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Caputo WL, de Souza MC, Basso CR, Pedrosa VDA, Seiva FRF. Comprehensive Profiling and Therapeutic Insights into Differentially Expressed Genes in Hepatocellular Carcinoma. Cancers (Basel) 2023; 15:5653. [PMID: 38067357 PMCID: PMC10705715 DOI: 10.3390/cancers15235653] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Revised: 11/02/2023] [Accepted: 11/04/2023] [Indexed: 02/16/2024] Open
Abstract
Background: Drug repurposing is a strategy that complements the conventional approach of developing new drugs. Hepatocellular carcinoma (HCC) is a highly prevalent type of liver cancer, necessitating an in-depth understanding of the underlying molecular alterations for improved treatment. Methods: We searched for a vast array of microarray experiments in addition to RNA-seq data. Through rigorous filtering processes, we have identified highly representative differentially expressed genes (DEGs) between tumor and non-tumor liver tissues and identified a distinct class of possible new candidate drugs. Results: Functional enrichment analysis revealed distinct biological processes associated with metal ions, including zinc, cadmium, and copper, potentially implicating chronic metal ion exposure in tumorigenesis. Conversely, up-regulated genes are associated with mitotic events and kinase activities, aligning with the relevance of kinases in HCC. To unravel the regulatory networks governing these DEGs, we employed topological analysis methods, identifying 25 hub genes and their regulatory transcription factors. In the pursuit of potential therapeutic options, we explored drug repurposing strategies based on computational approaches, analyzing their potential to reverse the expression patterns of key genes, including AURKA, CCNB1, CDK1, RRM2, and TOP2A. Potential therapeutic chemicals are alvocidib, AT-7519, kenpaullone, PHA-793887, JNJ-7706621, danusertibe, doxorubicin and analogues, mitoxantrone, podofilox, teniposide, and amonafide. Conclusion: This multi-omic study offers a comprehensive view of DEGs in HCC, shedding light on potential therapeutic targets and drug repurposing opportunities.
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Affiliation(s)
- Wesley Ladeira Caputo
- Post Graduation Program in Experimental Pathology, State University of Londrina (UEL), Londrina 86057-970, PR, Brazil; (W.L.C.); (M.C.d.S.)
| | - Milena Cremer de Souza
- Post Graduation Program in Experimental Pathology, State University of Londrina (UEL), Londrina 86057-970, PR, Brazil; (W.L.C.); (M.C.d.S.)
| | - Caroline Rodrigues Basso
- Department of Chemical and Biological Sciences, Institute of Bioscience, São Paulo State University (UNESP), Botucatu 18610-034, SP, Brazil; (C.R.B.); (V.d.A.P.)
| | - Valber de Albuquerque Pedrosa
- Department of Chemical and Biological Sciences, Institute of Bioscience, São Paulo State University (UNESP), Botucatu 18610-034, SP, Brazil; (C.R.B.); (V.d.A.P.)
| | - Fábio Rodrigues Ferreira Seiva
- Post Graduation Program in Experimental Pathology, State University of Londrina (UEL), Londrina 86057-970, PR, Brazil; (W.L.C.); (M.C.d.S.)
- Department of Chemical and Biological Sciences, Institute of Bioscience, São Paulo State University (UNESP), Botucatu 18610-034, SP, Brazil; (C.R.B.); (V.d.A.P.)
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Abstract
Background The number of individuals aged 65 years and older is growing rapidly, and the majority of cancers are diagnosed in this age group. Age-related changes in physiology can affect chemotherapy pharmacokinetics and pharmacodynamics in older patients. Methods We review the literature regarding the impact of age on the pharmacokinetics of commonly used chemotherapy drugs and discuss age-related changes in physiology and pharmacology that can affect chemotherapy tolerance in older patients. Results The data on age-related changes in chemotherapy pharmacokinetics are conflicting. While a few studies report age-related differences in chemotherapy pharmacokinetics, most found no significant difference or subtle differences in pharmacokinetics with aging. A difference in pharmacodynamics was commonly seen, however, with older patients at increased risk of myelosuppression and toxicity from age-related decline in organ function. The majority of these studies were performed in a small cohort of patients, thus limiting the generalizability of these results. Conclusions Additional studies are needed to address the pharmacokinetics and pharmacodynamics of cancer therapies in the older patient. Multicenter pharmacokinetic studies of adequate sample size, which include a thorough evaluation of physiologic factors and geriatric assessment parameters, would provide further insight into the factors affecting treatment tolerance. These studies would also help to guide appropriate chemotherapy dosing and interventions in order to maximize efficacy and minimize toxicity in the older patient.
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Affiliation(s)
- Arti Hurria
- Cancer and Aging Research Program, City of Hope National Medical Center, Duarte, CA 91010, USA.
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Yan T, Lu L, Xie C, Chen J, Peng X, Zhu L, Wang Y, Li Q, Shi J, Zhou F, Hu M, Liu Z. Severely Impaired and Dysregulated Cytochrome P450 Expression and Activities in Hepatocellular Carcinoma: Implications for Personalized Treatment in Patients. Mol Cancer Ther 2015; 14:2874-86. [PMID: 26516155 PMCID: PMC4674380 DOI: 10.1158/1535-7163.mct-15-0274] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2015] [Accepted: 09/17/2015] [Indexed: 12/22/2022]
Abstract
This study aims to systematically determine the activities and expressions of cytochrome P450s (CYP) in hepatocellular carcinoma (HCC) patients to support their optimal use in personalized treatment of HCC. Activities of seven major drug-metabolizing CYP enzymes (CYP1A2, 2A6, 2C8, 2C9, 2D6, 2E1, and 3A4) were determined in tumors and pericarcinomatous tissues harvested from 26 patients with hepatitis B virus-positive HCC using probe substrates. Protein and mRNA levels of these CYPs were also measured using isotope label-free LC/MS-MS method and real-time PCR, respectively. Maximal metabolic velocity (Vmax) of CYP probe substrates was decreased by 2.5- to 30-fold in tumor microsomes, accompanied by a corresponding decrease in their protein and mRNA expression levels. However, Km values and turnover numbers of substrates in tumor microsomes were not changed. High correlations between activities and CYP protein levels were also observed, but the correlation between activities and mRNA levels was often poor. There was a major decrease in the degree of correlation in CYP expression in tumor tissues, suggesting that CYP expression levels are greatly disrupted by the tumorigenic process. Our unprecedented systemic study of the effects of HCC on CYPs demonstrated that activities of CYPs were seriously impaired and their expression patterns were severely altered by HCC. We proposed that determination of the CYP protein expression profile by LC/MS-MS in each patient is a promising approach that can be clinically used for individualized treatment of HCC.
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Affiliation(s)
- Tongmeng Yan
- Department of Pharmaceutics, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou, Guangdong, China
| | - Linlin Lu
- International Institute for Translational Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, China
| | - Cong Xie
- Department of Pharmaceutics, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou, Guangdong, China
| | - Jiamei Chen
- International Institute for Translational Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, China
| | - Xiaojuan Peng
- Department of Pharmaceutics, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou, Guangdong, China
| | - Lijun Zhu
- International Institute for Translational Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, China
| | - Ying Wang
- International Institute for Translational Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, China
| | - Qiang Li
- Department of Pharmaceutics, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou, Guangdong, China
| | - Jian Shi
- Department of Pharmaceutics, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou, Guangdong, China
| | - Fuyuan Zhou
- Department of Infectious Diseases, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China
| | - Ming Hu
- Department of Pharmacological and Pharmaceutical Sciences, College of Pharmacy, University of Houston, Houston, Texas.
| | - Zhongqiu Liu
- Department of Pharmaceutics, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou, Guangdong, China. International Institute for Translational Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, China.
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Oral treatment with etoposide in small cell lung cancer - dilemmas and solutions. Radiol Oncol 2013; 47:1-13. [PMID: 23450046 PMCID: PMC3573828 DOI: 10.2478/raon-2013-0008] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2012] [Accepted: 11/08/2012] [Indexed: 11/30/2022] Open
Abstract
Background Etoposide is a chemotherapeutic agent, widely used for the treatment of various malignancies, including small cell lung cancer (SCLC), an aggressive disease with poor prognosis. Oral etoposide administration exhibits advantages for the quality of life of the patient as well as economic benefits. However, widespread use of oral etoposide is limited by incomplete and variable bioavailability. Variability in bioavailability was observed both within and between patients. This suggests that some patients may experience suboptimal tumor cytotoxicity, whereas other patients may be at risk for excess toxicity. Conclusions The article highlights dilemmas as well as solutions regarding oral treatment with etoposide by presenting and analyzing relevant literature data. Numerous studies have shown that bioavailability of etoposide is influenced by genetic, physiological and environmental factors. Several strategies were explored to improve bioavailability and to reduce pharmacokinetic variability of oral etoposide, including desired and undesired drug interactions (e.g. with ketoconazole), development of suitable drug delivery systems, use of more water-soluble prodrug of etoposide, and influence on gastric emptying. In addition to genotype-based dose administration, etoposide is suitable for pharmacokinetically guided dosing, which enables dose adjustments in individual patient. Further, it is established that oral and intravenous schedules of etoposide in SCLC patients do not result in significant differences in treatment outcome, while results of toxicity are inconclusive. To conclude, the main message of the article is that better prediction of the pharmacokinetics of oral etoposide may encourage its wider use in routine clinical practice.
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Ukawala M, Rajyaguru T, Chaudhari K, Manjappa AS, Pimple S, Babbar AK, Mathur R, Mishra AK, Murthy RSR. Investigation on design of stable etoposide-loaded PEG-PCL micelles: effect of molecular weight of PEG-PCL diblock copolymer on thein vitroandin vivoperformance of micelles. Drug Deliv 2012; 19:155-67. [DOI: 10.3109/10717544.2012.657721] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Gerritsen-van Schieveen P, Royer B. Level of evidence for therapeutic drug monitoring for etoposide after oral administration. Fundam Clin Pharmacol 2011; 25:277-82. [DOI: 10.1111/j.1472-8206.2010.00856.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Jaundice as a presenting manifestation of pediatric non-Hodgkin lymphoma: etiology, management, and outcome. J Pediatr Hematol Oncol 2010; 32:e131-5. [PMID: 20445407 DOI: 10.1097/mph.0b013e3181d640c5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
OBJECTIVES There are few data available on the management and outcome of pediatric patients with non-Hodgkin lymphoma (NHL) presenting with jaundice. Controversies exist on biliary drainage and chemotherapy dose modifications to be carried out in such patients. The aim of this study was to analyze the causes of jaundice in, the various modalities of treatment administered to, and outcome of patients aged 18 years or less, with de novo NHL and jaundice treated at our center. PATIENTS AND METHODS A retrospective analysis show 9 such cases (11.2% of all NHL cases), all of whom were treated by a uniform protocol. Chemotherapy dose modifications were based on serum bilirubin and clinical status of the patients. RESULTS Obstructive jaundice was the most common cause (7 of 9). Seven patients achieved normal serum bilirubin with chemotherapy alone. Only one had a biliary drainage procedure. Four patients were alive and disease-free at last follow-up. CONCLUSIONS Although biliary obstruction is the commonest most cause of jaundice in pediatric and adolescent NHL, biliary drainage may be unnecessary and chemotherapy alone may suffice as initial treatment for these patients.
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Schieveen PGV, Hulin A, Muret P, Royer B. Niveau de preuve du suivi thérapeutique pharmacologique de l’étoposide administré par voie orale. Therapie 2010; 65:207-12. [DOI: 10.2515/therapie/2010019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2010] [Accepted: 03/03/2010] [Indexed: 11/20/2022]
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P-glycoprotein (P-gp/Abcb1), Abcc2, and Abcc3 Determine the Pharmacokinetics of Etoposide. Clin Cancer Res 2009; 16:130-40. [DOI: 10.1158/1078-0432.ccr-09-1321] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Abstract
This abbreviated review outlines the physiologic changes associated with aging, and examines how these changes may affect the pharmacokinetics and pharmacodynamics of anticancer therapies. We also provide an overview of studies that have been conducted evaluating the pharmacology of anticancer therapies in older adults, and issue a call for further research.
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Affiliation(s)
- A Hurria
- The Department of Medical Oncology and Therapeutics Research, City of Hope, Duarte, CA 91010, USA.
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11
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Superfin D, Iannucci AA, Davies AM. Commentary: Oncologic drugs in patients with organ dysfunction: a summary. Oncologist 2007; 12:1070-83. [PMID: 17914077 DOI: 10.1634/theoncologist.12-9-1070] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
There are few prospective data regarding the pharmacokinetics and clinical toxicity of commonly used chemotherapeutics in cancer patients with organ dysfunction. Although increasing numbers of studies are investigating newer chemotherapeutics in patients with liver or kidney dysfunction, most guidelines for dosing, especially for established agents, remain empiric. This review describes the available data (both prospective and case study) evaluating the impact of renal and hepatic dysfunction on toxicity and dosing of commonly used chemotherapeutics and provides a practical summary for their use in this setting.
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Affiliation(s)
- Diana Superfin
- University of California Davis Cancer Center, 4501 X Street, Sacramento, California 95817, USA
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12
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Ishikawa T, Imai M, Kamimura H, Tsuchiya A, Togashi T, Watanabe K, Seki KI, Ohta H, Yoshida T, Kamimura T. Improved survival for hepatocellular carcinoma with portal vein tumor thrombosis treated by intra-arterial chemotherapy combining etoposide, carboplatin, epirubicin and pharmacokinetic modulating chemotherapy by 5-FU and enteric-coated tegafur/uracil: A pilot study. World J Gastroenterol 2007; 13:5465-70. [PMID: 17907289 PMCID: PMC4171280 DOI: 10.3748/wjg.v13.i41.5465] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To investigate the poor prognosis of HCC with PVTT, we evaluated the efficacy by a new combination chemotherapy for advanced hepatocellular carcinoma (HCC) with portal vein tumor thrombus (PVTT).
METHODS: From 2002 to 2007, a total of 10 consecutive patients with Stage IVA HCC accompanied by PVTT were studied prospectively to examine the efficacy of treatment by intra-arterial infusion of a chemotherapeutic agents consisting of etoposide, carboplatin, epirubicin and pharmacokinetic modulating chemotherapy by 5-FU and enteric-coated tegafur/uracil.
RESULTS: The mean course of chemotherapy was 14.4 (range, 9-21) mo. One patient showed complete response (CR) with disappearance of HCC and PVTT after treatment, and the two patients showed partial response (PR), response rate (CR + PR/All cases 30%). The median survival time after the therapy was 457.2 d. The one-year survival rate was 70%. Adverse reactions were tolerable.
CONCLUSION: Although the prognosis of most patients with Stage IVA HCC by PVTT is poor, our combination chemotherapy may induces long-term survival and is an effective treatment and produced anti-tumor activity with tolerable adverse effects in patients for advanced Stage IVA HCC accompanied by PVTT.
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Affiliation(s)
- Toru Ishikawa
- Department of Gastroenterology and Hepatology, Saiseikai Niigata Second Hospital, Teraji 280-7, Niigata 950-1104, Japan.
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13
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Lichtman SM, Wildiers H, Chatelut E, Steer C, Budman D, Morrison VA, Tranchand B, Shapira I, Aapro M. International Society of Geriatric Oncology Chemotherapy Taskforce: evaluation of chemotherapy in older patients--an analysis of the medical literature. J Clin Oncol 2007; 25:1832-43. [PMID: 17488981 DOI: 10.1200/jco.2007.10.6583] [Citation(s) in RCA: 180] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The elderly comprise the majority of patients with cancer and are the recipients of the greatest amount of chemotherapy. Unfortunately, there is a lack of data to make evidence-based decisions with regard to chemotherapy. This is due to the minimal participation of older patients in clinical trials and that trials have not systematically evaluated chemotherapy. This article reviews the available information with regard to chemotherapy and aging provided by a task force of the International Society of Geriatric Oncology (SIOG). Due to the lack of prospective data, the conclusions and recommendations made are a consensus of the participants. Extrapolation of data from younger to older patients is necessary, particularly to those patients older than 80 years, for which data is almost entirely lacking. The classes of drugs reviewed include alkylators, antimetabolites, anthracyclines, taxanes, camptothecins, and epipodophyllotoxins. Clinical trials need to incorporate an analysis of chemotherapy in terms of the pharmacokinetic and pharmacodynamic effects of aging. In addition, data already accumulated need to be reanalyzed by age to aid in the management of the older cancer patient.
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Affiliation(s)
- Stuart M Lichtman
- Memorial Sloan-Kettering Cancer Center, Commack, New York 11725, USA.
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14
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Yong WP, Desai AA, Innocenti F, Ramirez J, Shepard D, Kobayashi K, House L, Fleming GF, Vogelzang NJ, Schilsky RL, Ratain MJ. Pharmacokinetic modulation of oral etoposide by ketoconazole in patients with advanced cancer. Cancer Chemother Pharmacol 2007; 60:811-9. [PMID: 17308893 DOI: 10.1007/s00280-007-0428-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2006] [Accepted: 01/15/2007] [Indexed: 11/28/2022]
Abstract
PURPOSE Etoposide is a widely used cytotoxic drug that is commercially available in both intravenous and oral formulations. High interpatient pharmacokinetic variability has been associated with oral etoposide administration. Various strategies used in the past to reduce such variability have not been successful. Hence, this study was designed to evaluate if pharmacokinetic modulation of oral etoposide with ketoconazole could lead to a favorable alteration of etoposide pharmacokinetics, and to assess the feasibility and safety of this approach. METHODS Thirty-two patients were treated with ketoconazole 200 mg daily with an escalating dose of oral etoposide starting at a dose of 50 mg every other day. Pharmacokinetic samples were obtained during the first treatment cycle after the administration of an oral etoposide and ketoconazole dose. Additional baseline pharmacokinetic studies of etoposide alone were performed 4 days prior to the first treatment cycle. RESULTS Dose limiting toxicities were neutropenia and fatigue. Ketoconazole increased the area under the plasma concentration-time curve (AUC) of oral etoposide by a median of 20% (p < 0.005). Ketoconazole did not reduce the interpatient variability in etoposide pharmacokinetics. Pretreatment bilirubin levels correlated with etoposide clearance (Spearman's r = -0.48, p = 0.008). The maximum tolerated dose was etoposide administered at 50 mg daily and ketoconazole 200 mg qd for 3 of 5 weeks. CONCLUSIONS Ketoconazole reduces the apparent clearance of oral etoposide, does not alter its toxicity profile and does not reduce interpatient pharmacokinetic variability. Other methods to reduce the pharmacokinetic variability of oral etoposide are needed.
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Affiliation(s)
- Wei Peng Yong
- Committee on Clinical Pharmacology and Pharmacogenomics, University of Chicago, 5841 S Maryland Ave, MC2115, Chicago, IL 60637, USA
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Hartmann JT, Lipp HP. Camptothecin and podophyllotoxin derivatives: inhibitors of topoisomerase I and II - mechanisms of action, pharmacokinetics and toxicity profile. Drug Saf 2007; 29:209-30. [PMID: 16524321 DOI: 10.2165/00002018-200629030-00005] [Citation(s) in RCA: 105] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Camptothecins represent an established class of effective agents that selectively target topoisomerase I by trapping the catalytic intermediate of the topoisomerase I-DNA reaction, the cleavage complex. The water-soluble salt camptothecin-sodium - introduced in early trials in the 1960s - was highly toxic in animals, whereas the semisynthetic derivatives irinotecan and topotecan did not cause haemorrhagic cystitis because of their higher physicochemical stability and solubility at lower pH values. Myelosuppression, neutropenia and, to a lesser extent, thrombocytopenia are dose-limiting toxic effects of topotecan. In contrast to the structurally-related topotecan, irinotecan is a prodrug which has to be converted to SN-38, its active form. SN-38 is inactivated by conjugation, thus patients with Gilbert's syndrome and other forms of genetic glucuronidation deficiency are at an increased risk of irinotecan-induced adverse effects, such as neutropenia and diarrhoea. The cytotoxic mechanism of podophyllotoxin is the inhibition of topoisomerase II. Common adverse effects of etoposide include dose-limiting myelosuppression. Hypersensitivity reactions are more common with etoposide and teniposide than with etoposide phosphate because the formulations of the former contain sensitising solubilisers. Leukopenia and thrombocytopenia occur in 65% and 80%, respectively, of patients after administration of conventional doses of teniposide. Anorexia, vomiting and diarrhoea are generally of mild severity after administration of conventional doses of topoisomerase II inhibitors. Clinical pharmacokinetic studies have revealed substantial interindividual variabilities regarding the area under the concentration-time curve values and steady-state concentrations for all drugs reviewed in this article. Irinotecan, etoposide and teniposide are degraded via complex metabolic pathways. In contrast, topotecan primarily undergoes renal excretion. Regarding etoposide and teniposide, the extent of catechol formation over time during drug metabolism may be associated with a higher risk for secondary malignancies.
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Affiliation(s)
- Jörg T Hartmann
- Department of Oncology/Hematology/Immunology/Pneumology/Rheumatology, Eberhard Karls University Tübingen, UKT - Medical Center II, Tübingen, Germany.
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Lee E, Lim SJ. The association of increased lung resistance protein expression with acquired etoposide resistance in human H460 lung cancer cell lines. Arch Pharm Res 2006; 29:1018-23. [PMID: 17146971 DOI: 10.1007/bf02969286] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Chemoresistance remains the major obstacle to successful therapy of cancer. In order to understand the mechanism of multidrug resistance (MDR) that is frequently observed in lung cancer patients, here we studied the contribution of MDR-related proteins by establishing lung cancer cell lines with acquired resistance against etoposide. We found that human H460 lung cancer cells responded to etoposide more sensitively than A549 cells. Among MDR-related proteins, the expression of p-glycoprotein (Pgp) and lung resistance protein (LRP) were much higher in A549 cells compared with that in H460 cells. When we established H460-R1 and -R2 cell lines by progressive exposure of H460 cells to increasing doses of etoposide, the response against etoposide as well as doxorubicin was greatly reduced in R1 and R2 cells, suggesting MDR induction. Induction of MDR was not accompanied by a decrease in the intracellular accumulation of etoposide and the expression of MDR-related proteins that function as drug efflux pumps such as Pgp and MRP1 was not changed. We found that the acquired resistance paralleled an increased expression of LRP in H460 cells. Taken together, our data suggest the implicative role of LRP in mediating MDR in lung cancer.
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Affiliation(s)
- Eunmyong Lee
- Department of Bioscience and Biotechnology, Sejong University, Seoul, Korea
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Tchambaz L, Schlatter C, Jakob M, Krähenbühl A, Wolf P, Krähenbühl S. Dose adaptation of antineoplastic drugs in patients with liver disease. Drug Saf 2006; 29:509-22. [PMID: 16752933 DOI: 10.2165/00002018-200629060-00004] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Dose adaptation for liver disease is important in patients treated with antineoplastic drugs because of the high prevalence of impaired liver function in this population and the dose-dependent, frequently serious adverse effects of these drugs. We classified the antineoplastic drugs marketed in Switzerland at the end of 2004 according to their bioavailability and/or hepatic extraction to predict their kinetic behaviour in patients with decreased liver function. This prediction was compared with kinetic studies carried out with these drugs in patients with liver disease. The studies were identified by a structured, computer-based literature search. Of the 69 drugs identified, 52 had a predominant extrarenal (in most cases hepatic) metabolism and/or excretion. For 49 drugs, hepatic extraction could be calculated and/or bioavailability data were available, allowing classification according to hepatic extraction. For 18 drugs, kinetic studies have been reported in patients with impaired liver function, with the findings generally resulting in quantitative recommendations for adaptation of the dosage. In particular, recommendations are precise for 16 drugs excreted by the bile (e.g. doxorubicin and derivatives and vinca alkaloids). Validation studies comparing such recommendations with kinetics and/or dynamics of antineoplastic drugs in patients with decreased liver function have not been published. We conclude that there are currently not enough data for safe use of cyctostatics in patients with liver disease. Pharmaceutical companies should be urged to provide kinetic data (especially hepatic extraction data) for the classification of such drugs and to conduct kinetic studies for drugs with primarily hepatic metabolism in patients with impaired liver function to allow quantitative advice to be given for dose adaptation.
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Affiliation(s)
- Lydia Tchambaz
- Division of Clinical Pharmacology & Toxicology, University Hopsital, Basel, Switzerland
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Abstract
An integrated approach is needed to manage cancer using the growing body of knowledge gained through scientific developments. Thousands of herbal and traditional compounds are being screened worldwide to validate their use as anti-cancerous drugs. The science of Ayurveda is supposed to add a step on to the curative aspects of cancers that have resemblance with clinical entities of arbuda and granthi mentioned in Sushrutha samhita. Hence, an attempt is made in this review to discuss about the pathology and therapeutic management of various cancers described in Ayurveda. Review of literature on anticancer drugs of plant origin revealed identification of newer ayurvedic drugs that are not mentioned in the ancient texts. These new findings add up to ayurvedic science that has been developed through ages. In addition, details of experimental and clinical studies conducted on single and compound ayurvedic preparations for their anticancer efficacy strongly emphasize ayurvedic therapy as a scientifically driven one and not simply unconventional.
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Affiliation(s)
- Premalatha Balachandran
- National Center for Natural Products Research, Department of Pharmacognosy, University of Mississippi, MS 38677, USA.
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Martincic D, Hande KR. Topoisomerase II inhibitors. CANCER CHEMOTHERAPY AND BIOLOGICAL RESPONSE MODIFIERS 2005; 22:101-21. [PMID: 16110609 DOI: 10.1016/s0921-4410(04)22005-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Danko Martincic
- Vanderbilt/Ingram Cancer Center, Vanderbilt University, Nashville, TN 37232, USA
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Kang YH, Lee E, Youk HJ, Kim SH, Lee HJ, Park YG, Lim SJ. Potentiation by alpha-tocopheryl succinate of the etoposide response in multidrug resistance protein 1-expressing glioblastoma cells. Cancer Lett 2005; 217:181-90. [PMID: 15617835 DOI: 10.1016/j.canlet.2004.07.016] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2004] [Revised: 07/14/2004] [Accepted: 07/18/2004] [Indexed: 11/19/2022]
Abstract
Multidrug resistance protein 1 (MRP1) is one of the representative members of the ATP-binding cassette superfamily of transporters that is involved in resistance to chemotherapeutic agents in cancer patients. MRP1 functions as an efflux pump of drugs, primarily those conjugated to glutathione (GSH). Decreases in the intracellular concentration of GSH have been shown to enhance the response of MRP1-overexpressing cells to MRP1-substrate drugs by limiting the available drug-GSH conjugates. We report here that alpha-tocopheryl succinate (TOS), a vitamin E analogue, decreased intracellular GSH concentration and blocked MRP1 function in glioblastoma cells. Functional blockade by TOS of MRP1 was confirmed by the enhanced accumulation of etoposide (VP-16), an MRP1-substrate drug. As a result, co-treatment of TOS with VP-16 or treatment with liposomes containing both TOS and VP-16 greatly enhanced the response of MRP1-expressing glioblastoma cells to VP-16. TOS may be a promising adjuvant for enhancing the therapeutic efficacy of VP-16 in patients with MRP1-expressing glioblastomas.
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Affiliation(s)
- Young-Hwa Kang
- Research Institute, National Cancer Center, 809 Madu-Dong, Ilsan-gu, Goyang, Gyeonggi 411-769, South Korea
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22
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John V, Mashru S, Lichtman S. Pharmacological factors influencing anticancer drug selection in the elderly. Drugs Aging 2004; 20:737-59. [PMID: 12875610 DOI: 10.2165/00002512-200320100-00003] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Persons over the age of 65 years are the fastest growing segment of the US population. In the next 30 years this segment will represent more than 20% of the population. Fifty percent of all cancers occur in this age group and therefore the total cancer burden is expected to rise. Data are becoming available that will better guide the use of chemotherapy in the older patient population. Studies are presented discussing pharmacokinetic data on a number of chemotherapeutic agents with an emphasis on those that have entered clinical practice over the past few years. Many of these agents seem to have a beneficial therapeutic index, particularly in regard to older patients. Aging can affect the pharmacokinetics of chemotherapy in a number of ways. Absorption is only modified minimally by age. The greater concern with the use of oral drugs is patient compliance. Volume of distribution is affected by changes in body composition, anaemia and decreased plasma albumin concentration. There are many drugs in which renal excretion plays an important role. Decline in glomerular filtration is a consistent phenomenon with aging. Drug metabolism is primarily affected by changes in the P450 system and coadministration of drugs which also interact with this important enzyme system. The selection of chemotherapy in the elderly is frequently determined by degree of comorbidity and the patients' functional status. These factors are critical and can often determine response and toxicity. This article discusses the changes that occur with antimetabolites, camptothecins, anthracyclines, taxanes, platinum compounds, epipodophyllotoxins and vinca alkaloids. There has also been an increasing trend toward the use of oral chemotherapy. Factors that must be considered in selecting chemotherapeutic agents include limitations of saturability of absorption, patient compliance and the pharmacokinetic and pharmacodynamic changes that occur in older patients. Interpatient variability and age-related changes in drug metabolism are discussed. Careful attention to the physiological changes with age and dose adjustments necessary for end-organ dysfunction (renal, hepatic) are needed to ensure the safe administration of chemotherapy. In this article specific diseases are discussed (breast, colon, ovarian and non-small lung cancers) with recommendations for drug selection in adjuvant chemotherapy and the treatment of metastatic disease. Future studies will need to incorporate these various factors to properly evaluate chemotherapy in older patients. Research and educational initiatives targeted to this population will need to be a priority.
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Affiliation(s)
- Veena John
- Don Monti Division of Medical Oncology, North Shore University Hospital, NYU School of Medicine, Manhasset, New York, USA
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23
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Toffoli G, Corona G, Basso B, Boiocchi M. Pharmacokinetic Optimisation of Treatment with Oral Etoposide. Clin Pharmacokinet 2004; 43:441-66. [PMID: 15139794 DOI: 10.2165/00003088-200443070-00002] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Etoposide is a derivative of podophyllotoxin widely used in the treatment of several neoplasms, including small cell lung cancer, germ cell tumours and non-Hodgkin's lymphomas. Prolonged administration of etoposide aims for continuous inhibition of topoisomerase II, the intracellular target of etoposide, thus preventing tumour cells from repairing DNA breaks. However, the clinical advantages of extended schedules as compared with conventional short-term infusions remain unclear. Oral administration of etoposide represents the most feasible and economic strategy to maintain effective concentrations of drug for extended times. Nevertheless, the efficacy of oral etoposide therapy is contingent on circumventing pharmacokinetic limitations, mainly low and variable bioavailability. Inhibition of small bowel and hepatic metabolism of etoposide with specific cytochrome P450 inhibitors or inhibition of the intestinal P-glycoprotein efflux pump have been attempted to increase the bioavailability of oral etoposide, but the best results were obtained with daily oral administration of low etoposide doses (50-100 mg/day for 14-21 days). Saturable absorption of etoposide was reported for doses greater than 200 mg/day, whereas lower doses were associated with increased bioavailability, although they were characterised by high inter- and intrapatient variability. Pharmacokinetic parameters such as plasma trough concentration between two oral administrations (C(24,trough)), drug exposure time above a threshold value and area under the plasma concentration-time curve have been correlated with the pharmacodynamic effect of oral etoposide. Pharmacokinetic-pharmacodynamic relationships indicate that severe toxicity is avoided when peak plasma concentrations do not exceed 3-5 mg/L and C(24,trough) is under the threshold limit of 0.3 mg/L. To maintain effective etoposide plasma concentrations during prolonged oral administration, pharmacokinetic variability must be monitored in each patient, taking account of factors from many pharmacokinetic studies of etoposide, including absorption, distribution, protein binding, metabolism and elimination. Dosage reduction is generally useful to avoid haematological toxicity in patients with renal dysfunction (creatinine clearance <50 mL/min). The need for dosage adjustment based on liver function in patients with liver dysfunction is not completely defined, but generally is not indicated in patients with minor liver dysfunction. Adaptive dosage adjustment based on individual pharmacokinetic parameters, estimated using limited sampling strategies and population pharmacokinetic models, is more appropriate. This approach has been used with success in different clinical trials to increase the etoposide dosage, without significantly increasing toxicity. Various pharmacodynamic models have been proposed to guide etoposide oral dosage. However, they lack precision and accuracy and need to be refined by considering other predictor variables in order to extend their application in current clinical practice.
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Affiliation(s)
- Giuseppe Toffoli
- Experimental and Clinical Pharmacology Unit, Centro di Riferimento Oncologico, National Cancer Institute, Aviano, Italy.
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24
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Lichtman SM, Skirvin JA, Vemulapalli S. Pharmacology of antineoplastic agents in older cancer patients. Crit Rev Oncol Hematol 2003; 46:101-14. [PMID: 12711355 DOI: 10.1016/s1040-8428(02)00120-8] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Persons over the age of 65 years are the fastest growing segment of the United States population. In the next 30 years it will comprise over 20% of the population. Fifty percent of all cancers occur in this age group and therefore there will be an expected rise in the total cancer burden. Data is becoming available which will better guide the use of chemotherapy in the older patient population. Studies will be presented discussing pharmacokinetic data on a number of chemotherapeutic agents with an emphasis on those which have entered practice over the past few years. Many of these agents seem to have a beneficial therapeutic index, particularly in regard to older patients. There has also been an increasing trend toward the use of oral chemotherapy. Factors that must be considered in choosing chemotherapy include limitations of saturability of absorption, patient compliance and the pharmacokinetic and pharmacodynamic changes which occur in older patients. Interpatient variability and age related changes in drug metabolism are discussed. Careful attention to the physiologic changes with age, and dose adjustments necessary for end organ dysfunction (renal, hepatic) are needed to ensure the safe administration of chemotherapy.
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Affiliation(s)
- Stuart M Lichtman
- Department of Medicine, Don Monti Division of Medical Oncology, North Shore University Hospital, New York University School of Medicine, 300 Community Drive, Manhasset, NY 11030, USA.
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25
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Hande KR. Topoisomerase II inhibitors. CANCER CHEMOTHERAPY AND BIOLOGICAL RESPONSE MODIFIERS ANNUAL 2003; 21:103-25. [PMID: 15338742 DOI: 10.1016/s0921-4410(03)21005-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Kenneth R Hande
- Vanderbilt/Ingram Cancer Center, Vanderbilt University, Nashville, TN 37232, USA.
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26
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Ciccolini J, Monjanel-Mouterde S, Bun SS, Blanc C, Duffaud F, Favre R, Durand A. Population pharmacokinetics of etoposide: application to therapeutic drug monitoring. Ther Drug Monit 2002; 24:709-14. [PMID: 12451286 DOI: 10.1097/00007691-200212000-00005] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Antineoplastic agent etoposide (VP16) displays narrow therapeutic index and erratic pharmacokinetics, and dose individualization is a convenient way for overcoming the interpatient variability, so as to maintain the drug exposure within a therapeutic range. The authors proposed a population-based Bayesian methodology to adjust routinely VP16 dosage when given as a 5-day infusion. The mean VP16 pharmacokinetic parameters of the reference population calculated from 14 patients following the two-stage method were CL = 1.92 +/- 0.512 L/h and t(1/2) = 6.7 +/- 2 hours. The reference population was next used prospectively for Bayesian dose individualization for 25 patients (47 courses) undergoing 5-day infusions of VP16. Resulting steady-state concentrations proved to be successfully adjusted to the target values in 77% of the courses. Therefore, the method presented here meets the requirements for routine therapeutic drug monitoring of VP16, a major anticancer drug extensively used in clinical oncology.
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Affiliation(s)
- Joseph Ciccolini
- Fédération de Pharmacologie Médicale et Clinique et de Pharmacocinétique, Marseille, France.
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27
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&NA;. Oral chemotherapy in the elderly: consideration of pharmacokinetics can optimise outcomes. DRUGS & THERAPY PERSPECTIVES 2002. [DOI: 10.2165/00042310-200218110-00007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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28
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Skirvin JA, Lichtman SM. Pharmacokinetic considerations of oral chemotherapy in elderly patients with cancer. Drugs Aging 2002; 19:25-42. [PMID: 11929325 DOI: 10.2165/00002512-200219010-00003] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Persons over the age of 65 years are the fastest growing segment of the US population. In the next 30 years they will comprise over 20% of the population. Fifty per cent of all cancers occur in this age group and therefore there will be an expected rise in the total cancer burden. There has been an increasing trend over the past 20 years toward the use of oral chemotherapy. This change has been encouraged by the need to decrease the costs of chemotherapy administration, patient preferences and quality of life issues. Factors that must be considered with oral chemotherapy administration include limitations of saturability of absorption, patient compliance and pharmacokinetic/pharmacodynamic changes which occur in elderly patients. Interpatient variability and drug metabolism, particularly age-related changes in drug metabolism are being studied. The cytochrome P450 system has been intensively studied because of its importance with regard to chemotherapeutic drugs. This article reviews these issues and provides details regarding specific drugs including temozolomide, thalidomide, topotecan, the fluoropyrimidines, etoposide, hydroxycarbamide (hydroxyurea), tamoxifen, and alkylating drugs. Complementary and alternative therapies are also discussed.
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Affiliation(s)
- J Andrew Skirvin
- College of Pharmacy and Allied Health Professions, St. Johns University, Jamaica, New York, USA
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29
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Toffoli G, Corona G, Sorio R, Robieux I, Basso B, Colussi AM, Boiocchi M. Population pharmacokinetics and pharmacodynamics of oral etoposide. Br J Clin Pharmacol 2001; 52:511-9. [PMID: 11736859 PMCID: PMC2014597 DOI: 10.1046/j.0306-5251.2001.01468.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
AIMS To study the population pharmacokinetics and pharmacodynamics of oral etoposide in patients with solid tumours. METHODS A prospective, open label, cross-over, bioavailability study was performed in 50 adult patients with miscellaneous, advanced stage solid tumours, who were receiving oral (100 mg capsules) etoposide for 14 days and i.v. (50 mg) etoposide on day 1 or day 7 in randomised order during the first cycle treatment. Total and unbound etoposide concentration were assayed by h.p.l.c. Population PK parameters estimation was done by using the P-Pharm software (Simed). Haematological toxicity and tumour response were the main pharmacodynamic endpoints. RESULTS Mean clearance was 1.14 l h(-1) (CV 25%). Creatinine clearance was the only covariable to significantly reduce clearance variability (residual CV 18%). (CL = 0.74 + 0.0057 CLCR; r(2) = 0.32). Mean bioavailability was 45% (CV 22%) and mean protein binding 91.5% (CV 5%). Exposure to free, pharmacologically active etoposide (free AUC p.o.) was highly variable (mean value 2.8 mg l(-1) h; CV 64%; range 0.4-9.5). It decreased with increased creatinine clearance and increased with age which accounted for 9% of the CV. Mean free AUC p.o. was the best predictor of neutropenia. Free AUC50 (exposure producing a 50% reduction in absolute neutrophil count) was 1.80 mg l(-1) h. In patients with lung cancer, the free AUC p.o. was higher in the two patients with responsive tumour (5.9 mg l(-1) h) than in patients with stable (2.1 mg l-1 h) or progressive disease (2.3 mg l-1 h) (P = 0.01). CONCLUSIONS Exposure to free etoposide during prolonged oral treatment is highly variable and is the main determinant of pharmacodynamic effects. The population PK model based on creatinine clearance is poorly predictive of exposure. Therapeutic drug monitoring would be necessary for dose individualization or to study the relationship between exposure and antitumour effect.
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Affiliation(s)
- Giuseppe Toffoli
- Division of Experimental Oncology 1, Pharmacology Group, Centro di Riferimento Oncologico, National Cancer CenterAviano, Italy
| | - Giuseppe Corona
- Division of Experimental Oncology 1, Pharmacology Group, Centro di Riferimento Oncologico, National Cancer CenterAviano, Italy
| | - Roberto Sorio
- Division of Medical Oncology, Centro di Riferimento Oncologico, National Cancer CenterAviano, Italy
| | - Isabelle Robieux
- Division of Medical Oncology, Centro di Riferimento Oncologico, National Cancer CenterAviano, Italy
| | - Barbara Basso
- Division of Experimental Oncology 1, Pharmacology Group, Centro di Riferimento Oncologico, National Cancer CenterAviano, Italy
| | - Anna Maria Colussi
- Division of Medical Oncology, Centro di Riferimento Oncologico, National Cancer CenterAviano, Italy
| | - Mauro Boiocchi
- Division of Experimental Oncology 1, Pharmacology Group, Centro di Riferimento Oncologico, National Cancer CenterAviano, Italy
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30
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Chen CL, Rawwas J, Sorrell A, Eddy L, Uckun FM. Bioavailability and pharmacokinetic features of etoposide in childhood acute lymphoblastic leukemia patients. Leuk Lymphoma 2001; 42:317-27. [PMID: 11699396 DOI: 10.3109/10428190109064588] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The bioavailability and pharmacokinetic characteristics of etoposide were studied in 12 relapsed B-lineage acute lymphoblastic leukemia (ALL) patients after both intravenous (i.v.) infusion and oral administration. Following a 1 hour i.v. infusion of 50 mg/m2 etoposide, the elimination half-life ranged from 49.8 min to 509.4 min (mean +/- SD = 218.6 +/- 134.7 min), the MRT ranged from 71.8 to 734.9 min (mean +/- SD = 315.4 +/- 194.3 min) and the systemic clearance of etoposide ranged from 15.7 to 38.0 ml/min/m2 (mean +/- SD = 24.1 +/- 7.0 ml/min/m2). The AUC ranged from 2234.9 to 5427.0 microM.min) (mean +/- SD = 3827.8 +/- 1069.5 microM.min) and Vc ranged from 2026.9 to 13,505.2 ml/m2 (mean +/- SD = 6825.4 +/- 3278.5 ml/m2). The maximum plasma etoposide levels ranged from 6.0 to 28.4 microM (mean +/- SD = 13.6 +/- 6.3 microM). The bioavailability of oral etoposide was determined by comparing the AUC following i.v. infusion to the AUC following oral administration in the same patient. The overall bioavailability (mean +/- SD) was 60.6 +/- 22.4% (ranged from 17.6% to 91.2%). The elimination half-life following oral administration (mean +/- SD) was 209.8 +/- 196.3 min (ranged from 51.0 to 794.2 min). The time required to reach the maximum plasma etoposide concentration was 145.4 +/- 118.7 min (ranged from 23.7 to 396.9 min). To our knowledge, this is the first report concerning the bioavailability of etoposide in pediatric leukemia patients. All of the other pharmacokinetic properties of etoposide in pediatric B-lineage ALL leukemia patients reported here were similar to those described previously.
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Affiliation(s)
- C L Chen
- Parker Hughes Cancer Center, Department of Pharmaceutical Sciences, 2665 Long Lake Road, St. Paul, MN 55113, USA
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