Our recent studies found that the levels of MDSCs in breast cancer patient peripheral blood are positively associated with tumor progression and TCM decoction Shugan Jianpi Formula (Radix Bupleuri, Radix Paeoniae Alba, Spica Prunellae, Radix Curcumae, Holboellia Fargesii Reaub, Radix Astragali, Radix Notoginseng, and Radix Glycyrrhizae) (SGJP) had an inhibition function in MDSCs proliferation and could prevent MDSCs induced IL-4, IL-13, and TGF-β expression and CD8+T cells apoptosis. This evidence concerns the gene IL4 and breast cancer.