mRNA expression of PTEN and VEGF genes in epithelial ovarian cancer

Objective: To investigate the mRNA expression of PTEN and vascular endothelial growth factor (VEGF) genes in ovarian cancer. Methods: We examined mRNA expression of PTEN and VEGF 165 in normal ovary (n=5), ovarian cyst (n=5), ovarian borderline tumor (n=9), epithelial ovarian cancer (n=60) and ovarian cancer cell line (CAOV-3) by RT-PCR. Their expressions were compared with clinicopathological features of ovarian cancer. The relationship between their expressions was concerned in all ovarian samples as well. Results: mRNA expression level of PTEN gene was significantly lower in ovarian borderline tumor or ovarian cancer than that in normal ovary or ovarian cyst( P <0.05). It was negatively correlated with clinicopathological staging( P <0.05), whereas positively with histological differentiation ( P <0.05). mRNA expression level of PTEN gene was significantly lower in ovarian endometrioid cancer than ovarian serous or mucinous cancer( P <0.05). mRNA expression level of VEGF 165 gene was significantly higher in ovarian cancer than that in normal ovary or ovarian cyst( P <0.05). It was positively correlated with clinicopathological staging( P <0.05), whereas negatively with histological differentiation ( P <0.05). mRNA expression level of VEGF 165 gene was significantly higher in ovarian serous cancer than in other ovarian epithelial cancers ( P <0.05). mRNA expression of VEGF 165 gene was inversely correlated with mRNA expression level of PTEN gene. Conclusion: Down-regulated expression of PTEN and up-regulated expression of VEGF were considered as two important events in tumorigenesis of ovarian cancer and could be used as molecular markers to indicate the pathobiological behaviors of ovarian cancer. Decreased PTEN expression and increased VEGF expression were closely associated with tumorigenesis and pathobiological behaviors of ovarian endometrioid and serous cancer respectively. Reduced expression of PTEN gene might be involved in carcinogenesis and progression of ovarian cancer by up-regulating the VEGF expression to enhance angiogenesis.