IL-24 secreted from transfected human embryonic kidney cells (Hek) was shown to elicit apoptosis of various cancer types in vitro[16], [27]–[30] while others reported that this form of IL-24 was unable to alter growth characteristics of cancer cells (Caudell et al., 2002; Pataer et al., 2005; Ramesh et al., 2003). Here, IL24 is linked to cancer.