ALT Characterization of BCCs and BCDEs and differential protein expression analysis. (A) Characterization workflow. (B) Western blot of BCC extracts confirming characteristic receptor expression and BCC/BCDE extracts for exosome marker expression (Clathrin/Calnexin as quality control for contamination with other extracellular vesicle types). (C) The concentration and distribution of BCDEs were analyzed with the NanoSight NS300 (vertical axis, x107 particles/ml) and by size (horizontal axis, in nanometers [nm]). (D) Quantitative analysis of BCDEs. (E) Representative TEM images of BCDEs. Scale bar = 200 nm. (F) Intersection of significantly dysregulated proteins by subtype in BCCs and BCDEs. Venn diagrams demonstrate the number of commonly significantly upregulated (“UP”) and downregulated (“DOWN”) proteins in intersections for subtype comparisons. (G) Statistical correlations between subtype comparisons in BCCs (columns) and BCDEs (rows).