ERBB2 and breast cancer: Just recently, Fernandez-Nogueira et al. found the H1 receptor to be overexpressed in basal and HER2-targeted therapy-resistant breast cancer cells, and demonstrated that inhibition of the H1 by terfenadine led to increased cell death and a reduction in cell proliferation, although only in these two specific types of breast cancer.9 H1 antihistamines have also been shown to exert growth-inhibitory effects and promote apoptosis in vitro in other cancer cell lines.10,30–32