Fig. 6
ZOT5-1-Me and ZOT5-1-Et induced cell cycle arrest in U-87 MG cells. (A) Decreased proliferation rates of U-87 MG cells after treatment with an increasing concentration (0.95–15.6 µM) of ZOT5-1-Me and ZOT5-1-Et for 1–4 days were evaluated by cell proliferation assay. Proliferation curves allowed for the calculation of population doubling times. (B) ZOT5-1-Me and ZOT5-1-Et induced cell cycle arrest in U-87 MG cells after 48 h treatment as determined by PI staining followed by FACS analysis. Nocodazole (NOC, 200 ng/mL, 18 h) was used as a positive control of G2/M arrest. (C) Representative FACS dot plots after 48 h treatment with ZOTs are presented. FACS dot plots after 24 h treatments are presented in the Supplementary material. (D) ZOT5-1-Me and ZOT5-1-Et evoked changes to proteins regulating cell cycle, including p21 and phosphorylation of p53 (Ser15), in U-87 MG cells after 48 h treatment as evaluated by Western blot (n = 4). The intensity of bands corresponding to proteins was analysed by densitometry. The results are shown as the fold change of protein levels of treated cells vs. control cells (CTRL). β-actin served as a loading control. (E) Representative Western blot images are presented. DMSO was used as a solvent control. Results are presented as bar plots with mean ± SEM; *p < 0.05; **p < 0.01; ***p < 0.001, ns – not statistically significant.
