Jiedu recipe, a compound Chinese herbal medicine, suppresses hepatocellular carcinoma metastasis by inhibiting the release of tumor-derived exosomes in a hypoxic microenvironment

Abstract

ObjectiveTumor-derived exosomes (TDEs) play crucial roles in intercellular communication. Hypoxia in the tumor microenvironment enhances secretion of TDEs and accelerates tumor metastasis. Jiedu recipe (JR), a traditional Chinese medicinal formula, has demonstrated efficacy in preventing the metastasis of hepatocellular carcinoma (HCC). However, the underlying mechanism remains largely unknown. MethodsAnimal experiments were performed to investigate the metastasis-preventing effects of JR. Bioinformatics analysis and in vitro assays were conducted to explore the potential targets and active components of JR. TDEs were assessed using nanoparticle tracking analysis (NTA) and Western blotting (WB). Exosomes derived from normoxic or hypoxic HCC cells (H-TDEs) were collected to establish premetastatic mouse models. JR was intragastrically administered to evaluate its metastasis-preventive effects. WB and lysosomal staining were performed to investigate the effects of JR on lysosomal function and autophagy. Bioinformatics analysis, WB, NTA, and immunofluorescence staining were used to identify the active components and potential targets of JR. ResultsJR effectively inhibited subcutaneous-tumor-promoted lung premetastatic niche development and tumor metastasis. It inhibited the release of exosomes from tumor cells under hypoxic conditions. JR treatment promoted both lysosomal acidification and suppressed secretory autophagy, which were dysregulated in hypoxic tumor cells. Quercetin was identified as the active component in JR, and the epidermal growth factor receptor (EGFR) was identified as a potential target. Quercetin inhibited EGFR phosphorylation and promoted the nuclear translocation of transcription factor EB (TFEB). Hypoxia-impaired lysosomal function was restored, and secretory autophagy was alleviated by quercetin treatment. ConclusionJR suppressed HCC metastasis by inhibiting hypoxia-stimulated exosome release, restoring lysosomal function, and suppressing secretory autophagy. Quercetin acted as a key component of JR and regulated TDE release through EGFR-TFEB signaling. Our study provides a potential strategy for retarding tumor metastasis by targeting H-TDE secretion.