Effect of DLLD combined with UTMD on the MMP of BGC-823 cells. Cells were treated with PBS, DOC, DLLD or DLLD plus UTMD for 48 h. (A) MMP assay by staining with JC-1. (B) Western blot analysis of Bcl-2 and Bax expression. Quantified protein levels of (C) Bax and (D) Bcl-2. Values are presented as the mean ± SD (n=5 for each group). *P<0.05 and ***P<0.001 vs. Control. #P<0.05 and ###P<0.001 vs. DOC. &&P<0.01 and &&&P<0.001 vs. DLLD. DOC, docetaxel; DLLD, DOC-loaded lipid microbubble; UTMD, ultrasound-triggered microbubble destruction; MMP, mitochondrial membrane potential.