The percentages of tumor infiltrating Treg and Teff cells 5 days after injection of tumor cells were similar between B6 and MUC1.Tg mice, whereas percentages of tumor infiltrating Treg cells in MUC1.Tg mice were higher than those in B6 mice when the tumor tissues was examined 10 days after injection of tumor cells (Fig. 2A). This evidence concerns the gene MUC1 and neoplasm.