ICAM-2 confers a non-metastatic phenotype in neuroblastoma cells by interaction with α-actinin

Oncogene. 2015 Mar 19;34(12):1553-62. doi: 10.1038/onc.2014.87. Epub 2014 Apr 7.

Abstract

Progressive metastatic disease is a major cause of mortality for patients diagnosed with multiple types of solid tumors. One of the long-term goals of our laboratory is to identify molecular interactions that regulate metastasis, as a basis for developing agents that inhibit this process. Toward this goal, we recently demonstrated that intercellular adhesion molecule-2 (ICAM-2) converted neuroblastoma (NB) cells from a metastatic to a non-metastatic phenotype, a previously unknown function for ICAM-2. Interestingly, ICAM-2 suppressed metastatic but not tumorigenic potential in preclinical models, supporting a novel mechanism of regulating metastasis. We hypothesized that the effects of ICAM-2 on NB cell phenotype depend on the interaction of ICAM-2 with the cytoskeletal linker protein α-actinin. The goal of the study presented here was to evaluate the impact of α-actinin binding to ICAM-2 on the phenotype of NB tumor cells. We used in silico approaches to examine the likelihood that the cytoplasmic domain of ICAM-2 binds directly to α-actinin. We then expressed variants of ICAM-2 with mutated α-actinin-binding domains, and compared the impact of ICAM-2 and each variant on NB cell adhesion, migration, anchorage-independent growth, co-precipitation with α-actinin and production of localized and disseminated tumors in vivo. The in vitro and in vivo characteristics of cells expressing ICAM-2 variants with modified α-actinin-binding domains differed from cells expressing ICAM-2 wild type (WT) and also from cells that expressed no detectable ICAM-2. Like the WT protein, ICAM-2 variants inhibited cell adhesion, migration and colony growth in vitro. However, unlike the WT protein, ICAM-2 variants did not completely suppress development of disseminated NB tumors in vivo. The data suggest the presence of α-actinin-dependent and α-actinin-independent mechanisms, and indicate that the interaction of ICAM-2 with α-actinin is critical to conferring an ICAM-2-mediated non-metastatic phenotype in NB cells.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Actins / metabolism*
  • Animals
  • Antigens, CD / chemistry
  • Antigens, CD / genetics
  • Antigens, CD / metabolism*
  • Binding Sites
  • Cell Adhesion
  • Cell Adhesion Molecules / chemistry
  • Cell Adhesion Molecules / genetics
  • Cell Adhesion Molecules / metabolism*
  • Cell Line, Tumor
  • Female
  • Humans
  • Mice
  • Mice, SCID
  • Models, Molecular
  • Mutation
  • Neoplasm Metastasis
  • Neuroblastoma / metabolism
  • Neuroblastoma / pathology*
  • Protein Binding

Substances

  • Actins
  • Antigens, CD
  • Cell Adhesion Molecules
  • ICAM-2 protein, mouse
  • ICAM2 protein, human