The methylation level of 15-LOX1 gene was much higher in lung cancer cell line NCI-H23 than that in the normal lung epithelial cell Bet1A (Fig. 5c and Additional file 1: Table S2), indicating that the low expression of 15-LOX1 gene in lung cancer was at least partially due to the methylation regulation. Here, ALOX15 is linked to lung carcinoma.