Recent studies have shown that long non-coding RNAs (lncRNAs) have key functions during breast cancer development. Considering the complexity of IncRNAs regulatory network, the identification of novel and functional lncRNAs associated with breast cancer is thus very important. By using Agilent LncRNA Human Gene Expression Microarray, we identified a number of lncRNAs that were differentially expressed in breast cancer compared to their corresponding adjacent tissues. According to the microarray, the expression of p10247, henceforth named as lncRNA-BCHE (standing for lncRNA high expressed in breast cancer), was found to be uniformly higher in all the five breast cancer tissues tested, and this was further confirmed in 56 breast cancer tissues by real-time RT-PCR. The function of lncRNA-BCHE in breast cancer cells was tested by knockdown and over-expression experiments in vitro. We also analyzed the public cohorts of breast cancer patients on the Kaplan Meier plotter platform. Clinical analysis revealed that the expression of lncRNA-BCHE was significantly correlated with advanced clinical stage and lymph node metastasis. Our data indicate that lncRNA-BCHE regulates the growth, migration and invasion of breast cancer cells. In addition, we found that these functions are mediated, at least in part, by the regulation of integrin subunit beta 1 (ITGB1) levels. The expression of ITGB1 serves as a negative prognostic factor and metastasis risk predictor in breast cancer, irrespective of subtype and therapeutic regimen. In summary, our results suggest that lncRNA-BCHE is an oncogenic lncRNA enhancing the growth and metastatic potential of breast cancer cells, and a potential predictor of breast cancer metastatic progression.
Keywords: Breast cancer; Integrin subunit beta 1; LncRNA-BCHE; Metastasis.