l-663536 and Liver-Neoplasms

2,5-dimethylcelecoxib (DMC), a derivative of celecoxib, is an inhibitor of microsomal prostaglandin E synthase-1 (mPGES-1). Our previous studies have demonstrated that DMC inhibits the expression of programmed death-ligand 1 on hepatocellular carcinoma (HCC) cells to prevent tumor progression. However, the effect and mechanism of DMC on HCC infiltrating immune cells remain unclear.. In this study, single-cell-based high-dimensional mass cytometry was performed on the tumor microenvironment of HCC mice treated with DMC, celecoxib and MK-886 (a known mPGES-1 inhibitor). Moreover, 16S ribosomal RNA sequencing was employed to analyze how DMC improved the tumor microenvironment of HCC by remodeling the gastrointestinal microflora.. We found that (1) DMC significantly inhibited the growth of HCC and improved the prognosis of the mice, and this depended on the stronger antitumor activity of natural killer (NK) and T cells; (2) compared with celecoxib and MK-886, DMC significantly enhanced the cytotoxic and stem-like potential, and inhibited exhaustion of NK and T cells; (3) mechanistically, DMC inhibited the expression of programmed cell death protein-1 and upregulated interferon-γ expression of NK and T cells via the gastrointestinal microbiota (Bacteroides acidifaciens, Odoribacter laneus, and Odoribacter splanchnicus)-AMPK-mTOR axis.. Our study uncovers the role of DMC in improving the tumor microenvironment of HCC, which not only enriches the relationship between the mPGES-1/prostaglandin E2 pathway and the antitumor function of NK and T cells, but also provide an important strategic reference for multitarget or combined immunotherapy of HCC.Cite Now.

Topics: AMP-Activated Protein Kinases; Animals; Carcinoma, Hepatocellular; Celecoxib; Dinoprostone; Gastrointestinal Microbiome; Liver Neoplasms; Mice; T-Cell Exhaustion; Tumor Microenvironment

Metastasis-associated protein 2 (MTA2) is a member of the metastasis-associated transcriptional regulator family and is a core component of the nucleosome remodeling and histone deacetylation complex. Despite growing evidence that MTA2 plays a crucial role in the tumorigenesis of certain cancers, no systematic pan-cancer analysis of MTA2 is available to date. Therefore, the aim of our study is to explore the prognostic value of MTA2 in 33 cancer types and to investigate its potential immune function.. by comprehensive use of databases from TCGA, GTEx, GEO, UCSC xena, cBioPortal, comPPI, GeneMANIA, TCIA, MSigDB, and PDB, we applied various bioinformatics approaches to investigate the potential role of MTA2, including analyzing the association of MTA2 with MSI, prognosis, gene mutation, and immune cell infiltration in different tumors. We constructed a nomogram in TCGA-LIHC, performed single-cell sequencing (scRNA-seq) analysis of MTA2 in hepatocellular carcinoma (HCC), and screened drugs for the treatment of HCC. Finally, immunohistochemical experiments were performed to verify the expression and prognostic value of MTA2 in HCC. In vitro experiments were employed to observe the growth inhibition effects of MK-886 on the HCC cell line HepG2.. The results suggested that MTA2 was highly expressed in most cancers, and MTA2 expression was associated with the prognosis of different cancers. In addition, MTA2 expression was associated with Tumor Mutation Burden (TMB) in 12 cancer types and MSI in 8 cancer types. Immunoassays indicated that MTA2 positively correlated with activated memory CD4 T cells and M0 macrophage infiltration levels in HCC. ScRNA-seq analysis based on the GEO dataset discovered that MTA2 was significantly expressed in T cells in HCC. Finally, the eXtreme Sum (Xsum) algorithm was used to screen the antitumor drug MK-886, and the molecular docking technique was utilized to reveal the binding capacity between MK-886 and the MTA2 protein. The results demonstrated excellent binding sites between them, which bind to each other through Π-alkyl and alkyl interaction forces. An immunohistochemistry experiment showed that MTA2 protein was highly expressed in HCC, and high MTA2 expression was associated with poor survival in HCC patients. MK-886 significantly inhibited the proliferation and induced cell death of HepG2 cells in a dose-dependent manner.. Our study demonstrated that MTA2 plays crucial roles in tumor progression and tumor immunity, and it could be used as a prognostic marker for various malignancies. MK-886 might be a powerful drug for HCC.

Topics: Carcinoma, Hepatocellular; Drug Evaluation, Preclinical; Early Detection of Cancer; Histone Deacetylases; Humans; Liver Neoplasms; Molecular Docking Simulation; Neoplasms; Prognosis; Repressor Proteins

The issue that lipid metabolism enzyme and its metabolites regulate transcription factors in cancer cell is not fully understood. In this study, we first report that the lipid metabolism enzyme 5-Lipoxygenase (5-LOX) and its metabolite leukotriene B4 (LTB4) are capable of activating nuclear factor-κB (NF-κB) in hepatoma cells. We found that the treatment of MK886 (an inhibitor of 5-LOX) or knockdown of 5-LOX was able to downregulate the expression of NF-κB p65 at the mRNA level and decreased the phosphorylation level of inhibitor κBα (IκBα) in the cytoplasm of hepatoma HepG2 or H7402 cells, which resulted in the decrease of the level of nuclear NF-κB p65. These were confirmed by immunofluorescence staining in HepG2 cell. Moreover, the above treatments were able to decrease the transcriptional activity of NF-κB in the cells. The LTB4, one of metabolites of 5-LOX, is responsible for 5-LOX-activated NF-κB in a dose-dependent manner. Thus, we conclude that the lipid metabolism enzyme 5-LOX and its metabolite LTB4 are capable of activating transcription factor NF-κB in hepatoma cells. Our finding provides new insight into the significance of lipid metabolism in activation of transcription factors in cancer.

Topics: Arachidonate 5-Lipoxygenase; Carcinoma, Hepatocellular; Cell Line, Tumor; Cytoplasm; Gene Expression Regulation, Neoplastic; Humans; I-kappa B Kinase; Indoles; Leukotriene B4; Lipid Metabolism; Lipoxygenase Inhibitors; Liver Neoplasms; NF-kappa B; Transcription Factor RelA; Transcription, Genetic

To study the expression of mPGES-1 in hepatocellular carcinoma (HCC), observe the effect of MK886 on down-regulation of mPGES-1 gene expression on the biology of human hepatocarcinoma cell line HepG2 and to investigate its significance in the occurrence, progression, metastasis and invasion.. HCC tissues, para-carcinoma tissues, far-carcinoma tissues and normal liver tissues were collected. The expressions of mPGES-1 were determined by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot. The proliferation, adherence, migration and invasion abilities of HepG2 cells interfered by MK886 were assessed by MTT and transwell technique respectively.. The expression of mPGES-1 in HCCs was higher than that in normal liver tissues (P < 0.01), which increased following histological grade. Furthermore, mPGES-1 expression level was higher in the capsule invasion and metastasis tumor than in primary locus. A significant dose-dependent down-regulation of expressions of mPGES-1 gene mRNA and protein were observed in HepG2 cells when MK886 was given for 48 h (F = 140.402, P < 0.01; a'= 0.00714, P < 0.01). Compared with the control group, the growth inhibitory rate of HepG2 cell was observed significantly time and dose-dependent when MK886 was given. The rate of adhesion cells in experimental groups were 85.3% ± 1.3%, 70.5% ± 1.5% and 45.8% ± 2.4%, respectively, less than that in control group 100.0% ± 0 (F = 626.313, P < 0.01). The migration cells was 92.47 ± 1.90, 62.63 ± 1.96 and 37.33 ± 0.83 respectively in the experimental groups after 24 h, lower than that in the control group 128.93 ± 2.60 (F = 1253.805, P < 0.01). The invasion assay revealed that the invading cells were 41.67 ± 1.30, 25.47 ± 1.30 and 13.93 ± 1.66 in the experimental groups, in contrast to 55.67 ± 2.08 in control group after 24 h. The difference between these groups was significant (F = 372.615, P < 0.01). The numbers of adhesion, migration and invasion of HepG2 cells were dose-dependent in MK886 groups.. Over-expression of mPGES-1 was associated with the tumorigenesis and progression of HCC. The down-regulation of mPGES-1 gene expression might indicated the decrease of the invasion and metastasis of HCC.

Topics: Carcinoma, Hepatocellular; Cell Adhesion; Cell Movement; Cell Proliferation; Female; Hep G2 Cells; Humans; Indoles; Intramolecular Oxidoreductases; Liver Neoplasms; Male; Microsomes; Neoplasm Invasiveness; Neoplasm Metastasis; Prostaglandin-E Synthases

Peroxisome proliferator-activated receptor (PPAR) agonists such as clofibrate are known to affect liver fatty acid binding protein (L-FABP) levels, which in turn influence hepatocellular oxidant status. The mechanism of clofibrate's modulation of L-FABP levels is not clear. In this study we used clofibrate (PPARα agonist), MK886 (PPARα antagonist), and GW9662 (PPARγ antagonist) in determining the regulating mechanism of L-FABP expression and its antioxidant activity in CRL-1548 hepatoma cells. Antioxidant activity was assessed by determining intracellular reactive oxygen species (ROS) using dichlorofluorescein (DCF) fluorescence. The effect of clofibrate on cytosolic activity of the intracellular antioxidant enzymes was also assessed. RT-PCR and mRNA stability assay showed that clofibrate treatment enhanced L-FABP mRNA stability, which resulted in increased L-FABP levels. A nuclear run-off assay and RT-PCR measurements of L-FABP mRNA revealed that clofibrate increased the L-FABP gene transcription rate. The increased L-FABP was associated with reduced cytosolic ROS. Levels of superoxide dismutase, glutathione peroxidase, and catalase were not affected by clofibrate treatment. L-FABP siRNA knockdown studies showed that a reduction in L-FABP expression was associated with increased DCF fluorescence. We conclude that clofibrate enhanced L-FABP gene transcription and mRNA stability, thus affecting L-FABP expression and ultimately cellular antioxidant activity.

Topics: Anilides; Animals; Carcinoma, Hepatocellular; Catalase; Cell Line, Tumor; Clofibrate; Fatty Acid-Binding Proteins; Fluoresceins; Gene Expression Regulation, Neoplastic; Glutathione Peroxidase; Hepatocytes; Humans; Hydrogen Peroxide; Indoles; Liver Neoplasms; Oxidative Stress; PPAR alpha; Rats; RNA Stability; RNA, Messenger; Superoxide Dismutase