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Sani F, Sani M, Moayedfard Z, Darayee M, Tayebi L, Azarpira N. Potential advantages of genetically modified mesenchymal stem cells in the treatment of acute and chronic liver diseases. Stem Cell Res Ther 2023; 14:138. [PMID: 37226279 DOI: 10.1186/s13287-023-03364-x] [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: 01/14/2023] [Accepted: 05/04/2023] [Indexed: 05/26/2023] Open
Abstract
Liver damage caused by toxicity can lead to various severe conditions, such as acute liver failure (ALF), fibrogenesis, and cirrhosis. Among these, liver cirrhosis (LC) is recognized as the leading cause of liver-related deaths globally. Unfortunately, patients with progressive cirrhosis are often on a waiting list, with limited donor organs, postoperative complications, immune system side effects, and high financial costs being some of the factors restricting transplantation. Although the liver has some capacity for self-renewal due to the presence of stem cells, it is usually insufficient to prevent the progression of LC and ALF. One potential therapeutic approach to improving liver function is the transplantation of gene-engineered stem cells. Several types of mesenchymal stem cells from various sources have been suggested for stem cell therapy for liver disease. Genetic engineering is an effective strategy that enhances the regenerative potential of stem cells by releasing growth factors and cytokines. In this review, we primarily focus on the genetic engineering of stem cells to improve their ability to treat damaged liver function. We also recommend further research into accurate treatment methods that involve safe gene modification and long-term follow-up of patients to increase the effectiveness and reliability of these therapeutic strategies.
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Affiliation(s)
- Farnaz Sani
- Hematology and Cell Therapy Department, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Mahsa Sani
- Department of Tissue Engineering and Cell Therapy, School of Advanced Technologies in Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Zahra Moayedfard
- Department of Tissue Engineering and Cell Therapy, School of Advanced Technologies in Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Maryam Darayee
- Department of Molecular Medicine, School of Advanced Medical Sciences and Technologies, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Lobat Tayebi
- Marquette University School of Dentistry, Milwaukee, WI, 53233, USA
| | - Negar Azarpira
- Transplant Research Center, Shiraz University of Medical Sciences, Khalili Street, P.O. Box: 7193711351, Shiraz, Iran.
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Choi JH, Park S, Kim GD, Kim JY, Jun JH, Bae SH, Baik SK, Hwang SG, Kim GJ. Increased Phosphatase of Regenerating Liver-1 by Placental Stem Cells Promotes Hepatic Regeneration in a Bile-Duct-Ligated Rat Model. Cells 2021; 10:cells10102530. [PMID: 34685509 PMCID: PMC8533985 DOI: 10.3390/cells10102530] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Revised: 09/17/2021] [Accepted: 09/21/2021] [Indexed: 11/16/2022] Open
Abstract
Phosphatase of regenerating liver-1 (PRL-1) controls various cellular processes and liver regeneration. However, the roles of PRL-1 in liver regeneration induced by chorionic-plate-derived mesenchymal stem cells (CP-MSCs) transplantation remain unknown. Here, we found that increased PRL-1 expression by CP-MSC transplantation enhanced liver regeneration in a bile duct ligation (BDL) rat model by promoting the migration and proliferation of hepatocytes. Engrafted CP-MSCs promoted liver function via enhanced hepatocyte proliferation through increased PRL-1 expression in vivo and in vitro. Moreover, higher increased expression of PRL-1 regulated CP-MSC migration into BDL-injured rat liver through enhancement of migration-related signals by increasing Rho family proteins. The dual effects of PRL-1 on proliferation of hepatocytes and migration of CP-MSCs were substantially reduced when PRL-1 was silenced with siRNA-PRL-1 treatment. These findings suggest that PRL-1 may serve as a multifunctional enhancer for therapeutic applications of CP-MSC transplantation.
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Affiliation(s)
- Jong Ho Choi
- Department of Oral Pathology, College of Dentistry, Gangneung-Wonju National University, Gangneung-si 25457, Korea;
| | - Sohae Park
- Department of Biomedical Science, CHA University, Seongnam-si 13488, Korea; (S.P.); (J.Y.K.); (J.H.J.)
- Research Institute of Placental Science, CHA University, Seongnam-si 13488, Korea
| | - Gi Dae Kim
- Department of Food and Nutrition, Kyungnam University, Changwon-si 51767, Korea;
| | - Jae Yeon Kim
- Department of Biomedical Science, CHA University, Seongnam-si 13488, Korea; (S.P.); (J.Y.K.); (J.H.J.)
| | - Ji Hye Jun
- Department of Biomedical Science, CHA University, Seongnam-si 13488, Korea; (S.P.); (J.Y.K.); (J.H.J.)
- Research Institute of Placental Science, CHA University, Seongnam-si 13488, Korea
| | - Si Hyun Bae
- Department of Internal Medicine, Catholic University Medical College, Seoul 03312, Korea;
| | - Soon Koo Baik
- Department of Internal Medicine, Yonsei University Wonju College of Medicine, Wonju 26426, Korea;
| | - Seong-Gyu Hwang
- CHA Bundang Medical Center, Department of Internal Medicine, Division of Gastroenterology, CHA University School of Medicine, Seongnam-si 13496, Korea;
| | - Gi Jin Kim
- Department of Biomedical Science, CHA University, Seongnam-si 13488, Korea; (S.P.); (J.Y.K.); (J.H.J.)
- Research Institute of Placental Science, CHA University, Seongnam-si 13488, Korea
- Correspondence: ; Tel.: +82-31-881-7145
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Hardy S, Kostantin E, Hatzihristidis T, Zolotarov Y, Uetani N, Tremblay ML. Physiological and oncogenic roles of thePRLphosphatases. FEBS J 2018; 285:3886-3908. [DOI: 10.1111/febs.14503] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Revised: 04/30/2018] [Accepted: 05/09/2018] [Indexed: 12/13/2022]
Affiliation(s)
- Serge Hardy
- Rosalind and Morris Goodman Cancer Research Centre Montréal Canada
| | - Elie Kostantin
- Rosalind and Morris Goodman Cancer Research Centre Montréal Canada
- Department of Biochemistry McGill University Montréal Canada
| | - Teri Hatzihristidis
- Rosalind and Morris Goodman Cancer Research Centre Montréal Canada
- Department of Medicine Division of Experimental Medicine McGill University Montreal Canada
| | - Yevgen Zolotarov
- Rosalind and Morris Goodman Cancer Research Centre Montréal Canada
- Department of Biochemistry McGill University Montréal Canada
| | - Noriko Uetani
- Rosalind and Morris Goodman Cancer Research Centre Montréal Canada
| | - Michel L. Tremblay
- Rosalind and Morris Goodman Cancer Research Centre Montréal Canada
- Department of Biochemistry McGill University Montréal Canada
- Department of Medicine Division of Experimental Medicine McGill University Montreal Canada
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Al-Aidaroos AQO, Zeng Q. PRL-3 phosphatase and cancer metastasis. J Cell Biochem 2011; 111:1087-98. [PMID: 21053359 DOI: 10.1002/jcb.22913] [Citation(s) in RCA: 102] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The deregulated expression of members of the phosphatase of regenerating liver (PRL) family has been implicated in the metastatic progression of multiple human cancers. Importantly, PRL-1 and PRL-3 both possess the capacity to drive key steps in metastatic progression. Yet, little is known about the regulation and oncogenic mechanisms of this emerging class of dual-specificity phosphatases. This prospect article details the involvement of PRLs in the metastatic cascade, the regulatory mechanisms controlling PRL expression, and recent efforts in the characterization of PRL-modulated pathways and substrates using biochemical and high-throughput approaches. Current advances and future prospects in anti-cancer therapy targeting this family are also discussed.
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Affiliation(s)
- Abdul Qader O Al-Aidaroos
- Institute of Molecular and Cell Biology, A*STAR (Agency for Science, Technology and Research), 61 Biopolis Drive, Proteos, Singapore 138648, Republic of Singapore
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Abstract
Aberrant protein tyrosine phosphorylation resulting from the altered activity of protein tyrosine phosphatases (PTPs) is increasingly being implicated in the genesis and progression of human cancer. Accumulating evidence indicates that the dysregulated expression of members of the phosphatase of regenerating liver (PRL) subgroup of PTPs is linked to these processes. Enhanced expression of the PRLs, notably PRL-1 and PRL-3, promotes the acquisition of cellular properties that confer tumorigenic and metastatic abilities. Up-regulation of PRL-3 is associated with the progression and eventual metastasis of several types of human cancer. Indeed, PRL-3 shows promise as a biomarker and prognostic indicator in colorectal, breast, and gastric cancers. However, the substrates and molecular mechanisms of action of the PRLs have remained elusive. Recent findings indicate that PRLs may function in regulating cell adhesion structures to effect epithelial-mesenchymal transition. The identification of PRL substrates is key to understanding their roles in cancer progression and exploiting their potential as exciting new therapeutic targets for cancer treatment.
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Affiliation(s)
- Darrell C Bessette
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada
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Qian LP, Fan Y, Chen J, Lin GJ. Silence of PRL-3 gene by RNA interference in inhibiting the invasion of human colon cancer cells. Shijie Huaren Xiaohua Zazhi 2008; 16:767-770. [DOI: 10.11569/wcjd.v16.i7.767] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To investigate the effects of RNA interference-induced gene silence of proteins in regenerating liver cell-3 (PRL-3) on the invasion of human colon cancer cells.
METHODS: Colon cancer cell line HCT116 was transfected by PRL-3 small interfering RNA (siRNA), and the mRNA of PRL-3 was determined by fluorescence quantitative real-time polymerase chain reation (FRQ-PCR) assay. The anchorage-independent growth was examined using colony formation in soft agar, and invasion ability was evaluated by Boyden chamber model.
RESULTS: Compared with that in control groups, the level mRNA of PRL-3 in cancer cells transfected with PRL-3 siRNA was inhibited in a concentration- and time-dependent manner (P < 0.05). In vitro experiment showed that tranfection of colon cancer cells with PRL-3 siRNA resulted in a significant reduction of both colony formation and cell invasion in a concentration- and time-dependent manner, respectively (P < 0.05, P < 0.05). In vivo experiment showed that there were lots of cancer cells invading blood vessel and striped muscle around carcinoma tissue in two control groups, but such phenomenon did not occur in siRNA-transfected groups.
CONCLUSION: PRL-3 may play an important role in the invasion of human colon cancer cells, and RNAi-induced PRL-3 down-regulation can inhibit cell invasion ability.
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Yu L, Kelly U, Ebright JN, Malek G, Saloupis P, Rickman D, McKay BS, Arshavsky VY, Rickman CB. Oxidative stress-induced expression and modulation of Phosphatase of Regenerating Liver-1 (PRL-1) in mammalian retina. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2007; 1773:1473-82. [PMID: 17673310 PMCID: PMC2118714 DOI: 10.1016/j.bbamcr.2007.06.005] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2007] [Revised: 06/06/2007] [Accepted: 06/18/2007] [Indexed: 11/18/2022]
Abstract
The phosphatase of regenerating liver-1, PRL-1, gene was detected in a screen for foveal cone photoreceptor-associated genes. It encodes a small protein tyrosine phosphatase that was previously immunolocalized to the photoreceptors in primate retina. Here we report that in cones and cone-derived cultured cells both PRL-1 activity and PRL-1 gene expression are modulated under oxidative stress. Oxidation reversibly inhibited the phosphatase activity of PRL-1 due to the formation of an intramolecular disulfide bridge between Cys104 within the active site and another conserved Cys, Cys49. This modulation was observed in vitro, in cell culture and in isolated retinas exposed to hydrogen peroxide. The same treatment caused a rapid increase in PRL-1 expression levels in cultured cells which could be blocked by the protein translation inhibitor, cycloheximide. Increased PRL-1 expression was also observed in living rats subjected to constant light exposure inducing photooxidative stress. We further demonstrated that both oxidation and overexpression of PRL-1 upon oxidative stress are greatly enhanced by inhibition of the glutathione system responsible for cellular redox regulation. These findings suggest that PRL-1 is a molecular component of the photoreceptor's response to oxidative stress acting upstream of the glutathione system.
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Affiliation(s)
- Ling Yu
- Departments of Ophthalmology, Duke University Medical Center, Durham, NC 27710, USA
| | - Una Kelly
- Departments of Ophthalmology, Duke University Medical Center, Durham, NC 27710, USA
| | - Jessica N. Ebright
- Departments of Ophthalmology, Duke University Medical Center, Durham, NC 27710, USA
| | - Goldis Malek
- Departments of Ophthalmology, Duke University Medical Center, Durham, NC 27710, USA
| | - Peter Saloupis
- Departments of Ophthalmology, Duke University Medical Center, Durham, NC 27710, USA
| | - Dennis Rickman
- Departments of Ophthalmology, Duke University Medical Center, Durham, NC 27710, USA
- Department of Neurobiology, Duke University Medical Center, Durham, NC 27710, USA
| | - Brian S. McKay
- Departments of Ophthalmology and Cell Biology and Anatomy, University of Arizona, Tucson, AZ 85711, USA
| | - Vadim Y. Arshavsky
- Departments of Ophthalmology, Duke University Medical Center, Durham, NC 27710, USA
- Department of Neurobiology, Duke University Medical Center, Durham, NC 27710, USA
| | - Catherine Bowes Rickman
- Departments of Ophthalmology, Duke University Medical Center, Durham, NC 27710, USA
- Department of Cell Biology, Duke University Medical Center, Durham, NC 27710, USA
- Corresponding Author. Department of Ophthalmology, Duke University Medical Center, Albert Eye Research Institute Room 5010, Box 3802, Erwin Road, Durham, NC 27710, USA. Tel.: +1 (919) 668-0648; Fax: +1 (919) 684 3687. E-Mail: (Catherine Bowes Rickman, Ph.D.)
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Gnainsky Y, Spira G, Paizi M, Bruck R, Nagler A, Genina O, Taub R, Halevy O, Pines M. Involvement of the tyrosine phosphatase early gene of liver regeneration (PRL-1) in cell cycle and in liver regeneration and fibrosis effect of halofuginone. Cell Tissue Res 2006; 324:385-94. [PMID: 16508789 DOI: 10.1007/s00441-005-0092-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2005] [Accepted: 09/14/2005] [Indexed: 12/21/2022]
Abstract
Tyrosine phosphatase PRL-1 is one of the immediate-early genes up-regulated during liver regeneration and is apparently involved in cell proliferation. Previously, we have demonstrated that halofuginone, an inhibitor of collagen type I synthesis, prevents liver fibrosis and improves cirrhotic liver regeneration. In this study, we evaluated the effect of halofuginone on PRL-1 expression, its cellular localization in vitro and during liver regeneration, and fibrosis progression in vivo. In culture, halofuginone increased PRL-1 expression in primary rat hepatocytes and in hepatocellular carcinoma (HCC) cell lines, the former being more sensitive to halofuginone. The halofuginone-dependent increase in PRL-1 gene expression was correlated with an increase in the transcription factor early growth response-1 (Egr-1) and inversely correlated with the inhibition of cell proliferation. Halofuginone arrested HepG2 and Huh7 cell lines at the G1 phase, whereas Hep3B cells were arrested at G2/M, probably because of a reduction in the synthesis of cyclins D1 and B1 in all HCC cells and increased cyclin A in Hep3B cells. Halofuginone also affected the PRL-1 sub-cellular localization that was cell-cycle-dependent. In addition, halofuginone augmented PRL-1 expression in the remnant liver after partial hepatectomy and in chemically induced fibrosis in rats; this was accompanied by increased expression of insulin-like growth factor binding protein 1 (IGFBP-1), another immediate-early gene of regeneration. The regulation of the expression of the early genes of regeneration such as PRL-1 and IGFBP-1 is thus part of the mode of action of halofuginone and results in the prevention of liver fibrosis and improved cirrhotic liver regeneration.
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Affiliation(s)
- Yulia Gnainsky
- Institute of Animal sciences , Volcani Center , P.O. Box 6 , 50250 Bet Dagan , Israel
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Stephens BJ, Han H, Gokhale V, Von Hoff DD. PRL phosphatases as potential molecular targets in cancer. Mol Cancer Ther 2006; 4:1653-61. [PMID: 16275986 DOI: 10.1158/1535-7163.mct-05-0248] [Citation(s) in RCA: 119] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The phosphatase of regenerating liver (PRL) family of phosphatases, consisting of PRL-1, PRL-2, and PRL-3, represents an intriguing group of proteins being validated as biomarkers and therapeutic targets in cancer. Individual PRLs are overexpressed in a variety of cancer cell lines and tissues when compared with their normal counterparts. More importantly, several recent studies have shown that PRL-3 is expressed at higher levels and at a greater frequency in colorectal cancer metastases compared with primary colorectal tumors and normal colon tissue. Ectopic expression of PRLs in nontumorigenic cells can influence proliferation and the migratory and invasive properties of cells, while knockdown of endogenous PRL-3 or PRL-1 in cancerous cells using small interfering RNA can abrogate cell motility and ability to metastasize in a mouse model. However, the exact biological function and cellular substrates of the PRLs remain unclear. This review will discuss what is known about the PRLs, what makes the PRLs possible attractive targets for therapeutic intervention, and the possible future directions in PRL biology and inhibitor identification.
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Affiliation(s)
- Bret J Stephens
- Department of Molecular and Cellular Biology, University of Arizona, Tucson, USA
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Abd El-Aziz MM, Patel RJ, El-Ashry MF, Barragan I, Marcos I, Borrego S, Antiñolo G, Bhattacharya SS. Exclusion of Four Candidate Genes, KHDRBS2, PTP4A1, KIAA1411 and OGFRL1, as Causative of Autosomal Recessive Retinitis Pigmentosa. Ophthalmic Res 2005; 38:19-23. [PMID: 16192744 DOI: 10.1159/000088493] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2005] [Accepted: 05/26/2005] [Indexed: 11/19/2022]
Abstract
To identify the disease gene in 6 Spanish families with autosomal recessive retinitis pigmentosa linked to the RP25 locus, mutation screening of 4 candidate genes, KHDRBS2, PTP4A1, KIAA1411 and OGFRL1, was undertaken based on their expression or functional relevance to the retina. Twenty-six single nucleotide polymorphisms were identified, of which 14 were novel. Even though no pathological mutations were detected, these genes however remain as good candidates for other retinal degenerations mapping to the same chromosomal region.
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Affiliation(s)
- Mai M Abd El-Aziz
- Department of Molecular Genetics, Institute of Ophthalmology, London, UK.
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Meng F, Zolova O, Kokorina NA, Dobretsova A, Wight PA. Characterization of an intronic enhancer that regulates myelin proteolipid protein (Plp) gene expression in oligodendrocytes. J Neurosci Res 2005; 82:346-56. [PMID: 16155935 DOI: 10.1002/jnr.20640] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The myelin proteolipid protein (Plp) gene is expressed in oligodendrocytes and encodes the most abundant protein (approximately 50%) present in mature myelin from the central nervous system (CNS). Plp gene activity is low to nonexistent early in development but sharply increases, concurrently with the active myelination period of CNS development. Work from our laboratory suggests that the temporal regulation of Plp gene expression in mice is mediated by a positive regulatory element located within Plp intron 1 DNA. We have termed this regulatory element/region ASE (for antisilencer/enhancer). The ASE is situated approximately 1 kb downstream of exon 1 DNA and encompasses nearly 100 bp. To understand the mechanisms by which the ASE augments Plp gene expression in oligodendrocytes, Plp-lacZ constructs were generated and transfected into a mouse oligodendroglial cell line (N20.1). Results presented here demonstrate that upstream regulatory elements in the Plp promoter/5'-flanking DNA are not required for ASE activity; the ASE worked perfectly well when the thymidine kinase (TK) promoter was substituted for the Plp promoter. However, the relative location of the ASE appears to be important. When placed upstream of 2.4 kb of Plp 5'-flanking DNA, or downstream of the lacZ expression cassette, the ASE was no longer effective. Thus, the ASE might have to be in the context of the intron in order to function. To begin to identify the crucial nucleotides within the ASE, orthologous sequences from rat, human, cow, and pig Plp genes were swapped for the mouse sequence. Results presented here demonstrate that the orthologous sequence from rat can substitute for the mouse ASE, unlike those from human, cow, or pig.
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Affiliation(s)
- Fanxue Meng
- Department of Physiology and Biophysics, University of Arkansas for Medical Sciences, Little Rock, Arkansas 72205, USA
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Russo J, Russo IH. Development of the human breast. Maturitas 2004; 49:2-15. [PMID: 15351091 DOI: 10.1016/j.maturitas.2004.04.011] [Citation(s) in RCA: 160] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2003] [Revised: 04/07/2004] [Accepted: 04/19/2004] [Indexed: 10/26/2022]
Abstract
The human breast undergoes a complete series of changes from intrauterine life to senescence. These changes can be divided into two distinct phases; the developmental phase and the differentiation phase. The developmental phase includes the early stages of gland morphogenesis, from nipple epithelium to lobule formation. In lobule formation, both processes, development and differentiation, take place almost simultaneously. For example, the progressive transition of lobule type 1 to types 2, 3, and 4 requires active cell proliferation, to acquire the cell mass necessary for the function of milk secretion. This later process implies differentiation of the mammary epithelium. Therefore, the presence of lobule type 4 is the maximal expression of development and differentiation in the adult gland, whereas the presence of lobule type 3 could indicate that the gland has already been developed. It is important to point out that the presence of proteins that are indicative of milk secretion, such as alpha-lactalbumin, casein, or milk fat lobule type membrane protein, also indicates cellular differentiation of breast epithelium. However, only when all the other components of milk, (such as lactose, alpha-lactalbumin, casein and milk fat) are coordinately synthesized within the appropriate structure can full differentiation of the mammary gland be acknowledged.
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Affiliation(s)
- Jose Russo
- Breast Cancer Research Laboratory, Fox Chase Cancer Center, 7701 Burholme Avenue, Philadelphia, PA 19111, USA.
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Werner SR, Lee PA, DeCamp MW, Crowell DN, Randall SK, Crowell PL. Enhanced cell cycle progression and down regulation of p21(Cip1/Waf1) by PRL tyrosine phosphatases. Cancer Lett 2004; 202:201-11. [PMID: 14643450 DOI: 10.1016/s0304-3835(03)00517-2] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Human PRL-1, PRL-2, and PRL-3 tyrosine phosphatases induce the malignant transformation of epithelial cells. We tested the hypothesis that the oncogenic effects of PRL occur by increasing cellular proliferation. Cells stably transfected with PRL-1 or PRL-2 exhibited 2.7-3.3-fold increases over control cells in the rate of DNA synthesis and the proportion of cells in S-phase, and they progressed more rapidly from G1 into S. In addition, cells overexpressing either PRL-1 or PRL-2 exhibited enhanced cyclin-dependent kinase 2 (CDK2) activity and significantly lower p21(Cip1/Waf1) protein levels, and PRL-1 overexpressing cells had higher cyclin A protein levels than control cells. We conclude that PRL phosphatases increase cell proliferation by stimulating progression from G1 into S phase, and this process may be dependent on the down regulation of the cyclin dependent kinase inhibitor p21(Cip1/Waf1).
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Affiliation(s)
- Sean R Werner
- Department of Biology, Indiana University-Purdue University Indianapolis, Indianapolis, IN 46202-5132, USA
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15
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Mu JS, Liu Y, Wang G, Cheng J, Duan HJ, Li K, Lu YY, Wang L, Wang HF. Cloning of genes transactivated by NS3 protein of HCV with suppressive and subtractive hybridization. Shijie Huaren Xiaohua Zazhi 2003; 11:399-403. [DOI: 10.11569/wcjd.v11.i4.399] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM To construct a subtractive cDNA library of genes transactivated by NS3 protein of hepatitis C virus (HCV) with suppressive and subtractive hybridization technique and clone genes associated with transactivation.
METHODS The mRNA was isolated from HepG2 cells transfected with pcDNA3.1(-)-NS3, and pcDNA3.1(-) empty vector, respectively; cDNA was synthesized. After digestion with restriction enzyme RsaI, cDNA fragments were obtained by restriction enzyme RsaI digestion. Tester cDNA was then divided into two groups and ligated to the specific adaptor 1 and adaptor 2, respectively. After tester cDNA was hybridized with driver cDNA twice and underwent two times of nested PCR, amplified cDNA fragments were subcloned into T/A plasmid vectors to set up the subtractive library. Amplification of the library was carried out with E. coli strain JM109. The cDNA was sequenced and analyzed in GenBank with Blast search after PCR.
RESULTS The amplified library contained 70 positive clones. Results of PCR study indicated that 56 clones had inserts of 200-1 000 bp in length. Sequence analysis suggested that six novel cDNA sequences might be target genes transactivated by NS3 protein.
CONCLUSION The subtractive library of genes transactivated by NS3 protein of HCV was constructed successfully.
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Affiliation(s)
- Jin-Song Mu
- Gene Therapy Research Center, Institute of Infectious Diseases, The 302 Hospital of PLA, Beijing 100039, P.R.China
| | - Yan Liu
- Gene Therapy Research Center, Institute of Infectious Diseases, The 302 Hospital of PLA, Beijing 100039, P.R.China
| | - Gang Wang
- Gene Therapy Research Center, Institute of Infectious Diseases, The 302 Hospital of PLA, Beijing 100039, P.R.China
| | - Jun Cheng
- Gene Therapy Research Center, Institute of Infectious Diseases, The 302 Hospital of PLA, Beijing 100039, P.R.China
| | - Hui-Juan Duan
- Gene Therapy Research Center, Institute of Infectious Diseases, The 302 Hospital of PLA, Beijing 100039, P.R.China
| | - Ke Li
- Gene Therapy Research Center, Institute of Infectious Diseases, The 302 Hospital of PLA, Beijing 100039, P.R.China
| | - Yin-Ying Lu
- Gene Therapy Research Center, Institute of Infectious Diseases, The 302 Hospital of PLA, Beijing 100039, P.R.China
| | - Lin Wang
- Gene Therapy Research Center, Institute of Infectious Diseases, The 302 Hospital of PLA, Beijing 100039, P.R.China
| | - Hui-Fen Wang
- Gene Therapy Research Center, Institute of Infectious Diseases, The 302 Hospital of PLA, Beijing 100039, P.R.China
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16
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Fedorova L, Fedorov A. Introns in gene evolution. CONTEMPORARY ISSUES IN GENETICS AND EVOLUTION 2003. [DOI: 10.1007/978-94-010-0229-5_3] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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Wang J, Kirby CE, Herbst R. The tyrosine phosphatase PRL-1 localizes to the endoplasmic reticulum and the mitotic spindle and is required for normal mitosis. J Biol Chem 2002; 277:46659-68. [PMID: 12235145 DOI: 10.1074/jbc.m206407200] [Citation(s) in RCA: 92] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
PRL-1 is one of three closely related protein-tyrosine phosphatases, which are characterized by C-terminal farnesylation. Recent reports suggest that they are involved in the regulation of cell proliferation and transformation. However, their biological function has not yet been determined. Here we show that PRL-1 mRNA is overexpressed in a number of human tumor cell lines, including HeLa cells. Using immunofluorescence we studied the subcellular localization of endogenous PRL-1, and our results demonstrate that PRL-1 exhibits cell cycle-dependent localization; in non-mitotic HeLa cells, PRL-1 is localized to the endoplasmic reticulum in a farnesylation-dependent manner. In mitotic cells PRL-1 relocalizes to the centrosomes and the spindle apparatus, proximal to the centrosomes, in a farnesylation-independent manner. Conditional expression of a catalytic domain mutant in HeLa cells results in a delay in the progression of cells through mitosis but has no effect on other phases of the cell cycle. Further, expression of a farnesylation site PRL-1 mutant results in mitotic defects, characterized by chromosomal bridges in anaphase and lagging chromosomes, without affecting spindle checkpoint function. Together, these results suggest that PRL-1 function is regulated in a cell cycle-dependent manner and implicate PRL-1 in regulating progression through mitosis, possibly by modulating spindle dynamics.
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Affiliation(s)
- Jing Wang
- DNAX Research Institute, Palo Alto, California 94304, USA
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18
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Mueller L, Broering DC, Meyer J, Vashist Y, Goettsche J, Wilms C, Rogiers X. The induction of the immediate-early-genes Egr-1, PAI-1 and PRL-1 during liver regeneration in surgical models is related to increased portal flow. J Hepatol 2002; 37:606-12. [PMID: 12399226 DOI: 10.1016/s0168-8278(02)00238-6] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
BACKGROUND The environmental triggers which control liver regeneration following partial hepatectomy (PH) are not clear. With respect to haemodynamic changes, the model of rat portal branch ligation (PBL) provides the unique opportunity to discriminate transcriptional events, which selectively result from increased portal flow. AIMS The potential role of portal over-flow on early expression of early growth response gene-1 (Egr-1), type-1 plasminogen activator inhibitor (PAI-1) and phosphatase of regenerating liver-1 (PRL-1) was analysed by a comparative experimental study using PBL and PH. METHODS Operative procedures were carried out in male Wistar rats. Growth kinetics were measured by liver weight indices. S-phase-specific mRNA-levels of H2B-histone protein (H2B), as well as expression analysis of Egr-1, PAI-1 and PRL-1 were examined by Northern blot experiments. RESULTS Growth patterns did not differ significantly between PBL and PH, whereas peak H2B expression occurred earlier after PH. Egr-1 and PAI-1 were specifically induced during the first few hours in the hyper-perfused lobes following PBL and PH. PRL-1-expression selectively peaked 3h after PH and PBL in the hyper-perfused lobes. CONCLUSIONS Increased portal flow after PBL and PH was associated with induction of Egr-1, PAI-1 and PRL-1. Thus, haemodynamic changes affect the molecular immediate-early response during liver regeneration.
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Affiliation(s)
- Lars Mueller
- Department of Hepato-biliary Surgery, University Hospital Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany.
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19
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Wang Q, Holmes DIR, Powell SM, Lu QL, Waxman J. Analysis of stromal-epithelial interactions in prostate cancer identifies PTPCAAX2 as a potential oncogene. Cancer Lett 2002; 175:63-9. [PMID: 11734337 DOI: 10.1016/s0304-3835(01)00703-0] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A PCR-based subtractive hybridisation technique was used to identify genes involved in stromal-epithelial interactions in prostate cancer. Eight genes were identified as being differentially expressed in benign prostatic fibroblast cells after stimulation with tumourigenic LNCaP conditioned media. One of these genes, protein tyrosine phosphatase CAAX2 (PTPCAAX2; also described as PTP4A and OV-1), has recently been shown to be oncogenic in hamster pancreatic epithelial cells. We show that PTPCAAX2 expression is up-regulated 4-fold in benign prostatic fibroblast cells 24 h after stimulation with LNCaP conditioned media and up-regulated 9-fold in prostatic tumour fibroblast cells. PTPCAAX2 overexpression was also detected in both androgen-dependent and androgen-independent prostate cancer cell lines and prostate tumour tissue, as determined by RT-PCR analysis and in situ hybridisation. These observations of PTPCAAX2 overexpression in prostate tumour cells and tissue suggest that PTPCAAX2 may potentially function as an oncogene in prostate cancer.
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Affiliation(s)
- Qin Wang
- Department of Cancer Cell Biology, Imperial College School of Medicine, Hammersmith Campus, Du Cane Road, W12 ONN, London, UK
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20
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Matter WF, Estridge T, Zhang C, Belagaje R, Stancato L, Dixon J, Johnson B, Bloem L, Pickard T, Donaghue M, Acton S, Jeyaseelan R, Kadambi V, Vlahos CJ. Role of PRL-3, a human muscle-specific tyrosine phosphatase, in angiotensin-II signaling. Biochem Biophys Res Commun 2001; 283:1061-8. [PMID: 11355880 DOI: 10.1006/bbrc.2001.4881] [Citation(s) in RCA: 103] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Action of protein kinases and phosphatases contributes to myocardial hypertrophy. PRL-3, a protein tyrosine phosphatase, was identified in a cDNA library from an explanted human heart obtained from a patient with idiopathic cardiomyopathy. PRL-3 is expressed in heart and skeletal muscle, exhibiting approximately 76% identity to the ubiquitous tyrosine phosphatase PRL-1, which was reported to increase cell proliferation. PRL-3 was cloned into E. coli and purified using affinity chromatography. PRL-3 activity was determined using the substrate 6,8-difluoro-4-methylumbelliferyl phosphate, and was inhibited by vanadate and analogs. HEK293 cells expressing PRL-3 demonstrated increased growth rates versus nontransfected cells or cells transfected with the catalytically inactive C104S PRL-3 mutant. The tyrosine phosphatase inhibitor, potassium bisperoxo (bipyridine) oxovanadate V, normalizes the growth rate of PRL-3 expressing cells to that of parental HEK293 cells in a concentration-dependent manner. Using FLIPR analysis, parental HEK293 cells mobilize calcium when stimulated with angiotensin-II (AngII). However, calcium mobilization is inhibited in cells expressing wild-type PRL-3 when stimulated with AngII, while cells expressing the inactive mutant of PRL-3 mobilize calcium to the same extent as parental HEK293 cells. Western blots comparing PRL-3 transfected cells to parental HEK293 cells showed dephosphorylation of p130(cas) in response to AngII. These data suggest a role for PRL-3 in the modulation of intracellular calcium transients induced by AngII.
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Affiliation(s)
- W F Matter
- Cardiovascular Research, Eli Lilly and Company, Indianapolis, Indiana 46285, USA
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21
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Poetsch M, Dittberner T, Woenckhaus C. PTEN/MMAC1 in malignant melanoma and its importance for tumor progression. CANCER GENETICS AND CYTOGENETICS 2001; 125:21-6. [PMID: 11297763 DOI: 10.1016/s0165-4608(00)00353-8] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
A novel tumor suppressor gene, PTEN/MMAC1, on 10q23, displayed a number of mutations in solid tumors as gliomas and breast cancer. Aberrations of the long arm of chromosome 10 have been frequently detected in tumor progression of malignant melanoma of the skin by a variety of methods including cytogenetic analysis, fluorescence in situ hybridization and loss of heterozygosity analysis. Compared to previous studies, which propose an involvement of PTEN/MMAC1 in malignant melanoma mostly on the basis of data derived from cell lines and metastases, we analyzed a broader spectrum of exclusively patient derived tumor tissue by PCR and direct sequencing analysis of PTEN/MMAC1. Here, we present data of 25 primary melanomas (8 superficial spreading melanomas, 17 nodular melanomas) and 25 metastases of 41 patients. Neither loss of the complete gene nor a whole exon nor any nonsense mutations could be demonstrated. However, we detected several polymorphisms and some mutations in the introns, and in two metastatic tumors mutations with an amino acid change. Our results obtained from tissue samples underline that mutations of PTEN/MMAC1 are not an essential event in the onset of malignant melanoma of the skin, but could have an impact on tumor progression.
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Affiliation(s)
- M Poetsch
- Institute of Forensic Medicine, Ernst Moritz Arndt-University, Kuhstrasse 30, D-17489, Greifswald, Germany.
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22
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Leu JI, Crissey MA, Leu JP, Ciliberto G, Taub R. Interleukin-6-induced STAT3 and AP-1 amplify hepatocyte nuclear factor 1-mediated transactivation of hepatic genes, an adaptive response to liver injury. Mol Cell Biol 2001; 21:414-24. [PMID: 11134330 PMCID: PMC86585 DOI: 10.1128/mcb.21.2.414-424.2001] [Citation(s) in RCA: 284] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Following hepatic injury or stress, gluconeogenic and acute-phase response genes are rapidly upregulated to restore metabolic homeostasis and limit tissue damage. Regulation of the liver-restricted insulin-like growth factor binding protein 1 (IGFBP-1) gene is dramatically altered by changes in the metabolic state and hepatectomy, and thus it provided an appropriate reporter to assess the transcriptional milieu in the liver during repair and regeneration. The cytokine interleukin-6 (IL-6) is required for liver regeneration and repair, and it transcriptionally upregulates a vast array of genes during liver growth by unknown mechanisms. Evidence for a biologic role of IL-6 in IGFBP-1 upregulation was demonstrated by increased expression of hepatic IGFBP-1 in IL-6 transgenic and following injection of IL-6 into nonfasting animals and its reduced expression in IL-6(-/-) livers posthepatectomy. In both hepatic and nonhepatic cells, IL-6 -mediated IGFBP-1 promoter activation was via an intact hepatocyte nuclear factor 1 (HNF-1) site and was dependent on the presence of endogenous liver factor HNF-1 and induced factors STAT3 and AP-1 (c-Fos/c-Jun). IL-6 acted through the STAT3 pathway, as dominant negative STAT3 completely blocked IL-6-mediated stimulation of the IGFBP-1 promoter via the HNF-1 site. HNF-1/c-Fos and HNF-1/STAT3 protein complexes were detected in mouse livers and in hepatic and nonhepatic cell lines overexpressing STAT3/c-Fos/HNF-1. Similar regulation was demonstrated using glucose-6-phosphatase and alpha-fibrinogen promoters, indicating that HNF-1/IL-6/STAT3/AP-1-mediated transactivation of hepatic gene expression is a general phenomenon after liver injury. These results demonstrate that the two classes of transcription factors, growth induced (STAT3 and AP-1) and tissue specific (HNF-1), can interact as an adaptive response to liver injury to amplify expression of hepatic genes important for the homeostatic response during organ repair.
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Affiliation(s)
- J I Leu
- Department of Genetics, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104, USA
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23
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Yarovinsky TO, Rickman DW, Diamond RH, Taub R, Hageman GS, Bowes Rickman C. Expression of the protein tyrosine phosphatase, phosphatase of regenerating liver 1, in the outer segments of primate cone photoreceptors. BRAIN RESEARCH. MOLECULAR BRAIN RESEARCH 2000; 77:95-103. [PMID: 10814835 DOI: 10.1016/s0169-328x(00)00045-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Foveal cone photoreceptors are morphologically distinct and, presumably, express unique transcripts. We have identified a cDNA clone encoding the protein tyrosine phosphatase (PTP), phosphatase of regenerating liver 1 (PRL-1) in a screen for genes that are enriched in monkey fovea. PRL-1 was originally isolated as an immediate early gene in regenerating liver [R.H. Diamond, D.E. Cressman, T.M. Laz, C.S. Abrams, R. Taub, PRL-1, a unique nuclear protein tyrosine phosphatase, affects cell growth, Mol. Cell Biol. 14 (1994) 3752-3762]. On cDNA Southern blots of human and monkey retina, radiolabeled PRL-1 cDNA hybridized to a single mRNA species of about 2.5 kb that was most intense in fovea-enriched samples. The monkey PRL-1 deduced amino acid sequence is identical to human, rat and mouse PRL-1. Affinity-purified antibodies directed against PRL-1 preferentially labeled cone photoreceptor cells and a subpopulation of bipolar cells in monkey retina. Immunoreactivity in cones was confined to red and green, but not to blue, cones and was restricted to the outer segments. Immunolocalization also revealed that PRL-1 protein expression was non-nuclear, suggesting that its function in the retina may be unrelated to its role in other tissues where it is expressed primarily in nuclei. Although both foveal and extrafoveal cones were PRL-1 reactive, the high abundance of PRL-1 mRNAs detected in monkey fovea correlates with the high concentration of cones in the fovea. The PRL-1 gene is located on chromosome 6q within an interval that also contains the genes that cause two hereditary retinal dystrophies. These studies demonstrate novel expression of the PRL-1 gene in the neural retina and suggest the phosphatase activity of PRL-1 may modulate normal cone photoreceptor cell function.
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Affiliation(s)
- T O Yarovinsky
- Department of Ophthalmology and Visual Sciences, University of Iowa College of Medicine, 200 Hawkins Blvd., Iowa City, IA, USA
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24
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Peng Y, Du K, Ramirez S, Diamond RH, Taub R. Mitogenic up-regulation of the PRL-1 protein-tyrosine phosphatase gene by Egr-1. Egr-1 activation is an early event in liver regeneration. J Biol Chem 1999; 274:4513-20. [PMID: 9988683 DOI: 10.1074/jbc.274.8.4513] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The cellular signals that initiate cell growth are incompletely understood. Insight could be provided by understanding the signals regulating the transcriptional induction of immediate-early genes which occurs within minutes of the growth stimulus. The expression of the PRL-1 gene, which encodes a unique nuclear protein-tyrosine phosphatase, is rapidly induced in regenerating liver and mitogen-treated cells. Transcription of the PRL-1 gene increased in the rat liver remnant within a few minutes after partial hepatectomy and largely explained the increase in steady-state PRL-1 mRNA in the first few hours posthepatectomy. Egr-1 (early growth response factor) specifically bound a region of the proximal PRL-1 promoter P1 (-99). Egr-1 binding activity was more rapidly induced in regenerating liver than mitogen-treated H35 and NIH 3T3 cells, remained elevated through 4 h posthepatectomy, and appeared to be dependent not only on new Egr-1 protein synthesis but on post-translational regulation of Egr-1. Egr-1 efficiently transactivated a PRL-1 promoter reporter construct containing an intact not mutant Egr-1 site, and the Egr-1 site largely accounted for PRL-1 gene up-regulation in response to mitogen stimulation. These data predict that Egr-1 activation is an early event in liver regeneration and mitogen-activated cells that provides a regulatory stimulus for a subset of immediate-early genes.
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Affiliation(s)
- Y Peng
- Department of Genetics, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104, USA
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25
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Du K, Leu JI, Peng Y, Taub R. Transcriptional up-regulation of the delayed early gene HRS/SRp40 during liver regeneration. Interactions among YY1, GA-binding proteins, and mitogenic signals. J Biol Chem 1998; 273:35208-15. [PMID: 9857059 DOI: 10.1074/jbc.273.52.35208] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Arg-Ser-rich domain-containing proteins (SR proteins), a family of splicing factors, can regulate pre-mRNA alternative splicing in a concentration dependent manner. Thus, the relative expression of various SR proteins may play an important role in alternative splicing regulation. HRS/SRp40, an SR protein and delayed early gene in liver regeneration, can mediate alternative splicing of fibronectin mRNA. Here we determined that transcription of the HRS/SRp40 gene is induced about 5-fold during liver regeneration, similar to the level of steady-state mRNA. We found that both mouse and human HRS promoters lack TATA and CAAT boxes. The mouse promoter region from -130 to -18, which contains highly conserved GA-binding protein (GABP) and YY1 binding sites, conferred high transcriptional activity. While GABPalpha/GABPbeta heterodimer transactivated the HRS promoter, YY1 functioned as a repressor. During liver regeneration, the relative amount of GABPalpha/GABPbeta heterodimer increased 3-fold, and YY1 changed little, which could partially account for the increase in HRS gene transcription. Interleukin-6, a critical mitogenic component of liver regeneration, was able to relieve the repressive activity of the YY1 site within the HRS promoter. The combined effect of small changes in the level of existing transcription factors and mitogenic signals may explain the transcriptional activation of the HRS gene during cell growth.
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Affiliation(s)
- K Du
- Department of Genetics, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104, USA
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