EGFR-Targeted Immunotoxin Exerts Antitumor Effects on Esophageal Cancers by Increasing ROS Accumulation and Inducing Apoptosis via Inhibition of the Nrf2-Keap1 Pathway

Figure 4

Treatment with PT resulted in ROS accumulation and caused repression of the Nrf2-Keap1 pathway. (a) KYSE-450 cells were treated with medium alone (control), Pan (10 nM), PT (1 nM), or PT (10 nM) for 10 hours, respectively, and flow cytometry was used to analyze the level of ROS accumulation in cells after DCFH-DA was added to stain the cells. (b) Key signaling molecules in response to treatments with Pan or PT treatment in KYSE-450 cells. Exponentially growing cells were treated with medium alone (−) or containing Pan (10 nM) or PT (10 nM) for 12 h before being analyzed. Then, EGFR, p-EGFR, ERK, p-ERK, Nrf2, and Keap1 were analyzed by western blot. (c) Bar graphic representations of the DCFH-DA fluorescence intensity upon different treatments relative to control. and . (d) Quantification of western blot signal intensity analysis is expressed relative to the β-actin loading control by using the ImageJ software. Data show the mean ± SD (3 independent experiments). .

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