Thymidine phosphorylase (E.C. 22.214.171.124) (TP), also described as the angiogenic platelet-derived endothelial cell growth factor (PD-ECGF) (1, 2, 3, 4), is a homodimeric enzyme with a monomeric molecular mass of about 55 kDa (5,6) that phosphorolytically cleaves thymidine to yield thymine and deoxyribose-1-phosphate (dR-1-P) (7,8). TP is expressed in various human cells and tissues and plays a role in plasma thymidine homeostasis (9, 10, 11). The levels of expression in different human tissues can vary up to 15-fold (12). Moreover, TP levels are increased in several types of malignant tumors when compared to the non-neoplastic regions of these tissues (13) and also in the plasma from tumor-bearing animals and cancer patients (14).
KeywordsThymidine Phosphorylase Bystander Effect Thymidine Phosphorylase Expression Thymidine Phosphorylase Activity Cloning Ring
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