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Bakker J, Baum MJ. Role for estradiol in female-typical brain and behavioral sexual differentiation. Front Neuroendocrinol 2008; 29:1-16. [PMID: 17720235 PMCID: PMC2373265 DOI: 10.1016/j.yfrne.2007.06.001] [Citation(s) in RCA: 138] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/25/2007] [Revised: 05/29/2007] [Accepted: 06/19/2007] [Indexed: 12/01/2022]
Abstract
The importance of estrogens in controlling brain and behavioral sexual differentiation in female rodents is an unresolved issue in the field of behavioral neuroendocrinology. Whereas, the current dogma states that the female brain develops independently of estradiol, many studies have hinted at possible roles of estrogen in female sexual differentiation. Accordingly, it has been proposed that alpha-fetoprotein, a fetal plasma protein that binds estrogens with high affinity, has more than a neuroprotective role and specifically delivers estrogens to target brain cells to ensure female differentiation. Here, we review new results obtained in aromatase and alpha-fetoprotein knockout mice showing that estrogens can have both feminizing and defeminizing effects on the developing neural mechanisms that control sexual behavior. We propose that the defeminizing action of estradiol normally occurs prenatally in males and is avoided in fetal females because of the protective actions of alpha-fetoprotein, whereas the feminizing action of estradiol normally occurs postnatally in genetic females.
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Affiliation(s)
- Julie Bakker
- Center for Cellular & Molecular Neurobiology, University of Liège, Belgium.
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Identification of alpha-fetoprotein as an autoantigen in juvenile Batten disease. Neurobiol Dis 2007; 29:92-102. [PMID: 17931875 DOI: 10.1016/j.nbd.2007.08.007] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2007] [Revised: 07/19/2007] [Accepted: 08/12/2007] [Indexed: 01/21/2023] Open
Abstract
Humoral autoimmunity against glutamic acid decarboxylase has been described in juvenile Batten disease patients and in the Cln3(-/-) mouse model. To obtain a more comprehensive understanding of the repertoire of antigens targeted, we examined the reactivity of Cln3(-/-) mouse sera to brain proteins from fetal, postnatal and adult rats. Among the candidate antigens identified was alpha-fetoprotein (AFP), a protein that has altered expression in several nervous system disorders and hepatic malignancies. Moreover, AFP levels were upregulated in the brains and livers of postnatal day 14 Cln3(-/-) animals. Sera from 31 juvenile Batten disease patients revealed the presence of anti-AFP autoantibodies in juvenile Batten disease male patients (12/13) and female patients (8/18). While these findings provide more evidence that autoimmunity is an active component of juvenile Batten disease, the gender-apparent difference evidenced by patients with regard anti-AFP antibodies may underlie variation in progression and clinical manifestations in this disorder.
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Bakker J, De Mees C, Szpirer J, Szpirer C, Balthazart J. Exposure to oestrogen prenatally does not interfere with the normal female-typical development of odour preferences. J Neuroendocrinol 2007; 19:329-34. [PMID: 17425607 DOI: 10.1111/j.1365-2826.2007.01540.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The neural mechanisms controlling mate recognition and heterosexual partner preference are sexually differentiated by perinatal actions of sex steroid hormones. We previously showed that the most important action of oestrogen during prenatal development is to defeminise and, to some extent, masculinise brain and behaviour in mice. Female mice deficient in alpha-foetoprotein (AFP) due to a targeted mutation in the Afp gene (AFP-KO) do not show any female sexual behaviour when paired with an active male because they lack the protective action of AFP against maternal oestrogens. In the present study, we investigated whether odour preferences, another sexually differentiated trait in mice, are also defeminised and/or masculinised in AFP-KO females due to their prenatal exposure to oestrogens. AFP-KO females of two background strains (CD1 and C57Bl/6j) preferred to investigate male over female odours when given the choice between these two odour stimuli in a Y-maze, and thus remained very female-like in this regard. Thus, the absence of lordosis behaviour in these females cannot be explained by a reduced motivation of AFP-KO females to investigate male-derived odours. Furthermore, the presence of a strong male-directed odour preference in AFP-KO females suggests a postnatal contribution of oestrogens to the development of preferences to investigate opposite-sex odours.
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Affiliation(s)
- J Bakker
- Centre for Cellular and Molecular Neurobiology, University of Liège, Liège, Belgium.
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De Mees C, Bakker J, Szpirer J, Szpirer C. Alpha-fetoprotein: from a diagnostic biomarker to a key role in female fertility. Biomark Insights 2007; 1:82-5. [PMID: 19690639 PMCID: PMC2716789] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Alpha-fetoprotein (AFP) is a well-known diagnostic biomarker used in medicine to detect fetal developmental anomalies such as neural tube defects or Down's syndrome, or to follow up the development of tumors such as hepatocellular carcinomas. However, and despite the fact that the protein was discovered almost half a century ago, little was known about its physiological function. The study of Afp knock-out mice uncovered a surprising function of AFP: it is essential for female fertility and for expression of normal female behaviors, and this action is mediated through its estrogen binding capacity. AFP sequestrates estrogens and by so doing protects the female developing brain from deleterious (defeminizing/masculinizing) effects of these hormones.
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Affiliation(s)
- Christelle De Mees
- Université Libre de Bruxelles, Institut de Biologie et de Médecine Moléculaires, Rue Profs Jeener & Brachet, 12; B-6041 Gosselies (Charleroi), Belgium,Correspondence: De Mees Christelle, Université Libre de Bruxelles, institut de Biologie et de Médecine Moléculaires Rue Profs Jeener & Brachet, 12; B-6041 Gosselies (Charleroi), Belgium. Tel: +3226509703; e-mail:
| | - Julie Bakker
- University of Liège, Center for Cellular & Molecular Neurobiology, Avenue de l’Hopital 1, B36; B-4000 Liège, Belgium
| | - Josiane Szpirer
- Université Libre de Bruxelles, Institut de Biologie et de Médecine Moléculaires, Rue Profs Jeener & Brachet, 12; B-6041 Gosselies (Charleroi), Belgium
| | - Claude Szpirer
- Université Libre de Bruxelles, Institut de Biologie et de Médecine Moléculaires, Rue Profs Jeener & Brachet, 12; B-6041 Gosselies (Charleroi), Belgium
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55
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Carlini P, Ferranti P, Polizio F, Ciriolo MR, Rotilio G. Purification and characterization of Alpha-Fetoprotein from the human hepatoblastoma HepG2 cell line in serum-free medium. Biometals 2007; 20:869-78. [PMID: 17256105 DOI: 10.1007/s10534-006-9080-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2006] [Accepted: 12/28/2006] [Indexed: 11/26/2022]
Abstract
Alpha-fetoprotein (AFP) is a tumor-associated embryonic molecule whose precise biological function remains unclear. A complete definition of the physiological activities of this oncofetal protein has been severely limited, until now, by the lack of a purification procedure appropriate to obtain pure AFP in appreciable amount. The present report describes a purification procedure extremely rapid and simple and takes advantage of the well-known fact that AFP contains copper. We have developed a single-step purification procedure by immobilized copper-chelate affinity chromatography using the culture medium from human hepatoblastoma cell line HepG2 grown in the absence of serum. This method yields AFP at high purity and high yield. Purified AFP amino acid sequence, molecular mass, carbohydrate structure, and copper content were found to be in line with previous studies. Moreover, we found that the purified AFP has superoxide dismutase activity with efficiency similar to that of the native Cu, Zn SODs at physiological pH. This result may provide further support to the idea that AFP is a bifunctional protein, acting in cellular defence against oxidative stress both as a copper buffer and as a superoxide radical scavenger.
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Affiliation(s)
- Patrizia Carlini
- Department of Biology, University of Rome Tor Vergata, Rome, Italy
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Qin SW, Zhao LF, Chen XG, Xu CS. Expression pattern and action analysis of genes associated with the responses to chemical stimuli during rat liver regeneration. World J Gastroenterol 2006; 12:7285-91. [PMID: 17143942 PMCID: PMC4087484 DOI: 10.3748/wjg.v12.i45.7285] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [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 study the genes associated with the responses to chemokines, nutrients, inorganic substances, organic substances and xenobiotics after rat partial hepatectomy (PH) at transcriptional level.
METHODS: The associated genes involved in the five kinds of responses were obtained from database and literature, and the gene expression changes during liver regeneration in rats were checked by the Rat Genome 230 2.0 array.
RESULTS: It was found that 60, 10, 9, 6, 26 genes respectively participating in the above five kinds of responses were associated with liver regeneration. The numbers of initially and totally expressed genes occurring in the initial phase of liver regeneration (0.5-4 h after PH), G0/G1 transition (4-6 h after PH), cell proliferation (6-66 h after PH), cell differentiation and structure-functional reconstruction (66-168 h after PH) were 51, 19, 52, 6 and 51, 43, 98, 68 respectively, illustrating that the associated genes were mainly triggered in the initiation and transition stages, and functioned at different phases. According to their expression similarity, these genes were classified into 5 groups: only up-regulated (47), predominantly up-regulated (18), only down-regulated (24), predominantly down-regulated (10), and up- and down-regulated (8). The total times of their up-regulated and down-regulated expression were 441 and 221, demonstrating that the number of up-regulated genes is more than that of the down-regulated genes. Their time relevance and gene expression patterns were classified into 14 and 26 groups, showing that the cell physiological and biochemical activities were staggered, diversified and complicated during liver regeneration in rats.
CONCLUSION: The chemotaxis was enhanced mainly in the forepart and metaphase of LR. The response of regenerating liver to nutrients and chemical substances was increased, whereas that to xenobiotics was not strong. One hundred and seven genes associated with LR play important roles in the responses to chemical substances.
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Affiliation(s)
- Shao-Wei Qin
- Laboratory for Cell Differentiation Regulation, Xinxiang 453007, Henan Province, China
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57
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Bakker J. [Alpha-fetoprotein protects the developing female mouse brain from masculinization and defeminization by estrogens]. Med Sci (Paris) 2006; 22:459-61. [PMID: 16687103 DOI: 10.1051/medsci/2006225459] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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58
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Kwon GS, Fraser ST, Eakin GS, Mangano M, Isern J, Sahr KE, Hadjantonakis AK, Baron MH. Tg(Afp-GFP) expression marks primitive and definitive endoderm lineages during mouse development. Dev Dyn 2006; 235:2549-58. [PMID: 16708394 PMCID: PMC1850385 DOI: 10.1002/dvdy.20843] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Alpha-fetoprotein (Afp) is the most abundant serum protein in the developing embryo. It is secreted by the visceral endoderm, its derivative yolk sac endoderm, fetal liver hepatocytes, and the developing gut epithelium. The abundance of this protein suggested that Afp gene regulatory elements might serve to effectively drive reporter gene expression in developing endodermal tissues. To this end, we generated transgenic mouse lines Tg(Afp-GFP) using an Afp promoter/enhancer to drive expression of green fluorescent protein (GFP). Bright GFP fluorescence allowed the visualization, in real time, of visceral endoderm, yolk sac endoderm, fetal liver hepatocytes, and the epithelium of the gut and pancreas. Comparison of the localization of green fluorescence with that of endogenous Afp transcripts and protein indicated that the regulatory elements used to generate these mouse lines directed transgene expression in what appeared to be all Afp-expressing cells of the embryo, but only in a subset of fetal liver cells. The bright GFP signal permitted flow cytometric analysis of fetal liver hepatocytes. These mice represent a valuable resource for live imaging as well as identification, quantitation, and isolation of cells from the primitive and definitive endoderm lineages of the developing mouse embryo.
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Affiliation(s)
- Gloria S. Kwon
- Developmental Biology Program, Sloan-Kettering Institute, New York, NY
- Neurosciences Program, Weill Graduate School of Medical Sciences of Cornell University, New York, NY
| | - Stuart T. Fraser
- Department of Medicine, Mount Sinai School of Medicine, New York, NY
| | - Guy S. Eakin
- Developmental Biology Program, Sloan-Kettering Institute, New York, NY
| | - Michael Mangano
- Department of Medicine, Mount Sinai School of Medicine, New York, NY
| | - Joan Isern
- Department of Medicine, Mount Sinai School of Medicine, New York, NY
| | - Kenneth E. Sahr
- Department of Medicine, Mount Sinai School of Medicine, New York, NY
| | - Anna-Katerina Hadjantonakis
- Developmental Biology Program, Sloan-Kettering Institute, New York, NY
- * Corresponding authors: Margaret H. Baron, Mount Sinai School of Medicine, Box 1079, Departments of Medicine and Molecular, Cell & Developmental Biology, 1425 Madison Avenue 11-70B, New York, NY 10029, , Anna-Katerina Hadjantonakis, Developmental Biology Program, Sloan-Kettering Institute, Box 371, 1275 York Avenue, New York, NY 10021,
| | - Margaret H. Baron
- Department of Medicine, Mount Sinai School of Medicine, New York, NY
- Department of Molecular, Cellular and Developmental Biology, Mount Sinai School of Medicine, New York, NY
- Department of Oncological Sciences, Mount Sinai School of Medicine, New York, NY
- Department of Gene and Cell Medicine, Mount Sinai School of Medicine, New York, NY
- Black Family Stem Cell Institute, Mount Sinai School of Medicine, New York, NY
- * Corresponding authors: Margaret H. Baron, Mount Sinai School of Medicine, Box 1079, Departments of Medicine and Molecular, Cell & Developmental Biology, 1425 Madison Avenue 11-70B, New York, NY 10029, , Anna-Katerina Hadjantonakis, Developmental Biology Program, Sloan-Kettering Institute, Box 371, 1275 York Avenue, New York, NY 10021,
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59
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Interaction between Alpha-Fetoprotein Gene and Gonadotropin-Releasing Hormone and Effects on Brain Sexual Differentation: Molecular Function and Biological Process. SEXUALITY AND DISABILITY 2006. [DOI: 10.1007/s11195-006-9017-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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60
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Terentiev AA, Moldogazieva NT. Structural and functional mapping of alpha-fetoprotein. BIOCHEMISTRY (MOSCOW) 2006; 71:120-32. [PMID: 16489915 DOI: 10.1134/s0006297906020027] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Alpha-fetoprotein (AFP) is a major mammalian oncofetal protein, which is also present in small quantities in adults. It is a member of the albuminoid gene superfamily, which consists of AFP, serum albumin, vitamin D binding protein, and alpha-albumin (afamin). Although physicochemical and immunological properties of AFP have been well-studied, its biological role in embryo- and carcinogenesis and in adult organisms as well as mechanisms underlying its functioning remain unclear. During the recent decades, the biological role of AFP has been evaluated by identification of its functionally important sites. Comparison of primary structure of AFP and some physiologically active proteins revealed similarity of some polypeptide regions. This has been used for prediction of AFP functions (i.e., its multifunctionality). Localization of functionally important sites followed by determination of their amino acid composition and type of biological activity has provided valuable information for structural-functional mapping of AFP. Some peptide fragments of AFP have been synthesized and tested for biological activity. This review summarizes data on structural-functional interrelationships. We also describe functionally important AFP sites found by various groups during the last decade of structural-functional mapping of AFP with experimentally confirmed and putative biologically active sites.
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Affiliation(s)
- A A Terentiev
- Russian State Medical University, 117997 Moscow, Russia.
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61
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De Mees C, Laes JF, Bakker J, Smitz J, Hennuy B, Van Vooren P, Gabant P, Szpirer J, Szpirer C. Alpha-fetoprotein controls female fertility and prenatal development of the gonadotropin-releasing hormone pathway through an antiestrogenic action. Mol Cell Biol 2006; 26:2012-8. [PMID: 16479017 PMCID: PMC1430253 DOI: 10.1128/mcb.26.5.2012-2018.2006] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
It has been shown previously that female mice homozygous for an alpha-fetoprotein (AFP) null allele are sterile as a result of anovulation, probably due to a defect in the hypothalamic-pituitary axis. Here we show that these female mice exhibit specific anomalies in the expression of numerous genes in the pituitary, including genes involved in the gonadotropin-releasing hormone pathway, which are underexpressed. In the hypothalamus, the gonadotropin-releasing hormone gene, Gnrh1, was also found to be down-regulated. However, pituitary gene expression could be normalized and fertility could be rescued by blocking prenatal estrogen synthesis using an aromatase inhibitor. These results show that AFP protects the developing female brain from the adverse effects of prenatal estrogen exposure and clarify a long-running debate on the role of this fetal protein in brain sexual differentiation.
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Affiliation(s)
- Christelle De Mees
- Université Libre de Bruxelles, IBMM, Laboratoire de Biologie du Développement, Rue Pr. Jeener & Brachet 12, B-6041 Gosselies (Charleroi), Belgium.
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62
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Bakker J, De Mees C, Douhard Q, Balthazart J, Gabant P, Szpirer J, Szpirer C. Alpha-fetoprotein protects the developing female mouse brain from masculinization and defeminization by estrogens. Nat Neurosci 2006; 9:220-6. [PMID: 16388309 DOI: 10.1038/nn1624] [Citation(s) in RCA: 195] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2005] [Accepted: 12/06/2005] [Indexed: 11/08/2022]
Abstract
Two clearly opposing views exist on the function of alpha-fetoprotein (AFP), a fetal plasma protein that binds estrogens with high affinity, in the sexual differentiation of the rodent brain. AFP has been proposed to either prevent the entry of estrogens or to actively transport estrogens into the developing female brain. The availability of Afp mutant mice (Afp(-/-)) now finally allows us to resolve this longstanding controversy concerning the role of AFP in brain sexual differentiation, and thus to determine whether prenatal estrogens contribute to the development of the female brain. Here we show that the brain and behavior of female Afp(-/-) mice were masculinized and defeminized. However, when estrogen production was blocked by embryonic treatment with the aromatase inhibitor 1,4,6-androstatriene-3,17-dione, the feminine phenotype of these mice was rescued. These results clearly demonstrate that prenatal estrogens masculinize and defeminize the brain and that AFP protects the female brain from these effects of estrogens.
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Affiliation(s)
- Julie Bakker
- Center for Cellular & Molecular Neurobiology, University of Liège, Avenue de l'Hôpital 1, B36, 4000 Liège, Belgium.
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63
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Ishii T, Yasuchika K, Fujii H, Hoppo T, Baba S, Naito M, Machimoto T, Kamo N, Suemori H, Nakatsuji N, Ikai I. In vitro differentiation and maturation of mouse embryonic stem cells into hepatocytes. Exp Cell Res 2005; 309:68-77. [PMID: 16009362 DOI: 10.1016/j.yexcr.2005.05.028] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2005] [Revised: 05/25/2005] [Accepted: 05/29/2005] [Indexed: 01/12/2023]
Abstract
It is difficult to induce the maturation of embryonic stem (ES) cells into hepatocytes in vitro. We previously reported that Thy1-positive mesenchymal cells derived from the mouse fetal liver promote the maturation of hepatic progenitor cells. Here, we isolated alpha-fetoprotein (AFP)-producing cells from mouse ES cells for subsequent differentiation into hepatocytes in vitro by coculture with Thy1-positive cells. ES cells expressing green fluorescent protein (GFP) under the control of an AFP promoter were cultured under serum- and feeder layer-free culture conditions. The proportion of GFP-positive cells plateaued at 41.6 +/- 12.2% (means +/- SD) by day 7. GFP-positive cells, isolated by flow cytometry, were cultured in the presence or absence of Thy1-positive cells as a feeder layer. Isolated GFP-positive cells were stained for AFP, Foxa2, and albumin. The expression of mRNAs encoding tyrosine amino transferase, tryptophan 2,3-dioxygenase, and glucose-6-phosphatase were only detected following coculture with Thy1-positive cells. Following coculture with Thy1-positive cells, the isolated cells produced and stored glycogen. Ammonia clearance activity was also enhanced following coculture. Electron microscopic analysis indicated that the cocultured cells exhibited the morphologic features of mature hepatocytes. In conclusion, coculture with Thy1-positive cells in vitro induced the maturation of AFP-producing cells isolated from ES cell cultures into hepatocytes.
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Affiliation(s)
- Takamichi Ishii
- Department of Gastroenterological Surgery, Kyoto University Graduate School of Medicine, 54 Kawahara-cho Shogoin, Sakyo-ku, Kyoto, 606-8507, Japan
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Tan EH, Hooi SC, Laban M, Wong E, Ponniah S, Wee A, Wang ND. CCAAT/Enhancer Binding Protein α Knock-in Mice Exhibit Early Liver Glycogen Storage and Reduced Susceptibility to Hepatocellular Carcinoma. Cancer Res 2005; 65:10330-7. [PMID: 16288022 DOI: 10.1158/0008-5472.can-04-4486] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The CCAAT/enhancer binding protein alpha (C/EBPalpha) is vital for establishing normal hepatic energy homeostasis and moderating hepatocellular growth. CEBPA loss-of-function mutations identified in acute myeloid leukemia patients support a tumor suppressor role for C/EBPalpha. Recent work showed reductions of C/EBPalpha levels in human hepatocellular carcinoma with the reductions correlating to tumor size and progression. We investigated the potential of reactivating c/ebpalpha expression during hepatic carcinogenesis to prevent tumor cell growth. We have developed a c/ebpalpha knock-in mouse in which a single-copy c/ebpalpha is regulated by one allele of the alpha-fetoprotein (AFP) gene promoter. The knock-in mice are physically indistinguishable from wild-type (WT) controls. However, knock-in animals were found to deposit fetal hepatic glycogen earlier than WT animals. Quantitative real-time PCR confirmed early c/ebpalpha expression and early glycogen synthase gene activation in knock-in fetuses. We then used diethylnitrosamine to induce hepatocellular carcinoma in our animals. Diethylnitrosamine produced half the number of hepatocellular nodules in knock-in mice as in WT mice. Immunohistochemistry showed reduced C/EBPalpha content in WT nodules whereas knock-in nodules stained strongly for C/EBPalpha. The p21 protein was examined because it mediates a C/EBPalpha growth arrest pathway. Nuclear p21 was absent in WT nodules whereas cytoplasmic p21 was abundant; knock-in nodules were positive for nuclear p21. Interestingly, only C/EBPalpha-positive nodules were positive for nuclear p21, suggesting that C/EBPalpha may be required to direct p21 to the cell nucleus to inhibit growth. Our data establish that controlled C/EBPalpha production can inhibit liver tumor growth in vivo.
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Affiliation(s)
- Ee Hong Tan
- Department of Physiology, National University of Singapore, Singapore
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65
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Li MS, Ma QL, Chen Q, Liu XH, Li PF, Du GG, Li G. Alpha-fetoprotein triggers hepatoma cells escaping from immune surveillance through altering the expression of Fas/FasL and tumor necrosis factor related apoptosis-inducing ligand and its receptor of lymphocytes and liver cancer cells. World J Gastroenterol 2005; 11:2564-9. [PMID: 15849812 PMCID: PMC4305744 DOI: 10.3748/wjg.v11.i17.2564] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.0] [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 mechanism of α-fetoprotein (AFP) in escaping from the host immune surveillance of hepatoc-ellular carcinoma.
METHODS: AFP purified from human umbilical blood was administrated into the cultured human lymphoma Jurkat T cell line or hepatoma cell line, Bel7402 in vitro. The expression of tumor necrosis factor related apoptosis-inducing ligand (TRAIL) and its receptor (TRAILR) mRNA were analyzed by Northern blot and Western blot was used to detect the expression of Fas and Fas ligand (FasL) protein.
RESULTS: AFP (20 mg/L) could promote the expression of FasL and TRAIL, and inhibit the expression of Fas and TRAILR of Bel7402 cells. For Jurkat cell line, AFP could suppress the expression of FasL and TRAIL, and stimulate the expression of Fas and TRAILR. AFP also could synergize with Bel7402 cells to inhibit the expression of FasL protein and TRAIL mRNA in Jurkat cells. The monoclonal antibody against AFP (anti-AFP) could abolish these functions of AFP.
CONCLUSION: AFP is able to promote the expression of FasL and TRAIL in hepatoma cells and enhance the expression of Fas and TRAILR in lymphocytes. These could elicit the escape of hepatocellular carcinoma cells from the host’s lymphocytes immune surveillance.
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Affiliation(s)
- Meng-Sen Li
- Department of Biochemistry, Hainan Medical College, Haikou, China.
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66
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Cavin LG, Venkatraman M, Factor VM, Kaur S, Schroeder I, Mercurio F, Beg AA, Thorgeirsson SS, Arsura M. Regulation of α-Fetoprotein by Nuclear Factor-κB Protects Hepatocytes from Tumor Necrosis Factor-α Cytotoxicity during Fetal Liver Development and Hepatic Oncogenesis. Cancer Res 2004; 64:7030-8. [PMID: 15466196 DOI: 10.1158/0008-5472.can-04-1647] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Nuclear factor-kappaB (NF-kappaB) plays a critical role during fetal liver development and hepatic oncogenesis. Here, we have assessed whether NF-kappaB activity is required for murine hepatocellular carcinoma cell survival. We show that adenoviral-mediated inhibition of inhibitor of NF-kappaB kinase-beta (IKK-2) activity in hepatocellular carcinomas derived from transforming growth factor (TGF)-alpha/c-myc bitransgenic mice leads to inhibition of NF-kappaB and promotes tumor necrosis factor (TNF)-alpha-mediated cell death of malignant hepatocytes but not the surrounding peritumorous tissue. Induction of apoptosis is accompanied by inhibition of Bcl-X(L) and XIAP, two pro-survival NF-kappaB target genes. In addition, we have identified the alpha-fetoprotein (AFP) as a novel downstream target of NF-kappaB. We show that repression of IKK-2 activity in hepatocellular carcinomas promotes down-regulation of AFP gene expression. Likewise, genetic disruption of the RelA subunit results in reduced AFP gene expression during embryonic liver development, at a time in which fetal hepatocytes are sensitized to TNF-alpha-mediated cell killing. In this regard, we show that AFP inhibits TNF-alpha-induced cell death of murine hepatocellular carcinomas through association with TNF-alpha and inhibition of TNFRI signaling. Thus, NF-kappaB-mediated regulation of AFP gene expression during liver tumor formation and embryonic development of the liver constitutes a potential novel mechanism used by malignant and fetal hepatocytes to evade immune surveillance.
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Affiliation(s)
- Lakita G Cavin
- Department of Pharmacology, Center for Anticancer Drug Research, University of Tennessee Cancer Institute, College of Medicine, Memphis, Tennessee 38163, USA
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Abstract
Alpha-fetoprotein (AFP) is the main fetus serum glycoprotein with a very low concentration in the adult. AFP deficiency is a rare phenomenon. We studied two families with congenital AFP deficiency and searched for mutations in the AFP gene. We identified one mutation of 2 base deletion in exon 8, in both families, that leads to the congenital deficiency of AFP. The mutation nt930-931delCT (T294fs25X) creates a frameshift after codon 294 that leads to a stop codon after 24 amino acids, thus truncating the normal length of AFP of 609 amino acids. All the affected children were found to be homozygous for the mutation as was one of the fathers. The affected individuals were asymptomatic and presented normal development. This first identification of a mutation in the AFP gene demonstrates for the first time that deficiency of AFP is compatible with human normal fetal development and further reproduction in males.
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Affiliation(s)
- Reuven Sharony
- The Genetic Institute, Sapir Medical Center - Meir Hospital, Kfar Saba 44281, Israel
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68
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Mizejewski GJ. Biological roles of alpha-fetoprotein during pregnancy and perinatal development. Exp Biol Med (Maywood) 2004; 229:439-63. [PMID: 15169963 DOI: 10.1177/153537020422900602] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The use of alpha-fetoprotein (AFP) as a serum marker in cancer actually predates its employment in the detection of congenital defects; however, the latter use of AFP as a fetal defect marker has propelled its clinical utilization. Although the serum-marker capacity of AFP has long been exploited, less is known of the biological activities of this oncofetal protein during fetal and perinatal development. In the present review, the biological activities of AFP are discussed in light of this glycoprotein's presence in various biological fluid compartments: embryonic and fetal tissues, serum, urine, and reproductive fluids. After a review of the histochemical detection of AFP in various cells and tissues during development, AFP concentrations within various biological fluids were discussed in the context of gestational age and anatomic location. Discussion follows concerning the relationships and roles of AFP in developmental events such as erthyropoiesis, histogenesis/organogenesis, and ligand binding and in developmental disorders such as hypothyroidism, folate deficiencies, and acquired immunodeficiency disorder (AIDS). Based on its association with so many types of birth defects, malformations, and congenital anomalies, AFP can be viewed as a molecular "troubleshooter" until signal transduction pathways are established during pregnancy and prenatal development. The review concludes with a discussion of the place of AFP in the rapidly expanding field of proteomics.
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Affiliation(s)
- Gerald J Mizejewski
- Division of Molecular Medicine, Wadsworth Center, New York State Department of Health, Empire State Plaza, Albany, New York 12201, USA.
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69
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Park KY, Sellars EA, Grinberg A, Huang SP, Pfeifer K. The H19 differentially methylated region marks the parental origin of a heterologous locus without gametic DNA methylation. Mol Cell Biol 2004; 24:3588-95. [PMID: 15082756 PMCID: PMC387767 DOI: 10.1128/mcb.24.9.3588-3595.2004] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Igf2 and H19 are coordinately regulated imprinted genes physically linked on the distal end of mouse chromosome 7. Genetic analyses demonstrate that the differentially methylated region (DMR) upstream of the H19 gene is necessary for three distinct functions: transcriptional insulation of the maternal Igf2 allele, transcriptional silencing of paternal H19 allele, and marking of the parental origin of the two chromosomes. To test the sufficiency of the DMR for the third function, we inserted DMR at two heterologous positions in the genome, downstream of H19 and at the alpha-fetoprotein locus on chromosome 5. Our results demonstrate that the DMR alone is sufficient to act as a mark of parental origin. Moreover, this activity is not dependent on germ line differences in DMR methylation. Thus, the DMR can mark its parental origin by a mechanism independent of its own DNA methylation.
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Affiliation(s)
- Kye-Yoon Park
- Laboratory of Mammalian Genes and Development, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892, USA
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70
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Mizejewski GJ. Levels of alpha-fetoprotein during pregnancy and early infancy in normal and disease states. Obstet Gynecol Surv 2004; 58:804-26. [PMID: 14668662 DOI: 10.1097/01.ogx.0000099770.97668.18] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Alpha-fetoprotein (AFP) was 1 of the first serum protein markers to serve in the dual capacities of tumor marker and fetal defect marker, ie, an oncofetal protein, in the clinical laboratory. Although the serum-marker capacity of AFP has long been used, less is known of the fluid compartments of this oncofetal protein during fetal and perinatal development. In this review, the biologic activities of AFP are discussed in light of its presence in the various biologic fluid compartments: fetal serum, amniotic fluid, cord blood, urine, and maternal serum. AFP concentrations within the biologic fluids are considered in the context of gestational age, sex, body weight, and anatomic location. Discussion follows concerning the relationships and roles of AFP in various developmental disorders such as hypothyroidism, folate deficiencies, autoimmune disorders, acquired immunodeficiency disorder (AIDS), congenital heart defects, cystic fibrosis, preeclampsia/hypertension, and platelet aggregation disorders. Based on its presence in so many types of birth defects, malformations, and congenital anomalies, AFP can be seen to serve as a form of molecular "duct tape" during pregnancy and postnatal development.
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Affiliation(s)
- Gerald J Mizejewski
- Division of Molecular Medicine, Wadsworth Center, New York State Department of Health, Albany 12201, USA.
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71
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Li MS, Li PF, Chen Q, Du GG, Li G. Alpha-fetoprotein stimulated the expression of some oncogenes in human hepatocellular carcinoma Bel 7402 cells. World J Gastroenterol 2004; 10:819-24. [PMID: 15040024 PMCID: PMC4726995 DOI: 10.3748/wjg.v10.i6.819] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
AIM: To investigate the molecular mechanism of alpha-fetoprotein (AFP) on regulating the proliferation of human hepatocellular carcinoma cells.
METHODS: Alpha-fetoprotein purified from human umbilical blood was added to cultured human hepatocellular carcinoma Bel 7402 cells in vitro for various treatment periods. The expression of c-fos, c-jun, and N-ras mRNA involved in proliferation and differentiation of cells was analyzed by Northern blot, and the expression of mutative p53 and p21ras proteins was determined by Western blot.
RESULTS: The results showed that AFP (20 mg/L) stimulated mRNA expression of these oncogenes in Bel 7402 cells. The expression of c-fos mRNA increased by 51.1%, 60.9%, 96.0%, and 25.5% at 2, 6, 12, and 24 h, respectively. The expression of c-jun and N-ras mRNA reached to the maximum which increased by 81.3% and 59.9% as compared with the control after 6 h and 24 h incubation with AFP, respectively. Western blot assay also demonstrated that AFP promoted the expression of mutative p53 and p21ras proteins, and the increased rate of those proteins was 13.0%, 39.9%, and 70.9%, as well as 35.2%, 102.6%, and 46.8% at 6, 12, and 24 h, respectively, as compared with the control. Both human serum albumin (the same dosage as AFP) and monoclonal anti-AFP antibody failed to stimulate the expression of these oncogenes, but anti-AFP antibody could block the functions of AFP.
CONCLUSION: The data indicate that AFP can stimulate the expression of some oncogenes to enhance the proliferation of human hepatocellular carcinoma Bel 7402 cells.
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Affiliation(s)
- Meng-Sen Li
- Department of Biochemistry, Hainan Medical College, Haikou 571101, China.
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Semenkova L, Dudich E, Dudich I, Tokhtamisheva N, Tatulov E, Okruzhnov Y, Garcia-Foncillas J, Palop-Cubillo JA, Korpela T. Alpha-fetoprotein positively regulates cytochrome c-mediated caspase activation and apoptosome complex formation. ACTA ACUST UNITED AC 2003; 270:4388-99. [PMID: 14622304 DOI: 10.1046/j.1432-1033.2003.03836.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Previous results have shown that the oncoembryonic marker alpha-fetoprotein (AFP) is able to induce apoptosis in tumor cells through activation of caspase 3, bypassing Fas-dependent and tumor necrosis factor receptor-dependent signaling. In this study we further investigate the molecular interactions involved in the AFP-mediated signaling of apoptosis. We show that AFP treatment of tumor cells is accompanied by cytosolic translocation of mitochondrial cytochrome c. In a cell-free system, AFP mediates processing and activation of caspases 3 and 9 by synergistic enhancement of the low-dose cytochrome c-mediated signals. AFP was unable to regulate activity of caspase 3 in cell extracts depleted of cytochrome c or caspase 9. Using high-resolution chromatography, we show that AFP positively regulates cytochrome c/dATP-mediated apoptosome complex formation, enhances recruitment of caspases and Apaf-1 into the complex, and stimulates release of the active caspases 3 and 9 from the apoptosome. By using a direct protein-protein interaction assay, we show that pure human AFP almost completely disrupts the association between processed caspases 3 and 9 and the cellular inhibitor of apoptosis protein (cIAP-2), demonstrating its release from the complex. Our data suggest that AFP may regulate cell death by displacing cIAP-2 from the apoptosome, resulting in promotion of caspase 3 activation and its release from the complex.
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73
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Jiang Z, Zhang M, Wasem VD, Michal JJ, Zhang H, Wright RW. Census of genes expressed in porcine embryos and reproductive tissues by mining an expressed sequence tag database based on human genes. Biol Reprod 2003; 69:1177-82. [PMID: 12826578 DOI: 10.1095/biolreprod.103.018127] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
A total of 98,898 expressed sequence tags (ESTs) derived from embryos and reproductive tissues in pigs were identified in the GenBank "est_others" database. Pig embryos were collected at 11, 12, 13, 14, 15, 20, 30, and 45 days after gestation. The reproductive tissues were sampled from testis, ovary, endometrium, hypothalamus, anterior pituitary, uterus, and placenta. A gene-oriented approach was developed to annotate these porcine EST sequences to census the genes expressed from these sources. Of the 33 308 mRNA sequences from the human genes used as references (data accessed on 1 November 2002), 9410 had the porcine EST homologs expressed in embryos and 11 795 had the EST homologs expressed in reproductive tissues. The entire genome contributes at least 28.3% of its genes to embryo development and 35.4% of its genes to reproduction. Using the EST entry numbers as indicators of gene expression, we determined that the gene expression patterns differ significantly between embryos and reproductive tissues in pigs. The basic active genes were identified for each source, but most of them are not coexpressed abundantly. Few genes were expressed on the Y chromosome (P < 0.01), but they may represent counterparts of the double-dose genes that remain active in an inactivated X chromosome in females but are needed for proper development and growth. The census provides a panel of transcripts in a broad sense that can be used as targets to study the mechanisms involved in embryo development and reproduction in pigs and other mammals, including humans.
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Affiliation(s)
- Zhihua Jiang
- Department of Animal Sciences, Washington State University, Pullman 99164, USA.
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