Fig. 1.

Human RMS cell survival depends upon HSP70 activation. (A) Cell lines were seeded in 96-well plates and treated with increasing MAL3-101, an inhibitor of HSP70 cochaperone activation. Viability at 72 h was measured using a CellTiter-Glo assay; IC₅₀ doses were calculated using nonlinear regression. Data are shown as mean ± SEM (n = 3). (B and C) RMS13 (B) and RD (C) cells were treated with 10 μM MAL3-101 for the indicated times, and whole-cell lysates were blotted for PARP cleavage, PAX3-FOXO1, c-RAF, AKT, and β-actin. Data represent three independent experiments. (D) RMS13 and RD cells were treated with 10 μM MAL3-101 or DMSO, and numbers of viable cells were counted by trypan blue exclusion at the indicated times. The mean percentage (± SEM) of viable cells compared with DMSO is shown (n = 6).