EGR4 is a transcription factor, which belongs to the early growth response (EGR) family of immediate early genes.34 Previous study mainly focused on the roles of EGR4 in male infertility and neural development.35, 36 Matsuo et al reported that EGR4 promoted small cell lung cancer cell proliferation,25 but the expression and roles of EGR4 in NSCLC are still unknown. The gene discussed is EGR4; the disease is male infertility.