DOCSLIB.ORG

Targeting the Hedgehog Pathway in Cancer: Current Evidence and Future Perspectives

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Targeting the Hedgehog Pathway in Cancer: Current Evidence and Future Perspectives cells Review Targeting the Hedgehog Pathway in Cancer: Current Evidence and Future Perspectives Daniel Girardi *, Adriana Barrichello, Gustavo Fernandes and Allan Pereira Division of Medical Oncology, Hospital Sírio-Libanês, Brasilia 70200-730, Brazil; [email protected] (A.B.); [email protected] (G.F.); [email protected] (A.P.) * Correspondence: [email protected]; Tel.: +55-619-8108-2130 Received: 27 December 2018; Accepted: 11 February 2019; Published: 12 February 2019 Abstract: The Hedgehog pathway (HhP) plays an important role in normal embryonic development and its abnormal function has been linked to a variety of neoplasms. Recently, the complex mechanisms involved in this pathway have been deciphered and the cross talks with other important pathways involved in carcinogenesis have been characterized. This knowledge has led to the development of targeted therapies against key components of HhP, which culminated in the approval of vismodegib for the treatment of advanced basal cell carcinoma in 2012. Since then, other compounds have been developed and evaluated in preclinical and clinical studies with interesting results. Today, several medications against components of the HhP have demonstrated clinical activity as monotherapies and in combination with cytotoxic treatment or other targeted therapies against mitogenic pathways that are linked to the HhP. This review aims to clarify the mechanism of the HhP and the complex crosstalk with others pathways involved in carcinogenesis and to discuss both the evidence associated with the growing number of medications and combined therapies addressing this pathway and future perspectives. Keywords: Hedgehog; targeted therapy; SMO inhibitor; GLI 1. Introduction The Hedgehog pathway (HhP) plays a fundamental role in embryonic development, tissue patterning, and wound healing [1]. Aberrant functioning of this pathway is related to several congenital abnormalities and the development of cancer in several organs [2,3]. The idea that alterations in the HhP are linked to carcinogenicity came from the discovery of activating mutations in this pathway in patients with basal cell carcinoma (BCC), medulloblastoma and rhabdomyosarcoma [4–7]. These findings led to a better understanding of the pathway and the development of targeted therapies directed against their effectors [8,9]. In this review, we focus on the characterization of the HhP, its relation with other pathways related to the development of cancer and especially on treatment strategies as a way to fight cancer. 2. Characterization of the HhP and Its Relation with Carcinogenesis The HhP is very complex and can be divided into two different pathways: canonical and noncanonical. The canonical HhP is initiated by the release of three ligands named Sonic Hedgehog (SHH), Desert Hedgehog (DHH), and Indian Hedgehog (IHH) [10]. In the absence of these ligands, the 12-pass transmembrane receptor Patched1 (PTCH1) exerts an inhibitory effect on the transmembrane transducer smoothened (SMO) [11]. Binding of Hedgehog ligands to PTCH1 relieves the repression of SMO by PTCH1, which results in the translocation of SMO to the primary cilium. The primary cilium is a membrane-encased protrusion usually described as a single nonmotile cilium present in a variety of vertebrate cells. In humans, for instance, virtually all other cells have a primary cilium, with Cells 2019, 8, 153; doi:10.3390/cells8020153 www.mdpi.com/journal/cells Cells 2019, 8, 153 2 of 20 the exceptionCells 2019, 8, ofx FOR sperm, PEER REVIEW epithelia cells in the bronchi and oviducts, and ependymal cells that2 of line 22 the brain vesicles. The translocation of SMO to the primary cilium, in turn, initiates an intracellular signal cilium, with the exception of sperm, epithelia cells in the bronchi and oviducts, and ependymal cells cascade that promotes the activation of glioma-associated oncogene (GLI) transcription factors [12]. that line the brain vesicles. The translocation of SMO to the primary cilium, in turn, initiates an Thereintracellular are three memberssignal cascade of the that GLI promotes transcription the activation factor family of glioma (GLI1,-associated GLI2 and oncogene GLI3) that (GLI) share a similartranscription DNA-binding factors domain [12]. There [13 are]. Once three members activated of in the the GLI primary transcription cilium, factor GLIs family dissociate (GLI1, GLI2 from the suppressorand GLI3) of fused that share (SUFU), a similar which DNA is- abinding key cytoplasmic domain [13] negative. Once activated regulator in the of theprimary HhP, cilium, and translocate GLIs into thedissociate nucleus from to initiatethe suppresso the transcriptionr of fused (SUFU), program which related is a key to cytoplasmic the HhP (Figure negative1)[ regulator14]. In the of the absence of HHHhP, ligands, and translocate PTCH1 exerts into the a repressive nucleus to effectinitiate on the SMO transcription by preventing program its related accumulation to the HhP in (Figure the primary cilium.1) [14] In. this In the state, absence SMO of is HH not ligands, capable PTCH1 of activating exerts a repressive GLI transcription effect on SMO factors, by preventing which are its bound to SUFUaccumulation and retained in the inprimary the cytoplasm. cilium. In this In state the cytoplasm,, SMO is not capable the degradation of activating of GLI GLI transcription proteins by the factors, which are bound to SUFU and retained in the cytoplasm. In the cytoplasm, the degradation proteasome can occur through phosphorylation by protein kinase A (PKA), casein kinase 1 (CK1) and of GLI proteins by the proteasome can occur through phosphorylation by protein kinase A (PKA), glycogen synthase kinase 3β (GSK3β)[15,16]. casein kinase 1 (CK1) and glycogen synthase kinase 3β (GSK3β) [15,16]. FigureFigure 1. A 1. simplified A simplified model model for for canonical canonical HhP.HhP. ((A) The Hedgehog Hedgehog receptor receptor PTCH1 PTCH1 inhibits inhibits SMO SMO signalingsignaling in the in absencethe absence of of the the Hedgehog Hedgehog ligand,ligand, which turns turns off off the the Hedgehog Hedgehog signaling signaling pathway. pathway. (B) In(B the) In presence the presence of Hedgehog of Hedgehog ligand, ligand, PTCH1 PTCH1 stops stops inhibiting inhibiting SMO,SMO, resulting resulting in in the the translocation translocation of of SMO to the primary cilium. Once activated in the primary cilium, SMO promotes the release of GLI SMO to the primary cilium. Once activated in the primary cilium, SMO promotes the release of GLI from the SUFU, which allows GLI to enter the nucleus to initiate the transcription program related to from the SUFU, which allows GLI to enter the nucleus to initiate the transcription program related to HhP. Dysregulation of the HhP has been associated with carcinogenesis. HhP. Dysregulation of the HhP has been associated with carcinogenesis. In the noncanonical HhP, activation of the GLI transcription factors can occur independently of Inthe the upstream noncanonical components HhP, of activation the HhP by of cross the talk GLI with transcription other signaling factors cascades can occur [16]. Multiple independently cross of the upstreamtalk and synergistic components interactions of the HhP between by cross HhP talkcomponents with other and signalingother important cascades oncogenic [16]. Multiplepathways cross talk andhave synergistic been shown interactions to activate HhP between and have HhP been components implicated andin several other types important of cancer. oncogenic For example, pathways havecross been talk shown between to activate HhP HhPand the and mechanistic have been target implicated of rapamycin in several (mTOR) types ofpathway cancer. has For been example, crossdescribed talk between in esophageal HhP and carcinoma the mechanistic in which target GLI1 of appears rapamycin to be (mTOR)activated pathway by ribosomal has beenprotein described S6 in esophagealkinase 1 carcinoma(S6K1) through in which direct GLI1 phosphorylation appears to be activated at SEr84 by [17] ribosomal. Conversely, protein another S6 kinase study 1 (S6K1) throughdemonstrated direct phosphorylation that V-akt murine at SEr84 thymoma [17]. Conversely,viral oncogene another homolog study 1 demonstrated(AKT1) is a direct that V-akt transcriptional target of GLI1 [18]. murine thymoma viral oncogene homolog 1 (AKT1) is a direct transcriptional target of GLI1 [18]. Cytotoxic agents, such as radiotherapy and cytokines, can also activate and upregulate the Cytotoxic agents, such as radiotherapy and cytokines, can also activate and upregulate the expression of GLI1 independent of canonical pathway activation. For example, tumor necrosis factor expressionalpha (TNF of GLI1-α) and independent interleukin- of1β canonical (IL-1β) can pathway upregulate activation. the expression For example,of GLI1 through tumor the necrosis nuclear factor alphafac (TNF-tor kappaα) and light interleukin-1 chain enhancerβ (IL-1 of activatedβ) can B upregulate cells (NF-κB) the pathway expression in pancreatic of GLI1 and through breast thecancer nuclear factorcells kappa [19,20] light. Interestingly, chain enhancer evidence of activated now shows Bcells that NF (NF--κBκ B)subunit pathway p65 can inpancreatic bind directly and to breastthe GLI1 cancer cellspromoter [19,20]. Interestingly,region, and inhibition evidence of now NF-κB shows decreased that NF-GLIκ1B activity subunit in p65 breast can cancer bind directlycells [20] to. the GLI1Transforming promoter
Load more

Recommended publications
  • Cyclopamine Inhibition of Sonic Hedgehog Signal Transduction Is
    Developmental Biology 224, 440–452 (2000) doi:10.1006/dbio.2000.9775, available online at http://www.idealibrary.com on View metadata, citation and similar papers at core.ac.uk brought to you by CORE Cyclopamine Inhibition of Sonic Hedgehog Signalprovided by Elsevier - Publisher Connector Transduction Is Not Mediated through Effects on Cholesterol Transport John P. Incardona,* William Gaffield,† Yvonne Lange,‡ Adele Cooney,§ Peter G. Pentchev,§ Sharon Liu,¶ John A. Watson,¶ Raj P. Kapur,ሻ and Henk Roelink*,1 *Department of Biological Structure and Center for Developmental Biology and ࿣Department of Pathology, University of Washington, Seattle, Washington 98195; †Western Regional Research Center, ARS, United States Department of Agriculture, Albany, California 94710; ‡Department of Pathology, Rush–Presbyterian–St. Luke’s Medical Center, Chicago, Illinois 60612; §Developmental and Metabolic Neurobiology Branch, NINDS, National Institutes of Health, Bethesda, Maryland 20892; and ¶Department of Biochemistry and Biophysics, University of California at San Francisco, San Francisco, California 94143 Cyclopamine is a teratogenic steroidal alkaloid that causes cyclopia by blocking Sonic hedgehog (Shh) signal transduction. We have tested whether this activity of cyclopamine is related to disruption of cellular cholesterol transport and putative secondary effects on the Shh receptor, Patched (Ptc). First, we report that the potent antagonism of Shh signaling by cyclopamine is not a general property of steroidal alkaloids with similar structure. The structural features of steroidal alkaloids previously associated with the induction of holoprosencephaly in whole animals are also associated with inhibition of Shh signaling in vitro. Second, by comparing the effects of cyclopamine on Shh signaling with those of compounds known to block cholesterol transport, we show that the action of cyclopamine cannot be explained by inhibition of intracellular cholesterol transport.
    [Show full text]
  • Sonidegib for the Treatment of Advanced Basal Cell Carcinoma
    Zurich Open Repository and Archive University of Zurich Main Library Strickhofstrasse 39 CH-8057 Zurich www.zora.uzh.ch Year: 2016 Sonidegib for the treatment of advanced basal cell carcinoma Ramelyte, Egle ; Amann, Valerie C ; Dummer, Reinhard DOI: https://doi.org/10.1080/14656566.2016.1225725 Posted at the Zurich Open Repository and Archive, University of Zurich ZORA URL: https://doi.org/10.5167/uzh-125862 Journal Article Accepted Version Originally published at: Ramelyte, Egle; Amann, Valerie C; Dummer, Reinhard (2016). Sonidegib for the treatment of advanced basal cell carcinoma. Expert Opinion on Pharmacotherapy, 17(14):1963-1968. DOI: https://doi.org/10.1080/14656566.2016.1225725 Sonidegib for the treatment of advanced basal cell carcinoma Egle Ramelyte1,2,MD, Valerie C. Amann1, MD, Reinhard Dummer 1, MD, 1 - Department of Dermatology, University Hospital Zurich, Zurich, Switzerland 2 - Vilnius University, Centre of Dermatovenereology, Vilnius, Lithuania Corresponding author: Reinhard Dummer, MD University Hospital of Zurich Department of Dermatology Gloriastrasse 31 CH-8091, Zürich, Switzerland Phone: 41-44-255-2507 Fax: 41-44-255-8988 E-mail: [email protected] 1 Abstract Introduction. Advanced and metastatic basal cell carcinomas (BCCs) are rare but still present a severe medical problem. These tumors are often disfiguring and impact the quality of life by pain or bleeding. Based on discovery of the hedgehog (Hh) signaling pathway and it’s role in pathogenesis of BCCs, Smoothened (SMO) inhibitors have been developed with Sonidegib being the 2nd in class. It is the only Hh pathway inhibitor investigated in a randomized trial accompanied by pharmacodynamic investigations. Also, the disease assessment criteria applied were more stringent than those used in trials of 1st developed SMO inhibitor – vismodegib, and required annotated photographs, MRI as well as multiple biopsies in case of regression.
    [Show full text]
  • Assessment Report
    25 June 2015 EMA/472165/2015 Committee for Medicinal Products for Human Use (CHMP) Assessment report Odomzo International non-proprietary name: sonidegib Procedure No. EMEA/H/C/002839/0000 Note Assessment report as adopted by the CHMP with all information of a commercially confidential nature deleted. 30 Churchill Place ● Canary Wharf ● London E14 5EU ● United Kingdom Telephone +44 (0)20 3660 6000 Facsimile +44 (0)20 3660 5555 Send a question via our website www.ema.europa.eu/contact An agency of the European Union © European Medicines Agency, 2015. Reproduction is authorised provided the source is acknowledged. Table of contents 1. Background information on the procedure ............................................ 7 1.1. Submission of the dossier ...................................................................................... 7 1.2. Manufacturers ...................................................................................................... 8 1.3. Steps taken for the assessment of the product ......................................................... 8 2. Scientific discussion .............................................................................. 9 2.1. Introduction......................................................................................................... 9 2.2. Quality aspects .................................................................................................. 11 2.2.1. Introduction .................................................................................................... 11
    [Show full text]
  • Australian Public Assessment Report for Odomzo
    Australian Public Assessment Report for Odomzo Proprietary Product Name: Sonidegib Sponsor: Novartis Pharmaceuticals Australia Pty Ltd November 2019 Therapeutic Goods Administration About the Therapeutic Goods Administration (TGA) • The Therapeutic Goods Administration (TGA) is part of the Australian Government Department of Health and is responsible for regulating medicines and medical devices. • The TGA administers the Therapeutic Goods Act 1989 (the Act), applying a risk management approach designed to ensure therapeutic goods supplied in Australia meet acceptable standards of quality, safety and efficacy (performance) when necessary. • The work of the TGA is based on applying scientific and clinical expertise to decision- making, to ensure that the benefits to consumers outweigh any risks associated with the use of medicines and medical devices. • The TGA relies on the public, healthcare professionals and industry to report problems with medicines or medical devices. TGA investigates reports received by it to determine any necessary regulatory action. • To report a problem with a medicine or medical device, please see the information on the TGA website <https://www.tga.gov.au>. About AusPARs • An Australian Public Assessment Report (AusPAR) provides information about the evaluation of a prescription medicine and the considerations that led the TGA to approve or not approve a prescription medicine submission. • AusPARs are prepared and published by the TGA. • An AusPAR is prepared for submissions that relate to new chemical entities, generic medicines, major variations and extensions of indications. • An AusPAR is a static document; it provides information that relates to a submission at a particular point in time. • A new AusPAR will be developed to reflect changes to indications and/or major variations to a prescription medicine subject to evaluation by the TGA.
    [Show full text]
  • Hedgehog Targeting by Cyclopamine Suppresses Head and Neck Squamous Cell Carcinoma and Enhances Chemotherapeutic Effects
    ANTICANCER RESEARCH 33: 2415-2424 (2013) Hedgehog Targeting by Cyclopamine Suppresses Head and Neck Squamous Cell Carcinoma and Enhances Chemotherapeutic Effects CHRISTIAN MOZET*, MATTHAEUS STOEHR*, KAMELIA DIMITROVA, ANDREAS DIETZ and GUNNAR WICHMANN Department of Otolaryngology, Head and Neck Surgery, University of Leipzig, Leipzig, Germany Abstract. Background: The hedgehog signaling pathway prognosis is worse for those with metastatic disease (2). (HH) is involved in tumorigenesis in a variety of human Besides known risk factors (e.g. alcohol and smoking) and malignancies. In head and neck squamous cell carcinomas occupational exposure to other poorly understood factors, the (HNSCC), Hh overexpression was associated with poor entirety of the relevant tumor biology is still unclear. prognosis. Therefore, we analyzed the effect of Hh signaling Mortality rates of HNSCC have remained almost unchanged blockade with cyclopamine on colony formation of cells from for decades, even though the detection of tumor-specific HNSCC samples. Patients and Methods: HNSCC biopsies pathways has developed rapidly and offers a number of new were cultured alone for reference or with serial dilutions of targets in tumor therapy regimes (e.g. the epidermal growth cyclopamine (5-5,000 nM), docetaxel (137.5-550 nM), or factor-receptor, EGFR, and its tyrosine kinases). Proven cisplatin (1,667-6,667 nM) and their binary combinations. standardized concepts of tumor therapy in first- or second- Cytokeratin-positive colonies were counted after fluorescent line protocols are combinations of well-established cytostatic staining. Results: Cyclopamine concentration-dependently drugs such as platinum-derivates like cisplatin, taxanes like inhibited HNSCC ex vivo [(IC50) at about 500 nM]. In binary docetaxel or others (e.g.
    [Show full text]
  • Comprehensive Investigation of Bioactive Steroidal Alkaloids in Veratrum Californicum
    COMPREHENSIVE INVESTIGATION OF BIOACTIVE STEROIDAL ALKALOIDS IN VERATRUM CALIFORNICUM by Matthew West Turner A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Biomolecular Sciences Boise State University December 2019 © 2019 Matthew West Turner ALL RIGHTS RESERVED BOISE STATE UNIVERSITY GRADUATE COLLEGE DEFENSE COMMITTEE AND FINAL READING APPROVALS of the dissertation submitted by Matthew West Turner Dissertation Title: Comprehensive Investigation of Bioactive Steroidal Alkaloids in Veratrum californicum Date of Final Oral Examination: 01 October 2019 The following individuals read and discussed the dissertation submitted by student Matthew West Turner, and they evaluated the student’s presentation and response to questions during the final oral examination. They found that the student passed the final oral examination. Owen M. McDougal, Ph.D. Chair, Supervisory Committee Julia T. Oxford, Ph.D. Member, Supervisory Committee Daniel Fologea, Ph.D. Member, Supervisory Committee Xinzhu Pu, Ph.D. Member, Supervisory Committee The final reading approval of the dissertation was granted by Owen M. McDougal, Ph.D., Chair of the Supervisory Committee. The dissertation was approved by the Graduate College. DEDICATION This dissertation is dedicated to my beloved wife Lindsey, and to my daughter Matilda. Lindsey, thank you for your support, love, and encouragement. Matilda, you are my heart’s darling. iv ACKNOWLEDGMENTS This work was made possible by the monumental effort put forth by those that came before me and those that worked with me to make the progress described in this dissertation. I wish to acknowledge the literature review, initial extraction methods, meticulously detailed record keeping, and plant harvest contribution made by Chris Chandler.
    [Show full text]
  • Vismodegib Resistance in Basal Cell Carcinoma: Not a Smooth Fit
    View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Elsevier - Publisher Connector Cancer Cell Previews Vismodegib Resistance in Basal Cell Carcinoma: Not a Smooth Fit Todd W. Ridky1 and George Cotsarelis1,* 1Department of Dermatology, Perelman School of Medicine, University of Pennsylvania, BRB 1053, 421 Curie Boulevard, Philadelphia, PA 19104, USA *Correspondence: [email protected] http://dx.doi.org/10.1016/j.ccell.2015.02.009 In this issue of Cancer Cell, two complementary papers by Atwood and colleagues and Sharpe and colleagues show that basal cell carcinomas resistant to the Smoothened (SMO) inhibitor vismodegib frequently harbor SMO mutations that limit drug binding, with mutations at some sites also increasing basal SMO activity. Basal cell carcinoma (BCC) of the skin is target, Smoothened (SMO), was subse- to mutations downstream of SMO at the the most common human cancer in lightly quently identified in 2000 (Cooper et al., level of Gli2 or SUFU (a Gli regulator). pigmented individuals. Mutations acti- 1998; Incardona et al., 1998; Taipale By aligning the mutations with a vating the Hedgehog (HH) signaling et al., 2000). That initial work defining recently solved crystal structure of the pathway drive BCC. Secreted HH exerts the SMO-cyclopamine interaction also SMO transmembrane domain, the au- its effects through binding to Patched included the observation that some thors were able to separate the resis- (PTCH), a 12-pass membrane bound re- SMO point mutants driving BCCs not tance-associated mutations into two ceptor, which relieves PTCH inhibitory only increase basal SMO activity, but groups: (1) mutations within or immedi- activity on the downstream heptahelical simultaneously confer cyclopamine resis- ately adjacent to the ligand/drug binding transmembrane protein Smoothened tance.
    [Show full text]
  • The Effects of Inhibiting Hedgehog Signaling Pathways by Using Specific Antagonist Cyclopamine on the Chondrogenic Differentiation of Mesenchymal Stem Cells
    Int. J. Mol. Sci. 2013, 14, 5966-5977; doi:10.3390/ijms14035966 OPEN ACCESS International Journal of Molecular Sciences ISSN 1422-0067 www.mdpi.com/journal/ijms Article The Effects of Inhibiting Hedgehog Signaling Pathways by Using Specific Antagonist Cyclopamine on the Chondrogenic Differentiation of Mesenchymal Stem Cells Xing Wu 1,*, Zheng-Dong Cai 1, Lei-Ming Lou 1 and Zheng-Rong Chen 2 1 Department of Orthopaedics, Shanghai tenth People’s Hospital, Tongji University School of Medicine, Shanghai 200072, China; E-Mails: [email protected] (Z.-D.C.); [email protected] (L.-M.L.) 2 Department of Orthopaedics, Shanghai Zhongshan Hospital, Fudan University School of Medicine, Shanghai 200032, China; E-Mail: [email protected] * Author to whom correspondence should be addressed; E-Mail: [email protected]; Tel.: +86-21-6630-0588; Fax: +86-21-6630-1051. Received: 18 January 2013; in revised form: 5 March 2013 / Accepted: 7 March 2013 / Published: 14 March 2013 Abstract: This study aimed to investigate the effects of cyclopamine, a specific inhibitor of Hedgehog signaling pathways, on the chondrogenic differentiation of mesenchymal stem cells (MSCs). During culture, the experimental groups were treated with cyclopamine and their cell proliferation status was assessed using the MTT test. The extra-bone cellular matrix (ECM) and Collagen II (Col II) was detected by toluidine blue staining and immunohistochemistry of cells. The concentrations of Col II and aggrecan in the culture solution and cytosol were detected using ELISA on the 7th, 14th, and 21st days of cyclopamine induction. Gene and protein expression of Col II and aggrecan were analyzed on the 14th day of cyclopamine induction using real-time PCR and western blot analyses.
    [Show full text]
  • VIEW Open Access Targeting Hedgehog Signaling in Myelofibrosis and Other Hematologic Malignancies Raoul Tibes* and Ruben a Mesa
    Tibes and Mesa Journal of Hematology & Oncology 2014, 7:18 http://www.jhoonline.org/content/7/1/18 JOURNAL OF HEMATOLOGY & ONCOLOGY REVIEW Open Access Targeting hedgehog signaling in myelofibrosis and other hematologic malignancies Raoul Tibes* and Ruben A Mesa Abstract Treatment of myelofibrosis (MF), a BCR-ABL–negative myeloproliferative neoplasm, is challenging. The only current potentially curative option, allogeneic hematopoietic stem cell transplant, is recommended for few patients. The remaining patients are treated with palliative therapies to manage MF-related anemia and splenomegaly. Identification of a mutation in the Janus kinase 2 (JAK2)gene(JAK2 V617F) in more than half of all patients with MF has prompted the discovery and clinical development of inhibitors that target JAK2. Although treatment with JAK2 inhibitors has been shown to improve symptom response and quality of life in patients with MF, these drugs do not alter the underlying disease; therefore, novel therapies are needed. The hedgehog (Hh) signaling pathway has been shown to play a role in normal hematopoiesis and in the tumorigenesis of hematologic malignancies. Moreover, inhibitors of the Hh pathway have been shown to inhibit growth and self-renewal capacity in preclinical models of MF. In a mouse model of MF, combined inhibition of the Hh and JAK pathways reduced JAK2 mutant allele burden, reduced bone marrow fibrosis, and reduced white blood cell and platelet counts. Preliminary clinical data also suggest that inhibition of the Hh pathway, alone or in combination with JAK2 inhibition, may enable disease modification in patients with MF. Future studies, including one combining the Hh pathway inhibitor sonidegib and the JAK2 inhibitor ruxolitinib, are underway in patients with MF and will inform whether this combination approach can lead to true disease modification.
    [Show full text]
  • The Evolution of Sensory and Neurosecretory Cell Types in Bilaterian Brains
    The evolution of sensory and neurosecretory cell types in bilaterian brains DISSERTATION zur Erlangung des Doktorgrades der Naturwissenschaften Doctor rerum naturalium (Dr. rer. nat.) dem Fachbereich Biologie der Philipps-Universität Marburg vorgelegt von Dipl.-Biol. K. G. Kristin Teßmar–Raible aus Görlitz Marburg/ Lahn 2004 Vom Fachbereich Biologie der Philipps-Universität Marburg als Dissertation am angenommen. Erstgutachterin: Prof. Dr. Monika Hassel Zweitgutachterin : Prof. Dr. Renate Renkawitz-Pohl Tag der mündlichen Prüfung: The evolution of sensory and neurosecretory cell types in bilaterian brains To my parents and my husband for their encouragement and patience Acknowledgements I am very thankful to the following persons in Marburg and Heidelberg that made this study possible: Dr. Monika Hassel at Marburg University for the supervision of my PhD thesis and correction of the text; Dr. Detlev Arendt at the EMBL in Heidelberg for giving me the opportunity to spend time in his lab as a guest and for scientific advice; Dr. Monika Hassel, Dr. Renate Renkawitz-Pohl and the other members of my defense committee for reviewing this thesis. I want to acknowledge all members and guests of the Arendt lab, in particular Sebastian Klaus, Heidi Snyman, and Patrick Steinmetz, for for their help, their useful critical comments, and the interesting scientific discussions; in addition, I want to thank Heidi Snyman for very reliable practical help, especially with degenerated PCRs, minipreps, and restriction digests; and Dr. Detlev Arendt for minipreps of the Pdu-barH1 cloning. Moreover, I thank Dr. Florian Raible and Dr. Detlev Arendt for extensive critical feedback on previous versions of this text.
    [Show full text]
  • The Hedgehog Signaling Pathway in Cancer
    Published OnlineFirst June 19, 2012; DOI: 10.1158/1078-0432.CCR-11-2509 Clinical Cancer Molecular Pathways Research Molecular Pathways: The Hedgehog Signaling Pathway in Cancer Ross McMillan and William Matsui Abstract The Hedgehog (Hh) signaling pathway regulates embryonic development and may be aberrantly activated in a wide variety of human cancers. Efforts to target pathogenic Hh signaling have steadily progressed from the laboratory to the clinic, and the recent approval of the Hh pathway inhibitor vismodegib for patients with advanced basal cell carcinoma represents an important milestone. On the other hand, Hh pathway antagonists have failed to show significant clinical activity in other solid tumors. The reasons for these negative results are not precisely understood, but it is possible that the impact of Hh pathway inhibition has not been adequately measured by the clinical endpoints used thus far or that aberrancies in Hh signal transduction limits the activity of currently available pathway antagonists. Further basic and correlative studies to better understand Hh signaling in human tumors and validate putative antitumor mechanisms in the clinical setting may ultimately improve the success of Hh pathway inhibition to other tumor types. Clin Cancer Res; 18(18); 4883–8. Ó2012 AACR. Background and GLI3 represses Hh target genes that include GLI1, PTCH1 Cyclin D1 c-Myc Bcl-2 The Hedgehog (Hh) signaling pathway is highly con- , , , and , whereas GLI2 can act served from flies to humans and is essential for develop- in either a positive or negative manner depending on ment of the normal embryo (1, 2). In mammals, Hh posttranscriptional and posttranslational processing events signaling regulates both patterning and polarity events (4).
    [Show full text]
  • (IPI-926) Increases Lifespan in a Mouse Medulloblastoma Model
    Hedgehog pathway inhibitor saridegib (IPI-926) increases lifespan in a mouse medulloblastoma model Michelle J. Leea,b,1, Beryl A. Hattona,1, Elisabeth H. Villavicencioa,c, Paritosh C. Khannad, Seth D. Friedmand, Sally Ditzlera, Barbara Pullara, Keith Robisone, Kerry F. Whitee, Chris Tunkeye, Michael LeBlancf, Julie Randolph-Habeckerg, Sue E. Knoblaughg, Stacey Hansena, Andrew Richardsa, Brandon J. Wainwrighth, Karen McGoverne, and James M. Olsona,b,c,2 aClinical Research Division, fPublic Health Sciences Division, gComparative Medicine, Fred Hutchinson Cancer Research Center, Seattle, WA 98109; bNeurobiology and Behavior Program, Departments of dRadiology and cPediatrics, University of Washington and Seattle Children’s Hospital, Seattle, WA 98105; eInfinity Pharmaceuticals, Cambridge, MA 02139; and hDivision of Molecular Genetics and Development, Institute for Molecular Biosciences, University of Queensland, Brisbane QLD 4072, Australia Edited by Dennis A. Carson, University of California at San Diego, La Jolla, CA, and approved April 4, 2012 (received for review September 13, 2011) The Sonic Hedgehog (Shh) pathway drives a subset of medullo- drug resistance (4–6). It remains to be determined whether these blastomas, a malignant neuroectodermal brain cancer, and other drugs confer a survival benefit to medulloblastoma patients. The cancers. Small-molecule Shh pathway inhibitors have induced tu- identification of Smo inhibitors that remain active against cells mor regression in mice and patients with medulloblastoma; how- that develop resistance to other agents in this class could benefit ever, drug resistance rapidly emerges, in some cases via de novo patients, particularly if acquired resistance is limited or slower mutation of the drug target. Here we assess the response and to develop.
    [Show full text]