EMP2 and neoplasm: Therefore, to determine if exosomes could be taken up by H2170 cells and if the uptake of exosomes could influence tumor migratory ability, uptake of PKH67-stained vesicles was visualized by confocal microscopy in H2170 cells incubated with EMP2PKH67 (exosome isolated from EMP2 transfectant stained with PKH67), MOCKPKH67 (exosome isolated from mock cells stained with PKH67), PBSPKH67 (PBS stained with PKH67), or a negative control (NTC) which did not contain PKH67 or exosomes.