To provide additional evidence that GSI effects on cell cycle progression are mediated by Jag1-ICD accumulation, we performed FACS analysis in both HT29 (Figure 3E), a CRC cell line not expressing Jagged1 (Supplementary Figure 1B), and the Jag1-silenced HCT15 cell line (Figures 3F–H) upon GSIs and OXP treatment, alone or in combination. This evidence concerns the gene JAG1 and colorectal carcinoma.