Involvement of Grb2 adaptor protein in nucleophosmin-anaplastic lymphoma kinase (NPM-ALK)-mediated signaling and anaplastic large cell lymphoma growth

J Biol Chem. 2010 Aug 20;285(34):26441-50. doi: 10.1074/jbc.M110.116327. Epub 2010 Jun 16.

Abstract

Most anaplastic large cell lymphomas (ALCL) express oncogenic fusion proteins derived from chromosomal translocations or inversions of the anaplastic lymphoma kinase (ALK) gene. Frequently ALCL carry the t(2;5) translocation, which fuses the ALK gene to the nucleophosmin (NPM1) gene. The transforming activity mediated by NPM-ALK fusion induces different pathways that control proliferation and survival of lymphoma cells. Grb2 is an adaptor protein thought to play an important role in ALK-mediated transformation, but its interaction with NPM-ALK, as well as its function in regulating ALCL signaling pathways and cell growth, has never been elucidated. Here we show that active NPM-ALK, but not a kinase-dead mutant, bound and induced Grb2 phosphorylation in tyrosine 160. An intact SH3 domain at the C terminus of Grb2 was required for Tyr(160) phosphorylation. Furthermore, Grb2 did not bind to a single region but rather to different regions of NPM-ALK, mainly Tyr(152-156), Tyr(567), and a proline-rich region, Pro(415-417). Finally, shRNA knockdown experiments showed that Grb2 regulates primarily the NPM-ALK-mediated phosphorylation of SHP2 and plays a key role in ALCL cell growth.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anaplastic Lymphoma Kinase
  • Binding Sites
  • Cell Proliferation*
  • GRB2 Adaptor Protein / metabolism*
  • Humans
  • Lymphoma, Large-Cell, Anaplastic / pathology*
  • Nuclear Proteins / genetics
  • Nuclear Proteins / metabolism
  • Oncogene Proteins, Fusion / genetics
  • Oncogene Proteins, Fusion / metabolism*
  • Phosphorylation
  • Protein Binding
  • Protein Tyrosine Phosphatase, Non-Receptor Type 11
  • Protein-Tyrosine Kinases / genetics
  • Protein-Tyrosine Kinases / metabolism*
  • Receptor Protein-Tyrosine Kinases
  • Signal Transduction*
  • Translocation, Genetic
  • Tumor Cells, Cultured

Substances

  • GRB2 Adaptor Protein
  • Nuclear Proteins
  • Oncogene Proteins, Fusion
  • nucleophosmin
  • p80(NPM-ALK) protein
  • ALK protein, human
  • Anaplastic Lymphoma Kinase
  • Protein-Tyrosine Kinases
  • Receptor Protein-Tyrosine Kinases
  • Protein Tyrosine Phosphatase, Non-Receptor Type 11