MMP8 and neoplasm: Tumour-infiltrating neutrophils show plasticity, and based on murine models, separate anti-tumour N1 and pro-tumour N2 neutrophil subsets have been suggested.43 However, the definitions and reliable markers for different neutrophil subsets in human patients still require further research,44 and subsequent studies concentrating on diverse tumour-infiltrating neutrophil subsets could enlighten the potential role of MMP-8 in these cells.