Fig. 5

STAT1 activation triggers NR2F1 expression to sustain dormancy. (A) Western blotting was used to assess downstream signaling pathways activated by apoEVs in CC cells. (B) NR2F1 protein expression was quantified in CC cells treated with shMTA1-apoEVs or shNC-apoEVs. Rescue experiments indicated that silencing STAT1 (siSTAT1) suppressed the increase in NR2F1 expression induced by shNC-apoEVs. (C) NR2F1 protein levels were measured in CC cells treated with 2-NP (a p-STAT1 activator) or F-ara-A (a p-STAT1 inhibitor) via western blotting. (D) A diagram showing the predicted STAT1 binding sites on the NR2F1 promoter. (E) Luciferase activity of the NR2F1 promoter was assessed in CC cells with either p-STAT1 activation or inhibition. (F) ChIP assays were conducted to examine STAT1 enrichment at the STAT1 binding sites (SBSs) in the NR2F1 promoter region, compared to IgG. (G) Glucose consumption was measured in SiHa cells incubated with the indicated EVs, along with 2-NP or F-ara-A, for 48 h. (H-I) Cell cycle progression was analyzed by FACS in SiHa cells treated with the indicated EVs and 2-NP or F-ara-A for 48 h. Radiation sensitivity was evaluated by colony formation assays (J) and apoptosis analysis (K). Inhibition of p-STAT1 signaling significantly reduced colony formation and increased apoptosis in SiHa cells treated with apoEVs