TNF and breast cancer: PRKCI is elevated in cytotoxic neutrophils and can be stimulated by TNF in neutrophils with low basal levels of PRKCI. Our findings suggest that the cytokine profiles of breast cancer patients may be indicative of the cytotoxicity of the patient’s neutrophils, and raise the possibility of novel immunotherapies whereby patient neutrophils are treated with select cytokines to stimulate anticancer cell cytotoxicity, both of which may prove helpful for the clinical management of breast cancer patients.