Propranolol: What is BLOCKing Its Clinical Investigation in Breast Cancer?

Presurgical propranolol modulates biomarkers associated with breast cancer progression. β-adrenergic signaling promotes invasion, epithelial-to-mesenchymal transition phenotype, and immune cell infiltration into the tumor microenvironment. Blockade of the β-adrenergic receptor signaling with propranolol, along with potential future combinatorial strategies, holds promise for reducing breast cancer progression and metastasis.See related article by Hiller et al., p. 1803.