Camici M, Tozzi M G, Allegrini S, Del Corso A, Sanfilippo O, Daidone M G, De Marco C, Ipata P L
Istituto di Produzione Animale, Università di Udine, Pagnacco, Italy.
Cancer Biochem Biophys. 1990 Jul;11(3):201-9.
The enzymatic pattern of five enzymes involved in the purine salvage pathway, namely purine nucleoside phosphorylase (EC 2.4.2.1), adenosine deaminase (EC 3.5.4.4), 5'-nucleotidase (EC 3.1.3.5), alkaline phosphatase (EC 3.1.3.1), and hypoxanthine-guanine phosphoribosyltransferase (EC 2.4.2.8) has been evaluated both in human intestinal and breast carcinomas and compared to that of normal tissues. A higher level of hypoxanthine-guanine phosphoribosyltransferase was associated with tumor tissues. This metabolic alteration should lead to an elevated synthesis of nucleotides in cancer cells, might confer selective growth advantages to neoplastic tissues, and account, at least in part, for the difficulties encountered in the chemotherapy of human tumors, by using compounds affecting only the purine de novo biosynthesis.
嘌呤补救途径中涉及的五种酶，即嘌呤核苷磷酸化酶（EC 2.4.2.1）、腺苷脱氨酶（EC 3.5.4.4）、5'-核苷酸酶（EC 3.1.3.5）、碱性磷酸酶（EC 3.1.3.1）和次黄嘌呤-鸟嘌呤磷酸核糖转移酶（EC 2.4.2.8）的酶谱已在人肠道癌和乳腺癌中进行了评估，并与正常组织的酶谱进行了比较。肿瘤组织中次黄嘌呤-鸟嘌呤磷酸核糖转移酶水平较高。这种代谢改变应会导致癌细胞中核苷酸合成增加，可能赋予肿瘤组织选择性生长优势，并至少部分解释了在使用仅影响嘌呤从头生物合成的化合物进行人类肿瘤化疗时遇到的困难。
