Figure 9. The KRAS^G12C inhibitor AMG 510 inhibits CD47 signaling and promotes macrophage phagocytosis of tumor cells in vivo.

EGFP-labeled LLC cells were injected via the tail vein into C57BL/6 mice. After tumor formation, mice were administered AMG 510 via oral gavage once a day for 8 days. (A) Representative H&E-stained lung sections. Scale bar: 2 mm. (B) Representative Ki-67 staining of lung sections. Scale bar: 20 μm. (C) Representative CD47 staining of lung sections. Scale bar: 20 μm. (D) Representative immunoblots of CD47 and p-STAT3 in lung tumor cells. (E) Quantitative RT-PCR analysis of miR-34a expression in lung tumors (n = 3). (F) Immunofluorescence staining for CD11b (red), iNOS (purple), and DAPI (blue) in lung tumors showing an increase in macrophage phagocytosis of tumor cells with AMG 510 treatment. Representative images and quantification results (n = 5 mice) are shown. Arrows indicate GFP⁺iNOS⁺CD11b⁺ cells. Scale bar: 50 μm. Original magnification, ×40 (enlarged insets). Data are shown as the mean ± SEM. *P < 0.05 and ***P < 0.001, by unpaired t test (E and F).