Fig. 3: Inhibition of KDM4C with SD70 impairs cell proliferation and radioresistance in lung cancer in vitro and in vivo.

a, b The inhibition efficacy of SD70 is time and concentration-dependent (n = 3). c SPC-A1 and H460 cells were treated with SD70 (3 μM) for 24 h and 48 h, respectively. Cells were then seeded and cultured for 2 weeks. The colonies were stained using crystal violet solution and then counted. Representative pictures are shown. **P < 0.01, ***P < 0.001 (n = 3). d Inhibition of KDM4C using indicated doses of SD70 impairs tumor growth in lung cancer in vivo (n = 5 mice for each group). ***P < 0.001. e Changes in body weight of xenografts post-inoculation were represented. f Neutral comet assay shows the effect of SD70 treatment on tail formation. The olive tail moment was quantified and graphed. ***P < 0.001 (n = 3). Scale bar, 20 μm. g Quantification of Rad51 foci intensity in SPC-A1 and H460 cells after treatment with SD70. Representative images are shown. Scale bar, 10 μm. ***P < 0.001 (n = 3). h The effects of SD70 treatment on the radiosensitivity of lung cancer cells were determined by clonogenic survival assay. **P < 0.01, ***P < 0.001 (n = 3). i Schematic representation of the xenograft study design and experimental workflow. j Growth curves of xenograft tumors in each group. Mice were treated with SD70 at the concentration of 10 mg/kg (n = 8 mice for each group). ***P < 0.001. k Kaplan–Meier analysis of mice survival due to treatments in (j).