Selective cyclooxygenase-2 inhibitors and non-small cell lung cancer.

Lung cancer is the leading cause of death from cancer in most developed nations. The most common type of lung cancer is of non-small cell histology, representing approximately 80% of the total. Despite aggressive treatments in early stages and improvement of polychemotherapy outcomes in advanced disease, the five years survival rate for lung cancer remains under 15%. Fortunately, our improved knowledge of tumor biology and mechanisms of oncogenesis suggests several new potential targets for clinical research in cancer therapy. A substantial body of evidence indicates that cyclooxigenase (COX)-2 and prostaglandins (PGs) play an important role in tumorigenesis. Mechanisms involved in COX-2 participation in tumorigenesis and tumor growth include xenobiotic metabolism, angiogenesis stimulation, inhibition of immune surveillance and inhibition of apoptosis. COX-2 is frequently overexpressed in bronchial premalignancy, lung adenocarcinoma and squamous cell carcinoma and COX-2 overexpression is a marker of poor prognosis in surgically resected stage I non-small cell lung cancer. Treatment with COX-2 inhibitors reduces the growth of NSCLC cells in vitro and in xenograft studies. Recent studies have defined some of the mechanisms involved in COX-2 participation in NSCLC development and diffusion. These evidences support the hypothesis that selective COX-2 inhibitors (coxibs) may prove beneficial in the prevention and treatment of NSCLC.