The effect of machilin D on the expression of CSC marker proteins and mammosphere growth. (A) Immunoblot analysis of the Nanog, c-Myc, Oct4, and Sox2 proteins in the mammospheres after treatment with machilin D for two days. (B) Machilin D inhibits mammosphere growth. Mammospheres with/without machilin D were dissociated into single cells and plated in 6 cm dishes in equal numbers. One, two, and three days later, the cells were counted. (C) The proposed model of CSC death through the NF-κB inhibition and IL-6 and IL-8 signaling pathways by machilin D is shown. The data from triplicate experiments are represented as the mean ± SD. ***p < 0.05 versus the DMSO-treated control group indicated significant differences.