MMP8 and cancer: N1 TANs educate effector T cells to reject tumors, elicit apoptosis of malignant cells by TRAIL, produce and secrete reaction oxygen species (ROS) to lyse cancer cells, participate in ADCC, and release matrix metalloproteinase 8 (MMP-8) to degrade the extracellular matrix (ECM) which is beneficial for tumor metastasis.