Correlation between gastric carcinoma and ZAC gene-associated microsatellite instability and loss of heterozygosity.

The present study explored the association between loss of heterozygosity (LOH) or microsatellite instability (MSI) of the zinc finger regulator of apoptosis and cell-cycle arrest (ZAC) gene and the clinicopathological factors of gastric cancer. Samples of cancer and cancer-adjacent normal tissue from 30 patients with gastric cancer were collected. The genomic DNA was extracted from each and amplified with primers specific to ZAC microsatellite mutations, then run on a polyacrylamide gel for analysis. The CA197 microsatellite locus exhibited LOH in cancer sample 4. There was LOH in the 15AAAG locus in cancer sample 27 and cancer-adjacent tissue 23, and MSI at 15AAAG in cancer-adjacent tissue 27. There was MSI at the D6S1703 microsatellite locus in cancer-adjacent tissue 28. There was no LOH or MSI in the CA340 microsatellite locus in the gastric cancer or adjacent tissues analyzed. Thus, the frequency of LOH or MSI at ZAC gene-associated microsatellite loci for all patients was 13.3% (4/30). The present study has demonstrated that LOH and MSI events may contribute to the downregulation of ZAC; however, it is unlikely to be the primary cause, as it was only identified in 13.3% of cases.