Figure 1. Characterization and comparison of primary mammosphere-derived EVs cultured with or without hormone treatments.

(A) Representative cryo-electron micrographs (Bar, 100 nm). (B) Normalized representation of size distribution by NTA analysis of EVs in one primary breast epithelial cell preparation. Mean, SD and particle concentration values are indicated in the table (EtOH in green, E2 in orange and TAM in light green). (C) Western blot analysis of cell extracts and EVs derived from mammospheres treated with ethanol (EtOH), estrogen (E2) or tamoxifen (TAM). Antibodies against exosomes (Flotillin-1, CD63, CD81 and MFGE8), early (EEA1) and recycling (Rab11) endosomes, or endoplasmic reticulum (Grp78) protein markers were assayed. The molecular mass (kDa) for each protein is indicated.