Loss of heterozygosity and microsatellite instabilities of fragile histidine triad gene in gastric carcinoma.

AIM

To detect the loss of heterozygosity (LOH) and microsatellite instabi1ities (MSI) of fragile histidine triad (FHIT) gene in gastric carcinoma and to study their association with the clinical pathological characteristics of gastric carcinoma.

METHODS

LOH and MSI of FHIT gene were detected at four microsaterllite loci D3Sl3H, D3S4l03, D3Sl48l and D3S1234 using PCR in matched normal and cancerous tissues from 50 patients with primary gastric cancer.

RESULTS

The average frequency of LOH and MSI of FHIT gene in gastric cancer was 32.4% and 26.4% respectively. LOH and MSI of FHIT gene in gastric cancer had no association with histological, Borrmann, and Lauren's classification. LOH of FHIT gene in gastric cancer was related to invasive depth. The frequency of FHIT LOH in gastric cancer with serosa-penetration was obviously higher than that in gastric cancer without serosa-penetration (73.5% vs 37.5%, P < 0.05). MSI of FHIT gene in gastric cancer was associated with the lymph node metastasis. The frequency of MSI in gastric cancer without lymph node metastasis was significantly higher than that in gastric cancer with lymph node metastasis (66.7% vs 34.3%, P < 0.05).

CONCLUSION

LOH of FHIT gene is correlated with invasive depth of gastric carcinoma. MSI of FHIT gene is correlated with lymph node metastases. LOH and MSI of FHIT gene play an important role in carcinogenesis of gastric cancer.