ATG4B and chronic obstructive pulmonary disease: A previous report showed that Egr-1 regulates autophagy in cigarette smoke-induced chronic obstructive pulmonary disease, knockdown of Egr-1 inhibits the expression of Atg4B in Beas-2B cells.38 Our recent study also suggests that Egr-1 promotes hypoxia-induced autophagy to enhance chemoresistance.21 These studies suggest that Egr-1 may have a critical role in regulation of autophagy, but the molecular mechanism is still not fully understood.