These results suggest that both FOXA1 and NKX2-1 may act as lineage-specific target genes within the 14q amplicon with opposite functions in lung cancer.
FOXA1 is overexpressed as a result of gene amplification in lung cancer, esophageal cancer, ER-positive breast cancer and anaplastic thyroid cancer and is point-mutated in prostate cancer.
The implication of FOXA1 in the epithelial-to-mesenchymal transition via its regulatory network indicates that FOXA1 may play an important role in the initiation of lung cancer metastasis.
In addition, SOX9 was identified as a transcription factor of FOXA1 in lung cancer and involved in affecting the expression of FOXA1 targeted genes-Bcl2, CDKN1B, RPRM and NKX2.
To conclusion, FOXA family showed significant expression differences between cancer and normal tissues, especially lung cancer, and FOXA1, FOXA3 could be promising prognostic biomarkers for lung cancer.