MAPK6P4 and glioblastoma: To further verify whether the ATG codon of MAPK6P4-ORF12 was functional, pcDNA-ORF and pcDNA-ORF-GFP were constructed and transfected into GBM cells, and the expression of the GFP fusion protein was quantified after 24 h in GBM cells (Fig. S2.1 b).