BMP2 promotes migration and invasion of breast cancer cells via cytoskeletal reorganization and adhesion decrease: an AFM investigation

Bone morphogenetic protein 2 (BMP2) has been shown to modulate the proliferation and differentiation of breast cancer cells. However, the biochemical effects and mechanisms remain unknown. In this paper, the effects of recombinant human BMP2 on the migration of MCF-7 cells-one breast cancer cell line, using transwell and wound healing experiments, as well as on the cellular morphology, cytoskeleton, cell surface adhesion, and stiffness detected at subcellular level by an atomic force microscope, were investigated. After BMP2 treatment, the untreated round-shaped MCF-7 cells transformed to a spindle-like shape with lots of specialized structures, such as lamellipodia, filopodia, membrane protrusions, and others, which are essential for cellular migration or spreading. Moreover, flow cytometry quantitatively detected the BMP2-induced changes in the expression of adhesion molecules, a significant rise of CD44, and a remarkable drop of E-cadherin. The data indicated that BMP2 promoted the migration and invasion of MCF-7 cells by regulating the reorganization of cytoskeleton and the expression of adhesion molecules in/on the cells. Thus, it is very imperative to evaluate the oncogenicity of BMP2 when used in tissue engineering.