Figure 4. Inhibition of PDGFB enhanced the sensitivity of esophageal squamous cell carcinoma cells to ionizing radiation (IR), a treatment modality that suppressed PDGF-BB-induced migration, and did so by blocking the PI3K/AKT pathway. PDGFB-knockdown in cancer cells showed lower colony formation capacity than control cells after IR (A). In addition, results of the transwell assay suggested that PDGF-BB can promote KYSE30 and KYSE150 cell migration while IR can suppress it (B). Western blot analysis showed that the PI3K/AKT pathway was activated by PDGF-BB, and pretreatment with IR suppressed PDGF-BB-induced phosphorylation of PI3K and AKT in both cell-lines (C). *P < 0.05, **P < 0.01, ***P < 0.001.