Integrin α6β4 expression is unique to NSCLC-sEVs.A, Western blot analysis of sEVs (5 μg) prepared from SCC (H520, SK-MES-1, and LK-2), LCC (H1299), LUAD (HCC827), and SCLC (H446 and SBC-3) cells. B, immunoprecipitation (IP) of the integrin α6 subunit from the detergent-solubilized SCC-sEVs. Equal amounts of input, unbound, and bound fractions were analyzed by Western blot. C, Western blot analysis of whole-cell lysates (20 μg) prepared from SCC (H520, SK-MES-1, and LK-2), LCC (H1299), LUAD (HCC827), and SCLC (H446 and SBC-3) cells. Western blots (A and C) are representative images from three independent experiments. LCC, large-cell lung carcinoma; LUAD, lung adenocarcinoma; NSCLC, non–small-cell lung carcinoma; SCC, squamous-cell lung carcinoma; SCLC, small-cell lung carcinoma; sEV, small extracellular vesicle.