Cooperation of neurotrophin receptor TrkB and Her2 in breast cancer cells facilitates brain metastases.

Background: Patients with primary breast cancer that is positive for human epidermal growth factor receptor 2 (Her2+) have a high risk of developing metastases in the brain. Despite gains with systemic control of Her2+ disease using molecular therapies, brain metastases remain recalcitrant to therapeutic discovery. The clinical predilection of Her2+ breast cancer cells to colonize the brain likely relies on paracrine mechanisms.

Astrocyte-induced Reelin expression drives proliferation of Her2 breast cancer metastases.

Breast cancer metastasis to the brain develops after a clinical latency of years to even decades, suggesting that colonization of the brain is the most challenging step of the metastatic cascade. However, the underlying mechanisms used by breast cancer cells to successfully colonize the brain's microenvironment remain elusive. Reelin is an archetypal extracellular glycoprotein that regulates migration, proliferation, and lamination of neurons.

Inhibition of β2-adrenergic receptor reduces triple-negative breast cancer brain metastases: The potential benefit of perioperative β-blockade.

In response to recent studies, we investigated an association between perioperative β-blockade and breast cancer metastases. First, a retrospective study examining perioperative β-blocker use and cancer recurrence and metastases was conducted on 1,029 patients who underwent breast cancer surgery at the City of Hope Cancer Center between 2000 and 2010. We followed the clinical study and examined proliferation, migration, and invasion in vitro of primary and brain-metastatic breast cancer cells in response to β2-activation and inhibition.

Human breast cancer metastases to the brain display GABAergic properties in the neural niche.

Dispersion of tumors throughout the body is a neoplastic process responsible for the vast majority of deaths from cancer. Despite disseminating to distant organs as malignant scouts, most tumor cells fail to remain viable after their arrival. The physiologic microenvironment of the brain must become a tumor-favorable microenvironment for successful metastatic colonization by circulating breast cancer cells.

Co-evolution of breast-to-brain metastasis and neural progenitor cells.

Brain colonization by metastatic tumor cells offers a unique opportunity to investigate microenvironmental influences on the neoplastic process. The bi-directional interplay of breast cancer cells (mesodermal origin) and brain cells (neuroectodermal origin) is poorly understood and rarely investigated. In our patients undergoing neurosurgical resection of breast-to-brain metastases, specimens from the tumor/brain interface exhibited increased active gliosis as previously described.