IL6 and cancer: Since extracellular IL-6 binds to the cell surface receptor glycoprotein 130 (gp130) and consequently activates several cell-survival-related pathways, several studies have investigated the function of IL-6 in promoting chemotherapeutic resistance in various cancers [11, 14, 15]; however, only a few studies have focused on the role of IL-6 produced by stromal cells in the tumor microenvironment [16, 17].