These cells co-localize in hypoxic tumor regions and are predicted to engage in direct adhesive interactions (e.g., COL1A1-ITGB1) and paracrine signaling via TGF-β, WNT5A-FZD2, and CCL3-CCR5 axes, promoting recruitment and pro-inflammatory activity of SPP1+ macrophages. This evidence concerns the gene COL1A1 and neoplasm.