a homeobox transcription factor expressed in thyroid, lung, and parts of the brain. Essential for the branching morphogenesis of the lung. Binds and activates the promoters of CEACAM6, thyroid-specific genes, ROR1, LAMP3, VEGF, etc. Its transcription is responsive to SMAD2 signaling after endodermal differentiation is induced in embryonic stem cell. Defects in NKX2-1 are associated with neurological, thyroid, and respiratory problems. Frequent amplified in human lung cancer cell lines and tumors. Amplified in 15% of non-small cell lung cancers (NSCLC), and appears to drive cancer cell proliferation and survival. EGFR may be a downstream effector of NKX2-1 when amplified in NSCLC. May operate as a lineage-specific oncogene in lung adenocarcinoma. Belongs to the NK-2 homeobox family. Forms a regulatory loop with GRHL2 that coordinates lung epithelial cell morphogenesis and differentiation. Activates the transcription of GNRHR and plays a role in enhancing the circadian oscillation of its gene expression. Represses the transcription of the circadian transcriptional repressor NR1D1. Belongs to the NK-2 homeobox family. 2 isoforms of the human protein are produced by alternative splicing. Note: This description may include information from UniProtKB.