In colorectal cancer, SPP1+ macrophages highly express complement component 1C chain (C1QC), mannose receptor C type 1 (MRC1), signal transducer and activator of transcription 1 (STAT1), and peroxisome proliferator-activated receptor gamma (PPARG), which are associated with macrophage polarization (51). Here, SPP1 is linked to colorectal cancer.