[Expression of PTEN and its correlation with angiogenesis in gastric carcinoma].

BACKGROUND/AIMS: Phosphatase and tensin homolog deleted on chromosome ten (PTEN) is a recently clarified tumor suppressor gene located in 10q23.3. Alterations of this gene are associated with tumor progression and unfavorable outcome in various human cancers. Recently, PTEN has a possible role in angiogenesis by modulating angiogenic factor including vascular endothelial growth factor (VEGF). The aim of this study was to investigate the roles of PTEN and VEGF status for angiogenesis in human gastric cancer.

METHODS

We conducted an immunohistochemical investigation of PTEN and VEGF expression in 90 cases of paraffin section obtained from gastric cancer patients undergone surgical treatment.

RESULTS

Negative expression of PTEN and positive expression of VEGF in gastric cancer tissues, were demonstrated in 40.0% and 77.8% of cases, respectively. However, no significant correlation was found between PTEN, VEGF expression and various clinicopathological parameters. PTEN expression did not correlate significantly with VEGF expression (p=0.301). High microvessel density (MVD) was significantly associated with lymph node metastasis and poor survival (p=0.014, 0.011, respectively). The mean MVD value of PTEN negative tumors was 90.4+/-43.0 and significantly higher than that of PTEN positive tumors (p=0.028). The mean MVD value of VEGF positive tumors was 86.4+/-6.7 and significantly higher than that of VEGF negative tumors (p=0.002). The mean MVD value of PTEN negative and VEGF positive tumors was 98.0+/-42.2, and significantly higher than those of the others.

CONCLUSIONS

These results suggest that loss of PTEN expression may play a critical role in tumor progression and metastasis by stimulating tumor angiogenesis in human gastric cancer.