While many studies have focused on in vivo animal models, fewer in vitro studies investigated the effects of IL-27 on human tumor cell biology, including human melanoma cell lines (Shimizu and others 2006; Yoshimoto and others 2008) and primary tumor cells from patients with leukemia (Canale and others 2011; Zorzoli and others 2012), and showed antiproliferative activity of IL-27. Here, IL27 is linked to leukemia.