ICOSLG and breast cancer: It was also found that patients with positive ICOSL in the tumors had poorer survival outcomes in TNBC and non-TNBC (P = 0.003, P = 0.012 respectively, Figs. 3B and 3C), as well as in luminal A/B breast cancer (P = 0.001, Fig. 3D), but not in patients with HER2 positive breast cancer (P = 0.826, Fig. 3E).