Fig. 1.

Honokiol inhibits colorectal cancer growth. A: topological structure of honokiol. B: HCT116, HCT116-CH2, and HCT116-CH3 cells were incubated with increasing doses of honokiol (0–50 μM), and proliferation was determined by hexosaminidase assay at 24 and 48 h. Honokiol inhibited the growth of HCT116 cells. A similar level of inhibition is seen with HCT116-CH2 cells. In contrast, proliferation of HCT116-CH3 cell was not affected to the same level. On the other hand, up to 25 μM honokiol does not inhibit proliferation of FHC normal colonic epithelial cells. Here the cells were incubated with increasing concentrations of honokiol (0–50 μM) for 48 h and then proliferation levels were determined. C: honokiol inhibits colony formation. Cells were treated with increasing doses of honokiol (0–50 μM) for 24 h. Colonies were allowed to form by incubating in regular media containing 10% FBS for an additional 10 days. There was a reduction in colony formation in both cell lines but was more pronounced in HCT116 cells.