249 Engineered mesenchymal stem cell extracellular vesicles loaded with miRNA-34a modulate stemness biomarkers in the CD133+/CD90+ liver cancer stem cell subpopulation linked to nonalcoholic steatohepatitis.

Introduction/Objective Nonalcoholic fatty liver disease (NAFLD) spans from simple steatosis to severe liver injury, with the inflammatory phase known as nonalcoholic steatohepatitis (NASH). NASH can progress to cirrhosis and may require a liver transplant to prevent mortality. NAFLD affects approximately 25% of the global population, with the highest prevalence observed in the Middle East, where rates reach about 31.79%. NASH, a severe form of NAFLD, involves various cell types—epithelial, progenitor, hepatic stellate, endothelial, and inflammatory cells—that contribute to its progression. Early identification and targeted treatment of NAFLD/NASH are crucial for reducing morbidity and mortality. However, aside from imaging methods like MRI elastography, there are no reliable minimally invasive diagnostic tools for accurate diagnosis and stratification. Methods/Case Report Liver cancer stem cell (LCSC) subpopulations exhibit resistance to chemotherapy and are linked to metastatic hepatocellular carcinoma (HCC). This phenomenon is frequently observed in patients infected with the hepatitis C virus (HCV), particularly those who also struggle with obesity or alcohol abuse. However, there is a need for further exploration into the role of LCSC stemness biomarkers and signaling pathways for the early identification and targeted treatment of NAFLD/NASH. Results Mesenchymal stem cells (MSCs) are well-known for their remarkable self-renewal capabilities, exceptional compatibility with biological tissues, and low tendency to provoke immune responses. These distinctive characteristics position them as a pioneering therapeutic option for liver diseases, presenting promising opportunities for innovative solutions in regenerative medicine. In this study, we employed cell-based therapies utilizing extracellular vesicles (EVs) derived from mesenchymal stem cells (MSCs) (MSC-EVs). These cell-free vehicles exhibit low immunogenicity and were utilized to modulate the stem cell-related molecular markers of the LCSC subpopulation, which are linked to the initiation and progression of NAFLD. Furthermore, we engineered EVs loaded with miRNA-34a, a tumor suppressor specifically targeting the CD133+/CD90+ LCSC subpopulation, which were isolated via FACS from HCC animal models developed with or without NAFLD. This approach was found to affect several stemness biomarkers, including Notch1, Notch4, Nanog, p-S6 kinase, β-catenin, and Stat3, in both in vitro and in vivo settings. These results suggest that engineered EVs loaded with miRNA-34a may represent a promising MSC-based therapeutic strategy for treating NAFLD/NASH. These results suggest that engineered EVs loaded with miRNA-34a may represent a promising MSC-based therapeutic strategy for treating NAFLD/NASH. Conclusion Our data conclude that engineered EVs loaded with miRNA-34a may play a vital role in the therapeutic strategy for treating NAFLD/NASH.