Research Article PTEN Plays an Important Role in Thrombin-Mediated Lung Cancer Cell Functions

which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Thrombin and itsmembrane receptor, protease-activated receptor 1 (PAR1), have been reported to promote the development of lung cancer in vitro and in vivo. However, the intracellular molecular mechanism or signaling pathway that mediates the cytological effects after the thrombin-receptor interaction is poorly understood. Our previous study observed that the expression of phos-phatase and tensin homolog deleted on chromosome 10 (PTEN) was downregulated in thrombin-stimulated lung cancer. In this study, the role of PTEN in thrombin-mediated cell function and the corresponding cell signaling pathway were studied in lung can-cer cell Glc-82.The results indicated that thrombin downregulates the PTEN expression level and that PTENplays an important role in thrombin-mediated Glc-82 functions, including cell cycle progression, cell apoptosis, and cell migration.The PI3K/AKT signal-ing pathway and its related proteins, including p27 and S phase kinase associated protein 2 (Skp2), are involved in the effects induced by PTEN downregulation. PAR1 plays a role in thrombin-mediated reduction of PTEN expression. This study suggested that the PTEN/PI3K/AKT signaling pathway plays an important role in thrombin/PAR1-mediated lung cancer cell growth and migration. 1