IL33 and cancer: It was also reported by Pisani et al., in contrast to the studies above, that IL-33 appears to have a dichotomic role, being antiproliferative and proapoptotic in cancer cell lines while stimulating proliferation and reducing apoptosis in normal epithelial cell lines [45]; these effects may be mediated by the modulation of the expression of pro-proliferative cell cycle genes involved in G0/G1 and G2/M checkpoints [45] (Figure 2).