THE EFFECT OF THYMOQUINONE ON THE miRNA PROFILE OF MCF-7 BREAST CANCER CELLS

Background and aim: Thymoquinone (TQ), which is the most bioactive component of Nigella sativa (Black cumin), exhibits anticancer characteristics based on cell culture and experimental animal studies. However, molecular action mechanisms of these effects are not clear. MicroRNAs (miRNAs), small non-coding RNAs of approximately 22 nucleotides,  are an emerging class of gene expression modulators with relevant roles in several biological processes, including cell differentiation, development, apoptosis, and regulation of the cell cycle. The purpose of this study was to investigate the potential impact of thymoquinone (TQ) on MCF-7 human breast cancer cell miRNAs.  Materials and methods: The expression levels of miRNAs in MCF-7 cell and TQ treated MCF-7 cells were estimated by miRNA sequencing. The expressions of miRNAs were determined real-time qPCR. Results: We detected 10 down-regulated mirRNAs (hsa-miR-1, let 7c-5p, hsa-miR-15b-5p, hsa-mir-202-3p, hsa-miR-214-3p, hsa-miR-210-3p, hsa-miR-31-5p, hsa-miR-424-5p, hsa-miR-497-5p, hsa-miR-98-5p) and 2 up regulated  miRNAs (hsa-miR-22-3p, hsa-miR-132-3p) in TQ treated groups, comparing with control group. These findings highlight the effects of TQ miRNA profile and molecular mechanism on MCF-7 cells. Conclusion: Finally, according to computational analyses using validated databases PI3 kinase/AKT (hsa04151), Wnt (hsa04310), MAPK (hsa04010) and p53 (hsa 04115) signaling pathways seem to be the key targets of these TQ groups of miRNA.