Calpain 2 is required for the invasion of glioblastoma cells in the zebrafish brain microenvironment

Lal, S., La Du, J., Tanguay, R.L., and Greenwood, J.A.
Journal of neuroscience research   90(4): 769-781 (Journal)
Registered Authors
La Du, Jane K., Tanguay, Robyn L.
glioma, invasion, zebrafish, brain, calpain
MeSH Terms
  • Animals
  • Animals, Genetically Modified
  • Brain Neoplasms/metabolism*
  • Brain Neoplasms/pathology*
  • Calpain/metabolism*
  • Cell Line, Tumor
  • Gene Expression Profiling
  • Gene Expression Regulation, Neoplastic/genetics
  • Gene Knockdown Techniques
  • Glioblastoma/metabolism*
  • Glioblastoma/pathology*
  • Green Fluorescent Proteins/genetics
  • Green Fluorescent Proteins/metabolism
  • Humans
  • In Vitro Techniques
  • Neoplasm Transplantation/methods
  • Neovascularization, Pathologic/etiology
  • Neovascularization, Pathologic/pathology
  • Oligonucleotide Array Sequence Analysis
  • Proto-Oncogene Protein c-fli-1/genetics
  • Proto-Oncogene Protein c-fli-1/metabolism
  • RNA, Small Interfering/pharmacology
  • Tumor Cells, Cultured
  • Zebrafish
22183788 Full text @ J. Neurosci. Res.

Glioblastoma is an aggressive primary brain tumor with a 5-year survival rate of less than 5%. The ability of glioblastoma cells to invade surrounding brain tissue presents the primary challenge for the success of focal therapeutic approaches. We previously reported that the calcium-activated protease calpain 2 is critical for glioblastoma cell invasion in vitro. Here, we show that expression of calpain 2 is required for the dispersal of glioblastoma cells in a living brain microenvironment. Knockdown of calpain 2 resulted in a 2.9-fold decrease in the invasion of human glioblastoma cells in zebrafish brain. Control cells diffusely migrated up to 450 µm from the site of injection, whereas knockdown cells remained confined in clusters. The invasion study was repeated in organotypic mouse brain tissues, and calpain 2 knockdown cells demonstrated a 2.3-fold lower area of dispersal compared with control cells. In zebrafish brain, glioblastoma cells appeared to migrate in part along the blood vessels of the host. Furthermore, angiogenesis was detected in 27% of zebrafish injected with control cells, whereas only 12.5% of fish receiving knockdown cells showed the formation of new vessels, suggesting a role for calpain 2 in tumor cell angiogenesis. Consistent with the progression of glioblastoma in humans, transplanted tumor cells were not observed to metastasize outside the brain of zebrafish. This study demonstrates that calpain 2 expression is required for the dispersal of glioblastoma cells within the dynamic microenvironment of the brain, identifying zebrafish as a valuable orthotopic system for studying glioblastoma cell invasion.

Genes / Markers
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Engineered Foreign Genes