Figure 2.

Enhancement of cetuximab-induced cell killing by ultrasound (US). Cetuximab was used at a concentration of 100 nM and sonication was performed at intensities of 0.5 W/cm² for 1 min. Viability was determined by trypan blue staining assay 24 h after treatment in (A) HSC-3 cells and (B) HSC-4 cells. The data indicate the mean ± standard deviation (SD) and values are representative of more than three different experiments. Values (*) assessed as synergy by two-way factorial analysis of variance (ANOVA); ^*P<0.01. COMB showed a synergistic enhancement in cell killing compared with the other treatments. CNTRL, non-treated; CETU, cetuximab-treated; UST, ultrasound-treated; COMB, combination of cetuximab and US-treated.