BGLAP and cancer: Figure 2D also shows confocal fluorescence micrographs of MDABM after three days of cell growth, stained with AlexaFluor 488 Ab-osteocalcin and Hoechst. The up-regulation of osteocalcin suggested the stiffness-dependent production of calcifications and physically induced trans-differentiation of the cancer cells into osteoblast-like cells, in agreement with our previously results [9]. The same treatment was performed on head–neck cancer cells of the CAL-27 cancer cell line. By contrast, no ARS-positive deposits or increase in osteocalcin expression (Figure 3A) was observed.