Figure 13.

Representative immunofluorescence (IF) images and semiquantitative analysis of the phosphorylated STAT3 on tyrosine 705 residue induced by the natural sesquiterpene β-caryophyllene (50 µM), doxorubicin (20 µM) and their combination compared the control in Mz-ChA-1 cholangiocarcinoma cells and H69 noncancerous cholangiocytes. After treatments of 24 h, the cells were fixed then stained with a specific anti-phospho(Tyr705)-STAT3 primary antibody to assess the protein phosphorylation rate, as shown by the yellow arrows. The semiquantitative analysis has been carried out (four fields for each treatment) applying a previous published grading system [64]: 0%–5% = negative; 6%–10% = +/−; 11%–30% = +; 31%–60% = ++; > 61% = +++.