Experimental and Bioinformatic Clues to the Potential Roles of hsa_circ_0013958 and hsa_circ_0003028 in Clinopathophysiology of Breast Cancer

Circular RNAs (circRNAs), covalently closed single-stranded non-coding RNAs (ncRNAs), play pivotal roles in development and progression of breast cancer (BC). Although the roles of hsa_circ_0013958 and hsa_circ_0003028 in some malignancies have been explored, their function and expression in breast tumors are still unknown. This study was aimed to bio-informatically and experimentally evaluates the expression and potential function of hsa_ circ_0013958 and hsa_circ_0003028 in BC. Materials and Methods: The quantitative re-al-time PCR method was used to determine the expression of hsa_circ_0013958 and hsa_ circ_0003028 in 50 tumor samples and matched adjacent non-cancerous tissues. Besides, we used bioinformatic approaches to identify potentially important competing endogenous RNA (ceRNA) networks that are regulated by these circRNAs using some databases and software tools. Results: The hsa_circ_0013958 was significantly down-regulated in breast tumors com-pared with adjacent normal tissues, while the hsa_circ_0003028 had an upregulated pattern. Interestingly, it is found the higher expression of hsa_circ_0013958 showed association with a lack of use of hair dye as well as age at menarche ≥14 years in subjects. On the other hand, hsa_circ_0003028 expression was meaningfully related to age at first full-term pregnancy, an-tiperspirants use, and regular menstruation. Next, we found that these two circRNAs can poten-tially regulate some circRNAs-mediated miRNA sponge regulatory networks. Conclusion: The current work indicated that the hsa_circ_0013958 and hsa_circ_0003028 had reverse expres-sion patterns in breast tumors, and it seems that they play key roles in the physiopathology of this cancer through potential key regulatory ceRNA functions. However, further functional studies are needed to validate these bioinformatically observed roles.