In summary, the elevated KDM1A expression in thyroid cancer cells activates the Wnt/β-catenin signaling pathway through down-regulatingits two antagonists, APC2 and DKK1, by demethylating H3K4me1/2 of the APC2 promoter region and the nonhistone substrate HIF-1α, causing the inhibition of APC2 transcription and the activation of the HIF-1α/microRNA-146a/DKK1 axis. The gene discussed is APC2; the disease is thyroid gland carcinoma.