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Bhuiyan MIH, Song S, Yuan H, Begum G, Kofler J, Kahle KT, Yang SS, Lin SH, Alper SL, Subramanya AR, Sun D. WNK-Cab39-NKCC1 signaling increases the susceptibility to ischemic brain damage in hypertensive rats. J Cereb Blood Flow Metab 2017; 37:2780-2794. [PMID: 27798271 PMCID: PMC5536788 DOI: 10.1177/0271678x16675368] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
With-no-lysine kinase (WNK) and Na+-K+-2Cl- cotransporter 1 (NKCC1) are involved in the pathogenesis of hypertension. In this study, we investigated the WNK-NKCC1 signaling pathway in spontaneously hypertensive rats (SHR) and their associated susceptibility to stroke injury. Basal NKCC1 protein levels were higher in SHR than in normotensive Wistar Kyoto (WKY) rat brains. After inducing ischemic stroke, adult male WKY and SHR received either saline or NKCC1 inhibitor bumetanide (10 mg/kg/day, i.p.) starting at 3-h post-reperfusion. NKCC1 inhibition blunted the extent of ischemic infarction in SHR and improved their neurobehavioral functions. Interestingly, ischemia led to increased NKCC1 phosphorylation in SHR but not in WKY rats. Pronounced elevation of WNK1, WNK2 and WNK4 protein and downregulation of WNK3 were detected in ischemic SHR, but not in ischemic WKY rats. Upregulation of WNK-NKCC1 complex in ischemic SHR brain was associated with increased Ca2+-binding protein 39 (Cab39), without increases in Ste20-related proline alanine-rich kinase or oxidative stress-responsive kinase-1. Moreover, subacute middle cerebral artery stroke human brain autopsy exhibited increased expression of NKCC1 protein. We conclude that augmented WNK-Cab39-NKCC1 signaling in SHR is associated with an increased susceptibility to ischemic brain damage and may serve as a novel target for anti-hypertensive and anti-ischemic stroke therapy.
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Affiliation(s)
| | - Shanshan Song
- 1 Department of Neurology, University of Pittsburgh, Pittsburgh, USA
| | - Hui Yuan
- 1 Department of Neurology, University of Pittsburgh, Pittsburgh, USA
| | - Gulnaz Begum
- 1 Department of Neurology, University of Pittsburgh, Pittsburgh, USA
| | - Julia Kofler
- 2 Department of Pathology, University of Pittsburgh, Pittsburgh, USA
| | - Kristopher T Kahle
- 3 Department of Neurosurgery, Yale University School of Medicine, New Haven, USA.,4 Department of Pediatrics, Yale University School of Medicine, New Haven, USA
| | - Sung-Sen Yang
- 5 Division of Nephrology, Department of Medicine, Tri-Service General Hospital, Taipei, Taiwan.,6 Graduate Institute of Medical Sciences, National Defense Medical Center, Taipei, Taiwan
| | - Shih-Hua Lin
- 5 Division of Nephrology, Department of Medicine, Tri-Service General Hospital, Taipei, Taiwan.,6 Graduate Institute of Medical Sciences, National Defense Medical Center, Taipei, Taiwan
| | - Seth L Alper
- 7 Division of Nephrology and Vascular Biology Center, Beth Israel Deaconess Medical Center, Boston, USA.,8 Department of Medicine, Harvard Medical School, Boston, USA
| | - Arohan R Subramanya
- 9 Department of Medicine, Renal-Electrolyte Division, University of Pittsburgh School of Medicine, Pittsburgh, USA
| | - Dandan Sun
- 1 Department of Neurology, University of Pittsburgh, Pittsburgh, USA.,10 Veterans Affairs Pittsburgh Health Care System, Geriatric Research, Educational and Clinical Center, Pittsburgh, USA
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52
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Klameth L, Rath B, Hamilton G. In vitro Cytotoxic Activities of the Oral Platinum(IV) Prodrug Oxoplatin and HSP90 Inhibitor Ganetespib against a Panel of Gastric Cancer Cell Lines. J Cancer 2017; 8:1733-1743. [PMID: 28819369 PMCID: PMC5556635 DOI: 10.7150/jca.17816] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Accepted: 04/01/2017] [Indexed: 12/11/2022] Open
Abstract
Gastric cancer exhibits a poor prognosis and is the third most common cause of cancer death worldwide. Chemotherapy of metastatic gastric cancer is based on combinations of platinum drugs and fluoropyrimidines, with added agents. Oxoplatin is a stable oral platinum(IV) prodrug which is converted to a highly active tetrachlorido(IV) complex under acidic conditions. In the present work, we studied the cytotoxic effects of oxoplatin against a panel of four gastric cancer cell lines in vitro. Furthermore, the role of HSP90 in chemoresistance of these lines was investigated using the specific inhibitor ganetespib. The KATO-III, MKN-1, MKN-28, MKN-45 lines were used in MTT chemosensitivity, cell cycle and apoptosis assays. KATO-III is a signet ring diffuse cell type, MKN-1 an adenosquamous primary, MKN-28 a well-differentiated intestinal type and the MKN-45 a poorly differentiated, diffuse type gastric carcinoma line. Cytotoxicity was tested in MTT assays and intracellular signal transduction with proteome profiler Western blot arrays. Interactions of platinum drugs and ganetespib were calculated with help of the Chou-Talalay method. The prodrug oxoplatin revealed low activity against the four gastric cancer cell lines, whereas the platinum tetrachlorido(IV) complex and cisplatin gave IC50 values of 1-3 µg/ml with increasing chemoresistance observed in the order of MKN-1, KATO-III, MKN-28 to MKN-45. With exception of KATO-III and MKN-28/oxoplatin, all other cell lines featured marked synergistic toxicity with clinically achievable concentrations of ganetespib. Oral administration of a platinum agent such as oxoplatin would be of great value for patients and care providers alike. These results suggest that the oncogene-stabilizing HSP90 chaperone represents an important mediator of chemoresistance in gastric cancer. Ganetespib reduced the phosphorylation of p53, Akt1/2/3 and PRAS40, as well as of WNK1, a kinase which regulates intracellular chloride concentrations. Intracellular chloride was reported to control proliferation of gastric cancer cell lines. Expression of MUC1 was not downregulated in contrast to the expression of CAIX, a prognostic marker in gastric cancer. In conclusion, the HSP90 inhibitor ganetespib synergizes with platinum anticancer drugs and modulates intracellular signal transduction in direction of a less proliferative and aggressive phenotype.
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Affiliation(s)
- Lukas Klameth
- Department for Pathophysiology and Allergy Research, Medical University of Vienna, Vienna, Austria
| | - Barbara Rath
- Department of Surgery, Medical University of Vienna, Vienna, Austria
| | - Gerhard Hamilton
- Department of Surgery, Medical University of Vienna, Vienna, Austria
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53
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Computed determination of the in vitro optimal chemocombinations of sphaeropsidin A with chemotherapeutic agents to combat melanomas. Cancer Chemother Pharmacol 2017; 79:971-983. [DOI: 10.1007/s00280-017-3293-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2016] [Accepted: 03/24/2017] [Indexed: 12/19/2022]
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54
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Abstract
WNK kinases, along with their upstream regulators (CUL3/KLHL3) and downstream targets (the SPAK/OSR1 kinases and the cation-Cl- cotransporters [CCCs]), comprise a signaling cascade essential for ion homeostasis in the kidney and nervous system. Recent work has furthered our understanding of the WNKs in epithelial transport, cell volume homeostasis, and GABA signaling, and uncovered novel roles for this pathway in immune cell function and cell proliferation.
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Affiliation(s)
- Masoud Shekarabi
- Department of Neuroscience, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA
| | - Jinwei Zhang
- Departments of Neurosurgery, Centers for Mendelian Genomics, Yale School of Medicine, New Haven, CT 06477, USA; MRC Protein Phosphorylation and Ubiquitylation Unit, College of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland, UK
| | - Arjun R Khanna
- Department of Neurosurgery, Massachusetts General Hospital, Boston, MA 02114, USA; Department of Neurosurgery, Harvard Medical School, Boston, MA 02115, USA
| | - David H Ellison
- Division of Nephrology & Hypertension, Department of Medicine, Oregon Health & Science University, Portland, Oregon 97239, USA; VA Portland Health Care System, Portland, OR 97239, USA
| | - Eric Delpire
- Department of Anesthesiology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Kristopher T Kahle
- Departments of Neurosurgery, Pediatrics, and Cellular & Molecular Physiology, Centers for Mendelian Genomics, Yale School of Medicine, New Haven, CT 06477, USA.
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55
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Abstract
The pseudokinase complement of the human kinase superfamily consists of approximately 60 signaling proteins, which lacks one or more of the amino acids typically required to correctly align ATP and metal ions, and phosphorylate protein substrates. Recent studies in the pseudokinase field have begun to expose the biological relevance of pseudokinases, which are now thought to perform a diverse range of physiological roles and are connected to a multitude of human diseases, including cancer. In this review, we discuss how and why members of the 'pseudokinome' represent important new targets for drug discovery, and describe how knowledge of protein structure and function provides informative clues to help guide the rational chemical design or repurposing of inhibitors to target pseudokinases.
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56
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Hertz L, Chen Y. Importance of astrocytes for potassium ion (K+) homeostasis in brain and glial effects of K+ and its transporters on learning. Neurosci Biobehav Rev 2016; 71:484-505. [DOI: 10.1016/j.neubiorev.2016.09.018] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Revised: 08/12/2016] [Accepted: 09/23/2016] [Indexed: 10/20/2022]
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57
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Abstract
The with-no-lysine (K) (WNK) kinases are an atypical family of protein kinases that regulate ion transport across cell membranes. Mutations that result in their overexpression cause hypertension-related disorders in humans. Of the four mammalian WNKs, only WNK1 is expressed throughout the body. We report that WNK1 inhibits autophagy, an intracellular degradation pathway implicated in several human diseases. Using small-interfering RNA-mediated WNK1 knockdown, we show autophagosome formation and autophagic flux are accelerated. In cells with reduced WNK1, basal and starvation-induced autophagy is increased. We also show that depletion of WNK1 stimulates focal class III phosphatidylinositol 3-kinase complex (PI3KC3) activity, which is required to induce autophagy. Depletion of WNK1 increases the expression of the PI3KC3 upstream regulator unc-51-like kinase 1 (ULK1), its phosphorylation, and activation of the kinase upstream of ULK1, the AMP-activated protein kinase. In addition, we show that the N-terminal region of WNK1 binds to the UV radiation resistance-associated gene (UVRAG) in vitro and WNK1 partially colocalizes with UVRAG, a component of a PI3KC3 complex. This colocalization decreases upon starvation of cells. Depletion of the SPS/STE20-related proline-alanine-rich kinase, a WNK1-activated enzyme, also induces autophagy in nutrient-replete or -starved conditions, but depletion of the related kinase and WNK1 substrate, oxidative stress responsive 1, does not. These results indicate that WNK1 inhibits autophagy by multiple mechanisms.
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Shyamasundar S, Lim JP, Bay BH. miR-93 inhibits the invasive potential of triple-negative breast cancer cells in vitro via protein kinase WNK1. Int J Oncol 2016; 49:2629-2636. [PMID: 27840899 DOI: 10.3892/ijo.2016.3761] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2016] [Accepted: 10/10/2016] [Indexed: 11/06/2022] Open
Abstract
Despite advances in treatment, the highly metastatic nature of breast tumors has given rise to the urgent need for development of novel therapeutic and prognostic markers. miR-93 is known to regulate the epithelial to mesenchymal transition process and to influence metastatic spread in breast carcinoma, although the exact mechanism(s)/genes involved remain unknown. In the present study, we examined the role of miR-93 in MDA-MB-231 breast cancer cells. Overexpression of mature miR-93-5p in MDA-MB-231 cells decreased cell migratory capability and invasive potential, as well as increased adhesion. In contrast, inhibition of miR-93 induced the opposite effects. miRNA-mRNA target prediction (TargetScan) identified WNK lysine deficient protein kinase 1 (WNK1), which is known to interact with diverse signaling pathways and regulate cell proliferation, survival, angiogenesis and metastasis, as one of the potential targets of miR-93. Furthermore, we showed by luciferase assay that WNK1 is a putative miR-93 target. siRNA mediated silencing of WNK1 also decreased the invasive ability of the cells, suggesting that the effects of miR-93 may be attributed at least in part to decreased WNK1 expression. Further in vivo studies are required to ascertain the miR-93-WNK1-metastasis cascade, that has potential implications in breast cancer therapy.
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Affiliation(s)
- Sukanya Shyamasundar
- Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117594, Singapore
| | - Jia Pei Lim
- Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117594, Singapore
| | - Boon Huat Bay
- Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117594, Singapore
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59
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Toda-Ishii M, Akaike K, Suehara Y, Mukaihara K, Kubota D, Kohsaka S, Okubo T, Mitani K, Mogushi K, Takagi T, Kaneko K, Yao T, Saito T. Clinicopathological effects of protein phosphatase 2, regulatory subunit A, alpha mutations in gastrointestinal stromal tumors. Mod Pathol 2016; 29:1424-1432. [PMID: 27469332 DOI: 10.1038/modpathol.2016.138] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2016] [Revised: 06/13/2016] [Accepted: 06/13/2016] [Indexed: 02/07/2023]
Abstract
Recently, several studies have reported that dysfunctions in protein phosphatase 2A (PP2A) caused by alterations in protein phosphatase 2 regulatory subunit A, alpha (PPP2R1A) are responsible for tumorigenesis and tumor progression in several types of cancers. The impact of PPP2R1A mutations remains unknown in gastrointestinal stromal tumors (GISTs), although mutations in KIT and PDGFRA, which result in constitutive activation of the receptor tyrosine kinase pathway, are important in GIST tumorigenesis. In this study, we performed mutation analysis of PPP2R1A to examine the frequency of PPP2R1A mutations and their clinicopathological correlation in 94 GIST cases. In addition, we performed an in vitro analysis to investigate the effects of PPP2R1A mutations on cell proliferation and kinase phosphorylation in GIST cells. Seventeen GIST cases (18%) harbored mutations in PPP2R1A. All but one of these 17 cases harbored a KIT, PDGFRA, HRAS, NRAS, or KRAS mutation as the oncogenic driver mutation, and the remaining case was immunohistochemically negative for succinate dehydrogenase B (SDHB). Multivariate analysis showed that larger tumor size, higher mitotic rate, and PPP2R1A mutation are independent prognostic factors for overall survival; however, PPP2R1A mutation was not an independent prognostic factor for disease-free survival. The transduction of GIST cells with mutant PPP2R1A induced an accelerated growth rate via increased phosphorylation of Akt1/2, ERK1/2, and WNK1, a kinase associated with angiogenesis. In addition, the transduction of GIST cells with mutant PPP2R1A caused increased c-kit phosphorylation, suggesting that c-kit is also a target of PP2A, reinforcing the tumorigenic capabilities of c-kit. Furthermore, the transducing GIST cells with wild-type PP2A dephosphorylated mutant c-kit. This study provides a new insight into the biology of GISTs and their phosphatase activity, and activated PP2A could be a therapeutic target in GISTs.
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Affiliation(s)
- Midori Toda-Ishii
- Department of Human Pathology, Juntendo University School of Medicine, Tokyo, Japan.,Department of Orthopaedic Surgery, Juntendo University School of Medicine, Tokyo, Japan
| | - Keisuke Akaike
- Department of Human Pathology, Juntendo University School of Medicine, Tokyo, Japan.,Department of Orthopaedic Surgery, Juntendo University School of Medicine, Tokyo, Japan
| | - Yoshiyuki Suehara
- Department of Orthopaedic Surgery, Juntendo University School of Medicine, Tokyo, Japan
| | - Kenta Mukaihara
- Department of Human Pathology, Juntendo University School of Medicine, Tokyo, Japan.,Department of Orthopaedic Surgery, Juntendo University School of Medicine, Tokyo, Japan
| | - Daisuke Kubota
- Department of Orthopaedic Surgery, Juntendo University School of Medicine, Tokyo, Japan
| | - Shinji Kohsaka
- Department of Medical Genomics, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Taketo Okubo
- Department of Orthopaedic Surgery, Juntendo University School of Medicine, Tokyo, Japan
| | - Keiko Mitani
- Department of Human Pathology, Juntendo University School of Medicine, Tokyo, Japan
| | - Kaoru Mogushi
- Center for Genomic and Regenerative Medicine, Juntendo University School of Medicine, Tokyo, Japan
| | - Tatsuya Takagi
- Department of Orthopaedic Surgery, Juntendo University School of Medicine, Tokyo, Japan
| | - Kazuo Kaneko
- Department of Orthopaedic Surgery, Juntendo University School of Medicine, Tokyo, Japan
| | - Takashi Yao
- Department of Human Pathology, Juntendo University School of Medicine, Tokyo, Japan
| | - Tsuyoshi Saito
- Department of Human Pathology, Juntendo University School of Medicine, Tokyo, Japan
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60
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Abstract
WNK (With-No-Lysine (K)) kinases are serine-threonine kinases characterized by an atypical placement of a catalytic lysine within the kinase domain. Mutations in human WNK1 or WNK4 cause an autosomal dominant syndrome of hypertension and hyperkalemia, reflecting the fact that WNK kinases are critical regulators of renal ion transport processes. Here, the role of WNKs in the regulation of ion transport processes in vertebrate and invertebrate renal function, cellular and organismal osmoregulation, and cell migration and cerebral edema will be reviewed, along with emerging literature demonstrating roles for WNKs in cardiovascular and neural development, Wnt signaling, and cancer. Conserved roles for these kinases across phyla are emphasized.
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Affiliation(s)
| | - Andreas Jenny
- Albert Einstein College of Medicine, New York, NY, United States.
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61
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Pointer KB, Clark PA, Eliceiri KW, Salamat MS, Robertson GA, Kuo JS. Administration of Non-Torsadogenic human Ether-à-go-go-Related Gene Inhibitors Is Associated with Better Survival for High hERG-Expressing Glioblastoma Patients. Clin Cancer Res 2016; 23:73-80. [PMID: 27635088 DOI: 10.1158/1078-0432.ccr-15-3169] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2016] [Revised: 08/12/2016] [Accepted: 09/03/2016] [Indexed: 12/29/2022]
Abstract
PURPOSE Glioblastoma is the most malignant primary brain tumor, with a median survival of less than 2 years. More effective therapeutic approaches are needed to improve clinical outcomes. EXPERIMENTAL DESIGN Glioblastoma patient-derived cells (GPDC) were isolated from patient glioblastomas and implanted in mice to form xenografts. IHC was performed for human Ether-à-go-go-Related Gene (hERG) expression and tumor proliferation. Sphere-forming assays with the hERG blocker E-4031 were performed on a high and low hERG-expressing lines. A glioblastoma tissue microarray (TMA; 115 patients) was used to correlate hERG expression with patient survival. Clinical data were analyzed to determine whether patient survival was affected by incidental administration of hERG inhibitory drugs and the correlative effect of patient glioblastoma hERG expression levels. RESULTS hERG expression was upregulated in glioblastoma xenografts with higher proliferative indices. High hERG-expressing GPDCs showed a reduction in sphere formation when treated with hERG inhibitors compared with low hERG-expressing GPDCs. Glioblastoma TMA analysis showed worse survival for glioblastoma patients with high hERG expression versus low expression-43.5 weeks versus 60.9 weeks, respectively (P = 0.022). Furthermore, patients who received at least one hERG blocker had a better survival rate compared with patients who did not (P = 0.0015). Subgroup analysis showed that glioblastoma patients with high hERG expression who received hERG blockers had improved survival (P = 0.0458). There was no difference in survival for low hERG-expressing glioblastoma patients who received hERG blockers (P = 0.4136). CONCLUSIONS Our findings suggest that hERG is a potential glioblastoma survival marker, and that already approved drugs with non-torsadogenic hERG inhibitory activity may potentially be repurposed as adjuvant glioblastoma therapy in high hERG-expressing glioblastoma patients. Clin Cancer Res; 23(1); 73-80. ©2016 AACRSee related commentary by Arcangeli and Becchetti, p. 3.
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Affiliation(s)
- Kelli B Pointer
- Department of Neurological Surgery, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, Wisconsin.,Medical Scientist Training Program, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, Wisconsin.,Cellular and Molecular Biology, University of Wisconsin-Madison, Madison, Wisconsin.,Laboratory for Optical and Computational Instrumentation (LOCI), University of Wisconsin-Madison, Madison, Wisconsin
| | - Paul A Clark
- Department of Neurological Surgery, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, Wisconsin
| | - Kevin W Eliceiri
- Laboratory for Optical and Computational Instrumentation (LOCI), University of Wisconsin-Madison, Madison, Wisconsin.,Carbone Cancer Center, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, Wisconsin
| | - M Shahriar Salamat
- Department of Pathology and Laboratory Medicine, University of Wisconsin-Madison, Madison, Wisconsin
| | - Gail A Robertson
- Department of Neuroscience, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, Wisconsin. .,Cardiovascular Research Center, University of Wisconsin-Madison, Madison, Wisconsin
| | - John S Kuo
- Department of Neurological Surgery, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, Wisconsin. .,Medical Scientist Training Program, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, Wisconsin.,Cellular and Molecular Biology, University of Wisconsin-Madison, Madison, Wisconsin.,Carbone Cancer Center, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, Wisconsin.,Department of Surgery, National University of Singapore, Singapore
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62
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Zhu W, Carney KE, Pigott VM, Falgoust LM, Clark PA, Kuo JS, Sun D. Glioma-mediated microglial activation promotes glioma proliferation and migration: roles of Na+/H+ exchanger isoform 1. Carcinogenesis 2016; 37:839-851. [PMID: 27287871 PMCID: PMC5008247 DOI: 10.1093/carcin/bgw068] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Revised: 04/29/2016] [Accepted: 05/15/2016] [Indexed: 12/31/2022] Open
Abstract
Microglia play important roles in extracellular matrix remodeling, tumor invasion, angiogenesis, and suppression of adaptive immunity in glioma. Na(+)/H(+) exchanger isoform 1 (NHE1) regulates microglial activation and migration. However, little is known about the roles of NHE1 in intratumoral microglial activation and microglia-glioma interactions. Our study revealed up-regulation of NHE1 protein expression in both glioma cells and tumor-associated Iba1(+) microglia in glioma xenografts and glioblastoma multiforme microarrays. Moreover, we observed positive correlation of NHE1 expression with Iba1 intensity in microglia/macrophages. Glioma cells, via conditioned medium or non-contact glioma-microglia co-cultures, concurrently upregulated microglial expression of NHE1 protein and other microglial activation markers (iNOS, arginase-1, TGF-β, IL-6, IL-10 and the matrix metalloproteinases MT1-MMP and MMP9). Interestingly, glioma-stimulated microglia reciprocally enhanced glioma proliferation and migration. Most importantly, inhibition of microglial NHE1 activity via small interfering RNA (siRNA) knockdown or the potent NHE1-specific inhibitor HOE642 significantly attenuated microglial activation and abolished microglia-stimulated glioma migration and proliferation. Taken together, our findings provide the first evidence that NHE1 function plays an important role in glioma-microglia interactions, enhancing glioma proliferation and invasion by stimulating microglial release of soluble factors. NHE1 upregulation is a novel marker of the glioma-associated microglial activation phenotype. Inhibition of NHE1 represents a novel glioma therapeutic strategy by targeting tumor-induced microglial activation.
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Affiliation(s)
- Wen Zhu
- Department of Neurology, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Karen E. Carney
- Department of Neurology, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Victoria M. Pigott
- Department of Neurology, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Lindsay M. Falgoust
- Department of Neurology, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Paul A. Clark
- Department of Neurological Surgery
- Carbone Cancer Center, University of Wisconsin School of Medicine and Public Health, Madison, WI 53792, USA and
| | - John S. Kuo
- Department of Neurological Surgery
- Carbone Cancer Center, University of Wisconsin School of Medicine and Public Health, Madison, WI 53792, USA and
| | - Dandan Sun
- Department of Neurology, University of Pittsburgh, Pittsburgh, PA 15213, USA
- Veterans Affairs Pittsburgh Health Care System, Geriatric Research, Educational and Clinical Center, Pittsburgh, PA, USA
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63
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Cong D, Zhu W, Kuo JS, Hu S, Sun D. Ion transporters in brain tumors. Curr Med Chem 2016; 22:1171-81. [PMID: 25620102 DOI: 10.2174/0929867322666150114151946] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2014] [Revised: 01/05/2015] [Accepted: 01/08/2015] [Indexed: 11/22/2022]
Abstract
Ion transporters are important in regulation of ionic homeostasis, cell volume, and cellular signal transduction under physiological conditions. They have recently emerged as important players in cancer progression. In this review, we discussed two important ion transporter proteins, sodium-potassium-chloride cotransporter isoform 1 (NKCC-1) and sodium-hydrogen exchanger isoform 1 (NHE-1) in Glioblastoma multiforme (GBM) and other malignant tumors. NKCC-1 is a Na(+)- dependent Cl(-) transporter that mediates the movement of Na(+), K(+), and Cl(-) ions across the plasma membrane and maintains cell volume and intracellular K(+) and Cl(-) homeostasis. NHE-1 is a ubiquitously expressed cell membrane protein which regulates intracellular pH (pH(i)) and extracellular pH (pH(e)) homeostasis and cell volume. Here, we summarized recent pre-clinical experimental studies on NKCC-1 and NHE-1 in GBM and other malignant tumors, such as breast cancer, hepatocellular carcinoma, and lung cancer cells. These studies illustrated that pharmacological inhibition or down-regulation of these ion transporter proteins reduces proliferation, increases apoptosis, and suppresses migration and invasion of cancer cells. These new findings reveal the potentials of these ion transporters as new targets for cancer diagnosis and/or treatment.
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Affiliation(s)
| | | | | | | | - Dandan Sun
- Department of Neurology, University of Pittsburgh Medical School, S-598 South Biomedical Science Tower (BST), 3500 Terrace St., Pittsburgh, PA 15213, USA.
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64
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Zhou X, Naguro I, Ichijo H, Watanabe K. Mitogen-activated protein kinases as key players in osmotic stress signaling. Biochim Biophys Acta Gen Subj 2016; 1860:2037-52. [PMID: 27261090 DOI: 10.1016/j.bbagen.2016.05.032] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Accepted: 05/21/2016] [Indexed: 11/29/2022]
Abstract
BACKGROUND Osmotic stress arises from the difference between intracellular and extracellular osmolality. It induces cell swelling or shrinkage as a consequence of water influx or efflux, which threatens cellular activities. Mitogen-activated protein kinases (MAPKs) play central roles in signaling pathways in osmotic stress responses, including the regulation of intracellular levels of inorganic ions and organic osmolytes. SCOPE OF REVIEW The present review summarizes the cellular osmotic stress response and the function and regulation of the vertebrate MAPK signaling pathways involved. We also describe recent findings regarding apoptosis signal-regulating kinase 3 (ASK3), a MAP3K member, to demonstrate its regulatory effects on signaling molecules beyond MAPKs. MAJOR CONCLUSIONS MAPKs are rapidly activated by osmotic stress and have diverse roles, such as cell volume regulation, gene expression, and cell survival/death. There is significant cell type specificity in the function and regulation of MAPKs. Based on its activity change during osmotic stress and its regulation of the WNK1-SPAK/OSR1 pathway, ASK3 is expected to play important roles in osmosensing mechanisms and cellular functions related to osmoregulation. GENERAL SIGNIFICANCE MAPKs are essential for various cellular responses to osmotic stress; thus, the identification of the upstream regulators of MAPK pathways will provide valuable clues regarding the cellular osmosensing mechanism, which remains elusive in mammals. The elucidation of in vivo MAPK functions is also important because osmotic stress in physiological and pathophysiological conditions often results from changes in the intracellular osmolality. These studies potentially contribute to the establishment of therapeutic strategies against diseases that accompany osmotic perturbation.
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Affiliation(s)
- Xiangyu Zhou
- Laboratory of Cell Signaling, Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Isao Naguro
- Laboratory of Cell Signaling, Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Hidenori Ichijo
- Laboratory of Cell Signaling, Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Kengo Watanabe
- Laboratory of Cell Signaling, Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
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Tang BL. (WNK)ing at death: With-no-lysine (Wnk) kinases in neuropathies and neuronal survival. Brain Res Bull 2016; 125:92-8. [PMID: 27131446 DOI: 10.1016/j.brainresbull.2016.04.017] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2016] [Revised: 04/11/2016] [Accepted: 04/24/2016] [Indexed: 12/22/2022]
Abstract
Members of With-no-lysine (WNK) family of serine-threonine kinase are key regulators of chloride ion transport in diverse cell types, controlling the activity and the surface expression of cation-chloride (Na(+)/K(+)-Cl(-)) co-transporters. Mutations in WNK1 and WNK4 are linked to a hereditary form of hypertension, and WNKs have been extensively investigated pertaining to their roles in renal epithelial ion homeostasis. However, some members of the WNK family and their splice isoforms are also expressed in the mammalian brain, and have been implicated in aspects of hereditary neuropathy as well as neuronal and glial survival. WNK2, which is exclusively enriched in neurons, is well known as an anti-proliferative tumor suppressor. WNK3, on the other hand, appears to promote cell survival as its inhibition enhances neuronal apoptosis. However, loss of WNK3 has been recently shown to reduce ischemia-associated brain damage. In this review, I surveyed the potentially context-dependent roles of WNKs in neurological disorders and neuronal survival.
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Affiliation(s)
- Bor Luen Tang
- Department of Biochemistry, Yong Loo Lin School of Medicine, Singapore; NUS Graduate School for Integrative Sciences and Engineering, National University of Singapore, Singapore.
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Sun PL, Jin Y, Park SY, Kim H, Park E, Jheon S, Kim K, Lee CT, Chung JH. Expression of Na+-K+-2Cl- cotransporter isoform 1 (NKCC1) predicts poor prognosis in lung adenocarcinoma and EGFR-mutated adenocarcinoma patients. QJM 2016; 109:237-44. [PMID: 26559081 DOI: 10.1093/qjmed/hcv207] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Accepted: 10/29/2015] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND Sodium-potassium-chloride cotransporter isoform 1 (NKCC1) is an active ions cotransporter and modulates cellular volume and migration. NKCC1 blockers can inhibit cancer cell growth. AIM We aimed to elucidate the expression and prognostic significance of NKCC1 in non-small cell lung cancer (NSCLC). METHODS We retrospectively analyzed 788 NSCLC patients with either adenocarcinoma (n = 503) or squamous cell carcinoma (n = 285) by immunohistochemistry to correlate NKCC1 expression with clinicopathologic and survival outcomes. RESULTS In adenocarcinoma, high NKCC1 expression was associated with larger tumor size (P = 0.013), vascular invasion (P < 0.001), lymphatic invasion (P < 0.001), perineural invasion (P = 0.019) and advanced pathologic stage (P < 0.001), but there are no significant correlations between NKCC1 expression and clinicopathological parameters in squamous cell carcinoma. Patients with high NKCC1 expression had significantly shorter disease-free survival (DFS;P < 0.001) and shorter overall survival (OS;P < 0.001) than those with low NKCC1 expression in adenocarcinoma. In squamous cell carcinoma, NKCC1 expression was not associated with prognosis. Multivariate analysis revealed that high NKCC1 expression was an independent prognostic factor for DFS in lung adenocarcinomas (HR, 1.709; 95% CI 1.029-2.130;P = 0.033) and for OS inEGFR-mutated adenocarcinoma patients (HR, 3.165; 95% CI 1.424-7.035;P = 0.005). CONCLUSION NKCC1 high expression predicted a bad clinical outcome for lung adenocarcinoma patients andEGFR-mutated subgroup. Therefore, NKCC1 may play a role in lung adenocarcinoma and novel therapeutic tactics could be developed by targeting NKCC1 protein.
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Affiliation(s)
- Ping-Li Sun
- From the Department of Pathology, Second Hospital of Jilin University, Changchun, Jilin 130021, P.R. China
| | - Yan Jin
- Department of Pathology, Fudan University Shanghai Cancer Center, Shanghai, China
| | - Soo Young Park
- Department of Pathology, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, Republic of Korea
| | - Hyojin Kim
- Department of Pathology, Seoul National University Hospital, Seoul National University College of Medicine, Jongno-Gu, Seoul, Republic of Korea
| | - Eunhyang Park
- Department of Pathology, Seoul National University Hospital, Seoul National University College of Medicine, Jongno-Gu, Seoul, Republic of Korea
| | - Sanghoon Jheon
- Department of Thoracic and Cardiovascular Surgery, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, Republic of Korea
| | - Kwhanmien Kim
- Department of Thoracic and Cardiovascular Surgery, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, Republic of Korea
| | - Choon-Taek Lee
- Department of Internal Medicine, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, Republic of Korea
| | - Jin-Haeng Chung
- Department of Pathology, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, Republic of Korea
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Huberfeld G, Vecht CJ. Seizures and gliomas — towards a single therapeutic approach. Nat Rev Neurol 2016; 12:204-16. [DOI: 10.1038/nrneurol.2016.26] [Citation(s) in RCA: 118] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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Guerra B, Fischer M, Schaefer S, Issinger OG. The kinase inhibitor D11 induces caspase-mediated cell death in cancer cells resistant to chemotherapeutic treatment. JOURNAL OF EXPERIMENTAL & CLINICAL CANCER RESEARCH : CR 2015; 34:125. [PMID: 26480820 PMCID: PMC4612421 DOI: 10.1186/s13046-015-0234-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Accepted: 10/05/2015] [Indexed: 01/30/2023]
Abstract
Background Multi-drug resistance and predisposition to metastasize are major clinical problems in cancer treatment. Malignant primary brain tumor and pancreatic cancer are two well-known examples of malignant tumors resistant to conventional therapies where aberrant EGFR-mediated and NF-κB signal transduction pathways are likely to play an important role. We have recently identified 1,3-Dichloro-6-[(E)-((4-methoxyphenyl)imino)methyl] diben-zo(b,d) furan-2,7-diol (D11) as a potent and selective inhibitor of CK2 a serine/threonine protein kinase that modulates the aforementioned signaling cascades. Methods Human cancer cell lines (glioblastoma and pancreatic adenocarcinoma) resistant to conventional chemotherapeutic agents were incubated with increasing concentrations of D11 for variable amounts of time. Cell viability, cell death and effects on major signal transduction pathways deregulated in cancer cells were analyzed by ELISA, FACS and Western blot-based assays, respectively. Moreover, effects on cell migration and in cell protein-protein association were investigated by wound-healing and in situ proximity ligation assays, respectively. Results We show here, that D11 treatment leads to i) significant caspase-mediated apoptotic cell death, ii) down-regulation of EGFR expression and iii) inhibition of NF-κB transcriptional activity. Furthermore, cell exposure to D11 results in impaired cell migration and correlates with reduced expression of the ion co-transporter and cell volume regulator Na+-K+-2Cl− (NKCC1). Conclusions Data reported here underline the therapeutic potential of D11 with respect to certain types of cancer that carry aberrant intracellular signaling cascades and/or exhibit sustained cell migration and suggest a new therapeutic strategy against chemotherapy resistance. Electronic supplementary material The online version of this article (doi:10.1186/s13046-015-0234-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Barbara Guerra
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark.
| | - Mette Fischer
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark
| | - Susanne Schaefer
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark
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Mathieu V, Chantôme A, Lefranc F, Cimmino A, Miklos W, Paulitschke V, Mohr T, Maddau L, Kornienko A, Berger W, Vandier C, Evidente A, Delpire E, Kiss R. Sphaeropsidin A shows promising activity against drug-resistant cancer cells by targeting regulatory volume increase. Cell Mol Life Sci 2015; 72:3731-46. [PMID: 25868554 DOI: 10.1007/s00018-015-1902-6] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2014] [Revised: 03/10/2015] [Accepted: 04/02/2015] [Indexed: 12/19/2022]
Abstract
Despite the recent advances in the treatment of tumors with intrinsic chemotherapy resistance, such as melanoma and renal cancers, their prognosis remains poor and new chemical agents with promising activity against these cancers are urgently needed. Sphaeropsidin A, a fungal metabolite whose anticancer potential had previously received little attention, was isolated from Diplodia cupressi and found to display specific anticancer activity in vitro against melanoma and kidney cancer subpanels in the National Cancer Institute (NCI) 60-cell line screen. The NCI data revealed a mean LC50 of ca. 10 µM and a cellular sensitivity profile that did not match that of any other agent in the 765,000 compound database. Subsequent mechanistic studies in melanoma and other multidrug-resistant in vitro cancer models showed that sphaeropsidin A can overcome apoptosis as well as multidrug resistance by inducing a marked and rapid cellular shrinkage related to the loss of intracellular Cl(-) and the decreased HCO3 (-) concentration in the culture supernatant. These changes in ion homeostasis and the absence of effects on the plasma membrane potential were attributed to the sphaeropsidin A-induced impairment of regulatory volume increase (RVI). Preliminary results also indicate that depending on the type of cancer, the sphaeropsidin A effects on RVI could be related to Na-K-2Cl electroneutral cotransporter or Cl(-)/HCO3 (-) anion exchanger(s) targeting. This study underscores the modulation of ion-transporter activity as a promising therapeutic strategy to combat drug-resistant cancers and identifies the fungal metabolite, sphaeropsidin A, as a lead to develop anticancer agents targeting RVI in cancer cells.
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Affiliation(s)
- Véronique Mathieu
- Laboratoire de Cancérologie et de Toxicologie Expérimentale, Faculté de Pharmacie, Université Libre de Bruxelles (ULB), Campus de la Plaine, Boulevard du Triomphe, 1050, Brussels, Belgium.
| | - Aurélie Chantôme
- Inserm UMR 1069, Université François Rabelais and network "Ion channels and cancer - Canceropole Grand Ouest", Tours, France
| | - Florence Lefranc
- Service de Neurochirurgie, Hôpital Erasme, Université Libre de Bruxelles, Brussels, Belgium
| | - Alessio Cimmino
- Dipartimento di Scienze Chimiche, Università di Napoli Federico II, Complesso Universitario Monte Sant'Angelo, Via Cintia 4, 80126, Naples, Italy
| | - Walter Miklos
- Department of Medicine I, Institute of Cancer Research and Comprehensive Cancer Center, Medical University of Vienna, Vienna, Austria
| | - Verena Paulitschke
- Department of Dermatology, Medical University of Vienna, Vienna, Austria
| | - Thomas Mohr
- Department of Medicine I, Institute of Cancer Research and Comprehensive Cancer Center, Medical University of Vienna, Vienna, Austria
| | - Lucia Maddau
- Dipartimento di Agraria, Sezione di Patologia vegetale ed Entomologia, Università degli Studi di Sassari, Viale Italia 39, 07100, Sassari, Italy
| | - Alexander Kornienko
- Department of Chemistry and Biochemistry, Texas State University, San Marcos, TX, 78666, USA
| | - Walter Berger
- Department of Medicine I, Institute of Cancer Research and Comprehensive Cancer Center, Medical University of Vienna, Vienna, Austria
| | - Christophe Vandier
- Inserm UMR 1069, Université François Rabelais and network "Ion channels and cancer - Canceropole Grand Ouest", Tours, France
| | - Antonio Evidente
- Dipartimento di Scienze Chimiche, Università di Napoli Federico II, Complesso Universitario Monte Sant'Angelo, Via Cintia 4, 80126, Naples, Italy
| | - Eric Delpire
- Department of Anesthesiology, Vanderbilt University Medical School, Nashville, TN, USA
| | - Robert Kiss
- Laboratoire de Cancérologie et de Toxicologie Expérimentale, Faculté de Pharmacie, Université Libre de Bruxelles (ULB), Campus de la Plaine, Boulevard du Triomphe, 1050, Brussels, Belgium
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Abstract
Protein phosphorylation lies at the heart of cell signalling, and somatic mutation(s) in kinases drives and sustains a multitude of human diseases, including cancer. The human protein kinase superfamily (the kinome) encodes approximately 50 'pseudokinases', which were initially predicted to be incapable of dynamic cell signalling when compared with canonical enzymatically active kinases. This assumption was supported by bioinformatics, which showed that amino acid changes at one or more key loci, making up the nucleotide-binding site or phosphotransferase machinery, were conserved in multiple vertebrate and non-vertebrate pseudokinase homologues. Protein kinases are highly attractive targets for drug discovery, as evidenced by the approval of almost 30 kinase inhibitors in oncology, and the successful development of the dual JAK1/2 (Janus kinase 1/2) inhibitor ruxolitinib for inflammatory indications. However, for such a large (>550) protein family, a remarkable number have still not been analysed at the molecular level, and only a surprisingly small percentage of kinases have been successfully targeted clinically. This is despite evidence that many are potential candidates for the development of new therapeutics. Indeed, several recent reports confirm that disease-associated pseudokinases can bind to nucleotide co-factors at concentrations achievable in the cell. Together, these findings suggest that drug targeting using either ATP-site or unbiased ligand-discovery approaches should now be attempted using the validation technology currently employed to evaluate their classic protein kinase counterparts. In the present review, we discuss members of the human pseudokinome repertoire, and catalogue somatic amino acid pseudokinase mutations that are emerging as the depth and clinical coverage of the human cancer pseudokinome expand.
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Cong D, Zhu W, Shi Y, Pointer KB, Clark PA, Shen H, Kuo JS, Hu S, Sun D. Upregulation of NHE1 protein expression enables glioblastoma cells to escape TMZ-mediated toxicity via increased H⁺ extrusion, cell migration and survival. Carcinogenesis 2014; 35:2014-24. [PMID: 24717311 DOI: 10.1093/carcin/bgu089] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Sodium-hydrogen exchanger isoform 1 (NHE1) plays a role in survival and migration/invasion of several cancers and is an emerging new therapeutic target. However, the role of NHE1 in glioblastoma and the interaction of NHE1 expression and function in glioblastoma cells with cytotoxic temozolomide (TMZ) therapy remain unknown. In this study, we detected high levels of NHE1 protein only in primary human glioma cells (GC), glioma xenografts and glioblastoma, but not in human neural stem cells or astrocytes. GC exhibited an alkaline resting pHi (7.46±0.04) maintained by robust NHE1-mediated H(+) extrusion. GC treatment with TMZ for 2-24h triggered a transient decrease in pHi, which recovered by 48h and correlated with concurrent upregulation of NHE1 protein expression. NHE1 protein was colocalized with ezrin at lamellipodia and probably involved in GC migration. The TMZ-treated GC exhibited increased migration and invasion, which was attenuated by addition of NHE1 inhibitor HOE-642. Most importantly, NHE1 inhibition prevented prosurvival extracellular signal-regulated kinase activation and accelerated TMZ-induced apoptosis. Taken together, our study provides the first evidence that GC upregulate NHE1 protein to maintain alkaline pHi. Combining TMZ therapy with NHE1 inhibition suppresses GC migration and invasion, and also augments TMZ-induced apoptosis. These findings strongly suggest that NHE1 is an important cytoprotective mechanism in GC and presents a new therapeutic strategy of combining NHE1 inhibition and TMZ chemotherapy.
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Affiliation(s)
- Damin Cong
- Department of Neurological Surgery, The Second Affiliated Hospital of the Harbin Medical University, Harbin 150086, China, Department of Neurology, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Wen Zhu
- Department of Neurology, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Yejie Shi
- Department of Neurology, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Kelli B Pointer
- Department of Neurological Surgery, University of Wisconsin, Madison, WI 53705, USA
| | - Paul A Clark
- Department of Neurological Surgery, University of Wisconsin, Madison, WI 53705, USA
| | - Hongmei Shen
- Department of Surgery, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - John S Kuo
- Department of Neurological Surgery, University of Wisconsin, Madison, WI 53705, USA, Carbone Cancer Center, University of Wisconsin, Madison, WI 53705, USA and, Pittsburgh, PA 15213, USA and
| | - Shaoshan Hu
- Department of Neurological Surgery, The Second Affiliated Hospital of the Harbin Medical University, Harbin 150086, China
| | - Dandan Sun
- Department of Neurological Surgery, The Second Affiliated Hospital of the Harbin Medical University, Harbin 150086, China, Department of Neurology, University of Pittsburgh, Pittsburgh, PA 15213, USA, Veterans Affairs Pittsburgh Health Care System, Geriatric Research, Educational and Clinical Center, Pittsburgh, PA, 15213, USA
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