To screen for compounds that selectively inhibit the Keap1/Nrf2 pathway, we developed a high‐throughput screening system using a reporter assay in Keap1 mutant human lung cancer A549 cells.13 First, A549 cells with the reporter plasmid for the Nrf2 promoter region, ARE (A549/ARE‐Luc cells) and A549 cells with the reporter plasmid for E‐cadherin promoter (A549/E‐cad promoter‐Luc cells) were constructed for the primary and counter screening, respectively. The gene discussed is KEAP1; the disease is lung cancer.