987 resultados para 5-fluorouracil (5-FU)


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PURPOSE: We conducted a phase I/II clinical trial to determine the safety and feasibility of combining vorinostat with 5-fluorouracil (5-FU) in patients with metastatic colorectal cancer (mCRC) and elevated intratumoral thymidylate synthase (TS).

METHODS: Patients with mCRC who had failed all standard therapeutic options were eligible. Intratumoral TS mRNA expression and peripheral blood mononuclear cell (PBMC) histone acetylation were measured before and after 6 consecutive days of vorinostat treatment at 400 mg PO daily. 5-FU/LV were given on days 6 and 7 and repeated every 2 weeks, along with continuous daily vorinostat. Dose escalation occurred in cohorts of three to six patients.

RESULTS: Ten patients were enrolled. Three dose levels were explored in the phase I portion of the study. Two dose-limiting toxicities (DLTs) were observed at the starting dose level, which resulted in dose de-escalation to levels -1 and -2. Given the occurrence of two DLTs at each of the dose levels, we were unable to establish a maximum tolerated dose (MTD). Two patients achieved significant disease stabilization for 4 and 6 months. Grade 3 and 4 toxicities included fatigue, thrombocytopenia and mucositis. Intratumoral TS downregulation > or = 50% was observed in one patient only. Acetylation of histone 3 was observed in PBMCs following vorinostat treatment.

CONCLUSIONS: The study failed to establish a MTD and was terminated. The presence of PBMC histone acetylation indicates biological activity of vorinostat, however, consistent reductions in intratumoral TS mRNA were not observed. Alternate vorinostat dose-scheduling may alleviate the toxicity and achieve optimal TS downregulation.

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PURPOSE: The association of continuous infusion 5-fluorouracil, epirubicin (50 mg/m2 q 3 weeks) and a platinum compound (cisplatin or carboplatin) was found to be very active in patients with either locally advanced/inflammatory (LA/I) [1, 2] or large operable (LO) breast cancer (BC) [3]. The same rate of activity in terms of response rate (RR) and response duration was observed in LA/I BC patients when cisplatin was replaced by cyclophosphamide [4]. The dose of epirubicin was either 50 mg/m2 [ 1, 2, 3] or 60 mg/m2/cycle [4]. The main objective of this study was to determine the maximum tolerated dose (MTD) of epirubicin when given in combination with fixed doses of cyclophosphamide and infusional 5-fluorouracil (CEF-infu) as neoadjuvant therapy in patients with LO or LA/I BC for a maximum of 6 cycles. PATIENTS AND METHODS: Eligible patients had LO or LA/I BC, a performance status 0-1, adequate organ function and were <65 years old. Cyclophosphamide was administered at the dose of 400 mg/m2 day 1 and 8, q 4 weeks and infusional 5-fluorouracil 200 mg/m2/day was given day 1-28, q 4 weeks. Epirubicin was escalated from 30 to 45 and to 60 mg/m2 day 1 and 8; dose escalation was permitted if 0/3 or 1/6 patients experienced dose limiting toxicity (DLT) during the first 2 cycles of therapy. DLT for epirubicin was defined as febrile neutropenia, grade 4 neutropenia lasting for >7 days, grade 4 thrombocytopenia, or any non-haematological toxicity of CTC grade > or =3, excluding alopecia and plantar-palmar erythrodysesthesia (this toxicity was attributable to infusional 5-fluorouracil and was not considered a DLT of epirubicin). RESULTS: A total of 21 patients, median age 44 years (range 29-63) have been treated. 107 courses have been delivered, with a median number of 5 cycles per patient (range 4-6). DLTs on cycles I and 2 on level 1, 2, 3: grade 3 (G3) mucositis occurred in 1/10 patients treated at the third dose level. An interim analysis showed that G3 PPE occurred in 5/16 pts treated with the 28-day infusional 5-FU schedule at the 3 dose levels. The protocol was subsequently amended to limit the duration of infusional 5-fluorouracil infusion from 4 to 3 weeks. No G3 PPE was detected in 5 patients treated with this new schedule. CONCLUSIONS: This study establishes that epirubicin 60mg/m2 day 1 and 8, cyclophosphamide 400mg/m2 day 1 and 8 and infusional 5-fluorouracil 200 mg/m2/day day 1-21. q 4 weeks is the recommended dose level. Given the encouraging activity of this regimen (15/21 clinical responses) we have replaced infusional 5-fluorouracil by oral capecitabine in a recently activated study.

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BACKGROUND: Pancreatic adenocarcinoma is a lethal disease with 5-year survival of less than 5%. 5-fluorouracil (5-FU) is a principal first-line therapy, but treatment only extends survival modestly and is seldom curative. Drug resistance and disease recurrence is typical and there is a pressing need to overcome this. To investigate acquired 5-FU resistance in pancreatic adenocarcinoma, we established chemoresistant monoclonal cell lines from the Panc 03.27 cell line by long-term exposure to increasing doses of 5-FU.

RESULTS: 5-FU-resistant cell lines exhibited increased expression of markers associated with multidrug resistance explaining their reduced sensitivity to 5-FU. In addition, 5-FU-resistant cell lines showed alterations typical for an epithelial-to-mesenchymal transition (EMT), including upregulation of mesenchymal markers and increased invasiveness. Microarray analysis revealed the L1CAM pathway as one of the most upregulated pathways in the chemoresistant clones, and a significant upregulation of L1CAM was seen on the RNA and protein level. In pancreatic cancer, expression of L1CAM is associated with a chemoresistant and migratory phenotype. Using esiRNA targeting L1CAM, or by blocking the extracellular part of L1CAM with antibodies, we show that the increased invasiveness observed in the chemoresistant cells functionally depends on L1CAM. Using esiRNA targeting β-catenin and/or Slug, we demonstrate that in the chemoresistant cell lines, L1CAM expression depends on Slug rather than β-catenin.

CONCLUSION: Our findings establish Slug-induced L1CAM expression as a mediator of a chemoresistant and migratory phenotype in pancreatic adenocarcinoma cells.

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Recent evidence indicates a potential prognostic and predictive value for germline polymorphisms in genes involved in cell cycle control. We investigated the effect of cyclin D1 (CCND1) rs9344 G>A in stage II/III colon cancer patients and validated the findings in an independent study cohort. For evaluation and validation set, a total of 264 and 234 patients were included. Patients treated with 5-fluorouracil-based chemotherapy, carrying the CCND1 rs9344 A/A genotype had significantly decreased time-to-tumor recurrence (TTR) in univariate analysis and multivariate analysis (hazard ratio (HR) 2.47; 95% confidence interval (CI) 1.16-5.29; P=0.019). There was no significant association between CCND1 rs9344 G>A and TTR in patients with curative surgery alone. In the validation set, the A allele of CCND1 rs9344 G>A remained significantly associated with decreased TTR in univariate and multivariate analyses (HR 1.94; 95% CI 1.05-3.58; P=0.035). CCND1 rs9344 G>A may be a predictive and/or prognostic biomarker in stage II/III colon cancer patients, however, prospective trials are warranted to confirm our findings.

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 Hollow mesoporous silica nanoparticles were successfully fabricated and functionalized with appropriate silanes. After modifications, amine, carboxyl, cyano, and methyl groups were grafted onto the nanoparticles and all functionalized hollow mesoporous silica nanoparticles maintained a spherical and hollow structure with a mean diameter of ~120 nm and a shell thickness of ~10 nm. The loading capacity of the hollow mesoporous silica nanoaprticles to the anticancer drug, 5-fluorouracil, can be controlled via precise functionalization. The presence of amine groups on the surface of nanoparticles resulted in the highest loading capacity of 28.89%, due to the amine functionalized nanoparticles having a similar hydrophilicity but reverse charge to the drug. In addition, the change in pH leads to the variation of the intensity of electrostatic force between nanoparticles and the drug, which finally affects the loading capacity of amine functionalized hollow mesoporous silica nanoparticles to some extent. Higher drug loading was observed at pH of 7.4 and 8.5 as 5-fluorouracil becomes more deprotonated in alkaline conditions. The improved drug loading capacity by amine functionalized hollow mesoporous silica nanoparticles has demonstrated that they can become potential intracellular 5-fluorouracil delivery vehicles for cancers.

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Acquired drug resistance (ADR) can be developed in colorectal cancer cells after 5-fluorouracil (5-FU) treatment and diminish the effectiveness of chemotherapy. In this work, acquired 5-FU resistance in the colorectal cancer cell line SW480 was obtained with the up-regulation of dihydropyrimidine dehydrogenase (DPYD) gene expression which can convert 5-FU to its inactive metabolite. To overcome ADR in colorectal cancer, hollow mesoporous silica nanoparticles (HMSNs) grafted with epidermal growth factor (EGF) were used as nanocarriers to deliver 5-FU to colorectal cancer cells with acquired drug resistance. The effect and mechanism of 5-FU loaded EGF grafted HMSNs (EGF-HMSNs-5-FU) in overcoming acquired drug resistance in SW480/ADR cells were studied. The EGF-HMSNs were demonstrated to be specifically internalized in EGFR overexpressed SW480/ADR cells via a receptor-mediated endocytosis and can escape from endo-lysosomes. The EGF-HMSNs-5-FU exhibited much higher cytotoxicity on SW480/ADR cells than HMSNs-5-FU and free 5-FU while the plain HMSNs did not show significant cytotoxicity. The mechanism of EGF-HMSNs-5-FU in overcoming drug resistance in SW480/ADR cells could be attributed to the specific internalization of EGF-HMSNs-5-FU in EGFR overexpressed cells which can lead to high intracellular drug accumulation and cause cell death through S phase arrest.

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• Aim: To observe the effects of topical application of 5-fluorouracil (5-FU) on the rabbits corneal limbus. • Methods: 5-FU was applied topically to the corneoscleral region of rabbits eyes. The animals were sacrificed immediately or 7, 15, 30 and 60 days later, and tissues were submitted to histological examination. • Results: All animals presented corneoscleral deepithelization close to the site of application during the immediate post-operative period, whereas on the 4th postoperative day ulceration was no longer present. Histological examination showed absence of epithelium and slight edema. After one week (G2), 2 animals presented epithelial defects, thickened epithelium with larger basal cells and loose chromatin, and slight subepithelial edema. The remaining groups showed no alterations. • Conclusion: The 5-FU topically on the corneoscleral limbus postpone the epitelization.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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AIM: The mTOR-inhibitor rapamycin has shown antitumor activity in various tumors. Bedside observations have suggested that rapamycin may be effective as a treatment for colorectal carcinomatosis. METHODS: We established an orthotopic syngenic model by transplanting CT26 peritoneal tumors in Balb/C mice and an orthotopic xenograft model by transplanting SW620 peritoneal tumors in nu/nu mice. Expression levels of tissue inhibitor of matrix-metalloproteinases 1 (TIMP-1) in the tumor and serum was determined by enzyme-linked immunosorbent assay. RESULTS: Rapamycin significantly suppressed growth of syngenic and xenografted peritoneal tumors. The effect was similar with intraperitoneal or oral rapamycin administration. Tumor suppression was further enhanced when rapamycin was combined with 5-fluorouracil and/or oxaliplatin. The combination treatment showed no acute toxicity. TIMP-1 serum levels correlated well (CC = 0.75; P < 0.01) with rapamycin treatment. CONCLUSIONS: Rapamycin suppressed advanced stage colorectal cancer, even with oral administration. Combining rapamycin with current chemotherapy regimens significantly increased antitumor efficacy without apparent toxicity. The treatment efficacy correlated with serum TIMP-1 levels, suggesting its potential as a surrogate marker in future clinical trials.

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POLYSACCHARIDES; ANTICOAGULANT; SURVIVAL

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Background:

COIN compared first-line continuous chemotherapy with the same chemotherapy given intermittently or with cetuximab in advanced colorectal cancer (aCRC).


Methods:

Choice between oxaliplatin/capecitabine (OxCap) and oxaliplatin/leucovorin (LV)/infusional 5-FU (OxFU) was by physician and patient choice and switching regimen was allowed. We compared OxCap with OxFU and OxCap+cetuximab with OxFU+cetuximab retrospectively in patients and examined efficacy, toxicity profiles and the effect of mild renal impairment.


Results:

In total, 64% of 2397 patients received OxCap(±cetuximab). Overall survival, progression free survival and overall response rate were similar between OxCap and OxFU but rate of radical surgeries was higher for OxFU. Progression free survival was longer for OxFU+cetuximab compared with OxCap+cetuximab but other efficacy measures were similar. Oxaliplatin/LV/infusional 5-FU (±cetuximab) was associated with more mucositis and infection whereas OxCap(±cetuximab) caused more gastrointestinal toxicities and palmar-plantar erythema. In total, 118 patients switched regimen, mainly due to toxicity; only 16% came off their second regimen due to intolerance. Patients with creatinine clearance (CrCl) 50–80?ml?min-1 on OxCap(±cetuximab) or OxFU+cetuximab had more dose modifications than those with better renal function.


Conclusions:

Overall, OxFU and OxCap are equally effective in treating aCRC. However, the toxicity profiles differ and switching from one regimen to the other for poor tolerance is a reasonable option. Patients with CrCl 50–80?ml?min-1 on both regimens require close toxicity monitoring.