Fig. 2: Knockdown of IGF2R induces apoptosis and drug sensitivity in cervical cancer cells.

a Western blot analysis of IGF2R and IGF1R in cervical cancer cell lines. b Transient knockdown of IGF2R and IGF1R in cervical cancer cells. At 144 h after siRNA transfection, both the knockdown levels of the genes (top panel) and cell viability (bottom panel) were analyzed by western blot analysis and cell viability assay, respectively. c Time course analyses of cell growth under IGF2R knockdown (siIGF2R#1: s7219 and siIGF2R#2: HSS105256). d Apoptosis status of cells with IGF2R or IGF1R knockdown. Apoptotic cell populations (Annexin V-FITC⁺) at 144 h after siRNA transfection were analyzed by flow cytometry. Dot plots are shown in Supplementary Fig. S2c. e Total activities of caspase 3 and 7 of IGF2R- or IGF1R-knockdown cells at 144 h after siRNA transfection. f Sensitivity of IGF2R-knockdown cells to cisplatin. At 48 h after siRNA transfection, cells were further exposed to various concentrations of cisplatin for 96 h. The left and right panels show the dose-response curves and IC₅₀ values for cisplatin (CDDP). g Matrigel-based three-dimensional culture assay at 12 days after siRNA transfection. Representative images of colonies and colony size are shown in the top and bottom panel, respectively. a.u.: arbitrary unit. h Spheroid-forming abilities of cells cultured on a non-adherent plate at 12 days after siRNA transfection are detected by live and dead staining (left panel). Green and red staining indicates viable and dead cells, respectively. The cell viability of the cultured spheroids was validated by monitoring their ATP levels (right panel). All the error bars represent the standard deviation of three independent experiments. *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001; t-test with Welch’s correction and Dunnett’s multiple comparisons test. Scale bars represent 100 μm.