miR-203 inhibits the expression of collagen-related genes and the proliferation of hepatic stellate cells through a SMAD3-dependent mechanism

Abstract

Abstract. Activation of hepatic stellate cells (HSCs) is a pivotal event during hepatic fibrogenesis. Activated HSCs are the main source of collagen and other extracellular matrix (ECM) components, and emerging antifibrotic therapies are aimed at preventing ECM synthesis and deposition. MicroRNAs (miRNAs) have been demonstrated to exert regulatory effects on HSC activation and ECM synthesis. In the present study, the HSC-T6 rat hepatic stellate cell line was transiently transfected with a miRNA (miR)-203 mimic, which is an artificial miRNA that enhances the function of miR-203, with a miR-203 inhibitor or with a scramble miRNA negative control. mRNA and protein expression levels of collagen (COL) 1A1, COL3A1, α-smooth muscle actin (α-SMA) and mothers against decapentaplegic homolog 3 (SMAD3) were assessed using reverse transcription-quantitative polymerase chain reaction and western blot analysis, respectively. The interaction between miR-203 and the 3'-untranslated region (UTR) of SMAD3 mRNA was examined using a dual-luciferase reporter assay. The proliferative capabilities of activated HSCs were measured using an MTT assay. The present results demonstrated that the mRNA and protein expression levels of COL1A1, COL3A1, α-SMA and SMAD3 were significantly upregulated following transfection of HSC-T6 cells with the miR-203 inhibitor. Conversely, COL1A1, COL3A1, α-SMA, and SMAD3 mRNA and protein expression appeared to be downregulated in rat HSCs transfected with miR-203 mimics. Notably, the inhibition of miR-203 expression was revealed to promote HSC proliferation, whereas increased miR-203 expression suppressed the proliferative capabilities of HSC-T6 cells. Furthermore, SMAD3 was revealed to be a direct target of miR-203. The present study suggested that miR-203 may function to prevent the synthesis and deposition of ECM components, including COL1A1, COL3A1 and α-SMA, and to inhibit the proliferation of HSCs through a SMAD3-dependent mechanism. Therefore, it may be hypothesized that miR-203 has potential as a novel target for the development of alternative therapeutic strategies for the treatment of patients with hepatic fibrosis in clinical practice.

Molecular Pathogenesis of Chlamydia Disease Complications: Epithelial-Mesenchymal Transition and Fibrosis

“…The TGF-␤ maturation processing protease, furin, is the direct target of miR-24 (30)(31)(32). miR-203 controls fibrosis and maintains epithelial integrity by specifically targeting SMAD3, a key intracellular mediator of TGF-␤ signaling, leading to EMT and production of ECM proteins during fibrosis (6,33). In addition, miR-203 targets the EMT-and cell invasion-promoting transcription factor Snail2 (Slug) (34) and SMAD3 (33,34) to prevent fibrosis.…”

“…miR-203 controls fibrosis and maintains epithelial integrity by specifically targeting SMAD3, a key intracellular mediator of TGF-␤ signaling, leading to EMT and production of ECM proteins during fibrosis (6,33). In addition, miR-203 targets the EMT-and cell invasion-promoting transcription factor Snail2 (Slug) (34) and SMAD3 (33,34) to prevent fibrosis. Furthermore, among the key downregulated miRNAs, miR-185 targets TGF-␤ and collagen type I to control tissue fibrosis (6,35) and miR-221 targets fibrosis-promoting osteopontin, which is also the target of the polyphenol epigallocatechin-3-gallate (EGCG), which is found in green tea and upregulates miR-221 (36).…”

miR‑939‑3p promotes epithelial‑mesenchymal transition and may be used as a prognostic marker in hepatocellular carcinoma

“…HCC is one of the most common tumor types worldwide, with high morbidity and mortality rates (1). Although numerous oncogenes and tumor suppressors have been reported in HCC (21)(22)(23)(24), the underlying mechanisms of development and recurrence of HCC remain unclear. Over the past decade, the overall survival rate of HCC has remained unsatisfactory and is only 22-35%.…”

MicroRNA‑203a‑3p is a candidate tumor suppressor that targets thrombospondin 2 in colorectal carcinoma

“…Accumulating evidence has revealed associations between miRNAs and a wide range of tumors (31,32) and, more specifically, between aberrant miRNA-203a-3p expression and tumorigenesis (13)(14)(15). miRNA-203a-3p serves different roles in a variety of cancers, depending on the type of the tumor and the targeted genes.…”

“…The occurrence and progression of several tumor types have been found to be associated with abnormal miRNA expression (7)(8)(9)(10)(11). Reportedly, aberrant miRNA-203a-3p expression has been detected in numerous cancers (12)(13)(14)(15)(16)(17)(18); however, its role and mechanism of action in CRC remain elusive. Therefore, the present study was conducted to investigate miRNA-203a-3p expression in CRC, and elucidate the mechanism underlying the inhibition of apoptosis and promotion of metastasis in CRC.…”