From the same study, the tissue microarray expression data of tamoxifen resistant breast tumors demonstrated that FGFR3 expression was significantly increased compared with the normal cells, resulting in activation of the mitogen-activated protein kinase (MAPK) and phosphoinositide 3-kinase (PI3K) signalling pathways, both of which have been implicated in tamoxifen resistance in breast cancer [70]. This evidence concerns the gene WNK2 and breast cancer.