IL6 and neoplasm: Considering the inhibitory effect of IL-6 knock-down on PC-3 cell growth in vitro (Figure 1A and 1B; [43, 44]) and in vivo [44, 45], and the importance of IKKε in the regulation of IL-6 secretion in PC, we studied the role of IKKε on PC-3 cell proliferation and tumor formation.