ERK Phosphorylation Regulates the Aml1/Runx1 Splice Variants and the TRP Channels Expression during the Differentiation of Glioma Stem Cell Lines

Abstract

The identification of cancer stem cells in brain tumors paved the way for new therapeutic approaches. Recently, a role for the transcriptional factor Runx1/Aml1 and the downstream ion channel genes in brain cancer development and progression has been suggested. This study aimed to explore the expression and the role of Runx1/Aml1, its Aml1b and Aml1c splice variants and the downstream TRPA1 and TRPV1 ion channels in undifferentiated and day-14 differentiated neural stem cells (NSCs and D-NSCs) and glioblastoma stem cells (GSCs and D-GSCs) lines with different proneural (PN) or mesenchymal (MES) phenotype. Gene and protein expression were evaluated by qRT-PCR, cytofluorimetric, western blot and confocal microscopy analyses. Moreover, by western blot, we observed that ERK phosphorylation enhances the Aml1b and Aml1c protein expression during glioma differentiation. Furthermore, the agonists of TRPA1 and TRPV1 channels stimulated apoptosis/necrosis in GSCs and D-GSCs as evaluated by Annexin V and PI staining and cytofluorimetric analysis. Finally, by qRT-PCR, the modulation of Wnt/β catenin, FGF, and TGFβ/SMAD signaling pathways in PN- and MES-GSCs was reported. Overall, our results provide new evidence regarding Runx1/Aml1 isoform overexpression and modulation in TRP channel expression during gliomagenesis, thus offering new directions for glioblastoma therapy.

The mechanism of BUD13 m6A methylation mediated MBNL1-phosphorylation by CDK12 regulating the vasculogenic mimicry in glioblastoma cells

“…CircGLIS3 promoted invasion and tube formation of glioma through Ezrin T567 phosphorylation [ 58 ]. The phosphorylation of ERK Ser-249 and Ser-266 phosphorylation might affect the occurrence of glioma through Aml1/Runx1 [ 59 ]. Ser-436 phosphorylation promoted YAP-mediated GBM proliferation, migration, and invasion [ 60 ].…”

New Insights into TRP Ion Channels in Stem Cells

“…Ramírez-Barrantes et al detected signals of immune-fluorescent TRPV1 in rat NSCs [ 40 ]. Further, TRPV1 has been found expressed in human NSCs and upregulated in differentiated NSCs [ 41 ]. In neural crest-like stem cells from a neonatal mouse epidermis, TRPV1 has been detected and is shown to be activated by capsaicin [ 42 ].…”

“…TRPA1 is also expressed in human MSCs and NSCs, and is upregulated in differentiated NSCs [ 21 , 41 ].…”

“…TRPV1 has been observed in GSCs and is upregulated in differentiated GSCs of proneural-like and mesenchymal-like cells in an ERK-dependent manner [ 41 ]. Nabissi et al have demonstrated that glioblastoma and GSCs selectively express the TRPV1 5′ untranslated region variant 3 (TRPV1V3), where one of four variants is produced by selective splicing of the first exon.…”

“…Research indicates that TRPA1 is expressed in human GSCs and its expression increases during the differentiation of GSCs [ 41 ].…”