Fig. 2

Dinaciclib shows stronger inhibitory responses than palbociclib in medulloblastoma. (A) Growth rates over 72 h of HD-MB03 cells treated with dinaciclib (top) or palbociclib (bottom) at the indicated concentrations. (B) Representative phase-contrast images of HD-MB03 cells treated with IC50 and 100xIC50 doses of dinaciclib and palbociclib for 72 h. Images were captured at 100 × total magnification. (C) Representative crystal violet staining images of long-term proliferation assay. HD-MB03 cells were treated with the indicated drugs for 9 days and then fixed and stained. On the right, crystal violet quantifications relative to the presented images. (D) Representative crystal violet staining images showing resistant HD-MB03 colonies arising after dinaciclib and palbociclib wash-out over 12 days recovery. Pre-treatments with each drug were carried out over 24 h before wash-out. (E) Percentages of cell viability inhibition of HD-MB03 medullospheres after 72 h treatment with different doses of dinaciclib or palbociclib, calculated as relative to untreated control. Statistical comparisons were performed using an unpaired, two-tailed Student t-test where **P < 0.01; ***P < 0.001. Plotted graphs show mean ± SD (n = 3).