CCL18 and lung cancer: USP17 could be induced by cytokines secreted from macrophages because various cytokines, including TNF-α, IL-1β, IL-4, IL-6, IL-8, IL-10, CXCL12, CCL18, and CCL22, were able to induce USP17 expression in H1299 and D121 lung cancer cells (Supplementary Figure 2a, b).