Figure A1.

Comparative analysis of mandelalide A-induced changes in growth and AMPK signaling in human HeLa cervical and U87-MG glioblastoma cells. (A) Concentration-dependent changes in the growth of human HeLa cells and U87-MG glioblastoma cells in response to mandelalide A or vehicle (0.1% DMSO). Antiproliferative effects were calculated using an MTT antiproliferative/viability assay with the viability of vehicle-treated cells defined as 100%. Cells were either untreated (time zero) or exposed to treatment for 72 h. Cell density at the time of treatment is indicated by a dashed black line at 0% growth. Graphs represent mean viability ± S.E. (n = 3 wells per treatment) and curves represent the fit of data points by nonlinear regression analysis to a logistic equation. Curves represent the fit of data from at least three independent comparisons. (B) Immunoblot analysis of AMPK and ACC status in HeLa cervical and U87-MG glioblastoma cells treated with (+) mandelalide A (30 nM or 100 nM) or (−) vehicle (0.1% DMSO) for 30 min or 90 min. Whole cell lysates were collected, processed for western blot and probed with primary antibodies against phospho-AMPK, phospho-ACC, total AMPK, total ACC, LKB1 and GAPDH as indicated. (C) Histograms show the quantification of phospho-AMPK/total AMPK and phospho-ACC/total ACC normalized to GAPDH from three independent experiments. Statistical significance of change relative to vehicle (0.1% DMSO) is indicated as * p < 0.05, ** p < 0.01, **** p < 0.0001.