KCNK4 and thyroid cancer: Data in the GEPIA database and the UALCAN database revealed that mRNA expression of KCNK1 (p<1E-12), KCNK5 (p = <1E-12), KCNK6 (p = 2.09930000050207E-08), KCNK7 (p = 3.44069217561582E-12), and KCNK15 (p<1E-12) were significantly higher in thyroid cancer tissues than that in normal tissues, while KCNK2 (p = 1.62614366416847E-12), KCNK4 (p = 4.35290000000421E-06), KCNK9 (p = 2.136300E-03), KCNK16 (p = 1.219450E-04) and KCNK17 (p = 1.829970E-02) mRNA levels were decreased compared to normal tissues (Figure 1).