Figure 6.

Effect of the natural sesquiterpene β-caryophyllene (50 µM), doxorubicin (20 µM) and their combination compared the control on the levels of phosphorylated H2AX at Ser139 residue (γH2AX) in Mz-ChA-1 cholangiocarcinoma cells (A) and H69 noncancerous cholangiocytes (B). The cells were treated for 2 h and 24 h, then the pellets were harvested for the western blotting analysis. For each experimental condition, the densitometric bar graph (data expressed as mean ± standard error) obtained from at least two independent replicates and a representative western blotting image, showing the expression levels of γH2AX and β-actin used as protein loading control, were displayed. ***p < 0.001 (one-way ANOVA followed by Dunnett’s multiple comparison post-test), significantly higher than the vehicle control (basal level). ^§p < 0.001 (t-Student test), significantly lower than doxorubicin.