Study of Hypericin effect on microRNAs Expression Level in MCF-۷ Breast Cancer Cells Using microRNA Sequencing

Background and Aim: MicroRNAs are short noncoding RNAs which function as post-transcriptional regulators in gene expression. Breast cancer is one of the most prevalent causes of cancer-related deaths among women. Studies have shown that hypericin, one of the main components of Hypericum Perforatum, has apoptotic and cytotoxic effects on tumor cell lines in low concentrations and prevents tumor-induced angiogenesis. Therefore, we used it on MCF-۷ cell line, a human breast adenocarcinoma cell line, to investigate its cytotoxic effects on microRNAs.Methods: The MCF-۷ cell line was treated with various concentrations of hypericin for ۲۴ and ۴۸ h. Cytotoxicity activity was confirmed by MTT assay and cell viability was measured by ELISA Reader in ۵۷۰ nm. In addition, apoptosis was determined by Annexin V/Propidium Iodide Assay. Total RNA isolation was also done using TRIZOL and then sent for Next Generation sequencing of microRNAs and the data were analyzed using multiple software and pathways.Results: DE (Differential Gene Expression) analysis showed significant differential expression in more than ۱۰۰ microRNAs between the treated and control samples including miR-۱۲۵b-۵p with target genes such as CCNJ, MEGF۹ and ENPEP. Moreover, miR-۱۹۴-۵p was revealed as one of the down-regulated miRNAs under the effect of hypericin. In addition, QKI was shown as the most targeted gene by up-regulated miRNAs, while ZNF۱۴۸ was the most targeted gene by down-regulated miRNAs in this study. GO and KEGG pathway enrichment were also done.Conclusion: The differentially expressed miRNAs under the treatment of hypericin, had effects on biological pathways such as PI۳k/Akt, MAPK and Wnt signaling pathway.