Imaging transforming growth factor-Β signaling dynamics and therapeutic response in breast cancer bone metastasis

Although the TGF-β signaling pathway has been implicated in breast cancer metastasis, studies are hampered by a lack of animal models for in vivo analysis of metastasis signaling pathways. Here a noninvasive xenograft model is described that uses a dual bioluminescence reporter system to study TGF-β signaling in bone metastasis. Disruption of TGF-β signaling in early—not late—stage metastasis is shown to markedly reduce bone metastasis burden.