Targeting 5-Hydroxytryptamine receptor 1A in portal vein to decrease portal hypertension.

BACKGROUNDS & AIMS: Portal hypertension (PH) is one of the most frequent complications of chronic liver disease. The peripheral 5-Hydroxytryptamine (5-HT) level was increased in cirrhotic patients. We aimed to elucidate the function and mechanism of 5-HT receptor 1A (HTR1A) in portal vein (PV) on PH. METHODS: PH models were induced by thioacetamide (TAA) injection, bile duct ligation (BDL) or partial portal vein ligation (PPVL). HTR1A expression was detected using real-time PCR, in situ hybridization and immunofluorescence staining. In situ intraportal infusion was employed to assess the effects of 5-HT, the HTR1A agonist 8-OH-DPAT, and the HTR1A antagonist WAY-100635 on portal pressure (PP). Htr1a knock-out (Htr1a-/-) rats and vascular smooth muscle cell (VSMC)-specific Htr1a knock-out (Htr1aΔVSMC) mice were utilized to confirm the regulatory role of HTR1A on PP. RESULTS: HTR1A expression was significantly increased in the hypertensive PV of PH model rats and cirrhotic patients. Additionally, 8-OH-DPAT increased but WAY-100635 decreased PP in rats, without affecting liver fibrosis and systemic hemodynamics. Furthermore, 5-HT or 8-OH-DPAT directly induced the contraction of isolated PVs. Genetic deletion of Htr1a in rats and VSMCs-specific Htr1a knock-out in mice prevented the development of PH. Moreover, 5-HT triggered the cAMP pathway-mediated PVSMCs contraction via HTR1A in PV. We also confirmed alverine as an HTR1A antagonist and demonstrated its capacity to decrease PP in TAA-, BDL-, and PPVL-induced portal hypertensive rats. CONCLUSIONS: Our findings reveal that 5-HT promotes PH by inducing the contraction of PV, and identify HTR1A as a promising therapeutic target for attenuating PH. As an HTR1A antagonist, alverine is expected to become a candidate for clinical PH treatment.

The α-1 Adrenergic Receptor Antagonist Doxazosin Attenuates Liver Fibrosis by Alleviating Sinusoidal Capillarization and Liver Angiogenesis.

Liver fibrosis and cirrhosis, which are caused by chronic liver injury, represent common and intractable clinical challenges of global importance. However, effective therapeutics are lacking. Therefore, the study examines the effect of doxazosin on liver fibrosis. Carbon tetrachloride (CCl4) is injected into mice to establish a liver fibrosis model. Doxazosin (5 and 10 mg/kg) is administered daily by gavage. HE staining, Masson staining, Sirius Red staining, scanning electron microscopy, western blotting, real-time PCR, and immunofluorescence analysis are performed to estimate liver fibrosis and sinusoidal capillarization in mice. Cell Counting Kit-8 assays, western blotting, immunofluorescence analysis, tube formation, and transwell migration assays are performed on human umbilical vein endothelial cells (HUVECs) and human hepatic sinusoidal endothelial cells (HHSECs) to elucidate the potential mechanism of doxazosin. Doxazosin alleviates liver fibrosis and sinusoidal capillarization in CCl4-induced mice. Angiogenesis is attenuated by doxazosin in HUVECs and HHSECs. This study demonstrates that doxazosin attenuated liver fibrosis by alleviating sinusoidal capillarization and liver angiogenesis.

Depletion of Tgfbr2 in hepatocytes alleviates liver fibrosis and restores hepatic function in fibrotic mice.

OBJECTIVES: Previous studies have demonstrated the pivotal role of transforming growth factor (TGF)-ß signaling in activating hepatic stellate cells during liver fibrosis. In this study we aimed to demonstrate the effects and underlying mechanism of TGF-ß signaling in hepatocytes on hepatic fibrogenesis. METHODS: Hepatocyte-specific Tgfbr2-knockout (Tgfbr2HKO ) mice were generated by AAV8-TBG-Cre injection via the tail vein of Tgfbr2f/f mice. CCl4 was injected intraperitoneally twice a week for 4 weeks to establish the fibrotic mouse model. The expression of the fibrogenesis markers was evaluated by immunohistochemistry, western blot, and real-time polymerase chain reaction (PCR). RNA-seq analysis was used to detect the transcriptional profiles of primary hepatocytes isolated from Tgfbr2HKO mice and control mice. RESULTS: The expression of TßR2 (Tgfbr2) was markedly upregulated in hepatocytes of the fibrotic liver. Tgfbr2 depletion in hepatocytes decreased the expressions of profibrogenic markers (Col1a1 and Acta2) in the CCl4 -treated fibrotic liver. RNA-seq analysis revealed that Tgfbr2 deletion in hepatocytes significantly reduced the inflammatory response and suppressed epithelial-mesenchymal transition of hepatocytes accompanied by upregulation of the metabolic pathways during liver fibrosis. Moreover, the expressions of hepatocyte nuclear factors (HNFs), including Hnf4α, Foxa1, Foxa2, and Foxa3, which are important for maintaining liver metabolism and homeostasis, were decreased in fibrotic livers and significantly increased after Tgfbr2 blockade. CONCLUSION: Blocking the TGF-ß signaling pathway in hepatocytes reduces hepatic fibrosis and improves hepatic function in fibrotic livers.

Sulodexide attenuates liver fibrosis in mice by restoration of differentiated liver sinusoidal endothelial cell.

Sulodexide is a heparinoid compound with wide-ranging pharmacological activities. However, the effect of sulodexide on liver fibrogenesis has not been reported. In this study, we aim to evaluate the therapeutic potential of sulodexide in mouse model of liver fibrosis and explore the underlying antifibrotic mechanisms. We found that sulodexide treatment significantly attenuated thioacetamide (TAA) and 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC)-induced liver fibrosis in mice. Transcriptome analysis revealed that sulodexide treatment downregulated fibrosis-related genes and liver sinusoidal endothelial cells (LSECs) capillarization-associated genes in fibrotic livers. Immunohistochemistry confirmed that the increased expression of LSEC capillarization-related genes (CD34, CD31 and Laminin) in liver fibrotic tissues was reduced by sulodexide treatment. Scanning electron microscopy showed that LSECs fenestrations were preserved upon sulodexide treatment. Quantitative real-time PCR and immunofluorescence demonstrated that the expression of mesenchymal markers was downregulated by sulodexide administration, suggesting sulodexide inhibited endothelial-mesenchymal transition of LSECs during liver fibrosis. Furthermore, sulodexide administration protected primary LSECs from endothelial dysfunction in vitro. In conclusion, sulodexide attenuated liver fibrosis in mice by restoration of differentiated LSECs, indicating that sulodexide treatment may present as a potential therapy for patients with liver fibrosis.

Novel therapeutics for portal hypertension and fibrosis in chronic liver disease.

Portal hypertension (PH) is the most common non-neoplastic complication of chronic liver disease, determining clinical complications that lead to death or liver transplantation. PH results from increased resistance to portal blood flow through the cirrhotic liver, which is due to hepatic fibrosis and microcirculatory dysfunction. The present review focuses on the pathophysiology of fibrosis and PH, describes currently used treatments, and critically discusses potential therapeutic options.

miR-541 potentiates the response of human hepatocellular carcinoma to sorafenib treatment by inhibiting autophagy.

OBJECTIVE: Autophagy participates in the progression of hepatocellular carcinoma (HCC) and the resistance of HCC cells to sorafenib. We investigated the feasibility of sensitising HCC cells to sorafenib by modulating miR-541-initiated microRNA-autophagy axis. DESIGN: Gain- and loss-of-function assays were performed to evaluate the effects of miR-541 on the malignant properties and autophagy of human HCC cells. Autophagy was quantified by western blotting of LC3, transmission electron microscopy analyses and confocal microscopy scanning of mRFP-GFP-LC3 reporter construct. Luciferase reporter assays were conducted to confirm the targets of miR-541. HCC xenograft tumours were established to analyse the role of miR-541 in sorafenib-induced lethality. RESULTS: The expression of miR-541 was downregulated in human HCC tissues and was associated with malignant clinicopathologic phenotypes, recurrence and survival of patients with HCC. miR-541 inhibited the growth, metastasis and autophagy of HCC cells both in vitro and in vivo. Prediction software and luciferase reporter assays identified autophagy-related gene 2A (ATG2A) and Ras-related protein Rab-1B (RAB1B) as the direct targets of miR-541. Consistent with the effects of the miR-541 mimic, inhibition of ATG2A or RAB1B suppressed the malignant phenotypes and autophagy of HCC cells. Furthermore, siATG2A and siRAB1B partially reversed the enhancement of the malignant properties and autophagy in HCC cells mediated by the miR-541 inhibitor. More interestingly, higher miR-541 expression predicted a better response to sorafenib treatment, and the combination of miR-541 and sorafenib further suppressed the growth of HCC cells in vivo compared with the single treatment. CONCLUSIONS: Dysregulation of miR-541-ATG2A/RAB1B axis plays a critical role in patients' responses to sorafenib treatment. Manipulation of this axis might benefit survival of patients with HCC, especially in the context of the highly pursued strategies to eliminate drug resistance.

Targeting PRMT5 Activity Inhibits the Malignancy of Hepatocellular Carcinoma by Promoting the Transcription of HNF4α.

Background: Liver cancer stem cells (LCSCs) are responsible for the initiation, progression and chemoresistance of liver cancer. However, no agent targeting LCSC is available in the clinic to date. Here, we investigated the effects of targeting protein arginine methyltransferase 5 (PRMT5), an epigenetic regulator, on LCSCs and HCC using a novel PRMT5 inhibitor DW14800. Methods: Tumor spheroid formation culture was used to enrich LCSCs and assess their self-renewal capability. Human alpha-1-antitrypsin (A1AT) ELISA, acetylated low-density lipoprotein (ac-LDL) uptake, periodic acid-Schiff (PAS) reactions and senescence associated ß-galactosidase (SA-ß-gal) activity assays were performed to examine the differentiation status of HCC cells. The effects of DW14800 on HCC malignancy were assessed in HCC cell lines and on an HCC xenograft model in mice. Chromatin immunoprecipitation was applied to clarify the transcriptional regulation of HNF4α by PRMT5-mediated Histone H4 arginine-3 symmetrical dimethylation (H4R3me2s). Results: Quantitative real-time PCR revealed that the expression of PRMT5 was upregulated in LCSCs. DW14800 specifically decreased the symmetrical dimethylation of arginine residues in HCC cells. Treatment of DW14800 suppressed the self-renewal capacity of LCSCs while re-establishing hepatocyte-specific characteristics in HCC cells. DW14800 displayed antitumor effects in HCC cells in vitro and in xenograft HCC in vivo. Importantly, ChIP assay showed that PRMT5 and H4R3me2s bound to the promoter region of HNF4α gene, and DW14800 increased the expression of HNF4α via reducing the H4R3me2s levels and enhancing the transcription of HNF4α. Conclusions: Our data revealed the significance of targeting PRMT5 activity in LCSC elimination and HCC differentiation, and proposed that DW14800 may represent a promising therapeutic agent for HCC in the clinic.

The transcription factor FOXA2 suppresses gastric tumorigenesis in vitro and in vivo.

BACKGROUND AND AIMS: The transcription factor forkhead box A2 (FOXA2) plays a central role in the development of endoderm-derived organs. It has been reported that FOXA2 acts as a suppressor in many kinds of tumor. However, little is known about the role of FOXA2 in gastric cancer. METHODS: The expression of FOXA2 in gastric cancer tissue samples from 89 patients was assessed by immunohistochemistry, and the clinicopathological characteristics of the samples were analyzed. The human gastric cancer cell line, BGC-823, was used to investigate the effects of FOXA2 in gastric cancer in vitro and in vivo and the potential mechanism involved was explored. RESULTS: FOXA2 expression in human gastric cancer cell lines and human gastric cancer tissues was lower compared with the normal gastric epithelium cell line GES1 and normal adult gastric tissues, respectively. Patients with high FOXA2 expression level had longer 5-year overall survival than those with low FOXA2 expression level. FOXA2 markedly inhibited growth of BGC-823 cells accompanied with the cell cycle arrest and apoptosis. Infection of BGC-823 cells by FOXA2 lentivirus resulted in reduced cell tumorigenesis in vitro and in vivo. Moreover, expression of Mucin 5AC was up-regulated along with increased expression of exogenous FOXA2 in BGC-823 cells; in contrast, dedifferentiation markers, BMI, CD54 and CD24, were down-regulated. CONCLUSIONS: These results suggest that FOXA2 induces the differentiation of gastric cancer and highlight FOXA2 as a novel therapeutic target and prognostic marker for human gastric cancer.

FOXA2 suppresses the metastasis of hepatocellular carcinoma partially through matrix metalloproteinase-9 inhibition.

The forkhead box transcription factor A2 (FOXA2) is a member of the hepatocyte nuclear factor family and plays an important role in liver development and metabolic homeostasis, but its role in the metastasis of hepatocellular carcinoma (HCC) has not been evaluated. In this study, we found that the expression of FOXA2 was decreased in 68.1% (49/72) of human HCC tissues compared with their paired non-cancerous adjacent tissues. Clinicopathological analysis revealed that reduced FOXA2 expression was correlated with aggressive characteristics (venous invasion, poor differentiation, high tumor node metastasis grade). FOXA2 level was even lower in portal vein tumor thrombus compared with primary tumor tissues and correlated with epithelial-mesenchymal transition in HCC cells. Overexpression of FOXA2 inhibited migration and invasion of Focus cells, whereas knockdown of FOXA2 in HepG2 showed the opposite effect. Moreover, upregulation of FOXA2 suppressed HCC metastasis to bone, brain and lung in two distinct mouse models. Finally, we proved that FOXA2 repressed the transcription of matrix metalloproteinase (MMP)-9 and exerted its antimetastasis effect partially through downregulation of MMP-9. In conclusion, our findings indicate that FOXA2 plays a critical role in HCC metastasis and may serve as a novel therapeutic target for HCC.

Gemcitabine in the chemoradiotherapy for locally advanced pancreatic cancer: a meta-analysis.

AIMS: Whether gemcitabine based chemoradiotherapy (GEM-based CRT) is superior to 5-fluorouracil based chemoradiotherapy (5-FU-based CRT) for locally advanced pancreatic cancer (LAPC) remains uncertain. The aim of the present study was to evaluate the effect of GEM-based CRT compared with 5-FU-based CRT. METHODS: Electronic database including Medline, Embase, Cochrane controlled trials register, PubMed (update to December 2010) and manual bibliography searches were carried out. A meta-analysis of all randomized clinical trials (RCTs) or other comparative studies comparing GEM-based CRT and 5-FU-based CRT were performed. RESULTS: Three RCTs and one retrospective comparative study including 229 patients were assessed. Meta-analysis showed survival advantage of GEM-based CRT compared with 5-FU-based CRT for 12-month (12-mo) survival rates (SRs) (RR=1.54, 95% CI 1.05-2.26, p=0.03). Moreover, there were also trends of benefit for SR after 6-months (RR 1.13, 95% CI 0.98-1.30, p=0.09) and 24-months (24-mo: RR 2.41, 95% CI 0.90-6.48, p=0.08), though the trends did not reach statistical significance. More frequent severe acute hematologic toxicities were found in the GEM-based CRT group. CONCLUSIONS: The meta-analysis found that GEM-based CRT was better than 5-FU-based CRT in the treatment of LAPC, especially for 12-mo SRs. However, the acute toxicity should be carefully regarded.