Circular RNA hsa_circ_0005046 and hsa_circ_0001791 May Become Diagnostic Biomarkers for Breast Cancer Early Detection.

Breast cancer (BC) is one of the most common lethal diseases in women worldwide. Recent evidence has shown that covalently closed Circular RNA (circRNA) deregulation is observed in different human malignancies and cancers. Lately, circRNAs are being considered as a new diagnostic biomarker; however, the mechanism and the correlation of action between circRNAs and BC are still unclear. In the present study, we try to investigate the expression level of hsa_circ_0005046 and hsa_circ_0001791 in BC. By using quantitative real-time polymerase chain reaction (qRT-PCR), expression profiles of candidate circRNAs were detected in 60 BC tissue and paired adjacent normal tissues. Furthermore, the clinicopathological relation and diagnostic value were estimated. Our results showed the higher expression levels of hsa_circ_0005046 and hsa_circ_0001791 in BC tissues compared to paired adjacent normal tissues with value ( < 0.0001) for both circRNAs, and the area under the receiver operating characteristic (ROC) curve was 0.857 and 1.0, respectively; in addition, a total 10 miRNAs that can be targeted by each candidate circRNAs was predicted base on bioinformatics databases. Taken together, for the first time, the results of our study presented high expression levels of hsa_circ_0005046 and hsa_circ_00017916 in BC; although there was no direct correlation between the high expression level of both circRNAs with clinic pathological factors, except hsa_circ_0001791 association with estrogen receptors (ER), high ROC curve in expressed samples indicated that both circRNAs could be used as a new diagnostic biomarker for BC. Moreover, miRNAs selection tools predicted that miR-215 and mir-383-5p which have a tumor suppressor role in BC can be targeted by our candidate circRNAs to affect the PI3K/AKT pathway; in conclusion, further studies are required to validate the oncogene role of our candidate circRNAs through the PI3k pathway.