To investigate the contribution of neutrophils to tumor development in our model, we depleted neutrophils by systemic administration of an anti-Ly6G (or an IgG isotype control) in Casp8−/− mice for 8 wk, starting 2 wk after initiation of 4NQO treatment (Fig. 5 A and B). The gene discussed is CASP8; the disease is neoplasm.