The KLF6 Super Enhancer Modulates Cell Proliferation  via MiR-1301 in Human Hepatoma Cells

KumChol       Ri; Chol       Kim; CholJin       Pak; PhyongChol       Ri; HyonChol       Om

Abstract

Background: Recent studies have attempted to elucidate the function of super enhancers by means of microRNAs. Although the functional outcomes of miR-1301 have become clearer, the pathways that regulate the expressions of miR-1301 remain unclear.

Objective: The objective of this paper was to consider the pathway regulating expression of miR- 1301 and miR-1301 signaling pathways with the inhibition of cell proliferation.

Methods: In this study, we prepared the cell clones that the KLF6 super enhancer was deleted by means of the CRISPR/Cas9 system-mediated genetic engineering. Changes in miR-1301 expression after the deletion of the KLF6 super enhancer were evaluated by RT-PCR analysis, and the signal pathway of miR-1301 with inhibition of the cell proliferation was examined using RNA interference technology.

Results: The results showed that miR-1301 expression was significantly increased after the deletion of the KLF6 super enhancer. Over-expression of miR-1301 induced by deletion of the KLF6 super enhancer also regulated the expression of p21 and p53 in human hepatoma cells. functional modeling of findings using siRNA specific to miR-1301 showed that expression level changes had direct biological effects on cellular proliferation in Human hepatoma cells. Furthermore, cellular proliferation assay was shown to be directly associated with miR-1301 levels.

Conclusion: As a result, it was demonstrated that the over-expression of miR-1301 induced by the disruption of the KLF6 super enhancer leads to a significant inhibition of proliferation in HepG2 cells. Moreover, it was demonstrated that the KLF6 super enhancer regulates the cell-proliferative effects which are mediated, at least in part, by the induction of p21and p53 in a p53-dependent manner. Our results provide the functional significance of miR-1301 in understanding the transcriptional regulation mechanism of the KLF6 super enhancer.

Keywords: CRISPR, genome editing, KLF6 gene, miR-1301, Super Enhancer (SE), hepatoma cells.

Graphical Abstract

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