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The current understanding of cancer biology and development of effective treatments for cancer remain far from satisfactory. This in turn heavily relies on the availability of easy and robust model systems that resemble the architecture/physiology of the tumors in patients to facilitate research. Cancer research in vitro has mainly been based on the use of immortalized 2D cancer cell lines that deviate in many aspects from the original primary tumors. The recent development of the organoid technology allowing generation of organ-buds in 3D culture from adult stem cells has endowed the possibility of establishing stable culture from primary tumors. Although culturing organoids from liver tumors is thought to be difficult, we now convincingly demonstrate the establishment of organoids from mouse primary liver tumors. We have succeeded in culturing 91 lines from 129 liver tissue/tumors. These organoids can be grown in long-term cultures in vitro. About 20% of these organoids form tumors in immunodeficient mice upon (serial) transplantation, confirming their tumorigenic and self-renewal properties. Interestingly, single cells from the tumor organoids have high efficiency of organoid initiation, and a single organoid derived from a cancer cell is able to initiate a tumor in mice, indicating the enrichment of tumor-initiating cells in the tumor organoids. Furthermore, these organoids recapitulate, to some extent, the heterogeneity of liver cancer in patients, with respect to phenotype, cancer cell composition and treatment response. These model systems shall provide enormous opportunities to advance our research on liver cancer (stem cell) biology, drug development and personalized medicine. [ABSTRACT FROM AUTHOR]

CCAAT/enhancer-binding protein delta (CEBPD) is associated with the regulation of apoptosis and cell proliferation and is a candidate tumor suppressor gene. Here, we investigated its role in hepatocellular carcinoma (HCC). We observe that CEBPD mRNA expression is significantly downregulated in HCC tumors as compared with adjacent tissues. Protein levels of CEBPD are also lower in tumors relative to adjacent tissues. Reduced expression of CEBPD in the tumor correlates with worse clinical outcome. In both Huh7 and HepG2 cells, shRNA-mediated CEBPD knockdown significantly reduces cell proliferation, single cell colony formation and arrests cells in the G0/G1 phase. Subcutaneous xenografting of Huh7 in nude mice show that CEBPD knockdown results in smaller tumors. Gene expression analysis shows that CEBPD modulates interleukin-1 signaling. We conclude that CEBPD expression uncouples cancer compartment expansion and clinical outcome in HCC, potentially by modulating interleukin-1 signaling. Thus, although our results support the notion that CEBPD acts as a tumor suppressor in HCC, its action does not involve impairing compartment expansion per se but more likely acts through improving anticancer immunity. [ABSTRACT FROM AUTHOR]

Vascular endothelial growth factor (VEGF) is a key regulator of pathological angiogenesis and vascular permeability and overexpressed by most solid tumors. VEGF receptor-2 (VEGFR-2 or kinase-insert domain-containing receptor as it is called in human, KDR) is a specific receptor of VEGF with a high binding affinity. A solube recombinant extracellular domain 1-3 of human VEGFR-2 (rKDR1-3) was expressed in Escherichia coli (E. Coli) and purified from the bacterial periplasmic extracts by immobilized metal affinity chromatography and anion exchange chromatography to inhibit the VEGF-induced angiogenesis. A surface plasmon resonance (SPR) technology was adopted to analyze the affinity and kinetics constant between rKDR1-3 and VEGF165. Under the given experimental conditions, the association rate constant Ka was 1.06×105 M−1 S−1, the dissociation rate Kd was 6.09×10−3 S−1, the dissociation constant KD was 5.74×10−8 M. The effect of rKDR1-3 on VEGF-induced endothelial cell proliferation was studied using MTT assay, scratch-wound healing assay and chorioallantoic membrane (CAM) assay. The results showed that rKDR1-3 could inhibit neovascularization and serve as a useful drug candidate in research, diagnostics and therapy of cancer. [ABSTRACT FROM AUTHOR]

Highlights: [•] Provided a methodological study on the expression of a soluble recombinant membrane receptor portion in prokaryotic system. [•] Evaluated the anti-angiogenesis effect of VEGFR2 D3. [•] Provided a novel antiangiogenic blocker relating to VEGF/VEGFR2 pathway. [Copyright &y& Elsevier]

Background: The Pregnane X Receptor (PXR) is a principal signal transducer in mucosal responses to xenobiotic stress. It is well-recognized that inflammatory bowel disease is accompanied by xenobiotic stress, but the importance of the PXR in limiting inflammatory responses in inflammatory bowel disease remains obscure at best. Methods: We stimulate a total of 106 colonic biopsies from 19 Crohn’s disease patients with active disease, 36 colonic biopsies from 8 control patients, colonic organoids and various cell culture models (either proficient or genetically deficient with respect to PXR) in vitro with the PXR ligand rifampicin or vehicle. Effects on NF-κB activity are assessed by measuring interleukin-8 (IL-8) and interleukin-1ß (IL-1ß) mRNA levels by qPCR and in cell culture models by NF-κB reporter-driven luciferase activity and Western blot for signal transduction elements. Results: We observe a strict inverse correlation between colonic epithelial PXR levels and NF-κB target gene expression in colonic biopsies from Crohn’s disease patients. PXR, activated by rifampicin, is rate-limiting for mucosal NF-κB activation in IBD. The correlation between colonic epithelial PXR levels and NF-κB target gene expression was also observed in intestinal organoids system. Furthermore, in preclinical in vitro models of intestinal inflammation, including intestinal organoids, genetic inactivation of PXR unleashes NF-κB-dependent signal transduction whereas conversely NF-κB signaling reduces levels of PXR expression. Conclusions: Our data indicate that the PXR is a major and clinically relevant antagonist of NF-κB activity in the intestinal epithelial compartment during inflammatory bowel disease. [ABSTRACT FROM AUTHOR]

Background & Aims: In liver cancer, leucine‐rich repeat‐containing G‐protein coupled receptor 5 (LGR5) compartment represents an important tumor‐initiating cell (TIC) population and served as a potential therapeutic target. Cancer‐associated fibroblasts (CAFs) is a critical part of the tumor microenvironment, heavily influenced TIC function and fate. However, deeply investigations have been hindered by the lack of accurate preclinical models to investigate the interaction between CAFs and TIC. Organoids model have achieved major advancements as a precious research model for recapitulating the morphological aspects of organs, and thus also serving as a candidate model to investigate the mutual interaction between different cell types. Consequently, this study aimed to construct a three‐dimensional (3D) co‐culture organoid model of primary LGR5‐expressing tumor stem cells from primary murine liver tumors with CAFs to investigate the impact of CAFs on LGR5 marked TICs in liver cancer. Materials and Methods: First, both of the transgenic LGR5‐diphtheria toxin receptor (DTR)‐GFP knock‐in mice and transgenic Rosa26‐mT mice developed primary liver tumors by diethylnitrosamine (DEN) administration. Tumor organoids and CAFs were generated from those primary liver cancer separately. Second, LGR5‐expressing TICs organoid with CAFs were established ex vivo based on cell–cell contact or trans‐well co‐culture system, and the mutual influence between those two types of cells was further investigated. Subsequently, immunodeficient mouse‐based xenograft model was further adopted to evaluate the influence of CAFs to LGR5 tumor stem cell, tumor formation, and metastasis. Results: The co‐culture organoid model composed of murine liver tumor LGR5+ tumor‐initiating cells and CAFs in 3D co‐culture was successfully established, with the intention to investigate their mutual interaction. The existence of CAFs upon engrafting tumor organoids resulted in dramatic higher number of LGR5+ cells in the neoplasia when compared with engrafting tumor organoids alone. Furthermore, ex vivo culture of isolated LGR5+ cells from tumors of co‐engrafted mice formed significantly larger size of organoids than mono‐engrafted. Our results also indicated significantly larger size and number of formed organoids, when LGR5+ cells co‐cultured with CAF in both cell–cell contact and paracrine signaling in vitro, comparing to LGR5+ cells alone. Furthermore, we found that specific knockout of LGR5 expressing cells suppressed CAF‐mediated promotion of tumor formation, growth, and metastasis in the experimental mice model. Conclusions: Altogether, in a 3D co‐culture type of murine liver LGR5+ cells and cancer‐associated fibroblasts, we have demonstrated robust effects of CAFs in the promotion of LGR5 marked liver TICs. We also further revealed the influence of tumor microenvironment on stem cell‐related therapy, suggesting the possibility of combing CAF‐targeted and tumor stem cell targeted therapy in treating liver cancer. [ABSTRACT FROM AUTHOR]

We report a facile fabrication of carbon dots (CDs)/Cu 2 MoS 4 nanosheets hybrid photocathodes for potential application in photoelectrochemical cells (PECs). The structural, morphological and photoelectrochemical characteristics are studied. Compared with pristine Cu 2 MoS 4 , the photoelectrocatalytic activity of CDs/Cu 2 MoS 4 nanosheets composites was significantly improved under artificial solar light, as confirmed by the lowered onset potential and improved photocurrent response. Our study provides useful insights in the design of low-cost and earth abundant materials for high-efficiency solar fuel production. [ABSTRACT FROM AUTHOR]

Fatty liver disease has grown into a major global health burden, attributed to multi-factors including sedentary lifestyle, obesogenic diet and prevalence of metabolic disorders. The lack of robust experimental models is hampering the research and therapeutic development for fatty liver disease. This study aims to develop an organoid-based 3D culture model to recapitulate key features of fatty liver disease focusing on intracellular lipid accumulation and metabolic dysregulation. We used human liver-derived intrahepatic cholangiocyte organoids and hepatocyte differentiated organoids. These organoids were exposed to lactate, pyruvate, and octanoic acid (LPO) for inducing lipid accumulation and mitochondrial impairment. Lipid accumulation resulted in alternations of gene transcription with major effects on metabolic pathways, including triglyceride and glucose level increase, which is consistent with metabolic changes in fatty liver disease patients. Interestingly, lipid accumulation affected mitochondria as shown by morphological transitions, alternations in expression of mitochondrial encoded genes, and reduction of ATP production. Meanwhile, we found treatment with obeticholic acid and metformin can alleviate fat accumulation in organoids. This study demonstrated that LPO exposure can induce lipid accumulation and associated metabolic dysregulation in human liver-derived organoids. This provides an innovative model for studying fatty liver disease and testing potential therapeutics. Key messages: Lactate, pyruvate, and octanoic acid induce lipid accumulation in liver organoids. Organoids of human compared to mouse origin are more efficient in lipid accumulation. Lipid accumulation dysregulates metabolic pathway and impairs mitochondrial function. Demonstrating a proof-of-concept for testing medications in organoids. [ABSTRACT FROM AUTHOR]

Background and aims: Hepatitis E virus (HEV), as an emerging zoonotic pathogen, is a leading cause of acute viral hepatitis worldwide, with a high risk of developing chronic infection in immunocompromised patients. However, the global epidemiology of HEV infection has not been comprehensively assessed. This study aims to map the global prevalence and identify the risk factors of HEV infection by performing a systematic review and meta‐analysis. Methods: A systematic searching of articles published in Medline, Embase, Web of science, Cochrane and Google scholar databases till July 2019 was conducted to identify studies with HEV prevalence data. Pooled prevalence among different countries and continents was estimated. HEV IgG seroprevalence of subgroups was compared and risk factors for HEV infection were evaluated using odd ratios (OR). Results: We identified 419 related studies which comprised of 1 519 872 individuals. A total of 1 099 717 participants pooled from 287 studies of general population estimated a global anti‐HEV IgG seroprevalence of 12.47% (95% CI 10.42‐14.67; I2 = 100%). Notably, the use of ELISA kits from different manufacturers has a substantial impact on the global estimation of anti‐HEV IgG seroprevalence. The pooled estimate of anti‐HEV IgM seroprevalence based on 98 studies is 1.47% (95% CI 1.14‐1.85; I2 = 99%). The overall estimate of HEV viral RNA‐positive rate in general population is 0.20% (95% CI 0.15‐0.25; I2 = 98%). Consumption of raw meat (P =.0001), exposure to soil (P <.0001), blood transfusion (P =.0138), travelling to endemic areas (P =.0244), contacting with dogs (P =.0416), living in rural areas (P =.0349) and receiving education less than elementary school (P <.0001) were identified as risk factors for anti‐HEV IgG positivity. Conclusions: Globally, approximately 939 million corresponding to 1 in 8 individuals have ever experienced HEV infection. 15‐110 million individuals have recent or ongoing HEV infection. Our study highlights the substantial burden of HEV infection and calls for increasing routine screening and preventive measures. [ABSTRACT FROM AUTHOR]

Hedgehog proteins are pivotal morphogens acting through a canonical pathway involving first activation of ligand binding to Patched followed by alleviation of Smoothened receptor inhibition, leading to activation of Gli transcription factors. Noncanonical Hedgehog signaling remains poorly characterized but is thought to be mainly dependent on Smoothened. However, Smoothened inhibitors have yielded only partial success in combating Hedgehog signal transduction- dependent cancer, suggesting that noncanonical Smoothened-independent pathways also are clinically relevant. Moreover, several Smoothened-de- pendent effects (e.g. neurite projection) do not require transcriptional activation, further suggesting biological importance of noncanonical Smoothened-dependent pathways. We comprehensively characterized the cellular kinome in Hedgehog-challenged murine WT and Smoothened-/- fibroblasts as well as Smoothened agonist-stimulated cells. A peptide assay-based kinome analysis (in which cell lysates are used to phosphorylate specific kinase substrates), along with endocytosis, Lucifer Yellow-based, and immunoblotting assays, identified an elaborate signaling network of both Smoothened-dependent and -independent pathways that mediates actin reorganization through Src-like kinases, activates various proinflammatory signaling cascades, and concomitantly stimulates Wnt and Notch signaling while suppressing bone morphogenetic protein (BMP) signaling. The contribution of noncanonical Smoothened-inde- pendent signaling to the overall effects of Hedgehog on cellular physiology appears to be much larger than previously envisioned and may explain the transcriptionally independent effects of Hedgehog signaling on cytoskeleton. The observation that Patched-dependent, Smoothened-independent, noncanonical Hedgehog signaling increases Wnt/Notch signaling provides a possible explanation for the failure of Smoothened antagonists in combating Hedgehog-dependent but Smoothened inhibitor-resistant cancer. Our findings suggest that inhibiting Hedgehog-Patched interaction could result in more effective therapies as compared with conventional Smoothened-directed therapies. [ABSTRACT FROM AUTHOR]

Abstract: Interferons (IFNs) with antiviral and immune-stimulatory functions have been widely used in prevention and treatment of hepatocellular carcinoma (HCC). Signal transducer and activator of transcription 1 (STAT1) is a key element of the IFN signaling, and the function of STAT1 is critically determined by its phosphorylation state. This study aims to understand the functions of phosphorylated (p-) and unphosphorylated (u-) STAT1 in HCC. We found that u-STAT1 is significantly elevated in patient HCC tumor tissues and predominantly expressed in cytoplasm; while p-STAT1 is absent. Loss of u-STAT1 potently arrested cell cycle and inhibited cell growth in HCC cells. Induction of p-STAT1 by IFN-α treatment effectively triggers the expression of interferon-stimulated genes (ISGs), but has moderate effect on HCC cell growth. Interestingly, both u-STAT1 and p-STAT1 are induced by IFN-α, through with distinct time-dependent process. Furthermore, the ISG induction patterns mediated by p-STAT1 and u-STAT1 are also distinct. Importantly, artificial blocking of the induction of u-STAT1, but not p-STAT1, sensitizes HCC cells to treatment of IFNs. Therefore, p-STAT1 and u-STAT1 exert dichotomal functions and coordinately regulate the responsiveness to IFN treatment in HCC.Key Messages: STAT1 is upregulated and predominantly presented as u-STAT1 in HCC, while p-STAT1 is absent.U-STAT1 sustains but p-STAT1 inhibits HCC growth.The dynamic change of phosphorylation state of STAT1 control the responsiveness to IFN treatment. [ABSTRACT FROM AUTHOR]

Rotavirus infection is a major cause of severe dehydrating diarrhea in infants younger than 5 y old and in particular cases of immunocompromised patients irrespective to the age of the patients. Although vaccines have been developed, antiviral therapy is an important complement that cannot be substituted. Because of the lack of specific approved treatment, it is urgent to facilitate the cascade of further understanding of the infection biology, identification of druggable targets and the final development of effective antiviral therapies. PI3K-Akt-mTOR signaling pathway plays a vital role in regulating the infection course of many viruses. In this study, we have dissected the effects of PI3K-Akt-mTOR signaling pathway on rotavirus infection using both conventional cell culture models and a 3D model of human primary intestinal organoids. We found that PI3K-Akt-mTOR signaling is essential in sustaining rotavirus infection. Thus, blocking the key elements of this pathway, including PI3K, mTOR and 4E-BP1, has resulted in potent anti-rotavirus activity. Importantly, a clinically used mTOR inhibitor, rapamycin, potently inhibited both experimental and patient-derived rotavirus strains. This effect involves 4E-BP1 mediated induction of autophagy, which in turn exerts anti-rotavirus effects. These results revealed new insights on rotavirus-host interactions and provided new avenues for antiviral drug development. [ABSTRACT FROM AUTHOR]

In this study, flower-like Bi2MoO6/BiOI heterostructure photocatalysts were synthesized via an anion exchange method using BiOI as precursor. The composition of Bi2MoO6/BiOI can be easily controlled by adjusting the MoO/I molar ratio. Photocatalytic activity studies based on the degradation of Rhodamine B (RhB) show that Bi2MoO6/BiOI50% photocatalyst exhibited the best performance under visible light excitation. The radical scavengers test demonstrated that holes was the main reactive species for the degradation of RhB, andO also took part in the photodecomposition process. Photoelectrochemical measurement reveals that the Bi2MoO6/BiOI50% exhibit enhanced carrier densities, charge separation and photocurrent compared with the original Bi2MoO6 and BiOI. Our results show that bismuth-based heterojunctions fabricated through the anion exchange method could be a cost-effective approach to improve the photocatalytic activity and photoelectrochemical performance of BiOI. Flower-like Bi2MoO6/BiOI heterostructures were synthesized via an anion exchange method. The photocatalytic test confirmed that the activity of Bi2MoO6/BiOI heterojunctions is greatly improved by degrading RhB solution under visible light irradiation, and Bi2MoO6/BiOI=50% photocatalyst exhibited best photocatalytic activity and photoelectrochemical performance. [ABSTRACT FROM AUTHOR]

• Lipid droplets exert a variety of key biological functions. • Lipid droplets actively interact with other organelles. • Lipid droplets play key roles in health and disease of the liver. • The biological functions of lipid droplet-organelle interactions remain obscure. Lipid droplets are cellular organelles used for lipid storage with a hydrophobic core of neutral lipids enclosed by a phospholipid monolayer. Besides presenting as giant single organelles in fat tissue, lipid droplets are also widely present as a multitude of small structures in hepatocytes, where they play key roles in health and disease of the liver. In addition to lipid storage, lipid droplets are also directly involved in lipid metabolism, membrane biosynthesis, cell signaling, inflammation, pathogen-host interaction and cancer development. In addition, they interact with other cellular organelles to regulate cellular biology. It is fair to say that the exact functions of lipid droplets in cellular physiology remain largely obscure. Thus prompted, here we aim to analyze the corpus of contemporary biomedical literature to create a framework as to how the role of lipid droplets in hepatocyte physiology and pathophysiology should be understood. The resulting framework should help understanding the interaction of lipid droplets with other organelles in important liver diseases, including fatty liver disease, viral hepatitis and liver cancer and direct further research directions. [ABSTRACT FROM AUTHOR]

Background: Comprehensive evaluation of safety and efficacy of different combinations of direct‐acting antivirals (DAAs) in liver transplant recipients with genotype 1 (GT1) hepatitis C virus (HCV) recurrence remains limited. Therefore, we performed this systematic review and meta‐analysis in order to evaluate the clinical outcome of DAA treatment in liver transplant patients with HCV GT1 recurrence. Methods: Studies were included if they contained information of 12 weeks sustained virologic response (SVR12) after DAA treatment completion as well as treatment related complications for liver transplant recipients with GT1 HCV recurrence. Results: We identified 16 studies comprising 885 patients. The overall pooled estimate proportion of SVR12 was 93% (95% confidence interval (CI): 0.89, 0.96), with moderate heterogeneity observed (τ2 = 0.01, P < 0.01, I2=75%). High tolerability was observed in liver transplant recipients reflected by serious adverse events (sAEs) with pooled estimate proportion of 4% (95% CI: 0.01, 0.07; τ2 = 0.02, P < 0.01, I2 = 81%). For subgroup analysis, a total of five different DAA regimens were applied for treating these patients. Sofosbuvir/Ledipasvir (SOF/LDV) led the highest pooled estimate SVR12 proportion, followed by Paritaprevir/Ritonavir/Ombitasivir/Dasabuvir (PrOD), Daclatasvir (DCV)/Simeprevir (SMV) ± Ribavirin (RBV), and SOF/SMV ± RBV, Asunaprevir (ASV)/DCV. There was a tendency for favoring a higher pooled SVR12 proportion in patients with METAVIR Stage F0‐F2 of 97% (95% CI: 0.93, 0.99) compared to 85% (95% CI: 0.79, 0.90) for stage F3‐F4 (P < 0.01). There was no significant difference between LT recipients treated with or without RBV (P = 0.23). Conclusions: Direct‐acting antiviral treatment is highly effective and well‐tolerated in liver transplant recipients with recurrent GT1 HCV infection. [ABSTRACT FROM AUTHOR]