SHOX2 and cancer: Some TSGs, including GSTP1, MGMT, CDH1, P16, RAR-β2, septin 9 (SEPT9), syndecan 2 (SDC2), cyclin-dependent kinase inhibitor 2A (CDKN2A), and short stature homeobox 2 (SHOX2), have been validated to be silenced through DNA methylation in various types of cancer [3].