung cancer, and may be a novel therapeutical target for therapy of lu ng cancer.