SLC40A1+ TAMs exhibited high expression level of the ferroportin gene SLC40A1 (Fig. 2b, c), which promotes the production of pro-inflammatory cytokines such as IL-6 and IL-23 while inhibiting the production of the key inflammatory regulator IL-1β in the TME, leading to the poor prognosis for cancer [43]. Here, SLC40A1 is linked to cancer.