To evaluate the potentiation of C3aR antagonism by radiotherapy, we compared tumor growth delay ensuing from the combination of a single dose of 5 Gy followed 24 hours later by daily intraperitoneal injection of the C3aR antagonist to treatment arms comprised of radiotherapy only, C3aR antagonist only, and a no-treatment control arm (vehicle only; Fig. 6E). The gene discussed is C3AR1; the disease is neoplasm.