Few articles from mid-size datasets described the potential role of SQLE overexpression in the definition of a prognostically unfavorable stage I-II estrogen receptor positive (ER+) breast cancer subgroup33 or in Afro-American luminal-A breast cancer patients34, and the identification of clusters of breast tumors characterized, among other alterations, by SQLE CN amplification and overexpression25, or by its aberrant methylation and expression patterns in concomitance with MYC amplification35. Here, ESR1 is linked to breast cancer.