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1.
Adv Sci (Weinh) ; 11(18): e2309984, 2024 May.
Article in English | MEDLINE | ID: mdl-38430531

ABSTRACT

The induction of cuproptosis, a recently identified form of copper-dependent immunogenic cell death, is a promising approach for antitumor therapy. However, sufficient accumulation of intracellular copper ions (Cu2+) in tumor cells is essential for inducing cuproptosis. Herein, an intelligent cuproptosis-inducing nanosystem is constructed by encapsulating copper oxide (CuO) nanoparticles with the copper ionophore elesclomol (ES). After uptake by tumor cells, ES@CuO is degraded to release Cu2+ and ES to synergistically trigger cuproptosis, thereby significantly inhibiting the tumor growth of murine B16 melanoma cells. Moreover, ES@CuO further promoted cuproptosis-mediated immune responses and reprogrammed the immunosuppressive tumor microenvironment by increasing the number of tumor-infiltrating lymphocytes and secreted inflammatory cytokines. Additionally, combining ES@CuO with programmed cell death-1 (PD-1) immunotherapy substantially increased the antitumor efficacy in murine melanoma. Overall, the findings of this study can lead to the use of a novel strategy for cuproptosis-mediated antitumor therapy, which may enhance the efficacy of immune checkpoint inhibitor therapy.


Subject(s)
Copper , Immunotherapy , Melanoma, Experimental , Animals , Mice , Immunotherapy/methods , Copper/chemistry , Melanoma, Experimental/drug therapy , Melanoma, Experimental/immunology , Disease Models, Animal , Tumor Microenvironment/drug effects , Tumor Microenvironment/immunology , Mice, Inbred C57BL , Cell Line, Tumor , Chlorophyllides , Nanoparticles/chemistry
2.
Ann Surg Oncol ; 31(3): 1749-1759, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38112885

ABSTRACT

PURPOSE: We aimed to establish a machine learning radiomics liver function model to explore how liver function affects the prognosis of patients with gastric cancer (GC). METHODS: Patients with advanced GC were retrospectively enrolled in this study. Eight machine learning radiomic models were constructed by extracting radiomic features from portal-vein-phase contrast-enhanced computed tomography (CE-CT) images. Clinicopathological features were determined using univariate and multifactorial Cox regression analyses. These features were used to construct a GC survival nomogram. RESULTS: A total of 510 patients with GC were split into training and test cohorts in an 8:2 ratio. Kaplan-Meier analysis showed that patients with type I liver function had a better prognosis. Fifteen significant features were retained to establish the machine learning model. LightBGM showed the best predictive performance in the training (area under the receiver operating characteristic curve [AUC] 0.978) and test cohorts (AUC 0.714). Multivariate analysis revealed that gender, age, liver function, Nutritional Risk Screening 2002 (NRS-2002) score, tumor-lymph node-metastasis stage, tumor size, and tumor differentiation were independent risk factors for GC prognosis. The survival nomogram based on machine learning radiomics, instead of liver biochemical indicators, still had high accuracy (C-index of 0.771 vs. 0.773). CONCLUSION: The machine learning radiomics liver function model has high diagnostic value in predicting the influence of liver function on prognosis in patients with GC.


Subject(s)
Stomach Neoplasms , Humans , Prognosis , Retrospective Studies , Radiomics , Nomograms , Liver , Machine Learning
3.
BMC Bioinformatics ; 24(1): 444, 2023 Nov 23.
Article in English | MEDLINE | ID: mdl-37996806

ABSTRACT

For ligand binding prediction, it is crucial for molecular docking programs to integrate template-based modeling with a precise scoring function. Here, we proposed the CoDock-Ligand docking method that combines template-based modeling and the GNINA scoring function, a Convolutional Neural Network-based scoring function, for the ligand binding prediction in CASP15. Among the 21 targets, we obtained successful predictions in top 5 submissions for 14 targets and partially successful predictions for 4 targets. In particular, for the most complicated target, H1114, which contains 56 metal cofactors and small molecules, our docking method successfully predicted the binding of most ligands. Analysis of the failed systems showed that the predicted receptor protein presented conformational changes in the backbone and side chains of the binding site residues, which may cause large structural deviations in the ligand binding prediction. In summary, our hybrid docking scheme was efficiently adapted to the ligand binding prediction challenges in CASP15.


Subject(s)
Proteins , Proteins/chemistry , Molecular Docking Simulation , Protein Binding , Ligands , Binding Sites , Protein Conformation
4.
Proteins ; 91(12): 1658-1683, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37905971

ABSTRACT

We present the results for CAPRI Round 54, the 5th joint CASP-CAPRI protein assembly prediction challenge. The Round offered 37 targets, including 14 homodimers, 3 homo-trimers, 13 heterodimers including 3 antibody-antigen complexes, and 7 large assemblies. On average ~70 CASP and CAPRI predictor groups, including more than 20 automatics servers, submitted models for each target. A total of 21 941 models submitted by these groups and by 15 CAPRI scorer groups were evaluated using the CAPRI model quality measures and the DockQ score consolidating these measures. The prediction performance was quantified by a weighted score based on the number of models of acceptable quality or higher submitted by each group among their five best models. Results show substantial progress achieved across a significant fraction of the 60+ participating groups. High-quality models were produced for about 40% of the targets compared to 8% two years earlier. This remarkable improvement is due to the wide use of the AlphaFold2 and AlphaFold2-Multimer software and the confidence metrics they provide. Notably, expanded sampling of candidate solutions by manipulating these deep learning inference engines, enriching multiple sequence alignments, or integration of advanced modeling tools, enabled top performing groups to exceed the performance of a standard AlphaFold2-Multimer version used as a yard stick. This notwithstanding, performance remained poor for complexes with antibodies and nanobodies, where evolutionary relationships between the binding partners are lacking, and for complexes featuring conformational flexibility, clearly indicating that the prediction of protein complexes remains a challenging problem.


Subject(s)
Algorithms , Protein Interaction Mapping , Protein Interaction Mapping/methods , Protein Conformation , Protein Binding , Molecular Docking Simulation , Computational Biology/methods , Software
5.
Nucleic Acids Res ; 51(W1): W365-W371, 2023 07 05.
Article in English | MEDLINE | ID: mdl-37194703

ABSTRACT

The rapid emergence of SARS-CoV-2 variants with multi-sites mutations is considered as a major obstacle for the development of drugs and vaccines. Although most of the functional proteins essential for SARS-CoV-2 have been determined, the understanding of the COVID-19 target-ligand interactions remains a key challenge. The old version of this COVID-19 docking server was built in 2020, and free and open to all users. Here, we present nCoVDock2, a new docking server to predict the binding modes for targets from SARS-CoV-2. First, the new server supports more targets. We replaced the modeled structures with newly resolved structures and added more potential targets of COVID-19, especially for the variants. Second, for small molecule docking, Autodock Vina was upgraded to the latest version 1.2.0, and a new scoring function was added for peptide or antibody docking. Third, the input interface and molecular visualization were updated for a better user experience. The web server, together with an extensive help and tutorial, are freely available at: https://ncovdock2.schanglab.org.cn.


Subject(s)
COVID-19 , SARS-CoV-2 , Software , Humans , Ligands , Molecular Docking Simulation , SARS-CoV-2/genetics , Peptides , Antibodies , Internet
6.
Cancer Res ; 82(23): 4400-4413, 2022 12 02.
Article in English | MEDLINE | ID: mdl-36197797

ABSTRACT

Lysyl oxidase-like 2 (LOXL2) is a member of the scavenger receptor cysteine-rich (SRCR) repeat carrying LOX family. Although LOXL2 is suspected to be involved in histone association and chromatin modification, the role of LOXL2 in epigenetic regulation during tumorigenesis and cancer progression remains unclear. Here, we report that nuclear LOXL2 associates with histone H3 and catalyzes H3K36ac deacetylation and deacetylimination. Both the N-terminal SRCR repeats and the C-terminal catalytic domain of LOXL2 carry redundant deacetylase catalytic activity. Overexpression of LOXL2 markedly reduced H3K36 acetylation and blocked H3K36ac-dependent transcription of genes, including c-MYC, CCND1, HIF1A, and CD44. Consequently, LOXL2 overexpression reduced cancer cell proliferation in vitro and inhibited xenograft tumor growth in vivo. In contrast, LOXL2 deficiency resulted in increased H3K36 acetylation and aberrant expression of H3K36ac-dependent genes involved in multiple oncogenic signaling pathways. Female LOXL2-deficient mice spontaneously developed uterine hypertrophy and uterine carcinoma. Moreover, silencing LOXL2 in cancer cells enhanced tumor progression and reduced the efficacy of cisplatin and anti-programmed cell death 1 (PD-1) combination therapy. Clinically, low nuclear LOXL2 expression and high H3K36ac levels corresponded to poor prognosis in uterine endometrial carcinoma patients. These results suggest that nuclear LOXL2 restricts cancer development in the female reproductive system via the regulation of H3K36ac deacetylation. SIGNIFICANCE: LOXL2 loss reprograms the epigenetic landscape to promote uterine cancer initiation and progression and repress the efficacy of anti-PD-1 immunotherapy, indicating that LOXL2 is a tumor suppressor.


Subject(s)
Amino Acid Oxidoreductases , Epigenesis, Genetic , Humans , Mice , Female , Animals , Amino Acid Oxidoreductases/genetics , Amino Acid Oxidoreductases/metabolism , Acetylation , Histones/metabolism , Hypertrophy/genetics , Gene Expression
7.
Comput Math Methods Med ; 2021: 7596343, 2021.
Article in English | MEDLINE | ID: mdl-34899969

ABSTRACT

BACKGROUND: N-Acetylcysteine (NAC) had exerted antioxidation and anti-inflammation effects on chronic obstructive pulmonary disease (COPD) patients. However, its effect in regulating interleukin- (IL-) 18 was not fully understood. This study was designed to evaluate the specific mechanism of NAC regulating IL-18. MATERIALS AND METHODS: A total of 112 COPD patients and 103 health individuals were recruited in the study. Cytokine level in patients' serum was measured by enzyme-linked immunosorbent assay (ELISA). A COPD mouse model was established by administration of lipopolysaccharide (LPS) and cigarette smoke. The expression of cytokines was measured by ELISA and flow cytometry. Inflammasome-related protein was measured by Western blot. RESULT: NAC could effectively improve the immune status of COPD patients as well as the COPD mouse model by downregulating proinflammation and inflammation cytokines including IL-1ß, interferon- (IFN-) γ, tumor necrosis factor- (TNF-) α, and IL-18. It also had the capability to suppress synthesis of IL-18 in macrophage to inhibit the secretion of IFN-γ from natural killer (NK) cells through influencing the inflammasome-related protein in macrophages. CONCLUSION: NAC could effectively inhibit the production of IL-18 by suppressing NLRP3 expression in macrophages to reduce the production of IFN-γ in NK cells.


Subject(s)
Acetylcysteine/pharmacology , Interferon-gamma/biosynthesis , Interleukin-18/biosynthesis , Killer Cells, Natural/drug effects , Killer Cells, Natural/immunology , NLR Family, Pyrin Domain-Containing 3 Protein/antagonists & inhibitors , Pulmonary Disease, Chronic Obstructive/drug therapy , Pulmonary Disease, Chronic Obstructive/immunology , Aged , Animals , Case-Control Studies , Computational Biology , Cytokines/blood , Disease Models, Animal , Female , Humans , Interleukin-18/antagonists & inhibitors , Lung/drug effects , Lung/immunology , Lung/pathology , Macrophages/drug effects , Macrophages/immunology , Male , Mice , Mice, Inbred C57BL , Middle Aged , Pulmonary Disease, Chronic Obstructive/pathology
8.
Proteins ; 89(12): 1800-1823, 2021 12.
Article in English | MEDLINE | ID: mdl-34453465

ABSTRACT

We present the results for CAPRI Round 50, the fourth joint CASP-CAPRI protein assembly prediction challenge. The Round comprised a total of twelve targets, including six dimers, three trimers, and three higher-order oligomers. Four of these were easy targets, for which good structural templates were available either for the full assembly, or for the main interfaces (of the higher-order oligomers). Eight were difficult targets for which only distantly related templates were found for the individual subunits. Twenty-five CAPRI groups including eight automatic servers submitted ~1250 models per target. Twenty groups including six servers participated in the CAPRI scoring challenge submitted ~190 models per target. The accuracy of the predicted models was evaluated using the classical CAPRI criteria. The prediction performance was measured by a weighted scoring scheme that takes into account the number of models of acceptable quality or higher submitted by each group as part of their five top-ranking models. Compared to the previous CASP-CAPRI challenge, top performing groups submitted such models for a larger fraction (70-75%) of the targets in this Round, but fewer of these models were of high accuracy. Scorer groups achieved stronger performance with more groups submitting correct models for 70-80% of the targets or achieving high accuracy predictions. Servers performed less well in general, except for the MDOCKPP and LZERD servers, who performed on par with human groups. In addition to these results, major advances in methodology are discussed, providing an informative overview of where the prediction of protein assemblies currently stands.


Subject(s)
Computational Biology/methods , Models, Molecular , Proteins , Software , Binding Sites , Molecular Docking Simulation , Protein Interaction Domains and Motifs , Proteins/chemistry , Proteins/metabolism , Sequence Analysis, Protein
9.
Bioprocess Biosyst Eng ; 43(10): 1869-1883, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32447514

ABSTRACT

To enhance specific or total sophorolipids (SLs) production by Starmerella bombicola for specific application, mutant library consisting of 106 mutants from 7 batches was constructed via atmospheric and room-temperature plasma (ARTP). When compared to the wild strain, 11, 36 and 12 mutants performed increases over 30% in lactonic, acidic or total SLs production. Genetic stability investigation showed that 8, 7, and 4 mutants could maintain the improved SLs production capacity. Mutants of A6-9 and A2-8 were selected out for enhanced specific SLs and total SLs production in fed-batch cultivation in flask. Without optimization, A6-9 obtained the highest reported lactonic SLs production of 51.95 g/l and A2-8 performed comparable acidic and total SLs production of 68.75 g/l and 100.33 g/l with all the reported stains. The structural composition of the obtained SLs was analyzed by HPLC and LC/MS, and the results confirmed the enhancement of SLs and certain SL components. These mutants would be important in industrial applications because the production and purification costs of SLs could be greatly reduced. Besides, the acquisition of these mutants also provided materials for the investigation of regulation mechanism of SLs biosynthesis for further genetic engineering of S. bombicola. Furthermore, critical micelle concentration (CMC), minimum surface tension (STmin) and hydrophilic-lipophilic balance (HLB) of the SLs obtained from the wild and mutant strains were also examined and compared. These results demonstrated the feasibility of obtaining SLs with different properties from different strains and the high efficiency of mutation breeding of S. bombicola by ARTP.


Subject(s)
Mutation , Oleic Acids/biosynthesis , Plasma Gases/pharmacology , Saccharomycetales , Oleic Acids/genetics , Saccharomycetales/genetics , Saccharomycetales/metabolism
10.
J Cell Mol Med ; 22(9): 4056-4067, 2018 09.
Article in English | MEDLINE | ID: mdl-29992739

ABSTRACT

Acute liver failure (ALF) is associated with high mortality, and a poor understanding of the underlying pathophysiology has resulted in a lack of effective treatments so far. Here, using an amatoxin-induced rhesus monkey model of ALF, we panoramically revealed the cellular and molecular events that lead to the development of ALF. The challenged monkeys with toxins underwent a typical course of ALF including severe hepatic injury, systemic inflammation and eventual death. Adaptive immune was not noticeably disturbed throughout the progress of ALF. A systematic examination of serum factors and cytokines revealed that IL-6 increase was the most rapid and drastic. Interestingly, we found that IL-6 was mainly produced by circulating monocytes. Furthermore, ablation of monocyte-derived IL-6 in mice decreased liver injury and systemic inflammation following chemical injection. Our findings reveal a critical role of circulating monocytes in initiating and accelerating ALF, indicating a potential therapeutic target in clinical treatment for ALF.


Subject(s)
Amanitins/toxicity , Hepatic Encephalopathy/immunology , Interleukin-6/immunology , Lipopolysaccharides/toxicity , Liver Failure, Acute/immunology , Monocytes/immunology , Alanine Transaminase/blood , Animals , Aspartate Aminotransferases/blood , Cytokines/genetics , Cytokines/immunology , Disease Progression , Gene Expression , Hepatic Encephalopathy/chemically induced , Hepatic Encephalopathy/genetics , Hepatic Encephalopathy/pathology , Interleukin-6/deficiency , Interleukin-6/genetics , L-Lactate Dehydrogenase/blood , Liver Failure, Acute/chemically induced , Liver Failure, Acute/genetics , Liver Failure, Acute/pathology , Liver Function Tests , Macaca mulatta , Mice , Monocytes/pathology
11.
Cell Death Dis ; 9(3): 398, 2018 03 14.
Article in English | MEDLINE | ID: mdl-29540666

ABSTRACT

Histone deacetylase 3 (HDAC3) plays pivotal roles in cell cycle regulation and is often aberrantly expressed in various cancers including hepatocellular carcinoma (HCC), but little is known about its role in liver regeneration and liver cancer cells proliferation. Using an inducible hepatocyte-selective HDAC3 knockout mouse, we find that lack of HDAC3 dramatically impaired liver regeneration and blocked hepatocyte proliferation in the G1 phase entry. HDAC3 inactivation robustly disrupted the signal transducer and activator of transcription 3 (STAT3) cascade. HDAC3 silencing impaired the ac-STAT3-to-p-STAT3 transition in the cytoplasm, leading to the subsequent breakdown of STAT3 signaling. Furthermore, overexpressed HDAC3 was further associated with increased tumor growth and a poor prognosis in HCC patients. Inhibition of HDAC3 expression reduced liver cancer cells growth and inhibited xenograft tumor growth. Our results suggest that HDAC3 is an important regulator of STAT3-dependent cell proliferation in liver regeneration and cancer. These findings provide novel insights into the HDAC3-STAT3 pathway in liver pathophysiological processes.


Subject(s)
Histone Deacetylases/metabolism , Liver Neoplasms/metabolism , Liver Neoplasms/physiopathology , STAT3 Transcription Factor/metabolism , Animals , Cell Proliferation , Hepatocytes/cytology , Hepatocytes/metabolism , Histone Deacetylases/genetics , Humans , Liver Neoplasms/genetics , Liver Regeneration , Male , Mice , Mice, Knockout , STAT3 Transcription Factor/genetics , Signal Transduction
12.
Hepatobiliary Pancreat Dis Int ; 16(6): 638-644, 2017 Dec 15.
Article in English | MEDLINE | ID: mdl-29291784

ABSTRACT

BACKGROUND: The stimulatory G protein a subunit (Gsα) plays important roles in diverse cell processes including tumorigenesis. Activating mutations in Gsα gene (GNAS) have been reported to be associated with poor prognosis in various human carcinomas. Furthermore, Gsα signaling is crucial in promoting liver regeneration by interacting with growth factor signaling, indicating that Gsα might play a promoting role in cancer development. However, little is known about the correlation between Gsα levels and clinicopathological parameters in intrahepatic cholangiocarcinoma (ICC). METHODS: We performed immunoblotting to examine the expression levels of Gsα and Ki67 proteins in tumor tissues and the corresponding adjacent tissues. A total of 74 pair of specimens resected from 74 ICC patients were examined. The association between Gsα levels and clinicopathological findings and prognosis of the patients was evaluated. RESULTS: Western blotting demonstrated that the expression of Gsα was significantly higher in ICC tissues compared with that in their corresponding adjacent tissues. Gsα protein was highly expressed in about half of ICC tissues (48.6%, 36/74) while only 28.4% (21/74) of tumor adjacent tissues showed Gsα high expression (P=0.011). High Gsα expression in ICC was significantly associated with the numbers of tumor nodules (P=0.037) and lymph node metastases (P=0.010). Moreover, the level of Gsα was significantly and positively correlated with Ki67 expression (P<0.001). In addition, the recurrence-free survival rate and overall survival rate in the Gsα high group were significantly lower than those in the Gsα low group (P=0.004 and P=0.005, respectively). CONCLUSIONS: High Gsα expression is correlated with poor prognosis in ICC patients. Gsα might serve as a potential prognostic indicator of ICC.


Subject(s)
Bile Duct Neoplasms/chemistry , Biomarkers, Tumor/analysis , Cholangiocarcinoma/chemistry , Chromogranins/analysis , GTP-Binding Protein alpha Subunits, Gs/analysis , Bile Duct Neoplasms/mortality , Bile Duct Neoplasms/pathology , Bile Duct Neoplasms/surgery , Blotting, Western , Cholangiocarcinoma/mortality , Cholangiocarcinoma/secondary , Cholangiocarcinoma/surgery , Disease Progression , Disease-Free Survival , Female , Humans , Immunohistochemistry , Kaplan-Meier Estimate , Ki-67 Antigen/analysis , Lymphatic Metastasis , Male , Middle Aged , Neoplasm Staging , Proportional Hazards Models , Risk Factors , Time Factors , Treatment Outcome , Up-Regulation
13.
J Cell Mol Med ; 20(5): 939-48, 2016 May.
Article in English | MEDLINE | ID: mdl-26781774

ABSTRACT

As one of the most important post-transcriptional regulators, microRNAs (miRNAs) participate in diverse biological processes, including the regulation of cell proliferation. MiR-17~92 has been found to act as an oncogene, and it is closely associated with cell proliferation. However, its role in liver regeneration is still unclear. We generated a hepatocyte-specific miR-17~92-deficient mouse and used a mouse model with 70% partial hepatectomy (PH) or intraperitoneal injection of carbon tetrachloride to demonstrate the role of MiR-17~92 in liver regeneration. In quiescent livers, the expression of the miR-17~92 cluster showed a gender disparity, with much higher expression in female mice. The expression of four members of this cluster was found to be markedly reduced after 70% PH. The ablation of miR-17~92 led to obvious regeneration impairment during the early-stage regeneration in the female mice. Ovariectomy greatly reduced miR-17~92 expression but significantly promoted liver regeneration in wild-type mice. In addition, early regeneration impairment in miR-17~92-deficient livers could be largely restored following ovariectomy. The proliferation suppressors p21 and Pten were found to be the target effectors of miR-17~92. MiR-17~92 disruption resulted in elevated protein levels of p21 and Pten in regenerating livers. MiR-17~92 functions as a proliferation stimulator and acts in an oestrogen-dependent manner. The loss of this miRNA results in increases in p21 and Pten expression and therefore impairs liver regeneration in female mice.


Subject(s)
Chemical and Drug Induced Liver Injury/genetics , Cyclin-Dependent Kinase Inhibitor p21/genetics , Estrogens/metabolism , Hepatocytes/metabolism , Liver/metabolism , MicroRNAs/genetics , PTEN Phosphohydrolase/genetics , Animals , Carbon Tetrachloride , Cell Proliferation , Chemical and Drug Induced Liver Injury/metabolism , Chemical and Drug Induced Liver Injury/pathology , Cyclin-Dependent Kinase Inhibitor p21/metabolism , Female , Gene Expression Regulation , Hepatectomy , Hepatocytes/cytology , Liver/injuries , Liver/pathology , Liver Regeneration , Male , Mice , Mice, Knockout , MicroRNAs/metabolism , Ovariectomy , PTEN Phosphohydrolase/metabolism , Sex Factors , Signal Transduction
14.
J Hepatol ; 64(2): 342-351, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26386161

ABSTRACT

BACKGROUND & AIMS: The stimulatory G protein α subunit (Gsα) activates the cAMP-dependent pathway by stimulating the production of cAMP and participates in diverse cell processes. Aberrant expression of Gsα results in various pathophysiological disorders, including tumorigenesis, but little is known about its role in liver regeneration. METHODS: We generated a hepatocyte-specific Gsα gene knockout mouse to demonstrate the essential role of Gsα in liver regeneration using a mouse model with 70% partial hepatectomy (PH) or an intraperitoneal injection of carbon tetrachloride (CCl4). RESULTS: Gsα inactivation dramatically impaired liver regeneration and blocked proliferating hepatocytes in G1/S transition due to the simultaneous depression of cyclin-dependent kinase 2 (CDK2) and cyclin E1. Loss of Gsα led to a fundamental alteration in gene profiles. Among the altered signaling cascades, the MAPK/Erk pathway, which is downstream of growth factor signaling, was disrupted secondary to a defect in phosphorylated Raf1 (pRaf1), resulting in a deficiency in phosphorylated CREB (pCREB) and CDK2 ablation. The lack of pRaf1 also resulted in a failure to phosphorylate retinoblastoma, which releases and activates E2F1, and a decrease in cyclin E1. Although these factors could be phosphorylated through both Gsα and growth factor signaling, the unique function of Raf1 in the growth factor cascade collapsed in response to the lack of Gsα. CONCLUSION: The growth factor signaling pathway that promotes hepatocyte proliferation is dependent on Gsα signaling. Loss of Gsα leads to a breakdown of the crosstalk between cAMP and growth factor signaling and dramatically impairs liver regeneration.


Subject(s)
Cyclic AMP/metabolism , GTP-Binding Protein alpha Subunits, Gs , Hepatocytes/metabolism , Intercellular Signaling Peptides and Proteins/metabolism , Liver Regeneration/physiology , Animals , Cell Proliferation/physiology , Cyclin-Dependent Kinase 2/metabolism , GTP-Binding Protein alpha Subunits, Gs/genetics , GTP-Binding Protein alpha Subunits, Gs/metabolism , Genes, cdc/physiology , Humans , MAP Kinase Signaling System/physiology , Mice , Mice, Knockout , Signal Transduction/physiology
15.
Liver Int ; 36(2): 212-22, 2016 Feb.
Article in English | MEDLINE | ID: mdl-25944273

ABSTRACT

BACKGROUND & AIMS: Insufficient liver regeneration and hepatocyte injury caused by excessive portal perfusion are considered to be responsible for post-hepatectomy liver failure (PLF) or small-for-size syndrome in living-donor liver transplantation. Somatostatin can decrease portal vein pressure (PVP) but simultaneously inhibits liver regeneration. This interesting paradox motivated us to investigate the outcome of PLF in response to somatostatin treatment. METHODS: Rats receiving extended partial hepatectomy (90% PH) were treated with octreotide, a somatostatin analogue, or placebo. Animal survival, serum parameters and hepatic histology were evaluated. Metabolomic analysis was performed to investigate the effect of octreotide on hepatocyte metabolism. RESULTS: Despite significantly inhibiting early regeneration, octreotide application noticeably improved the hepatic histology, liver function and survival after PH but did not decrease the PVP level. Metabolomic analysis exhibited that octreotide profoundly and exclusively altered the levels of five metabolites that participate in or closely associate with the methionine cycle, a biochemical reaction that uniquely produces S-adenosylmethionine (SAMe), an active methyl residual donor for methyltransferase reactions. Among these metabolites, 5'-methylthioadenosine (MTA), a derivate of SAMe, increased three-fold and was found independently improve the hepatic histology and reduce inflammatory cytokines in hepatectomized rats. CONCLUSIONS: Octreotide exclusively regulates the methionine cycle reaction and augments the MTA level in hepatocytes. MTA prominently protects hepatocytes against shear stress injury and reduces the secondary inflammation, thereby protecting rats from PLF.


Subject(s)
Hepatectomy/adverse effects , Liver Failure , Liver Regeneration , Liver , Octreotide , Animals , Deoxyadenosines/metabolism , Gastrointestinal Agents/administration & dosage , Gastrointestinal Agents/pharmacokinetics , Liver/metabolism , Liver/pathology , Liver Failure/etiology , Liver Failure/metabolism , Liver Failure/pathology , Liver Failure/prevention & control , Liver Regeneration/drug effects , Liver Regeneration/physiology , Male , Octreotide/administration & dosage , Octreotide/pharmacokinetics , Protective Agents/administration & dosage , Protective Agents/pharmacokinetics , Protein O-Methyltransferase/antagonists & inhibitors , Rats , Thionucleosides/metabolism , Treatment Outcome
16.
World J Gastroenterol ; 21(21): 6591-603, 2015 Jun 07.
Article in English | MEDLINE | ID: mdl-26074697

ABSTRACT

AIM: To investigate the continuous hepatic histopathological processes which occur in response to the loss of Dicer1. METHODS: We generated a hepatocyte-selective Dicer1 knockout mouse and observed the gradual hepatic histopathological changes in the mutant liver. Immunohistochemistry and Western blotting were performed to detect Dicer1 expression. We performed hematoxylin and eosin staining, Periodic acid-Schiff staining, Oil Red O staining, and Masson's trichrome staining to detect histological changes in Dicer1-deficient livers. Ki67 immunohistochemistry, terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling assay, and Western blotting were used to determine hepatocyte proliferation and apoptosis. Serum biochemistry, cytokine assays, and flow cytometric analysis were performed to quantity liver necrosis and inflammation. Fibrogenic markers were determined by Western blotting and qPCR. CK19, CD133, and OV6 immunofluorescence were used to observe liver progenitor cells. Immunofluorescence and qPCR were performed to reveal embryonic gene expression. We also performed histological staining and Western blotting to analyze hepatocellular carcinoma (HCC) development. RESULTS: Dicer1 inactivation resulted in significant architecture disorganization and metabolism disruption in the liver. Dicer1 disruption impaired hepatocyte survival and resulted in profound cell apoptosis and continuous necrosis. In contrast to previous reports, the mutant liver exhibited chronic inflammation and progressive fibrosis, and could not be repopulated by Dicer1-positive cells. In addition, extensive activation of hepatic progenitor cells was observed. Primary HCC was observed as early as 4 mo after birth. CONCLUSION: Hepatic loss of Dicer1 results in complex chronic pathological processes, including hepatocyte death, inflammatory infiltration, chronic fibrosis, compensatory proliferation, progenitor activation, and spontaneous hepatocarcinogenesis.


Subject(s)
DEAD-box RNA Helicases/deficiency , Hepatitis, Chronic/enzymology , Hepatocytes/enzymology , Liver/enzymology , Ribonuclease III/deficiency , Stem Cells/enzymology , Animals , Apoptosis , Biomarkers/blood , Carcinoma, Hepatocellular/enzymology , Carcinoma, Hepatocellular/genetics , Carcinoma, Hepatocellular/pathology , Cell Proliferation , Cell Transformation, Neoplastic/genetics , Cell Transformation, Neoplastic/metabolism , Cell Transformation, Neoplastic/pathology , Cytokines/blood , DEAD-box RNA Helicases/genetics , Gene Expression Regulation, Developmental , Genotype , Hepatitis, Chronic/genetics , Hepatitis, Chronic/pathology , Hepatocytes/pathology , Inflammation Mediators/blood , Liver/pathology , Liver Cirrhosis/enzymology , Liver Cirrhosis/genetics , Liver Cirrhosis/pathology , Liver Neoplasms/enzymology , Liver Neoplasms/genetics , Liver Neoplasms/pathology , Mice, Knockout , Necrosis , Phenotype , Ribonuclease III/genetics , Stem Cells/pathology , Time Factors
17.
Exp Ther Med ; 9(3): 733-736, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25667620

ABSTRACT

Diffuse ganglioneuromatosis (DG) of the gastrointestinal tract is a rare condition that is closely associated with neurofibromatosis type 1 and multiple endocrine neoplasia type 2B. The occurrence of DG with multiple schwannomas, which, of the GI tract, usually affect the stomach, is considerably more rare. The present study describes the case of a 54-year-old male with indolent DG, principally involving the small intestine and colon, associated with multiple schwannomas in the subserosa. The patient was treated with surgery. A brief overview of intestinal ganglioneuromatous lesions and the associated conditions is additionally presented.

18.
Zhonghua Yi Shi Za Zhi ; 43(5): 281-4, 2013 Sep.
Article in Chinese | MEDLINE | ID: mdl-24429036

ABSTRACT

Since the end of the Ming Dynasty, western medicine was introduced into China gradually. At first, due to the Chinese were used to traditional Chinese medicine treatment, plus the disgusted attitude toward the malfeasance of western missionaries, the Chinese didn't accept western medical approaches, even with resentment. As the advantages of western medicine gradually revealed, the Chinese felt the magical effects of western medicine in medical practice, and at the same time, the advanced intellectuals were seeking the truth to save the nation and its people, then western medicine were accepted by the Chinese gradually and then spread all over China, reflecting that this process of from conflict between Chinese and western culture to recognition is but, in fact, the cultural conflict between China and the West and its fusion.

19.
Asian Pac J Cancer Prev ; 13(6): 2819-22, 2012.
Article in English | MEDLINE | ID: mdl-22938465

ABSTRACT

OBJECTIVE: To assess induction effects of Chlamydia pneumoniae (Cpn) on lung cancer in rats. METHODS: A lung cancer animal model was developed through repeated intratracheal injection of Cpn (TW-183) into the lungs of rats, with or without exposure to benzo(a)pyrene (Bp). Cpn antibodies (Cpn-IgA, -IgG, and -IgM) in serum were measured by microimmunofluorescence. Cpn-DNA or Cpn-Ag of rat lung cancer was detected through polymerase chain reaction or enzyme-linked immunosorbent assay. RESULTS: The prevalence of Cpn infection was 72.9% (35/48) in the Cpn group and 76.7% (33/43) in the Cpn plus benzo(a)pyrene (Bp) group, with incidences of lung carcinomas in the two groups of 14.6% (7/48) and 44.2% (19/43), respectively (P-values 0.001 and <0.001 compared with normal controls). CONCLUSIONS: A rat model of lung carcinoma induced by Cpn infection was successfully established in the laboratory for future studies on the treatment, prevention, and mechanisms of the disease.


Subject(s)
Chlamydophila Infections/pathology , Chlamydophila pneumoniae , Disease Models, Animal , Lung Neoplasms , Animals , Antibodies, Bacterial/blood , Benzopyrenes , Lung Neoplasms/chemically induced , Lung Neoplasms/microbiology , Rats , Rats, Wistar
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