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Sarkar S, Kiren S, Gmeiner WH. Review of Prodrug and Nanodelivery Strategies to Improve the Treatment of Colorectal Cancer with Fluoropyrimidine Drugs. Pharmaceutics 2024; 16:734. [PMID: 38931855 PMCID: PMC11206923 DOI: 10.3390/pharmaceutics16060734] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2024] [Revised: 05/24/2024] [Accepted: 05/24/2024] [Indexed: 06/28/2024] Open
Abstract
Fluoropyrimidine (FP) drugs are central components of combination chemotherapy regimens for the treatment of colorectal cancer (CRC). FP-based chemotherapy has improved survival outcomes over the last several decades with much of the therapeutic benefit derived from the optimization of dose and delivery. To provide further advances in therapeutic efficacy, next-generation prodrugs and nanodelivery systems for FPs are being developed. This review focuses on recent innovative nanodelivery approaches for FP drugs that display therapeutic promise. We summarize established, clinically useful FP prodrug strategies, including capecitabine, which exploit tumor-specific enzyme expression for optimal anticancer activity. We then describe the use of FP DNA-based polymers (e.g., CF10) for the delivery of activated FP nucleotides as a nanodelivery approach with proven activity in pre-clinical models and with clinical potential. Multiple nanodelivery systems for FP delivery show promise in CRC pre-clinical models and we review advances in albumin-mediated FP delivery, the development of mesoporous silica nanoparticles, emulsion-based nanoparticles, metal nanoparticles, hydrogel-based delivery, and liposomes and lipid nanoparticles that display particular promise for therapeutic development. Nanodelivery of FPs is anticipated to impact CRC treatment in the coming years and to improve survival for cancer patients.
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Affiliation(s)
- Santu Sarkar
- Department of Cancer Biology, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA;
| | - Sezgin Kiren
- Department of Chemistry, Winston-Salem State University, Winston-Salem, NC 27110, USA;
| | - William H. Gmeiner
- Department of Cancer Biology, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA;
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2
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Gmeiner WH, Okechukwu CC. Review of 5-FU resistance mechanisms in colorectal cancer: clinical significance of attenuated on-target effects. CANCER DRUG RESISTANCE (ALHAMBRA, CALIF.) 2023; 6:257-272. [PMID: 37457133 PMCID: PMC10344727 DOI: 10.20517/cdr.2022.136] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 04/01/2023] [Accepted: 04/17/2023] [Indexed: 07/18/2023]
Abstract
The emergence of chemoresistant disease during chemotherapy with 5-Fluorouracil-based (5-FU-based) regimens is an important factor in the mortality of metastatic CRC (mCRC). The causes of 5-FU resistance are multi-factorial, and besides DNA mismatch repair deficiency (MMR-D), there are no widely accepted criteria for determining which CRC patients are not likely to be responsive to 5-FU-based therapy. Thus, there is a need to systematically understand the mechanistic basis for 5-FU treatment failure and an urgent need to develop new approaches for circumventing the major causes of 5-FU resistance. In this manuscript, we review mechanisms of 5-FU resistance with an emphasis on: (1) altered anabolic metabolism limiting the formation of the primary active metabolite Fluorodeoxyuridylate (5-Fluoro-2'-deoxyuridine-5'-O-monophosphate; FdUMP); (2) elevated expression or activity of the primary enzymatic target thymidylate synthase (TS); and (3) dysregulated programmed cell death as important causes of 5-FU resistance. Importantly, these causes of 5-FU resistance can potentially be overcome through the use of next-generation fluoropyrimidine (FP) polymers (e.g., CF10) that display reduced dependence on anabolic metabolism and more potent TS inhibitory activity.
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Affiliation(s)
- William H. Gmeiner
- Department of Cancer Biology and Comprehensive Cancer Center, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA
- Integrative Physiology and Pharmacology Graduate Program, Institution, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA
| | - Charles Chidi Okechukwu
- Department of Cancer Biology and Comprehensive Cancer Center, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA
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3
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Biochemical analysis based on optical detection integrated microfluidic chip. Trends Analyt Chem 2023. [DOI: 10.1016/j.trac.2022.116865] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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4
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Kagawa Y, Sone K, Oguri T, Horiuchi M, Fukuda S, Uemura T, Takakuwa O, Maeno K, Fukumitsu K, Kanemitsu Y, Tajiri T, Ohkubo H, Takemura M, Ito Y, Niimi A. Predictive role of CYFRA 21-1 for S-1 monotherapy in non-small cell lung cancer patients. Respir Investig 2022; 60:393-399. [PMID: 35216954 DOI: 10.1016/j.resinv.2021.11.014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 11/05/2021] [Accepted: 11/23/2021] [Indexed: 06/14/2023]
Abstract
BACKGROUND S-1, an oral fluoropyrimidine derivative, is widely used for the treatment of several solid tumors. However, there are no predictive markers for its effectiveness. METHODS We retrospectively screened 108 patients with advanced non-small cell lung cancer (NSCLC) treated via S-1 monotherapy and investigated its relationship with cytokeratin 19 fragment (CYFRA 21-1) and CEA pretreatment levels. RESULTS Sixty-one patients with high CYFRA 21-1 levels had a statistically significant shorter progression-free survival (PFS) and overall survival (OS) than 46 patients with normal levels (median PFS = 42 days vs. 70 days, respectively; p = 0.0014; median OS = 197 days vs. 316 days, respectively, p = 0.0239). CONCLUSIONS Serum CYFRA 21-1 levels have predictive and prognostic roles in the management of patients with advanced NSCLC on S-1 monotherapy.
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Affiliation(s)
- Yusuke Kagawa
- Department of Respiratory Medicine, Allergy and Clinical Immunology, Nagoya, Japan
| | - Kazuki Sone
- Department of Respiratory Medicine, Allergy and Clinical Immunology, Nagoya, Japan
| | - Tetsuya Oguri
- Department of Respiratory Medicine, Allergy and Clinical Immunology, Nagoya, Japan; Department of Education and Research Center for Community Medicine, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan.
| | - Minoru Horiuchi
- Department of Respiratory Medicine, Allergy and Clinical Immunology, Nagoya, Japan
| | - Satoshi Fukuda
- Department of Respiratory Medicine, Allergy and Clinical Immunology, Nagoya, Japan
| | - Takehiro Uemura
- Department of Respiratory Medicine, Allergy and Clinical Immunology, Nagoya, Japan
| | - Osamu Takakuwa
- Department of Respiratory Medicine, Allergy and Clinical Immunology, Nagoya, Japan
| | - Ken Maeno
- Department of Respiratory Medicine, Allergy and Clinical Immunology, Nagoya, Japan
| | - Kennsuke Fukumitsu
- Department of Respiratory Medicine, Allergy and Clinical Immunology, Nagoya, Japan
| | - Yoshihiro Kanemitsu
- Department of Respiratory Medicine, Allergy and Clinical Immunology, Nagoya, Japan
| | - Tomoko Tajiri
- Department of Respiratory Medicine, Allergy and Clinical Immunology, Nagoya, Japan
| | - Hirotsugu Ohkubo
- Department of Respiratory Medicine, Allergy and Clinical Immunology, Nagoya, Japan
| | - Masaya Takemura
- Department of Respiratory Medicine, Allergy and Clinical Immunology, Nagoya, Japan; Department of Education and Research Center for Community Medicine, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Yutaka Ito
- Department of Respiratory Medicine, Allergy and Clinical Immunology, Nagoya, Japan
| | - Akio Niimi
- Department of Respiratory Medicine, Allergy and Clinical Immunology, Nagoya, Japan
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5
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Mao C, Zeng X, Zhang C, Yang Y, Xiao X, Luan S, Zhang Y, Yuan Y. Mechanisms of Pharmaceutical Therapy and Drug Resistance in Esophageal Cancer. Front Cell Dev Biol 2021; 9:612451. [PMID: 33644048 PMCID: PMC7905099 DOI: 10.3389/fcell.2021.612451] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Accepted: 01/04/2021] [Indexed: 02/05/2023] Open
Abstract
Pharmaceutical therapies are essential for esophageal cancer (EC). For the advanced EC, the neoadjuvant therapy regimen, including chemotherapy plus radiotherapy and/or immunotherapy, is effective to achieve clinical benefit, even pathological complete response. For the unresectable, recurrent, and metastatic EC, the pharmaceutical therapy is the limited effective regimen to alleviate the disease and prolong the progression-free survival and overall survival. In this review, we focus on the pharmaceutical applications in EC treatment including cytotoxic agents, molecular targeted antibodies, and immune checkpoint inhibitors (ICIs). The chemotherapy regimen is based on cytotoxic agents such as platinum-based complexes, fluorinated pyrimidines and taxenes. Although the cytotoxic agents have been developed in past decades, the standard chemotherapy regimen is still the cisplatin and 5-FU or paclitaxel because the derived drugs have no significant advantages of overcoming the shortcomings of side effects and drug resistance. The targeted molecular therapy is an essential supplement for chemotherapy; however, there are only a few targeted therapies available in clinical practice. Trastuzumab and ramucirumab are the only two molecular therapy drugs which are approved by the US Food and Drug Administration to treat advanced and/or metastatic EC. Although the targeted therapy usually achieves effective benefits in the early stage therapy of EC, the patients will always develop drug resistance during treatment. ICIs have had a significant impact on routine clinical practice in cancer treatment. The anti-programmed cell death-1 monoclonal antibodies pembrolizumab and nivolumab, as the ICIs, are recommended for advanced EC by several clinical trials. However, the significant issues of pharmaceutical treatment are still the dose-limiting side effects and primary or secondary drug resistance. These defects of pharmaceutical therapy restrain the clinical application and diminish the effectiveness of treatment.
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Affiliation(s)
- Chengyi Mao
- Department of Thoracic Surgery West China Hospital, Sichuan University, Chengdu, China
| | - Xiaoxi Zeng
- West China Biomedical Big Data Center, West China Hospital, Sichuan University, Chengdu, China
| | - Chao Zhang
- West China Biomedical Big Data Center, West China Hospital, Sichuan University, Chengdu, China
| | - Yushang Yang
- Department of Thoracic Surgery West China Hospital, Sichuan University, Chengdu, China
| | - Xin Xiao
- Department of Thoracic Surgery West China Hospital, Sichuan University, Chengdu, China
| | - Siyuan Luan
- Department of Thoracic Surgery West China Hospital, Sichuan University, Chengdu, China
| | - Yonggang Zhang
- Department of Periodical Press, National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, China
- Nursing Key Laboratory of Sichuan Province, Chengdu, China
- Chinese Evidence-Based Medicine Center, West China Hospital, Sichuan University, Chengdu, China
| | - Yong Yuan
- Department of Thoracic Surgery West China Hospital, Sichuan University, Chengdu, China
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6
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Chemistry of Fluorinated Pyrimidines in the Era of Personalized Medicine. Molecules 2020; 25:molecules25153438. [PMID: 32751071 PMCID: PMC7435603 DOI: 10.3390/molecules25153438] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 07/23/2020] [Accepted: 07/28/2020] [Indexed: 12/13/2022] Open
Abstract
We review developments in fluorine chemistry contributing to the more precise use of fluorinated pyrimidines (FPs) to treat cancer. 5-Fluorouracil (5-FU) is the most widely used FP and is used to treat > 2 million cancer patients each year. We review methods for 5-FU synthesis, including the incorporation of radioactive and stable isotopes to study 5-FU metabolism and biodistribution. We also review methods for preparing RNA and DNA substituted with FPs for biophysical and mechanistic studies. New insights into how FPs perturb nucleic acid structure and dynamics has resulted from both computational and experimental studies, and we summarize recent results. Beyond the well-established role for inhibiting thymidylate synthase (TS) by the 5-FU metabolite 5-fluoro-2′-deoxyuridine-5′-O-monophosphate (FdUMP), recent studies have implicated new roles for RNA modifying enzymes that are inhibited by 5-FU substitution including tRNA methyltransferase 2 homolog A (TRMT2A) and pseudouridylate synthase in 5-FU cytotoxicity. Furthermore, enzymes not previously implicated in FP activity, including DNA topoisomerase 1 (Top1), were established as mediating FP anti-tumor activity. We review recent literature summarizing the mechanisms by which 5-FU inhibits RNA- and DNA-modifying enzymes and describe the use of polymeric FPs that may enable the more precise use of FPs for cancer treatment in the era of personalized medicine.
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7
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Fluoropyrimidine Modulation of the Anti-Tumor Immune Response-Prospects for Improved Colorectal Cancer Treatment. Cancers (Basel) 2020; 12:cancers12061641. [PMID: 32575843 PMCID: PMC7352193 DOI: 10.3390/cancers12061641] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Revised: 06/18/2020] [Accepted: 06/19/2020] [Indexed: 02/07/2023] Open
Abstract
Chemotherapy modulates the anti-tumor immune response and outcomes depend on the balance of favorable and unfavorable effects of drugs on anti-tumor immunity. 5-Florouracil (5-FU) is widely used in adjuvant chemotherapy regimens to treat colorectal cancer (CRC) and provides a survival benefit. However, survival remains poor for CRC patients with advanced and metastatic disease and immune checkpoint blockade therapy benefits only a sub-set of CRC patients. Here we discuss the effects of 5-FU-based chemotherapy regimens to the anti-tumor immune response. We consider how different aspects of 5-FU's multi-factorial mechanism differentially affect malignant and immune cell populations. We summarize recent studies with polymeric fluoropyrimidines (e.g., F10, CF10) that enhance DNA-directed effects and discuss how such approaches may be used to enhance the anti-tumor immune response and improve outcomes.
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8
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Feasibility of Known RNA Polymerase Inhibitors as Anti-SARS-CoV-2 Drugs. Pathogens 2020; 9:pathogens9050320. [PMID: 32357471 PMCID: PMC7281371 DOI: 10.3390/pathogens9050320] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Revised: 04/23/2020] [Accepted: 04/24/2020] [Indexed: 12/22/2022] Open
Abstract
Coronaviruses (CoVs) are positive-stranded RNA viruses that infect humans and animals. Infection by CoVs such as HCoV-229E, -NL63, -OC43 and -HKU1 leads to the common cold, short lasting rhinitis, cough, sore throat and fever. However, CoVs such as Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV), Middle East Respiratory Syndrome Coronavirus (MERS-CoV), and the newest SARS-CoV-2 (the causative agent of COVID-19) lead to severe and deadly diseases with mortality rates ranging between ~1 to 35% depending on factors such as age and pre-existing conditions. Despite continuous global health threats to humans, there are no approved vaccines or drugs targeting human CoVs, and the recent outbreak of COVID-19 emphasizes an urgent need for therapeutic interventions. Using computational and bioinformatics tools, here we present the feasibility of reported broad-spectrum RNA polymerase inhibitors as anti- SARS-CoV-2 drugs targeting its main RNA polymerase, suggesting that investigational and approved nucleoside RNA polymerase inhibitors have potential as anti-SARS-CoV-2 drugs. However, we note that it is also possible for SARS-CoV-2 to evolve and acquire drug resistance mutations against these nucleoside inhibitors.
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9
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Knikman JE, Rosing H, Guchelaar H, Cats A, Beijnen JH. A review of the bioanalytical methods for the quantitative determination of capecitabine and its metabolites in biological matrices. Biomed Chromatogr 2020; 34:e4732. [DOI: 10.1002/bmc.4732] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Revised: 10/21/2019] [Accepted: 10/22/2019] [Indexed: 12/19/2022]
Affiliation(s)
- Jonathan E. Knikman
- Division of PharmacologyThe Netherlands Cancer Institute Amsterdam The Netherlands
| | - Hilde Rosing
- Department of Pharmacy & PharmacologyThe Netherlands Cancer Institute Amsterdam The Netherlands
| | - Henk‐Jan Guchelaar
- Department of Clinical Pharmacy and ToxicologyLeiden University Medical Center Leiden The Netherlands
| | - A. Cats
- Department of Gastroenterology and Hepatology, Division of Medical OncologyThe Netherlands Cancer Institute Amsterdam The Netherlands
| | - Jos H. Beijnen
- Division of PharmacologyThe Netherlands Cancer Institute Amsterdam The Netherlands
- Department of Pharmacy & PharmacologyThe Netherlands Cancer Institute Amsterdam The Netherlands
- Division of Pharmacoepidemiology and Clinical Pharmacology, Utrecht Institute for Pharmaceutical SciencesUtrecht University Utrecht The Netherlands
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10
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Altaf AA, Khan N, Lal B, Badshah A. Synthesis, characterization and DNA-intercalation studies of two ferrocene-based Fe-Sn heterobimetallic compounds, and crystal structure of trimethyltin (p-ferrocenyl)benzoate. J COORD CHEM 2017. [DOI: 10.1080/00958972.2017.1384547] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- Ataf Ali Altaf
- Department of Chemistry, University of Gujrat, Gujrat, Pakistan
| | - Nasir Khan
- Department of Chemistry, Quaid-i-Azam University, Islamabad, Pakistan
| | - Bhajan Lal
- Department of Energy System Engineering, Sukkur Institute of Business Administration, Sukkur, Pakistan
| | - Amin Badshah
- Department of Chemistry, Quaid-i-Azam University, Islamabad, Pakistan
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11
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Derissen EJB, Hillebrand MJX, Rosing H, Schellens JHM, Beijnen JH. Development of an LC-MS/MS assay for the quantitative determination of the intracellular 5-fluorouracil nucleotides responsible for the anticancer effect of 5-fluorouracil. J Pharm Biomed Anal 2015; 110:58-66. [PMID: 25804433 DOI: 10.1016/j.jpba.2015.02.051] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2014] [Revised: 01/26/2015] [Accepted: 02/28/2015] [Indexed: 11/19/2022]
Abstract
5-Fluorouracil (5-FU) and its oral prodrug capecitabine are among the most widely used chemotherapeutics. For cytotoxic activity, 5-FU requires cellular uptake and intracellular metabolic activation. Three intracellular formed metabolites are responsible for the antineoplastic effect of 5-FU: 5-fluorouridine 5'-triphosphate (FUTP), 5-fluoro-2'-deoxyuridine 5'-triphosphate (FdUTP) and 5-fluoro-2'-deoxyuridine 5'-monophosphate (FdUMP). In this paper, we describe the development of an LC-MS/MS assay for quantification of these active 5-FU nucleotides in peripheral blood mononuclear cells (PBMCs). Because the intracellular 5-FU nucleotide concentrations were very low, maximization of the release from the cell matrix and minimization of interference were critical factors. Therefore, a series of experiments was performed to select the best method for cell lysis and nucleotide extraction. Chromatography was optimized to obtain separation from endogenous nucleotides, and the effect of different cell numbers was examined. The assay was validated for the following concentration ranges in PBMC lysate: 0.488-19.9 nM for FUTP, 1.66-67.7 nM for FdUTP and 0.748-30.7 nM for FdUMP. Accuracies were between -2.2 and 7.0% deviation for all analytes, and the coefficient of variation values were ≤ 4.9%. The assay was successfully applied to quantify 5-FU nucleotides in PBMC samples from patients treated with capecitabine and patients receiving 5-FU intravenously. FUTP amounts up to 3054 fmol/10(6) PBMCs and FdUMP levels up to 169 fmol/10(6) PBMCs were measured. The FdUTP concentrations were below the lower limit of quantification. To our knowledge, this is the first time that 5-FU nucleotides were quantified in cells from patients treated with 5-FU or capecitabine without using a radiolabel.
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Affiliation(s)
- Ellen J B Derissen
- Department of Pharmacy & Pharmacology, Antoni van Leeuwenhoek Hospital - The Netherlands Cancer Institute, Louwesweg 6, 1066 EC Amsterdam, The Netherlands.
| | - Michel J X Hillebrand
- Department of Pharmacy & Pharmacology, Antoni van Leeuwenhoek Hospital - The Netherlands Cancer Institute, Louwesweg 6, 1066 EC Amsterdam, The Netherlands
| | - Hilde Rosing
- Department of Pharmacy & Pharmacology, Antoni van Leeuwenhoek Hospital - The Netherlands Cancer Institute, Louwesweg 6, 1066 EC Amsterdam, The Netherlands
| | - Jan H M Schellens
- Department of Clinical Pharmacology, The Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands; Science Faculty, Utrecht Institute for Pharmaceutical Sciences (UIPS), Division of Pharmaco-epidemiology & Clinical Pharmacology, Utrecht University, P.O. Box 80082, 3508 TB Utrecht, The Netherlands
| | - Jos H Beijnen
- Department of Pharmacy & Pharmacology, Antoni van Leeuwenhoek Hospital - The Netherlands Cancer Institute, Louwesweg 6, 1066 EC Amsterdam, The Netherlands; Science Faculty, Utrecht Institute for Pharmaceutical Sciences (UIPS), Division of Pharmaco-epidemiology & Clinical Pharmacology, Utrecht University, P.O. Box 80082, 3508 TB Utrecht, The Netherlands
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12
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Dhakshinamoorthy A, Garcia H. Metal–organic frameworks as solid catalysts for the synthesis of nitrogen-containing heterocycles. Chem Soc Rev 2014; 43:5750-65. [DOI: 10.1039/c3cs60442j] [Citation(s) in RCA: 391] [Impact Index Per Article: 39.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
This Critical Review summarizes the recent developments in the use of metal–organic frameworks as catalysts for the synthesis of nitrogen-containing heterocycles.
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Affiliation(s)
| | - Hermenegildo Garcia
- Instituto Universitario de Tecnología Química CSIC-UPV
- Univ. Politec. De Valencia
- 46022 Valencia, Spain
- Center of Excellence for Advanced Materials Research
- King Abdulaziz University
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13
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Jansen RS, Rosing H, Schellens JHM, Beijnen JH. Deoxyuridine analog nucleotides in deoxycytidine analog treatment: secondary active metabolites? Fundam Clin Pharmacol 2011; 25:172-85. [PMID: 20199587 DOI: 10.1111/j.1472-8206.2010.00823.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Deoxycytidine analogs (dCa's) are nucleosides widely used in anticancer and anti (retro) viral therapies. Intracellularly phosphorylated dCa anabolites are considered to be their main active metabolites. This article reviews the literature on the formation and pharmacological activity of deaminated dCa nucleotides. Most dCa's are rapidly deaminated into deoxyuridine analogs (dUa's) which are only slowly phosphorylated and therefore relatively inactive. dUa nucleotides are, however, also formed via deamination of dCa monophosphates by deoxycytidine monophosphate deaminase (dCMPD). dUa-monophosphates can interact with thymidylate synthase (TS), whereas dUa-triphosphates are incorporated into nucleic acids and interfere with polymerases. Administration of dCa's as monophosphate prodrugs or co-administration of the cytidine deaminase inhibitor tetrahydrouridine (THU) does not prevent dUa nucleotide formation which is, on the other hand, influenced by the dose and dCMPD activity. Taken together, these observations show that the formation of dUa nucleotides is a common phenomenon in treatment with dCa's and these compounds may play a role in treatment outcome. We conclude that more attention should be given to these relatively unknown, but potentially important metabolites.
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Affiliation(s)
- Robert S Jansen
- Department of Pharmacy & Pharmacology, Slotervaart Hospital/The Netherlands Cancer Institute, Louwesweg 6, 1066 EC Amsterdam, The Netherlands.
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14
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Tsume Y, Provoda CJ, Amidon GL. The achievement of mass balance by simultaneous quantification of floxuridine prodrug, floxuridine, 5-fluorouracil, 5-dihydrouracil, α-fluoro-β-ureidopropionate, α-fluoro-β-alanine using LC-MS. J Chromatogr B Analyt Technol Biomed Life Sci 2011; 879:915-20. [PMID: 21450537 DOI: 10.1016/j.jchromb.2011.02.045] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2010] [Revised: 02/22/2011] [Accepted: 02/27/2011] [Indexed: 12/21/2022]
Abstract
5-Fluoro-2'-deoxyuridine (floxuridine, 5-FdUrd) and 5-fluorouracil (5-FU) are widely used for the treatment of colorectal cancers. The mechanisms of action of 5-FdUrd and 5-FU, as well as the biochemical pathway responsible for their metabolism, are well understood. Identification of every metabolite and achieving mass balance by conventional UV absorption-based HPLC analysis are not feasible because the metabolites beyond 5-FU in the 5-FdUrd metabolic pathway are undetectable by UV light. We therefore established a mass spectrometry method, designed for fast and convenient analysis, for simultaneously measuring 5-FdUrd, 5-FU, and their metabolites. Linearity, precision and accuracy were validated in the concentration ranges studied for each compound. Hydrolysis studies of 5-FdUrd and amino acid mono ester prodrugs of 5-FdUrd in Capan-2 cell homogenates were carried out and the achievement of mass balance was established with this method (recovery of 5'-O-l-leucyl-FdUrd was 96.6-108.2% and that of 5-FdUrd was 79.4-117.4%). This simple LC-MS method achieves reliable quantitation and mass balance of 5-FdUrd, 5-FU, and their metabolites and can be effectively utilized for further kinetic studies.
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Affiliation(s)
- Yasuhiro Tsume
- Department of Pharmaceutical Science, College of Pharmacy, University of Michigan, Ann Arbor, MI 48109-1065, USA
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15
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Réti A, Barna G, Pap E, Adleff V, L Komlósi V, Jeney A, Kralovánszky J, Budai B. Enhancement of 5-fluorouracil efficacy on high COX-2 expressing HCA-7 cells by low dose indomethacin and NS-398 but not on low COX-2 expressing HT-29 cells. Pathol Oncol Res 2010; 15:335-44. [PMID: 19048402 DOI: 10.1007/s12253-008-9126-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/01/2008] [Accepted: 11/05/2008] [Indexed: 01/31/2023]
Abstract
The antiproliferative effect of 5-fluorouracil (5-FU) in the presence of low dose non-steroidal anti-inflammatory drugs (NSAIDs) on high cyclooxygenase-2 (COX-2)-expressing HCA-7 and low COX-2-expressing HT-29 colon carcinoma cell lines was investigated. Pharmacogenetic parameters were studied to characterize the 5-FU sensitivity of the two cell lines. Thymidylate synthase (TS) and methylenetetrahydrofolate reductase (MTHFR) polymorphisms were determined by PCR analysis. Cell proliferation was measured by SRB assay, cell cycle distribution and apoptosis by FACS analysis. Cyclooxygenase expression was detected by Western blot and also by fluorescence microscopy. Prostaglandin E(2) (PGE(2)) levels were investigated with ELISA kit. The HT-29 cell line was found to be homozygous for TS 2R and 1494ins6 and T homozygous for MTHFR 677 polymorphisms predicting high 5-FU sensitivity (IC(50): 10 microM). TS 3R homozygosity, TS 1496del6 and MTHFR 677CT heterozygosity may explain the modest 5-FU sensitivity (IC(50): 1.1 mM) of the HCA-7 cell line. Indomethacin and NS-398 (10 microM and 1.77 microM, respectively) reduced the PGE(2) level in HCA-7 cells (>90%). Low concentrations of NSAIDs without antiproliferative potency increased the S-phase arrest and enhanced the cytotoxic action of 5-FU only in HCA-7 cells after 48-hours treatment. The presented data suggested that the enhancement of 5-FU cytotoxicity by indomethacin or NS-398 applied in low dose is related to the potency of NSAIDs to modulate the cell-cycle distribution and the apoptosis; however, it seems that this effect might be dependent on cell phenotype, namely on the COX-2 expression.
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Affiliation(s)
- Andrea Réti
- National Institute of Oncology, Budapest, Hungary
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Kalra AV, Campbell RB. Mucin overexpression limits the effectiveness of 5-FU by reducing intracellular drug uptake and antineoplastic drug effects in pancreatic tumours. Eur J Cancer 2008; 45:164-73. [PMID: 19046630 DOI: 10.1016/j.ejca.2008.10.008] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2008] [Revised: 08/20/2008] [Accepted: 10/07/2008] [Indexed: 02/01/2023]
Abstract
Current treatments for pancreatic cancer have failed to effectively manage the disease, and hence, more effective treatment approaches are urgently needed. Studies suggest that mucin O-glycosylation limits the cytotoxic effect of fluorouracil (5-FU) against the growth of human pancreatic cancer cells in vitro. In the present study, we investigated the relationship between the levels of mucin O-glycosylation expressed in pancreatic tumours and the antitumour effect of 5-FU. The inhibition of O-glycosylation was achieved by intratumoural (IT) injections of benzyl-alpha-GalNAc. Immunohistochemical staining of human pancreatic tumours revealed relatively high (Capan-1) and moderate (HPAF-II) expression levels of MUC1 mucin compared to MUC1 negative control (U-87 MG human glioblastoma) tumours. The antitumour effects of 5-FU (given systemically) against Capan-1 tumours improved significantly following IT injections of benzyl-alpha-GalNAc. Histochemical staining of tumour sections revealed a reduced number of neoplastic cells in tumours exposed to benzyl-alpha-GalNAc prior to 5-FU treatment compared to 5-FU alone. Furthermore, intracellular uptake of 5-FU by Capan-1 cells was significantly greater following injections of benzyl-alpha-GalNAc; however, no such effect was observed with U-87 MG cells. Mucin overexpression reduces intracellular drug uptake, antineoplastic and antitumour drug effects, which may have important clinical implications in treatment.
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Affiliation(s)
- Ashish V Kalra
- Northeastern University, Bouvé College of Health Sciences, Department of Pharmaceutical Sciences, Boston, MA 02115, USA
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17
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Seela F, Xu K. DNA with stable fluorinated dA and dG substitutes: syntheses, base pairing and 19F-NMR spectra of 7-fluoro-7-deaza-2'-deoxyadenosine and 7-fluoro-7-deaza-2'-deoxyguanosine. Org Biomol Chem 2008; 6:3552-60. [PMID: 19082156 DOI: 10.1039/b806145a] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Fluorinated DNA containing stable fluorine substituents in the "purine" base were synthesized for the first time. For this, the phosphoramidites of 7-fluoro-7-deaza-2'-deoxyadenosine and 7-fluoro-7-deaza-2'-deoxyguanosine were prepared and oligonucleotides were synthesized. The 7-fluoro substitution leads to increased duplex stability and more selective base pairing compared to the non-functionalized 7-deazapurine oligonucleotides. (19)F NMR spectra of fluorinated nucleosides, single stranded oligonucleotides and DNA duplex show only a single signal for one fluorine modification. The NMR sensitive (19)F spin or the positron emitting (18)F isotope make these compounds applicable for DNA detection or imaging in vitro and in vivo.
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Affiliation(s)
- Frank Seela
- Laboratory of Bioorganic Chemistry and Chemical Biology, Center for Nanotechnology, Heisenbergstrasse 11, 48149 Münster, Germany.
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18
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Kalra AV, Campbell RB. Mucin impedes cytotoxic effect of 5-FU against growth of human pancreatic cancer cells: overcoming cellular barriers for therapeutic gain. Br J Cancer 2007; 97:910-8. [PMID: 17912239 PMCID: PMC2360416 DOI: 10.1038/sj.bjc.6603972] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Mucins are high molecular weight glycoproteins expressed on the apical surface of normal epithelial cells. In cancer disease mucins are overexpressed on the entire cellular surface. Overexpression of MUC1 mucin in pancreatic tumours has been correlated with poor patient survival. Current chemotherapeutic approaches such as 5-fluorouracil (5-FU) has produced limited clinical success. In this study we investigated the role of mucin in cytotoxic drug treatment to determine whether the extracellular domain of mucin impedes cytotoxic drug action of 5-FU. Human pancreatic cancer cells revealed high and relatively moderate MUC1 levels for Capan-1 and HPAF-II, respectively, compared to MUC1 negative control (U-87 MG glioblastoma) that showed relatively non-specific anti-MUC1 uptake. Benzyl-alpha-GalNAc (O-glycosylation inhibitor) was used to reduce mucin on cell surfaces, and neuraminidase was used to hydrolyse sialic acid at the distal end of carbohydrate chains. Benzyl-alpha-GalNAc had no effect on cell morphology or proliferation at the concentrations employed. The inhibition of O-glycosylation resulted in significant 5-FU antiproliferative activity against Capan-1 and HPAF-II, but not against U-87 MG. However, the exposure of cells to neuraminidase failed to improve the cytotoxic action of 5-FU. Our experimental findings suggest that the overexpression of mucin produced by human pancreatic tumours might limit the effectiveness of chemotherapy.
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Affiliation(s)
- A V Kalra
- Department of Pharmaceutical Sciences, Northeastern University, 360 Huntington Avenue, Bouvé College of Health Sciences, Boston, MA 02115, USA
| | - R B Campbell
- Department of Pharmaceutical Sciences, Northeastern University, 360 Huntington Avenue, Bouvé College of Health Sciences, Boston, MA 02115, USA
- E-mail:
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19
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Kalra AV, Campbell RB. Development of 5-FU and Doxorubicin-Loaded Cationic Liposomes against Human Pancreatic Cancer: Implications for Tumor Vascular Targeting. Pharm Res 2006; 23:2809-17. [PMID: 17066329 DOI: 10.1007/s11095-006-9113-3] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2006] [Accepted: 07/06/2006] [Indexed: 10/24/2022]
Abstract
PURPOSE Human pancreatic adenocarcinoma is a major leading cause of cancer mortality in the United States. Given that current strategies are relatively ineffective against this disease, new treatments are being developed. Liposomes possessing relatively high cationic lipid content preferentially accumulate in tumor angiogenic vessels compared to vessels in normal tissues. We therefore seek to develop cationic liposomes for targeting pancreatic tumor vessels. MATERIALS AND METHODS We report development of 5-fluorouracil (5-FU) and doxorubicin hydrochloride (DOX) loaded in PEGylated cationic liposomes (PCLs). We evaluate cell association, intracellular fate, and cytotoxicity. Human pancreatic cancer cells HPAF-II and Capan-1, and endothelial cells HMEC-1 and HUVEC were used in this study. Intratumoral distribution of PCLs in (HPAF-II) tumors was determined by intravital microscopy. RESULTS HUVEC and HMEC-1 were most susceptible to 5-FU after 24 and 48 h, compared to HPAF-II and Capan-1. We observed >90% incorporation of 5-FU and DOX in PCLs for 3-20 mol% preparations, with reduced incorporation for >20 mol% formulations. PCLs showed significantly higher association with human endothelial versus pancreatic cancer cells, and improved growth inhibitory properties of DOX. Intravital microscopy revealed distribution of PCLs along HPAF-II vessels. CONCLUSIONS Targeting human pancreatic cancer with PCLs may represent a rational alternative to conventional strategies.
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Affiliation(s)
- Ashish V Kalra
- Department of Pharmaceutical Sciences, Bouvé College of Health Sciences, Northeastern University, 360 Huntington Avenue, 110 Mugar Hall, Boston, Massachusetts 02115, USA
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20
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Affiliation(s)
- Mark Lukin
- Department of Pharmacological Sciences, State University of New York at Stony Brook, School of Medicine, 11794-8651, USA
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21
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Malet-Martino M, Gilard V, Desmoulin F, Martino R. Fluorine nuclear magnetic resonance spectroscopy of human biofluids in the field of metabolic studies of anticancer and antifungal fluoropyrimidine drugs. Clin Chim Acta 2006; 366:61-73. [PMID: 16337167 DOI: 10.1016/j.cca.2005.10.013] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2005] [Revised: 10/13/2005] [Accepted: 10/14/2005] [Indexed: 11/20/2022]
Abstract
Fluorine-19 nuclear magnetic resonance (19F NMR) spectroscopy provides a highly specific tool for the detection, identification and quantification of fluorine-containing drugs and their metabolites in biofluids. The value and difficulties encountered in investigations on drug metabolism are first discussed. Then the metabolism of three fluoropyrimidines in clinical use, 5-fluorouracil, 5-fluorocytosine and capecitabine are reported. Besides the parent drug and the already known fluorinated metabolites, 12 new metabolites were identified for the first time with 19F NMR in human biofluids. Nine of them can only be observed with this technique: fluoride ion, N-carboxy-alpha-fluoro-beta-alanine, alpha-fluoro-beta-alanine conjugate with deoxycholic acid, 2-fluoro-3-hydroxypropanoic acid, fluoroacetic acid, O2-beta-glucuronide of fluorocytosine, fluoroacetaldehyde hydrate and its adduct with urea, fluoromalonic acid semi-aldehyde adducts with urea. This emphasizes the high analytical potential of 19F NMR for the furtherance in the understanding of fluoropyrimidine catabolic pathways. 19F NMR should also play a role in the therapeutic monitoring of FU and its prodrugs in specific groups of patients, e.g. hemodialyzed patients or patients with deficiency in FU catabolic enzymes.
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Affiliation(s)
- Myriam Malet-Martino
- Groupe de RMN Biomédicale, Laboratoire SPCMIB (UMR CNRS 5068), Université Paul Sabatier, Toulouse, France
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22
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Martino R, Gilard V, Desmoulin F, Malet-Martino M. Fluorine-19 or phosphorus-31 NMR spectroscopy: A suitable analytical technique for quantitative in vitro metabolic studies of fluorinated or phosphorylated drugs. J Pharm Biomed Anal 2005; 38:871-91. [PMID: 16087049 DOI: 10.1016/j.jpba.2005.01.047] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2004] [Revised: 12/22/2004] [Accepted: 01/25/2005] [Indexed: 01/23/2023]
Abstract
Fluorine-19 or phosphorus-31 NMR (19F NMR or 31P NMR) spectroscopy provides a highly specific tool for identification of fluorine- or phosphorus-containing drugs and their metabolites in biological media as well as a suitable analytical technique for their absolute quantification. This article focuses on the application of in vitro 19F or 31P NMR to the quantitative metabolic studies of some fluoropyrimidine or oxazaphosphorine drugs in clinical use. The first part presents an overview of the advantages (non-destructive and non-selective direct quantitative study of the biological matrices) and limitations (expensive cost of the spectrometers, limited mass or concentration sensitivity) of NMR spectroscopy. The second part deals with the criteria to be considered for successful quantification by NMR (uniform excitation over the entire spectral width of the spectrum, resonance signals properly characterised by taking into account T1 values and avoiding NOE enhancements, optimisation of the data processing, choice of a suitable standard reference). The third and fourth parts report some examples of quantification of 5-fluorouracil, its prodrug capecitabine, 5-fluorocytosine and their metabolites in bulk solutions (biofluids, tissue extracts, perfusates and culture media) and heterogeneous media (excised tissues and packed intact cells) as well as cyclophosphamide and ifosfamide in biofluids. These two parts emphasise the high potential of in vitro 19F or 31P NMR for absolute quantification, in a single run, of all the fluorine- or phosphorus-containing species in the matrices analysed. The limit of quantification in bulk solutions is 1-3 microM for 19F NMR and approximately 10 microM for 31P NMR. In heterogeneous media analysed with 19F NMR, it is 2-5 nmol in excised tissues and cell pellets.
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Affiliation(s)
- Robert Martino
- Groupe de RMN Biomédicale, Laboratoire SPCMIB (UMR CNRS 5068), Université Paul Sabatier, 118 route de Narbonne, 31062 Toulouse Cedex, France
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23
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Expression and localization of human multidrug resistance protein (ABCC) family members in pancreatic carcinoma. Int J Cancer 2005; 115:359-67. [PMID: 15688370 DOI: 10.1002/ijc.20831] [Citation(s) in RCA: 136] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Pancreatic ductal adenocarcinoma is among the top 10 causes of death from cancer in industrialized countries. In comparison with other gastrointestinal malignancies, pancreatic cancer is one of the tumors most resistant to chemotherapy. An important mechanism of tumor multidrug resistance is increased drug efflux mediated by several transporters of the ABC superfamily. Especially BCRP (ABCG2), MDR1 P-glycoprotein (ABCB1) and members of the MRP (ABCC) family are important in mediating drug resistance. The MRP family consists of 9 members (MRP1-MRP9) with MRP1-MRP6 being best characterized with respect to protein localization and substrate selectivity. Here, we quantified the mRNA expression of BCRP and of all MRP family members in normal human pancreas and pancreatic carcinoma and analyzed the mRNA level of the transporters most abundantly expressed in pancreatic tissue, BCRP, MRP1, MRP3, MRP4 and MRP5, in 37 tissue samples. In addition, we determined the localization of the 4 MRP proteins in normal human pancreas and in pancreatic carcinoma. The expression of BCRP, MRP1 and MRP4 mRNA did not correlate with tumor stage or grading. On the other hand, the expression of MRP3 mRNA was upregulated in pancreatic carcinoma samples and was correlated with tumor grading. The MRP5 mRNA level was significantly higher in pancreatic carcinoma tissue compared to normal pancreatic tissue. These data suggest that MRP3 and MRP5 are involved in drug resistance of pancreatic tumors and that quantitative analysis of their expression may contribute to predict the benefit of chemotherapy in patients with pancreatic cancer.
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24
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Fischer PM, Gianella-Borradori A. Recent progress in the discovery and development of cyclin-dependent kinase inhibitors. Expert Opin Investig Drugs 2005; 14:457-77. [PMID: 15882121 DOI: 10.1517/13543784.14.4.457] [Citation(s) in RCA: 101] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Cyclin-dependent kinases (CDKs) have long been known to be the main facilitators of the cell proliferation cycle. However, they also play important roles in the regulation of the RNA polymerase II transcription cycle. Cancer cells display aberrant cell cycle regulation to gain proliferative advantages and they also appear to have an exaggerated dependence on RNA polymerase II transcriptional activity to sustain pro-survival and antiapoptotic signalling. A picture is now starting to emerge that both the cell-cycle and transcriptional functions of CDKs can be exploited pharmacologically with CDK inhibitors that possess appropriate selectivity profiles. In this article, recent advances into these mechanistic insights and how they can guide clinical development in terms of choice of indication are reviewed, as well as combinations with existing chemotherapies. An overview is also given of recent clinical trial results with the lead CDK inhibitor drug candidates seliciclib (CYC202, (R)-roscovitine; Cyclacel) and alvocidib (flavopiridol; Aventis-NCI), as well as the development of other clinical entries and advanced preclinical compounds. The discussion focuses on oncology, but we point out recent results with CDK inhibitors in virology and nephrology.
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Affiliation(s)
- Peter M Fischer
- Cyclacel Limited, James Lindsay Place, Dundee DD1 5JJ, Scotland, UK.
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25
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Meyers M, Wagner MW, Mazurek A, Schmutte C, Fishel R, Boothman DA. DNA mismatch repair-dependent response to fluoropyrimidine-generated damage. J Biol Chem 2004; 280:5516-26. [PMID: 15611052 DOI: 10.1074/jbc.m412105200] [Citation(s) in RCA: 98] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Previous studies from our laboratory indicated that expression of the MLH1 DNA mismatch repair (MMR) gene was necessary to restore cytotoxicity and an efficient G(2) arrest in HCT116 human colon cancer cells, as well as Mlh1(-/-) murine embryonic fibroblasts, after treatment with 5-fluoro-2'-deoxyuridine (FdUrd). Here, we show that an identical phenomenon occurred when expression of MSH2, the other major MMR gene, was restored in HEC59 human endometrial carcinoma cells or was present in adenovirus E1A-immortalized Msh2(+/+) (compared with isogenic Msh2(-/-)) murine embryonic stem cells. Because MMR status had little effect on cellular responses (i.e. G(2) arrest and lethality) to the thymidylate synthase inhibitor, Tomudex, and a greater level of [(3)H]FdUrd incorporation into DNA was found in MMR-deficient cells, we concluded that the differential FdUrd cytotoxicity between MMR-competent and MMR-deficient cells was mediated at the level of DNA incorporation. Analyses of ATPase activation suggested that the hMSH2-hMSH6 heterodimer only recognized FdUrd moieties (as the base 5-fluorouracil (FU) in DNA) when mispaired with guanine, but not paired with adenine. Furthermore, analyses of incorporated FdUrd using methyl-CpG-binding domain 4 glycosylase indicated that there was more misincorporated FU:Gua in the DNA of MMR-deficient HCT116 cells. Our data provide the first demonstration that MMR specifically detects FU:Gua (in the first round of DNA replication), signaling a sustained G(2) arrest and lethality.
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Affiliation(s)
- Mark Meyers
- Department of Radiation Oncology and Case Comprehensive Cancer Center, Laboratory of Molecular Stress Responses, Case Western Reserve University, Cleveland, OH 44106, USA
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26
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Corban-Wilhelm H, Ehemann V, Becker G, Greulich D, Braun K, Debus J. Comparison of different methods to assess the cytotoxic effects of cytosine deaminase and thymidine kinase gene therapy. Cancer Gene Ther 2004; 11:208-14. [PMID: 14671673 DOI: 10.1038/sj.cgt.7700667] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Dunning R3327 AT-1 rat prostate tumor cells were transfected with a double-fusion suicide gene (CDglyTK) that coded for the cytosine deaminase from E. coli and the thymidine kinase (TK) from HSV-1. The resulting cell line AT-1/CDglyTK was incubated with 10 and 20 microg/ml 5-FC or 0.25 microg/ml GCV, or both 5-FC and GCV 96 hours before harvest. The MTS assay detected cell viabilities of 50+/-5 and 25+/-5% after 5-FC treatment, and 50+/-5% after GCV treatment. The dye exclusion and the colony-forming assay confirmed the data of the MTS assay with GCV (47+/-5 and 32+/-5%), but presented different results for the 5-FC incubation. We detected 100+/-1 and 85+/-5% viable cells after 10 microg/ml 5-FC, and 97+/-1 and 85+/-5% after 20 microg/ml 5-FC treatment, respectively. S-phase arrest in both suicide gene systems was noticeable and a significant increase in cell granularity was observed after incubation with GCV or GCV & 5-FC. This study demonstrates that 5-FC and the metabolized 5-FU act not only as genotoxic reagents, but also as RNA-directed agent, because of the recovery of the cells. On the other hand, a significant S-phase block could be observed after 24 hours incubation with GCV. This short time is enough to incorporate the genotoxic GCV metabolites in the nascent DNA to impair the cell cycle.
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Affiliation(s)
- Heike Corban-Wilhelm
- Clinical Cooperation Unit Radiotherapeutical Oncology, Deutsches Krebsforschungszentrum (DKFZ), Heidelberg, Germany.
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27
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Ferrer-Orta C, Arias A, Perez-Luque R, Escarmís C, Domingo E, Verdaguer N. Structure of foot-and-mouth disease virus RNA-dependent RNA polymerase and its complex with a template-primer RNA. J Biol Chem 2004; 279:47212-21. [PMID: 15294895 DOI: 10.1074/jbc.m405465200] [Citation(s) in RCA: 178] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Genome replication in picornaviruses is catalyzed by a virally encoded RNA-dependent RNA polymerase, termed 3D. The enzyme performs this operation, together with other viral and probably host proteins, in the cytoplasm of their host cells. The crystal structure of the 3D polymerase of foot-and-mouth disease virus, one of the most important animal pathogens, has been determined unliganded and bound to a template-primer RNA decanucleotide. The enzyme folds in the characteristic fingers, palm and thumb subdomains, with the presence of an NH2-terminal segment that encircles the active site. In the complex, several conserved amino acid side chains bind to the template-primer, likely mediating the initiation of RNA synthesis. The structure provides essential information for studies on RNA replication and the design of antiviral compounds.
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Affiliation(s)
- Cristina Ferrer-Orta
- Institut de Biologia Molecular de Barcelona (CSIC), Parc Científic de Barcelona, Josep Samitier 1-5, E-08028 Barcelona, Spain
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28
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De Bruin M, Van Capel T, Smid K, Fukushima M, Hoekman K, Pinedo HM, Peters GJ. The effect of fluoropyrimidines with or without thymidine phosphorylase inhibitor on the expression of thymidine phosphorylase. Eur J Pharmacol 2004; 491:93-9. [PMID: 15140625 DOI: 10.1016/j.ejphar.2004.03.025] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2004] [Accepted: 03/10/2004] [Indexed: 11/29/2022]
Abstract
Thymidine phosphorylase (platelet-derived-endothelial-cell-growth-factor) catalyzes the reversible phosphorolysis of thymidine to thymine and 2-deoxyribose-1-phosphate, activates 5'-deoxy-5-fluorouridine (5'DFUR) and inactivates trifluorothymidine (TFT). The effect of 5'DFUR and TFT with or without a specific thymidine phosphorylase inhibitor (TPI) on thymidine phosphorylase mRNA, protein expression and activity was studied, in three human colon cancer cell lines, WiDR, HT29 and Lovo exposed for 72 h at IC50 concentrations. In Lovo cells TFT plus TPI only increased thymidine phosphorylase-protein expression 1.7-fold; 5'DFUR and TFT treatment increased thymidine phosphorylase mRNA levels 5- and 1.4-fold, respectively. In WiDR cells, 5'DFUR plus TPI significantly decreased thymidine phosphorylase-protein. TFT and TFT plus TPI increased thymidine phosphorylase-protein 2- and 3-fold, respectively. TPI and 5'DFUR decreased thymidine phosphorylase-mRNA levels significantly. In HT29 cells, 5'DFUR and 5'DFUR plus TPI decreased both thymidine phosphorylase-protein and thymidine phosphorylase-mRNA. In all cell lines 5'DFUR and TFT did not affect thymidine phosphorylase activity, but treatment with TPI (alone or in combination) eliminated thymidine phosphorylase activity. This demonstrated that regulation is drug and cell line dependent.
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Affiliation(s)
- Michiel De Bruin
- Department of Medical Oncology, VU University Medical Center, De Boelelaan 1117, P.O. Box 7057, 1081 HV Amsterdam, The Netherlands
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29
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Meyers M, Hwang A, Wagner MW, Bruening AJ, Veigl ML, Sedwick WD, Boothman DA. A role for DNA mismatch repair in sensing and responding to fluoropyrimidine damage. Oncogene 2003; 22:7376-88. [PMID: 14576845 DOI: 10.1038/sj.onc.1206941] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The phenomenon of damage tolerance, whereby cells incur DNA lesions that are nonlethal, largely ignored, but highly mutagenic, appears to play a key role in carcinogenesis. Typically, these lesions are generated by alkylation of DNA or incorporation of base analogues. This tolerance is usually a result of the loss of specific DNA repair processes, most often DNA mismatch repair (MMR). The availability of genetically matched MMR-deficient and -corrected cell systems allows dissection of the consequences of this unrepaired damage in carcinogenesis as well as the elucidation of cell cycle checkpoint responses and cell death consequences. Recent data indicate that MMR plays an important role in detecting damage caused by fluorinated pyrimidines (FPs) and represents a repair system that is probably not the primary system for detecting damage caused by these agents, but may be an important system for correcting key mutagenic lesions that could initiate carcinogenesis. In fact, clinical studies have shown that there is no benefit of FP-based adjuvant chemotherapy in colon cancer patients exhibiting microsatellite instability, a hallmark of MMR deficiency. MMR-mediated damage tolerance and futile cycle repair processes are discussed, as well as possible strategies using FPs to exploit these systems for improved anticancer therapy.
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Affiliation(s)
- Mark Meyers
- Laboratory of Molecular Stress Responses, Department of Radiation Oncology, Case Western Reserve University, Biomedical Research Building 326-East, 2109 Adelbert Road, Cleveland, OH 44106-4942, USA
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30
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Corban-Wilhelm H, Hull WE, Becker G, Bauder-Wüst U, Greulich D, Debus J. Cytosine deaminase and thymidine kinase gene therapy in a Dunning rat prostate tumour model: absence of bystander effects and characterisation of 5-fluorocytosine metabolism with 19F-NMR spectroscopy. Gene Ther 2002; 9:1564-75. [PMID: 12424609 DOI: 10.1038/sj.gt.3301834] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2002] [Accepted: 06/16/2002] [Indexed: 01/17/2023]
Abstract
The rat prostate tumour cell line R3327 AT-1 was transfected with a gene coding for a fusion protein comprised of cytosine deaminase (CD from E. coli) and thymidine kinase (TK from Herpes simplex virus, HSV-1). The resulting AT-1/CDglyTK cell line was sensitive to the prodrug 5-fluorocytosine (IC(50) = 78 microM, 96-h incubation) via CD and to ganciclovir (GCV, IC(50) = 1 microM, 96 h) via TK. Subcutaneous tumours generated from 100% CDglyTK(+) cells responded well to 5-FC therapy (500 mg/kg, i.p., 14 daily treatments, four out of seven animals in remission) and to GCV therapy (30 mg/kg, i.p., 14 daily treatments, five of six animals in remission). However, experiments with mixtures of CDglyTK(+) and CDglyTK(-) cells showed low levels of connexins (intercellular gap junctions) and no bystander effect for nontransfected cells using either 5-FC or GCV therapy. Furthermore, (19)F-NMR spectroscopy showed that incubation of cultured CDglyTK(+) cells with 774 microM 5-FC for 16 h resulted in the following intracellular concentrations: 5-FC = 314 microM, 5-FU = 52 microM, cytotoxic fluoronucleotides = 163 microM; extracellular 5-FU reached only 6.4 microM. Thus, in this model system intracellular trapping of 5-FU (slow export) contributes to the failure of the CD/5-FC bystander effect via an extracellular route.
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Affiliation(s)
- H Corban-Wilhelm
- Clinical Cooperation Unit, Radiotherapeutical Oncology, Deutsches Krebsforschungszentrum, Heidelberg, Germany
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31
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Malet-Martino M, Martino R. Clinical studies of three oral prodrugs of 5-fluorouracil (capecitabine, UFT, S-1): a review. Oncologist 2002; 7:288-323. [PMID: 12185293 DOI: 10.1634/theoncologist.7-4-288] [Citation(s) in RCA: 272] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Although 5-fluorouracil (5-FU) was first introduced in 1957, it remains an essential part of the treatment of a wide range of solid tumors. 5-FU has antitumor activity against epithelial malignancies arising in the gastrointestinal tract and breast as well as the head and neck, with single-agent response rates of only 10%-30%. Although 5-FU is still the most widely prescribed agent for the treatment of colorectal cancer, less than one-third of patients achieve objective responses. Recent research has focused on the biomodulation of 5-FU to improve the cytotoxicity and therapeutic effectiveness of this drug in the treatment of advanced disease. As all the anticancer agents, 5-FU leads to several toxicities. The toxicity profile of 5-FU is schedule dependent. Myelotoxicity is the major toxic effect in patients receiving bolus doses. Hand-foot syndrome (palmar-plantar erythrodysesthesia), stomatitis, and neuro- and cardiotoxicities are associated with continuous infusions. Other adverse effects associated with both bolus-dose and continuous-infusion regimens include nausea and vomiting, diarrhea, alopecia, and dermatitis. All these reasons explain the need for more effective and less toxic fluoropyrimidines. In the first part of this review, we briefly present the metabolic pathways of 5-FU responsible for the efficacy and toxicity of this drug. This knowledge is also necessary to understand the target(s) of biomodulation. The second part is devoted to a review of the literature on three recent prodrugs of 5-FU, i.e., capecitabine, UFT (ftorafur [FTO] plus uracil), and S-1 (FTO plus 5-chloro-2,4-dihydroxypyridine plus potassium oxonate). The pharmacological principles that have influenced the development of these new drugs and our current knowledge of the clinical pharmacology of these new agents, focusing on antitumor activity and toxicity, are presented. The literature was analyzed until March 2002. This review is intended to be as exhaustive as possible since it was conceived as a work tool for readers wanting to go further.
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Affiliation(s)
- M Malet-Martino
- Groupe de RMN Biomédicale, Laboratoire des IMRCP, Université Paul Sabatier, Toulouse, France.
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Gmeiner WH. The structure and dynamics of the U4/U6 snRNP: implications for pre-mRNA splicing and use as a model system to investigate the RNA-mediated effects of (5F)Ura. J Biomol Struct Dyn 2002; 19:853-62. [PMID: 11922840 DOI: 10.1080/07391102.2002.10506789] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Pre-mRNA splicing is one of the most complex and intricate processes in eukaryotic cell biology. Over the past decade, my laboratory has been interested in determining the structures of RNA components of the spliceosome, and in investigating how the structure, stability and dynamics of these RNA components are perturbed by nucleoside analog substitution. In particular, we have investigated the U4/U6 snRNA complex as a model system for understanding the biophysical basis for the RNA-mediated effects of the widely-used anticancer drug 5-fluorouracil ((5F)Ura). In this review, our studies that have provided novel information concerning the structure of U4 snRNA and its interactions with U6 snRNA and the Sm (or common) snRNA binding proteins are summarized. These studies have also quantified the structural and thermodynamic consequences of (5F)Ura in this model system. Our work to date provides the foundation on which future studies investigating the biophysical basis for spliceosomal assembly and for clarifying the mechanisms of anticancer drugs targeted at nucleic acid-mediated processes will be developed.
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Affiliation(s)
- William H Gmeiner
- Department of Biochemistry,Wake Forest University School of Medicine, Medical Center Boulevard, Winston-Salem, NC 27157, USA.
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Habara K, Ajiki T, Kamigaki T, Nakamura T, Kuroda Y. High expression of thymidylate synthase leads to resistance to 5-fluorouracil in biliary tract carcinoma in vitro. Jpn J Cancer Res 2001; 92:1127-32. [PMID: 11676864 PMCID: PMC5926613 DOI: 10.1111/j.1349-7006.2001.tb01068.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
To evaluate the effect of chemotherapy of 5-fluorouracil (5-FU) in human biliary tract carcinoma, we studied 5-FU sensitivity, thymidylate synthase (TS) content, and dihydropyrimidine dehydrogenase (DPD) activity in 4 human biliary tract carcinoma cell lines compared to 12 various digestive carcinoma cell lines of human organs in vitro. 5-FU sensitivity in the cell lines was analyzed by MTT assay. TS content was analyzed by the [6-(3)H]FdUMP binding assay method, and DPD activity was analyzed by thin-layer chromatography (TLC). 5-FU IC(50) values of biliary tract carcinoma cell lines were significantly higher than those of the carcinoma cell lines of the other digestive organs: 97, 45, 119, and 194 times the concentration of the other digestive, pancreas, colon, and gastric carcinoma cell lines, respectively. TS content of biliary tract carcinoma cell lines was also significantly greater than that of the carcinoma cell lines of the other organs. No difference in DPD activity, however, was recognized between the carcinoma cell lines of each organ. TS content in the cell lines significantly correlated with 5-FU sensitivity, but DPD activity did not. Therefore, in the present study, TS expression was concluded to influence the high resistance to 5-FU of biliary tract carcinoma in comparison with the carcinomas of the other digestive organs.
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Affiliation(s)
- K Habara
- First Department of Surgery, Kobe University School of Medicine, Chuo-ku, Kobe 650-0017.
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Chmura SJ, Gupta N, Advani SJ, Kufe DW, Weichselbaum RR. Prospects for viral-based strategies enhancing the anti-tumor effects of ionizing radiation. Semin Radiat Oncol 2001; 11:338-45. [PMID: 11677658 DOI: 10.1053/srao.2001.26019] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Ionizing radiation (IR) has been extensively used to treat a variety of solid tumors to improve local control and overall survival in patients. Gene therapy strategies represent one experimental direction to improve radiocurability. These gene therapy strategies include (1) replacement of mutated or deleted tumor-suppressor genes, (2) delivery of prodrugs, (3) transduction of genes under the control of radiation-inducible promoters, and (4) genetically engineered viruses that replicate preferentially in tumor cells after IR. Although any one of these viral-based gene therapy approaches is unlikely to succeed independently, experimental results suggest that clinically important antitumor can be achieved when these strategies are combined with IR. Several of these strategies are currently being or soon will be evaluated in clinical trials. This review focuses on molecular mechanisms and potential clinical application of these viral-based gene therapy strategies to improve the therapeutic index of IR.
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Affiliation(s)
- S J Chmura
- Department of Radiation and Cellular Oncology, University of Chicago, Chicago, IL 60637, USA
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Liu J, Kolar C, Lawson TA, Gmeiner WH. Targeted drug delivery to chemoresistant cells: folic acid derivatization of FdUMP[10] enhances cytotoxicity toward 5-FU-resistant human colorectal tumor cells. J Org Chem 2001; 66:5655-63. [PMID: 11511236 DOI: 10.1021/jo005757n] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Current chemotherapy protocols that include fluoropyrimidines, such as 5-fluorouracil (5-FU), are limited by the development of chemoresistance during the course of treatment. Our laboratory has developed a novel class of fluoropyrimidines, FdUMP[N], that are oligodeoxynucleotides (ODNs) composed of some number, N, of 5-fluoro-2'-deoxyuridine-5'-O-monphosphate (FdUMP) nucleotides. Novel synthetic procedures are described that permit conjugation of folic acid to the 5'-OH of FdUMP[10] via a phosphodiester linkage using automated synthesis. The synthetic methods developed are generally applicable for ODN conjugation with folic acid. The folic acid conjugate FA-FdUMP[10] showed improved cytotoxicity toward human colorectal tumor cells (H630), and 5-FU-resistant colorectal tumor cells (H630-10). Enhanced cytotoxicity was observed for FA-FdUMP[10] relative to nonconjugated FdUMP[10] for cells grown under folate-restricted conditions, consistent with cellular uptake being, in part, receptor-mediated. Folate receptor alpha (FRalpha) mRNA was shown by RT-PCR to be overexpressed 26.3-fold in 5-FU-resistant H630-10 cells relative to H630 cells. Thus, FA-FdUMP[N] may prove useful for the treatment of 5-FU-resistant malignancies.
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Affiliation(s)
- J Liu
- Eppley Institute, University of Nebraska Medical Center, Omaha, Nebraska 68198-6805, USA
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36
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Rosty C, Chazal M, Etienne MC, Letoublon C, Bourgeon A, Delpero JR, Pezet D, Beaune P, Laurent-Puig P, Milano G. Determination of microsatellite instability, p53 and K-RAS mutations in hepatic metastases from patients with colorectal cancer: relationship with response to 5-fluorouracil and survival. Int J Cancer 2001; 95:162-7. [PMID: 11307149 DOI: 10.1002/1097-0215(20010520)95:3<162::aid-ijc1028>3.0.co;2-j] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
In vitro and clinical studies have suggested that high-frequency microsatellite instability (MSI-H) phenotype, p53 and K-ras mutations might influence the response to chemotherapy in a variety of tumors, including primary colorectal cancers (CRC). Unresectable hepatic metastases from CRC are commonly treated with 5-fluorouracil (5FU) and folinic acid. Since several new active drugs are now used for treating CRC, molecular determinants predictive to response to 5FU would thus be crucial for optimizing indications of chemotherapy to those patients. MSI-H phenotype, p53 and K-ras status were characterized in a prospective study of 56 patients with CRC metastatic to the liver and treated with 5FU-based chemotherapy. The objective response rate after a 3-month treatment was 32.1%. The prevalence of p53 mutations, K-ras mutations and MSI-H phenotype was 62.5%, 30.3% and 1.8%, respectively. No significant association was found between response to chemotherapy and p53 mutations (78% mutated tumors in responders vs. 55% in nonresponders; p = 0.10) and K-ras mutations (39% mutated tumors in responders vs. 26% in nonresponders; p = 0.34). Survival was longer for patients with p53-mutated metastases than for patients with unresected wild-type p53 metastases (median survival 15 months vs. 17 months; p = 0.06). The determination of the MSI-H phenotype, p53 and K-ras status in hepatic metastases from CRC does not discriminate a group of patients that should preferentially benefit from 5FU-based chemotherapy. The prognosis of patients with treated liver metastases is better when p53 is mutated.
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Affiliation(s)
- C Rosty
- Laboratoire de Toxicologie Moléculaire, INSERM U490, Faculté de Médecine des Saints-Pères, 45 Rue des Saints-Pères, 75270 Paris Cedex 06, France
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Ciccolini J, Peillard L, Aubert C, Formento P, Milano G, Catalin J. Monitoring of the intracellular activation of 5-fluorouracil to deoxyribonucleotides in HT29 human colon cell line: application to modulation of metabolism and cytotoxicity study. Fundam Clin Pharmacol 2000; 14:147-54. [PMID: 10796062 DOI: 10.1111/j.1472-8206.2000.tb00403.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
An HPLC method was developed for in vitro detection and monitoring of intracellular metabolites of [3H]-5-fluorouracil (FUra). Results showed a preferential activation of FUra to ribonucleoside and ribonucleotide derivatives (FURd, FUMP, FUDP and FUTP) in the human colorectal HT29 cell line. We screened various agents so as to determine if they could act as modulators of metabolism and/or toxicity of FUra by reversing the activation pathway of FUra from ribo- to deoxyribonucleotides, thus enhancing FdUMP formation. Different drugs (efflux inhibitors, catabolism inhibitors and enzymatic cofactors) were tested for enhancement of cytotoxicity when associated with FUra. The most promising agents were further studied by assessment of their ability to modulate intracellular activation of FUra to enhance thymidylate synthase (TS) inhibition by FUra and to increase the subsequent induction of apoptosis. 2'-Deoxyinosine (d-Ino), a deoxyribose 1-phosphate donor increasing thymidine phosphorylase activity, stood out as the best modulating agent we screened. Results showed an up to 30-fold increase of cytotoxicity along with a stronger inhibition of TS when FUra was associated with d-Ino, while FUra alone exhibited a lesser effect on TS activity. Besides, HPLC analysis revealed a complete reversal of the activation pathway of FUra, thus leading to an intracellular accumulation of deoxyribonucleotides. Assessment of cell cycle distribution showed a marked increase (+480%) of apoptosis in cells exposed to FUra/d-Ino compared to FUra alone. The HPLC method we developed is a convenient tool for assessing to what extent modulators will actually act on the intracellular activation of FUra. This study confirms the potentiality of d-Ino to modulate FUra metabolism in vitro. It proved to be an agent able to orientate the mechanism of action of FUra towards the inhibition of TS in cells where the normal activation pathway of the drug does not result in the intracellular accumulation of the active metabolite FdUMP.
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Affiliation(s)
- J Ciccolini
- Laboratoire de toxicocinétique et pharmacocinétique, faculté de pharmacie, Marseilles, France.
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Toyoda K, Shibutani M, Sato H, Uneyama C, Takahashi M, Hayashi Y, Hirose M. Lack of carcinogenicity and increased survival in F344 rats treated with 5-fluorouracil for two years. Food Chem Toxicol 2000; 38:187-93. [PMID: 10717359 DOI: 10.1016/s0278-6915(99)00149-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The carcinogenicity of 5-fluorouracil (5-FU), a compound employed as an antineoplastic drug, was investigated in F344 rats of both sexes. 5-FU was administered to groups of 50 male and 50 female rats ad lib. for 104 weeks, added to drinking water at concentrations of 0 (control), 62 and 125 ppm, these dose levels being selected on the basis of results of a 13-week subchronic toxicity study. Body weight gains were slightly depressed in the 125 ppm group of both sexes. While not statistically significant in females, final survival rates at week 111 in the 125 ppm group of both sexes were higher than those in the control group, suggesting an ability of 5-FU to prolong the lifespan. Histopathologically, a decreased incidence of islet cell adenomas in males and increased incidences of pituitary gland adenomas and pheochromocytomas in females were observed in the 62 ppm group without dose dependence. There was no significant induction of any other neoplastic or non-neoplastic lesions. These results indicate a lack of carcinogenicity of 5-FU under the present experimental conditions using rats.
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Affiliation(s)
- K Toyoda
- Division of Pathology, National Institute of Health Sciences, 1-18-1 Kamiyoga, Setagaya-ku, Tokyo, Japan.
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Chmura SJ, Advani SJ, Kufe DW, Weichselbaum RR. Strategies for enhancing viral-based gene therapy using ionizing radiation. RADIATION ONCOLOGY INVESTIGATIONS 1999; 7:261-9. [PMID: 10580895 DOI: 10.1002/(sici)1520-6823(1999)7:5<261::aid-roi1>3.0.co;2-v] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Many gene-therapy strategies under investigation aim to increase the efficacy of current cancer-treatment regimens. Promising results have been obtained in the laboratory and early clinical trials using viral-based motifs specifically designed to enhance the efficacy of ionizing radiation or chemotherapy. These strategies fall into two general categories: replication-incompetent viral shuttle vectors for the delivery of specific genes encoding a chemo/radiation modulator and attenuated replication-competent viruses with proposed replicative advantages in tumor cells. In this review, we discuss the rational, molecular mechanisms, and clinical application of these strategies with particular focus on recent research applying these viral-based strategies to improve the therapeutic index of ionizing radiation.
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Affiliation(s)
- S J Chmura
- Department of Radiation and Cellular Oncology, University of Chicago and the Pritzker School of Medicine, Illinois, USA
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40
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Liu J, Kolath J, Anderson J, Kolar C, Lawson TA, Talmadge J, Gmeiner WH. Positive interaction between 5-FU and FdUMP[10] in the inhibition of human colorectal tumor cell proliferation. ANTISENSE & NUCLEIC ACID DRUG DEVELOPMENT 1999; 9:481-6. [PMID: 10555156 DOI: 10.1089/oli.1.1999.9.481] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Interaction between 5-fluorouracil (5-FU) and FdUMP[10], a novel pro-drug formulation of the thymidylate synthase (TS) inhibitory nucleotide 5-fluoro-2'-deoxyuridine-5'-O-monophosphate (FdUMP), was investigated to evaluate the feasibility of using these two forms of fluorinated pyrimidine in combination chemotherapy regimens. 5-FU and FdUMP[10] are expected to differ in their relative intracellular distribution of active metabolites, and their combined administration may result in either a positive or a negative interactive effect. The dose-response behaviors of 5-FU and FdUMP[10] toward H630 and H630-10 (human colorectal tumor) cells were first investigated separately. Effects on cell viability were measured using an assay for 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), while cytotoxicity and apoptosis were investigated using clonogenic and TUNEL assays, respectively. Exposure of H630 cells to concentrations of FdUMP[10] insufficient to inhibit cell proliferation as a single agent markedly increased the cytotoxicity of 5-FU. The results indicate that 5-FU and FdUMP[10] interact in a positive manner, and that combining these two forms of fluorinated pyrimidine may be clinically beneficial.
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Affiliation(s)
- J Liu
- Eppley Institute, and Department of Pharmaceutical Sciences, University of Nebraska Medical Center, Omaha 68198-6805, USA
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41
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Ackland SP, Peters GJ. Thymidine phosphorylase: its role in sensitivity and resistance to anticancer drugs. Drug Resist Updat 1999; 2:205-214. [PMID: 11504493 DOI: 10.1054/drup.1999.0089] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Thymidine phosphorylase (TP) is an angiogenic enzyme present in normal tissues. Increased levels are found in many tumors, in stromal cells, tumor cells or both. High tumor TP levels may confer a poor prognosis. Cytokines (including interferons), tissue hypoxia and low pH increase TP levels. The influence of tumor TP on fluoropyrimidine toxicity is variable, but capecitabine is a prodrug of fluorouracil that requires activation by TP and hence may have a higher therapeutic index than other fluoropyrimidines. Folate-based thymidylate synthase inhibitors may also be more effective in tumors with a high TP because of increased degradation of endogenous thymidine. Copyright 1999 Harcourt Publishers Ltd.
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Affiliation(s)
- Stephen P. Ackland
- Department of Medical Oncology, Newcastle Mater Misericordiae Hospital, NSW, Australia
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42
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Liu J, Skradis A, Kolar C, Kolath J, Anderson J, Lawson T, Talmadge J, Gmeiner WH. Increased cytotoxicity and decreased in vivo toxicity of FdUMP[10] relative to 5-FU. NUCLEOSIDES & NUCLEOTIDES 1999; 18:1789-802. [PMID: 10478484 DOI: 10.1080/07328319908044843] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
The efficacy of treatment with 5-Fluorouracil (5-FU) is limited, in part, by its inefficient conversion to 5-Fluoro-2'-deoxyuridine-5'-O-monophosphate (FdUMP). We present data indicating that FdUMP[10], designed as a pro-drug for intracellular release of FdUMP, is cytotoxic as a consequence of uptake of the multimeric form. FdUMP[10] is stable in cell culture medium, with more than one-half of the material persisting as multimers of at least six nucleotides after a 48 h incubation at 37 degrees C. FdUMP[10] is more than 400 times more cytotoxic than 5-FU towards human colorectal tumor cells (H630). FdUMP[10] also has decreased toxicity in vivo, with doses as high as 200 mg/kg/day (qdx3) administered to Balb/c mice without morbidity, compared to a maximum tolerated dose of 45 mg/kg/day for 5-FU using the same protocol. FdUMP[10] shows reduced sensitivity to OPRTase- and TK-mediated drug resistance, relative to 5-FU and FdU, respectively, and is much more cytotoxic than 5-FU towards cells that overexpress thymidylate synthase. Thus, FdUMP[10] is less susceptible to resistance mechanisms that limit the clinical utility of 5-FU. The increased cytotoxicity, decreased toxicity in vivo, and reduced sensitivity to drug resistance of FdUMP[10], relative to 5-FU, indicates multimeric FdUMP is potentially valuable as an anti-neoplastic agent, either as a single agent, or in combination with 5-FU.
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Affiliation(s)
- J Liu
- Eppley Institute, University of Nebraska Medical Center, Omaha 68198-6805, USA
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43
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Lutz NW, Hull WE. Assignment and pH dependence of the 19F-NMR resonances from the fluorouracil anabolites involved in fluoropyrimidine chemotherapy. NMR IN BIOMEDICINE 1999; 12:237-248. [PMID: 10421915 DOI: 10.1002/(sici)1099-1492(199906)12:4<237::aid-nbm565>3.0.co;2-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Fluoropyrimidine chemotherapy relies on the intracellular anabolic conversion of 5-fluorouracil and the corresponding nucleosides to cytotoxic fluorinated nucleotides (F-Nuctd), such as 5-fluorouridine-5'-triphosphate (FUTP) or 5-fluoro-2'-deoxyuridine-5'-monophosphate (FdUMP), which can be detected by 19F-NMR spectroscopy. We have made 19F-NMR signal assignments at 11.7 T and 4 degrees C for model solutions containing 5-fluorouracil (FUra), 5-fluorouridine (FUrd), 5-fluoro-2'-deoxyuridine (FdUrd), 5-fluorouridine-5'-monophosphate (FUMP), FdUMP, 5-fluorouridine-5'-diphosphate (FUDP), FUTP and 5-fluorouridine-5'-diphospho(1)-alpha-D-glucose (FUDPG), and we have studied the effects of pH over the range 4.5-7.8, of Mg2+ concentration and addition of EDTA. This information provides a basis for the analysis of 19F-NMR spectra obtained from cells, tissues or extracts following fluoropyrimidine treatment.
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Affiliation(s)
- N W Lutz
- Central Spectroscopy Department, German Cancer Research Center, Heidelberg
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44
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Chen TB, Bajzer Z, Macura S, Vuk-Pavlovic S. Differences in metabolism of 5-fluorouracil and 5-fluorouridine and regulation by glucosamine in human colon cancer multicell tumor spheroids. NMR IN BIOMEDICINE 1999; 12:157-167. [PMID: 10414950 DOI: 10.1002/(sici)1099-1492(199905)12:3<157::aid-nbm551>3.0.co;2-i] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Glucosamine (GlcN) modulates fluoropyrimidine metabolism and enhances cytotoxicity of 5-fluorouridine (FUrd), but not of 5-fluorouracil (FUra), in human tumor models. To elucidate the underlying metabolic differences between FUra and FUrd, by the use of 19F and 31P NMR spectroscopy we studied these drugs in multicell tumor spheroids (MTS) formed by human colon carcinoma cells HT-29. This experimental system allowed detailed kinetic measurements of anabolic intracellular phosphates and fluorophosphates over periods of up to 2 days. Time-dependent NMR data were reduced and interpreted by the use of nonlinear compartmental models which yielded numerical values for the empirical rate constants characterizing mass transfer among the compartments. An analysis of these rate constants indicated qualitative and quantitative differences in the metabolism of FUra and FUrd and in the effects of GlcN on these drugs. The enhanced generation of FUDP-hexoses was a predicted effect of GlcN, but inhibited formation of fluorouridine diphosphates and fluorouridine triphosphates in FUra-treated MTS, and the magnitude of stimulation of fluoropyrimidine incorporation into macromolecules in FUrd-treated MTS were not predicted.
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Affiliation(s)
- T B Chen
- Department of Oncology, Mayo Clinic and Mayo Foundation, Rochester, MN 55905, USA
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45
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Marbach P, Bauer W, Bodmer D, Briner U, Bruns C, Kay A, Lancranjan I, Pless J, Raulf F, Robison R, Sharkey J, Soranno T, Stolz B, Vit P, Weckbecker G. Discovery and development of somatostatin agonists. PHARMACEUTICAL BIOTECHNOLOGY 1998; 11:183-209. [PMID: 9760681 DOI: 10.1007/0-306-47384-4_9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Affiliation(s)
- P Marbach
- Novartis Pharma AG, Basel, Switzerland
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46
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Gabel M, Kim JH, Kolozsvary A, Khil M, Freytag S. Selective in vivo radiosensitization by 5-fluorocytosine of human colorectal carcinoma cells transduced with the E. coli cytosine deaminase (CD) gene. Int J Radiat Oncol Biol Phys 1998; 41:883-7. [PMID: 9652853 DOI: 10.1016/s0360-3016(98)00125-4] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
PURPOSE The E. coli cytosine deaminase (CD) gene encodes an enzyme capable of converting the nontoxic prodrug 5-fluorocytosine (5-FC) to 5-fluorouracil (5-FU), a known radiosensitizer. Having previously shown that combined CD suicide gene therapy and radiation (RT) results in pronounced radiosensitization in vitro, we progressed to in vivo studies of combined therapy. METHODS AND MATERIALS WiDr human colon cancer cells were transduced in vitro with the CD gene and cells expressing CD were selected for use as xenografts in a nude mouse model. After administration of 5-FC, tumors received 10-30 Gy local field radiation (RT) and tumor growth delay was compared to control animals receiving either 5-FU, 5-FC, or RT alone. RESULTS Maximal growth delay was seen in mice treated with 5-FC for 6 consecutive days prior to RT. Combined treatment with 15 Gy radiation resulted in a dose-modifying factor (DMF) of 1.50, and a greater DMF was observed with higher doses of radiation. There was no appreciable toxicity using this new approach. In contrast, a similar treatment of combined 5-FU and radiation resulted in considerable toxicity and no appreciable radiosensitization. CONCLUSION The present results show that combined suicide gene therapy and RT results in pronounced antitumor effect without any notable toxicity. This indicates that the CD gene may be useful in the development of novel treatment strategies combining radiation and gene therapy in the treatment of locally advanced cancers.
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Affiliation(s)
- M Gabel
- Department of Radiation Oncology, Henry Ford Hospital, Detroit, MI 48202, USA
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47
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van Laar JA, Rustum YM, Ackland SP, van Groeningen CJ, Peters GJ. Comparison of 5-fluoro-2'-deoxyuridine with 5-fluorouracil and their role in the treatment of colorectal cancer. Eur J Cancer 1998; 34:296-306. [PMID: 9640213 DOI: 10.1016/s0959-8049(97)00366-3] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Despite more than 30 years of intensive studies on new drugs against advanced colorectal cancer, the fluoropyrimidines remain the drugs of choice for systemic treatment and for hepatic artery infusion (HAI). This overview describes new developments in advanced colorectal cancer chemotherapy, providing a rationale for more effective use of the fluoropyrimidines, with biochemical modulation, scheduling or by revealing biochemical mechanisms of action that correlate with antitumour activity. In human colorectal cancer cell lines and various animal tumour model systems 5-fluoro-2'-deoxyuridine (FdUrd) is more effective than 5-fluorouracil (5-FU). Comparably, FdUrd's modulation by leucovorin (LV) is more potent than 5-FU. In animal studies it is shown that intermittent high-bolus administration of FdUrd generates better antitumour activity, compared with equal toxic doses or any other schedule of 5-FU. These effects are related to prolonged-thymidylate synthase (TS) inhibition and the prevention of TS induction, rather than RNA incorporation. Preclinical studies with modulators such as N-phosphonacetyl-L-aspartate (PALA), WR-2721, mitomycin C and platinum derivatives provide a rationale for clinical use in the future. The first choice systemic chemotherapy of patients with advanced colorectal cancer remains 5-FU combined with LV. Some improvement in therapeutic efficacy has been achieved with locoregional HAI. In randomised studies HAI FdUrd improves the quality of life and survival as compared with optimal systemic therapy. Chronomodulation decreases toxicity, allowing dose intensification, while modulators such as LV or dexamethasone increase survival of patients treated with HAI FdUrd to 86% after 1 year. In conclusion, the clinical use of FdUrd has not been fully explored. Intermittent high-dose FdUrd, chronomodulation together with the use of modulators or drugs focused on prolonged TS inhibition, should be studied in large randomised studies.
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Affiliation(s)
- J A van Laar
- Department of Medical Oncology, University Hospital VU, Amsterdam, The Netherlands
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Leccia JR, Milano G, Formento P, Francoual M, Formento JL, Pierrefite V. A clinically applicable assay for tumoral thymidylate synthase combining reverse transcriptase-PCR and high-performance liquid chromatography. Eur J Cancer 1998; 34:182-7. [PMID: 9624255 DOI: 10.1016/s0959-8049(97)00368-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The main clinically relevant cellular target of 5-fluorouracil (5-FU) is the enzyme thymidylate synthase (TS). Both preclinical data and clinical data in digestive tract cancer indicate that an increased amount of TS in tumours can predict for 5-FU resistance. We developed an automated method combining the principle of RT-PCR coupled with HPLC separation and quantification. The RT-PCR HPLC method was applied to TS determination in tumoral biopsies from patients with colorectal cancer. The PCR samples were separated and quantified using a polystyrene divinylbenzene C 18 column. Within 22 min, it was possible to elute 18 peaks representing DNA sizes ranging from 34 to 622 bp. Both separation and quantification of beta 2 microglobulin (beta 2m, internal standard) and TS PCR products were achieved in approximately 10 min per sample. Validation of the RT-PCR HPLC method was established by comparing RT-PCR quantification of TS after electrophoresis and HPLC and by comparing the RT-PCR quantification of TS after HPLC with the classical biochemical method. The proposed HPLC method offers a 10-50 fold sensitivity advantage over electrophoresis. In addition, this RT-PCR HPLC procedure allows not only the quantification of TS expression but also the direct collection of unaltered amplified DNA sequence which could be useful for sequencing analysis, since TS mutations have been described. The present RT-PCR HPLC method for determining TS expression in tumoral biopsies is a valuable analytical approach as it is specific, sensitive and clinically applicable.
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Affiliation(s)
- J R Leccia
- Oncopharmacology Department, Centre Antoine Lacassagne, Nice, France
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Furuya Y, Yamamoto K, Kohno N, Yamamoto M, Saitoh Y. Nocturnal 5-fluorouracil infusion to patients with breast cancer prior to surgery: appearance of 5-fluorouracil-induced AgNORs aggregation (FAA). Cancer Lett 1997; 116:79-84. [PMID: 9177461 DOI: 10.1016/s0304-3835(97)00163-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Between 1994 and 1995, 1 day nocturnal infusion of 5-fluorouracil (5-FU) was performed prior to surgery in 13 primary breast cancer patients; 300 mg/m2 of 5-FU was infused constantly from 2100 h to 0700 h via peripheral vein with a volumetric pump. 5-FU concentration in tissues was measured within surgical specimens by HPLC. The concentrations of 5-FU in tumor tissues ranged from 6 to 49 ng/g (average +/- SEM 25.0 +/- 4.1 ng/g), while in normal breast tissues and adipose tissues 5-FU was below the detection limit (<3 ng/g). The 5-FU concentration was lower in estrogen-receptor-positive tumors (14.4 +/- 4.5 ng/g) than in estrogen-receptor-negative tumors (31.8 +/- 5.0 ng/g). Typical FAA was observed in the tumor tissues of three patients. In these three cases, AgNORs were aggregated to one large spheroidal figure in more than 39% of tumor cells. Appearance of FAA could not be predicted by other clinical features. Nocturnal 5-FU infusion caused FAA changes in certain types of primary breast cancer.
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Affiliation(s)
- Y Furuya
- First Department of Surgery, Kobe University School of Medicine, Chuo-ku, Japan
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Ghoshal K, Jacob ST. An alternative molecular mechanism of action of 5-fluorouracil, a potent anticancer drug. Biochem Pharmacol 1997; 53:1569-75. [PMID: 9264308 DOI: 10.1016/s0006-2952(97)00040-3] [Citation(s) in RCA: 114] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
It is assumed that the primary mode of action of 5-fluorouracil (5-FUra) is mediated via inhibition of thymidylate synthetase. Persistent inhibition of cellular proliferation after treatment of the 5-FUra-inhibited cells with exogenous thymidine do not support the notion that the anti-proliferitive action of 5-FUra is due exclusively to inhibition of DNA replication. Our studies have revealed an alternative mechanism of action at the level of pre-ribosomal RNA (pre-rRNA) processing. Pre-rRNA processing was inhibited completely in vitro as well as in S-100 extract from the mouse lymphosarcoma P1798 cells that were treated with 5-FUra. Under this condition, the 5-FUra-substituted pre-rRNA substrate was processed efficiently at the primary processing site. This study showed that the activity and/or the synthesis of a factor potentially involved in pre-rRNA processing is blocked in cells treated with the fluoropyrimidine. UV-cross-linking study showed that a 200 kDa polypeptide designated ribosomal RNA binding protein (RRBP) was absent in the S-100 extract from the drug-treated mouse lymphosarcoma cells. Since a polypeptide that cross-links to a processing site on RNA is usually involved in the RNA processing, RRBP may have a direct role in pre-rRNA processing. A key molecular mechanism far the antiproliferative action of 5-FUra may be due to its interference with the activity and/or synthesis of RRBP. Exposure of cells to 5-FUra did not inhibit the interaction between U3 small nucleolar RNA (snoRNA) and pre-rRNA at the primary processing site (a key step in the processing reaction) and the formation of U3 small nucleolar ribonucleoprotein (snoRNP). Treatment of cells with the fluoropyrimidine did not block the 3' end processing of pre-messenger RNA (pre-mRNA). This article also discusses the effects of 5-FUra on pre-mRNA splicing and mRNA translation, and proposes other avenues of research to explore further the mechanism of action of this important pyrimidine analog.
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Affiliation(s)
- K Ghoshal
- Department of Pharmacology and Molecular Biology, The Chicago Medical School, North Chicago, IL 60064, USA
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