SDC1 and neoplasm: Conversely, Mn2+ acts as an integrin activator in the TME: accumulation in primary Lewis lung cancer alters tumor cell surface molecules (e.g., syndecan-1, β1-integrin) to enhance migration and invasion, while tumor-secreted Mn-containing extracellular vesicles facilitate Mn accumulation in perivascular regions and metastatic sites 107.