Metastatic brain tumors — often from lung, breast, or skin cancers — are the most commonly observed tumors within the brain and account for about 30 percent of advanced breast cancer metastases,” said Khalid Shah, an HSCI principal faculty member and director of the Molecular Neurotherapy and Imaging Laboratory in the MGH Departments of Radiology and Neurology, who led the study. “Our results are the first to provide insight into ways of targeting brain metastases with stem cell-directed molecules that specifically induce the death of tumor cells, and then eliminating the therapeutic stem cells.
In their search for novel, tumor-specific therapies that could target multiple brain metastases without damaging adjacent tissues, the research team first developed a mouse model that more closely mimicked what is seen in patients. They found that injecting into the carotid artery breast cancer cells that express markers that allow them to enter the brain (cells labeled with bioluminescent and fluorescent markers to enable tracking by imaging technologies) resulted in the formation of many metastatic tumors throughout the brain, mimicking what is seen in advanced breast cancer patients. Current therapeutic options for such patients are limited, particularly when there are many metastases.