Fig 1: MEIS1 and EWS-FLI1 directly co-bind super-enhancer regions of APCDD1, (A) Homer Motif Enrichment results of known transcription factor binding motifs enriched at MEIS1 binding regions in A673 cells. (B) Venn diagram displaying the overlap between EWS-FLI1 and MEIS1 peaks in A673 cells. P value was calculated using Fisher's exact test. (C) Integrative Genomics Viewer showing MEIS1, EWS-FLI1, H3K27ac, H3K4me1 and H3K4me3 occupancy in APCDD1 gene in A673 and SKNMC cells as well as primary tumors. Olive and purple bars indicate template regions subjected to ChIP-qPCR experiments. (D-E) Confirmation of selected (D) MEIS1 and (E) EWS-FLI1 binding sites in APCDD1 locus by ChIP-qPCR. NC, negative control. Error bars represent mean ± SD of three replicates (n.s., statistically no significance, *P < 0.05, **P < 0.01, ***P < 0.001). (F–G) Either (F) EWS-FLI1 or (G) MEIS1 was silenced in A673 and SKNMC cells, and antibodies against either (F) MEIS1 or (G) FLI-1 were used to determine the transcription fator change in occupancy at selected regions of APCDD1 by ChIP-qPCR. Error bars represent mean ± SD of three replicates (n.s., statistically no significance, *P < 0.05, **P < 0.01, ***P < 0.001).