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Zhao S, Liu H, Wang H, He X, Tang J, Qi S, Yang R, Xie J. Inhibition of phosphatidylinositol 3-kinase catalytic subunit alpha by miR-203a-3p reduces hypertrophic scar formation via phosphatidylinositol 3-kinase/AKT/mTOR signaling pathway. BURNS & TRAUMA 2024; 12:tkad048. [PMID: 38179473 PMCID: PMC10762504 DOI: 10.1093/burnst/tkad048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Revised: 07/24/2023] [Accepted: 09/12/2023] [Indexed: 01/06/2024]
Abstract
Background Hypertrophic scar (HS) is a common fibroproliferative skin disease that currently has no truly effective therapy. Given the importance of phosphatidylinositol 3-kinase catalytic subunit alpha (PIK3CA) in hypertrophic scar formation, the development of therapeutic strategies for endogenous inhibitors against PIK3CA is of great interest. Here, we explored the molecular mechanisms underlying the protective effects of miR-203a-3p (PIK3CA inhibitor) against excessive scar. Methods Bioinformatic analysis, immunohistochemistry, immunofluorescence, miRNA screening and fluorescence in situ hybridization assays were used to identify the possible pathways and target molecules mediating HS formation. A series of in vitro and in vivo experiments were used to clarify the role of PIK3CA and miR-203a-3p in HS. Mechanistically, transcriptomic sequencing, immunoblotting, dual-luciferase assay and rescue experiments were executed. Results Herein, we found that PIK3CA and the phosphatidylinositol 3-kinase (PI3K)/AKT/mTOR pathway were upregulated in scar tissues and positively correlated with fibrosis. We then identified miR-203a-3p as the most suitable endogenous inhibitor of PIK3CA. miR-203a-3p suppressed the proliferation, migration, collagen synthesis and contractility as well as the transdifferentiation of fibroblasts into myofibroblasts in vitro, and improved the morphology and histology of scars in vivo. Mechanistically, miR-203a-3p attenuated fibrosis by inactivating the PI3K/AKT/mTOR pathway by directly targeting PIK3CA. Conclusions PIK3CA and the PI3K/AKT/mTOR pathway are actively involved in scar fibrosis and miR-203a-3p might serve as a potential strategy for hypertrophic scar therapy through targeting PIK3CA and inactivating the PI3K/AKT/mTOR pathway.
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Affiliation(s)
- Shixin Zhao
- Department of Burns, The First Affiliated Hospital of Sun Yat-Sen University, No. 58 Zhongshan Second Road, Yuexiu District, Guangzhou, Guangdong, 510062, China
- Guangdong Provincial Engineering Technology Research Center of Burn and Wound Accurate Diagnosis and Treatment Key Technology and Series of Products, Sun Yat-Sen University, No. 58 Zhongshan Second Road, Yuexiu District, Guangzhou, Guangdong, 510062, China
| | - Hengdeng Liu
- Department of Burns, The First Affiliated Hospital of Sun Yat-Sen University, No. 58 Zhongshan Second Road, Yuexiu District, Guangzhou, Guangdong, 510062, China
- Guangdong Provincial Engineering Technology Research Center of Burn and Wound Accurate Diagnosis and Treatment Key Technology and Series of Products, Sun Yat-Sen University, No. 58 Zhongshan Second Road, Yuexiu District, Guangzhou, Guangdong, 510062, China
| | - Hanwen Wang
- Department of Burns, The First Affiliated Hospital of Sun Yat-Sen University, No. 58 Zhongshan Second Road, Yuexiu District, Guangzhou, Guangdong, 510062, China
- Guangdong Provincial Engineering Technology Research Center of Burn and Wound Accurate Diagnosis and Treatment Key Technology and Series of Products, Sun Yat-Sen University, No. 58 Zhongshan Second Road, Yuexiu District, Guangzhou, Guangdong, 510062, China
| | - Xuefeng He
- Department of Burns, The First Affiliated Hospital of Sun Yat-Sen University, No. 58 Zhongshan Second Road, Yuexiu District, Guangzhou, Guangdong, 510062, China
- Guangdong Provincial Engineering Technology Research Center of Burn and Wound Accurate Diagnosis and Treatment Key Technology and Series of Products, Sun Yat-Sen University, No. 58 Zhongshan Second Road, Yuexiu District, Guangzhou, Guangdong, 510062, China
| | - Jinming Tang
- Department of Burns, The First Affiliated Hospital of Sun Yat-Sen University, No. 58 Zhongshan Second Road, Yuexiu District, Guangzhou, Guangdong, 510062, China
- Guangdong Provincial Engineering Technology Research Center of Burn and Wound Accurate Diagnosis and Treatment Key Technology and Series of Products, Sun Yat-Sen University, No. 58 Zhongshan Second Road, Yuexiu District, Guangzhou, Guangdong, 510062, China
| | - Shaohai Qi
- Department of Burns, The First Affiliated Hospital of Sun Yat-Sen University, No. 58 Zhongshan Second Road, Yuexiu District, Guangzhou, Guangdong, 510062, China
- Guangdong Provincial Engineering Technology Research Center of Burn and Wound Accurate Diagnosis and Treatment Key Technology and Series of Products, Sun Yat-Sen University, No. 58 Zhongshan Second Road, Yuexiu District, Guangzhou, Guangdong, 510062, China
| | - Ronghua Yang
- Department of Burn and Plastic Surgery, Guangzhou First People's Hospital, South China University of technology, No. 1 Panfu Road, Yuexiu District, Guangzhou, Guangdong, 510062, China
| | - Julin Xie
- Department of Burns, The First Affiliated Hospital of Sun Yat-Sen University, No. 58 Zhongshan Second Road, Yuexiu District, Guangzhou, Guangdong, 510062, China
- Guangdong Provincial Engineering Technology Research Center of Burn and Wound Accurate Diagnosis and Treatment Key Technology and Series of Products, Sun Yat-Sen University, No. 58 Zhongshan Second Road, Yuexiu District, Guangzhou, Guangdong, 510062, China
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Hou X, Chen D, Wang Y, Cui B, Xu H, Wang Y, Chen H, Wang D, Chen Y, Cheng T, Dai X. Network analysis to explore the pharmacological mechanism of Shenmai injection in treating granulocytopenia and evidence-based medicine approach validation. Medicine (Baltimore) 2023; 102:e33825. [PMID: 37335746 DOI: 10.1097/md.0000000000033825] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 06/21/2023] Open
Abstract
BACKGROUND Shenmai injection is frequently utilized in China to clinically treat granulocytopenia in oncology patients following chemotherapy. Despite this, the drug's therapeutic benefits remain a topic of contention, and its active components and potential treatment targets have yet to be established. The present study utilizes a network pharmacology approach to investigate the drug's active ingredients and possible therapeutic targets, and to evaluate the effectiveness of Shenmai injection in treating granulocytopenia through meta-analysis. METHODS In our subject paper, we utilized the TCMID database to investigate the active ingredients present in red ginseng and ophiopogon japonicus. To further identify molecular targets, we employed SuperPred, as well as OMIM, Genecards, and DisGeNET databases. Our focus was on targets associated with granulocytopenia. The DAVID 6.8 database was utilized to perform gene ontology functional enrichment analysis and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis. Additionally, a protein-protein interaction network was established. The resulting "drug-key component-potential target-core pathway" network was used to predict the mechanism of action of Shenmai injection in the treatment of granulocytopenia. In order to evaluate the quality of the studies included in our analysis, we utilized the Cochrane Reviewers' Handbook. We then conducted a meta-analysis of the clinical curative effect of Shenmai injection for granulocytopenia, utilizing the Cochrane Collaboration's RevMan 5.3 software. RESULTS After conducting a thorough screening, the study identified 5 primary ingredients of Shenmai injection - ophiopogonoside a, β-patchoulene, ginsenoside rf, ginsenoside re, and ginsenoside rg1-that can potentially target 5 essential proteins: STAT3, TLR4, PIK3CA, PIK3R1, and GRB2. Additionally, Kyoto Encyclopedia of Genes and Genomes pathway analysis revealed that Shenmai injection can be beneficial in treating granulocytopenia by interacting with pathways such as HIF-1 signaling, T-cell receptor signaling, PI3K-Akt signaling, chemokine signaling, and FoxO signaling. The results of meta-analysis indicate that the treatment group exhibited superior performance in terms of both efficiency and post-treatment leukocyte count when compared to the control group. CONCLUSION In summary, studies in network pharmacology demonstrate that Shenmai injection exerts an impact on granulocytopenia via various components, targets, and mechanisms. Additionally, evidence-based studies provide strong support for the effectiveness of Shenmai injection in preventing and treating granulocytopenia.
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Affiliation(s)
- Xianbing Hou
- Department of Oncology, Fenghua Hospital of Traditional Chinese Medicine, Ningbo, China
| | - Dandan Chen
- Department of Rehabilitation, Fenghua Hospital of Traditional Chinese Medicine, Ningbo, China
| | - Yao Wang
- Department of Oncology, Fenghua Hospital of Traditional Chinese Medicine, Ningbo, China
| | - Bixian Cui
- Department of Oncology, Fenghua Hospital of Traditional Chinese Medicine, Ningbo, China
| | - Hui Xu
- Department of Oncology, Fenghua Hospital of Traditional Chinese Medicine, Ningbo, China
| | - Yuanyuan Wang
- Department of Oncology, Fenghua Hospital of Traditional Chinese Medicine, Ningbo, China
| | - Hongzhou Chen
- Department of Oncology, Fenghua Hospital of Traditional Chinese Medicine, Ningbo, China
| | - Dan Wang
- Department of Nursing, Fenghua Hospital of Traditional Chinese Medicine, Ningbo, China
| | - Ying Chen
- Department of Nursing, Fenghua Hospital of Traditional Chinese Medicine, Ningbo, China
| | - Tongfei Cheng
- Department of Nursing, Fenghua Hospital of Traditional Chinese Medicine, Ningbo, China
| | - Xiaojun Dai
- Department of Nursing, Fenghua Hospital of Traditional Chinese Medicine, Ningbo, China
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Hall DCN, Benndorf RA. Aspirin sensitivity of PIK3CA-mutated Colorectal Cancer: potential mechanisms revisited. Cell Mol Life Sci 2022; 79:393. [PMID: 35780223 PMCID: PMC9250486 DOI: 10.1007/s00018-022-04430-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Revised: 06/01/2022] [Accepted: 06/14/2022] [Indexed: 11/30/2022]
Abstract
PIK3CA mutations are amongst the most prevalent somatic mutations in cancer and are associated with resistance to first-line treatment along with low survival rates in a variety of malignancies. There is evidence that patients carrying PIK3CA mutations may benefit from treatment with acetylsalicylic acid, commonly known as aspirin, particularly in the setting of colorectal cancer. In this regard, it has been clarified that Class IA Phosphatidylinositol 3-kinases (PI3K), whose catalytic subunit p110α is encoded by the PIK3CA gene, are involved in signal transduction that regulates cell cycle, cell growth, and metabolism and, if disturbed, induces carcinogenic effects. Although PI3K is associated with pro-inflammatory cyclooxygenase-2 (COX-2) expression and signaling, and COX-2 is among the best-studied targets of aspirin, the mechanisms behind this clinically relevant phenomenon are still unclear. Indeed, there is further evidence that the protective, anti-carcinogenic effect of aspirin in this setting may be mediated in a COX-independent manner. However, until now the understanding of aspirin's prostaglandin-independent mode of action is poor. This review will provide an overview of the current literature on this topic and aims to analyze possible mechanisms and targets behind the aspirin sensitivity of PIK3CA-mutated cancers.
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Affiliation(s)
- Daniella C N Hall
- Department of Clinical Pharmacy and Pharmacotherapy, Institute of Pharmacy, Martin-Luther-University Halle-Wittenberg, Kurt-Mothes-Str. 3, 06120, Halle (Saale), Germany
| | - Ralf A Benndorf
- Department of Clinical Pharmacy and Pharmacotherapy, Institute of Pharmacy, Martin-Luther-University Halle-Wittenberg, Kurt-Mothes-Str. 3, 06120, Halle (Saale), Germany.
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Function, Regulation and Biological Roles of PI3Kγ Variants. Biomolecules 2019; 9:biom9090427. [PMID: 31480354 PMCID: PMC6770443 DOI: 10.3390/biom9090427] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Revised: 08/14/2019] [Accepted: 08/15/2019] [Indexed: 12/19/2022] Open
Abstract
Phosphatidylinositide 3-kinase (PI3K) γ is the only class IB PI3K member playing significant roles in the G-protein-dependent regulation of cell signaling in health and disease. Originally found in the immune system, increasing evidence suggest a wide array of functions in the whole organism. PI3Kγ occur as two different heterodimeric variants: PI3Kγ (p87) and PI3Kγ (p101), which share the same p110γ catalytic subunit but differ in their associated non-catalytic subunit. Here we concentrate on specific PI3Kγ features including its regulation and biological functions. In particular, the roles of its non-catalytic subunits serving as the main regulators determining specificity of class IB PI3Kγ enzymes are highlighted.
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Irvine WA, Flanagan JU, Allison JR. Computational Prediction of Amino Acids Governing Protein-Membrane Interaction for the PIP3 Cell Signaling System. Structure 2019; 27:371-380.e3. [DOI: 10.1016/j.str.2018.10.014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Revised: 08/13/2018] [Accepted: 10/18/2018] [Indexed: 10/27/2022]
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Maheshwari S, Miller MS, O'Meally R, Cole RN, Amzel LM, Gabelli SB. Kinetic and structural analyses reveal residues in phosphoinositide 3-kinase α that are critical for catalysis and substrate recognition. J Biol Chem 2017; 292:13541-13550. [PMID: 28676499 DOI: 10.1074/jbc.m116.772426] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Revised: 06/30/2017] [Indexed: 12/26/2022] Open
Abstract
Phosphoinositide 3-kinases (PI3Ks) are ubiquitous lipid kinases that activate signaling cascades controlling cell survival, proliferation, protein synthesis, and vesicle trafficking. PI3Ks have dual kinase specificity: a lipid kinase activity that phosphorylates the 3'-hydroxyl of phosphoinositides and a protein-kinase activity that includes autophosphorylation. Despite the wealth of biochemical and structural information on PI3Kα, little is known about the identity and roles of individual active-site residues in catalysis. To close this gap, we explored the roles of residues of the catalytic domain and the regulatory subunit of human PI3Kα in lipid and protein phosphorylation. Using site-directed mutagenesis, kinetic assays, and quantitative mass spectrometry, we precisely mapped key residues involved in substrate recognition and catalysis by PI3Kα. Our results revealed that Lys-776, located in the P-loop of PI3Kα, is essential for the recognition of lipid and ATP substrates and also plays an important role in PI3Kα autophosphorylation. Replacement of the residues His-936 and His-917 in the activation and catalytic loops, respectively, with alanine dramatically changed PI3Kα kinetics. Although H936A inactivated the lipid kinase activity without affecting autophosphorylation, H917A abolished both the lipid and protein kinase activities of PI3Kα. On the basis of these kinetic and structural analyses, we propose possible mechanistic roles of these critical residues in PI3Kα catalysis.
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Affiliation(s)
- Sweta Maheshwari
- From the Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205
| | - Michelle S Miller
- Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21287
| | - Robert O'Meally
- Mass Spectrometry and Proteomics Facility, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, and
| | - Robert N Cole
- Mass Spectrometry and Proteomics Facility, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, and
| | - L Mario Amzel
- From the Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205,
| | - Sandra B Gabelli
- From the Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, .,Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21287.,Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205
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7
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Watson LJ, Alexander KM, Mohan ML, Bowman AL, Mangmool S, Xiao K, Naga Prasad SV, Rockman HA. Phosphorylation of Src by phosphoinositide 3-kinase regulates beta-adrenergic receptor-mediated EGFR transactivation. Cell Signal 2016; 28:1580-92. [PMID: 27169346 DOI: 10.1016/j.cellsig.2016.05.006] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Revised: 05/03/2016] [Accepted: 05/05/2016] [Indexed: 01/08/2023]
Abstract
β2-Adrenergic receptors (β2AR) transactivate epidermal growth factor receptors (EGFR) through formation of a β2AR-EGFR complex that requires activation of Src to mediate signaling. Here, we show that both lipid and protein kinase activities of the bifunctional phosphoinositide 3-kinase (PI3K) enzyme are required for β2AR-stimulated EGFR transactivation. Mechanistically, the generation of phosphatidylinositol (3,4,5)-tris-phosphate (PIP3) by the lipid kinase function stabilizes β2AR-EGFR complexes while the protein kinase activity of PI3K regulates Src activation by direct phosphorylation. The protein kinase activity of PI3K phosphorylates serine residue 70 on Src to enhance its activity and induce EGFR transactivation following βAR stimulation. This newly identified function for PI3K, whereby Src is a substrate for the protein kinase activity of PI3K, is of importance since Src plays a key role in pathological and physiological signaling.
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Affiliation(s)
- Lewis J Watson
- Department of Medicine, Duke University Medical Center, Durham, NC 27710, United States
| | - Kevin M Alexander
- Department of Medicine, Duke University Medical Center, Durham, NC 27710, United States
| | - Maradumane L Mohan
- Department of Molecular Cardiology, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, OH 44195, United States
| | - Amber L Bowman
- Department of Medicine, Duke University Medical Center, Durham, NC 27710, United States
| | - Supachoke Mangmool
- Department of Pharmacology, Faculty of Pharmacy, Mahidol University, Thailand
| | - Kunhong Xiao
- Department of Medicine, Duke University Medical Center, Durham, NC 27710, United States; Department of Pharmacology and Chemical Biology, University of Pittsburg School of Medicine, Pittsburgh, PA 15261, United States
| | - Sathyamangla V Naga Prasad
- Department of Molecular Cardiology, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, OH 44195, United States.
| | - Howard A Rockman
- Department of Medicine, Duke University Medical Center, Durham, NC 27710, United States; Department of Cell Biology, Duke University Medical Center, Durham, NC 27710, United States; Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710, United States.
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Balasubramaniam SL, Gopalakrishnapillai A, Gangadharan V, Duncan RL, Barwe SP. Sodium-calcium exchanger 1 regulates epithelial cell migration via calcium-dependent extracellular signal-regulated kinase signaling. J Biol Chem 2015; 290:12463-73. [PMID: 25770213 DOI: 10.1074/jbc.m114.629519] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2014] [Indexed: 12/16/2022] Open
Abstract
Na(+)/Ca(2+) exchanger-1 (NCX1) is a major calcium extrusion mechanism in renal epithelial cells enabling the efflux of one Ca(2+) ion and the influx of three Na(+) ions. The gradient for this exchange activity is provided by Na,K-ATPase, a hetero-oligomer consisting of a catalytic α-subunit and a regulatory β-subunit (Na,K-β) that also functions as a motility and tumor suppressor. We showed earlier that mice with heart-specific ablation (KO) of Na,K-β had a specific reduction in NCX1 protein and were ouabain-insensitive. Here, we demonstrate that Na,K-β associates with NCX1 and regulates its localization to the cell surface. Madin-Darby canine kidney cells with Na,K-β knockdown have reduced NCX1 protein and function accompanied by 2.1-fold increase in free intracellular calcium and a corresponding increase in the rate of cell migration. Increased intracellular calcium up-regulated ERK1/2 via calmodulin-dependent activation of PI3K. Both myosin light chain kinase and Rho-associated kinase acted as mediators of ERK1/2-dependent migration. Restoring NCX1 expression in β-KD cells reduced migration rate and ERK1/2 activation, suggesting that NCX1 functions downstream of Na,K-β in regulating cell migration. In parallel, inhibition of NCX1 by KB-R7943 in Madin-Darby canine kidney cells, LLC-PK1, and human primary renal epithelial cells (HREpiC) increased ERK1/2 activation and cell migration. This increased migration was associated with high myosin light chain phosphorylation by PI3K/ERK-dependent mechanism in HREpiC cells. These data confirm the role of NCX1 activity in regulating renal epithelial cell migration.
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Affiliation(s)
- Sona Lakshme Balasubramaniam
- From the Nemours Center for Childhood Cancer Research, Alfred I. duPont Hospital for Children, Wilmington, Delaware 19803 and Department of Biological Sciences, University of Delaware, Newark, Delaware 19716
| | - Anilkumar Gopalakrishnapillai
- From the Nemours Center for Childhood Cancer Research, Alfred I. duPont Hospital for Children, Wilmington, Delaware 19803 and
| | - Vimal Gangadharan
- Department of Biological Sciences, University of Delaware, Newark, Delaware 19716
| | - Randall L Duncan
- Department of Biological Sciences, University of Delaware, Newark, Delaware 19716
| | - Sonali P Barwe
- From the Nemours Center for Childhood Cancer Research, Alfred I. duPont Hospital for Children, Wilmington, Delaware 19803 and Department of Biological Sciences, University of Delaware, Newark, Delaware 19716
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Abstract
Phosphoinositide 3-OH kinase (PI3K) regulates a number of developmental and physiologic processes in skeletal muscle; however, the contributions of individual PI3K p110 catalytic subunits to these processes are not well-defined. To address this question, we investigated the role of the 110-kDa PI3K catalytic subunit β (p110β) in myogenesis and metabolism. In C2C12 cells, pharmacological inhibition of p110β delayed differentiation. We next generated mice with conditional deletion of p110β in skeletal muscle (p110β muscle knockout [p110β-mKO] mice). While young p110β-mKO mice possessed a lower quadriceps mass and exhibited less strength than control littermates, no differences in muscle mass or strength were observed between genotypes in old mice. However, old p110β-mKO mice were less glucose tolerant than old control mice. Overexpression of p110β accelerated differentiation in C2C12 cells and primary human myoblasts through an Akt-dependent mechanism, while expression of kinase-inactive p110β had the opposite effect. p110β overexpression was unable to promote myoblast differentiation under conditions of p110α inhibition, but expression of p110α was able to promote differentiation under conditions of p110β inhibition. These findings reveal a role for p110β during myogenesis and demonstrate that long-term reduction of skeletal muscle p110β impairs whole-body glucose tolerance without affecting skeletal muscle size or strength in old mice.
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Zhou GZ, Xu SL, Sun GC, Chen XB. Novel curcumin analogue IHCH exhibits potent anti‑proliferative effects by inducing autophagy in A549 lung cancer cells. Mol Med Rep 2014; 10:441-6. [PMID: 24788478 DOI: 10.3892/mmr.2014.2183] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2013] [Accepted: 03/24/2014] [Indexed: 11/06/2022] Open
Abstract
Curcumin is a natural polyphenolic compound that exhibits strong antioxidant and anticancer activities; however, low bioavailability has restricted its application in chemotherapeutic trials. The present study aimed to investigate the anticancer effect of the novel curcumin derivative 2E,6E‑2‑(1H‑indol‑3‑yl) methylene)‑6‑(4‑hydroxy‑3‑methoxy benzylidene)‑cyclohexanone (IHCH) on A549 lung cancer cells. Cells were treated with IHCH at different concentrations (1‑40 µM) for different time periods (1‑36 h). Microscopic analysis revealed that IHCH inhibited A549 cell growth and induced the formation of characteristic autophagolysosomes in a dose‑ and time‑dependent manner. Furthermore, the inhibitory rate of IHCH (40 µM) on A549 cell viability was 77.34% after 36 h of treatment. Acridine orange staining revealed an increase in autophagic vacuoles in the IHCH‑treated A549 cells. Monodansylcadaverine staining was used to analyze autophagy rate. Immunocytochemistry revealed an increase in light chain (LC) 3 protein expression in the IHCH‑treated cells and western blot analysis detected the conversion of LC3‑I to LC3‑II, as well as the recruitment of LC3 to autophagosomes in the cytoplasmatic compartment, suggesting the occurrence of autophagy. These findings show that IHCH induced autophagy in A549 cells, which is a novel cell death mechanism induced by curcumin derivatives.
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Affiliation(s)
- Guang-Zhou Zhou
- College of Bioengineering, Henan University of Technology, Zhengzhou, Henan 450001, P.R. China
| | - Su-Li Xu
- College of Bioengineering, Henan University of Technology, Zhengzhou, Henan 450001, P.R. China
| | - Gang-Chun Sun
- College of Chemistry and Chemical Engineering, Henan University of Technology, Zhengzhou, Henan 450001, P.R. China
| | - Xiao-Bing Chen
- The Affiliated Cancer Hospital of Zhengzhou University, Zhengzhou, Henan 450008, P.R. China
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Structure, function and inhibition of the phosphoinositide 3-kinase p110α enzyme. Biochem Soc Trans 2014; 42:120-4. [DOI: 10.1042/bst20130255] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The PI3K (phosphoinositide 3-kinase) p110α isoform is activated by oncogenic mutations in many cancers. This has stimulated intense interest in identifying inhibitors of the PI3K pathway as well as p110α-selective inhibitors, and understanding the mechanisms underlying activation by the oncogenic mutations. In the present article, we review recent progress in the structure and function of the p110α enzyme and two of its most common oncogenic mutations, the development of isoform-selective inhibitors, and p110α pharmacology.
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Enzyme activity effects of N-terminal His-tag attached to catalytic sub-unit of phosphoinositide-3-kinase. Biosci Rep 2013; 33:BSR20130075. [PMID: 23968392 PMCID: PMC3817851 DOI: 10.1042/bsr20130075] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
NTT (N-terminal tags) on the catalytic (p110) sub-unit of PI 3-K (phosphoinositol 3-kinase) have previously been shown to increase cell signalling and oncogenic transformation. Here we test the impact of an NT (N-terminal) His-tag on in vitro lipid and protein kinase activity of all class-1 PI 3-K isoforms and two representative oncogenic mutant forms (E545K and H1047R), in order to elucidate the mechanisms behind this elevated signalling and transformation observed in vivo. Our results show that an NT His-tag has no impact on lipid kinase activity as measured by enzyme titration, kinetics and inhibitor susceptibility. Conversely, the NT His-tag did result in a differential effect on protein kinase activity, further potentiating the elevated protein kinase activity of both the helical domain and catalytic domain oncogenic mutants with relation to p110 phosphorylation. All other isoforms also showed elevated p110 phosphorylation (although not statistically significant). We conclude that the previously reported increase in cell signalling and oncogenic-like transformation in response to p110 NTT is not mediated via an increase in the lipid kinase activity of PI 3-K, but may be mediated by increased p110 autophosphorylation and/or other, as yet unidentified, intracellular protein/protein interactions. We further observe that tagged recombinant protein is suitable for use in in vitro lipid kinase screens to identify PI 3-K inhibitors; however, we recommend that in vivo (including intracellular) experiments and investigations into the protein kinase activity of PI 3-K should be conducted with untagged constructs.
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