EGFR and lung cancer: To investigate the molecular link between DUSP22 deletion and increased PD-L1 expression in lung cancer cells, we found that PD-L1 levels decreased significantly in DUSP22-deleted HCC827 cells treated with gefitinib or cabozantinib alone (Fig. 6A), suggesting that the upregulation of PD-L1 due to DUSP22 deletion is mediated through EGFR and c-Met pathways.