Tan IIA was shown to inhibit breast cancer BT-20 cells by inhibiting the expression of PD-L1, cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4), cluster of differentiation 80 [B7-1 (CD80)], and B7-2 (CD86) (Su, 2018). This evidence concerns the gene CD86 and breast cancer.