ESR1 and gastric cancer: Further studies showed that estrogen played an important role in gastric cancer cells proliferation and invasion (Tang et al., 2017; Ge et al., 2018; Yongle Zhang et al., 2020), which could be mediated via the Src signal pathway by estrogen receptors, for example, ER-α36 (Wang et al., 2013; Wang et al., 2020).