Once activated with IL-33, these granulocytes exert tumor cytotoxic functions through contact-dependent degranulation, involving polarization of eosinophilic effector proteins (eosinophil cationic protein, eosinophil peroxidase, and granzyme B) and convergence of lytic granules to the immunological synapses (51). The gene discussed is IL33; the disease is neoplasm.