ABSTRACT
Lenvatinib has become the first-line therapy in advanced hepatocellular carcinoma (HCC), but its efficacy is still limited because of the inevitable development of resistance. It has been reported that cellular cholesterol levels are associated with tyrosine kinase inhibitor (TKI) efficacy. Here, we show that betulin, a sterol regulatory element-binding protein 2 (SREBP2) inhibitor, markedly enhances the anti-tumor effect of lenvatinib in HCC both in vitro and in vivo. Our results also show that the combination treatment of lenvatinib and betulin synergistically inhibits the proliferation and clonogenicity of HCC cells. The mRNA and protein expressions of IL-1ß are markedly decreased in HCC cells treated with betulin, while the sensitivity of HCC cells to lenvatinib is enhanced. Moreover, we find that the knockdown of IL-1ß also enhances the efficacy of lenvatinib, and recombinant IL-1ß protein rescues cell viability, which is reduced by lenvatinib in HCC cells. Further mechanistic studies indicate that betulin decreases the level of IL-1ß in HCC cells by inhibiting the mTOR signaling pathway. Finally, the growth of the tumors in xenograft mouse models subjected to combination treatment is significantly suppressed. In summary, our study reveals that the SREBP2 inhibitor betulin sensitizes hepatocellular carcinoma to lenvatinib by inhibiting the mTOR/IL-1ß pathway, which may be a promising therapeutic strategy for patients with HCC.
Subject(s)
Carcinoma, Hepatocellular , Liver Neoplasms , Humans , Animals , Mice , Carcinoma, Hepatocellular/drug therapy , Carcinoma, Hepatocellular/genetics , Carcinoma, Hepatocellular/metabolism , Liver Neoplasms/drug therapy , Liver Neoplasms/genetics , Liver Neoplasms/metabolism , Cell Proliferation , Phenylurea Compounds/pharmacology , Phenylurea Compounds/therapeutic use , TOR Serine-Threonine Kinases/metabolism , Cell Line, TumorABSTRACT
BACKGROUND AND AIMS: Recently, clinical trials of lenvatinib plus pembrolizumab in HCC have displayed an impressive objective response rate. This study aimed to clarify the mechanism for optimal patient selection. APPROACH AND RESULTS: First, in patients with HCC, lenvatinib-treated recurrent tumors had lower programmed death ligand 1 (PD-L1) expression and regulatory T cell (Treg) infiltration compared with matched primary tumors. Consistently, in C57BL/6 wild-type mice receiving anti-programmed cell death 1 (PD-1) therapy, PD-L1 expression and Treg infiltration in s.c. tumors were reduced when adding lenvatinib to the scheme. Mechanistically, on the one hand, FGF receptor 4 (FGFR4) was the most pivotal target in PD-L1 down-regulation by lenvatinib in vitro. Furthermore, lenvatinib reinforced the proteasomal degradation of PD-L1 by blocking the FGFR4-glycogen synthase kinase 3ß axis and rescued the sensitivity of interferon-γ-pretreated HCC cells to T-cell killing by targeting FGFR4. On the other hand, the level of IL-2 increased after anti-PD-1 treatment, but IL-2-mediated Treg differentiation was blocked by lenvatinib through targeting FGFR4 to restrain signal transducer and activator of transcription 5 (STAT5) phosphorylation. By regulating the variations in the number of Tregs and the tumor FGFR4 level in C57BL/6-forkhead box protein P3 (Foxp3DTR ) mice, we found that high levels of FGFR4 and Treg infiltration sensitized tumors to the combination treatment. Finally, high levels of FGFR4 and Foxp3 conferred immune tolerance but better response to the combined therapy in patient cohorts. CONCLUSIONS: Lenvatinib reduced tumor PD-L1 level and Treg differentiation to improve anti-PD-1 efficacy by blocking FGFR4. Levels of FGFR4 expression and Treg infiltration in tumor could serve as biomarkers for screening patients with HCC using lenvatinib plus anti-PD-1 combination therapy.
Subject(s)
Carcinoma, Hepatocellular/drug therapy , Carcinoma, Hepatocellular/immunology , Immunity , Liver Neoplasms/drug therapy , Liver Neoplasms/immunology , Phenylurea Compounds/administration & dosage , Programmed Cell Death 1 Receptor/antagonists & inhibitors , Protein Kinase Inhibitors/administration & dosage , Quinolines/administration & dosage , Receptor, Fibroblast Growth Factor, Type 4/metabolism , Signal Transduction/drug effects , Adult , Aged , Animals , Antibodies, Monoclonal/administration & dosage , B7-H1 Antigen/metabolism , Carcinoma, Hepatocellular/metabolism , Carcinoma, Hepatocellular/pathology , Cell Differentiation/drug effects , Cell Line, Tumor , Cohort Studies , Disease Models, Animal , Drug Synergism , Female , Humans , Liver Neoplasms/metabolism , Liver Neoplasms/pathology , Male , Mice , Mice, Inbred C57BL , Mice, Transgenic , Middle Aged , Neoplasm Recurrence, Local/immunology , Neoplasm Recurrence, Local/metabolism , Programmed Cell Death 1 Receptor/immunology , Signal Transduction/immunology , T-Lymphocytes, Regulatory/immunology , Treatment OutcomeABSTRACT
BACKGROUND: The advent of immune checkpoint inhibitors (ICIs) has revolutionized the therapeutic options of hepatobiliary malignancies. However, the clinical benefit provided by immunotherapy seems limited to a small subgroup of patients with hepatobiliary malignancies. The identification of reliable predictors of the response to immunotherapy is urgently needed. DATA SOURCES: Literature search was conducted in PubMed for relevant articles published up to May 2022. Information of clinical trials was obtained from https://clinicaltrials.gov/. RESULTS: Biomarkers for ICI response of hepatobiliary malignancies remain in the exploration stage and lack compelling evidence. Tumor programmed death-ligand 1 (PD-L1) expression is the most widely studied biomarker in hepatocellular carcinoma (HCC) and biliary tract cancers (BTCs), but there are conflicting results on its predictive potential. Tumor mutational burden (TMB) is generally low both in HCC and BTCs, and the clinical trials of TMB are rare in hepatobiliary malignancies. Promisingly, mismatch repair deficiency (dMMR)/high microsatellite instability (MSI-H) may be a predictive biomarker of response to anti-PD-1 therapy in BTCs. Furthermore, some emerging biomarkers, such as gut microbiota, show predictive potential in the preliminary studies. Radiomics and liquid-biopsy biomarkers, including circulating tumor cells, circulating tumor DNA (ctDNA) and exosomal PD-L1 provide a quick and non-invasive approach for monitoring the ICI response, showing a new promising direction. CONCLUSIONS: Multiple potential biomarkers for predicting ICI response of hepatobiliary malignancies have been explored and tried to apply in clinic. Yet there is no robust evidence to prove their clinical value in predicting immunotherapeutic response for patients with hepatobiliary malignancies. The identification of predictors for response to ICIs is an urgent need and major challenge. Further studies are warranted to validate the role of emerging biomarkers in predicting immunotherapeutic responses.
Subject(s)
Carcinoma, Hepatocellular , Liver Neoplasms , B7-H1 Antigen , Biomarkers, Tumor/genetics , Biomarkers, Tumor/metabolism , Carcinoma, Hepatocellular/drug therapy , Carcinoma, Hepatocellular/genetics , Humans , Immune Checkpoint Inhibitors/adverse effects , Immunotherapy/methods , Liver Neoplasms/drug therapy , Liver Neoplasms/geneticsABSTRACT
Recent studies have revealed the significant dysregulation of m6A level in peripheral blood in several cancer types and its value in diagnosis. Nonetheless, a biomarker for accurate screening of multiple cancer types has not been established based on the perspective of m6A modification. In this study, we aimed to develop a serum diagnostic signature based on the m6A target miRNAs for the mass detection of cancer. A total of 14965 serum samples with 12 cancer types were included. Based on training cohort (n=7299), we developed the m6A-miRNAs signature using a support vector machine algorithm for cancer detection. The m6A-miRNAs signature showed high accuracy, and its area under the curve (AUC) in the training, internal validation and external validation cohort reached 0.979 (95%CI 0.976 - 0.982), 0.976 (95%CI 0.973 - 0.979) and 0.936 (95%CI 0.922 - 0.951), respectively. In the performance of distinguishing cancer types, the m6A-miRNAs signature showed superior sensitivity in each cancer type and presented a satisfactory AUC in identifying lung cancer, gastric cancer and hepatocellular carcinoma. Additionally, the diagnostic performance of m6A-miRNAs was not interfered by the gender, age and benign disease. In short, this study revealed the value of serum circulating m6A miRNAs in cancer detection and provided a new direction and strategy for the development of novel biomarkers with high accuracy, low cost and less invasiveness for mass cancer screening, such as RNA modification.
Subject(s)
Adenosine/analogs & derivatives , Biomarkers, Tumor , Circulating MicroRNA , MicroRNAs/genetics , Neoplasms/diagnosis , Neoplasms/genetics , Adenosine/metabolism , Computational Biology/methods , Diagnosis, Differential , Gene Expression Profiling , Humans , Liquid Biopsy , MicroRNAs/blood , Neoplasms/blood , Prognosis , ROC Curve , Reproducibility of ResultsABSTRACT
Tumor-associated macrophages (TAMs) are crucial components of the tumor microenvironment. They play vital roles in hepatocellular carcinoma (HCC) progression. However, the interactions between TAMs and HCC cells have not been fully characterized. In this study, TAMs were induced using human monocytic cell line THP-1 cells in vitro to investigate their functions in HCC progression. S100 calcium-binding protein A9 (S100A9), an inflammatory microenvironment-related secreted protein, was identified to be significantly upregulated in TAMs. S100A9 expression in tumor tissues was associated with poor survival of HCC patients. It could enhance the stem cell-like properties of HepG2 and MHCC-97H cells by activating nuclear factor-kappa B signaling pathway through advanced glycosylation end product-specific receptor in a Ca2+ -dependent manner. Furthermore, we found that, after treatment with S100A9, HepG2 and MHCC-97H cells recruited more macrophages via chemokine (CC motif) ligand 2, which suggests a positive feedback between TAMs and HCC cells. Taken together, our findings reveal that TAMs could upregulate secreted protein S100A9 and enhance the stem cell-like properties of HCC cells and provide a potential therapeutic target for combating HCC.
Subject(s)
Calgranulin B/physiology , Carcinoma, Hepatocellular/pathology , Liver Neoplasms/pathology , Neoplastic Stem Cells/physiology , Tumor-Associated Macrophages/physiology , Animals , Cell Line, Tumor , Humans , Mice , Mice, Inbred BALB C , NF-kappa B/physiology , Receptor for Advanced Glycation End Products/physiologyABSTRACT
BACKGROUND: Mitochondrial dynamics plays an important role in tumour progression. However, how these dynamics integrate tumour metabolism in hepatocellular carcinoma (HCC) metastasis is still unclear. METHODS: The mitochondrial fusion protein mitofusin-1 (MFN1) expression and its prognostic value are detected in HCC. The effects and underlying mechanisms of MFN1 on HCC metastasis and metabolic reprogramming are analysed both in vitro and in vivo. RESULTS: Mitochondrial dynamics, represented by constant fission and fusion, are found to be associated with HCC metastasis. High metastatic HCC displays excessive mitochondrial fission. Among genes involved in mitochondrial dynamics, MFN1 is identified as a leading downregulated candidate that is closely associated with HCC metastasis and poor prognosis. While promoting mitochondrial fusion, MFN1 inhibits cell proliferation, invasion and migration capacity both in vitro and in vivo. Mechanistically, disruption of mitochondrial dynamics by depletion of MFN1 triggers the epithelial-to-mesenchymal transition (EMT) of HCC. Moreover, MFN1 modulates HCC metastasis by metabolic shift from aerobic glycolysis to oxidative phosphorylation. Treatment with glycolytic inhibitor 2-Deoxy-D-glucose (2-DG) significantly suppresses the effects induced by depletion of MFN1. CONCLUSIONS: Our results reveal a critical involvement of mitochondrial dynamics in HCC metastasis via modulating glucose metabolic reprogramming. MFN1 may serve as a novel potential therapeutic target for HCC.
Subject(s)
Carcinoma, Hepatocellular/metabolism , Deoxyglucose/pharmacology , GTP Phosphohydrolases/genetics , Glucose/metabolism , Liver Neoplasms/metabolism , Mitochondrial Membrane Transport Proteins/genetics , Carcinoma, Hepatocellular/genetics , Carcinoma, Hepatocellular/pathology , Cell Proliferation/drug effects , Epithelial-Mesenchymal Transition/drug effects , GTP Phosphohydrolases/metabolism , Gene Expression Regulation, Neoplastic/drug effects , Glycolysis/drug effects , Humans , Liver Neoplasms/genetics , Liver Neoplasms/pathology , Mitochondria/genetics , Mitochondria/metabolism , Mitochondrial Dynamics/genetics , Mitochondrial Membrane Transport Proteins/metabolism , Neoplasm Metastasis , Oxidative Phosphorylation/drug effects , Reactive Oxygen Species/metabolism , Signal Transduction/drug effectsABSTRACT
BACKGROUND: Immune checkpoint inhibitor monotherapy did not show superiority of survival over standard therapy in advanced hepatocellular carcinoma. The combination immunotherapy including dual immune checkpoint inhibitors or combined with anti-VEGF agents have become a trend, but not fully evaluated. This study aimed to evaluate and compare distinct combination immunotherapy on efficacy in advanced hepatocellular carcinoma. METHODS: PubMed, Embase, Web of Science and Cochrane databases were systematically searched from inception to January 31, 2022. The primary endpoints were overall objective response rate (ORR), disease control rate (DCR), six-month progression-free survival rate (PFSR6m) and one-year overall survival rate (OSR1y). RESULTS: 11 studies with 16 independent cohorts and 3342 patients were included in the meta-analysis. Compared with first-line sorafenib, combination immunotherapy resulted in a significant improvement in ORR (RR, 2.74; 95%CI, 1.55-4.85; p = 0.0006), PFS (HR, 0.57; 95%CI, 0.49-0.65; p<0.0001) and OS (HR, 0.65; 95%CI, 0.52-0.82; p = 0.0002). Based on RECIST 1.1, the pooled ORR, PFSR6m and OSR1y for combination immunotherapy were 24.6% (95%CI: 20.3%-29.6%), 42.0% (95%CI: 34.2%-50.3%) and 61.8% (95%CI: 57.7%-65.7%), respectively. In distinct combination regimens, PD-1/L1 inhibitors plus anti-VEGF agents showed a significant superiority of clinical benefit than PD-1/L1 inhibitors plus CTLA-4 inhibitors (ORR: 25.2% vs 23.4%, p = 0.033; PFSR6m: 47.4% vs 23.2%, p<0.001; OSR1y: 65.1% vs 55.0%, p = 0.001). CONCLUSIONS: This study was the first meta-analysis to demonstrate the better survival benefit and tolerable toxicity of combination immunotherapy than standard therapy in advanced hepatocellular carcinoma. Compared with PD-1/L1 inhibitors plus CTLA-4 inhibitors, the regimens of PD-1/L1 inhibitors plus anti-VEGF agents may be associated with a significantly better clinical benefit. The difference in long-term survival and response population between two distinct combination regimens required further exploration.
Subject(s)
Carcinoma, Hepatocellular , Liver Neoplasms , Lung Neoplasms , Humans , Carcinoma, Hepatocellular/drug therapy , Immune Checkpoint Inhibitors/therapeutic use , Immunotherapy/methods , Liver Neoplasms/drug therapy , Lung Neoplasms/drug therapy , Programmed Cell Death 1 Receptor , Vascular Endothelial Growth Factor A/metabolismABSTRACT
Interleukin-6 (IL-6), an important inflammatory cytokine, is a key factor regulating cancer metastasis. Cancer cells can modulate their tumorigenic abilities by sorting specific microRNAs (miRNAs) as exosomes into the tumor microenvironment. The relationship between IL-6 and exosomal miRNAs related to hepatocellular carcinoma (HCC) metastasis remains to be elucidated. We examined the metastatic ability of HCC cells after IL-6 treatment and found that miR-133a-3p was sorted into exosomes after IL-6 stimulation and was subsequently released into the tumor microenvironment. In vitro analysis confirmed that exosomal miR-133a-3p acted as a tumor suppressor in HCC. Bioinformatic analysis revealed several signaling pathways and hub genes (CREB1, VCP, CALM1, and YES1) regulated by miR-133a-3p. Survival curves further verified the important roles of hub genes in the prognosis of patients with HCC. It is envisaged that the IL-6/miR-133a-3p axis may be related to the activation of CREB1, VCP, CALM1, and YES1. Our findings provide new insights into the role of exosomal miRNA-mediated tumor progression under inflammatory conditions.
ABSTRACT
BACKGROUND: Oxidative stress is a highly active metabolic process in the liver, that poses great threats to disseminated tumor cells during their colonization. Here, we aimed to investigate how colorectal cancer (CRC) cells overcome lipid peroxidation to sustain their metastatic colonization in the liver. METHODS: Orthotopic colorectal liver metastasis (CRLM) and CRC liver colonization mouse models were constructed to determine the roles of lipid peroxidation and AADAC in CRC liver colonization. The levels of lipid peroxidation were detected in cells or tissues. AADAC overexpression in LMs and its clinical relevance were analyzed. The oncogenic role of AADAC in CRC liver colonization was evaluated in cell experiments. RESULTS: Compared with primary tumors (PTs), liver metastases (LMs) showed significantly lower glutathione to oxidized glutathione (GSH/GSSG) ratio and higher malondialdehyde (MDA) levels in CRLM patients and orthotopic mouse models. Inhibition of lipid peroxidation by liproxstatin-1 promoted CRC liver colonization in mouse models. RNA-seq results revealed AADAC as the most significantly upregulated lipid metabolism related gene in LMs compared with PTs. Analyses of datasets and patient and mouse model samples confirmed that AADAC was upregulated in LMs compared with PTs, and was correlated with poor prognosis. AADAC promoted cell proliferation, and facilitated liver colonization in a mouse model by reducing ROS accumulation, which led to lipid peroxidation and ferroptosis. Mechanistically, AADAC upregulated SLC7A11 by activating NRF2 to inhibit lipid peroxidation, thereby protecting metastatic cells from ferroptosis. CONCLUSIONS: AADAC protects metastatic CRC cells from ferroptosis by inhibiting lipid peroxidation in an SLC7A11-dependent manner, thus effectively promoting their metastatic colonization and growth in the liver. Together, our findings suggest that AADAC can act as a prognostic indicator and potential therapeutic target for CRLM.
Subject(s)
Colorectal Neoplasms , Ferroptosis , Liver Neoplasms , Amino Acid Transport System y+ , Animals , Carboxylic Ester Hydrolases , Colorectal Neoplasms/genetics , Glutathione/metabolism , Glutathione Disulfide/metabolism , Lipid Peroxidation , Liver Neoplasms/genetics , Malondialdehyde , Mice , NF-E2-Related Factor 2/metabolism , Reactive Oxygen Species/metabolismABSTRACT
Aberrant activation of receptor tyrosine kinases (RTKs) and the subsequent metabolic reprogramming play critical roles in cancer progression. Our previous study has shown that Golgi membrane protein 1 (GOLM1) promotes hepatocellular carcinoma (HCC) metastasis by enhancing the recycling of RTKs. However, how this RTK recycling process is regulated and coupled with RTK degradation remains poorly defined. Here, we demonstrate that cholesterol suppresses the autophagic degradation of RTKs in a GOLM1-dependent manner. Further mechanistic studies reveal that GOLM1 mediates the selective autophagy of RTKs by interacting with LC3 through an LC3-interacting region (LIR), which is regulated by a cholesterol-mTORC1 axis. Lowering cholesterol by statins improves the efficacy of multiple tyrosine kinase inhibitors (TKIs) in vivo. Our findings indicate that cholesterol serves as a signal to switch GOLM1-RTK degradation to GOLM1-RTK recycling and suggest that lowering cholesterol by statin may be a promising combination strategy to improve the TKI efficiency in HCC.
Subject(s)
Carcinoma, Hepatocellular , Liver Neoplasms , Autophagy , Carcinoma, Hepatocellular/pathology , Cholesterol , Humans , Liver Neoplasms/pathology , Membrane Proteins/metabolism , Receptor Protein-Tyrosine KinasesABSTRACT
The immunosuppressive microenvironment plays an important role in tumor progression and immunotherapy responses. Golgi membrane protein 1 (GOLM1) is correlated to hepatocellular carcinoma (HCC) progression and metastasis. However, little is known about the role of GOLM1 in regulating the immunosuppressive environment and its impact on immunotherapeutic efficacy in HCC. In this study, GOLM1 was positively correlated with infiltrating tumor-associated macrophages (TAMs) expressed high levels of programmed death-ligand 1 (PD-L1) and CD8+ T cell suppression in HCC tissues. Both gain- and loss-of-function studies determined a close correlation between GOLM1 and immunosuppression. In the mechanism, GOLM1 promoted COP9 signalosome 5-mediated PD-L1 deubiquitination in HCC cells and increased the transport of PD-L1 into exosomes via suppression of Rab27b expression. Furthermore, co-culture with exosomes derived from HCC cells upregulated the expression of PD-L1 on macrophages. Zoledronic acid in combination with anti-PD-L1 therapy reduced PD-L1+ TAMs infiltration and alleviated CD8+ T cell suppression, resulting in tumor growth inhibition in the mouse HCC model. Together, our study unveils a mechanism by which GOLM1 induces CD8+ T cells suppression through promoting PD-L1 stabilization and transporting PD-L1 into TAMs with exosome dependent. Targeting PD-L1+ TAM could be a novel strategy to enhance the efficacy of anti-PD-L1 therapy in HCC.
Subject(s)
CD8-Positive T-Lymphocytes/immunology , Carcinoma, Hepatocellular/immunology , Liver Neoplasms, Experimental/immunology , Membrane Proteins/immunology , Neoplasm Proteins/immunology , Programmed Cell Death 1 Receptor/immunology , Tumor-Associated Macrophages/immunology , Animals , Carcinoma, Hepatocellular/genetics , Liver Neoplasms, Experimental/genetics , Male , Membrane Proteins/genetics , Mice , Neoplasm Proteins/genetics , Programmed Cell Death 1 Receptor/geneticsABSTRACT
BACKGROUND: Dysregulation of both mitochondrial biogenesis and mitophagy is critical to sustain oncogenic signaling pathways. However, the mechanism of mitophagy in promoting hepatocellular carcinoma (HCC) progression remains poorly understood. In this study, we investigated the clinical significance and biological involvement of mitochondrial inner membrane protein STOML2 in HCC. METHODS: STOML2 was identified by gene expression profiles of HCC tissues and was measured in tissue microarray and cell lines. Gain/loss-of-function experiment was applied to study the biological function of STOML2 in HCC. Flow cytometry, Western blotting, laser confocal microscopy, transmission electron microscopy, and co-immunoprecipitation were used to detect and analyze mitophagy. ChIP and luciferase reporter assay were conducted to evaluate the relationship between STOML2 and HIF-1α. The sensitivity to lenvatinib was assessed in HCC both in vitro and in vivo. RESULTS: Increased expression of STOML2 was found in HCC compared with paired peritumoral tissues. It was more significant in HCC with metastasis and correlated with worse overall survival and higher probability of recurrence after hepatectomy. Upregulation of STOML2 accelerated HCC cells colony formation, migration and invasion. Mechanically, TCGA dataset-based analysis showed enrichment of autophagy-related pathways in STOML2 highly-expressed HCC. Next, STOML2 was demonstrated to interact and stabilize PINK1 under cellular stress, amplify PINK1-Parkin-mediated mitophagy and then promote HCC growth and metastasis. Most interestingly, HIF-1α was upregulated and transcriptionally increased STOML2 expression in HCC cells under the treatment of lenvatinib. Furthermore, higher sensitivity to lenvatinib was found in HCC cells when STOML2 was downregulated. Combination therapy with lenvatinib and mitophagy inhibitor hydroxychloroquine obtained best efficacy. CONCLUSIONS: Our findings suggested that STOML2 could amplify mitophagy through interacting and stabilizing PINK1, which promote HCC metastasis and modulate the response of HCC to lenvatinib. Combinations of pharmacologic inhibitors that concurrently block both angiogenesis and mitophagy may serve as an effective treatment for HCC.
Subject(s)
Antineoplastic Agents/pharmacology , Blood Proteins/metabolism , Carcinoma, Hepatocellular/metabolism , Liver Neoplasms/metabolism , Membrane Proteins/metabolism , Mitophagy , Phenylurea Compounds/pharmacology , Protein Kinases/metabolism , Quinolines/pharmacology , Animals , Antineoplastic Agents/therapeutic use , Apoptosis/drug effects , Blood Proteins/analysis , Carcinoma, Hepatocellular/drug therapy , Carcinoma, Hepatocellular/pathology , Cell Line, Tumor , Liver Neoplasms/drug therapy , Liver Neoplasms/pathology , Membrane Proteins/analysis , Mice, Inbred BALB C , Mice, Nude , Mitophagy/drug effects , Neoplasm Invasiveness/pathology , Phenylurea Compounds/therapeutic use , Protein Kinases/analysis , Quinolines/therapeutic useABSTRACT
Sorafenib is the first approved systemic therapy for advanced hepatocellular carcinoma (HCC) and is the first-line choice in clinic. Sustained activation of receptor tyrosine kinases (RTKs) is associated with low efficacy of sorafenib in HCC. Activation of liver X receptor (LXR) has been reported to inhibit some RTKs. In this study, we found that the LXR agonist enhanced the anti-tumor activity of sorafenib in a subset of HCC cells with high LXR-ß/α gene expression ratio. Mechanically, the activation of LXR suppressed sorafenib dependent recruitment of MET and epidermal growth factor receptor (EGFR) in lipid rafts through cholesterol efflux. Our findings imply that LXR agonist can serve as a potential sensitizer to enhance the anti-tumor effect of sorafenib.
Subject(s)
Antineoplastic Agents/pharmacology , Carcinoma, Hepatocellular/metabolism , Liver Neoplasms/metabolism , Liver X Receptors/agonists , Protein Kinase Inhibitors/pharmacology , Proto-Oncogene Proteins c-met/antagonists & inhibitors , Sorafenib/pharmacology , Animals , Antineoplastic Agents/therapeutic use , Carcinoma, Hepatocellular/drug therapy , Carcinoma, Hepatocellular/etiology , Carcinoma, Hepatocellular/pathology , Cell Line, Tumor , Cell Proliferation/drug effects , Cholesterol/metabolism , Disease Models, Animal , Dose-Response Relationship, Drug , Drug Resistance, Neoplasm , ErbB Receptors/antagonists & inhibitors , Humans , Immunohistochemistry , Liver Neoplasms/drug therapy , Liver Neoplasms/etiology , Liver Neoplasms/pathology , Male , Mice , Protein Binding , Protein Kinase Inhibitors/therapeutic use , Sorafenib/therapeutic use , Xenograft Model Antitumor AssaysABSTRACT
BACKGROUND: The propensity of the activated neutrophils to form extracellular traps (NETs) is demonstrated in multiple inflammatory conditions. In this study, we investigated the roles of NETs in metastasis of hepatocellular carcinoma (HCC) and further explored the underlying mechanism of how NETs affect metastasis as well as the therapeutic value. METHODS: The neutrophils were isolated from the blood of human HCC patients and used to evaluate the formation of NETs. The expression of NET markers was detected in tumor specimens. A LPS-induced NET model was used to investigate the role of NETs on HCC metastasis. RNA-seq was performed to identify the key molecular event triggered by NETs, and their underlying mechanism and therapeutic significance were explored using both in vitro and in vivo assays. RESULTS: NET formation was enhanced in neutrophils derived from HCC patients, especially those with metastatic HCCs. NETs trapped HCC cells and subsequently induced cell-death resistance and enhanced invasiveness to trigger their metastatic potential, which was mediated by internalization of NETs into trapped HCC cells and activation of Toll-like receptors TLR4/9-COX2 signaling. Inhibition of TLR4/9-COX2 signaling abrogated the NET-aroused metastatic potential. A combination of DNase 1 directly wrecking NETs with anti-inflammation drugs aspirin/hydroxychloroquine effectively reduced HCC metastasis in mice model. CONCLUSIONS: NETs trigger tumorous inflammatory response and fuel HCC metastasis. Targeting NETs rather than neutrophils themselves can be a practice strategy against HCC metastasis.
Subject(s)
Carcinoma, Hepatocellular/pathology , Extracellular Traps/immunology , Inflammation/pathology , Liver Neoplasms/pathology , Animals , Carcinoma, Hepatocellular/immunology , Hep G2 Cells , Humans , Inflammation/immunology , Liver Neoplasms/immunology , Male , Mice, Inbred C57BL , Neoplasm Metastasis/immunology , Neoplasm Metastasis/pathologyABSTRACT
Metabolic reprogramming plays an important role in supporting tumor growth. However, little is known about the metabolic alterations that promote cancer metastasis. In this study, we identify acyl-CoA thioesterase 12 (ACOT12) as a key player in hepatocellular carcinoma (HCC) metastasis. The expression of ACOT12 is significantly down-regulated in HCC tissues and is closely associated with HCC metastasis and poor survival of HCC patients. Gain- and loss-of-function studies demonstrate that ACOT12 suppresses HCC metastasis both in vitro and in vivo. Further mechanistic studies reveal that ACOT12 regulates the cellular acetyl-CoA levels and histone acetylation in HCC cells and that down-regulation of ACOT12 promotes HCC metastasis by epigenetically inducing TWIST2 expression and the promotion of epithelial-mesenchymal transition. Taken together, our findings link the alteration of acetyl-CoA with HCC metastasis and imply that ACOT12 could be a prognostic marker and a potential therapeutic target for combating HCC metastasis.
Subject(s)
Acetyl Coenzyme A/metabolism , Carcinoma, Hepatocellular/metabolism , Epithelial-Mesenchymal Transition/genetics , Liver Neoplasms/metabolism , Thiolester Hydrolases/metabolism , Acetyl Coenzyme A/genetics , Animals , Carcinoma, Hepatocellular/genetics , Cell Line, Tumor , Epigenesis, Genetic/genetics , HEK293 Cells , Humans , Liver Neoplasms/genetics , Male , Mice , Mice, Inbred BALB C , Mice, Nude , Thiolester Hydrolases/geneticsABSTRACT
Histone methyltransferases are important determinants of the initiation and progression of hepatocellular carcinoma (HCC) and represent promising therapeutic targets. However, whether the expression profile of multiple histone methyltransferases represents a poorer prognosis is entirely unknown. The aim of the present study was to investigate the association between histone methylation and HCC phenotype, and the prognostic value of combining expression levels of SET domain-containing protein 8 (SET8) with protein arginine methyltransferase 5 (PRMT5) in patients with HCC following curative resection. The retrospective study included 195 consecutive patients who had undergone hepatectomy for HCC. Immunohistochemical staining for SET8 and PRMT5 was performed on paraffin-embedded tumor tissue microarrays. Expression was analyzed for correlations with clinicopathological features, marker co-expression and patients' survival by univariate and multivariate analyses. Positive SET8 expression was noted in 104 patients (53.3%), and was associated with PRMT5 expression (n=106, 54.4%, P<0.05). Immunohistochemical analysis demonstrated that high expression of SET8 and PRMT5 was significantly associated with poor overall survival (OS, P<0.001) and time to recurrence (TTR, P<0.001). Multivariate Cox analysis revealed that SET8 and PRMT5, along with vascular invasion, tumor size and tumor number, were independent prognostic factors for OS and TTR. The combination of SET8 and PRMT5 demonstrated an improved capacity to predict patient mortality and disease recurrence (P=0.002 and P=0.004, respectively), particularly for the prediction of early recurrence (P<0.001). In conclusion, high expression of SET8 combined with PRMT5 was associated with a high rate of recurrence and poor survival in patients with HCC. The independent pattern of histone methylation represents a novel insight into tumor progression and therapeutic targets for HCC.