Interestingly, we also show that two of the developmental genes, HOXB2 and ELF3 which increased in COPD BC after treatment with quercetin in vitro, were also significantly increased in the bronchial brushings of COPD patients treated with 2000 mg/day quercetin for 6 months. This evidence concerns the gene HOXB2 and chronic obstructive pulmonary disease.