Fig. 6.
Functional effects of CD24 on osteosarcoma cells. (a and b) CD24 overexpression promotes migration and invasion of MNNG/HOS(a) and MG-63(b) cells. (c and d) Knockdown of CD24 in MNNG/HOS(c) and MG-63(d) cells resulted in a significant decrease in the invasive and migratory capacities. Ten high power fields were selected for comparison. Data are presented as the mean ± standard deviation (***p < 0.001; **p < 0.01; and *p < 0.05). (e) CD24 overexpression promoted proliferation of MNNG/HOS cells and MG-63 cells (t-test, ***p < 0.001; **p < 0.01; *p < 0.05) . (f) Down-regulation of CD24 expression decreased proliferation of MNNG/HOS cells and MG-63 cells(t-test, ***p < 0.001; **p < 0.01; *p < 0.05) (g and h) Knockdown of CD24 reduced the number of sarcospheres formed in MNNG/HOS(g) and MG-63(h) cells. Left panels: light microscopy. right panels: fluorescence microscopy (green fluorescent protein, GFP); ten high power fields were selected for comparison. Data are presented as the mean ± standard deviation (***p < 0.001; **p < 0.01; and *p < 0.05). (i) Representative images of shCD24 and control cell-induced tumour formation at 8 weeks after 1 × 105 cell injection. Top panels: a: The whole image of three-dimensional CT reconstruction. b: Cross section; c: Coronal section; d: Sagittal section. Bottom panels: The corresponding paraffin-embedded tissues were processed for H&E staining (scale bar = 50 µm; magnified: scale bar = 20 µm) (see Table S14 for relevant details). (j) Representative images of shCD24 and control cell-induced lung metastasis at 12 weeks after 1 × 105 cells injection. Top panels: a: In vivo bioluminescence imaging of the mice; b: Lung tissues isolated from the mice (arrows indicate the pulmonary metastases from osteosarcoma); c: In vitro bioluminescence imaging of isolated lung tissues. Bottom panels: H&E staining of corresponding paraffin-embedded lung tissue from mice (scale bar = 200 µm; magnified: scale bar = 50 µm) (see Table S15 for relevant details).