S100A9 and breast cancer: Analysis of the cohort of patients with breast cancer brain metastases59,60 who were treated with radiotherapy confirmed the correlation between S100A9 expression levels and survival from brain metastasis diagnosis (Fig. 5e and Supplementary Table 16), which was reproduced by S100A8 (Supplementary Fig. 5c,d and Supplementary Table 16), as in experimental models (Supplementary Fig 4e,f).