Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To evaluate the antitumor efficacy against metastatic breast cancer of fluoropyrimidines alone and combined with other chemotherapeutic agents, we developed a murine model of breast cancer metastatic to the lung by orthotopically implanting MDA-MB-435S breast tumors into mice. MDA tumor cells greatly metastasized to lung tissue only after the orthotopically implanted tumors were surgically removed. Measurement of the expression of enzymes involved in 5-FU metabolism showed significantly higher activity of dihydropyrimidine dehydrogenase (DPD) and lower activity of thymidylate synthase (TS) in the MDA metastases than in the orthotopically implanted tumors. Based on the enzymatic properties of metastatic tumors, the minimum toxic doses of UFT (17.5 mg/kg/day) as a DPD-inhibitory fluoropyrimidine (DIF), and of 5'-DFUR (120 mg/kg/day) as a non-DIF, were orally administered to mice with pulmonary metastasis of the breast tumor. The results showed that UFT significantly inhibited the growth of pulmonary metastases of the breast tumors, but 5'-DFUR did not. UFT seemed to inhibit the growth of the pulmonary metastases of the breast tumors in combination with paclitaxel (50 mg/kg) more than in combination with 5'-DFUR, although the antitumor efficacy of neither combination was significantly different from that of paclitaxel alone. These results suggest that combination of DIF with other chemotherapeutic drugs, such as taxanes, is required to attain high antimetastatic and antitumor efficacy against breast tumor metastases, based on the molecular characteristics of the metastatic tumors.
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PMID:[Antimetastatic and antitumor effects of fluoropyrimidines alone and combined with taxanes in a murine model of breast cancer metastatic to the lung]. 1181 85

Thymidine phosphorylase (TP) and dihydropyrimidine dehydrogenase (DPD) levels in transitional cell carcinoma of the bladder resected from 38 patients were examined by ELISA. TP levels in high-grade and invasive cancer were significantly higher than those in low-grade and superficial cancer, respectively. No significant differences in the DPD levels were observed among grades and stages, but the DPD/TP ratio was significantly lower in grade 3 tumor than in grade 1. These results demonstrated that 5'-deoxy-5-fluorouridine seemed to be useful for managing patients with grade 3 cancer. The present study also suggested that we might be able to exclude cases of bladder cancer in which 5-fluorouracil group medicines would be inappropriate candidates in treatment options by measuring both TP and DPD levels in the tumor.
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PMID:Thymidine phosphorylase and dihydropyrimidine dehydrogenase in bladder cancer. 1183 4

The rate-limiting enzyme to catabolize 5-fluorouracil (5-FU) is dihydropyrimidine dehydrogenase (DPD), which expression in cancerous tissue is reported to have a relation with anti-tumor effect for 5-FU. In this study, we evaluated the immunohistochemical expression in gastric cancer using two different kinds of anti-human DPD antibody, KM1915 and KM1919. However, recognition of both antibody was mimetic in human gastric cancer, and strong expression of DPD was observed in the interstitial tissue when using KM1919. There is a positive relationship between immunohistochemical expression by KM1915 and mRNA expression in human gastric cancer. Immunohistochemical study with KM1915 might be a clinically useful method to evaluate the expression of DPD in paraffin-embedded materials.
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PMID:[Dihydropyrimidine dehydrogenase expression in gastric cancer using anti-human dihydropyrimidine dehydrogenase monoclonal antibody]. 1186 31

We measured the activity of orotate phosphoribosyl transferase (OPRT), the amount of thymidylate synthase (TS) enzyme, and the activity of dihydropyrimidine dehydrogenase (DPD) for individual tissue types in order to study the contribution of these substances to the effects of the pyrimidine fluoride anticancer drug 5-fluorouracil (5-FU). We also studied the correlation between these 3 enzymes and clinical pathophysiologic characteristics (age, sex, extent of tumor invasion, extent of metastasis to the lymph nodes, lymphatic invasion and the venous invasion of the colorectal wall). Sixty-eight patients with colorectal carcinoma who had undergone surgical resection in our department were studied. There was a significant (p < 0.01) elevation of OPRT activity in the tumor tissue compared with regions of normal tissue. OPRT activity levels in the tumor tissue were lowest in patients with mucinous carcinoma while TS enzyme levels showed the highest activity in tumor tissue in poorly differentiated adenocarcinoma. DPD also showed high activity levels in tumor tissue in poorly differentiated adenocarcinoma and mucinous carcinoma. It is possible that the expression of enzymes with respect to the antitumor effects of 5-FU is a factor contributing to the poor prognosis for patients with poorly differentiated adenocarcinoma and mucinous carcinoma. In the present study of clinical pathophysiologic characteristics, we found that metastasis to the lymph nodes was associated with a significant reduction in the OPRT tumor/normal (T/N) ratio. Our results indicate that it may be possible to predict lymphatic metastasis by determining the T/N ratio for OPRT before surgery.
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PMID:[Correlation between clinical pathophysiologic factors and expression of orotate phosphoribosyl transferase (OPRT), thymidylate synthase (TS), and dihydropyrimidine dehydrogenase (DPD) in colorectal cancer]. 1191 31

Thymidine phosphorylase (TP) converts 5'-deoxy-5-fluorouridine (5'-DFUR, doxifluridine), an intermediate metabolite of capecitabine, to 5-fluorouracil (5-FU). While dihydropyrimidine dehydrogenase (DPD) catalyzes 5-FU to inactive molecules. We investigated TP and DPD levels in tumor tissue to assess their clinical significance as indicators for selecting colorectal cancer patients for 5'-DFUR adjuvant chemotherapy. A total of 88 colorectal cancer patients were classified into Dukes' B and C groups and treated for 2 years with oral 5'-DFUR (800 mg/body/day). During the follow-up period, 20 of the 88 patients developed a recurrence. All the patients were examined retrospectively for primary tumor TP and DPD levels and clinical response to 5'-DFUR. Results showed that: a) median levels of TP and DPD in the primary tumor, measured by enzyme-linked immunosorbent assay (ELISA), were, respectively, 43.6 and 32.3 U/mg protein. Primary tumor TP levels of the 20 patients who had a recurrence were lower than those of the 68 patients with no recurrence (p=0.07); b) although there were no significant differences in clinicopathologic features between high and low median TP level groups, disease-free survival was better in the high TP than in the low TP group (89% vs. 64%, at year 4); and c) of patients classified into 4 groups such as high TP/DPD, high TP but low DPD, low TP but high DPD, and low TP/DPD, patients with high TP but low DPD had the best disease-free survival, whereas the low TP but high DPD group had the worst survival. These results suggest that TP and DPD levels in primary colorectal tumors may be a useful indicator for selecting patients likely to respond to 5'-DFUR adjuvant chemotherapy and probably capecitabine, a prodrug of 5'-DFUR.
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PMID:Thymidine phosphorylase and dihydropyrimidine dehydrogenase levels in primary colorectal cancer show a relationship to clinical effects of 5'-deoxy-5-fluorouridine as adjuvant chemotherapy. 1195 13

Fluoropyrimidines remain the most important drugs in the treatment of breast and colorectal carcinoma, but response rates and survival time have been disappointing. Optimal administration is by continuous intravenous infusion, which makes it cumbersome to use and compromises patient independence. Recently, a number of new agents, including fluorouracil prodrugs and selective dihydropyrimidine dehydrogenase inhibitors, have been studied, with promising results. Capecitabine is the first in a new class of fluoropyrimidines. It is an oral, tumor-activated anticancer drug whose activity mimics that of continuously infused 5-fluorouracil. Capecitabine circumvents dihydropyrimidine dehydrogenase catabolism and appears to be at least as active against metastatic colorectal and breast cancer as conventionally administered intravenous 5-fluorouracil, with significantly less toxicity, an improved quality of life, and lesser cost. Capecitabine may ultimately provide enhanced antitumor activity to fluorouracil-containing regimes for advanced colorectal and breast cancer.
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PMID:Capecitabine: indications and future perspectives in the treatment of metastatic colorectal and breast cancer. 1198 87

Patients with advanced cervical carcinoma were treated with oral fluoropyrimidine (UFT) as neoadjuvant chemotherapy and its antitumor effect was examined. The relationship between thymidylate synthase (TS) or dihydropyrimidine dehydrogenase (DPD) activity in tumor tissue and apoptosis was also investigated. The subjects were 56 patients with advanced cervical carcinoma. The patients received two courses of therapy consisting of UFT at a dose of 600 mg/day for 5 days and 2 days off treatment. The TS and DPD activity in tumor tissue was measured before and after UFT administration by the FdUMP binding assay and a catalytic assay in 38 patients, respectively. Apoptosis was detected by the TUNEL method, and the apoptotic index (AI) was calculated. Tumor tissue activity of TS or DPD was unrelated to clinicopathologic factors or to the activity of the other enzyme. The mean tumor TS and DPD activity before UFT administration was 5.42+/-3.92 pmol/g tissue and 206.54+/-128.58 pmol/mg/min, respectively, and the levels of these enzymes in two patients showing an antitumor effect were below the mean values. The AI increased from 1.10+/-0.57% before UFT to 1.27+/-0.81% afterwards, and the DPD activity before UFT showed an inverse relationship with the AI after UFT (r=-0.6938). In patients with DPD activity below the median value (186.92 pmol/mg/min), UFT administration significantly caused an increase of the AI (p=0.0002). These results indicate that the DPD activity of advanced cervical carcinoma is a determinant of sensitivity to UFT, suggesting an association between UFT therapy and the induction of apoptosis.
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PMID:Tumor dihydropyrimidine dehydrogenase activity in advanced cervical carcinoma. 1216 69

We analyzed the interim results of prognostic significance of pyrimidine nucleoside phosphorylase (PyNPase), thymidylate synthase (TS), and dihydropyrimidine dehydrogenase (DPD) in 5-FU-based chemotherapy for breast cancer. In surgical specimens of tumor tissues and normal mammary gland tissues from 102 breast cancer patients, TS, PyNPase, and DPD activities were measured, and p53 and c-erbB-2 overexpression were also examined. TS, d-Thd-Pase/Urd-Pase (PyNPase), and DPD activities were significantly higher in tumor tissues than in normal tissues. There was a strong correlation between d-Thd-Pase and Urd-Pase in tumor tissues. No relationship was found between patient characteristics and any of the enzyme activities. PyNPase activities were significantly higher in the tissues having a c-erbB-2 overexpression of 75% (4+) or more than in those having less than 75%, and the tissues with a p53 of 50% (3+) or more had significantly higher TS activities than those with less than 50%. However, the other parameters showed no significant difference. The data obtained so far suggest no clear correlation between the activity of any of these enzymes and prognosis.
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PMID:[Significance of tissue PyNPase, TS, and DPD activities in breast cancer]. 1221 67

This study was designed to investigate the role of thymidine phosphorylase (TP) and dihydropyrimidine dehydrogenase (DPD) on tumour progression and sensitivity to 5'-deoxy-5-fluorouridine (5'-DFUR). Tumour tissue was obtained from surgically resected samples from 93 patients with primary gastric cancer. Tumour TP and DPD expression levels were determined by the enzyme-linked immunosorbent assay (ELISA) system and compared with several clinicopathological factors and in vitro sensitivity to 5'-DFUR. DPD showed no correlation with any clinicopathological factors. However, the TP level was significantly correlated with the depth of tumour, lymphatic invasion and venous invasion. In comparison with 5'-DFUR sensitivity, there was a weak inverse correlation between the DPD level and the sensitivity to 5'-DFUR (r(s)=-0.361). Furthermore, the TP/DPD ratio showed a significant correlation with 5'-DFUR sensitivity (r(s)=0.634). In a subgroup of patients with postoperative 5'-DFUR administration, the survival rate was significantly better in patients with a high TP/DPD ratio (n=8) than in those with low TP/DPD ratio (n=14) (P=0.0140). These results suggest that sensitivity to 5'-DFUR is predictable by measurement of both TP and DPD levels.
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PMID:Role of thymidine phosphorylase and dihydropyrimidine dehydrogenase in tumour progression and sensitivity to doxifluridine in gastric cancer patients. 1246 Jul 81

Mechanisms of anti-tumor action of 5-fluorouracil (5-FU) are presumed to inhibit DNA synthesis and RNA function, and the balance of these mechanisms is presumed to depend on the modalities of administration. On the other hand, variability of 5-FU sensitivity of the tumors is also presumed to depend on the enzymes of 5-FU metabolism (e.g. dihydropyrimidine dehydrogenase; DPD, rate limiting enzyme of catabolism) and action target (e.g. thymidylate synthase; TS). We studied the effects of modalities of administration and enzyme activities related to metabolism and target of 5-FU on the mechanism of anti-tumor action in patients with colorectal cancer. Thirty-eight patients who were diagnosed at stage II to IV preoperatively were enrolled. Patients were randomly assigned to receive 24-h protracted IV infusion of 5-FU at 320 mg/m(2)/day for 5 days (CIV group: 18 patients) or 10-min bolus IV infusion of 5-FU at the same dosage for 5 days (BIV group: 20 patients) administered from the 5th preoperative day. Specimens from the tumor and non-tumor regions were obtained by operation. F-RNA (fraudulent-RNA, or 5-FU in RNA) concentration, an indicator for action of 5-FU to RNA, and the enzyme activities of DPD and TS, an indicator for action of 5-FU to DNA, in the collected specimens were measured by GC-MS or RI-HPLC. F-RNA concentration (ng/mg-RNA) in the tumor and non-tumor region in the CIV group was 100.58+/-16.88 and 50.11+/-6.03, respectively, with a significant difference between them (P<0.05), and in the tumor and non-tumor region in the BIV group was 195.32+/-16.26 and 121.05+/-10.62, respectively, with a significant difference between them (P<0.01). F-RNA concentration in the tumor and non-tumor regions in the BIV group was significantly higher than those in the CIV group (P<0.05). DPD activity and TS activity were not significantly different between the CIV and the BIV groups in the tumor and non-tumor region, respectively. F-RNA concentration was negatively correlated to DPD activity (r=-0.540, P<0.05) in the tumor region in the CIV group. F-RNA was not correlated to DPD activity in the non-tumor region in the CIV group or in the tumor and non-tumor region in the BIV group. F-RNA was not correlated to TS activity in the tumor or non-tumor region of the two groups. DPD activity was not correlated to TS activity in the tumor or non-tumor region of the two groups. BIV inhibited RNA function more potently than CIV and this was not dependent on TS or DPD activity. As for the inhibition of DNA synthesis, other indicators should be considered further.
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PMID:Differential effects of two fluorouracil administration regimens for colorectal cancer. 1246 54


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