Background
Circular RNAs (circRNAs), one of the recent subclasses of non-coding RNAs (ncRNAs), show pivotal functions in regulation of gene expression and have significant roles in malignancies including breast cancer (BC). This study was aimed to assess the hsa_circ_0001445 and hsa_circ_0020397 expression and role in BC, as well as the potential circRNA/miRNA/mRNA crosstalk in these contexts.
Conclusion
It is suggested that hsa_circ_0001445 and hsa_circ_0020397 with two opposite roles may be involved in BC development through sponging some miRNAs regulating ceRNA networks. However, their molecular interactions should be validated by further functional studies.
Methods
The expression of hsa_circ_0001445 and hsa_circ_0020397 in 50 breast tumors and 50 normal tissues adjacent to the tumors was investigated using quantitative real-time polymerase chain reaction (qRT-PCR). Finally, bioinformatics analyses were used to uncover hsa_circ_0001445, hsa_circ_0020397-miRNA-mRNA potential regulatory networks.
Results
The hsa_circ_0001445 expression was considerably downregulated in malignant tissues compared to their normal counterparts (P=0.020), while the hsa_circ_0020397 showed an upregulated pattern (P<0.001). Additionally, it was observed that the higher expression of hsa_circ_0001445 was associated with hair dye avoidance (P=0.034) and normal body mass index (BMI) (P=0.016) while hsa_circ_0020397 over-expression had an important association with a lack of vitamin D consumption (P=0.039). On the other hand, lower expression of hsa_circ_0001445 was significantly associated with age at menarche ˂14 years (P=0.027). Our study also revealed that the two circRNAs have potential ability to regulate key mRNAs and miRNAs in competing endogenous RNA (ceRNA) networks.