NKX2-1 and chronic obstructive pulmonary disease: On the other hand, our results also suggest clinical application of HIF1A inhibitors, such as those reported by previous studies including EZN-2968 and CAY10585, which specifically and respectively inhibit HIF1A mRNA expression and protein synthesis/activity without affecting HIF2 (Yu et al., 2017), as potential drugs for inhibiting mucus overproduction in the COPD airways, as well as the application of NKX2-1 gene delivery via viral vector transduction or nanoparticle delivery for activating the capacity of generating more ciliated cells in the COPD bronchial epithelium.