“…They have the stem cell characteristics of being able to differentiate into multiple cell lineages such as osteoblasts, chondrocytes, adipocytes and myoblasts and they express a consistent set of marker proteins on their surface (Brooks, Bundred et al 1997;Pittenger, Mackay et al 1999). Mesenchymal stem cells have been used in a number of laboratories in co-culture experiments with breast cancer cell lines or primary tumour cells and have been found to influence breast cancer cell adhesion, morphology, gene expression, proliferative capacity and growth characteristics (Brooks, Bundred et al 1997;Hombauer and Minguell 2000;Fierro, Sierralta et al 2004;Oh, Moharita et al 2004). They have been shown in vivo to be able to migrate to sites of tissue damage and to primary tumour sites, and to modify the ability of breast cancer tumours to metastasize to other organs, making them potentially interesting vehicles for cell-based anti-tumour agents (Ferrari, Cusella-De Angelis et al 1998;Hall, Dembinski et al 2007;Rhodes and Burow 2010).…”