IL18 and neoplasm: Thus, based on previous studies reporting on the downstream pathways of IL18 and its receptors, in conjunction with NicheNet's speculation, we hypothesized that CCL18+ macrophages secrete IL18 and act on CXCR3+ CD4+ T cell surface receptors to inhibit the downstream pathways of GADD45B and ICAM1 directly or indirectly, dismantling their pro-tumor effects (Fig. 1O).2