Sakamoto Kazuki, Sugimoto Yoshikazu, Miyadera Kazutaka, Oka Toshinori, Fukushima Masakazu
Optimal Medication Research Laboratory, Taiho Pharmaceutical Co., Ltd., 224-2 Hiraishi-Ebisuno, Tokushima 771-0194, Japan.
Int J Mol Med. 2005 Aug;16(2):245-9.
Orotate phosphoribosyltransferase (OPRT) is a key enzyme in the anabolism of 5-fluorouracil (5-FU), and its expression in tumors is thought to increase the efficacy of 5-FU against the tumor. To detect the OPRT protein by immunoblot and/or immunohistochemical methods, we prepared highly specific antibody to the peptides contained in the human OPRT amino acid sequence. The anti-OPRT polyclonal antibodies, obtained by immunizing rabbits with the OPRT peptides, had a high specificity for the OPRT protein in human tumor xenografts when it was analyzed by immunoblotting, and furthermore, there was a positive correlation between OPRT activity and protein content in 12 human tumors (R2 = 0.632). These results suggest that immunohistochemical detection of tumoral OPRT protein expression with our anti-OPRT antibodies may provide a useful method for predicting the clinical response to 5-FU-based chemotherapy.
乳清酸磷酸核糖基转移酶（OPRT）是5-氟尿嘧啶（5-FU）合成代谢中的关键酶，其在肿瘤中的表达被认为可提高5-FU对肿瘤的疗效。为了通过免疫印迹和/或免疫组织化学方法检测OPRT蛋白，我们制备了针对人OPRT氨基酸序列中所含肽段的高特异性抗体。用OPRT肽段免疫兔子获得的抗OPRT多克隆抗体，通过免疫印迹分析时，对人肿瘤异种移植中的OPRT蛋白具有高特异性，此外，在12例人类肿瘤中OPRT活性与蛋白含量之间存在正相关（R2 = 0.632）。这些结果表明，用我们的抗OPRT抗体免疫组织化学检测肿瘤OPRT蛋白表达可能为预测基于5-FU的化疗的临床反应提供一种有用的方法。
