IL6 and cancer: Exogenous treatment of IL-6 (100 ng/ml, 72h) significantly stimulated VEGF production from cancer cells (control; 239.4 ± 16.3 pg/1x 105 cells, IL-6; 322.4 ± 11.8 pg/1x105 cells) and the pretreatment of cancer cells with anti-IL-6R antibody significantly inhibited VEGF production (Fig. 3C).