Expression of PARP in lung cancer: Patients with COPD and mice

Lung cancer (LC) is a leading cause of cancer death worldwide. COPD is an independent risk factor for LC. Poly-ADP ribose polymerase (PARP)-1 and PARP-2 play crucial roles in DNA repair and cancer. Hypothesis: Expression of PARP-1 and PARP-2 may differ in tumors of LC patients with/without COPD and in mice (compared to non-tumor lungs) with experimental adenocarcinoma. Patients: Lung tumor and non-tumor specimens (thoracotomy) were obtained from LC patients with/ without COPD (two patient groups, N=9/group). Mice: Lung tumors (LP07 adenocarcinoma cells, 1 month) were harvested from lungs of wild-type BALB/C mice and non-tumor control mice were also studied (N=9/group). PARP-1 and PARP-2 expressions were determined in lung tumors and non-tumor samples from both human and mouse studies (immunoblotting). Patients: No significant differences were seen in PARP-1 protein levels between tumor and non-tumor samples in either LC or LC-COPD patients. However, a significant decline in PARP-2 protein levels were detected in tumors of both LC and LC-COPD patients, especially in the latter group, compared to non-tumor lung samples. Mice: whereas PARP-1 expression was significantly lower in mouse tumors than in non-tumor specimens, PARP-2 did not significantly differ between lung tumor and non-tumor control samples. There was a differential expression profile of PARP-1 and PARP-2 isoforms in lung tumors of the patients. In mice, PARP-1 and PARP-2 were also differentially regulated in lung t...
Source: European Respiratory Journal - Category: Respiratory Medicine Authors: Tags: Lung cancer Source Type: research