ABCB1 and obstructive sleep apnea syndrome: As shown by the FITC-conjugated antibody, ABCB1 transporters showed a membrane-located expression pattern in SW620/Ad300 cells (Figure 5), and the incubation of these cells with 3 μM of ORA or OSA for 72 h did not significantly alter the subcellular distribution pattern of ABCB1 when compared to control.