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)

Irinotecan and its active metabolite, SN-38, were reported to have the absorption characteristics of weakly basic drugs. Moreover, stasis of these compounds is thought to induce damage to the intestinal mucous membrane. The purpose of this report was to examine whether oral alkalization (OA) combined with control of defecation (CD) might prevent irinotecan-induced side effects. From day one of irinotecan infusion to day four, OA & CD were practiced using orally administered sodium bicarbonate, magnesium oxide, basic water, and ursodeoxycholic acid. Thirty-two lung cancer patients were treated with irinotecan in combination with cisplatin in the absence of OA & CD (Group A). Thirty-seven patients matched for background characteristics were treated with the same regimen in the presence of OA & CD (Group B). Group B had a reduced incidence of delayed diarrhea (Grade 2 < or = Group A 32.3% vs. Group B 9.4%), nausea, vomiting, and myelotoxicity, especially granulocytopenia compared with Group A. In addition, dose intensification was well-tolerated in Group B. Tumor response rates for non-small cell lung cancer were 59.3% (16/27 patients) in Group B against 38.5% (10/26 patients) in Group A. OA & CD appears to reduce the irinotecan-induced side effects, especially delayed diarrhea. Risk factors statistically associated with delayed diarrhea include advanced age and the use of irinotecan without OA & CD.
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PMID:[A case-control study of prevention of irinotecan-induced diarrhea: the reducing side effects of irinotecan by oral alkalization combined with control of defecation]. 1214 98

The prodrug irinotecan is an active agent for the treatment of advanced colorectal cancer and a number of other solid tumors. Irinotecan is converted in vivo to SN-38 (7-ethyl-10-hydroxy-camptothecin), the active metabolite that causes cell death, by human liver carboxylesterases. Previous studies suggest that human carboxylesterase 2 (CES2) is the key activating isoform. Although conversion of irinotecan to SN-38 by liver carboxylesterase is an inefficient process, clinical data indicate that irinotecan has significant antitumor activity. This scenario raises the possibility that local conversion of irinotecan to SN-38 by CES2 in tumor tissues might occur. The expression profile of CES2 protein in human tumor tissues was evaluated in a tissue array of 18 different types of human cancer and in a panel of normal human liver samples by immunohistochemistry and Western blot, respectively. Cytosolic CES2 expression was observed in 101 of 154 tumors (66%) and 55 of 60 normal tissues (92%). Among the 18 types of tumors analyzed, 2 types (gallbladder tumor and lymphoma) did not express CES2, 5 types expressed weak CES2, and 11 types expressed moderate to intense CES2. In functional studies, CES2 protein was highly variable among liver samples, with a 15-fold range in cytosol and a 3-fold range in microsome fractions. Liver microsomal CES2 protein expression was significantly correlated with irinotecan activation to SN-38 (R(s) = 0.70; P = 0.007). This study confirms that CES2 is a key enzyme for irinotecan activation. Tumor CES2 expression may contribute to variable response to irinotecan chemotherapy for solid tumors.
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PMID:Human carboxylesterase 2 is commonly expressed in tumor tissue and is correlated with activation of irinotecan. 1217 91

Irinotecan and mitomycin (Mutamycin) possess significant single-agent activity against several tumor types, and mitomycin activates topoisomerase I, the cellular target of irinotecan. We conducted a phase I dose-escalation study of irinotecan and mitomycin in 37 evaluable patients with solid tumors. Antitumor responses included 2 complete responses, 5 partial responses, 10 minor responses, and a CA 19-9 tumor marker response. Responders included 14 patients previously treated with chemotherapy for metastatic disease. No pharmacokinetic interaction between mitomycin and irinotecan was apparent when these agents were given 24 hours apart. Responders (complete and partial responses) demonstrated the largest topoisomerase I induction 24 hours following mitomycin infusion. In addition, since maximum topoisomerase I up-regulation was reached 24 hours after administration of mitomycin, a delay in the administration of irinotecan after mitomycin appeared justified. Based on these encouraging phase I data, phase II clinical trials in breast and esophageal/gastroesophageal junction adenocarcinomas at the recommended doses and schedule are under way.
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PMID:Mitomycin as a modulator of irinotecan anticancer activity. 1219 29

Irinotecan (CPT-11), a recently introduced component of a standard chemotherapy for colorectal cancer, induces in colon cancer cell lines in vitro cell cycle arrest and apoptosis. Since sporadic colon carcinomas exhibit in 50-60% mutations in the p53 gene and in 10-15% an MSI phenotype due in the great majority of the cases to hMLH1 inactivation, we investigated how these lesions influence the cellular effects of CPT-11 by using colorectal carcinoma cell line HCT116 (which has the genotype p53(+/+),hMLH1(-)) and 2 derivative cell lines with the genotypes p53(+/+),hMLH1(+) and p53(-/-),hMLH1(-). CPT-11 treatment induced G2/M arrest in all 3 cell lines within 48 hr. In the p53(+/+),hMLH1(+) cell line, G2/M arrest was maintained for at least 12 days. There was little concomitant apoptosis, but this was enhanced when the hMLH1 protein was absent. This enhanced apoptosis was accompanied by a shorter duration of the G2/M arrest than in the hMLH1(+) cell line. Partial abrogation of G2/M arrest by caffeine enhanced apoptosis in both hMLH1(+) and hMLH1(-) cells. By contrast, in the p53(-/-) cell line, the G2/M arrest was terminated within 4 days. Termination of the G2/M arrest was accompanied by a high level of apoptosis detectable through poly(ADP-ribose)polymerase (PARP) cleavage, DNA fragmentation and by the appearance of cells with a DNA content <2N. The triggering of G2/M arrest was accompanied in the 3 cell lines by a transient phosphorylation of cdc-2, while the maintenance of the arrest in the p53(+/+) cell lines was accompanied by the overexpression of p53 and p21 proteins and, consequently, by the inhibition of cdc-2 kinase activity. These data indicate that: (i) CPT-11 induces long-term arrest in p53(+/+) cells and a short-term arrest followed by apoptosis in p53(-/-) cells; (ii) triggering of the arrest is p53 independent and is associated with a brief increase of phosphorylation of cdc-2, while the p53-dependent maintenance of G2/M arrest is associated with the inhibition of cdc-2 kinase activity by p21; and (iii) lack of hMLH1 protein enhances CPT-11-induced apoptosis. These results may be useful for designing rational therapies dependent on the p53 and mismatch-repair status in the tumor.
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PMID:Cellular effects of CPT-11 on colon carcinoma cells: dependence on p53 and hMLH1 status. 1220 84

Combining anticancer drugs with different mechanisms of action has the potential to enhance antitumor effect. CPT-11 (Camptosar, irinotecan), a topoisomerase I inhibitor, has been shown to be highly effective in the treatment of a variety of cancers. However, its clinical usage is often complicated by late diarrhea. A number of studies have shown that cyclooxygenase (COX)-2 is overexpressed in many forms of human tumors, suggesting that COX-2 inhibition may be useful in the treatment of cancer. In this study, we used two mouse tumor models (HT-29 and colon-26 cells) to evaluate the effect of combining CPT-11 with celecoxib on tumor growth. We also assessed the involvement of COX-2 in the pathogenesis of CPT-11-induced late diarrhea using a rat model. Results indicate that celecoxib enhances the antitumor effect of CPT-11 and reduces the severity of late diarrhea in a dose-dependent manner. The extended benefits of combining celecoxib with CPT-11 may significantly improve the outcome of cancer patients.
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PMID:Cyclooxygenase-2 inhibition with celecoxib enhances antitumor efficacy and reduces diarrhea side effect of CPT-11. 1238 38

Hepatoblastoma is the most common liver tumor diagnosed in children. Children with persistently unresectable disease, metastatic disease at presentation, recurrent disease, or slowly declining alpha-fetoprotein levels are at high risk for recurrence, exhibit an extremely poor prognosis, and are in desperate need of novel therapeutic agents and strategies. Four high-risk patients were treated. One patient with a local recurrence was treated with irinotecan followed by orthotopic liver transplant. Three patients were treated with tandem high-dose chemotherapy (HDT) with autologous stem cell rescue (two with primary metastatic disease and one with recurrent disease). All three of the patients treated with HDT had relapse (two of them subsequently received irinotecan); the remaining patient underwent surgical resection of a solitary recurrent pulmonary metastasis. Irinotecan demonstrated significant antitumor effects in all three treated patients and was well tolerated. None of the three patients treated with HDT remained disease-free, although the patient who underwent surgical resection of a solitary recurrent pulmonary metastasis remains disease-free 6 years from diagnosis. Further exploration of the use of irinotecan is warranted in high-risk patients with hepatoblastoma.
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PMID:Novel therapeutic approaches in the treatment of children with hepatoblastoma. 1246 18

Capecitabine (Xeloda) and irinotecan (CPT-11, Camptosar) exhibit single-agent activity in colorectal cancer, have nonoverlapping major toxicities, and exhibit a synergistic effect in tumor xenograft models. European early-phase trials of the combination in patients with metastatic colorectal cancer indicate good response rates across doses tested and manageable toxicities, with available data supporting use of a regimen of oral capecitabine at 1,000 mg/m2 twice daily on days 1 to 14 plus IV irinotecan at 250 mg/m2 on day 1 every 21 days in this setting. The European Organisation for Research and Treatment of Cancer has planned a phase III trial (EORTC 40015) comparing this regimen of capecitabine/irinotecan with infusional fluorouracil (5-FU)/leucovorin plus irinotecan in approximately 700 patients with metastatic colorectal cancer. The QUASAR (Quick and Simple and Reliable) 2 adjuvant trial will compare 5-FU/leucovorin with capecitabine/irinotecan given over 6 months as adjuvant therapy in patients with stage II/III colorectal cancer. These trials will help define the roles of this combination in the treatment of colorectal cancer.
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PMID:Capecitabine/irinotecan in colorectal cancer: European early-phase data and planned trials. 1252 Jun 34

Esophageal cancer is uncommon, but its incidence is rapidly increasing in the Western countries because of the high incidence of the cardia esophageal adenocarcinoma. Notwithstanding the encouraging results achieved with surgical procedures, esophageal carcinoma has a poor prognosis with 5-year survival in 10% of cases without differences between both squamous and adenocarcinoma histologies. Almost 50% of esophageal cancer patients have unresectable disease at presentation; in the past years combined modality treatments, using chemotherapy and/or radiotherapy with or without surgery, have been evaluated to reduce the risk of local and/or distant recurrences. Ongoing regimens with new agents (Taxanes, Vinorelbine, Irinotecan), in association or not with platinum compounds, show good antitumor efficacy and tolerability, even in the metastatic disease. Preoperative strategies with radiation only did not give any advantage compared to surgery alone, instead, controversial results were obtained, with a minimal advantage, using chemotherapy. Combined chemotherapy and radiation, in suitable candidates for resection has shown an improvement of complete pathological responses, in both the histologies, but with superior toxicities when compared to chemotherapy or radiation therapy alone. Postoperative adjuvant therapies as radiation, chemotherapy or both, have not led to a marked improvement in overall survival and should be performed only in clinical trials. The use of chemoradiotherapy showed a clear advantage versus radiotherapy alone and in many cases equivalent to regimens plus surgery even if control studies haven't been performed. Clinical trials with novel biologic agents, in combination to chemotherapy or alone, against cell growth arrest, neoagiongenesis and tumor metastasis invasion process are currently under evaluation. In the coming years new markers as antigen Ki-67 determination, p53 mutation or high levels activity of thymidylate synthase and novel staging techniques as PET could be precious to identify the better treatment for each patient.
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PMID:[New strategies in the treatment of esophageal cancer]. 1259 16

To perform a series of in vivo cytotoxicity studies using a variety of doses of the comptothecin analogues 9-Aminocamptothecin (9-AC) and Irinotecan (CPT-11) with a human RCC xenograft tumor line (DU11983m). Using the subrenal capsule assay (80 nude mice) (NM-SRCA), 9-AC was evaluated at both low and high dosage levels (0.75 mg/kg and 1.25 mg/kg oral x10 doses over 12 days). Following an initial assessment of acute tumor inhibition, the study was extended to a survival assay with some cohorts receiving retreatment boluses on a once or twice weekly basis. CPT-11 was assessed at a dose of 100 mg/kg x3 over 9 days with weekly retreatment and two cohorts received 9-AC combined with Vinblastine (2.7 mg/kg) and Vinblastine alone, respectively. Tumor inhibition: tumor growth inhibition was significant (over 80%) with all cohorts receiving any camptothecin analogue and was virtually complete (>99% tumor inhibition) at the high dose 9-AC (1.25 mg/kg). Vinblastine alone achieved only moderate cytotoxic effect (46%) and induced the largest recorded cohort weight loss (toxicity). Survival analysis: the low and high dose 9-AC single agent cohorts were not significantly different; however, the CPT-11 cohort experienced maximal survival benefit. (P = 0.003) and the addition of Vinblastine did not enhance this survival advantage among the 9-AC cohorts. Control and single agent Vinblastine cohorts had the poorest survival with the treated group still surviving longer (P = 0.02). At 35 days after final assessment of acute tumor inhibition, all animals in both the control and Vinblastine alone cohorts were dead. None of the animals in any of the other cohorts (all of which had experienced a greater than 80% tumor inhibition) had died. No deaths occurred due to surgery or treatment toxicity and all deaths were deemed tumor related. CPT-11 and 9-AC produced a marked survival advantage in an orthotopic model of human advanced renal carcinoma and are identified as agents for further clinical assessment.
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PMID:Camptothecin analogues and vinblastine in the treatment of renal cell carcinoma: an in vivo study using a human orthotopic renal cancer xenograft. 1268 28

Irinotecan is a water-soluble derivative of camptothecin, an alkylator originally extracted from the Chinese tree Camptotheca acuminata. Laboratory studies have demonstrated the activity of irinotecan in a broad panel of pediatric and adult central nervous system tumor xenografts in athymic nude mice. These studies led to a Phase II trial that confirmed the activity of this agent in the treatment of recurrent malignant glioma. Subsequent laboratory studies have demonstrated that a combination of irinotecan (CPT-11) and alkylating agents, particularly 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU), increases antitumor effects to a level well above the additive effects of the individual agents. These laboratory studies generated a recently completed Phase I trial of CPT-11 + BCNU, which now is being evaluated in a formal Phase II trial for adults with newly diagnosed or recurrent malignant glioma. More recent studies have demonstrated similar interaction between CPT-11 and temozolomide and have led to a Phase I trial of these agents in the treatment of adults with malignant glioma. Studies currently are addressing the role of O(6)-alkylguanine-DNA alkyltransferase (AGT) in reducing the benefits of combining CPT-11 with temozolomide and the potential therapeutic gain from utilizing an inhibitor of AGT.
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PMID:The emerging role of irinotecan (CPT-11) in the treatment of malignant glioma in brain tumors. 1271 57


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