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Wang Q, Liu T, Chang H, Li Z, Chen L, Mi X, Xing H, Wang X, Hong J, Liu K, Li Y, Han D, Li Y, Yang N, Li X, Li Y, Guo X. Low-Intensity Pulsed Ultrasound Attenuates Postoperative Neurocognitive Impairment and Salvages Hippocampal Synaptogenesis in Aged Mice. Brain Sci 2023; 13:brainsci13040657. [PMID: 37190622 DOI: 10.3390/brainsci13040657] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Revised: 04/07/2023] [Accepted: 04/12/2023] [Indexed: 05/17/2023] Open
Abstract
Postoperative neurocognitive impairment is an urgent problem with global aging accelerating. The prevention and treatment of postoperative neurocognitive impairment have been widely investigated but lack effective strategies. Low-intensity pulsed ultrasound (LIPUS), a non-invasive tool, has shown an effect on neuroprotection, but whether it could attenuate the postoperative neurocognitive impairment and the underlying mechanisms remains unknown. An experimental setup for LIPUS stimulation of the hippocampus was well established. A laparotomy model in aged mice was applied, and a Morris water maze was used to assess cognitive function. RT-qPCR and western blotting were used to detect levels of Piezo1, synapse-associated proteins in the hippocampus, respectively. Immunofluorescent staining was also used to determine the neural activation and Piezo1 expression. The results showed that LIPUS increased synapse-related proteins of the hippocampus and attenuated cognitive impairment in aged mice. Meanwhile, LIPUS suppressed the overexpression of Piezo1 in the hippocampus. We further found that LIPUS promoted Calpain1 activity and increased extracellular regulated protein kinases (Erk) phosphorylation. Our results suggested that LIPUS could improve cognitive impairment and increase hippocampal synaptogenesis through the Piezo1-mediated Calpain1/ Erk pathway. LIPUS could be used as an effective physical intervention to alleviate postoperative cognitive dysfunction in the aged population.
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Affiliation(s)
- Qian Wang
- Department of Anesthesiology, Peking University Third Hospital, Beijing 100191, China
| | - Taotao Liu
- Department of Anesthesiology, Peking University Third Hospital, Beijing 100191, China
| | - Huixian Chang
- School of Information Science and Engineering, Yanshan University, Qinhuangdao 066104, China
| | - Zhengqian Li
- Department of Anesthesiology, Peking University Third Hospital, Beijing 100191, China
- Beijing Center of Quality Control and Improvement on Clinical Anesthesia, Beijing 101300, China
| | - Lei Chen
- Department of Anesthesiology, Peking University Third Hospital, Beijing 100191, China
| | - Xinning Mi
- Department of Anesthesiology, Peking University Third Hospital, Beijing 100191, China
| | - Huayi Xing
- Department of Rehabilitation Medicine, Peking University Third Hospital, Beijing 100191, China
| | - Xiaoxiao Wang
- Research Center of Clinical Epidemiology, Peking University Third Hospital, Beijing 100191, China
| | - Jingshu Hong
- Department of Anesthesiology, Peking University Third Hospital, Beijing 100191, China
| | - Kaixi Liu
- Department of Anesthesiology, Peking University Third Hospital, Beijing 100191, China
| | - Yitong Li
- Department of Anesthesiology, Peking University Third Hospital, Beijing 100191, China
| | - Dengyang Han
- Department of Anesthesiology, Peking University Third Hospital, Beijing 100191, China
| | - Yue Li
- Department of Anesthesiology, Peking University Third Hospital, Beijing 100191, China
| | - Ning Yang
- Department of Anesthesiology, Peking University Third Hospital, Beijing 100191, China
| | - Xiaoli Li
- State Key Laboratory of Cognitive Neuroscience and Learning, Beijing Normal University, Beijing 100875, China
| | - Yingwei Li
- School of Information Science and Engineering, Yanshan University, Qinhuangdao 066104, China
| | - Xiangyang Guo
- Department of Anesthesiology, Peking University Third Hospital, Beijing 100191, China
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Emerging roles of PHLPP phosphatases in the nervous system. Mol Cell Neurosci 2022; 123:103789. [PMID: 36343848 DOI: 10.1016/j.mcn.2022.103789] [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: 08/30/2022] [Revised: 10/15/2022] [Accepted: 10/22/2022] [Indexed: 11/06/2022] Open
Abstract
It has been more than a decade since the discovery of a novel class of phosphatase, the Pleckstrin Homology (PH) domain Leucine-rich repeat Protein Phosphatases (PHLPP). Over time, they have been recognized as crucial regulators of various cellular processes, such as memory formation, cellular survival and proliferation, maintenance of circadian rhythm, and others, with any deregulation in their expression or cellular localization causing havoc in any cellular system. With the ever-growing number of downstream substrates across multiple tissue systems, a web is emerging wherein the central point is PHLPP. A slight nick in the normal signaling cascade of the two isoforms of PHLPP, namely PHLPP1 and PHLPP2, has been recently found to invoke a variety of neurological disorders including Alzheimer's disease, epileptic seizures, Parkinson's disease, and others, in the neuronal system. Improper regulation of the two isoforms has also been associated with various disease pathologies such as diabetes, cardiovascular disorders, cancer, musculoskeletal disorders, etc. In this review, we have summarized all the current knowledge about PHLPP1 (PHLPP1α and PHLPP1β) and PHLPP2 and their emerging roles in regulating various neuronal signaling pathways to pave the way for a better understanding of the complexities. This would in turn aid in providing context for the development of possible future therapeutic strategies.
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Chen SP, Hsu CL, Wang YF, Yang FC, Chen TH, Huang JH, Pan LLH, Fuh JL, Chang HC, Lee YL, Chang HC, Lee KH, Chang YC, Fann CSJ, Wang SJ. Genome-wide analyses identify novel risk loci for cluster headache in Han Chinese residing in Taiwan. J Headache Pain 2022; 23:147. [PMID: 36404298 PMCID: PMC9677903 DOI: 10.1186/s10194-022-01517-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Accepted: 10/21/2022] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND Cluster headache is a highly debilitating neurological disorder with considerable inter-ethnic differences. Genome-wide association studies (GWAS) recently identified replicable genomic loci for cluster headache in Europeans, but the genetic underpinnings for cluster headache in Asians remain unclear. The objective of this study is to investigate the genetic architecture and susceptibility loci of cluster headache in Han Chinese resided in Taiwan. METHODS We conducted a two-stage genome-wide association study in a Taiwanese cohort enrolled from 2007 through 2022 to identify the genetic variants associated with cluster headache. Diagnosis of cluster headache was retrospectively ascertained with the criteria of International Classification of Headache Disorders, third edition. Control subjects were enrolled from the Taiwan Biobank. Genotyping was conducted with the Axiom Genome-Wide Array TWB chip, followed by whole genome imputation. A polygenic risk score was developed to differentiate patients from controls. Downstream analyses including gene-set and tissue enrichment, linkage disequilibrium score regression, and pathway analyses were performed. RESULTS We enrolled 734 patients with cluster headache and 9,846 population-based controls. We identified three replicable loci, with the lead SNPs being rs1556780 in CAPN2 (odds ratio = 1.59, 95% CI 1.42‒1.78, p = 7.61 × 10-16), rs10188640 in MERTK (odds ratio = 1.52, 95% CI 1.33‒1.73, p = 8.58 × 10-13), and rs13028839 in STAB2 (odds ratio = 0.63, 95% CI 0.52‒0.78, p = 2.81 × 10-8), with the latter two replicating the findings in European populations. Several previously reported genes also showed significant associations with cluster headache in our samples. Polygenic risk score differentiated patients from controls with an area under the receiver operating characteristic curve of 0.77. Downstream analyses implicated circadian regulation and immunological processes in the pathogenesis of cluster headache. CONCLUSIONS This study revealed the genetic architecture and novel susceptible loci of cluster headache in Han Chinese residing in Taiwan. Our findings support the common genetic contributions of cluster headache across ethnicities and provide novel mechanistic insights into the pathogenesis of cluster headache.
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Affiliation(s)
- Shih-Pin Chen
- grid.278247.c0000 0004 0604 5314Department of Neurology, Neurological Institute, Taipei Veterans General Hospital, No. 201, Sec. 2, Shih-Pai Road, Taipei, 112 Taiwan ,grid.260539.b0000 0001 2059 7017Brain Research Center, National Yang Ming Chiao Tung University, Taipei, Taiwan ,grid.278247.c0000 0004 0604 5314Division of Translational Research, Department of Medical Research, Taipei Veterans General Hospital, Taipei, Taiwan ,grid.260539.b0000 0001 2059 7017Institute of Clinical Medicine, College of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan ,grid.260539.b0000 0001 2059 7017School of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Chia-Lin Hsu
- grid.28665.3f0000 0001 2287 1366Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Yen-Feng Wang
- grid.278247.c0000 0004 0604 5314Department of Neurology, Neurological Institute, Taipei Veterans General Hospital, No. 201, Sec. 2, Shih-Pai Road, Taipei, 112 Taiwan ,grid.260539.b0000 0001 2059 7017Brain Research Center, National Yang Ming Chiao Tung University, Taipei, Taiwan ,grid.260539.b0000 0001 2059 7017School of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Fu-Chi Yang
- grid.278244.f0000 0004 0638 9360Department of Neurology, Tri-Service General Hospital, Taipei, Taiwan
| | - Ting-Huei Chen
- grid.23856.3a0000 0004 1936 8390Department of Mathematics & Statistics, Laval University, Quebec City, QC Canada ,grid.23856.3a0000 0004 1936 8390Cervo Brain Research Centre, Quebec City, QC Canada
| | | | - Li-Ling Hope Pan
- grid.278247.c0000 0004 0604 5314Department of Neurology, Neurological Institute, Taipei Veterans General Hospital, No. 201, Sec. 2, Shih-Pai Road, Taipei, 112 Taiwan ,grid.260539.b0000 0001 2059 7017Brain Research Center, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Jong-Ling Fuh
- grid.278247.c0000 0004 0604 5314Department of Neurology, Neurological Institute, Taipei Veterans General Hospital, No. 201, Sec. 2, Shih-Pai Road, Taipei, 112 Taiwan ,grid.260539.b0000 0001 2059 7017Brain Research Center, National Yang Ming Chiao Tung University, Taipei, Taiwan ,grid.260539.b0000 0001 2059 7017School of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Hsueh-Chen Chang
- grid.278247.c0000 0004 0604 5314Department of Neurology, Neurological Institute, Taipei Veterans General Hospital, No. 201, Sec. 2, Shih-Pai Road, Taipei, 112 Taiwan ,grid.260539.b0000 0001 2059 7017Brain Research Center, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | | | | | | | | | - Cathy Shen-Jang Fann
- grid.28665.3f0000 0001 2287 1366Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Shuu-Jiun Wang
- grid.278247.c0000 0004 0604 5314Department of Neurology, Neurological Institute, Taipei Veterans General Hospital, No. 201, Sec. 2, Shih-Pai Road, Taipei, 112 Taiwan ,grid.260539.b0000 0001 2059 7017Brain Research Center, National Yang Ming Chiao Tung University, Taipei, Taiwan ,grid.260539.b0000 0001 2059 7017School of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan
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Balamurugan K, Chandra K, Sai Latha S, Swathi M, Joshi MB, Misra P, Parsa KVL. PHLPPs: Emerging players in metabolic disorders. Drug Discov Today 2022; 27:103317. [PMID: 35835313 DOI: 10.1016/j.drudis.2022.07.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Revised: 06/21/2022] [Accepted: 07/07/2022] [Indexed: 12/15/2022]
Abstract
That reversible protein phosphorylation by kinases and phosphatases occurs in metabolic disorders is well known. Various studies have revealed that a multi-faceted and tightly regulated phosphatase, pleckstrin homology domain leucine-rich repeat protein phosphatase (PHLPP)-1/2 displays robust effects in cardioprotection, ischaemia/reperfusion (I/R), and vascular remodelling. PHLPP1 promotes foamy macrophage development through ChREBP/AMPK-dependent pathways. Adipocyte-specific loss of PHLPP2 reduces adiposity, improves glucose tolerance,and attenuates fatty liver via the PHLPP2-HSL-PPARα axis. Discoveries of PHLPP1-mediated insulin resistance and pancreatic β cell death via the PHLPP1/2-Mst1-mTORC1 triangular loop have shed light on its significance in diabetology. PHLPP1 downregulation attenuates diabetic cardiomyopathy (DCM) by restoring PI3K-Akt-mTOR signalling. In this review, we summarise the functional role of, and cellular signalling mediated by, PHLPPs in metabolic tissues and discuss their potential as therapeutic targets.
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Affiliation(s)
- Keerthana Balamurugan
- Center for Innovation in Molecular and Pharmaceutical Sciences (CIMPS), Dr. Reddy's Institute of Life Sciences (DRILS), University of Hyderabad Campus, Hyderabad 500046, Telangana, India; Department of Ageing Research, Manipal School of Life Sciences, Manipal Academy of Higher Education (MAHE), Manipal 576104, Karnataka, India
| | - Kanika Chandra
- Center for Innovation in Molecular and Pharmaceutical Sciences (CIMPS), Dr. Reddy's Institute of Life Sciences (DRILS), University of Hyderabad Campus, Hyderabad 500046, Telangana, India; Department of Ageing Research, Manipal School of Life Sciences, Manipal Academy of Higher Education (MAHE), Manipal 576104, Karnataka, India
| | - S Sai Latha
- Center for Innovation in Molecular and Pharmaceutical Sciences (CIMPS), Dr. Reddy's Institute of Life Sciences (DRILS), University of Hyderabad Campus, Hyderabad 500046, Telangana, India
| | - M Swathi
- Center for Innovation in Molecular and Pharmaceutical Sciences (CIMPS), Dr. Reddy's Institute of Life Sciences (DRILS), University of Hyderabad Campus, Hyderabad 500046, Telangana, India
| | - Manjunath B Joshi
- Department of Ageing Research, Manipal School of Life Sciences, Manipal Academy of Higher Education (MAHE), Manipal 576104, Karnataka, India
| | - Parimal Misra
- Center for Innovation in Molecular and Pharmaceutical Sciences (CIMPS), Dr. Reddy's Institute of Life Sciences (DRILS), University of Hyderabad Campus, Hyderabad 500046, Telangana, India
| | - Kishore V L Parsa
- Center for Innovation in Molecular and Pharmaceutical Sciences (CIMPS), Dr. Reddy's Institute of Life Sciences (DRILS), University of Hyderabad Campus, Hyderabad 500046, Telangana, India.
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Hoyt KR, Obrietan K. Circadian clocks, cognition, and Alzheimer's disease: synaptic mechanisms, signaling effectors, and chronotherapeutics. Mol Neurodegener 2022; 17:35. [PMID: 35525980 PMCID: PMC9078023 DOI: 10.1186/s13024-022-00537-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Accepted: 04/08/2022] [Indexed: 12/20/2022] Open
Abstract
Modulation of basic biochemical and physiological processes by the circadian timing system is now recognized as a fundamental feature of all mammalian organ systems. Within the central nervous system, these clock-modulating effects are reflected in some of the most complex behavioral states including learning, memory, and mood. How the clock shapes these behavioral processes is only now beginning to be realized. In this review we describe recent findings regarding the complex set of cellular signaling events, including kinase pathways, gene networks, and synaptic circuits that are under the influence of the clock timing system and how this, in turn, shapes cognitive capacity over the circadian cycle. Further, we discuss the functional roles of the master circadian clock located in the suprachiasmatic nucleus, and peripheral oscillator populations within cortical and limbic circuits, in the gating of synaptic plasticity and memory over the circadian cycle. These findings are then used as the basis to discuss the connection between clock dysregulation and cognitive impairments resulting from Alzheimer's disease (AD). In addition, we discuss the conceptually novel idea that in AD, there is a selective disruption of circadian timing within cortical and limbic circuits, and that it is the disruption/desynchronization of these regions from the phase-entraining effects of the SCN that underlies aspects of the early- and mid-stage cognitive deficits in AD. Further, we discuss the prospect that the disruption of circadian timing in AD could produce a self-reinforcing feedback loop, where disruption of timing accelerates AD pathogenesis (e.g., amyloid deposition, oxidative stress and cell death) that in turn leads to a further disruption of the circadian timing system. Lastly, we address potential therapeutic approaches that could be used to strengthen cellular timing networks and, in turn, how these approaches could be used to improve cognitive capacity in Alzheimer's patients.
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Affiliation(s)
- Kari R Hoyt
- Division of Pharmaceutics and Pharmacology, Ohio State University, 412 Riffe Building, 12th Ave, Columbus, OH, 43210, USA.
| | - Karl Obrietan
- Department of Neuroscience, Ohio State University, Graves Hall, 333 W. 10th Ave, Columbus, OH, 43210, USA.
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Lemoine KA, Fassas JM, Ohannesian SH, Purcell NH. On the PHLPPside: Emerging roles of PHLPP phosphatases in the heart. Cell Signal 2021; 86:110097. [PMID: 34320369 PMCID: PMC8403656 DOI: 10.1016/j.cellsig.2021.110097] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Revised: 07/20/2021] [Accepted: 07/22/2021] [Indexed: 02/07/2023]
Abstract
PH domain leucine-rich repeat protein phosphatase (PHLPP) is a family of enzymes made up of two isoforms (PHLPP1 and PHLPP2), whose actions modulate intracellular activity via the dephosphorylation of specific serine/threonine (Ser/Thr) residues on proteins such as Akt. Recent data generated in our lab, supported by findings from others, implicates the divergent roles of PHLPP1 and PHLPP2 in maintaining cellular homeostasis since dysregulation of these enzymes has been linked to various pathological states including cardiovascular disease, diabetes, ischemia/reperfusion injury, musculoskeletal disease, and cancer. Therefore, development of therapies to modulate specific isoforms of PHLPP could prove to be therapeutically beneficial in several diseases especially those targeting the cardiovascular system. This review is intended to provide a comprehensive summary of current literature detailing the role of the PHLPP isoforms in the development and progression of heart disease.
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Affiliation(s)
- Kellie A Lemoine
- Department of Pharmacology, University of California, San Diego, La Jolla, CA 92039, USA
| | - Julianna M Fassas
- Department of Pharmacology, University of California, San Diego, La Jolla, CA 92039, USA
| | - Shirag H Ohannesian
- Department of Pharmacology, University of California, San Diego, La Jolla, CA 92039, USA
| | - Nicole H Purcell
- Department of Pharmacology, University of California, San Diego, La Jolla, CA 92039, USA; Cardiovascular Molecular Signaling, Huntington Medical Research Institutes, Pasadena, CA 91105, USA.
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Xing H, Fu R, Cheng C, Cai Y, Wang X, Deng D, Gong X, Chen J. Hyperoside Protected Against Oxidative Stress-Induced Liver Injury via the PHLPP2-AKT-GSK-3β Signaling Pathway In Vivo and In Vitro. Front Pharmacol 2020; 11:1065. [PMID: 32765271 PMCID: PMC7379337 DOI: 10.3389/fphar.2020.01065] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Accepted: 06/30/2020] [Indexed: 12/19/2022] Open
Abstract
Hyperoside, isolated from Drosera rotundifolia L., seeds of Cuscuta chinensis Lam., or Hypericum perforatum L., originally showed to possess an antifungal and antibacterial activity, while recently showed the protective effects against oxidative stress-induced liver injury. This study investigated such a protective effect of hyperoside and the underlying molecular mechanisms in vitro and in carbon tetrachloride (CCl4)-injured rat livers. The data showed that hyperoside was able to prevent the oxidative stress-induced liver morphological changes and CCl4-induced rat liver injury. Hyperoside reversed the decrease of superoxidase dismutase (SOD) level and the increase of malondialdehyde (MDA) level in vivo. Moreover, hyperoside regulated the pleckstrin homology (PH) domain leucine-rich repeat protein phosphatase 2 (PHLPP2)-protein kinase B (AKT)-glycogen synthase kinase 3β (GSK-3β) signaling pathway in tert-butylhydroquinone (t-BHP)-treated liver cells, e.g., Hyperoside reduced PHLPP2 expression to activate AKT phosphorylation, induce GSK-3β phosphorylation, and then increased nuclear factor erythroid-2-related factor 2 (Nrf2) nuclear translocation, reduced nuclear translocation of phosphorylated Fyn, and promoted heme oxygenase-1 (HO-1) expression in vivo and in vitro. In contrast, siRNA-mediated knockdown of PHLPP2 expression enhanced hyperoside-mediated activation of the AKT-GSK-3β kinase pathway in liver cells. In conclusion, the present study demonstrated that hyperoside could protect against oxidative stress-induced liver injury by regulating the PHLPP2-AKT-GSK-3β signaling pathway in vivo and in vitro.
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Affiliation(s)
- Haiyan Xing
- Department of Pharmacy, Daping Hospital, Army Medical University, Chongqing, China
| | - Ruoqiu Fu
- Department of Pharmacy, Daping Hospital, Army Medical University, Chongqing, China
| | - Caiyi Cheng
- Department of Pharmacy, Daping Hospital, Army Medical University, Chongqing, China
| | - Yongqing Cai
- Department of Pharmacy, Daping Hospital, Army Medical University, Chongqing, China
| | - Xianfeng Wang
- Department of Pharmacy, Daping Hospital, Army Medical University, Chongqing, China
| | - Dongmei Deng
- Department of Pharmacy, Daping Hospital, Army Medical University, Chongqing, China
| | - Xiaoyuan Gong
- Center for Joint Surgery, Southwest Hospital, Army Medical University, Chongqing, China
| | - Jianhong Chen
- Department of Pharmacy, Daping Hospital, Army Medical University, Chongqing, China
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Song ZJ, Yang SJ, Han L, Wang B, Zhu G. Postnatal calpeptin treatment causes hippocampal neurodevelopmental defects in neonatal rats. Neural Regen Res 2019; 14:834-840. [PMID: 30688269 PMCID: PMC6375038 DOI: 10.4103/1673-5374.249231] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Our previous studies showed that the early use of calpain inhibitors reduces calpain activity in multiple brain regions, and that postnatal treatment with calpeptin may lead to cerebellar motor dysfunction. However, it remains unclear whether postnatal calpeptin application affects hippocampus-related behaviors. In this study, Sprague-Dawley rats were purchased from the Animal Center of Anhui Medical University of China. For the experiments in the adult stage, rats were intraperitoneally injected with calpeptin, 2 mg/kg, once a day, on postnatal days 7-14. Then on postnatal day 60, the Morris water maze test was used to evaluate spatial learning and memory abilities. The open field test was carried out to assess anxiety-like activities. Phalloidin staining was performed to observe synaptic morphology in the hippocampus. Immunohistochemistry was used to count the number of NeuN-positive cells in the hippocampal CA1 region. DiI was applied to label dendritic spines. Calpeptin administration impaired spatial memory, caused anxiety-like behavior in adulthood, reduced the number and area of apical dendritic spines, and decreased actin polymerization in the hippocampus, but did not affect the number of NeuN-positive cells in the hippocampal CA1 region. For the neonatal experiments, neonatal rats were intraperitoneally injected with calpeptin, 2 mg/kg, on postnatal days 7 and 8. Western blot assay was performed to analyze the protein levels of Akt, Erk, p-Akt, p-Erk1/2, Erk1/2, SCOP, PTEN, mTOR, p-mTOR, CREB and p-CREB in the hippocampus. SCOP expression was increased, and the phosphorylation levels of Akt, mTOR and CREB were reduced in the hippocampus. These findings show that calpeptin administration after birth affects synaptic development in neonatal rats by inhibiting the Akt/mTOR signaling pathway, thereby perturbing hippocampal function. Therefore, calpeptin administration after birth is a risk factor for neurodevelopmental defects.
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Affiliation(s)
- Zhu-Jin Song
- Key Laboratory of Xin'an Medicine, Ministry of Education, Anhui University of Chinese Medicine, Hefei, Anhui Province, China
| | - San-Juan Yang
- Key Laboratory of Xin'an Medicine, Ministry of Education, Anhui University of Chinese Medicine, Hefei, Anhui Province, China
| | - Lan Han
- School of Pharmacy, Anhui University of Chinese Medicine, Hefei, Anhui Province, China
| | - Bin Wang
- Key Laboratory of Xin'an Medicine, Ministry of Education, Anhui University of Chinese Medicine, Hefei, Anhui Province, China
| | - Guoqi Zhu
- Key Laboratory of Xin'an Medicine, Ministry of Education, Anhui University of Chinese Medicine, Hefei, Anhui Province, China
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Song Z, Chen H, Xu W, Wu S, Zhu G. Basolateral amygdala calpain is required for extinction of contextual fear-memory. Neurobiol Learn Mem 2018; 155:180-188. [PMID: 30086394 DOI: 10.1016/j.nlm.2018.08.004] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Revised: 06/25/2018] [Accepted: 08/03/2018] [Indexed: 02/07/2023]
Abstract
Extinction of fear-memory is essential for emotional and mental changes. However, the mechanisms underlying extinction of fear-memory are largely unknown. Calpain is a type of calcium-dependent protease that plays a critical role in memory consolidation and reconsolidation. Whether calpain functions in extinction of fear-memory is unknown, as are the molecular mechanisms. In this study, we investigated the pivotal role of calpain in extinction of fear-memory in mice, and assessed its mechanism. Conditioned stimulation/unconditioned stimulation-conditioned stimulation paradigms combined with pharmacological methods were employed to evaluate the action of calpain in memory extinction. Our data demonstrated that intraperitoneal or intra-basolateral amygdala (BLA) injection of calpain inhibitors could eliminate extinction of fear-memory in mice. Moreover, extinction of fear-memory paradigm-activated BLA calpain activity, which degraded suprachiasmatic nucleus circadian oscillatory protein (SCOP) and phosphatase and tensin homolog (PTEN), subsequently contributing to activation of a protein kinase B (AKT)-mammalian target of the rapamycin (mTor) signaling pathway. Additionally, cAMP-response element binding protein (CREB) phosphorylation was also augmented following extinction of fear-memory. Calpain inhibitor blocked the signaling pathway activation induced by extinction of fear-memory. Additionally, intra-BLA injection of rapamycin or cycloheximide also blocked the extinction of fear-memory. Conversely, intra-BLA injection of PTEN inhibitor, bpV, reversed the effect of calpeptin on extinction of fear-memory. Together, our data confirmed the function of BLA calpain in extinction of fear-memory, likely via degrading PTEN and activating AKT-mTor-dependent protein synthesis.
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Affiliation(s)
- Zhujin Song
- Key Laboratory of Xin'an Medicine, Ministry of Education, Anhui University of Chinese Medicine, Hefei 230038, China
| | - Hui Chen
- Key Laboratory of Xin'an Medicine, Ministry of Education, Anhui University of Chinese Medicine, Hefei 230038, China
| | - Wen Xu
- Department of Neurology, The first Affiliated Hospital of University of Science and Technology of China, Anhui Provincial Hospital, Hefei 230001, China
| | - Shengbing Wu
- Key Laboratory of Xin'an Medicine, Ministry of Education, Anhui University of Chinese Medicine, Hefei 230038, China; Anhui Academy of Chinese Medicine, Hefei 230038, China
| | - Guoqi Zhu
- Key Laboratory of Xin'an Medicine, Ministry of Education, Anhui University of Chinese Medicine, Hefei 230038, China; Anhui Academy of Chinese Medicine, Hefei 230038, China.
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Circadian Regulation of Hippocampal-Dependent Memory: Circuits, Synapses, and Molecular Mechanisms. Neural Plast 2018; 2018:7292540. [PMID: 29593785 PMCID: PMC5822921 DOI: 10.1155/2018/7292540] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2017] [Accepted: 12/18/2017] [Indexed: 01/01/2023] Open
Abstract
Circadian modulation of learning and memory efficiency is an evolutionarily conserved phenomenon, occurring in organisms ranging from invertebrates to higher mammalian species, including humans. While the suprachiasmatic nucleus (SCN) of the hypothalamus functions as the master mammalian pacemaker, recent evidence suggests that forebrain regions, including the hippocampus, exhibit oscillatory capacity. This finding, as well as work on the cellular signaling events that underlie learning and memory, has opened promising new avenues of investigation into the precise cellular, molecular, and circuit-based mechanisms by which clock timing impacts plasticity and cognition. In this review, we examine the complex molecular relationship between clock timing and memory, with a focus on hippocampal-dependent tasks. We evaluate how the dysregulation of circadian timing, both at the level of the SCN and at the level of ancillary forebrain clocks, affects learning and memory. Further, we discuss experimentally validated intracellular signaling pathways (e.g., ERK/MAPK and GSK3β) and potential cellular signaling mechanisms by which the clock affects learning and memory formation. Finally, we examine how long-term potentiation (LTP), a synaptic process critical to the establishment of several forms of memory, is regulated by clock-gated processes.
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Mathur A, Pandey VK, Kakkar P. PHLPP: a putative cellular target during insulin resistance and type 2 diabetes. J Endocrinol 2017; 233:R185-R198. [PMID: 28428363 DOI: 10.1530/joe-17-0081] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/22/2017] [Accepted: 04/20/2017] [Indexed: 12/29/2022]
Abstract
Progressive research in the past decade converges to the impact of PHLPP in regulating the cellular metabolism through PI3K/AKT inhibition. Aberrations in PKB/AKT signaling coordinates with impaired insulin secretion and insulin resistance, identified during T2D, obesity and cardiovascular disorders which brings in the relevance of PHLPPs in the metabolic paradigm. In this review, we discuss the impact of PHLPP isoforms in insulin signaling and its associated cellular events including mitochondrial dysfunction, DNA damage, autophagy and cell death. The article highlights the plausible molecular targets that share the role during insulin-resistant states, whose understanding can be extended into treatment responses to facilitate targeted drug discovery for T2D and allied metabolic syndromes.
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Affiliation(s)
- Alpana Mathur
- Herbal Research LaboratoryCSIR-Indian Institute of Toxicology Research, Lucknow, India
- Babu Banarasi Das UniversityBBD City, Lucknow, India
| | - Vivek Kumar Pandey
- Herbal Research LaboratoryCSIR-Indian Institute of Toxicology Research, Lucknow, India
- Academy of Scientific and Innovative ResearchCSIR-IITR, Lucknow, India
| | - Poonam Kakkar
- Herbal Research LaboratoryCSIR-Indian Institute of Toxicology Research, Lucknow, India
- Babu Banarasi Das UniversityBBD City, Lucknow, India
- Academy of Scientific and Innovative ResearchCSIR-IITR, Lucknow, India
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12
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Ding L, Zhang S, Xu M, Zhang R, Sui P, Yang Q. MicroRNA-27a contributes to the malignant behavior of gastric cancer cells by directly targeting PH domain and leucine-rich repeat protein phosphatase 2. JOURNAL OF EXPERIMENTAL & CLINICAL CANCER RESEARCH : CR 2017; 36:45. [PMID: 28327189 PMCID: PMC5361803 DOI: 10.1186/s13046-017-0516-2] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Accepted: 03/16/2017] [Indexed: 12/23/2022]
Abstract
Background Accumulating evidence indicates that microRNA-27a (miR-27a) is involved in carcinogenesis and tumor progression. However, the exact function and molecular mechanism of miR-27a in gastric cancer remain unclear. Methods Quantitative real-time PCR (qRT-PCR) was used to quantify the expression of miR-27a and its target gene. The function of miR-27a in gastric cancer was investigated through in vitro and in vivo assays (MTT assay, colony formation assay, flow cytometry assay, wound healing assay, migration and invasion assay, immunohistochemistry (IHC), immunofluorescence (IF) and Western blot). A luciferase reporter assay was conducted to confirm the target gene of miR-27a. Results We found that miR-27a was commonly overexpressed in gastric cancer and high expression of miR-27a was associated with distant metastasis, lymph node metastasis, advanced T stage and advanced clinical stage. Functional assays demonstrated that overexpression of miR-27a in AGS cells accelerated cell proliferation, migration and invasion and suppressed apoptosis. Meanwhile, opposite results were observed in SGC-7901 cells when miR-27a was suppressed. Consistently, down-regulation of miR-27a inhibited the growth and metastasis of engrafted tumors in vivo. Furthermore, we found PH domain and leucine-rich repeat protein phosphatase 2 (PHLPP2) to be a new target of miR-27a, and downregulation of PHLPP2 could rescue the effect of anti-miR-27a in gastric cancer cells. In addition, miR-27a-mediated suppression of PHLPP2 led to stimulation of the AKT/GSK3β pathway. Conclusions Our data suggest that miR-27a functions as a crucial oncogenic miRNA in gastric cancer. It can promote proliferation and metastasis of tumor cells by suppressing PHLPP2 and activating the AKT/GSK3β pathway. Therefore, miR-27a is a potential novel therapeutic target in gastric cancer treatment. Electronic supplementary material The online version of this article (doi:10.1186/s13046-017-0516-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Lei Ding
- Department of Pathogenobiology, College of Basic Medical Sciences, Jilin University, 126 Xinmin Street, Changchun, 130021, Jilin Province, China
| | - Shanyong Zhang
- Department of Orthopedics, The Second Hospital, Jilin University, Changchun, Jilin, China
| | - Mu Xu
- Department of Pathogenobiology, College of Basic Medical Sciences, Jilin University, 126 Xinmin Street, Changchun, 130021, Jilin Province, China
| | - Renwen Zhang
- Department of Pathogenobiology, College of Basic Medical Sciences, Jilin University, 126 Xinmin Street, Changchun, 130021, Jilin Province, China
| | - Pengcheng Sui
- Department of Pathogenobiology, College of Basic Medical Sciences, Jilin University, 126 Xinmin Street, Changchun, 130021, Jilin Province, China
| | - Qing Yang
- Department of Pathogenobiology, College of Basic Medical Sciences, Jilin University, 126 Xinmin Street, Changchun, 130021, Jilin Province, China.
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Nakano JJ, Shimizu K, Shimba S, Fukada Y. SCOP/PHLPP1β in the basolateral amygdala regulates circadian expression of mouse anxiety-like behavior. Sci Rep 2016; 6:33500. [PMID: 27640726 PMCID: PMC5027591 DOI: 10.1038/srep33500] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Accepted: 08/26/2016] [Indexed: 12/16/2022] Open
Abstract
While disruption of the circadian clock triggers a spectrum of affective abnormalities, how the clock regulates mammalian emotionality remains unclear. Here, we characterized the time-of-day-dependent regulation of mouse anxiety-like behaviors. We show that anxiety-like behaviors are expressed in a circadian manner in mice and demonstrate that the clock machineries in the dorsal telencephalon (dTel) are required for the time-of-day-dependent regulation of anxiety-like behaviors. We identify suprachiasmatic nucleus circadian oscillatory protein (SCOP/PHLPP1β) as an essential intracellular signaling molecule mediating this temporal regulation downstream of the clock. Using viral-mediated, basolateral amygdala (BLA)-specific knockout of Scop, we demonstrate that deletion of SCOP in the BLA exerts anxiolytic effects on the elevated plus maze at early subjective night, thereby blunting the circadian variation in the anxiety-like behavior. We conclude that the circadian expression of SCOP in the BLA plays a key role in generating circadian rhythmicity in the anxiety-like behavior. Our results demonstrate SCOP as a regulator of anxiety-like behaviors and reveal its key roles in the anxiogenic functions of the BLA.
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Affiliation(s)
- Jun J Nakano
- Department of Biological Sciences, School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Kimiko Shimizu
- Department of Biological Sciences, School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Shigeki Shimba
- Department of Health Science, School of Pharmacy, Nihon University, 7-7-1, Narashinodai, Funabashi-shi, Chiba 274-8555, Japan
| | - Yoshitaka Fukada
- Department of Biological Sciences, School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
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Liu Y, Sun J, Wang Y, Lopez D, Tran J, Bi X, Baudry M. Deleting both PHLPP1 and CANP1 rescues impairments in long-term potentiation and learning in both single knockout mice. ACTA ACUST UNITED AC 2016; 23:399-404. [PMID: 27421891 PMCID: PMC4947237 DOI: 10.1101/lm.042721.116] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2016] [Accepted: 05/18/2016] [Indexed: 11/25/2022]
Abstract
Calpain-1 (CANP1) has been shown to play a critical role in synaptic plasticity and learning and memory, as its deletion in mice results in impairment in theta-burst stimulation- (TBS) induced LTP and various forms of learning and memory. Likewise, PHLPP1 (aka SCOP) has also been found to participate in learning and memory, as PHLPP1 overexpression impairs hippocampus-dependent learning. We previously showed that TBS-induced LTP was associated with calpain-1 mediated truncation of PHLPP1.To better understand the roles of these 2 genes in synaptic plasticity and learning and memory, we generated a double knockout (DKO) mouse by crossing the parent strains. Surprisingly, DKO mice exhibit normal TBS-induced LTP, and the learning impairments in fear conditioning and novel object or novel location recognition were absent in the DKO mice. Moreover, TBS-induced ERK activation in field CA1 of hippocampal slices, which is impaired in both single deletion mice, was restored in the DKO mice. These results further strengthen the roles of both CANP1 and PHLPP1 in synaptic plasticity and learning and memory, and illustrate the complexities of the interactions between multiple pathways participating in synaptic plasticity.
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Affiliation(s)
- Yan Liu
- Graduate College of Biomedical Sciences, Western University of Health Sciences, Pomona, California 91766, USA
| | - Jiandong Sun
- College of Osteopathic Medicine of the Pacific, Western University of Health Sciences, Pomona, California 91766, USA
| | - Yubin Wang
- Graduate College of Biomedical Sciences, Western University of Health Sciences, Pomona, California 91766, USA
| | - Dulce Lopez
- Graduate College of Biomedical Sciences, Western University of Health Sciences, Pomona, California 91766, USA
| | - Jennifer Tran
- Graduate College of Biomedical Sciences, Western University of Health Sciences, Pomona, California 91766, USA College of Osteopathic Medicine of the Pacific, Western University of Health Sciences, Pomona, California 91766, USA
| | - Xiaoning Bi
- College of Osteopathic Medicine of the Pacific, Western University of Health Sciences, Pomona, California 91766, USA
| | - Michel Baudry
- Graduate College of Biomedical Sciences, Western University of Health Sciences, Pomona, California 91766, USA
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Krishnan HC, Lyons LC. Synchrony and desynchrony in circadian clocks: impacts on learning and memory. ACTA ACUST UNITED AC 2015; 22:426-37. [PMID: 26286653 PMCID: PMC4561405 DOI: 10.1101/lm.038877.115] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2015] [Accepted: 06/29/2015] [Indexed: 12/11/2022]
Abstract
Circadian clocks evolved under conditions of environmental variation, primarily alternating light dark cycles, to enable organisms to anticipate daily environmental events and coordinate metabolic, physiological, and behavioral activities. However, modern lifestyle and advances in technology have increased the percentage of individuals working in phases misaligned with natural circadian activity rhythms. Endogenous circadian oscillators modulate alertness, the acquisition of learning, memory formation, and the recall of memory with examples of circadian modulation of memory observed across phyla from invertebrates to humans. Cognitive performance and memory are significantly diminished when occurring out of phase with natural circadian rhythms. Disruptions in circadian regulation can lead to impairment in the formation of memories and manifestation of other cognitive deficits. This review explores the types of interactions through which the circadian clock modulates cognition, highlights recent progress in identifying mechanistic interactions between the circadian system and the processes involved in memory formation, and outlines methods used to remediate circadian perturbations and reinforce circadian adaptation.
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Affiliation(s)
- Harini C Krishnan
- Department of Biological Science, Program in Neuroscience, Florida State University, Tallahassee, Florida 32306, USA
| | - Lisa C Lyons
- Department of Biological Science, Program in Neuroscience, Florida State University, Tallahassee, Florida 32306, USA
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Abstract
Precise control of the balance between protein phosphorylation, catalyzed by protein kinases, and protein dephosphorylation, catalyzed by protein phosphatases, is essential for cellular homeostasis. Dysregulation of this balance leads to pathophysiological states, driving diseases such as cancer, heart disease, and diabetes. Aberrant phosphorylation of components of the pathways that control cell growth and cell survival are particularly prevalent in cancer. One of the most studied tumor suppressors in these pathways is the lipid phosphatase PTEN (phosphatase and tensin homolog deleted on chromosome ten), which dephosphorylates the lipid second messenger phosphatidylinositol 3,4,5-trisphosphate (PIP3), thus preventing activation of the oncogenic kinase AKT (v-akt murine thymoma viral oncogene homolog). In 2005, the discovery of a family of protein phosphatases whose members directly dephosphorylate and inactivate AKT introduced a new negative regulator of the phosphoinositide 3-kinase (PI3K) oncogenic pathway. Pleckstrin homology domain leucine-rich repeat protein phosphatase (PHLPP) isozymes comprise a novel tumor suppressor family whose two members, PHLPP1 and PHLPP2, are deleted as frequently as PTEN in cancers such as those of the prostate. PHLPP is thus a novel therapeutic target to suppress oncogenic pathways and is a potential candidate biomarker to stratify patients for the appropriate targeted therapeutics. This review discusses the role of PHLPP in terminating AKT signaling and how pharmacological intervention would impact this pathway.
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Affiliation(s)
- Alexandra C Newton
- Department of Pharmacology, University of California, San Diego, La Jolla, California 92093;
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Gangula NR, Maddika S. WD repeat protein WDR48 in complex with deubiquitinase USP12 suppresses Akt-dependent cell survival signaling by stabilizing PH domain leucine-rich repeat protein phosphatase 1 (PHLPP1). J Biol Chem 2013; 288:34545-54. [PMID: 24145035 PMCID: PMC3843068 DOI: 10.1074/jbc.m113.503383] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
PHLPP1 (PH domain leucine-rich repeat protein phosphatase 1) is a protein-serine/threonine phosphatase and a negative regulator of the PI3-kinase/Akt pathway. Although its function as a suppressor of tumor cell growth has been established, the mechanism of its regulation is not completely understood. In this study, by utilizing the tandem affinity purification approach we have identified WDR48 and USP12 as novel PHLPP1-associated proteins. The WDR48·USP12 complex deubiquitinates PHLPP1 and thereby enhances its protein stability. Similar to PHLPP1 function, WDR48 and USP12 negatively regulate Akt activation and thus promote cellular apoptosis. Functionally, we show that WDR48 and USP12 suppress proliferation of tumor cells. Importantly, we found a WDR48 somatic mutation (L580F) that is defective in stabilizing PHLPP1 in colorectal cancers, supporting a WDR48 role in tumor suppression. Together, our results reveal WDR48 and USP12 as novel PHLPP1 regulators and potential suppressors of tumor cell survival.
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Affiliation(s)
- Narmadha Reddy Gangula
- From the Laboratory of Cell Death and Cell Survival, Centre for DNA Fingerprinting and Diagnostics (CDFD), Nampally, Hyderabad 500001, India
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18
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Downregulation of PHLPP expression contributes to hypoxia-induced resistance to chemotherapy in colon cancer cells. Mol Cell Biol 2013; 33:4594-605. [PMID: 24061475 DOI: 10.1128/mcb.00695-13] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Hypoxia is a feature of solid tumors. Most tumors are at least partially hypoxic. This hypoxic environment plays a critical role in promoting resistance to anticancer drugs. PHLPP, a novel family of Ser/Thr protein phosphatases, functions as a tumor suppressor in colon cancers. Here, we show that the expression of both PHLPP isoforms is negatively regulated by hypoxia/anoxia in colon cancer cells. Interestingly, a hypoxia-induced decrease of PHLPP expression is attenuated by knocking down HIF1α but not HIF2α. Whereas the mRNA levels of PHLPP are not significantly altered by oxygen deprivation, the reduction of PHLPP expression is caused by decreased protein translation downstream of mTOR and increased degradation. Specifically, hypoxia-induced downregulation of PHLPP is partially rescued in TSC2 or 4E-BP1 knockdown cells as the result of elevated mTOR activity and protein synthesis. Moreover, oxygen deprivation destabilizes PHLPP protein by decreasing the expression of USP46, a deubiquitinase of PHLPP. Functionally, downregulation of PHLPP contributes to hypoxia-induced chemoresistance in colon cancer cells. Taken together, we have identified hypoxia as a novel mechanism by which PHLPP is downregulated in colon cancer, and the expression of PHLPP may serve as a biomarker for better understanding of chemoresistance in cancer treatment.
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Wang Z, Shu H, Wang Z, Li G, Cui J, Wu H, Cai S, He W, He Y, Zhan W. Loss expression of PHLPP1 correlates with lymph node metastasis and exhibits a poor prognosis in patients with gastric cancer. J Surg Oncol 2013; 108:427-32. [PMID: 24037758 DOI: 10.1002/jso.23419] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2013] [Accepted: 07/31/2013] [Indexed: 01/02/2023]
Affiliation(s)
- Zhixiong Wang
- Department of Gastrointestinal Surgery and Centre of Gastric Cancer; First Affiliated Hospital of Sun Yat-sen University; Guangzhou Guangdong Province People's Republic of China
| | - Haihua Shu
- Department of Anesthesiology; First Affiliated Hospital of Sun Yat-sen University; Guangzhou Guangdong Province People's Republic of China
| | - Zhao Wang
- Department of Gastrointestinal Surgery and Centre of Gastric Cancer; First Affiliated Hospital of Sun Yat-sen University; Guangzhou Guangdong Province People's Republic of China
| | - Guanghua Li
- Department of Gastrointestinal Surgery and Centre of Gastric Cancer; First Affiliated Hospital of Sun Yat-sen University; Guangzhou Guangdong Province People's Republic of China
| | - Ji Cui
- Department of Gastrointestinal Surgery and Centre of Gastric Cancer; First Affiliated Hospital of Sun Yat-sen University; Guangzhou Guangdong Province People's Republic of China
| | - Hui Wu
- Department of Gastrointestinal Surgery and Centre of Gastric Cancer; First Affiliated Hospital of Sun Yat-sen University; Guangzhou Guangdong Province People's Republic of China
| | - Shirong Cai
- Department of Gastrointestinal Surgery and Centre of Gastric Cancer; First Affiliated Hospital of Sun Yat-sen University; Guangzhou Guangdong Province People's Republic of China
| | - Weiling He
- Department of Gastrointestinal Surgery and Centre of Gastric Cancer; First Affiliated Hospital of Sun Yat-sen University; Guangzhou Guangdong Province People's Republic of China
| | - Yulong He
- Department of Gastrointestinal Surgery and Centre of Gastric Cancer; First Affiliated Hospital of Sun Yat-sen University; Guangzhou Guangdong Province People's Republic of China
| | - Wenhua Zhan
- Department of Gastrointestinal Surgery and Centre of Gastric Cancer; First Affiliated Hospital of Sun Yat-sen University; Guangzhou Guangdong Province People's Republic of China
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20
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Liao WT, Li TT, Wang ZG, Wang SY, He MR, Ye YP, Qi L, Cui YM, Wu P, Jiao HL, Zhang C, Xie YJ, Wang JX, Ding YQ. microRNA-224 promotes cell proliferation and tumor growth in human colorectal cancer by repressing PHLPP1 and PHLPP2. Clin Cancer Res 2013; 19:4662-72. [PMID: 23846336 DOI: 10.1158/1078-0432.ccr-13-0244] [Citation(s) in RCA: 101] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
PURPOSE To investigate the clinicopathologic significance, role, and mechanism of action of microRNA-224 (miR-224) in colorectal cancer. EXPERIMENTAL DESIGN Real-time PCR was used to quantify miR-224 expression. The association of miR-224 with the clinicopathologic features and survival was evaluated in 110 colorectal cancer patients. The role of miR-224 in colorectal cancer was investigated using in vitro and in vivo assays. Luciferase reporter assays were conducted to confirm target gene associations. RESULTS miR-224 was overexpressed in colorectal cancer. High-level expression of miR-224 was significantly associated with an aggressive phenotype and poor prognosis. Overexpression of miR-224 promoted colorectal cancer cell proliferation in vitro and tumor growth in vivo. Specifically, miR-224 accelerated the G1-S phase transition through activation of AKT/FOXO3a signaling, downregulation of p21Cip1 and p27Kip1, and upregulation of cyclin D1. Moreover, both PH domain leucine-rich-repeats protein phosphatase 1 (PHLPP1) and PHLPP2, antagonists of PI3K/AKT signaling, were confirmed as bona fide targets of miR-224. miR-224 directly targeted the 3'-untranslated regions of the PHLPP1 and PHLPP2 mRNAs and repressed their expression. CONCLUSION This study reveals functional and mechanistic links between miRNA-224 and the tumor suppressors PHLPP1 and PHLPP2 in the pathogenesis of colorectal cancer. miR-224 not only plays important roles in the regulation of cell proliferation and tumor growth in colorectal cancer, but also has potential as a prognostic marker or therapeutic target for colorectal cancer.
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Affiliation(s)
- Wen-Ting Liao
- Department of Pathology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China
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Li X, Stevens PD, Yang H, Gulhati P, Wang W, Evers BM, Gao T. The deubiquitination enzyme USP46 functions as a tumor suppressor by controlling PHLPP-dependent attenuation of Akt signaling in colon cancer. Oncogene 2012; 32:471-8. [PMID: 22391563 PMCID: PMC3371166 DOI: 10.1038/onc.2012.66] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
PHLPP is a family of Ser/Thr protein phosphatases that serve as tumor suppressors by negatively regulating Akt. Our recent studies have demonstrated that the ubiquitin proteasome pathway plays an important role in the downregulation of PHLPP in colorectal cancer. In this study, we show that the deubiquitinase USP46 stabilizes the expression of both PHLPP isoforms by reducing the rate of PHLPP degradation. USP46 binds to PHLPP and directly removes the polyubiquitin chains from PHLPP in vitro and in cells. Increased USP46 expression correlates with decreased ubiquitination and upregulation of PHLPP proteins in colon cancer cells, whereas knockdown of USP46 has the opposite effect. Functionally, USP46-mediated stabilization of PHLPP and the subsequent inhibition of Akt result in a decrease in cell proliferation and tumorigenesis of colon cancer cells in vivo. Moreover, reduced USP46 protein level is found associated with poor PHLPP expression in colorectal cancer patient specimens. Taken together, these results indentify a tumor suppressor role of USP46 in promoting PHLPP expression and inhibiting Akt signaling in colon cancer.
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Affiliation(s)
- X Li
- Markey Cancer Center, University of Kentucky, Lexington, KY, USA
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22
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Chen M, Pratt CP, Zeeman ME, Schultz N, Taylor BS, O’Neill A, Castillo-Martin M, Nowak DG, Naguib A, Grace DM, Murn J, Navin N, Atwal GS, Sander C, Gerald WL, Cordon-Cardo C, Newton AC, Carver BS, Trotman LC. Identification of PHLPP1 as a tumor suppressor reveals the role of feedback activation in PTEN-mutant prostate cancer progression. Cancer Cell 2011; 20:173-86. [PMID: 21840483 PMCID: PMC3176728 DOI: 10.1016/j.ccr.2011.07.013] [Citation(s) in RCA: 131] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/06/2011] [Revised: 06/05/2011] [Accepted: 07/27/2011] [Indexed: 01/04/2023]
Abstract
Hyperactivation of the PI 3-kinase/AKT pathway is a driving force of many cancers. Here we identify the AKT-inactivating phosphatase PHLPP1 as a prostate tumor suppressor. We show that Phlpp1-loss causes neoplasia and, on partial Pten-loss, carcinoma in mouse prostate. This genetic setting initially triggers a growth suppressive response via p53 and the Phlpp2 ortholog, and reveals spontaneous Trp53 inactivation as a condition for full-blown disease. Surprisingly, the codeletion of PTEN and PHLPP1 in patient samples is highly restricted to metastatic disease and tightly correlated to deletion of TP53 and PHLPP2. These data establish a conceptual framework for progression of PTEN mutant prostate cancer to life-threatening disease.
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Affiliation(s)
- Muhan Chen
- Cold Spring Harbor Laboratory, One Bungtown Road, Cold Spring Harbor, New York 11724, USA
| | - Christopher P. Pratt
- Cold Spring Harbor Laboratory, One Bungtown Road, Cold Spring Harbor, New York 11724, USA
| | - Martha E. Zeeman
- Cold Spring Harbor Laboratory, One Bungtown Road, Cold Spring Harbor, New York 11724, USA
| | - Nikolaus Schultz
- Computational Biology Program, Memorial Sloan-Kettering Cancer Center, New York, New York 10021, USA
| | - Barry S. Taylor
- Computational Biology Program, Memorial Sloan-Kettering Cancer Center, New York, New York 10021, USA
| | - Audrey O’Neill
- Department of Pharmacology, University of California San Diego, La Jolla, California 92093, USA
| | | | - Dawid G. Nowak
- Cold Spring Harbor Laboratory, One Bungtown Road, Cold Spring Harbor, New York 11724, USA
| | - Adam Naguib
- Cold Spring Harbor Laboratory, One Bungtown Road, Cold Spring Harbor, New York 11724, USA
| | - Danielle M. Grace
- Cold Spring Harbor Laboratory, One Bungtown Road, Cold Spring Harbor, New York 11724, USA
| | - Jernej Murn
- Cold Spring Harbor Laboratory, One Bungtown Road, Cold Spring Harbor, New York 11724, USA
| | - Nick Navin
- Department of Genetics, Department of Bioinformatics and Computational Biology, MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Gurinder S. Atwal
- Cold Spring Harbor Laboratory, One Bungtown Road, Cold Spring Harbor, New York 11724, USA
| | - Chris Sander
- Computational Biology Program, Memorial Sloan-Kettering Cancer Center, New York, New York 10021, USA
| | - William L. Gerald
- Department of Pathology, Human Oncology and Pathogenesis Program, Memorial Sloan-Kettering Cancer Center, New York, New York 10021, USA
| | | | - Alexandra C. Newton
- Department of Pharmacology, University of California San Diego, La Jolla, California 92093, USA
| | - Brett S. Carver
- Department of Surgery, Division of Urology, Human Oncology and Pathogenesis Program, Memorial Sloan-Kettering Cancer Center, New York, New York 10021, USA
| | - Lloyd C. Trotman
- Cold Spring Harbor Laboratory, One Bungtown Road, Cold Spring Harbor, New York 11724, USA
- Correspondence: Lloyd C. Trotman (), Phone: (516)-367-5054, Fax: (516)-367-8454
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Qiao M, Shi Q, Pardee AB. The pursuit of oncotargets through understanding defective cell regulation. Oncotarget 2010; 1:544-51. [PMID: 21317450 PMCID: PMC3248140 DOI: 10.18632/oncotarget.101010] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2010] [Accepted: 10/18/2010] [Indexed: 12/21/2022] Open
Abstract
More effective anticancer agents are essential, as has too often been demonstrated by the paucity of therapeutics which preserve life. Their discovery is very difficult. Many approaches are being applied, from testing folk medicines to automated high throughput screening of large chemical libraries. Mutations in cancer cells create dysfunctional regulatory systems. This Perspective summarizes an approach to applying defective molecular control mechanisms as oncotargets on which drug discoveries against cancer can be based.
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Affiliation(s)
- Meng Qiao
- University of California, Irvine Biological Chemistry, 140 Sprague Hall, 839 Health Sciences Rd, Irvine, CA 92697-1700
| | - Qian Shi
- Institutes of Biomedical Sciences, Fudan University,130 Dong An Road, Box 281, Shanghai, China 20003
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Qiao M, Shi Q, Pardee AB. The pursuit of oncotargets through understanding defective cell regulation. Oncotarget 2010; 1:544-551. [PMID: 21317450 PMCID: PMC3248140 DOI: 10.18632/oncotarget.189] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2010] [Accepted: 10/18/2010] [Indexed: 11/25/2022] Open
Abstract
More effective anticancer agents are essential, as has too often been demonstrated by the paucity of therapeutics which preserve life. Their discovery is very difficult. Many approaches are being applied, from testing folk medicines to automated high throughput screening of large chemical libraries. Mutations in cancer cells create dysfunctional regulatory systems. This Perspective summarizes an approach to applying defective molecular control mechanisms as oncotargets on which drug discoveries against cancer can be based.
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Affiliation(s)
- Meng Qiao
- University of California, Irvine Biological Chemistry, 140 Sprague Hall, 839 Health Sciences Rd, Irvine, CA 92697-1700
| | - Qian Shi
- Institutes of Biomedical Sciences, Fudan University,130 Dong An Road, Box 281, Shanghai, China 20003
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Jackson TC, Verrier JD, Semple-Rowland S, Kumar A, Foster TC. PHLPP1 splice variants differentially regulate AKT and PKCα signaling in hippocampal neurons: characterization of PHLPP proteins in the adult hippocampus. J Neurochem 2010; 115:941-55. [PMID: 20819118 DOI: 10.1111/j.1471-4159.2010.06984.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Pleckstrin homology and leucine rich repeat protein phosphatases (PHLPPs) are a novel class of potent protein kinase B (AKT) inhibitors that have been intensely investigated in relation to AKT activity in cancer. Currently, our understanding of the role of PHLPP1α in the central nervous system is limited. In this study, we characterized PHLPP protein expression and target kinases in the adult hippocampus. We directly verify PHLPP1α inhibits AKT in hippocampal neurons and demonstrate a novel role for PHLPP1β/SCOP, to promote AKT activation. PHLPP1α expression changes dramatically in the hippocampus during development, constituting the most abundant PHLPP protein in adult neurons. Further, while all PHLPP proteins could be observed in the cytosolic fraction, only PHLPP1α could be localized to the nucleus. The results provide unique evidence for a divergence in the function of PHLPP1α and PHLPP1β/SCOP, and suggest that PHLPP1α plays a major role in regulating AKT signaling in neurons.
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Affiliation(s)
- Travis C Jackson
- Department of Neuroscience, McKnight Brain Institute, University of Florida, Gainesville, Florida 32610-0244, USA
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