AZGP1 mRNA levels in normal human lung tissue correlate with lung cancer disease status.

Evidence in animal models has suggested an association between susceptibility to lung tumorigenesis and gene-expression profiles in normal lung. Here, we compared RNA pools from normal lung tissue of lung adenocarcinoma patients (cases) or non-lung cancer patients (controls) by hybridization of whole-human genome expression arrays. Principal component analysis identified a gene-expression signature of 85 genes that distinguishes cases from controls as well as smokers from nonsmokers. Elevated mRNA levels of one of these genes, AZGP1, were significantly associated with disease status. These results support the hypothesis that differences in the gene-expression levels of the normal tissue may be predictive of genetic predisposition to lung cancer in humans.