The Pancreatic Cancer-Initiating Cell Marker CD44v6 Affects Transcription, Translation, and Signaling: Consequences for Exosome Composition and Delivery

Figure 2

CD44v6 and Tspan8 affect recovery of CIC markers in TEX. (a) TEX protein concentrations were determined by Bradford in culture supernatants of wt, CD44v6kd, and Tspan8kd lines; flow cytometry of (b) constitutive Exo marker and (c) CIC marker expression in wt, CD44v6kd, and Tspan8kd TEX; (a-c) mean ± SD of 3 experiments are shown; significant differences between wt and CD44v6kd cells/TEX: , significant differences between wt and Tspan8kd cells/TEX: s; (d) WB of CIC markers in sucrose gradient fractions of PMA-treated wt, CD44v6kd, and Tspan8kd cells. A representative example and the mean ± SD (3 experiments) of relative signal strength evaluated by ImageJ quantification are shown; significant differences between wt and CD44v6kd cells: , significant differences between wt and Tspan8kd cells: s; (e) WB of CD44v6 and Tspan8 in immunoprecipitates with the indicated antibodies in A818.4 wt cell and TEX lysates. A representative example of 3 independently performed experiments is shown (nd: not detected). A CD44v6kd and more strongly a Tspan8kd affect TEX delivery. Expression of constitutive Exo markers is not affected. However, expression of CD44v6- and Tspan8-associated molecules is impaired in CD44v6kd- and Tspan8kd-TEX.