We investigated the molecular factors and pathway activation signatures that determine sensitivity to c-MET inhibitors in a panel of glioblastoma and medulloblastoma cells, glioblastoma stem cells, and established cell line-derived xenografts using functional assays, reverse protein microarrays, and in vivo tumor volume measurements, but validation with animal survival analyses remains to be done.
We investigated the effect of HGF/SF on matrix metalloproteinase-2 (MMP-2), membrane type 1 matrix metalloproteinase (MT1-MMP) and tissue inhibitors of metalloproteinases (TIMPs), expressions of c-Met/HGF receptor-positive human glioblastoma cells.
We also showed that Wnt/β-catenin signaling activities in GBM are directly modulated by the addition of ligand-mediated MET activation or MET inhibition.
This translational correlative component to the MET-PET clinical trials can lead to a better understanding of the existing controversies and can enhance our knowledge for future randomization of GBM patients based on their tumor gene signatures to achieve better prognosis and treatment outcome.
This study demonstrates the potential of integrated 11C-MET-PET/MRI for response assessment of GBM and the utility of combined assessment of morphologic and metabolic information with the proposal for assessing relapsed GBM.
This phenomenon is especially common among tumors with PDGFRA amplification: overall, 43% of PDGFRA-amplified GBM were found to have amplification of EGFR or the hepatocyte growth factor receptor gene (MET) as well.
These results indicate the possible existence of multiple mechanisms of MET activation in glioblastomas and that the activation system of proHGF/SF is important in progression of glioblastomas that express endogenous proHGF/SF and require ligand-dependent MET activation.
Rapid radiographic and clinical improvement after treatment of a MET-amplified recurrent glioblastoma with a mesenchymal-epithelial transition inhibitor.
PV-O glioblastomas were associated with lower expression of VEGFC (p = 0.032) than other periventricular locations, whereas MET overexpression remained exceptional.
Previously, it was demonstrated that treatment with cabozantinib (MET/VEGFR2/RET inhibitor) prolonged survival of mice carrying orthotopic patient-derived xenografts (PDX) of the MET-addicted glioblastoma model E98, yet did not prevent development of recurrent and cabozantinib-resistant tumors.
Our studies reveal a novel mechanism to alter the recycling process of MET in glioblastoma cancer cells by promoting the receptor degradation through a proteasome-sensitive and lysosome-dependent pathway through the ligand-independent activation of MET using anti-MET antibodies.
Our data provide new insights into the potential application of miR-144-3p in GBM therapy by targeting MET and then inhibiting the downstream signaling.
Of the five target genes that were enriched in the glioblastoma pathway, in the WikiPathway database, both HRas proto-oncogene, GTPase and MET proto-oncogene, receptor tyrosine kinase target genes of hsa-miR-139-5p, were found to be significantly associated with patient survival.