MMP28 (matrix metallopeptidase 28) is a member of the matrix metalloproteinase family that plays diverse roles in tissue homeostasis, immune regulation, and disease pathogenesis. The enzyme demonstrates proteolytic activity against casein and contributes to extracellular matrix remodeling [UniProt]. In tissue repair, MMP28 expression is downregulated during wound reepithelialization, suggesting its association with epidermal maturation rather than active healing processes 1. Mechanistically, MMP28 functions as a key regulator of macrophage polarization, promoting M1 to M2 phenotype switching in pulmonary fibrosis 2 and recruiting M2-type tumor-associated macrophages through MAPK/JNK signaling pathway-dependent cytokine secretion in pancreatic cancer 3. In cancer contexts, MMP28 is upregulated in hepatocellular carcinoma where it promotes metastasis via Notch3 signaling and epithelial-mesenchymal transition, serving as an independent prognostic factor 4. The enzyme also contributes to emphysema development by influencing macrophage proteolytic and inflammatory activities 5. Notably, MMP28 expression appears unresponsive to inflammatory stimuli, suggesting distinct regulatory mechanisms compared to other MMPs 6. These findings highlight MMP28 as a therapeutic target for fibrotic diseases and cancer.