Fig. 6: MAF directly bound to the super enhancer and activated MAGI2 transcription.

A, B MAGI2 expression in different genetic subtypes of MM, in which its expression is the highest in the MAF-positive MM subgroup (data based on CoMMpass, UAMS, Mayo myeloma datasets, GSE4581 and GSE9782). C Correlation analyses were utilized to quantify the association between MAGI2 and MAF expression levels. A potential positive correlation of MAGI2 and MAF gene was found in clinical specimens of MM (GSE4581). D Global protein expression levels of MAGI2 and MAF in a range of MM cell lines. Elevated MAGI2 protein in MM cells was accompanied by high levels of MAF. E, F The ChIP-seq gene tracks represent H3K27ac, H3K4me3, MED1, BRD4, and RNA pol II signals at the MAGI2 gene loci, and MAF binding site locates within the MAGI2-SE loci. G The protein levels of MAGI2 were detected in JJN3 and KMS11 cells transfected with MAF shRNA or Ctrl by western blotting. The expression of β-actin was detected as a protein loading control. H ChIP-qPCR assays against MAF at the predicted genomic binding sites within MAGI2-SE region were presented in JJN3 and MM1.S cells. I Schematic diagram showing SE-driven MAGI2 activation is dependent, at least partially, on oncogenic transcription factor MAF in MM. *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001 by two-sample, two-tailed t-test compared with the control. Error bars indicate the mean ± SEM. Experiments were performed in triplicate.