Comparative study of expression of non-coding circular RNAs circBIRC۶ and circCORO۱C in cord blood CD۳۴+ stem cells and its differentiated cells

Backgrounds: Umbilical cord blood hematopoietic stem cells (UCB HSCs) transplantation hasattracted the attention of many researchers due to the low probability of GVHD and HLAmismatching; however, the use of this resource for adults has been limited due to the inadequatenumber of CD۳۴+ HSC from any individual donor. On the other hand, nowadays, circular RNAs(circRNAs) have been shown to be involved in stem cell properties. In this study, severalcandidate circRNAs, including circCORO۱C and circBIRC۶ were selected from circBase andtheir functional role in CD۳۴+ HSCs was investigated.Materials and Methods: UCB CD۳۴+ HSCs were separated using the MACS system, and itspurity was confirmed by flow cytometry. The StemMACS HSC‐CFU medium was used todifferentiate the cells until the appointed days (۷th and ۱۴th days) and the total RNA wasextracted from them. Then, the expression level of these circRNAs was measured using qRTPCR.The quantitative analysis of GATA-۱ gene and PU۱ gene as well as quantitative analysis ofNANOG and SOX۲ genes were used to conduct molecular evaluation of differentiated cells.Results: The results showed that the expression levels of circBIRC۶ and circCORO۱C as well asthe expression levels of NANOG and SOX۲ were significantly downregulated duringdifferentiation. Furthermore, the expression levels of GATA-۱ and PU-۱ were upregulated on the۷th day compared with the control group and were downregulated on the ۱۴th compared with the۷th day.Conclusion: The present study showed that circBIRC۶ and circCORO۱C were involved in theprocess of self-renewal of CD۳۴+ HSCs, and their expression is downregulated bydifferentiating these cells. Moreover, in future applied studies, the effect of manipulation onthese genes can be investigated in order to achieve maximum proliferation withoutdifferentiation of umbilical cord blood stem cells.

Keywords:

Hematopoietic stem cells , circRNA , circBIRC۶ , circCORO۱C