Using flow cytometry to compare antibody labeling for B78 cells only, B78 cells incubated in serum from naïve mice (non-tumor bearing, untreated), and B78 cells incubated in serum from mice rendered disease-free with RT + IC + anti-CTLA-4, we observed the presence of endogenous anti-tumor antibodies against B78 in serum from disease-free mice (Figure 1A). This evidence concerns the gene CTLA4 and neoplasm.