Long non-coding RNA00544 serves as a potential novel predictive and prognostic marker for HR+ HER2− subtype breast cancer

Luminal breast cancers (BC) account for majority of breast cancer. Due to its heterogeneity and the development of treatment resistance, luminal BC patients can vary substantially. Long noncoding RNAs (lncRNAs), as we known, is involved in breast cancer progression. Here, we aim to identify the lncRNAs which are involved in the particular type luminal BC progression. By Gene Chips analysis, we found a novel lncRNA00544, which was highly expressed in the metastatic axillary nodes compared with corresponding luminal BC tissues (fold change = 2.26, P = 0.043). This result was confirmed in luminal BC cell lines (p = 0.0113) and 49 paired breast cancer samples compared with in corresponding controls (p = 0.011). Furthermore, Kaplan–Meier survival curves of 373 breast cancer patients indicated that disease-free survival was significantly poor in breast cancer patients with high lncRNA00544 expression (p < 0.001). Univariate and multivariate Cox regression analyses showed that lncRNA00544 was a significant independent prognostic biomarker in luminal BC patients. Further analysis showed that the prognosis of high lncRNA00544 expression in breast cancer patients was actually related to HR + HER2− subtype. Together, our studies indicate that lncRNA00544 may represent a novel predictive and prognostic indicator in luminal BC patients.