The correlation of genetic instability of PINX1 gene to clinico-pathological features of gastric cancer in the Chinese population.

PURPOSE

This project explored the influence of loss of heterozygosity (LOH) and microsatellite instability (MSI) of locus D8S277 to PINX1 expression of gastric cancer in Chinese people.

METHODS

LOH and MSI of locus D8S277 in 90 paraffin-embedded gastric carcinoma specimens were detected by polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP). Envision immunohistochemistry was used to assess the expression of PINX1.

RESULTS

The frequency of LOH was higher in cases with lymph node metastasis than those without (18.57 vs. 0.00%, P < 0.01), and was higher in the specimens that were at TNM stage III + IV than those at stage I + II (21.43 vs. 2.94%, P < 0.01). In terms of the frequency of MSI, it was lower in cases with lymph node metastasis than those without (10.00 vs. 30.00%,P < 0.05). The positive rate of PINX1 protein was higher in samples without lymph node metastasis than those with lymph node metastasis (80.00 vs. 50.00%, P < 0.01); and was higher in the cases at TNM stage I + II than those at stage III + IV; and was lower in the cases between 40 and 60 years old than those above 60 years old (43.75 vs. 65.52%, P < 0.05).

CONCLUSION

LOH and MSI of PINX1 may play major role in tumor development and regulate it through different pathways. Because LOH plays a major role in negative expression of PINX1, it can be regarded as a sign of gastric cancer development and MSI may affect the prognosis and tumor turnover.