Human mesenchymal stem cell multipotency on PCL films with different stiffnesses. hMSCs were cultured on PCL films and switched to specific differentiation media for 14 days. The formation of lipid vacuoles (FABP4 staining, red), calcium deposits (ALIZARIN RED S staining, red) is shown in cells cultured in adipogenic (ADIPO) or osteogenic media (OSTEO). The occurrence of chondrogenic (CHONDRO) differentiation after 14 days in differentiation medium was confirmed by Masson's trichrome staining. (a) hMSCs grown for 1 week on the softest (0.9 MPa, left) or the stiffest (133 MPa, right) substrates were detached and seeded onto growth-factor-reduced MATRIGEL™ for 3 h. (b) Formation of tubular structures (Scale bars: 25 μm). (c) Number of tubules and the average tubule length measured by ImageJ software.