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Picard LC, Rich FJ, Kenwright DN, Stevens AJ. Epigenetic changes associated with Bacillus Calmette-Guerin (BCG) treatment in bladder cancer. Biochim Biophys Acta Rev Cancer 2024; 1879:189123. [PMID: 38806074 DOI: 10.1016/j.bbcan.2024.189123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Revised: 05/20/2024] [Accepted: 05/24/2024] [Indexed: 05/30/2024]
Abstract
Bacillus Calmette-Guérin (BCG) treatment for non-muscle invasive bladder cancer (NMIBC) is an established immunotherapeutic, however, a significant portion of patients do not respond to treatment. Despite extensive research into the therapeutic mechanism of BCG, gaps remain in our understanding. This review specifically focuses on the epigenomic contributions in the immune microenvironment, in the context of BCG treatment for NMIBC. We also summarise the current understanding of NMIBC epigenetic characteristics, and discuss how future targeted strategies for BCG therapy should incorporate epigenomic biomarkers in conjunction with genomic biomarkers.
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Affiliation(s)
- Lucy C Picard
- University of Otago, Wellington, Department of Pathology and Molecular Medicine, Wellington 6021, New Zealand
| | - Fenella J Rich
- University of Otago, Wellington, Department of Pathology and Molecular Medicine, Wellington 6021, New Zealand
| | - Diane N Kenwright
- University of Otago, Wellington, Department of Pathology and Molecular Medicine, Wellington 6021, New Zealand
| | - Aaron J Stevens
- University of Otago, Wellington, Department of Pathology and Molecular Medicine, Wellington 6021, New Zealand.
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2
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El-Serafi I, Steele S. Cyclophosphamide Pharmacogenomic Variation in Cancer Treatment and Its Effect on Bioactivation and Pharmacokinetics. Adv Pharmacol Pharm Sci 2024; 2024:4862706. [PMID: 38966316 PMCID: PMC11223907 DOI: 10.1155/2024/4862706] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2023] [Revised: 06/06/2024] [Accepted: 06/11/2024] [Indexed: 07/06/2024] Open
Abstract
Cyclophosphamide (Cy) is a prodrug that is mainly bioactivated by cytochrome P450 (CYP) 2B6 enzyme. Several other enzymes are also involved in its bioactivation and affect its kinetics. Previous studies have shown the effect of the enzymes' genetic polymorphisms on Cy kinetics and its clinical outcome. These results were controversial primarily because of the involvement of several interacting enzymes in the Cy metabolic pathway, which can also be affected by several clinical factors as well as other drug interactions. In this review article, we present the effect of CYP2B6 polymorphisms on Cy kinetics since it is the main bioactivating enzyme, as well as discussing all previously reported enzymes and clinical factors that can alter Cy efficacy. Additionally, we present explanations for key Cy side effects related to the nature and site of its bioactivation. Finally, we discuss the role of busulphan in conditioning regimens in the Cy metabolic pathway as a clinical example of drug-drug interactions involving several enzymes. By the end of this article, our aim is to have provided a comprehensive summary of Cy pharmacogenomics and the effect on its kinetics. The utility of these findings in the development of new strategies for Cy personalized patient dose adjustment will aid in the future optimization of patient specific Cy dosages and ultimately in improving clinical outcomes. In conclusion, CYP2B6 and several other enzyme polymorphisms can alter Cy kinetics and consequently the clinical outcomes. However, the precise quantification of Cy kinetics in any individual patient is complex as it is clearly under multifactorial genetic control. Additionally, other clinical factors such as the patient's age, diagnosis, concomitant medications, and clinical status should also be considered.
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Affiliation(s)
- Ibrahim El-Serafi
- Basic Medical Sciences DepartmentCollege of MedicineAjman University, Ajman, UAE
- Department of Hand Surgery, and Plastic Surgery and BurnsLinköping University Hospital, Linkoöping, Sweden
| | - Sinclair Steele
- Pathological Sciences DepartmentCollege of MedicineAjman University, Ajman, UAE
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3
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Salazar YEAR, Louzada J, Puça MCSDB, Guimarães LFF, Vieira JLF, de Siqueira AM, Gil JP, de Brito CFA, de Sousa TN. Delayed gametocyte clearance in Plasmodium vivax malaria is associated with polymorphisms in the cytochrome P450 reductase (CPR). Antimicrob Agents Chemother 2024; 68:e0120423. [PMID: 38411047 PMCID: PMC10989009 DOI: 10.1128/aac.01204-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Accepted: 01/31/2024] [Indexed: 02/28/2024] Open
Abstract
Primaquine (PQ) is the main drug used to eliminate dormant liver stages and prevent relapses in Plasmodium vivax malaria. It also has an effect on the gametocytes of Plasmodium falciparum; however, it is unclear to what extent PQ affects P. vivax gametocytes. PQ metabolism involves multiple enzymes, including the highly polymorphic CYP2D6 and the cytochrome P450 reductase (CPR). Since genetic variability can impact drug metabolism, we conducted an evaluation of the effect of CYP2D6 and CPR variants on PQ gametocytocidal activity in 100 subjects with P. vivax malaria. To determine gametocyte density, we measured the levels of pvs25 transcripts in samples taken before treatment (D0) and 72 hours after treatment (D3). Generalized estimating equations (GEEs) were used to examine the effects of enzyme variants on gametocyte densities, adjusting for potential confounding factors. Linear regression models were adjusted to explore the predictors of PQ blood levels measured on D3. Individuals with the CPR mutation showed a smaller decrease in gametocyte transcript levels on D3 compared to those without the mutation (P = 0.02, by GEE). Consistent with this, higher PQ blood levels on D3 were associated with a lower reduction in pvs25 transcripts. Based on our findings, the CPR variant plays a role in the persistence of gametocyte density in P. vivax malaria. Conceptually, our work points to pharmacogenetics as a non-negligible factor to define potential host reservoirs with the propensity to contribute to transmission in the first days of CQ-PQ treatment, particularly in settings and seasons of high Anopheles human-biting rates.
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Affiliation(s)
- Yanka Evellyn Alves Rodrigues Salazar
- Molecular Biology and Malaria Immunology Research Group, Instituto René Rachou, Fundação Oswaldo Cruz (FIOCRUZ), Belo Horizonte, Minas Gerais, Brazil
| | - Jaime Louzada
- Universidade Federal de Roraima, Boa Vista, Roraima, Brazil
| | - Maria Carolina Silva de Barros Puça
- Molecular Biology and Malaria Immunology Research Group, Instituto René Rachou, Fundação Oswaldo Cruz (FIOCRUZ), Belo Horizonte, Minas Gerais, Brazil
| | - Luiz Felipe Ferreira Guimarães
- Molecular Biology and Malaria Immunology Research Group, Instituto René Rachou, Fundação Oswaldo Cruz (FIOCRUZ), Belo Horizonte, Minas Gerais, Brazil
| | | | - André Machado de Siqueira
- Instituto Nacional de Infectologia Evandro Chagas, Fundação Oswaldo Cruz (FIOCRUZ), Rio de Janeiro, Rio de Janeiro, Brazil
| | - José Pedro Gil
- Department of Microbiology, Tumor and Cell biology, Karolinska Institutet, Solna, Sweden
| | - Cristiana Ferreira Alves de Brito
- Molecular Biology and Malaria Immunology Research Group, Instituto René Rachou, Fundação Oswaldo Cruz (FIOCRUZ), Belo Horizonte, Minas Gerais, Brazil
| | - Tais Nobrega de Sousa
- Molecular Biology and Malaria Immunology Research Group, Instituto René Rachou, Fundação Oswaldo Cruz (FIOCRUZ), Belo Horizonte, Minas Gerais, Brazil
- Department of Microbiology, Tumor and Cell biology, Karolinska Institutet, Solna, Sweden
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4
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Fang Y, Yang H, Hu G, Lu J, Zhou J, Gao N, Gu Y, Zhang C, Qiu J, Guo Y, Zhang Y, Wen Q, Qiao H. The POR rs10954732 polymorphism decreases susceptibility to hepatocellular carcinoma and hepsin as a prognostic biomarker correlated with immune infiltration based on proteomics. J Transl Med 2022; 20:88. [PMID: 35164791 PMCID: PMC8842912 DOI: 10.1186/s12967-022-03282-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Accepted: 01/25/2022] [Indexed: 11/10/2022] Open
Abstract
The effect of the cytochrome P450 oxidoreductase (POR) rs10954732 (G > A) polymorphism on hepatocellular carcinoma (HCC) susceptibility is unknown. Here we found that A allele carriers showed a 69% decrease in susceptibility to HCC with overall survival (OS) prolonged to 199%, accompanied by lower activity for cytochrome P450 2E1. A total of 222 differentially expressed proteins were mainly enriched in neutrophil and T cell activation and involved in the immune and inflammatory responses, constituting the altered immune tumor microenvironment related with A allele by proteomics analysis. Hepsin (HPN) showed significant down-regulation in HCC and up-regulation in A allele carriers. A lower HPN level was associated with increased susceptibility to HCC and a worse prognosis. Moreover, HPN is a potential independent prognostic biomarker for HCC and is strongly associated with clinicopathological features, tumor-infiltrating status of immune cells both in our discovery cohort and database surveys. Our findings provide a new potential mechanism by which HPN may play an important role in the susceptibility of rs10954732 A allele carriers to HCC and their prognosis through tumor immune infiltration, thus offering potential insights for future studies on tumor immunotherapy.
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Belitskiy GA, Kirsanov KI, Lesovaya EA, Yakubovskaya MG. Drug-Related Carcinogenesis: Risk Factors and Approaches for Its Prevention. BIOCHEMISTRY (MOSCOW) 2020; 85:S79-S107. [PMID: 32087055 DOI: 10.1134/s0006297920140059] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
The review summarizes the data on the role of metabolic and repair systems in the mechanisms of therapy-related carcinogenesis and the effect of their polymorphism on the cancer development risk. The carcinogenic activity of different types of drugs, from the anticancer agents to analgesics, antipyretics, immunomodulators, hormones, natural remedies, and non-cancer drugs, is described. Possible approaches for the prevention of drug-related cancer induction at the initiation and promotion stages are discussed.
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Affiliation(s)
- G A Belitskiy
- Blokhin Russian Cancer Research Center, Ministry of Health of Russian Federation, Moscow, 115478, Russia
| | - K I Kirsanov
- Blokhin Russian Cancer Research Center, Ministry of Health of Russian Federation, Moscow, 115478, Russia. .,Peoples' Friendship University of Russia, Moscow, 117198, Russia
| | - E A Lesovaya
- Blokhin Russian Cancer Research Center, Ministry of Health of Russian Federation, Moscow, 115478, Russia.,Pavlov Ryazan State Medical University, Ryazan, 390026, Russia
| | - M G Yakubovskaya
- Blokhin Russian Cancer Research Center, Ministry of Health of Russian Federation, Moscow, 115478, Russia
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Mona A.M. Abo-Zeid, Farghaly AA, Hassan EM, Abdel-Samie NS. Phenolic Compounds of Codiaeum variegatum Spirale Lessened Cytotoxic and Genotoxic Effects of Mitomycin C in Mice Somatic and Germ Cells. CYTOL GENET+ 2020. [DOI: 10.3103/s0095452719060057] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Polymorphisms in cytochrome P450 oxidoreductase and its effect on drug metabolism and efficacy. Pharmacogenet Genomics 2017; 27:337-346. [DOI: 10.1097/fpc.0000000000000297] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Hu L, Lv JF, Zhuo W, Zhang CM, Zhou HH, Fan L. Effect of NADPH-cytochrome P450 reductase on all-trans-retinoic acid efficacy and cytochrome P450 26A1 expression in human myeloid leukaemia HL-60 cells. ACTA ACUST UNITED AC 2016; 68:1193-202. [PMID: 27366899 DOI: 10.1111/jphp.12591] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Accepted: 05/29/2016] [Indexed: 11/29/2022]
Abstract
OBJECTIVES All-trans-retinoic acid (ATRA), a naturally occurring metabolite of vitamin A, has been shown to have great potential as an antitumorigenic drug to treat acute leukaemia by promoting cancer cell differentiation. Cytochrome P450 oxidoreductase (POR) is the only obligate electron donor for all of the microsomal cytochrome P450 enzymes including CYP26A1 which is highly specific for ATRA metabolism and efficacy in human myeloid leukaemia cells. In this study, we aimed to investigate the effect of POR on ATRA efficacy and CYP26A1 expression in human myeloid leukaemia HL-60 cells. METHODS Stably expressed POR and POR-RNAi HL-60 cell lines were established by transfecting POR overexpression or RNAi (RNA interference) vectors mediated by lentivirus. The protein expression of POR and CYP26A1 was examined by Western blot. The potential roles of POR on ATRA efficacy in HL-60 cells were explored by cell viability assay, cell cycle distribution, cellular differentiation and apoptosis analysis. KEY FINDINGS All-trans-retinoic acid treatment caused the expression of POR upregulation and CYP26A1 downregulation in dose- and time-dependent manners. POR overexpression decreased CYP26A1 expression in HL-60 cells. When POR gene was interfered, the downregulation of CYP26A1 expression by ATRA was abolished. In addition, POR overexpression in HL-60 cells significantly compromised ATRA-induced cell proliferation inhibition, cell cycle arrest, differentiation and apoptosis, whereas downregulation of POR significantly potentiated ATRA effects. CONCLUSIONS Our study therefore suggested that POR played an important role in regulating ATRA efficacy and CYP26A1 expression in HL-60 cells.
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Affiliation(s)
- Lei Hu
- Department of Clinical Pharmacology, Xiangya Hospital, Central South University, Changsha, China.,Institute of Clinical Pharmacology, Hunan Key Laboratory of Pharmacogenetics, Central South University, Changsha, China
| | - Jin-Feng Lv
- Department of Clinical Pharmacology, Xiangya Hospital, Central South University, Changsha, China.,Institute of Clinical Pharmacology, Hunan Key Laboratory of Pharmacogenetics, Central South University, Changsha, China.,Department of Pharmacy, Xiangya Hospital, Central South University, Changsha, China.,Institute of Hospital Pharmacy, Central South University, Changsha, China
| | - Wei Zhuo
- Department of Clinical Pharmacology, Xiangya Hospital, Central South University, Changsha, China.,Institute of Clinical Pharmacology, Hunan Key Laboratory of Pharmacogenetics, Central South University, Changsha, China
| | - Cong-Min Zhang
- Department of Clinical Pharmacology, Xiangya Hospital, Central South University, Changsha, China.,Institute of Clinical Pharmacology, Hunan Key Laboratory of Pharmacogenetics, Central South University, Changsha, China
| | - Hong-Hao Zhou
- Department of Clinical Pharmacology, Xiangya Hospital, Central South University, Changsha, China.,Institute of Clinical Pharmacology, Hunan Key Laboratory of Pharmacogenetics, Central South University, Changsha, China
| | - Lan Fan
- Department of Clinical Pharmacology, Xiangya Hospital, Central South University, Changsha, China.,Institute of Clinical Pharmacology, Hunan Key Laboratory of Pharmacogenetics, Central South University, Changsha, China
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El-Serafi I, Afsharian P, Moshfegh A, Hassan M, Terelius Y. Cytochrome P450 Oxidoreductase Influences CYP2B6 Activity in Cyclophosphamide Bioactivation. PLoS One 2015; 10:e0141979. [PMID: 26544874 PMCID: PMC4636385 DOI: 10.1371/journal.pone.0141979] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2015] [Accepted: 10/15/2015] [Indexed: 12/19/2022] Open
Abstract
Introduction Cyclophosphamide is commonly used as an important component in conditioning prior to hematopoietic stem cell transplantation, a curative treatment for several hematological diseases. Cyclophosphamide is a prodrug activated mainly by cytochrome P450 2B6 (CYP2B6) in the liver. A high degree of inter- and intra-individual variation in cyclophosphamide kinetics has been reported in several studies. Materials and Methods Hydroxylation of cyclophosphamide was investigated in vitro using three microsomal batches of CYP2B6*1 with different ratios of POR/CYP expression levels. Twenty patients undergoing hematopoietic stem cell transplantation were also included in the study. All patients received an i.v. infusion of cyclophosphamide (60 mg/kg/day, for two days) as a part of their conditioning. Blood samples were collected from each patient before cyclophosphamide infusion, 6 h after the first dose and before and 6 h after the second dose. POR gene expression was measured by mRNA analysis and the pharmacokinetics of cyclophosphamide and its active metabolite were determined. Results A strong correlation between the in vitro intrinsic clearance of cyclophosphamide and the POR/CYP ratio was found. The apparent Km for CYP2B6.1 was almost constant (3-4 mM), while the CLint values were proportional to the POR/CYP ratio (3-34 μL/min/nmol CYP). In patients, the average expression of the POR gene in blood was significantly (P <0.001) up-regulated after cyclophosphamide infusion, with high inter-individual variations and significant correlation with the concentration ratio of the active metabolite 4-hydroxy-cyclophosphamide/cyclophosphamide. Nine patients were carriers for POR*28; four patients had relatively high POR expression. Conclusions This investigation shows for the first time that POR besides CYP2B6 can influence cyclophosphamide metabolism. Our results indicate that not only CYPs are important, but also POR expression and/or activity may influence cyclophosphamide bioactivation, affecting therapeutic efficacy and treatment related toxicity and hence on clinical outcome. Thus, both POR and CYP genotype and expression levels may have to be taken into account when personalizing treatment schedules to achieve optimal therapeutic drug plasma concentrations of cyclophosphamide.
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Affiliation(s)
- Ibrahim El-Serafi
- Experimental Cancer Medicine (ECM), Department of Laboratory Medicine, Karolinska Institutet, Huddinge, Stockholm, Sweden
| | - Parvaneh Afsharian
- Experimental Cancer Medicine (ECM), Department of Laboratory Medicine, Karolinska Institutet, Huddinge, Stockholm, Sweden
| | - Ali Moshfegh
- Cancer Center of Karolinska (CCK), Department of Oncology-Pathology, Karolinska Institutet, Solna, Stockholm, Sweden
| | - Moustapha Hassan
- Experimental Cancer Medicine (ECM), Department of Laboratory Medicine, Karolinska Institutet, Huddinge, Stockholm, Sweden
- Department of Clinical Research Centre, Karolinska University Hospital-Huddinge, Stockholm, Sweden
- * E-mail:
| | - Ylva Terelius
- Department of Discovery Research, Medivir AB, Huddinge, Sweden
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Xiao X, Ma G, Li S, Wang M, Liu N, Ma L, Zhang Z, Chu H, Zhang Z, Wang SL. Functional POR A503V is associated with the risk of bladder cancer in a Chinese population. Sci Rep 2015; 5:11751. [PMID: 26123203 PMCID: PMC4485255 DOI: 10.1038/srep11751] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Accepted: 06/04/2015] [Indexed: 12/11/2022] Open
Abstract
Human cytochrome P450 oxidoreductase (POR) plays important roles in the metabolism of exogenous carcinogens and endogenous sterol hormones. However, few studies have explored the association between POR variants and the risk of bladder cancer. In this study, we first sequenced all 16 POR exons among 50 randomly selected controls, and found three variants, rs1135612, rs1057868 (A503V) and rs2228104, which were then assessed the relation to risk of bladder cancer in a case-control study of 1,050 bladder cancer cases and 1,404 cancer-free controls in a Chinese population. People with A503V TT genotype have a decreased risk of bladder cancer in a recessive model (TT vs. CC/CT, OR = 0.73, 95% CI = 0.57–0.93), which was more pronounced among elderly male, non-smoking, subjects. Especially, A503V TT genotype showed a protective effect in the invasive tumor stage. Functional analysis revealed that A503V activity decreased in cytochrome c reduction (50.5 units/mg vs. 135.4 units/mg), mitomycin C clearance (38.3% vs. 96.8%), and mitomycin C-induced colony formation (78.0 vs 34.3 colonies per dish). The results suggested that POR A503V might decrease the risk of bladder cancer by reducing its metabolic activity, and should be a potential biomarker for predicting the susceptibility to human bladder cancer.
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Affiliation(s)
- Xue Xiao
- 1] Key Lab of Modern Toxicology of Ministry of Education, School of Public Health, Nanjing Medical University, 101 Longmian Avenue Nanjing 211166, P. R. China [2] State Key Lab of Reproductive Medicine, Institute of Toxicology, Nanjing Medical University, 140 Hanzhong Rd., Nanjing 210029, P. R. China
| | - Gaoxiang Ma
- Key Lab of Modern Toxicology of Ministry of Education, School of Public Health, Nanjing Medical University, 101 Longmian Avenue Nanjing 211166, P. R. China
| | - Shushu Li
- 1] Key Lab of Modern Toxicology of Ministry of Education, School of Public Health, Nanjing Medical University, 101 Longmian Avenue Nanjing 211166, P. R. China [2] State Key Lab of Reproductive Medicine, Institute of Toxicology, Nanjing Medical University, 140 Hanzhong Rd., Nanjing 210029, P. R. China
| | - Meilin Wang
- Key Lab of Modern Toxicology of Ministry of Education, School of Public Health, Nanjing Medical University, 101 Longmian Avenue Nanjing 211166, P. R. China
| | - Nian Liu
- 1] Key Lab of Modern Toxicology of Ministry of Education, School of Public Health, Nanjing Medical University, 101 Longmian Avenue Nanjing 211166, P. R. China [2] State Key Lab of Reproductive Medicine, Institute of Toxicology, Nanjing Medical University, 140 Hanzhong Rd., Nanjing 210029, P. R. China
| | - Lan Ma
- Key Lab of Modern Toxicology of Ministry of Education, School of Public Health, Nanjing Medical University, 101 Longmian Avenue Nanjing 211166, P. R. China
| | - Zhan Zhang
- 1] Key Lab of Modern Toxicology of Ministry of Education, School of Public Health, Nanjing Medical University, 101 Longmian Avenue Nanjing 211166, P. R. China [2] State Key Lab of Reproductive Medicine, Institute of Toxicology, Nanjing Medical University, 140 Hanzhong Rd., Nanjing 210029, P. R. China
| | - Haiyan Chu
- Key Lab of Modern Toxicology of Ministry of Education, School of Public Health, Nanjing Medical University, 101 Longmian Avenue Nanjing 211166, P. R. China
| | - Zhengdong Zhang
- Key Lab of Modern Toxicology of Ministry of Education, School of Public Health, Nanjing Medical University, 101 Longmian Avenue Nanjing 211166, P. R. China
| | - Shou-Lin Wang
- 1] Key Lab of Modern Toxicology of Ministry of Education, School of Public Health, Nanjing Medical University, 101 Longmian Avenue Nanjing 211166, P. R. China [2] State Key Lab of Reproductive Medicine, Institute of Toxicology, Nanjing Medical University, 140 Hanzhong Rd., Nanjing 210029, P. R. China
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Hu CS, Wu QH, Hu DY. Cardiovascular, diabetes, and cancer strips: evidences, mechanisms, and classifications. J Thorac Dis 2014; 6:1319-28. [PMID: 25276377 DOI: 10.3978/j.issn.2072-1439.2014.07.15] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Accepted: 06/17/2014] [Indexed: 01/30/2023]
Abstract
OBJECTIVES To report and name firstly that there are cardiovascular disease (CVD), diabetes mellitus (DM) and cancers (CDC) strips; and disclose their mechanisms, classifications, and clinical significances. STUDY DESIGN Narrative and systematic review study and interpretive analysis. METHODS DATA SOURCES AND STUDY SELECTION to collect and present related evidences on CDC strips from evidence-based, open-access, both Chinese- and English-language literatures in recent 10 years on clinical trials from PubMed according to keywords "CVD, DM and cancers" as well as authors' extensive clinical experience with the treatment of more than fifty thousands of patients with CVD, diabetes and cancers over the past decades, and analyze their related mechanisms and categories which based on authors' previous works. DATA EXTRACTION data were mainly extracted from 48 articles which are listed in the reference section of this review. Qualitative, quantitative and mixed data were included, narratively and systematically reviewed. RESULTS With several conceptual and technical breakthrough, authors present related evidences on CDC strips, these are, CVD and DM, DM and cancers, cancers and CVD linked, respectively; And "Bad SEED" +/- "bad soil" theory or doctrine may explain this phenomenon due to "internal environmental injure, abnormal or unbalance" in human body resulting from the role of risk factors (RFs) related multi-pathways and multi-targets, which including organ & tissue (e.g., vascular-specific), cell and gene-based mechanisms. Their classifications include main strips/type B, and Branches/type A as showed by tables and figures in this article. CONCLUSIONS There are CDC strips and related mechanisms and classifications. CDC strips may help us to understand, prevent, and control related common non-communicable diseases (NCDs) as well as these high risk strips.
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Affiliation(s)
- Chun-Song Hu
- 1 Department of Cardiovascular Medicine, Nanchang University, Nanchang 330006, China ; 2 Cardiovascular Center, Peking University People's Hospital, Beijing 100044, China
| | - Qing-Hua Wu
- 1 Department of Cardiovascular Medicine, Nanchang University, Nanchang 330006, China ; 2 Cardiovascular Center, Peking University People's Hospital, Beijing 100044, China
| | - Da-Yi Hu
- 1 Department of Cardiovascular Medicine, Nanchang University, Nanchang 330006, China ; 2 Cardiovascular Center, Peking University People's Hospital, Beijing 100044, China
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Kandel SE, Lampe JN. Role of protein-protein interactions in cytochrome P450-mediated drug metabolism and toxicity. Chem Res Toxicol 2014; 27:1474-86. [PMID: 25133307 PMCID: PMC4164225 DOI: 10.1021/tx500203s] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
![]()
Through their unique oxidative chemistry,
cytochrome P450 monooxygenases
(CYPs) catalyze the elimination of most drugs and toxins from the
human body. Protein–protein interactions play a critical role
in this process. Historically, the study of CYP–protein interactions
has focused on their electron transfer partners and allosteric mediators,
cytochrome P450 reductase and cytochrome b5. However, CYPs can bind
other proteins that also affect CYP function. Some examples include
the progesterone receptor membrane component 1, damage resistance
protein 1, human and bovine serum albumin, and intestinal fatty acid
binding protein, in addition to other CYP isoforms. Furthermore, disruption
of these interactions can lead to altered paths of metabolism and
the production of toxic metabolites. In this review, we summarize
the available evidence for CYP protein–protein interactions
from the literature and offer a discussion of the potential impact
of future studies aimed at characterizing noncanonical protein–protein
interactions with CYP enzymes.
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Affiliation(s)
- Sylvie E Kandel
- XenoTech, LLC , 16825 West 116th Street, Lenexa, Kansas 66219, United States
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Yang S, Qiu Z, Zhang Q, Chen J, Chen X. Inhibitory Effects of Calf Thymus DNA on Metabolism Activity of CYP450 Enzyme in Human Liver Microsomes. Drug Metab Pharmacokinet 2014; 29:475-81. [DOI: 10.2133/dmpk.dmpk-13-rg-131] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Pharmacogenetics of P450 oxidoreductase: implications in drug metabolism and therapy. Pharmacogenet Genomics 2013; 22:812-9. [PMID: 23047293 DOI: 10.1097/fpc.0b013e328358d92b] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
The redox reaction of cytochrome P450 enzymes (CYP) is an important physiological and biochemical reaction in the human body, as it is involved in the oxidative metabolism of both endogenous and exogenous substrates. Cytochrome P450 oxidoreductase (POR) is the only obligate electron donor for all of the hepatic microsomal CYP enzymes. It plays a crucial role in drug metabolism and treatment by not only acting as an electron donor involved in drug metabolism mediated by CYP enzymes but also by directly inducing the transformation of some antitumor precursors. Studies have found that the gene encoding human POR is highly polymorphic, which is of considerable clinical significance as it affects the metabolism and curative effects of clinically used drugs. This review aims to discuss the effect of POR and its genetic polymorphisms on drug metabolism and therapy, as well as the potential mechanisms of POR pharmacogenetics.
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Pandey AV, Flück CE. NADPH P450 oxidoreductase: structure, function, and pathology of diseases. Pharmacol Ther 2013; 138:229-54. [PMID: 23353702 DOI: 10.1016/j.pharmthera.2013.01.010] [Citation(s) in RCA: 176] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2012] [Accepted: 12/26/2012] [Indexed: 01/18/2023]
Abstract
Cytochrome P450 oxidoreductase (POR) is an enzyme that is essential for multiple metabolic processes, chiefly among them are reactions catalyzed by cytochrome P450 proteins for metabolism of steroid hormones, drugs and xenobiotics. Mutations in POR cause a complex set of disorders that often resemble defects in steroid metabolizing enzymes 17α-hydroxylase, 21-hydroxylase and aromatase. Since our initial reports of POR mutations in 2004, more than 200 different mutations and polymorphisms in POR gene have been identified. Several missense variations in POR have been tested for their effect on activities of multiple steroid and drug metabolizing P450 proteins. Mutations in POR may have variable effects on different P450 partner proteins depending on the location of the mutation. The POR mutations that disrupt the binding of co-factors have negative impact on all partner proteins, while mutations causing subtle structural changes may lead to altered interaction with specific partner proteins and the overall effect may be different for each partner. This review summarizes the recent discoveries related to mutations and polymorphisms in POR and discusses these mutations in the context of historical developments in the discovery and characterization of POR as an electron transfer protein. The review is focused on the structural, enzymatic and clinical implications of the mutations linked to newly identified disorders in humans, now categorized as POR deficiency.
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Affiliation(s)
- Amit V Pandey
- Department of Pediatrics, Division of Pediatric Endocrinology and Diabetology, University Children's Hospital Bern, and Department of Clinical Research, University of Bern, 3004 Bern, Switzerland.
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Rodeiro I, Hernandez S, Morffi J, Herrera JA, Gómez-Lechón MJ, Delgado R, Espinosa-Aguirre JJ. Evaluation of genotoxicity and DNA protective effects of mangiferin, a glucosylxanthone isolated from Mangifera indica L. stem bark extract. Food Chem Toxicol 2012; 50:3360-6. [PMID: 22749943 DOI: 10.1016/j.fct.2012.06.032] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2012] [Revised: 06/19/2012] [Accepted: 06/20/2012] [Indexed: 11/17/2022]
Abstract
Mangiferin is a glucosylxantone isolated from Mangifera indica L. stem bark. Several studies have shown its pharmacological properties which make it a promising candidate for putative therapeutic use. This study was focused to investigate the in vitro genotoxic effects of mangiferin in the Ames test, SOS Chromotest and Comet assay. The genotoxic effects in bone marrow erythrocytes from NMRI mice orally treated with mangiferin (2000 mg/kg) were also evaluated. Additionally, its potential antimutagenic activity against several mutagens in the Ames test and its effects on CYP1A1 activity were assessed. Mangiferin (50-5000 μg/plate) did not increased the frequency of reverse mutations in the Ames test, nor induced primary DNA damage (5-1000 μg/mL) to Escherichia coli PQ37 cells under the SOS Chromotest. It was observed neither single strand breaks nor alkali-labile sites in blood peripheral lymphocytes or hepatocytes after 1h exposition to 10-500 μg/mL of mangiferin under the Comet assay. Furthermore, micronucleus studies showed mangiferin neither induced cytotoxic activity nor increased the frequency of micronucleated/binucleated cells in mice bone marrow. In short, mangiferin did not induce cytotoxic or genotoxic effects but it protect against DNA damage which would be associated with its antioxidant properties and its capacity to inhibit CYP enzymes.
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Affiliation(s)
- I Rodeiro
- Departamento de Farmacología, Centro de Bioproductos Marinos (CEBIMAR), Loma y 37, Vedado, P.O. Box 10400, La Habana, Cuba.
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Chen X, Pan LQ, Naranmandura H, Zeng S, Chen SQ. Influence of various polymorphic variants of cytochrome P450 oxidoreductase (POR) on drug metabolic activity of CYP3A4 and CYP2B6. PLoS One 2012; 7:e38495. [PMID: 22719896 PMCID: PMC3373556 DOI: 10.1371/journal.pone.0038495] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2012] [Accepted: 05/08/2012] [Indexed: 11/20/2022] Open
Abstract
Cytochrome P450 oxidoreductase (POR) is known as the sole electron donor in the metabolism of drugs by cytochrome P450 (CYP) enzymes in human. However, little is known about the effect of polymorphic variants of POR on drug metabolic activities of CYP3A4 and CYP2B6. In order to better understand the mechanism of the activity of CYPs affected by polymorphic variants of POR, six full-length mutants of POR (e.g., Y181D, A287P, K49N, A115V, S244C and G413S) were designed and then co-expressed with CYP3A4 and CYP2B6 in the baculovirus-Sf9 insect cells to determine their kinetic parameters. Surprisingly, both mutants, Y181D and A287P in POR completely inhibited the CYP3A4 activity with testosterone, while the catalytic activity of CYP2B6 with bupropion was reduced to approximately ∼70% of wild-type activity by Y181D and A287P mutations. In addition, the mutant K49N of POR increased the CLint (Vmax/Km) of CYP3A4 up to more than 31% of wild-type, while it reduced the catalytic efficiency of CYP2B6 to 74% of wild-type. Moreover, CLint values of CYP3A4-POR (A115V, G413S) were increased up to 36% and 65% of wild-type respectively. However, there were no appreciable effects observed by the remaining two mutants of POR (i.e., A115V and G413S) on activities of CYP2B6. In conclusion, the extent to which the catalytic activities of CYP were altered did not only depend on the specific POR mutations but also on the isoforms of different CYP redox partners. Thereby, we proposed that the POR-mutant patients should be carefully monitored for the activity of CYP3A4 and CYP2B6 on the prescribed medication.
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Affiliation(s)
- Xuan Chen
- Department of Pharmacology, Toxicology and Biochemical Pharmaceutics, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, China
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Abstract
PURPOSE To provide an overview of the safety and efficacy of mitomycin C (MMC) as adjuvant therapy after refractive surgery procedures. METHODS Literature review. RESULTS Over the past 10 years, MMC has been used by refractive surgeons to prophylactically decrease haze after surface ablation procedures and therapeutically in the treatment of preexisting haze. Development of MMC treatments has had a significant role in the revival of surface ablation techniques. We reviewed the literature regarding mechanism of action of MMC, its role in modulating wound healing after refractive surgery, and its safety and efficacy as adjuvant therapy applied after primary photorefractive keratectomy surgery or after photorefractive keratectomy re-treatment after laser in situ keratomileusis and other corneal surgeries and disorders. The drug is a potent mitotic inhibitor that effectively blocks keratocyte activation, proliferation, and myofibroblast differentiation. Many studies have suggested that MMC is safe and effective in doses used by anterior surface surgeons, although there continue to be concerns regarding long-term safety. After initial depletion of anterior keratocytes, keratocyte density seems to return to normal 6 to 12 months after the use of MMC when corneas are examined with the confocal microscope. Most clinical studies found no difference between preoperative and postoperative corneal endothelial cell densities when MMC 0.02% was applied during refractive surgery, with exposure time of 2 minutes or less. CONCLUSIONS After more than 10 years of use, MMC has been found to be effective when used for prevention and treatment of corneal haze. Questions remain regarding optimal treatment parameters and long-term safety.
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Gupta R, Yarnall BW, Giuliano EA, Kanwar JR, Buss DG, Mohan RR. Mitomycin C: a promising agent for the treatment of canine corneal scarring. Vet Ophthalmol 2011; 14:304-12. [PMID: 21929607 DOI: 10.1111/j.1463-5224.2011.00877.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To evaluate the safety and efficacy of mitomycin C (MMC) in prevention of canine corneal scarring. METHODS With an in vitro approach using healthy canine corneas, cultures of primary canine corneal fibroblasts or myofibroblasts were generated. Primary canine corneal fibroblasts were obtained by growing corneal buttons in minimal essential medium supplemented with 10% fetal bovine serum. Canine corneal myofibroblasts were produced by growing cultures in serum-free medium containing transforming growth factor β1 (1 ng/mL). Trypan blue assay and phase-contrast microscopy were used to evaluate the toxicity of three doses of MMC (0.002%, 0.02% and 0.04%). Real-time PCR, immunoblot, and immunocytochemistry techniques were used to determine MMC efficacy to inhibit markers of canine corneal scarring. RESULTS A single 2-min treatment of 0.02% or less MMC did not alter canine corneal fibroblast or keratocyte phenotype, viability, or growth. The 0.02% dose substantially reduced myofibroblast formation (up to 67%; P < 0.001), as measured by the change in RNA and protein expression of fibrosis biomarkers (α-smooth muscle actin and F-actin). CONCLUSION This in vitro study suggests that a single 2-min 0.02% MMC treatment to the canine corneal keratocytes is safe and may be useful in decreasing canine corneal fibrous metaplasia. In vivo studies are warranted.
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Affiliation(s)
- Rangan Gupta
- Harry S. Truman Veterans Memorial Hospital, Columbia, MO, USA
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Marohnic CC, Panda SP, McCammon K, Rueff J, Masters BSS, Kranendonk M. Human cytochrome P450 oxidoreductase deficiency caused by the Y181D mutation: molecular consequences and rescue of defect. Drug Metab Dispos 2009; 38:332-40. [PMID: 19884324 DOI: 10.1124/dmd.109.030445] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Patients with congenital adrenal hyperplasia, exhibiting combined CYP17 and CYP21 deficiency, were shown by Arlt et al. (2004) to harbor a 541T-->G mutation in exon 5 of POR (encoding NADPH-cytochrome P450 reductase, CYPOR), which resulted in a Y181D substitution that obliterated electron transfer capacity. Using bacterial expression models, we examined catalytic and physical properties of the human CYPOR Y181D variant. As purified, Y181D lacked flavin mononucleotide (FMN) and NADPH-cytochrome c reductase (NCR) activity but retained normal flavin adenine dinucleotide binding and NADPH utilization. Titration of the purified protein with FMN restored 64 of wild-type (WT) NCR activity in Y181D with an activation constant of approximately 2 microM. As determined by FMN fluorescence quenching, Y181D had K(d)(FMN) = 7.3 microM. Biplasmid coexpression of CYPOR and CYP1A2, at the physiological ratio of approximately 1:10 in the engineered MK_1A2_POR Escherichia coli strain, showed the compromised capacity of Y181D to support CYP1A2-catalyzed metabolism of the procarcinogens 2-aminoanthracene, 2-amino-3-methylimidazo(4,5-f)quinoline, and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone. Isolated MK1A2_POR membranes confirmed FMN stimulation of Y181D NCR activity with a 1.6 microM activation constant. CYP1A2 ethoxyresorufin-O-dealkylase activity of the MK1A2_POR(Y181D) membranes, undetectable in the absence of added FMN, increased to 37% of MK1A2_POR(WT) membranes with a 1.2 microM FMN activation constant. Therefore, we conclude that compromised FMN binding is the specific molecular defect causing POR deficiency in patients with Y181D mutation and that this defect, in large part, can be overcome in vitro by FMN addition.
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Affiliation(s)
- Christopher C Marohnic
- Department of Biochemistry, 7760, University of Texas Health Science Center, 7703 Floyd Curl Drive, San Antonio, TX 78229-3900, USA.
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Protective effect of melatonin against mitomycin C-induced genotoxic damage in peripheral blood of rats. J Biomed Biotechnol 2009; 2009:791432. [PMID: 19859567 PMCID: PMC2764378 DOI: 10.1155/2009/791432] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2009] [Accepted: 08/05/2009] [Indexed: 11/17/2022] Open
Abstract
Mitomycin C (MMC) generates free radicals when metabolized. We investigated the effect of melatonin against MMC-induced genotoxicity in polychromatic erythrocytes and MMC-induced lipid peroxidation in brain and liver homogenates. Rats (N = 36) were classified into 4 groups: control, melatonin, MMC, and MMC + melatonin. Melatonin and MMC doses of
10 mg/kg and 2 mg/kg, respectively, were injected intraperitoneally. Peripheral blood samples were collected at 0, 24, 48, 72, and 96 hours posttreatment and homogenates were obtained at 96 hours posttreatment. The number of micronucleated polychromatic erythrocytes (MN-PCE) per 1000 PCE was used as a genotoxic marker. Malondialdehyde (MDA) plus 4-hydroxyalkenal (4-HDA) levels were used as an index of lipid peroxidation. The MMC group showed a significant increase in MN-PCE at 24, 48, 72, and 96 hours that was significantly reduced with melatonin begin coadministrated. No significant differences were found in lipid peroxidation. Our results indicate that MMC-induced genotoxicity can be reduced by melatonin.
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Abstract
Mitomycin C has played a deciding role in the current revival of excimer laser surface ablation techniques. We review the literature regarding mechanism of action of mitomycin C, histological effects on the cornea, and indications, dose, exposure time, and toxicity of mitomycin C in corneal refractive surgery. Mitomycin C is an alkylating agent with cytotoxic and antiproliferative effects that reduces the myofibroblast repopulation after laser surface ablation and, therefore, reduces the risk of postoperative corneal haze. It is used prophylactically to avoid haze after primary surface ablation and therapeutically to treat pre-existing haze. There is no definite evidence that establishes an exact diopter limit or ablation depth at which to apply prophylactic mitomycin C. It is usually applied at a concentration of 0.2mg/ml (0.02%) for 12 to 120 seconds over the ablated stroma, although some studies suggest that lower concentrations (0.01%, 0.002%) could also be effective in preventing haze when treating low to moderate myopia. This dose of mitomycin C has not been associated with any clinically relevant epithelial corneal toxicity. Its effect on the endothelium is more controversial: two studies report a decrease in endothelial cell density, but the majority of reports suggest that the endothelium is not altered. Regarding mitomycin C's effect on keratocyte population, although animal studies report keratocyte depletion after its use, longer follow-up suggested that the initial keratocyte depletion does not persist over time.
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Hart SN, Zhong XB. P450 oxidoreductase: genetic polymorphisms and implications for drug metabolism and toxicity. Expert Opin Drug Metab Toxicol 2008; 4:439-52. [PMID: 18433346 DOI: 10.1517/17425255.4.4.439] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
BACKGROUND Cytochrome P450 oxidoreductase (POR) is the only electron donor for all microsomal cytochrome P450 monooxygenases (CYP), some of which are phase I drug-metabolizing enzymes, responsible for oxidation of more than 80% of drugs. OBJECTIVES To provide a more thorough understanding of the genetic factors influencing drug metabolism, we address the role of genetic polymorphisms in the POR gene, and their implications for drug metabolism and cytotoxicity. METHODS The scope of this review is intended to cover polymorphisms currently identified in the POR gene, assess their functional significance on POR activity, and address their impact on CYP-mediated drug metabolism. POR is also responsible for directly metabolizing several anticancer prodrugs via a 1-electron reduction reaction, so the effect of POR polymorphisms on the direct bioactivation of drugs is also considered. RESULTS/CONCLUSION POR is a polymorphic enzyme that can affect CYP-mediated drug metabolism as well as direct bioactivation of prodrugs. Genetic polymorphisms in the POR gene may help to explain altered drug-metabolizing phenotypes.
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Affiliation(s)
- Steven N Hart
- University of Kansas Medical Center, Department of Pharmacology, Toxicology, and Therapeutics, 3901 Rainbow Boulevard, Kansas City, Kansas 66160, USA
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Impairment of human CYP1A2-mediated xenobiotic metabolism by Antley-Bixler syndrome variants of cytochrome P450 oxidoreductase. Arch Biochem Biophys 2008; 475:93-9. [PMID: 18455494 DOI: 10.1016/j.abb.2008.04.014] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2008] [Revised: 04/14/2008] [Accepted: 04/15/2008] [Indexed: 01/08/2023]
Abstract
Y459H and V492E mutations of cytochrome P450 reductase (CYPOR) cause Antley-Bixler syndrome due to diminished binding of the FAD cofactor. To address whether these mutations impaired the interaction with drug-metabolizing CYPs, a bacterial model of human liver expression of CYP1A2 and CYPOR was implemented. Four models were generated: POR(null), POR(wt), POR(YH), and POR(VE), for which equivalent CYP1A2 and CYPOR levels were confirmed, except for POR(null), not containing any CYPOR. The mutant CYPORs were unable to catalyze cytochrome c and MTT reduction, and were unable to support EROD and MROD activities. Activity was restored by the addition of FAD, with V492E having a higher apparent FAD affinity than Y459H. The CYP1A2-activated procarcinogens, 2-aminoanthracene, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone, and 2-amino-3-methylimidazo(4,5-f)quinoline, were significantly less mutagenic in POR(YH) and POR(VE) models than in POR(wt), indicating that CYP1A2, and likely other drug-metabolizing CYPs, are impaired by ABS-related POR mutations as observed in the steroidogenic CYPs.
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Genetic polymorphisms in cytochrome P450 oxidoreductase influence microsomal P450-catalyzed drug metabolism. Pharmacogenet Genomics 2008; 18:11-24. [DOI: 10.1097/fpc.0b013e3282f2f121] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Flück CE, Nicolo C, Pandey AV. Clinical, structural and functional implications of mutations and polymorphisms in human NADPH P450 oxidoreductase. Fundam Clin Pharmacol 2007; 21:399-410. [PMID: 17635179 DOI: 10.1111/j.1472-8206.2007.00520.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Cytochrome P450 proteins are involved in metabolism of drugs and xenobiotics. In the endoplasmic reticulum a single nicotinamide adenine dinucleotide phosphate (NADPH) P450 oxidoreductase (POR) supplies electrons to all microsomal P450s for catalytic activity. POR is a flavoprotein that contains both flavin mononucleotide and flavin adenine dinucleotide as cofactors and uses NADPH as the source of electrons. We have recently reported a number of POR mutations in the patients with disordered steroidogenesis. In the first report we had described missense mutations (A287P, R457H, V492E, C569Y, and V608F) identified in four patients with defects in steroid production. Each POR variant was produced as recombinant N-27 form of the enzyme in bacteria and as full-length form in yeast. Membranes from bacteria or yeast expressing normal or variant POR were purified and their activities were characterized in cytochrome c and CYP17A1 assays. Later we have published a larger study that described a whole range of POR mutations and characterized the mutants/polymorphisms A115V, T142A, M263V, Y459H, A503V, G539R, L565P, R616X, V631I, and F646del from the sequencing of patient DNA. We also studied POR variants Y181D, P228L, R316W, G413S, and G504R that were available in public databases or published literature. Three-dimensional structure of rat POR is known and we have used this structure to deduce the structure-function correlation of POR mutations in human. The missense mutations found in patients with disordered steroidogenesis are generally in the co-factor binding and functionally important domains of POR and the apparent polymorphisms are found in regions with lesser structural importance. A variation in POR can alter the activity of all microsomal P450s, and therefore, can affect the metabolism of drugs and xenobiotics even when the P450s involved are otherwise normal. It is important to study the genetic and biochemical basis of POR variants in human population to gain information about possible differences in P450 mediated reactions among the individuals carrying a variant or polymorphic form of POR that could impact their metabolism.
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Affiliation(s)
- Christa E Flück
- Department of Pediatrics Endocrinology, University Children's Hospital, Freiburgstrasse 15, 3010 Bern, Switzerland
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