This is significant since hypoxia is one of the important driving characteristics of alterations in TME.[15] Tumor‐derived lactate has been reported to be sufficient to drive M2‐like TAM polarization in HIF‐1α‐dependent manner in TME.[16] Consistent with this, addition of lactic acid induced a prolonged HIF‐1α (but not HIF‐2α) expression in Nampt wild type (WT), but this did not occur in Nampt deletion (KO) macrophages (Figure2A). Here, HIF1A is linked to neoplasm.