Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0699790 (colon cancer)
 28,837 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We conducted a phase I trial of fluorouracil (5-FU), leucovorin, (LCV), and recombinant interferon-alpha-2b (rIFN-alpha-2b). The doses of each of the three agents were escalated sequentially. 5-FU and LCV were administered by IV bolus, weekly for 6 weeks and rIFN-alpha-2b was administered by subcutaneous injection, three times weekly for 6 weeks. Twenty-nine patients with advanced cancer (75% colon or pancreatic cancer) were treated. Partial remissions were observed in three patients (10%) with previously untreated colon cancer, colon cancer refractory to 5-FU plus LCV and previously untreated pancreatic cancer, respectively. An additional three patients with pancreatic, prostate, and rectal cancer had a 50% reduction in tumor markers but no change in objective tumor measurements. The toxicity of this regimen was tolerable. The most common toxicities were diarrhea, fatigue, flu-like symptoms, nausea/vomiting, and mucositis. However, no fatal or life-threatening toxicities were observed. We conclude that the combination of 5-FU, LCV, and rIFN-alpha-2b can be safely administered and recommend further evaluation of this regimen in patients with tumors of gastrointestinal origin using doses of 5-FU 600 mg/m2, LCV 500 mg/m2, and rIFN-alpha-2b 10 x 10(6) U.
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PMID:A phase I trial of fluorouracil, leucovorin, and recombinant interferon alpha-2b in patients with advanced malignancy. 155 45

Interferon has been shown to augment the cytotoxic effects of fluorouracil (5-FU) against colon cancer in vitro and possibly in vivo. Therefore a pilot study was initiated to evaluate the effects of the combination 5-FU/FA/interferon alfa (IFN-alpha) in colorectal adenocarcinomas refractory to first-line therapy with 5-FU/FA. Eleven patients with rectum cancer and four patients with colon cancer were treated according to the following schedule: 9 million units IFN-alpha subcutaneous three times a week; 500 mg/m2 5-FU via an intravenous bolus 1 hour after the initiation of a 2-hour infusion of 500 mg/m2 of FA, once a week. Of 15 patients, one had a minor response, one had a disease stabilization, and three had a mixed response. No complete or partial remissions were seen. Looking at the sensitivity of lung metastases (three of three), the regressions can be explained through the additive effect of IFN-alpha to 5-FU/FA. Although minimal side effects (World Health Organization classification) were observed, most patients experienced a reduction of well-being.
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PMID:Treatment of refractory colorectal carcinomas with fluorouracil, folinic acid, and interferon alfa-2a. 155 48

Leucovorin and interferon are capable of modulating the cytotoxicity of fluorouracil (5-FU). Preclinical studies demonstrate that d,l-leucovorin is rapidly metabolized in human breast and colon cells into the various one-carbon substituted folate pools and to the polyglutamated state. While increases in intracellular folate pools are proportional to the exposure concentration of leucovorin, relatively large increases in leucovorin concentrations (50- to 100-fold) are required to produce small intracellular changes (twofold). Polyglutamation is favored by prolonged exposures to leucovorin. Polyglutamate forms have a prolonged intracellular retention and a higher affinity for the target enzyme, thymidylate synthase. Ratios of up to 20:1 inactive to active leucovorin stereo-isomers had essentially no effect on the intracellular metabolism of the active isomer. Interferon gamma interacts with 5-FU in H630 colon cancer cells at the level of thymidylate synthase and enhances cytotoxicity of 5-FU by eliminating the 5-FU-induced acute overexpression of the target enzyme. No alterations in the intracellular metabolism or nucleic acid incorporation of 5-FU could be demonstrated with the addition of interferon gamma. A clinical trial combining interferon-alfa-2a (IFN-alpha-2a) (subcutaneous days 1 to 7) with 5-FU and leucovorin (given IV days 2 to 6) demonstrated that these agents could be combined with acceptable toxicity. While the addition of interferon did not allow dose escalation of 5-FU, it resulted in a significant increase in drug exposure (1.5-fold) compared with matched cycles of 5-FU plus leucovorin without interferon. The overall response rate in this pilot study of 13 untreated patients with gastrointestinal adenocarcinoma was 46%, including two complete responses. There were no responses in eight patients who had previously failed therapy with 5-FU.
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PMID:Biochemical modulation of fluorouracil with leucovorin and interferon: preclinical and clinical investigations. 155 56

Interferon alfa has been demonstrated to enhance the effect of fluorouracil (5-FU) on human colon cancer cell lines as well as in clinical studies. By several authors interest in focussed on the question whether the interaction between these two agents is reflected by changes of 5-FU kinetics. In the present study the pharmacokinetic behavior of 5-FU was investigated in combination with interferon alfa (IFN-alpha-2b) and further after adding the second well-established biomodulating agent folinic acid (FA). Ten patients with advanced gastrointestinal cancer received 5-FU as a weekly bolus injection of 750 mg/m2, IFN-alpha-2b 5 million units three times per week subcutaneously and FA as a short time infusion at 200 mg/m2. 5-FU plasma levels were determined by high performance liquid chromatography as a baseline measurement on day 1 before starting IFN-alpha-2b. Analysis was repeated at the second or third cycle of 5-FU administration 1 hour after the last IFN-alpha-2b injection, and finally after also adding FA immediately infused before 5-FU injection. Biomodulation of 5-FU by IFN-alpha-2b alone resulted in a significant alteration of 5-FU kinetic parameters as demonstrated by an increase of area under the curve by 80%, and of blood concentration (co) by 65%, and a decrease of total clearance at 50%. These data may partly explain the observed enhancement of antiproliferative and toxic effects of this combination. On the other hand, when FA was added to this schedule, no significant changes of 5-FU kinetics could be documented. Therefore the theoretical benefit of such a double modulation cannot be supported by our findings. Further preclinical and clinical investigations are required to define the role of a triple combination of 5-FU with IFN-alpha-2b and FA.
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PMID:Influence of interferon alfa-2b with or without folinic acid on pharmacokinetics of fluorouracil. 155 61

Recently, levamisole combined with 5-FU was shown definitively to increase the survival of patients after surgery for colon cancer (9, 10). In the light of these findings the experimental and clinical findings with levamisole in the field of oncology are reviewed. The conclusion is reached that levamisole has proven activity, although its mechanism of action remains elusive. The progress that has been made in our understanding of immunology in general, the remarkable advance in experimental and diagnostic tools and the recent emergence of new indications of levamisole's interaction with immunosuppressive factors and interleukins all together warrant sufficient optimism to engage in a renewed clinical and experimental research effort. The outcome may be rewarding not only in terms of optimised treatment of patients with levamisole but also a more rational search for more potent successors may become feasible.
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PMID:Levamisole in the treatment of cancer: anything new? (Review). 156 66

The prognosis of colon cancer after curative resection is mainly related to the onset of metastases, and especially of liver metastases. In order to prevent metastatic recurrences, the value of adjuvant medical therapy is widely admitted. The aim of the present review was to analyse the conclusions of the main recent randomized trials assessing the comparative value of different adjuvant protocols. The results obtained using either classic systemic infusion or intraportal infusion, which is mainly used with the intent of preventing liver metastases, are reported. At term of this review, we conclude that: adjuvant chemotherapy using combined drugs (5-Fluorouracil + Methyl CCNU, 5-Fluorouracil + Oncovin) did not prove to be more active than 5-FU alone. the beneficial action of a combined 5-FU + Levamisole regimen has been clearly demonstrated for patients with a Dukes C tumor. intraportal adjuvant therapy has been shown to be effective for patients with Dukes B tumors in only one limited trial but this remains to be confirmed. On the basis of the present data, new adjuvant programs using combined chemotherapeutic and immunotherapeutic compounds, and combined systemic and regional infusion, can be envisaged.
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PMID:[Does an efficacious adjuvant treatment exist in resected colonic carcinoma?]. 158 19

Levamisole, which had been used as an insecticide for more than 20 years, was reported to have anticancer effects as an immunopotentiator. Among many clinical trials with this agent, Moertel and his colleagues reported excellent results in Dukes-C colon cancer patients treated with 5-FU and levamisole in 1990. In this paper, results of our animal experiments would be reported in conjunction with the review of the recent clinical trials.
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PMID:[Combined therapy with 5-FU and levamisole]. 162 53

Fluorouracil (FUra) is the most active agent in advanced colorectal carcinoma, and this activity can be enhanced by various modulating agents both in vitro and in vivo. To determine whether interferon (IFN) is capable of augmenting the cytotoxic and cytokinetic effects of FUra, combinations of FUra and IFN alpha, -beta, and -gamma were tested against 2 human colon cancer cell lines in vitro. In a clonogenic assay, IFN alpha and -beta, at concentrations that produced less than 1 log cell kill, significantly increased the cytotoxic effects of FUra in both cell lines. IFN gamma also enhanced the cytotoxic effects of FUra, but unlike IFN alpha and -beta, only at the highest concentrations tested. Median effects analysis demonstrated that all 3 IFNs exhibited synergy with FUra. Combinations of IFNs were no more effective at modulating FUra activity than single agent IFN. Flow cytometric studies indicated that these effects did not correlate with cytokinetic alterations. Only the combination of FUra and IFN beta produced cytokinetic effects different from those of FUra alone. Incubation with IFN alpha or IFN gamma for 24 h resulted in only modest cytokinetic alterations, and they did not modify the effects of FUra. These results indicate that IFN is capable of increasing the cytotoxic actions of FUra and that this is separable from any cytokinetic effects produced by the interferons.
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PMID:Interaction of fluorouracil and interferon in human colon cancer cell lines: cytotoxic and cytokinetic effects. 169 99

Recent clinical trials demonstrate the combined activity of 5-fluorouracil (5-FU) and interferon (IFN) in advanced colon cancer. Several possibilities exist for explaining the interaction. Interferon may alter the pharmacokinetics of 5-FU infusion by increasing the steady state concentration. Interferon enhances the inhibitory effects of 5-FU for tumor cells in culture. This enhancement is blocked by thymidine. Interferon reduces the concentration of thymidylate synthetase, and this may account for the thymidine-reversible interaction. An alternative mechanism invokes the immunomodulatory effects of IFN. Interferon augments the activity of killer cells with possible anti-tumor activity, both in vitro and in vivo. Also, by increasing the expression of human leukocyte class I antigens, IFN reduces the sensitivity of tumor cell lines to cell-mediated killing, an effect termed resistance. 5-Fluorouracil reverses the resistance in a time- and dose-dependent manner. The effect is mediated through inhibition of protein synthesis, since thymidine cannot reverse it. Fluorouridine is more active in reversing resistance than fluorodeoxyuridine. 5-Fluorouracil also reverses the induction of human leukocyte antigens by IFN. Studies in the resistance model suggest that high doses of 5-FU by infusion for several days might be the optimal method for modulation of IFN-induced effects.
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PMID:Mechanisms of interaction of interferon and 5-fluorouracil in solid tumors. 171 44

A human colon cancer cell line Hce-8693 was heterotransplanted in nude mice. polyamine biosynthesis inhibitor alpha-difluoromethylornithine (DFMO) showed a marked reproducible inhibition in this model. The size and weight of transplanted tumor in DFMO group were smaller than those of the control group and the average inhibition rate was 72.8% (P less than 0.001). DFMO showed higher tumor inhibitory rate than 5-Fu (35.4%) (P less than 0.001). Furthermore, DFMO demonstrated less severe bone marrow inhibition in the nude mice than 5-Fu (20.0% vs 53.2%, P less than 0.001). There was no synergistic action in these two drugs at the experimental doses. The concentration of putrescine and spermidine in the serum and tumor tissue in the DFMO group were 70% lower than those of the control group (P less than 0.001). These results indicate that the anti-tumor effect of DFMO might be explained by the inhibition of polyamine biosynthesis and this study provides an experimental basis for future clinical application of DFMO.
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PMID:[Inhibition by polyamine biosynthesis inhibitor DFMO of the growth of transplanted human colon cancer in nude mice]. 178 43


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