In a TCGA cohort of breast cancer cases, GM-CSF mRNA expression was seen in 375 (34.8%) of 1075 cases, and GM-CSF-positive cases showed higher gene expression levels of CD8a, Iba1, PD-L1, PD-L2, and lymphocyte activation-related genes such as IFN-γ and Granzyme B as compared to the levels in GM-CSF-negative cases (Supplemental Fig. 1A). The gene discussed is PDCD1LG2; the disease is breast cancer.