Fig. 2: In vitro radiosensitization effect of MbO2@Gd-NTs and the synergistic effect between Gd-Tex and O2.
a Hypoxia level of LLC cells after incubating cells with different agents under hypoxic or normoxic conditions. Each group of these experiments (a) was performed on 4 independent samples with similar results (c.f. Supplementary Fig. 6a). Scale bar, 20 μm. b, c Flow cytometry analysis of cellular ROS levels before and after radiotherapy (RT) using X-ray irradiation (total 2 Gy for one time, n = 3 independent samples). The ROS levels were indicated by H2DCFDA fluorescence. d Cellular DNA DSBs examined by the immunofluorescence staining of γ-H2A.X after incubating cells with different agents under hypoxic conditions and treating cells using X-ray irradiation (total 2 Gy for one time). Scale bar, 40 μm. Each group of these experiments (d) was performed on 5 independent samples with similar results (c.f. Supplementary Fig. 6b). e, f Cellular apoptosis was examined by Annexin V-FITC/PI double staining after incubating cells with different agents under hypoxic or normoxic conditions and treating cells using X-ray irradiation (total 2 Gy for one time). Quantification results of cellular apoptosis with X-ray irradiation were shown (f, n = 5 independent samples). g, h In vitro radiosensitization effect examined by colony formation assay. Photographs of colonies (g) and survival fraction (h) of LLC cells. Cells were treated with different agents under hypoxic conditions, and irradiated with X-rays at total doses of 2, 4, 6, or 8 Gy for one time (n = 4 independent samples). Scale bar, 2 cm. i Cell viability examined by CCK-8 assay. Cells were treated with different agents under hypoxic conditions before X-ray irradiation (total 2 Gy for one time, n = 5 independent samples). The data (c, f, h, i) are shown as the mean ± SD. Statistical analysis was performed by a two-tailed unpaired t test (c, f, i). *P < 0.05; **P < 0.01; ***P < 0.001. Source data are provided as a Source Data file.
