GABAergic signaling facilitates breast cancer metastasis by promoting ERK1/2-dependent phosphorylation

(GAD65/67) and GABAB receptor are expressed in 4T1 mouse breast cancer cells, MCF-7 human breast cancer cells and human breast cancer tissue. Baclofen, a GABABR agonist, significantly promoted 4T1 cells invasion and migration in vitro and metastasis in vivo, an event that was attenuated by GABABR antagonist CGP55845. Baclofen-induced breast cancer metastasis was mediated by ERK1/2 pathway.