Moreover, in-depth analysis of breast cancer, especially the basal-like breast cancer for the correlation between the levels of PD-L1 (Fig. 6e) or AHR (Fig. 6f) and the infiltration of Treg cells revealed that high levels of PD-L1 and AHR were associated with increased infiltration of Treg cells in patients. The gene discussed is AHR; the disease is breast cancer.