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. Here, HIF1A is linked to chronic obstructive pulmonary disease.