Downregulation and CpG island hypermethylation of NES1/hK10 gene in the pathogenesis of human gastric cancer

The normal epithelial cell-specific-1 (NES1)/Kallikrein 10 gene is proposed to be a novel putative tumor suppressor gene in several malignant diseases. The role of NES1 gene in gastric cancer has not been fully understood. Our study revealed that CpG island hypermethylation plays an important role in the downregulation of NES1 mRNA expression in gastric cancer. In situ hybridization showed that loss or reduction of NES1 mRNA expression is associated with differentiation level during tumor progression suggesting that NES1 inactivation might contribute to the malignant progression of human gastric cancers.