Academic Rank:
Professor, Department of Pediatrics
Associate Member, Department of Pathology and Laboratory Medicine
Affiliation(s):
Child & Family Research Institute
Location:
Child & Family Research Institute

Short Bio:

Reversible protein tyrosine phosphorylation is a prominent mechanism utilized in controlling these signalling pathways: protein tyrosine kinases (PTKs) and protein tyrosine phosphatases (PTPs) co-ordinately determine the tyrosine phosphorylation status and the function of a particular substrate protein. Perturbations of such signalling pathways underlie a variety of pathological conditions. Aberrant tyrosine phosphorylation due to malfunctioning PTKs is well established as the basis of several human diseases, in particular human cancers. It is becoming apparent that defective or deregulated PTPs are likewise critical in the development and progression of some human diseases such as cancer and diabetes. Consequently, PTPs are excellent targets for disease intervention.

Awards & Recognition:
  • Outstanding University Researcher Award 1999/2000, National University of Singapore – 2001
  • MacMillan Distinguished Lecturer, Rutgers University – 2000
  • National Science Award, Singapore – 1995
  • Medical Research Council of Canada Postdoctoral Fellowship – 1986-88
  • Medical Research Council of Canada Studentship Award – 1982-85
Selected Publications
  • Cheng SY, Sun G, Schlaepfer DD, Pallen CJ. Grb2 Promotes Integrin-Induced Focal Adhesion Kinase (FAK) Autophosphorylation and Directs the Phosphorylation of Protein Tyrosine Phosphatase ¦Á by the Src-FAK Kinase Complex. Mol Cell Biol. 2014 Feb;34(3):348-61. doi: 10.1128/MCB.00825-13. Epub 2013 Nov 18. PubMed PMID: 24248601.
  • Meyer DS, Aceto N, Sausgruber N, Brinkhaus H, M¨¹ller U, Pallen CJ, Bentires-Alj M. Tyrosine phosphatase PTP¦Á contributes to HER2-evoked breast tumor initiation and maintenance. Oncogene. 2014 Jan 16;33(3):398-402. doi: 10.1038/onc.2012.585. Epub 2013 Jan 14. PubMed PMID: 23318421.
  • Fam HK, Walton C, Mitra SA, Chowdhury M, Osborne N, Choi K, Sun G, Wong PC, O’Sullivan MJ, Turashvili G, Aparicio S, Triche TJ, Bond M, Pallen CJ, Boerkoel CF. TDP1 and PARP1 deficiency are cytotoxic to rhabdomyosarcoma cells. Mol Cancer Res. 2013 Oct;11(10):1179-92. doi: 10.1158/1541-7786.MCR-12-0575. Epub 2013 Aug 2. PubMed PMID: 23913164.
  • Samayawardhena LA, Pallen CJ.: Protein-tyrosine phosphatase alpha regulates stem cell factor-dependent c-Kit activation and migration of mast cells. J Biol Chem. 2008 Oct 24;283(43):29175-85.
  • Bessette DC, Qiu D, Pallen CJ.: PRL PTPs: Mediators and markers of cancer progression. Cancer Metastasis Rev. 2008 Jun;27(2):231-52.
  • Ye H, Tan YJL, Ponniah S, Takeda Y, Wang SQ, Schachner M, Watanabe K, Pallen CJ, Xiao ZC. (2008) Neural recognition molecules CHL1 and NB-3 regulate apical dendrite orientation in the neocortex via PTPalpha. EMBO J. 27: 188-200.
  • Maksumova L, Wang Y, Wong NK, Le HT, Pallen CJ, Johnson P. (2007) Differential function of PTPalpha and PTPalpha Y789F in T cells and regulation of PTPalpha phosphorylation at Tyr789 by CD45. J Biol Chem. 282:20925-32.
  • Le HT, Maksumova L, Wang J, Pallen CJ. (2006) Reduced NMDA receptor tyrosine phosphorylation in PTPalpha-deficient mouse synaptosomes is accompanied by inhibition of four src family kinases and Pyk2: an upstream role for PTPalpha in NMDA receptor regulation. J Neurochem. 98:1798-809.
  • Chen M, Chen SC, Pallen CJ. (2006) Integrin-induced tyrosine phosphorylation of protein-tyrosine phosphatase-alpha is required for cytoskeletal reorganization and cell migration. J Biol Chem. 281:11972-80.
  • Maksumova L, Le HT, Muratkhodjaev F, Davidson D, Veillette A, Pallen CJ. (2005) Protein tyrosine phosphatase alpha regulates Fyn activity and Cbp/PAG phosphorylation in thymocyte lipid rafts.  J Immunol. 175:7947-56.
  • Le HT, Ponniah S, Pallen CJ.  (2004) Insulin signalling and glucose homeostasis in mice lacking protein tyrosine phosphatase alpha.  Biochem Biophys Res Commun. 6;314(2):321-9.
  • Skelton MR, Ponniah S, Wang DZ, Doetschman T, Vorhees CV, Pallen CJ. (2003) Protein tyrosine phosphatase alpha (PTP alpha) knockout mice show deficits in Morris water maze learning, decreased locomotor activity, and decreases in anxiety. Brain Res. 984: 1-10.
  • Zeng L, Si X, Yu WP, Le TH, Ng KP, Teng RMH, Ryan K, Wang DZM, Ponniah S, Pallen CJ. (2003) PTPalpha regulates integrin-stimulated FAK autophosphorylaiton and cytoskeletal rearrangement in cell spreading and migration. J. Cell. Biol. 160:137-46.
  • Pallen CJ. (2003) Protein tyrosine phosphatase alpha (PTPalpha): A src family kinase activator and mediator of multiple biological effects. Curr. Top. Med. Chem. 7:821-35.
Research:
  • Childhood Cancer & Blood Research
  • Protein tyrosine phosphatases in cell signalling, health, and disease