Reply to: "Myofibroblast YAP/TAZ is dispensable for liver fibrosis in mice"

Targeted activation of HNF4α/HGF1/FOXA2 reverses hepatic fibrosis via exosome-mediated delivery of CRISPR/dCas9-SAM system

Aim: Hepatic fibrosis is one of the most common conditions worldwide, and yet no effective antifibrotic therapy is available. This study aimed to reverse hepatic fibrosis via exosome-mediated delivery of the CRISPR/dCas9-SAM system. Materials & methods: The authors constructed a modified-exosome delivery system targeting hepatic stellate cells (HSCs), and constructed the CRISPR/dCas9-SAM system inducing HSCs convert into hepatocyte-like cells in vitro and in vivo. Results: RBP4-modified exosomes could efficiently load and deliver the CRISPR/dCas9 system to HSCs. The in vitro CRISPR/dCas9 system induced the conversion from HSCs to hepatocyte-like cells via targeted activation of HNF4α/HGF1/FOXA2 genes. Importantly, in vivo targeted delivery of this system significantly attenuated CCl₄-induced hepatic fibrosis. Conclusion: Targeted activation of HNF4α/HGF1/FOXA2 reverses hepatic fibrosis via exosome-mediated delivery of the CRISPR/dCas9-SAM system, which provides a feasible antifibrotic strategy.

Deubiquitinating enzyme JOSD2 promotes hepatocellular carcinoma progression through interacting with and inhibiting CTNNB1 degradation

Although a variety of molecular targets have been identified, hepatocellular carcinoma (HCC) remains among the leading causes of death. As functions of they deubiquitinating enzyme Josephin domain containing 2 (JOSD2) in cancers are still poorly understood, we investigated its function and molecular mechanism in the regulation of HCC progression. Here, we indicated that JOSD2 expression is elevated in patient samples with HCC and positively associated with poor prognosis. Moreover, the promoting roles of JOSD2 in HCC cell survival, migration, and invasion were determined using in vitro models. Importantly, a mechanistic study revealed that JOSD2 binds to and decreases the ubiquitination level of catenin beta 1 (CTNNB1), a key component of Wnt signaling, thereby augmenting Wnt pathway transduction. Furthermore, a series of rescue experiments confirmed the significance of CTNNB1 in the modulation of HCC progression by JOSD2. Our study uncovered JOSD2 as a novel prognostic marker for patients with HCC and identified CTNNB1 as a pivotal partner and downstream target protein of JOSD2, which may aid in the development of JOSD2 as a promising molecular target for HCC treatment.