The correlation plots from two cancer types with the highest Rho values (Spearman’s rank-order correlation coefficient) are shown in Fig. 7E. While there is either no significant or a less significant association between gene expression and neutrophil purity, there is consistently a highly significant association between MMP8 or 9 expression and the level of neutrophil infiltration, indicating a conserved role for MMP8 or 9 in neutrophil mobilization and recruitment in multiple cancers. Here, MMP8 is linked to cancer.