IL6 and gastric cancer: Since expression of IL-6 upregulates SOCS-1, which participates in the negative regulation of the JAK/STAT pathway (Starr et al, 1997; Song and Shuai, 1998; Losman et al, 1999; Schuringa et al, 2000), we further analysed the expression of SOCS-1 in these gastric cancer cell lines.