Elevated apoptotic cell population was found in embelin-treated breast cancer cells co-cultured with IL-1β-stimulated hUCMSCs and the apoptotic rate was nearly 30% in MDA-MB-231 cell line, and 40% in MCF-7 and MDA-MB-453 cell lines (Fig. 5b,d,f). The gene discussed is IL1B; the disease is breast cancer.