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Leahy C, Osborne N, Shirota L, Rote P, Lee YK, Song BJ, Yin L, Zhang Y, Garcia V, Hardwick JP. The fatty acid omega hydroxylase genes (CYP4 family) in the progression of metabolic dysfunction-associated steatotic liver disease (MASLD): An RNA sequence database analysis and review. Biochem Pharmacol 2024:116241. [PMID: 38697309 DOI: 10.1016/j.bcp.2024.116241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2024] [Revised: 04/21/2024] [Accepted: 04/25/2024] [Indexed: 05/04/2024]
Abstract
Fatty acid omega hydroxylase P450s consist of enzymes that hydroxylate various chain-length saturated and unsaturated fatty acids (FAs) and bioactive eicosanoid lipids. The human cytochrome P450 gene 4 family (CYP4) consists of 12 members that are associated with several human diseases. However, their role in the progression of metabolic dysfunction-associated fatty liver disease (MASLD) remains largely unknown. It has long been thought that the induction of CYP4 family P450 during fasting and starvation prevents FA-related lipotoxicity through FA metabolism to dicarboxylic acids that are chain-shortened in peroxisomes and then transported to the mitochondria for complete oxidation. Several studies have revealed that peroxisome succinate transported to the mitochondria is used for gluconeogenesis during fasting and starvation, and recent evidence suggests that peroxisome acetate can be utilized for lipogenesis and lipid droplet formation as well as epigenetic modification of gene transcription. In addition, omega hydroxylation of the bioactive eicosanoid arachidonic acid to 20-Hydroxyeicosatetraenoic acid (20-HETE) is essential for activating the GPR75 receptor, leading to vasoconstriction and cell proliferation. Several mouse models of diet-induced MASLD have revealed the induction of selective CYP4A members and the suppression of CYP4F during steatosis and steatohepatitis, suggesting a critical metabolic role in the progression of fatty liver disease. Thus, to further investigate the functional roles of CYP4 genes, we analyzed the differential gene expression of 12 members of CYP4 gene family in datasets from the Gene Expression Omnibus (GEO) from patients with steatosis, steatohepatitis, fibrosis, cirrhosis, and hepatocellular carcinoma. We also observed the differential expression of various CYP4 genes in the progression of MASLD, indicating that different CYP4 members may have unique functional roles in the metabolism of specific FAs and eicosanoids at various stages of fatty liver disease. These results suggest that targeting selective members of the CYP4A family is a viable therapeutic approach for treating and managing MASLD.
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Affiliation(s)
- Charles Leahy
- Department of Integrative Medical Sciences Liver focus group, Northeast Ohio Medical University, 4209 State Route 44, Rootstown, OH 44272, USA
| | - Nicholas Osborne
- Department of Integrative Medical Sciences Liver focus group, Northeast Ohio Medical University, 4209 State Route 44, Rootstown, OH 44272, USA
| | - Leticia Shirota
- Department of Integrative Medical Sciences Liver focus group, Northeast Ohio Medical University, 4209 State Route 44, Rootstown, OH 44272, USA
| | - Paula Rote
- Department of Integrative Medical Sciences Liver focus group, Northeast Ohio Medical University, 4209 State Route 44, Rootstown, OH 44272, USA
| | - Yoon-Kwang Lee
- Department of Integrative Medical Sciences Liver focus group, Northeast Ohio Medical University, 4209 State Route 44, Rootstown, OH 44272, USA
| | - Byoung-Joon Song
- Section of Molecular Pharmacology and Toxicology, National Institute on Alcohol Abuse and Alcoholism, 9000 Rockville Pike, Bethesda, MD 20892, USA
| | - Liya Yin
- Department of Integrative Medical Sciences Liver focus group, Northeast Ohio Medical University, 4209 State Route 44, Rootstown, OH 44272, USA
| | - Yanqiao Zhang
- Department of Integrative Medical Sciences Liver focus group, Northeast Ohio Medical University, 4209 State Route 44, Rootstown, OH 44272, USA
| | - Victor Garcia
- Department of Pharmacology, New York Medical College, 15 Dana Road Science Building, Rm. 530, Valhalla, NY 10595, USA
| | - James P Hardwick
- Department of Integrative Medical Sciences Liver focus group, Northeast Ohio Medical University, 4209 State Route 44, Rootstown, OH 44272, USA.
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Spotlight on CYP4B1. Int J Mol Sci 2023; 24:ijms24032038. [PMID: 36768362 PMCID: PMC9916508 DOI: 10.3390/ijms24032038] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Revised: 01/16/2023] [Accepted: 01/17/2023] [Indexed: 01/22/2023] Open
Abstract
The mammalian cytochrome P450 monooxygenase CYP4B1 can bioactivate a wide range of xenobiotics, such as its defining/hallmark substrate 4-ipomeanol leading to tissue-specific toxicities. Similar to other members of the CYP4 family, CYP4B1 has the ability to hydroxylate fatty acids and fatty alcohols. Structural insights into the enigmatic role of CYP4B1 with functions in both, xenobiotic and endobiotic metabolism, as well as its unusual heme-binding characteristics are now possible by the recently solved crystal structures of native rabbit CYP4B1 and the p.E310A variant. Importantly, CYP4B1 does not play a major role in hepatic P450-catalyzed phase I drug metabolism due to its predominant extra-hepatic expression, mainly in the lung. In addition, no catalytic activity of human CYP4B1 has been observed owing to a unique substitution of an evolutionary strongly conserved proline 427 to serine. Nevertheless, association of CYP4B1 expression patterns with various cancers and potential roles in cancer development have been reported for the human enzyme. This review will summarize the current status of CYP4B1 research with a spotlight on its roles in the metabolism of endogenous and exogenous compounds, structural properties, and cancer association, as well as its potential application in suicide gene approaches for targeted cancer therapy.
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Yu S, Chen Z, Cheng J, Shi X, Liu J, Zhong P, Song J. Case-control study on CYP4B1 gene polymorphism and susceptibility to gastric cancer in the chinese Han population. BMC Med Genomics 2022; 15:223. [PMID: 36307788 PMCID: PMC9615408 DOI: 10.1186/s12920-022-01367-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Accepted: 09/21/2022] [Indexed: 11/10/2022] Open
Abstract
Abstract
Background:
In China, gastric cancer (GC) is one of the most common malignant tumors. This study aimed to explore the relationship of rs2297810, rs4646491 and rs2297809 polymorphisms of CYP4B1 with susceptibility to GC in the Chinese Han population.
Methods:
A case-control study including 707 GC cases and 707 normal controls was conducted. Three single nucleotide polymorphisms (SNPs) were genotyped by Agena MassARRAY system. Logistic regression analysis was utilized to assess the effects of SNPs on GC risk. Furthermore, multifactor dimensionality reduction (MDR) approach was used to analyze the SNP-SNP interactions.
Results:
No significant relationships were found between rs2297810 and rs2297809 and GC risk under all genetic models. For rs4646491, people with TC genotype had a 1.40-fold higher risk of GC than those with CC genotype (OR = 1.40; 95% CI = 1.13–1.74; p = 0.002), and people with TT-TC genotype had a 1.30-fold higher risk of GC than those with CC genotype (OR = 1.30; 95% CI = 1.06–1.61; p = 0.014). Stratification results showed that GC risk in people carrying TC genotype was higher than that in people with CC genotype, males (OR = 1.36; 95% CI = 1.06–1.75; p = 0.015), non-smokers (OR = 1.52; 95% CI = 1.11–2.07; p = 0.009) and non-drinkers (OR = 1.50; 95% CI = 1.10–2.04; p = 0.010). Additionally, the study also revealed that GC risk in people carrying TT-TC genotype was higher than that in people with CC genotype, males (OR = 1.29; 95% CI = 1.01–1.64; p = 0.040), non-smokers (OR = 1.40; 95% CI = 1.04–1.89; p = 0.027) and non-drinkers (OR = 1.39; 95% CI = 1.03–1.87; p = 0.030).
Conclusion:
This study firstly found that CYP4B1-rs4646491 was significantly correlated with GC risk, and it might be a risk factor for GC.
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Cao X, Coyle JP, Xiong R, Wang Y, Heflich RH, Ren B, Gwinn WM, Hayden P, Rojanasakul L. Invited review: human air-liquid-interface organotypic airway tissue models derived from primary tracheobronchial epithelial cells-overview and perspectives. In Vitro Cell Dev Biol Anim 2020; 57:104-132. [PMID: 33175307 PMCID: PMC7657088 DOI: 10.1007/s11626-020-00517-7] [Citation(s) in RCA: 67] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Accepted: 09/29/2020] [Indexed: 02/07/2023]
Abstract
The lung is an organ that is directly exposed to the external environment. Given the large surface area and extensive ventilation of the lung, it is prone to exposure to airborne substances, such as pathogens, allergens, chemicals, and particulate matter. Highly elaborate and effective mechanisms have evolved to protect and maintain homeostasis in the lung. Despite these sophisticated defense mechanisms, the respiratory system remains highly susceptible to environmental challenges. Because of the impact of respiratory exposure on human health and disease, there has been considerable interest in developing reliable and predictive in vitro model systems for respiratory toxicology and basic research. Human air-liquid-interface (ALI) organotypic airway tissue models derived from primary tracheobronchial epithelial cells have in vivo–like structure and functions when they are fully differentiated. The presence of the air-facing surface allows conducting in vitro exposures that mimic human respiratory exposures. Exposures can be conducted using particulates, aerosols, gases, vapors generated from volatile and semi-volatile substances, and respiratory pathogens. Toxicity data have been generated using nanomaterials, cigarette smoke, e-cigarette vapors, environmental airborne chemicals, drugs given by inhalation, and respiratory viruses and bacteria. Although toxicity evaluations using human airway ALI models require further standardization and validation, this approach shows promise in supplementing or replacing in vivo animal models for conducting research on respiratory toxicants and pathogens.
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Affiliation(s)
- Xuefei Cao
- Division of Genetic and Molecular Toxicology, National Center for Toxicological Research, US Food and Drug Administration, 3900 NCTR Rd., AR, Jefferson, USA.
| | - Jayme P Coyle
- Allergy and Clinical Immunology Branch, Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Centers for Disease Control and Prevention, Morgantown, WV, USA
| | - Rui Xiong
- Division of Genetic and Molecular Toxicology, National Center for Toxicological Research, US Food and Drug Administration, 3900 NCTR Rd., AR, Jefferson, USA
| | - Yiying Wang
- Division of Genetic and Molecular Toxicology, National Center for Toxicological Research, US Food and Drug Administration, 3900 NCTR Rd., AR, Jefferson, USA
| | - Robert H Heflich
- Division of Genetic and Molecular Toxicology, National Center for Toxicological Research, US Food and Drug Administration, 3900 NCTR Rd., AR, Jefferson, USA
| | - Baiping Ren
- Division of Genetic and Molecular Toxicology, National Center for Toxicological Research, US Food and Drug Administration, 3900 NCTR Rd., AR, Jefferson, USA
| | - William M Gwinn
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, Durham, NC, USA
| | | | - Liying Rojanasakul
- Allergy and Clinical Immunology Branch, Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Centers for Disease Control and Prevention, Morgantown, WV, USA
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Lim S, Alshagga M, Ong CE, Chieng JY, Pan Y. Cytochrome P450 4B1 (CYP4B1) as a target in cancer treatment. Hum Exp Toxicol 2020; 39:785-796. [PMID: 32054340 DOI: 10.1177/0960327120905959] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Cytochrome P450 4B1 (CYP4B1) plays crucial roles in biotransforming of xenobiotics. Its predominant extrahepatic expression has been associated with certain tissue-specific toxicities. However, the expressions of CYP4B1 in various cancers and hence their potential roles in cancer development were inclusive. In this work, existing knowledge on expression and regulation of CYP4B1 gene and protein, catalysis of CYP4B1, association of CYP4B1 with cancers, contradicting findings about human CYP4B1 activities as well as the employing CYP4B1 in suicide gene approach for cancer treatment were reviewed. To date, it appears that there is a wide spectrum of tissue distribution of CYP4B1 with lungs as the predominant sites. Several nuclear receptors are possibly responsible for regulating its gene expression. The involvement of CYP4B1 in cancer was considered via activation of procarcinogens and neovascularization. However, human CYP4B1 was found to be inactive due to a substitution of proline with serine at position 427. Suicide gene approach combining reengineered CYP4B1 and prodrug 4-ipomeanol (4-IPO) has shown a promising potential for targeted cancer therapy. Further studies should focus on the verification of human CYP4B1 catalytic activities. More compounds with similar structure as 4-IPO should be tested to identify more alternative agents for the suicide gene approach in cancer treatment.
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Affiliation(s)
- Sym Lim
- Division of Biomedical Science, School of Pharmacy, University of Nottingham Malaysia, Selangor, Malaysia
| | - M Alshagga
- Division of Biomedical Science, School of Pharmacy, University of Nottingham Malaysia, Selangor, Malaysia
| | - C E Ong
- School of Pharmacy, International Medical University, Kuala Lumpur, Malaysia
| | - J Y Chieng
- Hospital Pantai Ampang, Kuala Lumpur, Malaysia
| | - Y Pan
- Division of Biomedical Science, School of Pharmacy, University of Nottingham Malaysia, Selangor, Malaysia
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6
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Xenobiotica-metabolizing enzymes in the lung of experimental animals, man and in human lung models. Arch Toxicol 2019; 93:3419-3489. [PMID: 31673725 DOI: 10.1007/s00204-019-02602-7] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Accepted: 10/15/2019] [Indexed: 12/15/2022]
Abstract
The xenobiotic metabolism in the lung, an organ of first entry of xenobiotics into the organism, is crucial for inhaled compounds entering this organ intentionally (e.g. drugs) and unintentionally (e.g. work place and environmental compounds). Additionally, local metabolism by enzymes preferentially or exclusively occurring in the lung is important for favorable or toxic effects of xenobiotics entering the organism also by routes other than by inhalation. The data collected in this review show that generally activities of cytochromes P450 are low in the lung of all investigated species and in vitro models. Other oxidoreductases may turn out to be more important, but are largely not investigated. Phase II enzymes are generally much higher with the exception of UGT glucuronosyltransferases which are generally very low. Insofar as data are available the xenobiotic metabolism in the lung of monkeys comes closed to that in the human lung; however, very few data are available for this comparison. Second best rate the mouse and rat lung, followed by the rabbit. Of the human in vitro model primary cells in culture, such as alveolar macrophages and alveolar type II cells as well as the A549 cell line appear quite acceptable. However, (1) this generalization represents a temporary oversimplification born from the lack of more comparable data; (2) the relative suitability of individual species/models is different for different enzymes; (3) when more data become available, the conclusions derived from these comparisons quite possibly may change.
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Anttila S, Raunio H, Hakkola J. Cytochrome P450-mediated pulmonary metabolism of carcinogens: regulation and cross-talk in lung carcinogenesis. Am J Respir Cell Mol Biol 2011; 44:583-90. [PMID: 21097654 DOI: 10.1165/rcmb.2010-0189rt] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2023] Open
Abstract
Lung cancer is strongly associated with exogenous risk factors, in particular tobacco smoking and asbestos exposure. New research data are accumulating about the regulation of the metabolism of tobacco carcinogens and the metabolic response to oxidative stress. These data provide mechanistic details about why well known risk factors cause lung cancer. The purpose of this review is to evaluate the present knowledge of the role of cytochrome P450 (CYP) enzymes in the metabolism of tobacco carcinogens and associations with tobacco and asbestos carcinogenesis. Major emphasis is placed on human data and regulatory pathways involved in CYP regulation and lung carcinogenesis. The most exciting new research findings concern cross-talk of the CYP-regulating aryl hydrocarbon receptor with other transcription factors, such as nuclear factor-erythroid 2-related factor 2, involved in the regulation of xenobiotic metabolism and antioxidant enzymes. This cross-talk between transcription factors may provide mechanistic evidence for clinically relevant issues, such as differences in lung cancers between men and women and the synergism between tobacco and asbestos as lung carcinogens.
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Affiliation(s)
- Sisko Anttila
- Dept. of Pathology, HUSLAB and Helsinki University Hospital, Finland.
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8
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Carlson GP. Critical appraisal of the expression of cytochrome P450 enzymes in human lung and evaluation of the possibility that such expression provides evidence of potential styrene tumorigenicity in humans. Toxicology 2008; 254:1-10. [PMID: 18951947 DOI: 10.1016/j.tox.2008.09.017] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2008] [Revised: 09/17/2008] [Accepted: 09/20/2008] [Indexed: 10/21/2022]
Abstract
Styrene is widely used with significant human exposure, particularly in the reinforced plastics industry. In mice it is both hepatotoxic and pneumotoxic, and this toxicity is generally thought to be associated with its metabolism to styrene oxide. Styrene causes lung tumors in mice but not in rats. The question is how the tumorigenic effect in mouse lung may relate to the human. This review examines the comparison of the metabolic activation rates (1) between the liver and lung and (2) for the lung, between the rodent and human. Emphasis is placed on the specific cytochromes P450 present in the lungs of humans and what role they might play in the bioactivation of styrene and other compounds. In general, pulmonary metabolism is very slow compared to hepatic metabolism. Furthermore, metabolic rates in humans are slow compared to those in rats and mice. There is a wide difference in what specific cytochromes P450 investigators have reported as being present in human lung which makes comparisons, both inter-species and inter-organ, difficult. The general low activity for cytochrome P450 activity in the lung, especially for CYP2F1, the human homolog for CYP2F2 which has been identified in mice as being primarily responsible for styrene metabolism, argues against the hypothesis that human lung would produce enough styrene oxide to damage pulmonary epithelial cells leading to cell death, increased cell replication and ultimately tumorigenicity, the presumed mode of action for styrene in the production of the mouse lung tumors.
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Affiliation(s)
- Gary P Carlson
- School of Health Sciences, Purdue University, 550 Stadium Mall Drive, West Lafayette, IN 47907-2051, United States.
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Frampton JP, Shuler ML, Shain W, Hynd MR. Biomedical Technologies for in vitro Screening and Controlled Delivery of Neuroactive Compounds. Cent Nerv Syst Agents Med Chem 2008; 8:203-219. [PMID: 19079777 PMCID: PMC2600660 DOI: 10.2174/187152408785699613] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Cell culture models can provide information pertaining to the effective dose, toxiciology, and kinetics, for a variety of neuroactive compounds. However, many in vitro models fail to adequately predict how such compounds will perform in a living organism. At the systems level, interactions between organs can dramatically affect the properties of a compound by alteration of its biological activity or by elimination of it from the body. At the tissue level, interaction between cell types can alter the transport properties of a particular compound, or can buffer its effects on target cells by uptake, processing, or changes in chemical signaling between cells. In any given tissue, cells exist in a three-dimensional environment bounded on all sides by other cells and components of the extracellular matrix, providing kinetics that are dramatically different from the kinetics in traditional two-dimensional cell culture systems. Cell culture analogs are currently being developed to better model the complex transport and processing that occur prior to drug uptake in the CNS, and to predict blood-brain barrier permeability. These approaches utilize microfluidics, hydrogel matrices, and a variety of cell types (including lung epithelial cells, hepatocytes, adipocytes, glial cells, and neurons) to more accurately model drug transport and biological activity. Similar strategies are also being used to control both the spatial and temporal release of therapeutic compounds for targeted treatment of CNS disease.
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Affiliation(s)
- John P Frampton
- Department of Biomedical Sciences, School of Public Health, University at Albany, Albany, NY, USA
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Genter MB, Yost GS, Rettie AE. Localization of CYP4B1 in the rat nasal cavity and analysis of CYPs as secreted proteins. J Biochem Mol Toxicol 2007; 20:139-41. [PMID: 16788951 DOI: 10.1002/jbt.20123] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
CYP4B1 is highly expressed in rat nasal respiratory mucosa, and to a lesser extent in olfactory mucosa. Examination of high-power photomicrographs suggests that CYP4B1 may be a secreted protein, based on the fact that immunoreactivity appears to be present in the lumens of ducts of Bowman's glands (rather than intracellular localization, as we observed with an antibody recognizing CYP2F4) and in secretory granules in respiratory mucosa. Furthermore, anti-CYP4B1 immunoreactivity is present on the surface of both respiratory and olfactory mucosa. We used SignalP 3.0 analysis to ascertain the likelihood that rat CYP4B1 is a secreted protein. While this analysis does not suggest that rat CYP4B1 is a secreted protein, several other cytochrome P450 enzymes were predicted to be secreted proteins. The observation that multiple human cytochrome P450s appear to be secreted proteins helps to explain the appearance of anti-cytochrome P450 antigens in cases of human autoimmune liver diseases.
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Affiliation(s)
- Mary Beth Genter
- Department of Environmental Health, University of Cincinnati, ML 670056, Cincinnati, OH 45267-0056, USA.
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Baer BR, Rettie AE. CYP4B1: an enigmatic P450 at the interface between xenobiotic and endobiotic metabolism. Drug Metab Rev 2006; 38:451-76. [PMID: 16877261 DOI: 10.1080/03602530600688503] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
CYP4B1 belongs to the mammalian CYP4 enzyme family that also includes CYP4A, 4F, 4V, 4X, and 4Z subfamilies. CYP4B1 shares with other CYP4 proteins a capacity to omega-hydroxylate medium-chain fatty acids, which may be related to an endogenous role for the enzyme. CYP4B1 also participates in the metabolism of certain xenobiotics that are protoxic, including valproic acid, 3-methylindole, 4-ipomeanol, 3-methoxy-4-aminoazobenzene, and numerous aromatic amines. Although these compounds have little in common structurally or chemically, their metabolism by CYP4B1 leads to tissue-specific toxicities in several experimental animals. The bioactivation capabilities of rabbit CYP4B1 have also attracted attention in the cancer community and form the basis of a potential therapeutic strategy involving prodrug activation by the CYP4B1 transgene. The metabolic capabilities of human CYP4B1 are less clear due to difficulties in heterologous expression and existence of alternatively spliced products. Also, many CYP4B1 enzymes covalently bind their heme, a posttranslational modification unique to the CYP4 family of P450s, but common to the mammalian peroxidases. These varied characteristics render CYP4B1 an interesting and enigmatic investigational target.
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Affiliation(s)
- Brian R Baer
- Department of Medicinal Chemistry, University of Washington, Seattle, Washington 98195, USA
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