AIM: To study the expression level of gene SNC66 in gastric cancer tissues, and investigate the relationship between the expression of SNC66 and the pathogenesis of gastric cancer.METHODS: Paired normal and cancerous paraffin-embeded tissues from 20 gastric cancer patients were tested by in situ hybridization (ISH) and in situ reverse transcription and polymerase chain reaction (ISRT-PCR)using ?-actin as a control.RESULTS: ISH and ISRT-PCR both showed that SNC66 were all strong positive expressed in 20 normal gastric mucosa.But in 20 gastric cancer tissues,the ISH showed that 8 were negative,8 were weak positive and 4 were strong positive. The ISRT-PCR showed that 6 were negative,9 were weak positive and 5 were strong positive when the PCR cycled 10 times;4 were negative and 16 were strong positive when the PCR cycled 25 times. CONCLUSION: There was significant expression reduction or defect of SNC66 in gastric cancer tissues.SNC66 should be further investigated as a gastric cancer negative relative gene.

Objective To detect the expression status of new gene SNC73 in common epithelium cancer tissues and to elucidate the relationship between the expression of SNC73 and the genesis of tumors. Methods Paired tumor and normal tissues from five different types of human cancers were tested by cRNA/mRNA in situ hybridization using the digoxingen labeled probe. Results SNC73 was highly expressed in epithelium cells and lymphocytes of normal colorectal and gastric mucosa, and its expression was significantly lower or even deficient in colorectal and gastric cancer tissues. No expression could be detected both in the normal and cancer tissues of liver, lung or breast. Conclusions SNC73 is a novel gene related to the cancer of digestive tract, and should be further investigated as a candidate of the tumor suppressor gene.