Figure 4.

Effect of individual drugs on EwS spheroids

(A) Timeline of the assay. Cells are seeded and 24 h later, when EwS spheroids are formed, they are exposed to a specific drug concentration and imaged every 24 h.

(B) Representative images of spheroids over time (4 days), being exposed to different concentrations of either etoposide or cisplatin. Each image is a superposition of bright-field and PI fluorescent channel (shown in magenta), which indicates dead cells.

(C) Viability quantification of EwS spheroids related to drug concentration using the microfluidic protocols. A sigmoidal fit is performed over these data to determine the IC50 value (indicated with a vertical bar in the middle of the sigmoid). The color of plotted dots indicate the measured spheroid radius in micrometers. On the right side of each plot, a boxplot represents the viability of the control group, subjected to either DMSO or NaCl.

(D) Corresponding drug response curves obtained on spheroids in 96 well low-attachment plates.