To determine which region(s) of TKT promoter is targeted by HMGA1 and hence plays a role in HMGA1-mediated regulation of TKT, sequences including different areas of TKT promoter were cloned and examined for identifying the elements responsive to Sp1/HMGA1 in ESCC cells (Fig. 6D). This evidence concerns the gene SP1 and esophageal squamous cell carcinoma.