Fig. 9

Validation of the MYC function as a transcription factor of circRRM2 and a positive feedback loop of circRRM2/IGF2BP1/MYC. A Schematic of transcription factor binding sites of the circRRM2 promoter. qRT-PCR results of circRRM2 level in BT-549 cells after silencing JUNB (B), MYC (C), or CTCF (D). BC cells were tested to determine their migration ability in scratch wound healing assays after silencing JUNB (E/H), MYC (F/I), or CTCF (G/J). The relative expression of circRRM2 after silencing IGF2BP1 in BT-549 (K) or MDA-MB-231 (L) cells. The relative expression of JUNB (M), MYC (N), or CTCF (O) after silencing IGF2BP1 in BT-549 cells. P CoIP and WB experiments to detect the binding of MYC to IGF2BP1. Q Diagram illustrating the proposed mechanism of positive feedback loop of circRRM2/IGF2BP1/MYC. *P < 0.05, **P < 0.01, ***P < 0.001