Objective To preliminarily explore the role of microRNA-10a-5p (miR-10a-5p) in the anti-ovarian cancer effect of shikonin.
Methods The expression level of miR-10a-5p in tumors was analyzed based on database; the expression of miR-10a-5p was detected by reverse transcription quantitative real-time polymerase chain reaction (RT-qPCR) after transient transfection of miR-10a-5p mimic and NC; the CCK-8 assay was used to detect half inhibitory concentration (IC50) of shikonin in SKOV3 cells; the cell apoptosis and cell cycle were detected by flow cytometry; the cell death of each group was compared with the staining of live and dead cells.
Results The miR-10a-5p was abnormally expressed in a variety of tumors. Compared with the control group, the expression level of the miR-10a-5p in SKOV3 cells could be significantly up-regulated by about 80 times after transfecting miR-10a-5p mimic (P < 0.000 1); miR-10a-5p can promote the apoptosis of ovarian cancer cells and improve the sensitivity of SKOV3 cells to shikonin. The IC50 of mir-10A-5P decreased by 42.9% from 2.45 μmol/L to 1.40 μmol/L. Compared with NC group, transfection mimic could significantly promote the apoptosis of SKOV3 cells (6.73% versus 17.71%, P=0.007 5). Compared with the non-shikonin group, shikonin significantly promoted the apoptosis of ovarian cancer cells (6.73% versus 82.48%, P < 0.000 1); in addition, miR-10a-5p could significantly promote the apoptosis of SKOV3 with shikoin (82.48% versus 96.80%, P < 0.000 1). The staining results of live and dead cells showed that miR-10a-5p combined with shiverin caused significant death of more cells (P < 0.000 1); the miR-10a-5p combined with shiverin significantly increased the proportion of S-phase cells (P < 0.000 1), thus inhibiting cell proliferation. GATA6 was predicted to be a target of miRNA-10a-5p by Targetscan7.2. Kaplan-Meier Plotter database analysis suggested that high expression of GATA6 was associated with poor prognosis of ovarian cancer, and the mRNA and protein expression levels of GATA6 were significantly down-regulated after transient transfection with mimic (P < 0.000 1).
Conclusion Both miR-10a-5p and shikonin can promote the apoptosis of SKOV3 cell, and have the synergistic anti-ovarian cancer effect. And miR-10a-5p can significantly improve the drug sensitivity of SKOV3 cell to shikonin, which may be through targeting GATA6 to produce cancer inhibitory effect.