In addition, PEC can reduce the expression of VEGF in tumor tissue, reduce the density of microvascular system in tumor tissue, increase the activity of NK cells and cytotoxic lymphocytes (CTL), promote the proliferation of T lymphocytes and B lymphocytes, increase the activity of T lymphocytes, enhance the secretion of splenocyte IL-2, and raise the levels of IgG, IgG2a, and IgG2b in serum. Here, IL2 is linked to neoplasm.