Fig 2: M2 TAMs reduce the cytotoxic effects of SOR on HCC cells. A A schematic diagram of transwell HCC cells/M2 TAMs coculture is shown. TAMsCM were generated from U937 cells treated with HCC cells/U937 cells coculture CM for 48 h, and M2 MfsCyto were generated from U937 cells treated with PMA for 24 h followed by IL-4 and IL-10 for 48 h. B After the differentiation from U937 cells into TAMsCM or M2 MfsCyto, cell adhesion in the three cells was observed by bright field microscopy. Magnification: 200 × , scale bar: 100 µm. The bar graph depicts the numbers of adherent cells (mean ± SEM of 5 randomly chosen fields of view). *P < 0.05; ***P < 0.001 vs. U937 cells. C After differentiation, U937 cells, TAMsCM, and M2 MfsCyto were collected and subjected to flow cytometry with double staining for CD68 and CD204. The bar graph depicts the percentages of CD68+/CD204+ cells. **P < 0.01; ***P < 0.001 vs. U937 cells. D After monoculture or coculture with TAMsCM or M2 MfsCyto for 72 h, HepG2 cells were treated with SOR at different concentrations for 48 h. Cell viability was assessed by MTT assay. E After monoculture or coculture with TAMsCM or M2 MfsCyto for 72 h, HepG2 cells were treated with SOR (10 µM) for 48 h, and then apoptosis was measured by flow cytometry with double staining for Annexin V and PI. The bar graphs depict the percentages of apoptotic HepG2 cells. *P < 0.05 vs. control