FIGURE 2.

Detection of phosphorylated receptor tyrosine kinases in EVs released to mouse blood from human cancer cell xenografts. Indicated cell lines are representative of brain, epidermal, breast, lung, prostate, pancreatic, and colorectal cancers. Subcutaneous tumors were grown in SCID mice until subjected to terminal blood collection. Plasma EVs were isolated by ultracentrifugation, lysed, and tested for 42 different human phospho-RTKs using the indicated antibody array platform. Notably, several human RTKs, including EGFR, were detected in the circulating blood in the intact, phosphorylated, and EV-associated form (see text for details).