IL6 and synovial sarcoma: LPS can activate multiple types of immune cells among mouse splenocytes to secret proinflammatory factors including IL6 and IL12, two proinflammation cytokines essential for SS progression and highly produced by activated helper T cells and APCs, respectively [30, 31], as indicated by ELISA (Figures 2(d) and 2(e), P < 0.05, n = 3).