Novel biomarker candidates for gastric cancer.

Gastric cancer continues to be a major threat to human health. Molecular descriptions on the diverse phases of this disease will be valuable for a better diagnosis and development of therapeutic targets. Previously, a 92-gene classifier that distinguishes tumor from non-tumor gastric tissues was proposed. To corroborate this finding, independent approaches of gene selection and class prediction algorithm were applied to the dataset of 86 tissues profiled on 17K cDNA microarrays. As a result, 22 genes were selected, of which 18 were in common with 92 genes previously shown. The differential expression patterns of Chromogranin A (CHGA) and Thy-1 cell surface antigen (THY1) were further validated with immunohistostaining on gastric tissue microarrays. The differential expression patterns of several of the proposed genes have been proven to be critical for tumor progression in other cancer models and will likely function as novel biomarkers for gastric cancer as well.