Perturbations in tumor cell transcriptional regulatory network after the inhibition of γ-secretase. (A) Network diagram illustrating tumor cell transcription factor binding motifs (green) overrepresented in differentially accessible promotor regions after γ-secretase inhibition. Target genes are represented by ovals, in which the red fill color corresponds to increased expression after GSI and blue indicates reduced expression. Edges represent the expected transcriptional regulation curated from a database of human transcriptional regulatory networks (TRRUST v2). (B) Pseudobulk normalized frequency of Tn5 insertion events (a measure of chromatin accessibility) for ATAC-seq peaks encompassing the NFKB1 transcription factor binding motif (MA0105.4). Only peaks within 3 kilobases of a known target gene’s promoter that are statistically correlated with its expression are shown. The violin plots to the right of the tracks illustrate the normalized mRNA expression. Complete results of statistical testing are provided in supplemental Table 6. Chr, chromosome.