c-Met signaling induces a reprogramming network and supports the glioblastoma stem-like phenotype

Y Li, A Li, M Glas, B Lal, M Ying… - Proceedings of the …, 2011 - National Acad Sciences
Y Li, A Li, M Glas, B Lal, M Ying, Y Sang, S Xia, D Trageser, H Guerrero-Cázares
Proceedings of the National Academy of Sciences, 2011National Acad Sciences
The tyrosine kinase c-Met promotes the formation and malignant progression of multiple
cancers. It is well known that c-Met hyperactivation increases tumorigenicity and tumor cell
resistance to DNA damaging agents, properties associated with tumor-initiating stem cells.
However, a link between c-Met signaling and the formation and/or maintenance of
neoplastic stem cells has not been previously identified. Here, we show that c-Met is
activated and functional in glioblastoma (GBM) neurospheres enriched for glioblastoma …
The tyrosine kinase c-Met promotes the formation and malignant progression of multiple cancers. It is well known that c-Met hyperactivation increases tumorigenicity and tumor cell resistance to DNA damaging agents, properties associated with tumor-initiating stem cells. However, a link between c-Met signaling and the formation and/or maintenance of neoplastic stem cells has not been previously identified. Here, we show that c-Met is activated and functional in glioblastoma (GBM) neurospheres enriched for glioblastoma tumor-initiating stem cells and that c-Met expression/function correlates with stem cell marker expression and the neoplastic stem cell phenotype in glioblastoma neurospheres and clinical glioblastoma specimens. c-Met activation was found to induce the expression of reprogramming transcription factors (RFs) known to support embryonic stem cells and induce differentiated cells to form pluripotent stem (iPS) cells, and c-Met activation counteracted the effects of forced differentiation in glioblastoma neurospheres. Expression of the reprogramming transcription factor Nanog by glioblastoma cells is shown to mediate the ability of c-Met to induce the stem cell characteristics of neurosphere formation and neurosphere cell self-renewal. These findings show that c-Met enhances the population of glioblastoma stem cells (GBM SCs) via a mechanism requiring Nanog and potentially other c-Met–responsive reprogramming transcription factors.
National Acad Sciences