In epithelial cells of gastrointestinal tract, a previous study has shown that CpG promoter hypermethylation of SHP-1 is frequently observed in colorectal cancer cells while demethylating agents such as DNA methyltransferase inhibitor and 5-Aza-2′-deoxycytidine can induce SHP-1 expression to downregulate JAK2/STAT3 signaling [22]. The gene discussed is JAK2; the disease is colorectal cancer.