miR-32-5p suppresses the progression of hepatocellular carcinoma by regulating the GSK3β/NF-κB signaling

Abstract

Hepatocellular carcinoma (HCC) is a highly fatal form of malignancy that seriously threatens patient survival. The global 5-year survival rate for HCC patients ranges from 15% to 19%, and nearly 80% of patients are diagnosed at an advanced stage. Therefore, exploring the mechanism of HCC development and identifying biomarkers and therapeutic targets for HCC are vital. MicroRNAs (miRNAs), a class of noncoding single-stranded RNAs, are 20–24 nucleotides (nt) long. They play pivotal roles in modulating the progression of diverse diseases. The specific role of miR-32-5p in the development of HCC remains unclear. In this study, qRT-PCR is utilized to precisely determine the downregulated expression levels of miR-32-5p in HCC. Subsequently, functional analysis reveals the suppressive role of miR-32-5p in modulating the proliferative and migratory capabilities of HCC cells. Glycogen synthase kinase 3β (GSK3β) has emerged as a potential target of miR-32-5p, which is confirmed through a dual-luciferase reporter assay. Notably, the expression of GSK3β in HCC tissue specimens is negatively correlated with the abundance of miR-32-5p, and patients with high GSK3β expression have shorter survival time. Furthermore, the targeted downregulation of GSK3β remarkably impedes the proliferation and migration of tumor cells. This study suggests that miR-32-5p inhibits the proliferation and migration of HCC through regulating the GSK3β/NF-κB signaling pathway. Therefore, this study reveals that miR-32-5p exerts its suppressive effect on HCC progression, suggesting that it is a promising target for both diagnostic and targeted therapeutic interventions against HCC.

1. Introduction

Hepatocellular carcinoma (HCC), the predominant type of liver cancer, is globally the fifth most commonly diagnosed malignancy and the fourth leading cause of cancer-associated mortality [1]. In the United States, the mortality rate of liver cancer ranks fifth for male patients and seventh for female patients [2]. In China, HCC is the second most common malignant tumor, indicating its substantial burden on public health [3]. These conditions highlight the ongoing challenges in the prevention and control of HCC.

MicroRNAs (miRNAs), a class of noncoding RNAs with lengths of 20–24 nucleotides (nts), are widely expressed in all vertebrates and play crucial roles in the regulation of tissue development, cellular differentiation, and the growth and apoptosis of both noncancerous and cancerous cells [4]. Within the context of HCC, miRNAs have been implicated in the modulation of gene expression and have emerged as potential biomarkers for HCC [5]. miR-32-5p has been identified as a pivotal factor in the initiation and progression of numerous cancer types [6]. In light of the observed upregulation of miR-32 in HCC, its functional role in the pathogenesis of disease has been explored [7,8]. However, the precise molecular mechanism of miR-32-5p remains elusive.

Inflammation is widely recognized as a hallmark of cancer and plays a critical role in various stages of oncogenesis. Dysregulation of the NF-κB signaling pathway is intricately linked to all established cancer hallmarks [9–11]. Moreover, overactivation of NF-κB is associated with increased tumor malignancy. These alterations include epithelial-mesenchymal transition (EMT), invasion, angiogenesis, metastasis, and therapy resistance. In addition, NF-κB mediates the inflammatory response during tumor development, and both processes collectively promote genetic and epigenetic modifications that control tumor immune escape mechanisms [12–16]. Glycogen synthase kinase 3 (GSK3) is a highly conserved family of serine/threonine kinases comprising two isoforms, GSK3α (51 kDa) and GSK3β (47 kDa) [17]. Although functional redundancy exists between the two isoforms, most oncological studies have focused on the activity of GSK3β. GSK3β is integral to numerous cellular processes, including cell proliferation, DNA repair mechanisms, cell cycle regulation, signaling cascades, and metabolic pathways. GSK3β is also known to be involved in the regulation of the NF-κB signaling pathway [18]. Bioinformatics tools such as TargetScan have indicated that GSK3β and RelB, both members of the NF-κB signaling pathway, are potential targets of miR-32-5p. However, the detailed regulatory mechanism remains elusive, and further research is needed to understand the complex interplay between miR-32-5p, GSK3β, and the NF-κB axis in th