MATN4 (matrilin 4) is a major extracellular matrix component of cartilage involved in matrix organization and protein binding 1. Beyond its structural role, MATN4 functions as a hypoxia-responsive gene regulated by HIF-1α, promoting osteosarcoma cell proliferation, migration, and invasion under hypoxic conditions 2. MATN4 expression is selectively enriched in odontoblasts compared to pulp tissue, suggesting utility as an odontoblast differentiation marker 3. In wound healing contexts, MATN4 expression is induced by valproic acid treatment and associates with modulation of collagen fiber architecture in postoperative conjunctival tissue 4. Disease relevance includes associations with diabetic neuropathy in T2DM patients 5, downregulation during osteoarthritis progression 1, and identification as a novel candidate gene in neurogenetic disorders 6. Additionally, MATN4 showed differential expression between Chinese and Western breast cancer patients and correlated with specific imaging phenotypes 7. Environmental exposure to particulate matter (PM10) associates with altered MATN4 methylation patterns 8. These findings establish MATN4 as a multifunctional matrix protein with roles in development, pathological fibrosis, malignancy, and metabolic disease complications.