Macrophages/monocytes increased the MCL growth in vitro and in vivo. MCL cell proliferation was measured by MTT assay after direct (A) or indirect (B) coculture using transwell inserts with CD14⁺ polarized M1-Mφ or M2-Mφ. Mino alone (5 × 10⁶) or Mino + CD14⁺monocytes (5 × 10⁶, 1:1) were implanted subcutaneously into the flank of male NOD/SCID mice, and tumor size (C), tumor weight (D), and body weight (E) were measured (n = 9 mice). (F) Immunofluorescent staining was performed on the MCL + CD14⁺ xenograft tumors using CD68 (green) and CD163/CD80 (red) antibodies. Nuclei were stained with 4′,6-diamidino-2-phenylindole (DAPI) (blue). (G) Immunofluorescent staining was performed on the MCL + CD14⁺xenograft tumors using CD163 (green) and CD80 (red) antibodies. Nuclei were stained with DAPI (blue). Experiments were performed on 3 tumors, and a representative experiment is shown. ***P < .001.