氟尿嘧啶对胃肠道肿瘤细胞DPD和TP表达的影响

背景与目的：氟尿嘧啶（5-FU）足胃肠道肿瘤化疗的首选和基本用药，其分解代谢的限速酶——二氢嘧啶脱氢酶（DPD）和激活酶——胸苛磷酸化酶（TP）决定了肿瘤区域的药物浓度和作用，且与5-FU的化疗敏感性有一定相关性。本研究旨在观察胃肠道肿瘤细胞中，5-Fu对DPD和TP的表达有无调节作用。方法：选取胃癌细胞株SGC7901、大肠癌细胞株SW1116和人脐静脉内皮细胞ECV-304，用不同浓度的5-FL作用不同时间后，以RT-PCR，ELISA和免疫组化等方法分别榆测DPD和TP的mRNA和蛋白含量，观察药物作用对不同细胞代崩酶表达的影响。结果：5-FU作用于不同细胞后表现不同：其中SGC7901、SW1116两株肿瘤细胞的DPD蛋白水平均上调，且表现为时间依赖性；在上述两株细胞中，TP蛋白表达呈小剂量上调、大剂量下凋的双重效应，并随时间延长表达增加；5-FU作用后DPD和TP mRNA水平则无显著改变。ECV-304细胞株的DPD和TP mRNA与蛋白表达不受5-FU影响。结论：胃肠道肿瘤细胞内，DPD和TP表达在蛋白水平上受5-Fu调控，而正常细胞不受影响。     

TP和DPD在乳腺癌组织中的表达及其意义

背景与目的胸腺嘧啶磷酸化酶(TP)和双氢嘧啶脱氢酶(DPD)在乳腺癌组织中的表达对判断预后与治疗的选择有着积极意义,我们对TP和DPD在乳腺癌与癌旁正常组织中的表达进行了研究,以评估其潜在的临床意义。方法应用ELISA方法对20例乳腺癌患者癌组织和癌旁正常组织中TP和DPD的含量进行检测并行统计学分析。结果20例患者中,癌组织TP平均浓度为(136.47±13.97)ng/mg,DPD平均浓度为(31.23±19.37)ng/mg,癌旁正常组织TP平均浓度为(14.48±2.72)ng/mg,DPD平均浓度为(31.57±12.95)ng/mg,癌组织中TP浓度比正常组织高近10倍(P<0.01)。结论乳腺癌组织中TP的表达远高于癌旁正常组织,DPD的表达在癌组织和癌旁正常组织中无显著差异,癌组织中TP与DPD的比值远高于癌旁正常组织。     

结直肠癌组织中TP/DPD表达的研究

背景与目的:胃肠道肿瘤患者对氟尿嘧啶类药物的反应率存在很大个体差异,原因在于肿瘤内氟尿嘧啶类药物代谢酶[1,2],胸苷磷酸化酶(TP)和二氢嘧啶脱氢酶(DPD)水平的差异;本文探讨TP和DPD在大肠癌的表达和定位。方法:21对正常大肠粘膜及大肠癌手术切除标本,采用ELISA、免疫组织化学检测与临床病理指标相结合。结果:21对结直肠癌标本中,肿瘤组织与正常大肠粘膜的平均TP含量分别为(60.25±36.18)U/mg和(22.37±13.69)U/mg(P<0.01)。肿瘤与正常大肠粘膜内平均DPD分别为(12.75±5.86)U/mg和(14.02±7.48)U/mg。免疫组织化学染色显示,TP与DPD既可出现在肿瘤细胞内,也广泛存在于癌周免疫反应及炎细胞内。TP、DPD表达与Dukes分期等临床病理指标无明显关系。结论:正常大肠粘膜及癌组织中TP与DPD含量的个体间差异是临床氟尿嘧啶类药物有效性及毒副反应差别的理论依据。检测TP表达可用于5-FU前体药物敏感性的预测,检测DPD表达可作为氟尿嘧啶类药物敏感性预测指标。     

二氢嘧啶脱氢酶（DPD）与胸苷酸合成酶（TS）在结直肠癌中的表达及预后价值

目的：探讨5-FU代谢酶在结直肠癌中的表达及其与预后的关系。方法：44例结直肠癌根治术后分别施以5-FU为主的辅助化疗,并通过免疫组化检测二氢嘧啶脱氢酶（DPD）和胸苷酸合成酶（TS）的表达。结果：DPD阳性表达的结直肠癌无病生存期显著缩短（P=0．047）,而总生存期也有缩短的趋势,但差异无显著意义（P=0．136）。而偈表达与预后无关（P〉0．05）,但TS在晚期肿瘤中表达较高（P〈0．05）。结论：在接受5-FU为主辅助化疗的结直肠癌患者中,DPD表达可作为预后的重要指标。TS表达与临床分期密切相关,可视为结直肠癌进展的生物学标志。     

二氢嘧啶脱氢酶(DPD)与胸苷酸合成酶(TS)在结直肠癌中的表达及预后价值

目的:探讨5-FU代谢酶在结直肠癌中的表达及其与预后的关系.方法:44例结直肠癌根治术后分别施以5-FU为主的辅助化疗,并通过免疫组化检测二氢嘧啶脱氢酶(DPD)和胸苷酸合成酶(TS)的表达.结果:DPD阳性表达的结直肠癌无病生存期显著缩短(P=0.047),而总生存期也有缩短的趋势,但差异无显著意义(P=0.136).而TS表达与预后无关(P＞0.05),但TS在晚期肿瘤中表达较高(P＜0.05).结论:在接受5-FU为主辅助化疗的结直肠癌患者中,DPD表达可作为预后的重要指标.TS表达与临床分期密切相关,可视为结直肠癌进展的生物学标志.     

胃癌组织中胸腺嘧啶合成酶和双氢嘧啶脱氢酶的表达及临床意义

目的 了解胸腺嘧啶合成酶(TS)和双氢嘧啶脱氢酶(DPD)mRNA在胃癌组织及癌旁非肿瘤组织中的表达情况以及与临床病理学特征的关系.方法 采用半定量反转录聚合酶链式反应(RT-PCR)方法测定50例胃癌患者TS、DPD mRNA在胃癌及癌旁非肿瘤组织的表达.结果 胃癌组织中TS mRNA水平明显高于非肿瘤组织中的水平(...     

胸苷磷酸化酶在肿瘤组织中的表达及其临床应用

胸苷磷酸化酶（TP）参与嘧啶核苷合成和分解的过程,作为一种血管生成因子,在肿瘤的生长、浸润和转移过程中有重要的作用,也在5-Fu等药物的代谢中起作用.现综述TP可能的促癌机制、TP在肿瘤组织中的表达及与临床病理因素的关系、TP的临床应用价值.     

延边地区胃癌中TP和COX-2表达及其临床意义

[目的]探讨TP和COX-2在胃癌中的表达及其临床意义。[方法]采用免疫组化方法检测TP和COX-2在50例胃癌中的表达,分析其与胃癌临床病理特征及预后的关系。[结果]TP和COX-2在胃癌中的阳性表达率分别为56.0%（28/50）和62.0%（31/50）。TP蛋白表达与胃癌的分化程度、浸润深度和淋巴结转移相关（P〈0.05）;COX-2蛋白表达与胃癌淋巴结转移相关（P〈0.05）。胃癌组织中TP和COX-2的表达呈正相关（χ^2=4.565,P〈0.05）。TP表达阳性和阴性者的5年生存率分别为25.0%和54.5%（P〈0.05）;COX-2表达阳性和阴性者的5年生存率分别为22.6%和63.2%（P〈0.05）。[结论 ]TP和COX-2在胃癌的发生发展中可能起重要作用,可作为预测胃癌预后的指标。     

胃癌患者血清DPD mRNA和TS mRNA表达对替吉奥疗效预测价值分析

目的 探讨进展期胃癌(advanced gastric carcinoma,AGC)患者二氢嘧啶脱氢酶(thymidine phosphorylase,DPD) mRNA和胸苷酸合成酶(thymidylate synthase,TS) mRNA表达与含替吉奥(S-1)方案化疗疗效的关系.方法 收集2012-09-01-2013-09-01苏州市相城人民医院收治经病理确诊的AGC患者40例,化疗前抽取外周血采用RT-PCR法检测DPD mRNA及TS mRNA表达水平,给予含S-1的方案:S-1(40 mg/m2,2次/d,口服14 d)+顺铂(DDP,75 mg/m2,静脉滴入,d1)化疗.分析DPD mRNA及TS mRNA表达与化疗疗效的关系.结果 RT-PCR检测结果显示,40例患者的DPD mRNA和TS mRNA表达相对于β-actin的相对数值分别为2.53±1.86和0.636±0.363.DPDmRNA和TS mRNA表达水平之间有显著相关性,r=0.68,P＜0.01.AGC患者外周血中DPD mRNA表达与Lauren分型显著相关,x2 =3.259,P=0.032.TS mRNA表达则与是否有远处转移显著相关,x2 =3.294,P=0.040. DPDmR-NA及TS mRNA均是表达越高患者疗效越差,表达越低患者疗效越好,r=0.708,P＜0.01;r=0.728,P＜0.01.联合分析显示,DPD mRNA及TS mRNA同时低表达时疗效更好,x2 =13.23,P=0.004.结论 DPD mRNA及TS mRNA表达可单独或联合用于预测AGC患者对含S-1方案的化疗疗效,初步研究结果提示可以根据患者外周血DPD mRNA及TS mRNA表达来指导胃癌的个体化治疗.     

胸苷磷酸化酶在肿瘤组织中的表达及其临床应用

胸苷磷酸化酶(TP)参与嘧啶核苷合成和分解的过程,作为一种血管生成因子,在肿瘤的生长、浸润和转移过程中有重要的作用,也在5-Fu等药物的代谢中起作用.现综述TP可能的促癌机制、TP在肿瘤组织中的表达及与临床病理因素的关系、TP的临床应用价值.     

Expression of Thymidine Phosphorylase in Human Gastric Carcinoma

The activity of thymidine phosphorylase (dThdPase) has heen reported to increase in several types of malignant tumors. Experimental evidence has shown that dThdPase is identical to platelet-derived endothelial cell growth factor, and that dThdPase has angiogenic activity. We examined the expression of dThdPase to investigate whether the expression of dThdPase correlates with angiogenesis, clinicopathologic features and the prognosis of patients with human gastric carcinomas. Microvessels were assessed by immnnostaining endothelial cells for factor VIII. We counted microvessels in the tumors of 158 patients whose tumors were completely removed surgically. Microvessels were counted in a × 400 field in the most active areas of neovascularization. We purified a monoclonal antibody (TMA-1) against dThdPase and studied the expression of dThdPase using TMA-1 in the same serial sections as those used for the detection of factor VIII. The correlation between angiogenesis and dThdPase, and the clinicopathological significance of dThdPase, in patients with gastric carcinoma were examined. The positive expression of dThdPase was more frequent (P<0.001) in gastric carcinomas (67/158, 43.4%) than that in normal tissues (12/158, 7.6%). The average microvessel count in dThdPase-positive gastric carcinomas was higher (P<0.001) than that in dThdPase-negative carcinomas. The percentage of gastric carcinoma cells expressing dThdPase was significantly correlated with the microvessel count (P<0.001). Further, the average size of dThdPase-positive carcinomas was significantly larger (P<0.001) than that of negative carcinomas and the mean microvessel count in dThdPase-positive gastric carcinomas was also significantly higher (P<0.001) than that in dThdPase-negative carcinomas. There was a significant correlation between the positive expression of dThdPase and microvessel count (P<0.001) or lymph node metastasis (P=0.013) by multivariate logistic analysis. Further, patients with dThdPase-positive carcinoma showed a significantly worse prognosis than those with dThdPase-negative carcinoma overall and in stage III. These findings indicate that the expression of dThdPase in gastric carcinomas is related to progression and metastasis, and this enzyme affects the prognosis of some patients with the disease.     

Regulation of Dihydropyrimidine Dehydrogenase and Pyrimidine Nucleoside Phosphorylase Activities by Growth Factors and Subsequent Effects on 5-Fluorouracil Sensitivity in Tumor Cells

Dihydropyrimidine dehydrogenase (DPD) and pyrimidine nucleoside phosphorylase (PyNPase) are the first and rate-limiting enzymes that regulate 5-fluorouracil (5-FU) metabolism, and tumoral DPD activity appears to be a promising predictor of 5-FU sensitivity. However, the regulatory mechanisms determining these enzyme activities have not been fully understood. We investigated the biological effects of epidermal growth factor (EGF) and transforming growth factor (TGF)α on cell growth and tumoral DPD and PyNPase activities, and the subsequent effects on 5-FU sensitivity in uterine cervical carcinoma SKG-IIIb cells. The treatment of tumor cells with EGF or TGF-α resulted in a concentration-dependent increase in tumor cell growth and PyNPase activity, whereas tumoral DPD activity was inhibited. Their stimulatory effects on tumor cell growth correlated well with PyNPase activity, but were inversely related to DPD activity ( P <0.01). 5-FU sensitivity of tumor cells increased in the presence of EGF or TGF-α. These growth factors were shown to stimulate the first, rate-limiting enzyme activity in 5-FU anabolism and to inhibit that in 5-FU catabolism, leading to enhancement of the antiproliferative action of 5-FU at achievable therapeutic levels. The tumor environmental factors, EGF and TGF-α, may act as intrinsic regulators of DPD and PyNPase activities that affect the 5-FU sensitivity of individual tumors.     

Expression of Thymidine Phosphorylase in Primary Human Renal Cell Carcinoma by ELISA Method

Thymidine phosphorylase (TP) expression in 100 paired samples of renal cell carcinoma (RCC) and normal adjacent tissue was analyzed by an ELISA method. We also investigated whether TP expression correlates with clinicopathological findings and clinical outcomes of these patients. Median TP expression was 9-fold (range, 0.5–56) higher in primary tumor than in non-cancerous renal tissue (P<0.0001). There was a significant difference with respect to tumor venous invasion. TP expression was significantly higher in patients with such venous invasion than in those without (P=0.018). However, there was no correlation between TP level and other clinicopathological findings and the survival curves. These results suggest that ELISA is useful for evaluating TP expression of human RCC and may provide a novel approach to therapy for patients with RCC.     

胸苷磷酸化酶与肿瘤发生发展关系的研究进展

胸苷磷酸化酶是一种血管生长因子,与肿瘤血管生长密切相关.近年来,在促进肿瘤生长、预测肿瘤患者生存期及化疗效果方面的作用日益受到关注.胸苷磷酸化酶通过增加肿瘤基质中的微血管密度,促进肿瘤生长和转移.患者的肿瘤切除标本中胸苷磷酸化酶的表达程度与患者的肿瘤复发率、转移率呈正相关,与生存率呈反相关.希罗达的广泛使用证实胸苷磷酸化酶能增加5-氟脲嘧啶类化疗药物的抗肿瘤疗效.本文就这些方面的研究进展做一综述.     

Thymidine phosphorylase expression is preserved after radiotherapy in patients with cervical squamous cell carcinoma

Purpose The aim of this study was to investigate the changes in two of the enzymes involved in fluorouracil metabolism, thymidine phosphorylase (TP) and dihydropyrimidine dehydrogenase (DPD), in uterine cervical squamous cell cancer tissue after radiotherapy.Subjects and methods Cervical tissue from 27 patients diagnosed with stage IIIB or IV uterine cervical squamous cell cancer was compared with normal cervical tissue from 33 patients with benign gynecologic diseases. Expression of TP and DPD in the cervical tissues was measured using enzyme-linked immunosorbent assays. TP and DPD expression before and after irradiation with 10 and 20 Gy was measured in 9 of the 27 patients with cervical cancer.Results Before irradiation, DPD expression in cancer tissue did not differ from that in normal tissue. TP expression and the TP/DPD ratio were significantly higher in cancer tissue than in normal tissue (P<0.00001). TP and DPD expression and the TP/DPD ratio were not significantly changed by irradiation with 10 and 20 Gy. TP expression and the TP/DPD ratio after irradiation with 10 and 20 Gy were significantly higher than in normal tissue.Conclusion The increased TP expression and the elevated TP/DPD ratio following irradiation with up to 20 Gy may offer an increased clinical advantage to chemoradiotherapy with capecitabine or doxyfluridine over radiotherapy alone.     

Dihydropyrimidine dehydrogenase and thymidylate synthase activities in hepatocellular carcinomas and in diseased livers

Background/purpose Dihydropyrimidine dehydrogenase (DPD) and thymidylate synthase (TS) are key enzymes for predicting the efficacy of 5-FU in the treatment of malignant tumors. However, 5-FU is not commonly commonly chosen for chemotherapeutic treatment of hepatocellular carcinoma (HCC) in practice. The aim of this study was to determine the activities of both DPD and TS in HCCs and corresponding liver parenchyma and to assess the correlation between the activities of these enzymes and clinicopathological features. The possibility of using 5-FU as a first-choice chemotherapeutic agent for HCC was also evaluated.Methods The study material comprised 33 pairs of hepatocellular carcinoma and noncancerous liver samples. The DPD and TS activities were quantified by a radiometric enzymatic assay and a 5-fluoro-2-deoxyuridine-5- monophosphate (FdUMP) ligand-binding assay, respectively.Results Pathologically invasive HCCs tended to show higher DPD activity and lower TS activity with some exceptions. DPD activity was lower in the HCCs regardless of their clinical features than in the noncancerous liver parenchyma, whereas TS activity was generally lower in HCCs except for those with certain clinical features. HCCs with multiple nodules showed lower DPD activity and those with a diameter of more than 5 cm showed lower TS activity. In the noncancerous liver parenchyma, a gradual decrease in DPD activity and an increase in TS activity were associated with the age of the patient, liver damage and z-factor. Of 30 HCC samples, 10 exhibited comparatively low DPD and TS activity, and these could be considered 5-FU-sensitive HCC.Conclusions DPD and TS activity may be affected by the clinicopathological status in both the HCC and the corresponding liver parenchyma. However, further investigation is necessary. Some HCC patients may be good candidates for 5-FU-based chemotherapy based on measurements of tumor levels of DPD and TS.     

High Expression of Thymidylate Synthase Leads to Resistance to 5-Fluorouracil in Biliary Tract Carcinoma in vitro

To evaluate the effect of chemotherapy of 5-fluorouracil (5-FU) in human biliary tract carcinoma, we studied 5-FU sensitivity, thymidylate synthase (TS) content, and dihydropyrimidine dehydroge-nase (DPD) activity in 4 human biliary tract carcinoma cell lines compared to 12 various digestive carcinoma cell lines of human organs in vitro. 5-FU sensitivity in the cell lines was analyzed by MTT assay. TS content was analyzed by the [6-³H]FdUMP binding assay method, and DPD activity was analyzed by thin-layer chromatography (TLC). 5-FU lC₅₀ values of biliary tract carcinoma cell lines were significantly higher than those of the carcinoma cell lines of the other digestive organs: 97, 45, 119, and 194 tunes the concentration of the other digestive, pancreas, colon, and gastric carcinoma cell lines, respectively. TS content of biliary tract carcinoma cell lines was also significantly greater than that of the carcinoma cell lines of the other organs. No difference in DPD activity, however, was recognized between the carcinoma cell lines of each organ. TS content in the cell lines significantly correlated with 5-FU sensitivity, but DPD activity did not. Therefore, in the present study, TS expression was concluded to influence the high resistance to 5-FU of biliary tract carcinoma in comparison with the carcinomas of the other digestive organs.