Figure 1. Hypoxic^EXO enhance sphere formation in EWS cells.

(A) Western blot of HIF-1α in A673 and SK-ES- cells cultured under hypoxia (time points: 0, 6, 24, 48 and 72 hrs.). (B) NanoSight tracking analysis (NTA) of normoxic and hypoxic A673 and SK-ES-1 exosomes showing particle size and relative concentration. (C) Transmission electron micrograph (TEM) of normoxic and hypoxic A673 and SK-ES-1 exosomes. (D) Western blot of TSG101 and CD63 exosome markers and negative control calnexin. α-Tubulin was used as the internal loading control. (E) A673 and SK-ES-1 EWS cells were cultured in normoxic conditions with 20 μg/ml of their respective normoxic and hypoxic exosomes in a sphere assay. Quantification of spheres was performed (magnification, ×10) (Mean ± SEM, n = 3, ^* P ≤ 0.0008, ^** P ≤ 0.003).