After stimulation with various concentrations of BCE (62.5, 125, 250, 500 or 1,000 μg/ml) for 24 and 72 h, tumor cells were analyzed by qRT-PCR or western blot analyses for the expression of the stem cell genes NANOG, POU5F1 and SOX2, respectively. The gene discussed is SOX2; the disease is neoplasm.