The IC50 values (inhibition of cell growth at 50%) of elliticine was 0.89 ± 0.07 µg / mL and of doxorobicin was 0.58 ± 0.04 µg / mL toward 4T1 cell growth while those values were 2 - 3 folds higher in our isolated cancer stem cell clones (P<0.05).