Spontaneous Fusion of MSC with Breast Cancer Cells Can Generate Tumor Dormancy

Direct cellular interactions of MDA-MB-231cherry breast cancer cells with GFP-transduced human mesenchymal stroma/stem-like (MSCGFP) in a co-culture model resulted spontaneous cell fusion by the generation MDA-MSC-hyb5cherry GFP hybrid cells. The proliferative capacity MDA-MSC-hyb5 was enhanced about 1.8-fold when compared to parental In contrast induced tumor development vivo within 18.8 days, initially remained quiescent dormancy-like state. At distinct time points after injection, NODscid mice started develop cell-induced tumors up half year later. Following initiation, however, growth and formation metastases various different organs occurred rapidly 10.5 days. Changes gene expression levels were evaluated RNA-microarray analysis revealed certain increase dormancy-associated transcripts MDA-MSC-hyb5. Chemotherapeutic responsiveness partially MDA-MB-231 However, some resistance, e.g., for taxol detectable Moreover, drug response changed during cells; this suggests presence unstable phenotypes MDA-hyb5 increased heterogeneity.