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Song S, Honjo S, Jin J, Chang SS, Scott AW, Chen Q, Kalhor N, Correa AM, Hofstetter WL, Albarracin CT, Wu TT, Johnson RL, Hung MC, Ajani JA. The Hippo Coactivator YAP1 Mediates EGFR Overexpression and Confers Chemoresistance in Esophageal Cancer. Clin Cancer Res 2015; 21:2580-90. [PMID: 25739674 DOI: 10.1158/1078-0432.ccr-14-2191] [Citation(s) in RCA: 185] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2014] [Accepted: 02/13/2015] [Indexed: 01/12/2023]
Abstract
PURPOSE Esophageal cancer is an aggressive malignancy and often resistant to therapy. Overexpression of EGFR has been associated with poor prognosis of patients with esophageal cancer. However, clinical trials using EGFR inhibitors have not provided benefit for patients with esophageal cancer. Failure of EGFR inhibition may be due to crosstalk with other oncogenic pathways. EXPERIMENTAL DESIGN In this study, expression of YAP1 and EGFR were examined in EAC-resistant tumor tissues versus sensitive tissues by IHC. Western blot analysis, immunofluorescence, real-time PCR, promoter analysis, site-directed mutagenesis, and in vitro and in vivo functional assays were performed to elucidate the YAP1-mediated EGFR expression and transcription and the relationship with chemoresistance in esophageal cancer. RESULTS We demonstrate that Hippo pathway coactivator YAP1 can induce EGFR expression and transcription in multiple cell systems. Both YAP1 and EGFR are overexpressed in resistant esophageal cancer tissues compared with sensitive esophageal cancer tissues. Furthermore, we found that YAP1 increases EGFR expression at the level of transcription requiring an intact TEAD-binding site in the EGFR promoter. Most importantly, exogenous induction of YAP1 induces resistance to 5-fluorouracil and docetaxcel, whereas knockdown of YAP1 sensitizes esophageal cancer cells to these cytotoxics. Verteporfin, a YAP1 inhibitor, effectively inhibits both YAP1 and EGFR expression and sensitizes cells to cytotoxics. CONCLUSIONS Our data provide evidence that YAP1 upregulation of EGFR plays an important role in conferring therapy resistance in esophageal cancer cells. Targeting YAP1-EGFR axis may be more efficacious than targeting EGFR alone in esophageal cancer.
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Affiliation(s)
- Shumei Song
- Department of Gastrointestinal Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas.
| | - Soichiro Honjo
- Department of Gastrointestinal Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Jiankang Jin
- Department of Gastrointestinal Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Shih-Shin Chang
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Ailing W Scott
- Department of Gastrointestinal Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Qiongrong Chen
- Department of Gastrointestinal Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Neda Kalhor
- Department of Pathology, MD Anderson Cancer Center, The University of Texas, Houston, Texas
| | - Arlene M Correa
- Department of Thoracic and Cardiovascular Surgery, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Wayne L Hofstetter
- Department of Thoracic and Cardiovascular Surgery, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Constance T Albarracin
- Department of Pathology, MD Anderson Cancer Center, The University of Texas, Houston, Texas
| | - Tsung-Teh Wu
- Department of Pathology, Mayo Clinic, Rochester, Minnesota
| | - Randy L Johnson
- Department of Biochemistry and Molecular Biology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Mien-Chie Hung
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas. Center for Molecular Medicine and Graduate Institute of Cancer Biology, China Medical University, Taichung, Taiwan
| | - Jaffer A Ajani
- Department of Gastrointestinal Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas.
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Leung WH, Vong QP, Lin W, Bouck D, Wendt S, Sullivan E, Li Y, Bari R, Chen T, Leung W. PRL-3 mediates the protein maturation of ULBP2 by regulating the tyrosine phosphorylation of HSP60. THE JOURNAL OF IMMUNOLOGY 2015; 194:2930-41. [PMID: 25687758 DOI: 10.4049/jimmunol.1400817] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Many malignant cells release the NKG2D ligand ULBP2 from their cell surface to evade immunosurveillance by NK cells and CD8 T cells. Although the shedding mechanism remains unclear, various inhibitors of matrix metalloproteinases have been shown to efficiently block the release of soluble ULBP2. The clinical use of these inhibitors, however, is limited because of adverse side effects. Using high-throughput screening technique, we identified a specific inhibitor of phosphatase of regenerating liver 3 (PRL-3) that could reduce the level of soluble ULBP2 in the culture supernatant of various cancer cell lines. Inhibition or gene knockdown of PRL-3 did not reduce ULBP2 shedding, but rather suppressed posttranslational maturation of ULBP2, resulting in intracellular retention of immature ULBP2. We then found that ULBP2 was constitutively associated with heat shock protein HSP60. Complete maturation of ULBP2 required tyrosine phosphorylation of HSP60 which was mediated by PRL-3.
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Affiliation(s)
- Wai-Hang Leung
- Department of Bone Marrow Transplantation and Cellular Therapy, St. Jude Children's Research Hospital, Memphis, TN 38105
| | - Queenie P Vong
- Department of Bone Marrow Transplantation and Cellular Therapy, St. Jude Children's Research Hospital, Memphis, TN 38105
| | - Wenwei Lin
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, TN 38105; and
| | - David Bouck
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, TN 38105; and
| | - Susanne Wendt
- Department of Bone Marrow Transplantation and Cellular Therapy, St. Jude Children's Research Hospital, Memphis, TN 38105
| | - Erin Sullivan
- Department of Bone Marrow Transplantation and Cellular Therapy, St. Jude Children's Research Hospital, Memphis, TN 38105
| | - Ying Li
- Department of Bone Marrow Transplantation and Cellular Therapy, St. Jude Children's Research Hospital, Memphis, TN 38105
| | - Rafijul Bari
- Department of Bone Marrow Transplantation and Cellular Therapy, St. Jude Children's Research Hospital, Memphis, TN 38105
| | - Taosheng Chen
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, TN 38105; and
| | - Wing Leung
- Department of Bone Marrow Transplantation and Cellular Therapy, St. Jude Children's Research Hospital, Memphis, TN 38105; Department of Pediatrics, University of Tennessee Health Science Center, Memphis, TN 38103
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He RJ, Yu ZH, Zhang RY, Zhang ZY. Protein tyrosine phosphatases as potential therapeutic targets. Acta Pharmacol Sin 2014; 35:1227-46. [PMID: 25220640 DOI: 10.1038/aps.2014.80] [Citation(s) in RCA: 246] [Impact Index Per Article: 24.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2014] [Accepted: 07/31/2014] [Indexed: 12/17/2022] Open
Abstract
Protein tyrosine phosphorylation is a key regulatory process in virtually all aspects of cellular functions. Dysregulation of protein tyrosine phosphorylation is a major cause of human diseases, such as cancers, diabetes, autoimmune disorders, and neurological diseases. Indeed, protein tyrosine phosphorylation-mediated signaling events offer ample therapeutic targets, and drug discovery efforts to date have brought over two dozen kinase inhibitors to the clinic. Accordingly, protein tyrosine phosphatases (PTPs) are considered next-generation drug targets. For instance, PTP1B is a well-known targets of type 2 diabetes and obesity, and recent studies indicate that it is also a promising target for breast cancer. SHP2 is a bona-fide oncoprotein, mutations of which cause juvenile myelomonocytic leukemia, acute myeloid leukemia, and solid tumors. In addition, LYP is strongly associated with type 1 diabetes and many other autoimmune diseases. This review summarizes recent findings on several highly recognized PTP family drug targets, including PTP1B, Src homology phosphotyrosyl phosphatase 2(SHP2), lymphoid-specific tyrosine phosphatase (LYP), CD45, Fas associated phosphatase-1 (FAP-1), striatal enriched tyrosine phosphatases (STEP), mitogen-activated protein kinase/dual-specificity phosphatase 1 (MKP-1), phosphatases of regenerating liver-1 (PRL), low molecular weight PTPs (LMWPTP), and CDC25. Given that there are over 100 family members, we hope this review will serve as a road map for innovative drug discovery targeting PTPs.
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de Jong PR, Takahashi N, Harris AR, Lee J, Bertin S, Jeffries J, Jung M, Duong J, Triano AI, Lee J, Niv Y, Herdman DS, Taniguchi K, Kim CW, Dong H, Eckmann L, Stanford SM, Bottini N, Corr M, Raz E. Ion channel TRPV1-dependent activation of PTP1B suppresses EGFR-associated intestinal tumorigenesis. J Clin Invest 2014; 124:3793-806. [PMID: 25083990 DOI: 10.1172/jci72340] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2013] [Accepted: 06/06/2014] [Indexed: 12/12/2022] Open
Abstract
The intestinal epithelium has a high rate of turnover, and dysregulation of pathways that regulate regeneration can lead to tumor development; however, the negative regulators of oncogenic events in the intestinal epithelium are not fully understood. Here we identified a feedback loop between the epidermal growth factor receptor (EGFR), a known mediator of proliferation, and the transient receptor potential cation channel, subfamily V, member 1 (TRPV1), in intestinal epithelial cells (IECs). We found that TRPV1 was expressed by IECs and was intrinsically activated upon EGFR stimulation. Subsequently, TRPV1 activation inhibited EGFR-induced epithelial cell proliferation via activation of Ca2+/calpain and resulting activation of protein tyrosine phosphatase 1B (PTP1B). In a murine model of multiple intestinal neoplasia (Apc(Min/+) mice), TRPV1 deficiency increased adenoma formation, and treatment of these animals with an EGFR kinase inhibitor reversed protumorigenic phenotypes, supporting a functional association between TRPV1 and EGFR signaling in IECs. Administration of a TRPV1 agonist suppressed intestinal tumorigenesis in Apc(Min/+) mice, similar to--as well as in conjunction with--a cyclooxygenase-2 (COX-2) inhibitor, which suggests that targeting both TRPV1 and COX-2 has potential as a therapeutic approach for tumor prevention. Our findings implicate TRPV1 as a regulator of growth factor signaling in the intestinal epithelium through activation of PTP1B and subsequent suppression of intestinal tumorigenesis.
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Huang YH, Al-Aidaroos AQO, Yuen HF, Zhang SD, Shen HM, Rozycka E, McCrudden CM, Tergaonkar V, Gupta A, Lin YB, Thiery JP, Murray JT, Zeng Q. A role of autophagy in PTP4A3-driven cancer progression. Autophagy 2014; 10:1787-800. [PMID: 25136802 DOI: 10.4161/auto.29989] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Autophagy, a "self-eating" cellular process, has dual roles in promoting and suppressing tumor growth, depending on cellular context. PTP4A3/PRL-3, a plasma membrane and endosomal phosphatase, promotes multiple oncogenic processes including cell proliferation, invasion, and cancer metastasis. In this study, we demonstrate that PTP4A3 accumulates in autophagosomes upon inhibition of autophagic degradation. Expression of PTP4A3 enhances PIK3C3-BECN1-dependent autophagosome formation and accelerates LC3-I to LC3-II conversion in an ATG5-dependent manner. PTP4A3 overexpression also enhances the degradation of SQSTM1, a key autophagy substrate. These functions of PTP4A3 are dependent on its catalytic activity and prenylation-dependent membrane association. These results suggest that PTP4A3 functions to promote canonical autophagy flux. Unexpectedly, following autophagy activation, PTP4A3 serves as a novel autophagic substrate, thereby establishing a negative feedback-loop that may be required to fine-tune autophagy activity. Functionally, PTP4A3 utilizes the autophagy pathway to promote cell growth, concomitant with the activation of AKT. Clinically, from the largest ovarian cancer data set (GSE 9899, n = 285) available in GEO, high levels of expression of both PTP4A3 and autophagy genes significantly predict poor prognosis of ovarian cancer patients. These studies reveal a critical role of autophagy in PTP4A3-driven cancer progression, suggesting that autophagy could be a potential Achilles heel to block PTP4A3-mediated tumor progression in stratified patients with high expression of both PTP4A3 and autophagy genes.
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Affiliation(s)
- Yu-Han Huang
- Institute of Molecular and Cell Biology; A*STAR (Agency for Science, Technology and Research); Singapore; NUS Graduate School for Integrative Sciences and Engineering; National University of Singapore; Singapore
| | - Abdul Qader O Al-Aidaroos
- Institute of Molecular and Cell Biology; A*STAR (Agency for Science, Technology and Research); Singapore
| | - Hiu-Fung Yuen
- Institute of Molecular and Cell Biology; A*STAR (Agency for Science, Technology and Research); Singapore
| | - Shu-Dong Zhang
- Center for Cancer Research and Cell Biology; Queen's University Belfast; Belfast UK
| | - Han-Ming Shen
- Department of Epidemiology and Public Health; National University of Singapore; Singapore
| | - Ewelina Rozycka
- Center for Cancer Research and Cell Biology; Queen's University Belfast; Belfast UK; Current affiliation: School of Biochemistry and Immunology; Trinity College; Dublin, Ireland
| | - Cian M McCrudden
- Center for Cancer Research and Cell Biology; Queen's University Belfast; Belfast UK
| | - Vinay Tergaonkar
- Institute of Molecular and Cell Biology; A*STAR (Agency for Science, Technology and Research); Singapore
| | - Abhishek Gupta
- Institute of Molecular and Cell Biology; A*STAR (Agency for Science, Technology and Research); Singapore
| | - You Bin Lin
- Institute of Molecular and Cell Biology; A*STAR (Agency for Science, Technology and Research); Singapore
| | - Jean Paul Thiery
- Institute of Molecular and Cell Biology; A*STAR (Agency for Science, Technology and Research); Singapore; Department of Biochemistry; Yong Loo Lin School of Medicine; National University of Singapore; Singapore
| | - James T Murray
- Current affiliation: School of Biochemistry and Immunology; Trinity College; Dublin, Ireland
| | - Qi Zeng
- Institute of Molecular and Cell Biology; A*STAR (Agency for Science, Technology and Research); Singapore; Department of Biochemistry; Yong Loo Lin School of Medicine; National University of Singapore; Singapore
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Dynamics of mRNA and polysomal abundance in early 3T3-L1 adipogenesis. BMC Genomics 2014; 15:381. [PMID: 24886538 PMCID: PMC4039748 DOI: 10.1186/1471-2164-15-381] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2013] [Accepted: 05/07/2014] [Indexed: 12/31/2022] Open
Abstract
Background Adipogenesis is a complex process, in which immature pre-adipocytes change morphology, micro-anatomy and physiology to become mature adipocytes. These store and accumulate fat and release diverse hormones. Massive changes in protein content and protein composition of the transforming cell take place within a short time-frame. In a previous study we analyzed changes in the abundance of free and polysomal, i.e. ribosome bound, RNAs in the first hours of adipogenesis in the murine cell line 3T3-L1. Here we analyze changes of mRNA levels and their potential contribution to the changing protein pool by determination of mRNA levels and ribosome binding to mRNAs in 3T3-L1 cells stimulated for adipogenesis. We grouped mRNA species into categories with respect to up- or down-regulated transcription and translation and analyzed the groups regarding specific functionalities based on Gene Ontology (GO). Results A shift towards up-regulation of gene expression in early adipogenesis was detected. Genes up-regulated at the transcriptional (TC:up) and translational (TL:up) level (TC:up/TL:up) are very likely involved in control and logistics of translation. Many of them are known to contain a TOP motif. In the TC:up/TL:unchanged group we detected most of the metal binding proteins and metal transporters. In the TC:unchanged/TL:up group several factors of the olfactory receptor family were identified, while in TC:unchanged/TL:down methylation and repair genes are represented. In the TC:down/TL:up group we detected many signaling factors. The TC:down/TL:unchanged group mainly consists of regulatory factors. Conclusions Within the first hours of adipogenesis, changes in transcriptional and translational regulation take place. Notably, genes with a specific biological or molecular function tend to cluster in groups according to their transcriptional and translational regulation. Electronic supplementary material The online version of this article (doi:10.1186/1471-2164-15-381) contains supplementary material, which is available to authorized users.
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Ríos P, Nunes-Xavier CE, Tabernero L, Köhn M, Pulido R. Dual-specificity phosphatases as molecular targets for inhibition in human disease. Antioxid Redox Signal 2014; 20:2251-73. [PMID: 24206177 DOI: 10.1089/ars.2013.5709] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
SIGNIFICANCE The dual-specificity phosphatases (DUSPs) constitute a heterogeneous group of cysteine-based protein tyrosine phosphatases, whose members exert a pivotal role in cell physiology by dephosphorylation of phosphoserine, phosphothreonine, and phosphotyrosine residues from proteins, as well as other non-proteinaceous substrates. RECENT ADVANCES A picture is emerging in which a selected group of DUSP enzymes display overexpression or hyperactivity that is associated with human disease, especially human cancer, making feasible targeted therapy approaches based on their inhibition. A panoply of molecular and functional studies on DUSPs have been performed in the previous years, and drug-discovery efforts are ongoing to develop specific and efficient DUSP enzyme inhibitors. This review summarizes the current status on inhibitory compounds targeting DUSPs that belong to the MAP kinase phosphatases-, small-sized atypical-, and phosphatases of regenerating liver subfamilies, whose inhibition could be beneficial for the prevention or mitigation of human disease. CRITICAL ISSUES Achieving specificity, potency, and bioavailability are the major challenges in the discovery of DUSP inhibitors for the clinics. Clinical validation of compounds or alternative inhibitory strategies of DUSP inhibition has yet to come. FUTURE DIRECTIONS Further work is required to understand the dual role of many DUSPs in human cancer, their function-structure properties, and to identify their physiologic substrates. This will help in the implementation of therapies based on DUSPs inhibition.
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Affiliation(s)
- Pablo Ríos
- 1 Genome Biology Unit, European Molecular Biology Laboratory , Heidelberg, Germany
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58
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Sharlow ER, Wipf P, McQueeney KE, Bakan A, Lazo JS. Investigational inhibitors of PTP4A3 phosphatase as antineoplastic agents. Expert Opin Investig Drugs 2014; 23:661-73. [DOI: 10.1517/13543784.2014.892579] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Campbell AM, Zhang ZY. Phosphatase of regenerating liver: a novel target for cancer therapy. Expert Opin Ther Targets 2014; 18:555-69. [PMID: 24579927 DOI: 10.1517/14728222.2014.892926] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
INTRODUCTION Phosphatases of regenerating livers (PRLs) are novel oncogenes that interact with many well-established cell signaling pathways that are misregulated in cancer, and are known to drive cancer metastasis when overexpressed. AREAS COVERED This review covers basic information of the discovery and characteristics of the PRL family. We also report findings on the role of PRL in cancer, cell functions and cell signaling. Furthermore, PRL's suitability as a novel drug target is discussed along with current methods being developed to facilitate PRL inhibition. EXPERT OPINION PRLs show great potential as novel drug targets for anticancer therapeutics. Studies indicate that PRL can perturb major cancer pathways such as Src/ERK1/2 and PTEN/PI3K/Akt. Upregulation of PRLs has also been shown to drive cancer metastasis. However, in order to fully realize its therapeutic potential, a deeper understanding of the function of PRL in normal tissue and in cancer must be obtained. Novel and integrated biochemical, chemical, biological, and genetic approaches will be needed to identify PRL substrate(s) and to provide proof-of-concept data on the druggability of the PRL phosphatases.
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Affiliation(s)
- Amanda M Campbell
- Indiana University School of Medicine, Department of Biochemistry and Molecular Biology , John D. Van Nuys Medical Science Building, Room 4053A, 635 Barnhill Drive, Indianapolis, IN 46202-5126 , USA
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Zimmerman MW, McQueeney KE, Isenberg JS, Pitt BR, Wasserloos KA, Homanics GE, Lazo JS. Protein-tyrosine phosphatase 4A3 (PTP4A3) promotes vascular endothelial growth factor signaling and enables endothelial cell motility. J Biol Chem 2014; 289:5904-13. [PMID: 24403062 DOI: 10.1074/jbc.m113.480038] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Protein-tyrosine phosphatase 4A3 (PTP4A3) is highly expressed in multiple human cancers and is hypothesized to have a critical, albeit poorly defined, role in the formation of experimental tumors in mice. PTP4A3 is broadly expressed in many tissues so the cellular basis of its etiological contributions to carcinogenesis may involve both tumor and stromal cells. In particular, PTP4A3 is expressed in the tumor vasculature and has been proposed to be a direct target of vascular endothelial growth factor (VEGF) signaling in endothelial cells. We now provide the first in vivo experimental evidence that PTP4A3 participates in VEGF signaling and contributes to the process of pathological angiogenesis. Colon tumor tissue isolated from Ptp4a3-null mice revealed reduced tumor microvessel density compared with wild type controls. Additionally, vascular cells derived from Ptp4a3-null tissues exhibited decreased invasiveness in an ex vivo wound healing assay. When primary endothelial cells were isolated and cultured in vitro, Ptp4a3-null cells displayed greatly reduced migration compared with wild type cells. Exposure to VEGF led to an increase in Src phosphorylation in wild type endothelial cells, a response that was completely ablated in Ptp4a3-null cells. In loss-of-function studies, reduced VEGF-mediated migration was also observed when human endothelial cells were treated with a small molecule inhibitor of PTP4A3. VEGF-mediated in vivo vascular permeability was significantly attenuated in PTP4A3-deficient mice. These findings strongly support a role for PTP4A3 as an important contributor to endothelial cell function and as a multimodal target for cancer therapy and mitigating VEGF-regulated angiogenesis.
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Affiliation(s)
- Mark W Zimmerman
- From the Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, Pennsylvania 15260
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Xing X, Lian S, Hu Y, Li Z, Zhang L, Wen X, Du H, Jia Y, Zheng Z, Meng L, Shou C, Ji J. Phosphatase of regenerating liver-3 (PRL-3) is associated with metastasis and poor prognosis in gastric carcinoma. J Transl Med 2013; 11:309. [PMID: 24330843 PMCID: PMC3878674 DOI: 10.1186/1479-5876-11-309] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2013] [Accepted: 11/29/2013] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND PRL-3 is a member of phosphatases of regenerating liver family, characterized by phosphatase active domain and C-terminal prenylation motif. Overexpression of PRL-3 has been implicated in multiple cancers. Here we examined the clinical significance of PRL-3 in gastric cancer together with its metastatic biological functions utilizing different structural mutants. METHODS PRL-3 expression was analyzed immunohistochemically in 196 gastric cancer patients and 21 cases of liver metastasis. A series of wild type PRL-3 or its mutant plasmids were expressed in BGC823 cells to investigate the relationship between its catalytic activity, cellular localization and metastatic potential in vitro. RESULTS Positive staining of PRL-3 was observed in 19.4% (38/196) gastric cancer tissues compared with 76.2% (16/21) in liver metastasis. Statistical analysis revealed that PRL-3 expression correlated with lymph node metastasis and vascular invasion (P<0.05). Patients with high PRL-3 expression showed poorer 5-year overall survival (P=0.011). Wild type PRL-3 expressing cells resulted in enhanced migration and invasion ability, which were greatly crippled in form of PRL-3(C104S) or PRL-3(ΔCAAX) mutants accompanied with its alteration in subcellular localization. CONCLUSIONS Metastasis associated protein PRL-3 may serve as a potential prognostic biomarker in human gastric cancer. Both the phosphatase catalytic activity and cellular localization are critical for its function.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | - Chengchao Shou
- Department of gastrointestinal translational research, Peking University Cancer Hospital & Institute, #52 Fu-Cheng Road, Hai-Dian District, Beijing 100142, China.
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