Furthermore, a high rate of methylation was detected on several SOCS genes, such as SOCS1 in hepatocellular carcinoma (Okochi et al., 2003), SOCS3 in head and neck squamous cell carcinoma (Weber et al., 2005), and SOCS6 in GC (Lai et al., 2010). Here, SOCS3 is linked to head and neck squamous cell carcinoma.