Fig. 6

Differential sensitivity of OSCC cell lines, ORL-48, ORL-196 and ORL-204 to bosutinib. a Bosutinib induced apoptosis in OSCC cell lines. ORL-48, ORL-196 and ORL-204 cells were treated with 1 μM of bosutinib for 24, 48 and 72 h followed by Annexin V/PI staining coupled with flow cytometry analysis. The bars represent mean percentage of apoptotic cells ± SE of each cell line of at least two experiments. * denotes p-value < 0.05 relative to control cells. b Bosutinib inhibited the proliferation of OSCC cells as demonstrated by the reduced number of proliferating cells (red stained cells) following 72 h treatment at 1 μM. The blue-stained nuclei represent the total number of cells in a field while the red-stained nuclei represent proliferating cells that have incorporated the EdU label. c OSCC cell proliferation was significantly inhibited by bosutinib with ORL-196 showing the greatest sensitivity (~80% inhibition) followed by ORL-204 (~70% inhibition) and ORL-48 (~50% inhibition) after bosutinib treatment at 1 μM for 72 h. * denotes significance of p-value < 0.05