H19 and breast cancer: Furthermore, a large number of lncRNAs have been identified as oncogenes, such as HOTAIR and H19, which were significantly positive with poor prognosis in breast cancer,6 and the prognostic signatures of lncRNAs have been reported in various cancers, such as seven‐lncRNA signatures in non‐small‐cell lung cancer7 and six‐lncRNA signatures in glioblastoma multiform.8