For example, there were more samples diffusely expressing OTR (diffusely expressing was defined as that >80% cells were stained by IHC detection) in ER+ samples (18 out of 32 ER+ patients) than in ER-negative (ER−) patients (7 out of 19 ER− patients) [88], with OTR gene expression being 8.6-fold higher in breast tumour tissues of ER+ patients (n = 27) than ER− patients (n = 10) [58]. This evidence concerns the gene OXTR and breast neoplasm.