Enhancing HOTAIR/MiR-10b Drives Normal Liver Stem Cells Toward a Tendency to Malignant Transformation Through Inducing Epithelial- to-Mesenchymal Transition.

Abstract

Previously, other groups and our team consistently have demonstrated that the possible origination of liver cancer stem cells (LCSCs) is the malignant transformation from liver normal stem cells (LNSCs). However, this complex and multi-step process is far from clear due to the accumulation of various gene dysregulations. Because non-coding RNAs (ncRNAs) could regulate multiple genes, a family of genes, and even whole chromosomes, this study further investigated the effect of dysregulated short ncRNA microRNA-10b and long ncRNA HOX transcript antisense RNA (HOTAIR) between LNSCs and LCSCs on phenotype reversion. To clarify the role of ncRNA in malignant transformation of LNSCs, we used lentivirus transduction to enhance the miR-10b and HOTAIR expression levels in our previously isolated rat LNSCs. The malignant abilities of proliferation, invasiveness, and tumorigenesis were observed and compared in cells before and after ncRNAs enhancement. After microRNA-10b and HOTAIR were enhanced separately, several cancer stem cell (CSC)-like traits appeared in these LNSCs, including in vitro-enhanced proliferative capacity, expression of putative LCSC markers, progressive invasive ability, and even in vivo aggravation into and taking the place of normal liver tissue. Furthermore, strengthened expression of these ncRNAs partially degraded E-cadherin in LNSCs, which is one of the classic markers in epithelial-to-mesenchymal transition (EMT). HOTAIR or miR-10b enhanced in LNSCs may drive the LNSCs to a tendency toward malignant transformation. This study partially uncovers the mechanism by which miR-10b or HOTAIR promotes malignant transformation of LNSCs through down-regulating E-cadherin and inducing EMT.