A recent study revealed that overexpression of SLC7A5 protein was significantly associated with histopathological grade in ER+ BC patients, and that SLC7A5 mRNA expression was positively correlated with the expression of marker of proliferation Ki-67 and hypoxia inducible factor 1 subunit alpha in ER+ BC patients [43]. The gene discussed is SLC7A5; the disease is breast cancer.