Model for the role of soluble and exosomal BAG6 in NK cell activation and anti-tumor immunity. Cells release BAG6-exosomes in response to cellular stress to alert the NK cells to the dangerous cells. Activation of NK cells through released exosomes triggers target cell recognition and killing. Failure of NK cell activation in combination with the release of soluble ligands, including BAG6 inhibits NK cell function leading to immune evasion of the tumor cells from NK cell attack. MVB, multivesicular bodies.