Fig. 7
Anticancer activity of Iren-AuSiO2_Aptamer nanoplatforms on 3D patient-derived breast cancer organoids. Representative images of three breast cancer samples (M23, M41 and M43) stained for A EGFR and B PDGFRβ. In A, the blue arrows indicate EGFR-positive neoplastic cells (M23, moderate membrane expression; M41, mild membrane expression; M43, strong membrane expression); the red arrows indicate EGFR-negative peritumoral stromal cells. Magnification: 10 × , scale bar = 100 μm. In B, the blue arrows indicate PDGFRβ-negative neoplastic cells; the orange arrows indicate PDGFRβ-positive peritumoral stromal cells (M23 and M41, mild cytoplasmic expression; M43, moderate cytoplasmic expression); the green arrows indicate the endothelial cells of vessels (red blood cells are visible inside) positive for PDGFRβ. Magnification: 5 × , scale bar = 50 μm. C (upper) Representative phase-contrast microscopy images of PDCOs obtained by M23, M41 and M43 tumor samples, magnification: 20 × , scale bar = 250 μm; (lower) flow cytometry analyses to confirm the expression of EGFR and PDGFRβ in the three PDCOs. The histogram indicates the geometric mean fluorescence intensity (gMFI) of EGFR and PDGFRβ expressed on PDCOs, calculated using FlowJo software. D Representative confocal images of PDCO.M23, PDCO.M41 and PDCO.M43 incubated with Iren-AuSiO2_CL4, Iren-AuSiO2_Gint4.T, Iren-AuSiO2_CL4_Gint4.T or untargeted Iren-AuSiO2_Scr for 24 h at 37 °C. Nanoparticles and nuclei are displayed in red and blue, respectively. Magnification: 10 × , 2.0 × digital zoom, scale bar = 50 μm. All digital images were captured under the same settings to enable a direct comparison of staining patterns. E Cell viability assay on PDCO.M23, PDCO.M41 and PDCO.M43 treated as indicated. Bars depict mean ± SD of two independent experiments performed in triplicate. **p < 0.01, ***p < 0.001, ****p < 0.001 relative to Iren-AuSiO2_Scr; ##p < 0.01, ###p < 0.001, ####p < 0.0001. No statistically significant variations among Iren-AuSiO2_Scr and untreated were obtained