We confirmed that the differences in tumor cell proliferation was not the result of E4-EC accelerated death due to Jag1 silencing by examining DNA synthesis in E4-ECs by EdU incorporation assay and found that DNA synthesis (S phase) decreased in E4-ECsJag1KD co-cultured with MDA-231 cells (Figure S2A). This evidence concerns the gene JAG1 and neoplasm.