Combination of MS-275 and IFN-λ inhibits cancer proliferation by elevated rate of apoptosis.

<p>(A) U87 cells were cultured in the presence of DMSO, 1 µM MS-275 alone, 100 ng/ml IFN-λ1 alone, or both for the course of 4 d. Cell numbers were manually determined by hemacytometer counting at the indicated time points. (B, F) Cell proliferation of U87 cells or U87 spheroids in 3D culture with indicated treatment were performed using the WST-1 assay, which measures active cellular metabolism. (C) U87 spheroid formation in 3D culture was photographed at day 14 in culture (representative images are shown; 200× magnification). (D–E) Quantification of the relative sizes and numbers of U87 spheroids in (C). (G) Cell cycle analysis was performed in U87 cells with indicated treatment using propidium iodide staining. Numbers in the histogram show fractions (percent) of sub-G1, N, 2N, and polyploidy from left to right. (H) U87 cells with indicated treatment were stained with Annexin V-FITC and 7-AAD. Numbers indicate the percentage of FITC-positive cells (upper left quadrant). FITC, fluorescein isothiocyanate; 7-AAD, 7-Aminoactinomycin. In all panels, data represent the mean and SEM of at least three experiments.