These analyses indicated that MMP9 expression was significantly correlated infiltrating levels of all six immune cell types and tumor purity, especially high for dendritic cell, B cell, macrophage and CD8+ T cells; SPP1 expression was significantly associated with infiltrating levels of macrophage and dendritic cell; and SRC expression was significantly linked to macrophage, dendritic cell, CD4+ T cells, B cell and neutrophil (S2 Fig). The gene discussed is MMP9; the disease is neoplasm.