The expression of thymidine phosphorylase/platelet-derived endothelial cell growth factor is correlated to angiogenesis in breast cancer

It has been shown that human thymidine phosphorylase (TP) Is Identical to platelet-derlved endothelial cell growth factor and has angiogenlc actlvhy. In the present study, the expression of TP was examined In 139 mammary carclnomas and 35 benign mammary disorders using biochemical and lmmunohlstochemlcal methods. Moreover, In order to evaluate the significance of TP expression in mammary carcinomas, the relationship between vascular density and various cllnicopathological factors, including age and menopausal status of patients with a mammary carcinoma, were compared wtth the size, nodal status, expression of estrogen receptor (ER), progesterone receptor (PgR), c-erbB-2, p53 and TP of a mammary carcinoma. Thymidine phosphorylase expression Increased in both the nuclei and cytoplasm of mammary carclnoma cells in comparison to mammary benign disorder cells. The number of mlcroves-sels In mammary carcinomas was generally correlated to the number of tumor cells with TP expression in cytoplasm. The number of cells with TP expression in cytoplasm was significantly large In tumors that measured 34 cm In diameter, compared wtth tumors measuring 1–2 and 5–6 cm in diameter. In mammary tumors of 1–4 cm diameter, TP expression and vessel denslty were slgnlficantly high in tumors negative for ER or positive for cerbB2 and In tumors positive for TP or cerbB2, respectively; whereas tumors of 5–6 cm In diameter were not modified by any cllnlcopathological factors. The results lndlcated that TP plays an Important anglogenetic role In mammary carcinomas, especially tumors with a certain progression.