Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0038362 (stomatitis)
 8,852 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

5-Ethynyluracil (5-EU; 776C85) is a potent mechanism-based inactivator of dihydropyrimidine dehydrogenase that improves the antitumor activity of 5-fluorouracil (5-FU) to a greater extent than can be accounted for by the improved 5-FU pharmacokinetics that result from preventing the catabolism of 5-FU. We therefore tested the effects of (R)-5-fluoro-5,6-dihydrouracil (5-FUH2), the 5-FU catabolite extensively formed in the absence of 5-EU, on the antitumor activity and toxicity of 5-FU in 5-EU-treated rats bearing large s.c. tumors. Rats were dosed once weekly for 3 weeks with the following regimens: 100 mg/kg 5-FU (maximum tolerated dose), 10 mg/kg 5-FU 1 h after 1 mg/kg 5-EU, or 10 mg/kg 5-FU plus 90 mg/kg 5-FUH2 1 h after 1 mg/kg 5-EU. The latter regimen was designed to approximate the exposure produced from 5-FU in the absence of 5-EU, where > 80% of the dose is catabolized. 5-FU produced complete and sustained tumor regressions in 94% of the animals pretreated with 5-EU. In contrast, 5-FU in combination with 5-FUH2 produced complete regression in only 38% of the 5-EU-treated rats, which was similar to the antitumor activity of 5-FU in the absence of 5-EU. All treatments resulted in 7-11% transient weight loss. 5-FU produced no other notable toxicity in 5-EU-treated rats. However, 5-FUH2 added to this regimen caused transient diarrhea and stomatitis in 13% of the animals, which was similar to the toxicity produced by 5-FU in the absence of 5-EU. Thus, 5-FUH2, or other downstream catabolites of 5-FU, impaired the antitumor activity and slightly increased the toxicity of 5-FU. Accordingly, 5-EU approved to improve the efficacy of 5-FU by preventing the formation of 5-FU catabolites.
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PMID:Attenuation of the antitumor activity of 5-fluorouracil by (R)-5-fluoro-5,6-dihydrouracil. 788 16

5-Ethynyluracil (EU; 776C85) is a potent inactivator of dihydropyrimidine dehydrogenase, the enzyme that rapidly degrades 5-fluorouracil (FUra). We have investigated the antitumor activity and toxicity of FUra alone and in combination with EU in rats bearing advanced colon carcinoma. Two schedules were studied: (a) FUra daily for 4 days i.v. push (daily x 4); and (b) FUra administered i.v. push weekly for 3 weeks (weekly x 3). EU was administered at 1 mg/kg 1 h before FUra and for two additional days post-FUra therapy. The maximum tolerated doses of FUra alone were 35 and 100 mg/kg/day and for FUra plus EU were 10 and 15 mg/kg/day for the daily x 4 and weekly x 3 schedules, respectively. The dose-limiting toxicities were diarrhea and stomatitis both for FUra alone and for FUra in combination with EU. Although EU was not toxic and not active as an antitumor agent, it markedly improved the efficacy and therapeutic index of FUra. The antitumor activity of FUra was schedule dependent, yielding 13% complete and sustained tumor regression on the weekly schedule and no complete and sustained tumor regression on the daily schedule. The combination of FUra and EU produced 100% complete and sustained tumor regression on both schedules. The therapeutic index was < or = 1 for FUra alone and 6 for FUra with EU. EU was considerably more effective than either leucovorin or N-(phosphonacetyl)-L-aspartate as a modulator of FUra. Leucovorin or N-(phosphonacetyl)-L-aspartate induced minimum improvements on the daily schedule and only increased the therapeutic index to 1.5 on the weekly schedule. Because a 4-day continuous infusion of FUra alone at the maximum tolerated dose did not improve FUra therapy, we conclude that the improvements by EU involve additional modulations that complement the enhanced exposure of FUra.
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PMID:5-Ethynyluracil (776C85): modulation of 5-fluorouracil efficacy and therapeutic index in rats bearing advanced colorectal carcinoma. 813 56

In an effort to improve the therapeutic selectivity of 5-fluorouracil (FUra) against colorectal cancer, S-1, a combination agent including a prodrug of FUra with two modulators, was recently developed by Taiho Pharmaceuticals Co. S-1 is a combination of tegafur (FT), 5-chloro-2,4-hydroxypyridine, and potassium oxonate in the molar ratio of 1.0:0.4:1.0, with the latter two components as inhibitors of dihydropyrimidine dehydrogenase and phosphoribosylpyrophosphate transferase, respectively. In this study, the therapeutic selectivity and efficacy of S-1 (oral) was compared with FT (oral) and FUra (i.v. infusion) in rats bearing advanced colorectal cancer by using clinically relevant schedules. The maximum tolerated doses (MTDs) of S-1, FT, and FUra were 31.5, 200, and 25 mg/kg/d for 7 days and 22.5, 150, and 12.5 mg/kg/d for 28 days, respectively. The therapeutic index of S-1 was 4- to 5-fold higher than that of either FT or FUra. S-1 achieved 100% complete tumor regression (CR) at its MTD in both 7-day and 28-day schedules. Furthermore, the high incidences of stomatitis, alopecia, and diarrhea observed with FUra and FT, were not observed with S-1. In an attempt to understand the basis for the observed superior therapeutic selectivity with S-1, we studied pharmacokinetic analysis of FUra, drug-induced apoptosis, suppression of mitosis, and inhibition of thymidylate synthase (TS) after S-1, FUra, or FT administration. The peak plasma FUra concentrations derived from FUra or S-1 (FT) at comparable MTDs were similar, but the plasma level of FUra was higher with S-1 than with FUra. Induction of high and sustained apoptosis was achieved with S-1. Although the initial level of apoptosis induced by FUra was comparable to S-1, it was not sustained. The sustained level of apoptosis appears to correlate with tumor growth inhibition. Mitotic figures were more greatly suppressed with S-1 treatment than with FUra. Studies on TS inhibition indicated that, although both S-1 and FUra caused a 4- to 6-fold induction of total TS protein, single oral administration of S-1 was superior to 24-h infusion of FUra in suppressing free TS. The data are consistent with the observation that the therapeutic efficacy of S-1 (100% cure) over FUra is associated with high and sustained levels of drug-induced apoptosis, greater suppression of mitosis, and inhibition of free TS in tumor tissues.
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PMID:Persistent induction of apoptosis and suppression of mitosis as the basis for curative therapy with S-1, an oral 5-fluorouracil prodrug in a colorectal tumor model. 1003 74

In humans, 80-90% of an administered dose of 5-fluorouracil (5-FU) is degraded by dihydropyrimidine dehydrogenase (DPD; EC 1.3.1.2), the initial rate-limiting enzyme in pyrimidine catabolism. Cancer patients with decreased DPD activity are at increased risk for severe toxicity including diarrhea, stomatitis, mucositis, myelosuppression, neurotoxicity, and, in some cases, death. We now report the first known cancer patient who developed life-threatening complications after treatment with topical 5-FU and was shown subsequently to have profound DPD deficiency. RT-PCR and genomic PCR methodologies were used to identify a G to A mutation in the GT 5' splicing recognition sequence of intron 14, resulting in a 165-bp deletion (corresponding to exon 14) in this patient's DPD mRNA. Immunoprecipitation and Western blot analysis were then used to demonstrate that the aberrant DPD mRNA is translated into a nonfunctional DPD protein that is ubiquitinated. We conclude that the presence of this metabolic defect combined with topical 5-FU (a drug demonstrating a narrow therapeutic index) results in the unusual presentation of life-threatening toxicity after treatment with a topical drug. These data further suggest that degradation by the ubiquitin-proteosome-mediated system plays a role in the elimination of the DPD protein.
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PMID:Life-threatening toxicity in a dihydropyrimidine dehydrogenase-deficient patient after treatment with topical 5-fluorouracil. 1047 70

Recently, a demand for therapy of higher usefulness in cancer patients has increased. We described in this paper a therapeutic modality which is based on SRC (self-rescuing concept) featuring dual activity, i.e., effect-enhancing activity and adverse reaction-reducing activity. We presented the theory and practice of S-1, a novel oral fluoropyrimidine anti-cancer agent designed to enhance anticancer activity and reduce gastrointestinal toxicity through the deliberate combination of the following components: an oral fluoropyrimidine agent tegafur; a DPD inhibitor (CDHP) which is more potent than uracil used in UFT; and an ORTC inhibitor (Oxo) which localizes in the gastrointestinal tract. S-1, as a combination drug with a molar ratio of 1:0.4:1 in FT, CDHP, and Oxo, respectively. A clinical pharmacology study to examine blood concentrations of 5-FU after twice-a-day administration of S-1 at a dose 40 mg/m2. Consequently , blood concentrations of 5-FU were 60 to 200 ng/m/ in all twelve patients examined. The overall response rate was 44.6% (45/101). In addition, the incidence of adverse reactions judged to be G3 or higher was 10% or less. Furthermore, we referred to combination therapy with 5-FU (CIV)(5-FU: 250 to 350 mg/body, 24-hour CVI, consecutive days) and low-dose cisplatin (CDDP: 3 to 5 mg/body, iv, 5 days/week) in which CDDP was used as modulator of 5-FU. Low-dose FP therapy provided response rates as high as 40 to 60% in 163 patients with sorts of gastrointestinal cancers except pancreas cancer. The incidence of adverse reactions which were judged to be G3 or higher was 2.5% (4/163) in nausea and vomiting. The incidences of other adverse reactions were 1% or less. And to the theory and practice of combination therapy with 5-FU (CVI) 24-hour CVI; 5-FU: 750 to 1000 mg/body/day on Monday, Wednesday, and Friday; withdrawal on Tuesday, Thursday, Saturday, and Sunday) intermittent administration and low-dose CDDP (3 to 5 mg/body/day day 1-5/w) consecutive administration in which a difference in cell cycle between gastrointestinal mucosal cel l and tumor cell or between bone marrow cell and tumor cell was utilized . Little adverse reactions, e.g., diarrhea and stomatitis, were observed despite the overall response rate which was as high as 52.4% (22/42). We intend in the future to combine the above mentioned therapeutic modalities provoking less adverse reactions and being gentle to patients with cancer in an effort to further increase their life expectancy.
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PMID:Conceptual changes in cancer chemotherapy--biochemical modulation of 5-FU from bench to clinic. 1089 55

Recently, the demand for more useful therapies for cancer patients has increased. We describe in this paper a therapeutic modality based on a self-rescuing concept (SRC), and which features dual activity, i.e., an effect-enhancing activity and an adverse reaction-reducing activity. We present the theory and practice of S-1, a novel oral fluoropyrimidine anticancer agent designed to enhance anticancer activity and reduce gastrointestinal toxicity through the deliberate combination of the following components: the oral fluoropyrimidine agent tegafur; a DPD inhibitor (CDHP) which is more potent than uracil, which is used in UFT; and an ORTC inhibitor (Oxo) which localizes in the gastrointestinal tract. S-1 is a combination drug with a molar ratio of 1:0.4:1 in FT, CDHP, and Oxo, respectively. A clinical pharmacology study was conducted to examine blood concentrations of 5-FU after twice-a-day administration of S-1 at a dose of 40 mg/m2. Blood concentrations of 5-FU were found to be 60 to 200 ng/ml in all twelve patients examined. The overall response rate was 44.6% (45/101). In addition, the incidence of adverse reactions judged to be grade 3 or higher was 10% or less. We have also reported a combination therapy with 5-FU (civ) (5-FU: 250 to 350 mg/body, 24-hour cvi, consecutive days) and low-dose cisplatin (CDDP: 3 to 5 mg/body, i.v., 5 days/week), in which CDDP was used as a modulator of 5-FU. Low-dose FP therapy provided response rates as high as 40 to 60% in 163 patients with various gastrointestinal cancers other than pancreas cancer. The incidence of the adverse reactions of nausea and vomiting which were judged to be grade 3 or higher was 2.5% (4/163). The incidences of other adverse reactions were 1% or less. In line with the theory and practice of combination therapy with 5-FU (cvi) 24 hr cvi; 5-FU: 750 to 1,000 mg/body/day on Monday, Wednesday, and Friday (withdrawal on Tuesday, Thursday, Saturday and Sunday) intermittent administration and low-dose CDDP (3 to 5 mg/body/day day 1-5/w) consecutive administration was utilized in which there was a difference in cell cycle between gastrointestinal mucosal cell and tumor cell, or between bone marrow cell and tumor cell. Few adverse reactions, e.g., diarrhea and stomatitis, were observed despite the overall response rate being as high as 52.4% (22/42). The incidence of adverse reaction judged to be grade 3 or higher was as low as 9.3% (5/54), with an incidence of 9.3% (5/54) in Grade 3 or higher myelotoxicity. We intend in the future to combine the abovementioned therapeutic modalities, which provoke fewer adverse reactions and are easy on patients with cancer in an effort to further increase their life expectancy.
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PMID:[Conceptual changes in cancer chemotherapy--biochemical modulation of 5-FU]. 1089 9

The conventional concept in cancer chemotherapy considers that no efficacy can be attained without provoking adverse reactions. We presented concrete descriptions based on a novel concept allowing us to emerge from the old one. Relief of adverse reactions, e.g., diarrhea, stomatitis, anorexia, and H&F syndrome, not only improves QOL of the patient but also allows prolongation of the treatment period without lowering patient compliance. We describe in this paper a therapeutic modality which is based on SRC (self-rescuing concept) featuring dual activity, i.e., effect-enhancing activity and adverse reaction-reducing activity. We present the theory and practice of S-1, a novel oral fluoropyrimidine anticancer agent designed to enhance anticancer activity and reduce gastrointestinal toxicity through the deliberate combination of the following components: an oral fluoropyrimidine agent tegafur; a DPD inhibitor (CDHP) which is more potent than uracil used in UFT; and an ORTC inhibitor (Oxo) which localizes in the gastrointestinal tract. Furthermore, we refer to combination therapy with 5-FU (CIV) and low-dose consecutive CDDP in which CDDP was used as a modulator of 5-FU and to the theory and practice of combination therapy with 5-FU (CVI) intermittent (Monday, Wednesday, and Friday) administration and low-dose CDDP consecutive administration in which a difference in cell cycle between gastrointestinal mucosal cell and tumor cell or between bone marrow cell and tumor cell was utilized. We intend in future to combine the abovementioned therapeutic modalities provoking less adverse reactions and being gentle to patients with cancer in an effort to further increase their life expectancy.
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PMID:Conceptual changes in cancer chemotherapy: from an oral fluoropyrimidine prodrug, UFT, to a novel oral fluoropyrimidine prodrug, S-1, and low-dose FP therapy in Japan. 1108 68

We describe in this paper a therapeutic modality which is based on a self-rescuing concept (SRC) featuring dual activity, i.e., effect-enhancing activity and adverse reaction-reducing activity. We present the theory and practice of S-1, a novel oral fluoropyrimidine anticancer agent designed to enhance anticancer activity and reduce gastrointestinal toxicity through the deliberate combination of the following components: an oral fluoropyrimidine agent, tegafur (FT); a DPD inhibitor (CDHP: 5-chloro-2, 4-dihydroxypyridine) which is about 200-fold more potent than uracil used in UFT; and an ORTC inhibitor (Oxo: potassium oxonate) which is localized in the gastrointestinal tract. We devised a novel oral anticancer agent, S-1, as a combination drug with a molar ratio of 1:0.4:1 for FT, CDHP, and Oxo, respectively. To compare S-1, FT, and UFT in terms of their anticancer activity and adverse reactions, a colon cancer implantation model in rats was used for 4-week consecutive oral administration from the time when the postimplantation tumor weight become about 2 g. The tumor disappeared on day 16 at a given dose of S-1 (as 22.5 mg/kg FT), and the tumor did not reappear for at least three months. Antitumor activity was more marked with S-1 than FT and UFT. Adverse reaction, i.e., stomatitis, depilation, and weight loss, were less frequent in the S-1 group than in the other groups. A clinical pharmacology study examined blood concentrations of 5-FU after twice-a-day administration after meals of S-1 at a dose of 40 mg/m2. Blood concentrations of 5-FU were 60 to 200 ng/ml in all twelve patients examined. Late phase II clinical trials of S-1 were conducted in patients with advanced and recurrent stomach cancers, in the same regimen as for the clinical pharmacology study. It basically consisted in four cycles, each of which comprised 4-week, twice-a-day, consecutive oral administration with a 2-week withdrawal. The overall response rate was 44.6% (45/101). Median survival time (MST) was 224 days. S-1 was given manufacturing approval by the Ministry of Health and Welfare of Japan after a priority review, with indications for advanced and recurrent stomach cancers. A late phase II clinical study of S-1 in patients with advanced/recurrent head and neck cancer was conducted in 59 eligible patients. Objective responses were 4 complete response (CR) and 13 partial response (PR), for a response rate of 28.8% (17/59). MST was 344 days. Grade 4 hemoglobin decrease was observed in one case; however, this returned to normal after the termination of drug administration and blood transfusion. Therefore, this event was confirmed to be reversible. A late phase II clinical trial of S-1 was conducted to evaluate the efficacy and toxicities in patients with metastatic colorectal carcinoma. Sixty-three patients with measurable metastatic colorectal carcinoma were enrolled in this clinical trial. The overall response rate was 35.5% (22/62), and the MST was 378 days. The main adverse reactions were myelosuppression and GI toxicities. The incidence of neutropenia (Grade 3 or 4) was 13%, while the incidence of other adverse reactions was 10% or below. None of 53 outpatients required to be hospitalization due to adverse reactions. Late phase II clinical trials of S-1 are in progress for colorectal cancer, breast cancer and non-small cell lung cancer. To establish the standard therapeutic modality for cancers, including gastrointestinal cancers, in Japan, the conduction of clinical trials combining S-1 and other anticancer drugs holds promise for the future.
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PMID:[New oral anticancer drug, TS-1 (S-1)--from bench to clinic]. 1143 58

TS-1, a DPD inhibitory fluoropyrimidine, is a novel oral formation of 5-fluorouracil (5-FU). In patients with advanced gastric cancer, the response rate was reportedly over 40%. We report three cases of advanced gastric cancer treated using TS-1 in combination with a low-dose of cisplatinum (CDDP) that well responded. Case 1: A 62-year-old women underwent total gastrectomy. Ten weeks later, she suffered intestinal obstruction due to peritoneal recurrence of gastric cancer. Eighty mg of TS-1 in combination with bi-weekly administration of CDDP (10 mg) improved her intestinal obstruction. Case 2: A 50-year-old man suffered peritoneal recurrence of gastric cancer. Computed tomography (CT) showed intestinal obstruction, ascites, and hydronephrosis. After 100 mg of TS-1 in combination with bi-weekly administration of CDDP (20 mg) for 1 year, CT showed almost complete improvement of peritonitis carcinomatosa. Case 3: A 58-year-old man, who suffered advanced gastric cancer with peritonitis carcinomatosa, was administrated 100 mg of TS-1 in combination with bi-weekly administration of CDDP (20 mg). After 2 months of administration, remarkable improvement was observed in the upper gastrointestinal series. Adverse reactions, which were grade 1 for stomatitis, were observed only in case 1. All three patients are alive (case 1 and 2 have survived more than one year) and therapy is continuing. In conclusion, combined chemotherapy of TS-1 and low-dose CDDP was effective and well tolerable for advanced gastric cancer patients. It was suggested that effective biochemical modulation might be achieved by these two drugs.
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PMID:[Three cases of advanced gastric cancer treated by TS-1 in combination with low-dose cisplatinum]. 1186 38

This study investigated the relationship among the pharmacokinetics of 5-fluorouracil (5-FU) and 5-fluoro-5,6-dihydrouracil (5-FDHU); the activity of dihydropyrimidine dehydrogenase (DPD) in peripheral blood mononuclear cells; and treatment-related toxicity in 26 patients with surgically resected colorectal cancer treated with short daily infusions of 5-FU adjuvant chemotherapy, each cycle consisting of 5 consecutive days every 4 weeks. After the first chemotherapeutic cycle, severe stomatitis and diarrhea occurred in 5 patients and were related to the variations in the systemic disposition of the drug rather than to DPD activity. These patients showed a significant decrease in 5-FU clearance, and an increase in the 5-FU/5-FDHU area under the time-concentration curve (AUC) ratio, as compared with patients who experienced mild toxicities, whereas a low DPD activity was observed in only 2 patients. In conclusion, the results of this study demonstrate that the alterations in 5-FU and 5-FDHU pharmacokinetics are related to severe toxicities in patients treated with short intravenous infusion of 5-FU.
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PMID:Relationship between plasma concentrations of 5-fluorouracil and 5-fluoro-5,6-dihydrouracil and toxicity of 5-fluorouracil infusions in cancer patients. 1235 29


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