The cytosol activity of thymidine phosphorylase in endometrial cancer

BACKGROUND: Thymidine phosphorylase (TP) is identical with platelet-derived endothelial cell growth factor (PD-ECGF) which promotes angiogenesis. The aim of this study was to evaluate the cytosol activity of TP in tumor samples from patients with endometrial cancer. METHODS: The activity of TP was measured by the spectrophotometric method in the cytosol of endometrial tumor samples from 43 patients. Moreover, the expression of platelet-derived endothelial cell growth factor/thymidine phosphorylase (PD-ECGF/TP) protein and microvessel density (MD) were examined in the same endometrial tumor samples by immunohistochemical staining. Normal endometrium from 16 women, treated surgically due to nononcological reasons served as a control. A relationship between the cytosol TP activity, PD-ECGF/TP protein expression, MD and clinicopathologic features was investigated. RESULTS: A significantly higher the cytosol TP activity, PD-ECGF/TP protein expression and MD was stated in malignant tumor samples when compared to the control (samples of normal endometrium). A positive statistically significant correlation between the cytosol enzyme activity and PD-ECGF/TP protein expression and MD was found, but weaker from the remaining ones between PD-ECGF/TP protein expression and MD was observed. Besides no correlation between the cytosol TP activity, PD-ECGF/TP protein expression as well as MD and grading or histopatological type of endometrial cancer was stated. CONCLUSION: The cytosol TP activity in endometrial cancer is significantly higher than in normal endometrium, with no relation as to the stage and grade of tumors, but correlates with the PD-ECGF/TP protein expression and MD may therefore be associated with favorable prognosis in patients treated with chemo- or radiotherapy after surgery.