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 has shown activity in advanced colorectal cancer resistant to leucovorin and fluorouracil. Preclinical experiments on cell cultures and human tumor xenografts indicated potential synergy when combining irinotecan and fluorouracil. We designed a new regimen combining leucovorin, fluorouracil, irinotecan, and hydroxyurea (FOLFIRI-2) and conducted a phase II study to establish its efficacy and tolerance in advanced colorectal cancer refractory to fluorouracil and oxaliplatin. Treatment was repeated every 2 weeks and consisted of leucovorin 400 mg/m2 on day 1, immediately followed by 46 hours of continuous infusion of fluorouracil 2,000 mg/m2, irinotecan 180 mg/m2 on day 3, and hydroxyurea 1,500 mg the day before leucovorin, and on days 1 and 2. Treatment was continued until progression or limiting toxicity. Twenty-nine heavily pretreated patients entered the study. Five patients achieved an objective response (17%), and 12 obtained stabilization of disease or minor response (52%). Five patients failed to continue treatment (17%) because of toxicity or worsening condition. From the start of FOLFIRI-2 treatment, median progression-free survival was 4.1 months and median survival was 9.7 months. Grade III/IV National Cancer Institute-Common Toxicity Criteria toxicities were nausea 17%, diarrhea 31%, mucositis 14%, neutropenia 52%, and febrile neutropenia 14%. FOLFIRI-2 achieved a good rate of response and stabilization in heavily pretreated patients despite significant toxicity.
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PMID:Bimonthly leucovorin, infusion 5-fluorouracil, hydroxyurea, and irinotecan (FOLFIRI-2) for pretreated metastatic colorectal cancer. 1279 95

Radiation therapy has traditionally been the treatment of choice for locally or regionally advanced cancer, but its therapeutic efficacy is often hindered by limited tolerance of normal tissues and by tumor radioresistance. To improve therapeutic outcome, radiotherapy is frequently combined with chemotherapeutic drugs that are themselves cytotoxic and may sensitize cells to radiation. Solid evidence exists that administering standard chemotherapeutic agents during the course of radiotherapy (concurrent chemoradiotherapy) increases both local tumor control and patient survival in a number of cancer sites. These therapeutic improvements, however, have been achieved at the expense of considerable normal tissue toxicity. To improve chemoradiotherapy further, there have been extensive explorations of the potential of newer chemotherapeutic agents, including irinotecan (CPT-11, Camptosar) and other topoisomerase inhibitors. Preclinical studies have shown that these agents are potent radiosensitizers, providing a strong biologic rationale for using these drugs in combination with radiotherapy. These studies also generated information critical for designing effective treatment schedules in clinical settings. The therapeutic efficacy of topoisomerase inhibitor-radiation combinations is currently being tested clinically. Recent advances in molecular biology have discovered many cellular molecules, including the cyclooxygenase-2 (COX-2) enzyme, that promote tumor cell survival and are responsible for tumor resistance to cytotoxic agents, and hence may serve as potential targets for augmentation of radio (or chemo) response. COX-2 is often overexpressed in premalignant lesions and cancer, and is involved in carcinogenesis, tumor growth, and metastatic spread. Preclinical studies provided solid evidence that inhibition of this enzyme with selective COX-2 inhibitors prevents carcinogenesis, slows the growth of established tumors, and enhances tumor response to radiation without appreciably affecting normal tissue radioresponse. The mechanisms of enhancement of tumor radioresponse involve direct actions on tumor cells and indirect actions, primarily on tumor vasculature. COX-2 inhibitors also improve tumor response to chemotherapeutic agents, including irinotecan. Additional therapeutic benefit was observed for celecoxib (Celebrex), a selective COX-2 inhibitor, consisting of a strong reduction in irinotecan-induced diarrhea. Thus, selective targeting of COX-2 may potentially improve radiotherapy, chemotherapy, or chemoradiotherapy--a therapeutic strategy that is currently being tested in clinical trials.
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PMID:Improvement of radiotherapy or chemoradiotherapy by targeting COX-2 enzyme. 1280 Jun 1

A phase I study of carboplatin (Paraplatin) administered in two different dosing schedules (single dose every 4 weeks and weekly dosing) in combination with weekly irinotecan (CPT-11, Camptosar) was conducted in patients with relapsed or refractory advanced malignancies. Fifty-three patients with a variety of tumor types were randomly enrolled on the two different treatment regimens and have received a total of 163 cycles of treatment to date. Twenty-six patients received weekly irinotecan in combination with a single fixed dose of every-4-week carboplatin (arm 1). Initially, patients received irinotecan on days 1, 8, and 15, in combination with fixed-dose carboplatin at an area under the concentration-time curve (AUC) of 5.5 (Calvert formula) on day 1 every 28 days. Due to dose-limiting toxicities encountered at the first two dose levels, the protocol was amended to decrease the fixed dose of carboplatin to an AUC of 4.0 every 4 weeks. Dose-limiting toxicity was again encountered, so the day-15 dose of irinotecan was eliminated from the dosing regimen. The recommended phase II dose for heavily pretreated patients is irinotecan at 60 mg/m2 on days 1 and 8 in combination with carboplatin at AUC 4.0 on day 1 with cycles repeated every 28 days. Twenty-seven patients were treated with weekly irinotecan in combination with fixed-dose weekly carboplatin (arm 2). The initial dosing regimen consisted of irinotecan in combination with fixed-dose carboplatin at an AUC of 1.8 on days 1, 8, and 15, with treatment cycles repeated every 28 days. Due to the development of dose-limiting toxicities at the first two dose levels, the dosing regimen was subsequently amended to weekly irinotecan in combination with fixed-dose carboplatin at AUC 2.0 on days 1 and 8 only, and the dosing interval was shortened to every 21 days. With this amended regimen, the recommended phase II doses are irinotecan at 90 mg/m2 in combination with carboplatin at AUC 2.0 on days 1 and 8, with treatment cycles repeated every 21 days.
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PMID:Phase I. Trial of irinotecan plus carboplatin in two dose schedules. 1280 Jun 5

Camptothecin-based drugs, because of their poor solubility and labile lactone ring, pose challenges for drug delivery. The purpose of this research was to develop a nanoparticle delivery system for camptotheca alkaloids. After initial investigations SN-38 was selected as the candidate camptotheca alkaloid for further development. Nanoparticles comprising SN-38, phospholipids and polyethylene glycol were developed and studied in vitro and in vivo. The SN-38 formulations were stable in human serum albumin and high lactone concentrations were observed even after 3 h. In vivo studies in nude mice showed prolonged half-life of the active (lactone form) drug in whole blood and increased efficacy compared to Camptosar in a mouse xenograft tumor model.
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PMID:Nanoparticle drug delivery system for intravenous delivery of topoisomerase inhibitors. 1293 48

Local-regional carcinoma of the esophagus is often diagnosed in advanced stages because the diagnosis is established when symptoms are severe. The prognosis of patients with local-regional carcinoma of the esophagus continues to be grim. While preoperative chemoradiotherapy increases the fraction of patients who achieve pathologic complete response, that percentage is approximately 25%. In an attempt to increase the number of patients with either no cancer in the surgical specimen or only microscopic cancer, we adopted a three-step strategy. The current study utilized up to two 6-week cycles of induction chemotherapy with irinotecan (CPT-11, Camptosar) and cisplatin as step 1. This was followed by concurrent radiotherapy and chemotherapy with continuous infusion fluorouracil (5-FU) and paclitaxel as step 2. Once the patients recovered from chemoradiotherapy, a preoperative evaluation was performed and surgery was attempted. All patients signed an informed consent prior to their participation on the study. A total of 43 patients were enrolled. The baseline endoscopic ultrasonography revealed that 36 patients had a T3 tumor, five patients had a T2 tumor, and two had a T1 tumor. Twenty-seven patients had node-positive cancer (N1). Thirty-nine (91%) of the 43 patients underwent surgery; all had an R0 (curative) resection. A pathologic complete response was noted in 12 of the 39 patients. In addition, 17 patients had only microscopic (< 10%) viable cancer in the specimen. Therefore, a significant pathologic response was seen in 29 (74%) of 39 taken to surgery or 29 (67%) of all 43 patients enrolled on the study. With a median follow up beyond 25 months, 20 patients remain alive and 12 patients remain free of cancer. Our preliminary data suggest that the proportion of patients with significant pathologic response can be increased by using the three-step strategy.
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PMID:Irinotecan/cisplatin followed by 5-FU/paclitaxel/radiotherapy and surgery in esophageal cancer. 1456 43

Irinotecan (CPT-11, Camptosar) is one of the new generation of chemotherapeutic agents that has activity in advanced colorectal cancer. It has antitumor efficacy as a single agent, and also has been combined with fluorouracil (5-FU) and leucovorin (IFL) to treat these patients. Randomized studies have confirmed the superiority of IFL to 5-FU and leucovorin alone with regard to patient survival, time to progression, and tumor response rate. The optimal schedule for combining these agents remains uncertain, but in the United States, the schedule of IFL weekly for 4 consecutive weeks repeated every 6 weeks, according to the schedule reported by Saltz et al, has been widely used, although with some toxicity (especially myelosuppression and diarrhea). In an attempt to improve the tolerability of IFL, some have advocated modifying the schedule of IFL to weekly for 2 weeks, with repeated cycles every 21 days. Twenty-three patients with advanced colorectal cancer have been treated on this schedule at a single institution. Therapy was well tolerated, with 35% of patients experiencing grade 3/4 neutropenia, two of whom had episodes of febrile neutropenia, and 9% with grade 3/4 diarrhea. The median relative dose intensity of irinotecan administered in the first 18 patients treated with this regimen was 94%. These data support the hypothesis that modifying the schedule of administration of IFL improves the tolerability and ability to deliver the regimen, but must be confirmed by randomized prospective studies, which may also attempt to evaluate the role of bolus 5-FU in the treatment of advanced colorectal cancer.
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PMID:Improving the toxicity of irinotecan/5-FU/leucovorin: a 21-day schedule. 1456 47

Small bowel adenocarcinoma (SBA) is a relatively rare disease. Because of its rarity the role of chemotherapy either as adjuvant or for advanced disease has not been clearly defined. Therefore any information, including case reports, is warranted. We report on three patients with adenocarcinoma of the jejunum and ileum. Two patients with positive lymph nodes received postoperative adjuvant chemotherapy with 5-fluorouracil-folinic acid (5FU-FA) for 12 months but they developed metastatic disease 3 and 8 months later, respectively. The third patient was initially treated with the same agents but for metastatic disease. All patients were subsequently treated for tumor recurrence with irinotecan 350 mg/m2 i.v. every 3 weeks as salvage chemotherapy supported by Granulocyte Colony Stimulating Factor (GCSF) for 5 days. Two patients achieved a minor response and had a dramatic improvement of their symptoms. Their survival times after irinotecan administration were 14 and 6 months with an overall survival after primary diagnosis of 29 and 27 months, respectively. The third patient who had a tumor refractory to 5FU-FA progressed also on irinotecan and had an 8-month overall survival. Although conclusions cannot be drawn regarding the role of adjuvant chemotherapy in SBA, it seems reasonable to extrapolate from large bowel carcinoma experience. Irinotecan seems to have some degree of activity in the treatment of SBA but further studies are warranted.
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PMID:Irinotecan as salvage chemotherapy for advanced small bowel adenocarcinoma: a series of three patients. 1459 44

SN-38, 7-ethyl-10-hydroxycamptothecin, is the active metabolite of Irinotecan (CPT-11), a topoisomerase I inhibitor commercially available as Camptosar. SN-38 is approximately 200-2000-fold more cytotoxic than CPT-11. Despite its promising anticancer potential, SN-38 thus far has not been used as an anticancer drug due to its poor solubility in any pharmaceutically acceptable solvents. In addition, SN-38 has low affinity to lipid membranes; it tends to precipitate in aqueous phase resulting in a very low drug-to-liposome entrapment. SN-38 also reversibly converts to an inactive open lactone ring structure at physiological pH. We have developed a novel, liposome-based SN-38 formulation (LE-SN-38). The formulation contains liposomes of uniform size distribution (<200nm), and it is easy-to-use. Drug entrapment efficiency of the formulation is >95%. Long-term stability studies indicate that the lyophilized LE-SN-38 is physically and chemically stable for at least 6 months at 2-8 degrees C. In preclinical studies, LE-SN38 has shown promising results in terms of increased cytotoxicity against various tumor cell lines and better therapeutic efficacy towards xenograft mouse models compared to CPT-11.
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PMID:Development and characterization of a novel liposome-based formulation of SN-38. 1472 26

Mutations in the tumor-suppressor gene p53 have been associated with advanced colorectal cancer (CRC). Irinotecan (CPT-11), a DNA topoisomerase 1 inhibitor, has been recently incorporated to the adjuvant therapy. Since the DNA-damage checkpoint depends on p53 activation, the status of p53 might critically influence the response to CPT-11. We analysed the sensitivity to CPT-11 in the human colon cancer cell line HT29 (mut p53) and its wild-type (wt)-p53 stably transfected subclone HT29-A4. Cell-cycle analysis in synchronised cells demonstrated the activation of transfected wt-p53 and a p21(WAF1/CIP1)-dependent cell-cycle blockage in the S phase. Activated wt-p53 increased apoptosis and enhanced sensitivity to CPT-11. In p53-deficient cells, cDNA-macroarray analysis and western blotting showed an accumulation of the cyclin-dependent kinase (cdk)1/cyclin B complex. Subsequent p53-independent activation of the cdk-inhibitor (cdk-I) p21(WAF1/CIP1) prevented cell-cycle progression. Cdk1 induction was exploited in vivo to improve the sensitivity to CPT-11 by additional treatment with the cdk-I CYC-202. We demonstrate a gain of sensitivity to CPT-11 in a p53-mutated colon cancer model either by restoring wild-type p53 function or by sequential treatment with cdk-Is. Considering that mutations in p53 are among the most common genetic alterations in CRC, a therapeutic approach specifically targeting p53-deficient tumors could greatly improve the treatment outcomes.
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PMID:Enhanced sensitivity to irinotecan by Cdk1 inhibition in the p53-deficient HT29 human colon cancer cell line. 1500 86

Irinotecan has proven anti-tumor activity as induction treatment in combination with 5-fluorouracil (5-FU) or as second-line treatment after 5-FU in patients with metastatic colorectal cancer. The aim of the present phase II study was to evaluate irinotecan as third-line chemotherapy in patients with colorectal cancer after sequential treatment with bolus 5-FU followed by an infusional 5-FU regimen. Patients pretreated with bolus 5-FU/folinic acid and the infusional 5-FU/folinic acid regimen were treated with 350 mg/m irinotecan i.v. once every 3 weeks in a multicenter phase II study. Tumor size was measured every cycle and treatment with irinotecan was continued until the occurrence of progressive disease or unacceptable toxicity. A total of 50 pretreated patients were included. Of the 45 evaluable patients, 13.3% [n=6, 95% confidence interval (CI) 5.1-26.8] attained a response (complete/partial response) to treatment lasting 5.6 months (95% CI 4.2-6.3) and in four patients response has been confirmed (8.9%, 95% CI 2.5-21.2). Disease stabilization was noted in 51.1% of the patients (n=23, 95% CI 35.8-66.3). The median duration of response/disease stabilization was 4.2 months (95% CI 3.2-6.0). Median overall survival was 7.9 months (95% CI 6.1-11.1), corresponding to a calculated 1-year survival of 28.3% (95% CI 15.2-41.3). Severe neutropenia occurred in 14% (n=7) and anemia grade III in 6% of the patients (n=3). The most frequent non-hematological toxicity grade III/IV related to treatment was diarrhea in 24% of the patients (n=12), followed by vomiting in 8% (n=4) and constipation as well as infection in two patients each (4%) (evaluable n=50). We conclude single-agent irinotecan is an effective and well-tolerable treatment in pretreated patients with metastatic colorectal cancer after failure of bolus and infusional 5-FU/folinic acid regimens. Elderly patients had the same probability to respond.
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PMID:Prospective multicenter phase II study of irinotecan as third-line therapy in metastatic colorectal cancer and progression after bolus and infusional 5-fluorouracil. 1516 21


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