CD4 and breast cancer: For example, SRC-3 inhibition with an SRC-3 small molecular inhibitor (SRC-2 small molecular inhibitor-2 or SI-2) and SRC-3 knockdown in breast cancer cells generates a tumor-suppressive immune microenvironment in tumors by increasing the numbers of tumor-infiltrating cytotoxic immune cells (such as CD4+ and CD8+ T cells and NK (naturalkiller) cells) and Ifng but reducing CD4+Foxp3+ regulatory T (Treg) cells compared to controls.