Differential gene expression patterns in lung carcinogenesis mediated by loss of mouse tumor supressor Gprc5a

Increasing the understanding of the impact of changes in oncogenes and tumor suppressor genes is essential for improving the management of lung cancer. Recently, we identified a new mouse lung-specific tumor suppressor - the G-protein coupled receptor 5A (Gprc5a). We sought to understand the molecular consequences of Gprc5a loss and towards this we performed microarray analysis of the transcriptomes of lung epithelial cells cultured from normal tracheas of Gprc5a knockout and wild-type mice to define a loss-of-Gprc5a gene signature. Moreover, we analyzed differential gene expression patterns between Gprc5a knockout normal lung epithelial cells as well as lung adenocarcinoma cells isolated and cultured from tumors of NNK-exposed Gprc5a knockout mice. Gprc5a wild type cells (WT-NLE) and Gprc5a knockout cells (NULL-NLE) were isolated and cultured from trachea of three week old Gprc5a wild type and knockout mice, respectively. MDA-F471 mouse lung adenocarcinoma cells were derived de novo from an adenocarcinoma that was found in the lung of a female Gprc5a-knockout mouse sacrificed 16 months after NNK tobacco carcinogen i.p. injection based on a protocol approved by the M.D. Anderson Cancer Center Institutional Animal Care and Use Committee. Following RNA extraction and purification, the transcriptome of the Gprc5a wild type and knockout cells were analyzed by microarray analysis using the Affymetrix MG-430 2.0 murine array platform.