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)

The combination of the antimetabolite fluorouracil plus the immunomodulator levamisole is used as adjuvant therapy following surgical tumour removal in patients with Dukes' stage C colon cancer. Fluorouracil given alone in this setting results in only a modest improvement in survival rate, and levamisole monotherapy is clinically ineffective. Well controlled studies, however, demonstrate that combined levamisole/fluorouracil reduces the recurrence rate by between 31 and 41% and the total mortality rate by between 13 and 33% compared with surgery alone in patients with Dukes' stage C colon cancer after median follow-up of 3 or 7.75 years. The median time to recurrence and median survival time are also extended significantly by levamisole/fluorouracil compared with fluorouracil alone or no adjuvant treatment. Thus, levamisole/fluorouracil has been recommended as the standard adjuvant therapy for patients with Dukes' C colon cancer, against which new investigative regimens should be compared. Methods for optimising the impressive results already achieved with this combination, and using this as a basis for further progress should be the thrust of future trials.
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PMID:Levamisole/fluorouracil. A review of their pharmacology and adjuvant therapeutic use in colorectal cancer. 179 23

5-Fluorouracil (5-FU) remains the most effective chemotherapeutic agent in the management of patients with metastatic colorectal cancer. Leucovorin enhances its efficacy, but also its toxicity. Cited data suggest modulation of 5-FU toxicity by high dose allopurinol. In a prospective randomized trial we assessed the ability of allopurinol in a conventional dose to modulate the toxicity of 5-FU-leucovorin combination without compromising its efficacy in 50 patients with advanced colorectal cancer. Twenty-seven patients were randomized for allopurinol but had no benefit in terms of response or reduced toxicity over the other 23. Survival of responders with colon cancer was longer than that of non-responders (p = 0.013). Although allopurinol failed to reduce 5-FU-leucovorin toxicity, it did not lower its expected efficacy.
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PMID:Treatment of advanced colorectal cancer by 5-fluorouracil-leucovorin combination with or without allopurinol: a prospective randomized study. 180 86

5-Fluorouracil (5-FU) is an anticancer drug used in patients for the treatment of gastric and breast cancer and used either alone or in combination with methotrexate is one of the few drugs with some effect on colon cancer. 2'-Deoxy-5-fluorouridine (5-FUdr) (1) is an analogue based on 5-FU and can be covalently linked to a murine anti-Ly-2.1 monoclonal antibody (mAb) with the active ester derivative of 2'-deoxy-5-fluoro-3'-O-(carboxypropanoyl)uridine (5-FUdr-succ) (4). Such immunoconjugates can contain up to 42 residues of drug, although the most antibody activity was retained when substitution ratios were between 10 and 25 molecules of drug to mAb. In a cytotoxicity assay, 50% inhibition of [3H]deoxyuridine incorporation (IC50) with a murine Ly-2.1+ve thymoma cell line was 6 nM for 5-FUdr-anti-Ly-2.1, which is 12-fold more than that for free 5-FUdr (IC50 = 0.51 nM) but similar to that of 5-FUdr-succ (IC50 = 5.2 nM). The 5-FUdr-monoclonal antibody conjugates (5-FUdr-mAb) were 100-fold more active on the Ly-2.1+ve E3 cell line than on the Ly-2.1-ve BW5147 OU- cell line. The high in vitro activity and specificity of 5-FUdr-MoAb conjugates indicates that potent in vivo activity of these conjugates should be expected.
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PMID:In vitro antitumor activity of 2'-deoxy-5-fluorouridine-monoclonal antibody conjugates. 183 Oct 49

The establishment of reliable preclinical test is essential for the reasonable clinical trial. As a methodology for the screening of new active anticancer agents, disease oriented strategy using human tumor cell lines has been proposed in USA. The important questions in DOS are to determine the representative cell lines of specific cancer and it is also extremely important to decide the numbers of cell lines used for the screening. CPT-11, topoisomerase I inhibitor, developed in my country has been demonstrated to be active against lung cancer cell lines compared with mice tumors such as S-180 and P-388. However, no compound is demonstrated to be clinically active so far by this methodology. The criteria for the application of clinical trial are obscure and each drug company decides empirically by themselves. We have proposed to use PEI (predictive efficacy index) for the prediction of antitumor activity of new compounds. The clinical effect of new platinum analogue well correlated with this value. We have conducted phase II trial of 5-FU + LV against NSCLC without no prior chemotherapy. No responder was observed in the trial. Augmentive effect of leucovorin on the cytotoxicity of 5-FU and FdUrd was examined in vitro against NSCLC and colon cancer cell lines. Leucovorin stimulated the cytotoxicity of both drugs only against colon cancer cell lines. We tried to predict the response rate of new platinum derivative based on the data of bioassay of patient's serum administrated with platinum compounds. The predicted response rates of 254-S were 57-67% and 16-27% against SCLC and NSCLC, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Preclinical trials from the standpoint of clinical trials]. 185 17

Leucovorin potentiates the cytotoxicity of fluorouracil (5-FU) in experimental tumor systems and appears to enhance the effectiveness of 5-FU in patients with colon cancer. Twenty-two eligible patients (18 previously untreated) with advanced pancreatic adenocarcinoma were treated in a phase II trial of leucovorin 500 mg/m2/d for 6 days by continuous intravenous infusion with 5-FU 370 mg/m2/d by rapid intravenous injection on 5 consecutive days, beginning 24 hours after initiation of leucovorin infusion. Among the 20 assessable patients, there were no complete or partial regressions, although there was one minor response lasting 4 months. Three patients had stable disease for 5, 20, and 21 months, respectively. Median survival was 10 weeks. Toxicity was predominantly mucosal; stomatitis grade 2 or worse was seen in five patients, and diarrhea grade 2 or worse was seen in four. Hospitalization for toxicity was necessary in four previously untreated patients and three previously treated patients. The median WBC nadir was 4.6 (range, 1.4 to 9.6) x 10(3)/microL, and the median platelet nadir was 147.0 (range, 69.0 to 240.0) x 10(3)/microL. This combination of leucovorin and 5-FU did not demonstrate meaningful therapeutic activity in patients with adenocarcinoma of the pancreas and was associated with moderate to severe toxicity. It should not be considered a standard treatment for patients with this disease.
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PMID:Lack of efficacy of high-dose leucovorin and fluorouracil in patients with advanced pancreatic adenocarcinoma. 187 24

Analysis of cell kinetics may be beneficial for evaluation of the therapeutic effect of anticancer agents. Therefore, using flow cytometry, the authors could classify perturbations of DNA histogram of cultured colon cancer cells treated with 5-FU into 4 types. Perturbation of DNA histogram of cancer cells treated with 5-FU of different concentrations was closely associated with the degree of cell damage indicated by the growth curve. Then, tumor samples before and after injection of 5-FU were collected from 9 preoperative patients with colon cancer and classified into the above 4 types. The results show that 2 cases were classified into type I (S/G1 ratio: 1.5 greater than, G1.G2M comparison: G1 greater than G2M) and another two into type IV (CV ratio: 1.5 less than or equal to, S/G1 ratio: 1.5 less than or equal to, G1.G2M comparison: G1 greater than G2M). However, 5 cases could not be classified (not evaluated) because of the absence of stemline and the presence of heterogeneity in tumor samples. The authors consider that the classification of perturbation of DNA histogram is a useful method to evaluate the degree of cell damage with 5-FU, if tumor samples are appropriately selected and analysis is made with careful attention.
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PMID:[Classification of DNA histogram perturbed with 5-FU and its clinical application]. 188 80

In an attempt to reduce disease recurrence after curative resection of transmural or node positive colon cancer, the Gastrointestinal Tumor Study Group performed a randomized trial of observation versus 5-FU plus 2100 cGy to the liver. A total of 300 eligible trial participants form the basis of this report. Significant toxicity after the combination caused major dose reduction from the original course of 500 mg/m2 to 350 mg/m2. No therapeutic benefits were noted in either survival or recurrence endpoints; the liver recurrence rate was not decreased by the therapy. Analysis of patients with transmural colonic involvement and negative nodes, one to four positive, and greater than four positive nodes indicates that not all patients are alike with respect to disease outcome or overall survival, and that node number is an important determinant of patient selection for adjuvant trials.
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PMID:Adjuvant therapy with hepatic irradiation plus fluorouracil in colon carcinoma. The Gastrointestinal Tumor Study Group. 193 12

Fluorouracil (5-FU) is still the mainstay of adjuvant treatment for colorectal cancer. Two trials have shown a disease-free and overall survival benefit for 5-FU combined with levamisole in patients with node-positive colon cancer. This regimen is fairly well tolerated and devoid of long-term sequelae, and is now considered standard treatment for node-positive colon cancer. One trial showed a modest improvement in disease-free survival for the semustine/vincristine/5-FU combination; the leukemogenicity and renal toxicity caused by semustine have prevented this regimen from being adopted. Although administering 5-FU directly into the portal vein may improve disease-free survival, most trials have failed to demonstrate a reduction in the incidence of hepatic metastases. This technique, therefore, remains investigational. Several trials in rectal cancer show an advantage for 5-FU combined with semustine and radiation therapy in terms of disease-free survival, overall survival, or both; the contribution of semustine has been questioned and is currently being investigated. In patients with metastatic disease, hepatic arterial infusion of floxuridine produces a higher objective response rate than intravenous administration, but has not resulted in a survival benefit; hepatobiliary toxicity limits the duration of therapy. Biochemical modulation of 5-FU with leucovorin increases the response rate produced by 5-FU alone; a survival benefit has also been observed. N-(phosphonacetyl)-L-aspartate has shown initial promise in combination with high-dose 5-FU infusions. Among the many new drugs tested, only tauromustine seems worthy of further study.
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PMID:Current treatment approaches in colorectal cancer. 199 27

Novel immunotherapeutic strategies for combating colon cancer are also being explored in pancreatic, hepatic, and esophageal cancers. Preliminary clinical trials in patients with pancreatic cancer suggest a therapeutic role for anti-idiotypic antibodies against tumor-specific monoclonal antibodies (MoAbs)--eg, CO17-1A, BW 494/32--but not for MoAbs when used alone. Adding low doses of interferon gamma to CO17-1A enhances in vitro antibody-dependent cellular cytotoxicity against pancreatic tumor cells; CO17-1A plus a regimen of 5-FU/doxorubicin/mitomycin has resulted in beneficial therapeutic effect. Treatments with immunotoxins, radiolabeled MoAbs, and adoptive immunotherapy are still being tested preclinically. In 105 patients with unresectable hepatocellular cancer, a 7% complete and 41% partial regression rate with 131I-labeled antiferritin has been reported. In several patients, radiolabeled antiferritin caused sufficient shrinkage of lesions to permit curative resection. Pretreatment with low-dose doxorubicin may improve the efficacy of low-dose radiolabeled antiferritin antibody therapy. Chemoembolization of primary hepatocellular carcinoma, based on the concept of regional therapy for metastatic colorectal cancer, has shown considerable palliative and survival benefit in patients with unresectable disease. Although adoptive immunotherapy has been used to treat hepatocellular carcinoma, the results have been disappointing. The development of immunotherapeutic approaches to esophageal cancer is less advanced than that for other gastrointestinal malignancies. Paralleling the successful use of 5-FU/interferon alfa-2a in colon cancer are two phase II studies that have evaluated this combination in patients with locally advanced esophageal cancer. The objective response rate (27%) was encouraging.
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PMID:Implications of current therapeutic approaches in colorectal cancer for other gastrointestinal malignancies. 199 29

The prognosis of colon cancer, after curative resection, is mainly related to the outcome of metastases, and especially of liver metastases. It is generally accepted that adjuvant medical therapy is important in order to prevent the incidence of metastatic recurrences. The aim of the present review is to analyse the conclusions of the main recent randomized trials assessing the comparative value of different adjuvant protocols. The results obtained using either systemic infusion, the classical one, or intraportal infusion, which is mainly designed to prevent liver metastases, are reported. On the basis of the review, we can conclude that: adjuvant chemotherapy using combined drugs (MF, MOF) 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 tumour. According to a unique and limited trial, intraportal adjuvant therapy has been shown to be effective for patients with Dukes B tumours, but this remains to be confirmed. On the basis of the present data, new adjuvant programs using combined chemotherapeutic and immunotherapeutic coupounds, and combined systemic and loco-regional infusion, could be developed.
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PMID:[Prevention of hepatic metastases in radically operated colonic cancers]. 206 93


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