Fig. 2. CPM inhibited APEX1/HIF-1α expression in hypoxic LC cells in vitro.

A RT-qPCR analysis of APEX1 and HIF-1α expression in H460 and A549 cells with or without CPM during hypoxia and normoxia. B H460 and A549 cells were treated with CPM and cultured under 1% O₂. HIF-1α and APEX1 protein levels were determined by western blotting. β-Actin was used as a control. C H460 cells were treated with CPM, 10 μM APEX1 inhibitor E3330, and 5 μM LW6 in normoxia and hypoxia. Protein expression of HIF-1α was assessed by western blotting. D Relative expression of CA9, CXCR4, and EPO in H460 cells treated with CPM in normoxia and hypoxia. Data were expressed as mean ± SEM (n = 3). *P < 0.05, **P < 0.01, ***P < 0.001 compared as indicated.