Fig. 5: Treatment of human OS cell lines with Enzalutamide displays an inhibitory effect on the activity of ALDH.

A Enzalutamide was used at fold dilutions starting at 100 µM. Dose-response curve of enzalutamide fold dilutions on C4-2, SaOS-2, and SaOS-LM2. The IC₅₀ concentrations of enzalutamide are 98.46 µM 109.7 µM (SaOS-LM2 and SaOS-2 respectively). C4-2 served as a positive control. B Human OS cells (SaOS-2 and SaOS-LM2) were cultured in 3 conditions (control: no enzalutamide, 48-h enzalutamide exposure, and 72 enzalutamide exposure), with 6 replicates per condition, and harvested for Aldeflour Assay analysis for ALDH activity using Flow Cytometry. Collected cells in each condition were gated base on ALDH activity. SaOS-2 displayed a constant decrease in ALDH activity at both drugging time points. SaOS-LM2 displayed an initial decrease in ALDH activity after 48 h of drug exposure but showed a slight rebound increase in ALDH activity at the 72-h time point. C Median ALDH activity is displayed in overlayed fluorescence graphs for all conditions and cell lines. For both cell lines, longer exposure to enzalutamide presented with a decrease in ALDH activity. D ALDH activity is displayed in a bar graph by compiling the median ALDH activity from all respective biological replicates. In SaOS-2, again, there is significant decrease in ALDH activity when comparing 48-h and 72-h drug exposure to untreated control. In SaOS-LM2, there is a significant decrease in ALDH activity in the 48-drug exposure time point, with an observed slight increase in ALDH activity at the 72-h time point. The statistical significance among the different treatment time points in the Aldefluor activity assay was calculated using two-tailed Student’s unpaired t-test. Data represent mean ± SD: *p < 0.05; **p < 0.01; ***p < 0.001.