Bone morphogenetic protein 2 (BMP-2) induces in vitro invasion and in vivo hormone independent growth of breast carcinoma cells.

Breast cancer cell lines migrated towards a BMP-2 source depending on BMP-2 concentration. After a short exposure to BMP-2, the cells were able to migrate through matrigel. MCF-7 cells transfected with the BMP-2 gene also showed enhanced migratory properties and high expression of the metastasis-related gene BCSG1. In a xenograft model without estrogen supplementation MCF-7/BMP-2 cells formed tumors. These tumors were characterised by an enhanced vasculature and the formation of chondroid and osseous structures. In conclusion elevated levels of BMP-2 enhance the tumorigenic properties of breast carcinoma cells and drive the cells towards a more aggressive phenotype with estrogen independent growth.