Figure 5.

Inhibition of IDO1 in cervical CSCs reduces Notch1 activation. Tumorspheres from HeLa and SiHa cells were dissociated into single cell suspension. (A,B) The tumorsphere cells were transduced with lentiviruses carrying IDO1 specific shRNAs (IDO1#1 or IDO1#2) or control LacZ specific shRNA (LacZ) followed by selection with puromycin (A) or treatment with 20 μM of INCB-024360 for 48 h. The expression of NICD or IDO1 was determined by Western blotting. The insert numbers indicated the relative expression level in comparison to sh-LacZ transduced cells. (C) The putative binding sites of aryl hydrocarbon receptor/aryl hydrocarbon receptor nuclear translocator (AhR/ARNT) (-GCGTG-) in the Notch1 promoter were analyzed by the EPD website and the binding of ARNT to −309 site of Notch1 promoter in HeLa and SiHa tumorsphere cells after the knockdown of IDO1 was analyzed by the ChIP method with an anti-ARNT antibody and quantitated by the qPCR method. ** p < 0.01. All the experiments were repeated three times and data from one experiment were presented.