TGFB1 and neoplasm: Another example is transforming growth factor (TGF)‐β1, a crucial member of the TGF family, which induces epithelial‐mesenchymal transition (EMT) in tumor progression and metastasis.[106] A tumoral ECM‐mimicking matrix was made using LbL films with controllable stiffness, with dopamine used to immobilize TGF‐β1 with a high efficiency of ≈90%.[107] The stiff matrix with immobilized TGF‐β1 (i‐TGF) was the only condition able to induce mesenchymal phenotype and promote the EMT progression of hepatocellular carcinoma cells.