DOCSLIB.ORG

Genomically Amplified Akt3 Activates DNA Repair Pathway and Promotes Glioma Progression

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Genomically Amplified Akt3 Activates DNA Repair Pathway and Promotes Glioma Progression Genomically amplified Akt3 activates DNA repair pathway and promotes glioma progression Kristen M. Turnera,1, Youting Suna,2, Ping Jia, Kirsi J. Granberga,b, Brady Bernardc, Limei Hua, David E. Cogdella, Xinhui Zhoua, Olli Yli-Harjab, Matti Nykterb, Ilya Shmulevichc, W. K. Alfred Yungd, Gregory N. Fullera, and Wei Zhanga,3 Departments of aPathology and dNeuro-Oncology, University of Texas MD Anderson Cancer Center, Houston, TX 77030; bDepartment of Signal Processing, Tampere University of Technology, Tampere, 33720, Finland; and cDepartment of Systems Biology, Institute for Systems Biology, Seattle, WA 98109 Edited* by Webster K. Cavenee, Ludwig Institute for Cancer Research, University of California, San Diego, La Jolla, CA, and approved February 13, 2015 (received for review July 30, 2014) Akt is a robust oncogene that plays key roles in the development disease progression and maintenance, whereas Akt1 does not play and progression of many cancers, including glioma. We evaluated a major role (15, 16). Another study in transformed mouse astro- the differential propensities of the Akt isoforms toward progression cytes indicate that Akt isoform function is potentially modulated by in the well-characterized RCAS/Ntv-a mouse model of PDGFB-driven the genetic landscape of the tumor (17). The underlying basis be- low grade glioma. A constitutively active myristoylated form of hind these differences and the major pathways that the isoforms Akt1 did not induce high-grade glioma (HGG). In stark contrast, Akt2 use remains largely unknown. To our knowledge, our study is the and Akt3 showed strong progression potential with 78% and 97% first to use a glial-specific transgenic mouse model to demonstrate of tumors diagnosed as HGG, respectively. We further revealed that Akt3 as a powerful inducer of glioma progression and to further significant variations in polarity and hydropathy values among the reveal the previously unidentified DNA repair function of Akt3. Akt isoforms in both the pleckstrin homology domain (P domain) and regulatory domain (R domain) were critical in mediating glioma Results and Discussion progression. Gene expression profiles from representative Akt- Akt3 Tops Hierarchy in Mediating Glioma Progression. To gain a broad derived tumors indicated dominant and distinct roles for Akt3, perspective of the Akt isoforms in human cancer, we analyzed consisting primarily of DNA repair pathways. TCGA data from their copy number variation (CNV) across multiple cancer types. human GBM closely reflected the DNA repair function, as Akt3 Akt3 comprised the most frequently amplified isoform in many was significantly correlated with a 76-gene signature DNA repair cancers, including GBM, ovarian, melanoma, endometrial, and panel. Consistently, compared with Akt1 and Akt2 overexpres- breast cancer (Fig. 1A). Moreover, Akt3 was the least frequently sion models, Akt3-expressing human GBM cells had enhanced deleted isoform. In contrast, Akt1 was the least frequently ampli- activation of DNA repair proteins, leading to increased DNA fied and most deleted isoform. These CNV data suggest that Akt3 repair and subsequent resistance to radiation and temozolo- may be the most critical isoform in an array of cancer types. Indeed, mide. Given the wide range of Akt3-amplified cancers, Akt3 a prominent role for Akt3 has been well-documented in melanoma, may represent a key resistance factor. playing a critical role in tumor progression (18) and rendering cells resistant to apoptosis (19). Akt3 has also been reported to be Akt | glioma | DNA repair | RCAS/tv-a mouse model the dominant isoform in hormone unresponsive breast (20) and kt is among the most hyperactivated signaling pathways in Significance Ahuman cancer and is an important kinase that regulates key cellular functions including cell growth, proliferation, angiogen- Glioblastoma is the most common and aggressive type of gli- esis, glucose metabolism, invasion, and survival, among others oma, with a median survival of 15 mo. A major obstacle to ef- (1–3). Analysis of human glioblastomas (GBMs) from The Cancer fective treatment is de novo or acquired resistance to standard- Genome Atlas (TCGA) has revealed that the Akt signaling path- care therapies, including radiation and temozolomide. Enhanced way is one of the top altered pathways in GBM (4, 5). Additionally, DNA repair can allow damaged or mutated cells to survive, con- researchers have observed that the Akt activation status correlates tributing to resistance and tumor recurrence. We have identified with glioma grade (6). However, much less is known regarding the Akt3 as the dominant Akt isoform that robustly stimulates glioma precise roles of the Akt isoforms (Akt1, Akt2, Akt3) in this disease. progression. We also discovered key roles for Akt3 in activating Akt1, Akt2, and Akt3 share roughly 80% overall sequence DNA repair pathways, which led to enhanced survival of human identity and each contain three similar domains: a pleckstrin ho- glioblastoma cells following radiation or temozolomide treat- mology, kinase, and regulatory domain (7). Although they appear ment. Our work has potential broad application to multiple cancer to be very similar proteins, developmental studies as well as as- types in which Akt3 is expressed. Blocking this pathway may help sessment of the isoforms in cancer models have revealed that they prevent or alleviate DNA repair-mediated therapeutic resistance. possess distinct functions (1, 8). The most extensive work on iso- form differences has been performed in breast cancer. Akt2 is Author contributions: K.M.T., O.Y.-H., M.N., I.S., G.N.F., and W.Z. designed research; K.M.T., P.J., K.J.G., L.H., D.E.C., and X.Z. performed research; K.M.T., Y.S., K.J.G., B.B., O.Y.-H., M.N., reported to promote migration, invasion, and metastasis, whereas I.S., W.K.A.Y., G.N.F., and W.Z. analyzed data; and K.M.T., W.K.A.Y., G.N.F., and W.Z. wrote Akt1 is inhibitory (8, 9). Specific phosphorylation of palladin, an the paper. actin bundling protein, by Akt1 led to decreased migration (10). The authors declare no conflict of interest. CELL BIOLOGY Conversely, Akt2 has been found to promote breast cancer epi- *This Direct Submission article had a prearranged editor. thelial to mesenchymal transition (EMT) through miR-200 mod- Data deposition: The sequences reported in this paper have been deposited in the Gene ulation (11) as well as an interaction with Snail1 on the E-cadherin Expression Omnibus (GEO) database, www.ncbi.nlm.nih.gov/geo (accession no. GSE66177). promoter (12). Functional differences in glioma have been slightly 1Present address: Ludwig Institute for Cancer Research, University of California, San variable by using knockdown systems in transformed cells. The Diego, La Jolla, CA 92093. first studies were reported on Akt2 only, which was found to 2Present address: Sequenom Laboratories, San Diego, CA 92121. mediate invasion in rat C6 glioma cells (13), and inhibition of Akt2 3To whom correspondence should be addressed. Email: [email protected]. prolonged survival in an orthotopic rat model (14). Subsequent This article contains supporting information online at www.pnas.org/lookup/suppl/doi:10. reports have found that Akt2, and possibly Akt3, are important for 1073/pnas.1414573112/-/DCSupplemental. www.pnas.org/cgi/doi/10.1073/pnas.1414573112 PNAS | March 17, 2015 | vol. 112 | no. 11 | 3421–3426 Downloaded by guest on October 1, 2021 Fig. 1. Akt3 frequently amplified in cancer and tops hierarchy in glioma. (A) Copy number variation of Akt isoforms in TCGA cancers, shown in order of increasing Akt3 amplification percentage. (B) Percentage of HGG and representative tumors shown from Akt isoforms injected in conjunction with PDGFB. P values represent Fisher’s exact test. *P < 0.05, ***P < 0.001. Scale bar for images and insets, 100 and 50 μm, respectively. prostate cancer cells (21), and a recurrent MAGI3-Akt3 fusion gene independent growth in transformed astrocytes (17). Additionally, was recently discovered in triple-negative breast cancer (22). Given the cellular localization pattern of the activated form of Akt (pAkt- that Akt3 represents 50% of total Akt in the normal brain, has 473) isoforms appeared to be distinct, perhaps providing clues of been documented to be essential for normal brain development differential pathways being activated. Tumors derived from Akt1 (23), and was preferentially amplified in GBM, we hypothesized displayed mostly nuclear staining of pAkt; Akt2 tumors displayed that Akt3 is the most critical isoform involved in glioma. primarily membranous staining; whereas Akt3 tumors displayed We directly tested the ability of Akt1, Akt2, and Akt3 to promote strong nuclear and cytoplasmic staining (Fig. 1B). These findings glioma progression in the RCAS/Ntv-a glial-specific mouse system. are consistent with a recent phosphoproteomics screen in immor- As previously reported, injection of the RCAS plasmid carrying talized lung fibroblasts, which revealed more evenly distributed PDGFB transduces normal, nestin-positive glial cells that are nuclear and cytoplasmic substrates in cells expressing Akt3, com- engineered to express the RCAS receptor, tv-a, leading to forma- pared with those in Akt1- and Akt2-expressing cells (27). This tion of low-grade glioma (LGG) in more than 80% of mice (24–26). study highlighted Akt1/3-mediated phosphorylation of an RNA The introduction of Akt1 in conjunction with PDGFB led to only processing regulator, which led to alternative splicing of FGFR2. 16% incidence of high-grade glioma (HGG), which was not statis- Additional studies are reporting potential nuclear functions of tically significant from PDGFB alone. However, when Akt2 or Akt3 Akt3, including Ago2-mediated translational repressive activities was injected with PDGFB, the incidence of HGGs rose to 78% and (28), transcriptional control of IGFBP3 in lung cancer cells (29), 97%, respectively (Fig. 1B), which is significantly higher than andERBB2,ERBB3,andERα in breast tumor cells from a mouse PDGFB alone (P < 0.001, Fisher’sexacttest)andAkt1(P < 0.001, transgenic model (30).
Load more

Recommended publications
  • Selective Targeting of Cyclin E1-Amplified High-Grade Serous Ovarian Cancer by Cyclin-Dependent Kinase 2 and AKT Inhibition
    Published OnlineFirst September 23, 2016; DOI: 10.1158/1078-0432.CCR-16-0620 Biology of Human Tumors Clinical Cancer Research Selective Targeting of Cyclin E1-Amplified High-Grade Serous Ovarian Cancer by Cyclin- Dependent Kinase 2 and AKT Inhibition George Au-Yeung1,2, Franziska Lang1, Walid J. Azar1, Chris Mitchell1, Kate E. Jarman3, Kurt Lackovic3,4, Diar Aziz5, Carleen Cullinane1,6, Richard B. Pearson1,2,7, Linda Mileshkin2,8, Danny Rischin2,8, Alison M. Karst9, Ronny Drapkin10, Dariush Etemadmoghadam1,2,5, and David D.L. Bowtell1,2,7,11 Abstract Purpose: Cyclin E1 (CCNE1) amplification is associated with Results: We validate CDK2 as a therapeutic target by demon- primary treatment resistance and poor outcome in high-grade strating selective sensitivity to gene suppression. However, we found serous ovarian cancer (HGSC). Here, we explore approaches to that dinaciclib did not trigger amplicon-dependent sensitivity in a target CCNE1-amplified cancers and potential strategies to over- panel of HGSC cell lines. A high-throughput compound screen come resistance to targeted agents. identified synergistic combinations in CCNE1-amplified HGSC, Experimental Design: To examine dependency on CDK2 in including dinaciclib and AKT inhibitors. Analysis of genomic data CCNE1-amplified HGSC, we utilized siRNA and conditional from TCGA demonstrated coamplification of CCNE1 and AKT2. shRNA gene suppression, and chemical inhibition using dina- Overexpression of Cyclin E1 and AKT isoforms, in addition to ciclib, a small-molecule CDK2 inhibitor. High-throughput mutant TP53, imparted malignant characteristics in untransformed compound screening was used to identify selective synergistic fallopian tube secretory cells, the dominant site of origin of HGSC.
    [Show full text]
  • Expressed Gene Fusions As Frequent Drivers of Poor Outcomes in Hormone Receptor–Positive Breast Cancer
    Published OnlineFirst December 14, 2017; DOI: 10.1158/2159-8290.CD-17-0535 RESEARCH ARTICLE Expressed Gene Fusions as Frequent Drivers of Poor Outcomes in Hormone Receptor–Positive Breast Cancer Karina J. Matissek1,2, Maristela L. Onozato3, Sheng Sun1,2, Zongli Zheng2,3,4, Andrew Schultz1, Jesse Lee3, Kristofer Patel1, Piiha-Lotta Jerevall2,3, Srinivas Vinod Saladi1,2, Allison Macleay3, Mehrad Tavallai1,2, Tanja Badovinac-Crnjevic5, Carlos Barrios6, Nuran Beşe7, Arlene Chan8, Yanin Chavarri-Guerra9, Marcio Debiasi6, Elif Demirdögen10, Ünal Egeli10, Sahsuvar Gökgöz10, Henry Gomez11, Pedro Liedke6, Ismet Tasdelen10, Sahsine Tolunay10, Gustavo Werutsky6, Jessica St. Louis1, Nora Horick12, Dianne M. Finkelstein2,12, Long Phi Le2,3, Aditya Bardia1,2, Paul E. Goss1,2, Dennis C. Sgroi2,3, A. John Iafrate2,3, and Leif W. Ellisen1,2 ABSTRACT We sought to uncover genetic drivers of hormone receptor–positive (HR+) breast cancer, using a targeted next-generation sequencing approach for detecting expressed gene rearrangements without prior knowledge of the fusion partners. We identified inter- genic fusions involving driver genes, including PIK3CA, AKT3, RAF1, and ESR1, in 14% (24/173) of unselected patients with advanced HR+ breast cancer. FISH confirmed the corresponding chromo- somal rearrangements in both primary and metastatic tumors. Expression of novel kinase fusions in nontransformed cells deregulates phosphoprotein signaling, cell proliferation, and survival in three- dimensional culture, whereas expression in HR+ breast cancer models modulates estrogen-dependent growth and confers hormonal therapy resistance in vitro and in vivo. Strikingly, shorter overall survival was observed in patients with rearrangement-positive versus rearrangement-negative tumors. Cor- respondingly, fusions were uncommon (<5%) among 300 patients presenting with primary HR+ breast cancer.
    [Show full text]
  • GSK3 and Its Interactions with the PI3K/AKT/Mtor Signalling Network
    Heriot-Watt University Research Gateway GSK3 and its interactions with the PI3K/AKT/mTOR signalling network Citation for published version: Hermida, MA, Kumar, JD & Leslie, NR 2017, 'GSK3 and its interactions with the PI3K/AKT/mTOR signalling network', Advances in Biological Regulation, vol. 65, pp. 5-15. https://doi.org/10.1016/j.jbior.2017.06.003 Digital Object Identifier (DOI): 10.1016/j.jbior.2017.06.003 Link: Link to publication record in Heriot-Watt Research Portal Document Version: Peer reviewed version Published In: Advances in Biological Regulation Publisher Rights Statement: © 2017 Elsevier B.V. General rights Copyright for the publications made accessible via Heriot-Watt Research Portal is retained by the author(s) and / or other copyright owners and it is a condition of accessing these publications that users recognise and abide by the legal requirements associated with these rights. Take down policy Heriot-Watt University has made every reasonable effort to ensure that the content in Heriot-Watt Research Portal complies with UK legislation. If you believe that the public display of this file breaches copyright please contact [email protected] providing details, and we will remove access to the work immediately and investigate your claim. Download date: 27. Sep. 2021 Accepted Manuscript GSK3 and its interactions with the PI3K/AKT/mTOR signalling network Miguel A. Hermida, J. Dinesh Kumar, Nick R. Leslie PII: S2212-4926(17)30124-0 DOI: 10.1016/j.jbior.2017.06.003 Reference: JBIOR 180 To appear in: Advances in Biological Regulation Received Date: 13 June 2017 Accepted Date: 23 June 2017 Please cite this article as: Hermida MA, Dinesh Kumar J, Leslie NR, GSK3 and its interactions with the PI3K/AKT/mTOR signalling network, Advances in Biological Regulation (2017), doi: 10.1016/ j.jbior.2017.06.003.
    [Show full text]
  • Characterization of Akt Overexpression in Miapaca-2 Cells
    ANTICANCER RESEARCH 28 : 957-964 (2008) Characterization of Akt Overexpression in MiaPaCa-2 Cells: Prohibitin Is an Akt Substrate both In Vitro and in Cells EDWARD KYU-HO HAN, THOMAS MCGONIGAL, CHRIS BUTLER, VINCENT L. GIRANDA and YAN LUO Abbott Laboratories, Department of R47S, Cancer Research, Global Pharmaceutical Research Division, Abbott Park, IL 60064, U.S.A. Abstract. Akt (PKB) is a serine/threonine protein kinase that is activated by growth factors, cytokines and insulin. that plays an important role in the transduction of signals Activated PI-3K produces PI-3,4,5-P 3 and PI-3,4,-P 2 that affecting apoptosis, cell proliferation and survival. The Akt interact with Akt and recruit Akt from the cytosol to the gene is frequently hyperactivated in tumors and has been plasma membrane. Following membrane localization, Akt is shown to be amplified in a number of types of human phosphorylated at Thr-308 in the T-loop (kinase activation cancers. Furthermore, Akt activity is elevated in cell lines loop) and Ser-473 in the carboxy-terminal tail (hydrophobic with the mutated PTEN tumor suppressor gene. These studies motif). Thr-308 phosphorylation is required for Akt establish Akt as an attractive target for cancer therapy. To activation, while Ser-473 phosphorylation is only needed for determine the roles of Akt1, Akt2 and Akt3 in signal maximal activity. Thr-308 is phosphorylated by 3- transduction, constitutively active Akt1, Akt2 and Akt3 was phophoinositide dependent kinase (PDK1), which is ectopically overexpressed in human pancreatic MiaPaCa-2 activated by PI-3K lipid products (2). cells.
    [Show full text]
  • Cellular Processes Regulating Cytoskeletal
    CELLULAR PROCESSES REGULATING CYTOSKELETAL SIGNALING, INSULIN RESISTANCE AND CALCIUM SIGNALING ARE COMMONLY MISREGULATED IN TYPE 1 AND TYPE 2 MYOTONIC DYSTROPHY PATIENTS by NRIPESH PRASAD A DISSERTATION Submitted in partial fulfillment of the requirements for the Degree of Doctor of Philosophy in The Biotechnology Science and Engineering Program to The School of Graduate Studies of The University of Alabama in Huntsville HUNTSVILLE, ALABAMA 2014 ACKNOWLEDGEMENT The journey we take is supported by many others. Acknowledgement for a few might be just a trifle thing written on a piece of paper. Nevertheless, in the true essence, it gives us an opportunity to remember and express our feelings to those, whom we love, revere and share our secrets. Here I get a great chance to express my token of thanks to people who helped and supported me to complete this journey. It is my sublime duty to express my deepest sense of gratitude and veneration to my advisor Dr. Shawn E. Levy, Director, Genomics Service Lab, HudsonAlpha Institute for Biotechnology for his sincere and indelible inspiration, constant encouragement, constructive criticism, meticulous guidance, sustained interest, immense patience, and supportive nature throughout the investigation of the the research and preparation of this manuscript. I express my deepest sense of reverence and indebtedness to the esteemed members of my Advisory Committee, Dr(s). Joseph Ng, Debra Moriarity, Devin Absher, Gerg Cooper and Luis Cruz-Vera for their valuable suggestions and encouragement at various stages of my research and thesis writing. Sincere regards are due to, Dean, Graduate School, University of Alabama in Huntsville, Huntsville, AL, USA for providing all the necessary help and support.
    [Show full text]
  • Genetic Background of Ataxia in Children Younger Than 5 Years in Finland E444
    Volume 6, Number 4, August 2020 Neurology.org/NG A peer-reviewed clinical and translational neurology open access journal ARTICLE Genetic background of ataxia in children younger than 5 years in Finland e444 ARTICLE Cerebral arteriopathy associated with heterozygous variants in the casitas B-lineage lymphoma gene e448 ARTICLE Somatic SLC35A2 mosaicism correlates with clinical fi ndings in epilepsy brain tissuee460 ARTICLE Synonymous variants associated with Alzheimer disease in multiplex families e450 Academy Officers Neurology® is a registered trademark of the American Academy of Neurology (registration valid in the United States). James C. Stevens, MD, FAAN, President Neurology® Genetics (eISSN 2376-7839) is an open access journal published Orly Avitzur, MD, MBA, FAAN, President Elect online for the American Academy of Neurology, 201 Chicago Avenue, Ann H. Tilton, MD, FAAN, Vice President Minneapolis, MN 55415, by Wolters Kluwer Health, Inc. at 14700 Citicorp Drive, Bldg. 3, Hagerstown, MD 21742. Business offices are located at Two Carlayne E. Jackson, MD, FAAN, Secretary Commerce Square, 2001 Market Street, Philadelphia, PA 19103. Production offices are located at 351 West Camden Street, Baltimore, MD 21201-2436. Janis M. Miyasaki, MD, MEd, FRCPC, FAAN, Treasurer © 2020 American Academy of Neurology. Ralph L. Sacco, MD, MS, FAAN, Past President Neurology® Genetics is an official journal of the American Academy of Neurology. Journal website: Neurology.org/ng, AAN website: AAN.com CEO, American Academy of Neurology Copyright and Permission Information: Please go to the journal website (www.neurology.org/ng) and click the Permissions tab for the relevant Mary E. Post, MBA, CAE article. Alternatively, send an email to [email protected].
    [Show full text]
  • Androgen Receptor
    RALTITREXED Dihydrofolate reductase BORTEZOMIB IsocitrateCannabinoid dehydrogenase CB1EPIRUBICIN receptor HYDROCHLORIDE [NADP] cytoplasmic VINCRISTINE SULFATE Hypoxia-inducible factor 1 alpha DOXORUBICINAtaxin-2 HYDROCHLORIDENIFENAZONEFOLIC ACID PYRIMETHAMINECellular tumor antigen p53 Muscleblind-likeThyroidVINBURNINEVINBLASTINETRIFLURIDINE protein stimulating 1 DEQUALINIUM SULFATEhormone receptor CHLORIDE Menin/Histone-lysine N-methyltransferasePHENELZINE MLLLANATOSIDE SULFATE C MELATONINDAUNORUBICINBETAMETHASONEGlucagon-like HYDROCHLORIDEEndonuclease peptide 4 1 receptor NICLOSAMIDEDIGITOXINIRINOTECAN HYDROCHLORIDE HYDRATE BISACODYL METHOTREXATEPaired boxAZITHROMYCIN protein Pax-8 ATPase family AAA domain-containing proteinLIPOIC 5 ACID, ALPHA Nuclear receptorCLADRIBINEDIGOXIN ROR-gammaTRIAMTERENE CARMUSTINEEndoplasmic reticulum-associatedFLUOROURACIL amyloid beta-peptide-binding protein OXYPHENBUTAZONEORLISTAT IDARUBICIN HYDROCHLORIDE 6-phospho-1-fructokinaseHeat shockSIMVASTATIN protein beta-1 TOPOTECAN HYDROCHLORIDE AZACITIDINEBloom syndromeNITAZOXANIDE protein Huntingtin Human immunodeficiency virus typeTIPRANAVIR 1 protease VitaminCOLCHICINE D receptorVITAMIN E FLOXURIDINE TAR DNA-binding protein 43 BROMOCRIPTINE MESYLATEPACLITAXEL CARFILZOMIBAnthrax lethalFlap factorendonucleasePrelamin-A/C 1 CYTARABINE Vasopressin V2 receptor AMITRIPTYLINEMicrotubule-associated HYDROCHLORIDERetinoidTRIMETHOPRIM proteinMothers X receptor tau against alpha decapentaplegic homolog 3 Histone-lysine N-methyltransferase-PODOFILOX H3 lysine-9OXYQUINOLINE
    [Show full text]
  • Targeting BRAF for Patients with Melanoma
    British Journal of Cancer (2011) 104, 392 – 398 & 2011 Cancer Research UK All rights reserved 0007 – 0920/11 www.bjcancer.com Minireview Targeting BRAF for patients with melanoma ,1,3 2 2,3 H-T Arkenau* , R Kefford and GV Long 1Sarah Cannon Research UK, 93 Harley Street, London W1G 6AD, UK; 2Melanoma Institute Australia and Westmead Hospital, University of Sydney, New South Wales, Australia The prognosis of patients with metastatic melanoma is poor and not influenced by systemic therapy with cytotoxic drugs. New targeted agents directed against the RAS-RAF-MEK-ERK pathway show promising activity in early clinical development and particular interest is focused on selective inhibitors of mutant BRAF, which is present in one half of the cases of metastatic melanoma. The majority of patients on early trials of these drugs develop secondary resistance and subsequent disease progression and it is, therefore, critical to understand the underlying escape mechanisms leading to resistance. British Journal of Cancer (2011) 104, 392–398. doi:10.1038/sj.bjc.6606030 www.bjcancer.com Published online 7 December 2010 & 2011 Cancer Research UK Keywords: BRAF; BRAFV600E; melanoma; PI3K-AKT-mTOR; RAS-RAF-MEK-ERK MELANOMA: A HETEROGENEOUS DISEASE website). The mutations are either in the activating segment in exon 15 or the glycine-rich loop (P-loop) in exon 11 of the kinase Metastases develop in 10–15% of patients with cutaneous domain of the BRAF protein (Figure 2). The point mutation in melanoma and there is no evidence from phase-III trials that DNA (1799T-A) resulting in a single amino-acid substitution at systemic treatment prolongs survival, nor is there an effective Valine 600 to Glutamic acid in the activating segment (V600E, adjuvant therapy after resection of high risk Stage I–III disease previously known as V599E) is the most common change, and is (Thompson et al, 2005).
    [Show full text]
  • Mtorc1 Is Necessary but Mtorc2 and Gsk3b Are Inhibitory for AKT3
    RESEARCH ARTICLE mTORC1 is necessary but mTORC2 and GSK3b are inhibitory for AKT3-induced axon regeneration in the central nervous system Linqing Miao1†, Liu Yang1†, Haoliang Huang1, Feisi Liang1, Chen Ling2, Yang Hu1,3* 1Shriners Hospitals Pediatric Research Center, Temple University Lewis Katz School of Medicine, Philadelphia, United States; 2Division of Cellular and Molecular Therapy, Department of Pediatrics, University of Florida College of Medicine, Gainesville, United States; 3Department of Anatomy and Cell Biology, Temple University Lewis Katz School of Medicine, Philadelphia, United States Abstract Injured mature CNS axons do not regenerate in mammals. Deletion of PTEN, the negative regulator of PI3K, induces CNS axon regeneration through the activation of PI3K-mTOR signaling. We have conducted an extensive molecular dissection of the cross-regulating mechanisms in axon regeneration that involve the downstream effectors of PI3K, AKT and the two mTOR complexes (mTORC1 and mTORC2). We found that the predominant AKT isoform in CNS, AKT3, induces much more robust axon regeneration than AKT1 and that activation of mTORC1 and inhibition of GSK3b are two critical parallel pathways for AKT-induced axon regeneration. Surprisingly, phosphorylation of T308 and S473 of AKT play opposite roles in GSK3b phosphorylation and inhibition, by which mTORC2 and pAKT-S473 negatively regulate axon regeneration. Thus, our study revealed a complex neuron-intrinsic balancing mechanism involving *For correspondence: yanghu@ AKT as the nodal point of PI3K, mTORC1/2 and GSK3b that coordinates both positive and negative temple.edu cues to regulate adult CNS axon regeneration. † These authors contributed DOI: 10.7554/eLife.14908.001 equally to this work Competing interests: The authors declare that no competing interests exist.
    [Show full text]
  • Inhibition of ERK 1/2 Kinases Prevents Tendon Matrix Breakdown Ulrich Blache1,2,3, Stefania L
    www.nature.com/scientificreports OPEN Inhibition of ERK 1/2 kinases prevents tendon matrix breakdown Ulrich Blache1,2,3, Stefania L. Wunderli1,2,3, Amro A. Hussien1,2, Tino Stauber1,2, Gabriel Flückiger1,2, Maja Bollhalder1,2, Barbara Niederöst1,2, Sandro F. Fucentese1 & Jess G. Snedeker1,2* Tendon extracellular matrix (ECM) mechanical unloading results in tissue degradation and breakdown, with niche-dependent cellular stress directing proteolytic degradation of tendon. Here, we show that the extracellular-signal regulated kinase (ERK) pathway is central in tendon degradation of load-deprived tissue explants. We show that ERK 1/2 are highly phosphorylated in mechanically unloaded tendon fascicles in a vascular niche-dependent manner. Pharmacological inhibition of ERK 1/2 abolishes the induction of ECM catabolic gene expression (MMPs) and fully prevents loss of mechanical properties. Moreover, ERK 1/2 inhibition in unloaded tendon fascicles suppresses features of pathological tissue remodeling such as collagen type 3 matrix switch and the induction of the pro-fbrotic cytokine interleukin 11. This work demonstrates ERK signaling as a central checkpoint to trigger tendon matrix degradation and remodeling using load-deprived tissue explants. Tendon is a musculoskeletal tissue that transmits muscle force to bone. To accomplish its biomechanical function, tendon tissues adopt a specialized extracellular matrix (ECM) structure1. Te load-bearing tendon compart- ment consists of highly aligned collagen-rich fascicles that are interspersed with tendon stromal cells. Tendon is a mechanosensitive tissue whereby physiological mechanical loading is vital for maintaining tendon archi- tecture and homeostasis2. Mechanical unloading of the tissue, for instance following tendon rupture or more localized micro trauma, leads to proteolytic breakdown of the tissue with severe deterioration of both structural and mechanical properties3–5.
    [Show full text]
  • PRODUCTS and SERVICES Target List
    PRODUCTS AND SERVICES Target list Kinase Products P.1-11 Kinase Products Biochemical Assays P.12 "QuickScout Screening Assist™ Kits" Kinase Protein Assay Kits P.13 "QuickScout Custom Profiling & Panel Profiling Series" Targets P.14 "QuickScout Custom Profiling Series" Preincubation Targets Cell-Based Assays P.15 NanoBRET™ TE Intracellular Kinase Cell-Based Assay Service Targets P.16 Tyrosine Kinase Ba/F3 Cell-Based Assay Service Targets P.17 Kinase HEK293 Cell-Based Assay Service ～ClariCELL™ ～ Targets P.18 Detection of Protein-Protein Interactions ～ProbeX™～ Stable Cell Lines Crystallization Services P.19 FastLane™ Structures ～Premium～ P.20-21 FastLane™ Structures ～Standard～ Kinase Products For details of products, please see "PRODUCTS AND SERVICES" on page 1～3. Tyrosine Kinases Note: Please contact us for availability or further information. Information may be changed without notice. Expression Protein Kinase Tag Carna Product Name Catalog No. Construct Sequence Accession Number Tag Location System HIS ABL(ABL1) 08-001 Full-length 2-1130 NP_005148.2 N-terminal His Insect (sf21) ABL(ABL1) BTN BTN-ABL(ABL1) 08-401-20N Full-length 2-1130 NP_005148.2 N-terminal DYKDDDDK Insect (sf21) ABL(ABL1) [E255K] HIS ABL(ABL1)[E255K] 08-094 Full-length 2-1130 NP_005148.2 N-terminal His Insect (sf21) HIS ABL(ABL1)[T315I] 08-093 Full-length 2-1130 NP_005148.2 N-terminal His Insect (sf21) ABL(ABL1) [T315I] BTN BTN-ABL(ABL1)[T315I] 08-493-20N Full-length 2-1130 NP_005148.2 N-terminal DYKDDDDK Insect (sf21) ACK(TNK2) GST ACK(TNK2) 08-196 Catalytic domain
    [Show full text]
  • Akt3 and Mutant B-Raf Cooperate to Promote Early Melanoma
    Research Article Akt3 and Mutant V600EB-Raf Cooperate to Promote Early Melanoma Development Mitchell Cheung,1 Arati Sharma,1 SubbaRao V. Madhunapantula,1 and Gavin P. Robertson1,2,3,4,5 Departments of 1Pharmacology, 2Pathology, and 3Dermatology, The Pennsylvania State University College of Medicine; 4The Foreman Foundation for Melanoma Research; and 5The Penn State Melanoma Therapeutics Program, Hershey, Pennsylvania Abstract Increased activity of the PI3K pathway occurs in f70% of spo- radic melanomas due to loss of PTEN and/or increased expression B-Raf is the most mutated gene in melanoma; however, the of Akt3 resulting from elevated gene copy number (5). Highest level mechanism through which it promotes early melanomas V600E of Akt3 activity occur in metastatic melanomas, deregulating remains uncertain. Most nevi contain activated B-Raf apoptotic signaling and promoting chemoresistance, making it an but few develop into melanoma, and expression in melano- attractive therapeutic target for metastatic disease (6–8). Targeting cytes is inhibitory with low protein levels present in surviv- Akt3 decreases tumorigenesis by increasing cellular apoptosis in ing cells, suggesting unknown cooperative oncogenic events advanced stage melanomas, but it is not known whether it plays a are necessary for melanoma development. Because many second independent role in early melanoma development (7, 9). melanomas have V600EB-Raf and active Akt3, it is possible that The MAPK pathway is activated through Ras mutations in 10% these proteins cooperatively facilitate melanocyte transfor- to 15% and B-Raf mutations in f60% of melanomas (10–16). A mation. In this study, Akt3 is shown to phosphorylate V600EB- single-base mutation converting T to A at nucleotide 1,799 of B-Raf, Raf to lower its activity as well as that of the downstream substituting a valine for a glutamic acid at codon 600 (V600E) in mitogen-activated protein kinase (MAPK) pathway to levels exon 15, is the most prominent mutation (12) and is acquired but promoting early melanoma development.
    [Show full text]