TACR1 and breast cancer: Interestingly, the tachykinin receptor TACR1/NK-1R is overexpressed in some gliomas66,67 and contributes to glioma pathobiology, and there is evidence that this pathway is also involved in brain metastasis in breast cancer,68 suggesting that treatments modulating tachykinin function could be harnessed for a dual purpose, further increasing the benefits to patients with limited treatment options.