Similarly, in the RF577 model, the levels of the SFRP2 protein were increased in the serum of control tumor-bearing mice (n = 9) compared to non-tumor-bearing mice (32.6 ± 2.64 ng/mL versus 9.30 ± 2.52 ng/mL, respectively; p < 0.01; n = 8, Figure 3B). This evidence concerns the gene SFRP2 and neoplasm.