BackgroundThe molecular mechanisms of CC (cholangiocarcinoma) oncogenesis and progression are poorly understood. This study aimed to determine the genome-wide expression of genes related to CC oncogenesis and sarcomatous transdifferentiation.MethodsGenes that were differentially expressed between CC cell lines or tissues and cultured normal biliary epithelial (NBE) cells were identified using DNA microarray technology. Expressions were validated in human CC tissues and cells.ResultsUsing unsupervised hierarchical clustering analysis of the cell line and tissue samples, we identified a set of 342 commonly regulated (>2-fold change) genes. Of these, 53, including tumor-related genes, were upregulated, and 289, including tumor suppressor genes, were downregulated (<0.5 fold change). Expression of SPP1, EFNB2, E2F2, IRX3, PTTG1, PPARγ, KRT17, UCHL1, IGFBP7 and SPARC proteins was immunohistochemically verified in human and hamster CC tissues. Additional unsupervised hierarchical clustering analysis of sarcomatoid CC cells compared to three adenocarcinomatous CC cell lines revealed 292 differentially upregulated genes (>4-fold change), and 267 differentially downregulated genes (<0.25 fold change). The expression of 12 proteins was validated in the CC cell lines by immunoblot analysis and immunohistochemical staining. Of the proteins analyzed, we found upregulation of the expression of the epithelial-mesenchymal transition (EMT)-related proteins VIM and TWIST1, and restoration of the methylation-silenced proteins LDHB, BNIP3, UCHL1, and NPTX2 during sarcomatoid transdifferentiation of CC.ConclusionThe deregulation of oncogenes, tumor suppressor genes, and methylation-related genes may be useful in identifying molecular targets for CC diagnosis and prognosis.
In cancer, VEGF-induced increase in vascular permeability results in increased interstitial pressure, reducing perfusion and increasing hypoxia, which reduce delivery of chemotherapeutic agents and increase resistance to ionizing radiation. Here, we show that both TIMP-2 and Ala ؉ TIMP-2, a TIMP-2 mutant without matrix metalloproteinase inhibitory activity, antagonize the VEGF-A-induced increase in vascular permeability, both in vitro and in vivo. Like other agents known to preserve endothelial barrier function, TIMP-2 elevates cytosolic levels of cAMP and increases cytoskeletal-associated vascular endothelial cadherin in human microvascular endothelial cells. All of these effects are completely ablated by selective knockdown of integrin ␣31 expression, expression of a dominant negative protein tyrosine phosphatase Shp-1 mutant, administration of the protein tyrosine phosphatase inhibitor orthovanadate, or the adenylate cyclase inhibitor SQ22536. This TIMP-2-mediated inhibition of vascular permeability involves an integrin ␣31-Shp-1-cAMP/protein kinase A-dependent vascular endothelial cadherin cytoskeletal association, as evidenced by using siRNAs to integrin ␣31 and Shp-1, or treatment with Shp-1 inhibitor NSC87877 and protein kinase A inhibitor H89. Our results demonstrate the potential utility for TIMP-2 in cancer therapy through "normalization" of vascular permeability in addition to previously described antiangiogenic effects. (Blood. 2012;120(24):4892-4902) IntroductionTumor-associated angiogenesis is critical for tumor progression and metastasis. The central role of vascular endothelial growth factor-A (VEGF-A) in this process is evidenced by the development and approval of bevacizumab, a VEGF-A neutralizing antibody, for therapy in several human cancers. VEGF-A-induced angiogenesis is often accompanied by increased vascular permeability, which can result in fibrin deposition and may facilitate tumor cell extravasation enhancing metastasis formation. 1 The resulting vascular leak has also been shown to increase interstitial pressure within the tumor, decrease tumor blood flow, and hinder drug delivery to the tumor. Indeed, it has been proposed that VEGF-axis targeted therapies may result in "normalization" of tumor vasculature improving chemotherapeutic delivery and decreasing hypoxia, resulting in enhanced radiosensitivity. 2,3 Vascular permeability can be modulated by the phosphorylation, cleavage, and internalization of vascular endothelial (VE)-cadherin. [4][5][6] Tyrosine phosphorylation of the cadherin-catenin complexes is regulated by the activities of protein tyrosine phosphatases and src-family kinases. 7-11 Inhibition of tyrosine phosphorylation of VE-cadherin increases the stability of adherens junctions and improves vascular barrier function. Matrix metalloproteinase (MMP)-mediated cleavage of VE-cadherin may promote vascular permeability and cell proliferation by dissociating cadherin-catenin complex and disrupting cell-cell adhesion. [12][13][14][15] In contrast, it is widely recognized t...
Adenophora triphylla var. japonica (Campanulaceae) is known to have anti-inflammatory and anti-tussive effects. Dysfunction of adipocytes and adipose tissue in obesity is related to various inflammatory cytokines or adipokines. In this study, we investigated whether lupenone isolated from A. triphylla var. japonica extract inhibits adipocyte differentiation and expression of adipogenic marker genes in 3T3-L1 preadipocytes. We demonstrated that lupenone resulted in a significant reduction in lipid accumulation and expression of adipogenic marker genes in a dose-dependent manner. In addition, lupenone decreased the transcriptional activity of peroxisome proliferator-activated receptor γ (PPARγ) induced by troglitazone, and we also demonstrated that lupenone suppressed the PPARγ and CCAAT-enhancer-binding protein α (C/EBPα) protein levels. These findings demonstrated that lupenone isolated from A. triphylla var. japonica extract effectively inhibited adipocyte differentiation through downregulation of related transcription factor, particularly the PPARγ gene.
The human MUC6 gene, which is reported to be expressed in the stomach and gall bladder, is clustered on chromosome 11p15.5 with other secreted mucins. In this study, the genomic structure of MUC6 has been analyzed and five VNTR (minisatellites; MS1-MS5) were identified. These minisatellites were analyzed in genomic DNA extracted from 1,103 controls, 470 gastric cancer patients, and multigenerational families. Five novel minisatellites were found to be polymorphic and transmitted through meiosis by Mendelian inheritance in families. We evaluated allelic variation in these minisatellites to determine if such variation affected the susceptibility to gastric cancer. A significant association (odds ratio [OR]=7.08) between short rare MUC6-MS5 alleles and relative risks were observed for gastric cancer (95% confidence interval [CI], 1.43-35.19; P=0.005). To investigate the function of minisatellite alleles of MUC6-MS5, we examined the effects on gene expression from luciferase reporters when inserted with minisatellites. Interestingly, when the shortest allele (7TR) was inserted in the promoter, the expression level decreased over 20-fold (P<0.001) in normal and cancer cell lines. Furthermore, the cancer-specific rare allele (TR8) also showed decreased expression levels in cancer cells. Therefore, we suggest that the short rare MUC6-MS5 alleles may be related to cancer development by the regulation of MUC6 expression.
Tribulus terrestris (T. terrestris) has been used as a traditional medicine for the treatment of a variety of diseases, including inflammation, edema and hypertension. The aqueous and ethanol extracts of T. terrestris contain alkaloids, flavonoids, tannins, quinines and phenolic compounds. Tribulusamide D is a compound that has been isolated from the ethanol extract of T. terrestris. The present study investigated the anti-inflammatory effect of tribulusamide D on lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. Tribulusamide D inhibited the production of LPS-induced nitric oxide and prostaglandin E2, by reducing the expression of inducible nitric oxide synthase and cyclooxygenase-2 expression, respectively. The expression of these genes associated with inflammation was determined using reverse transcription-polymerase chain reaction and western blot analysis. Furthermore, tribulusamide D reduced the expression of LPS-induced inflammatory cytokines, including interleukin (IL)-6, IL-10 and tumor necrosis factor-α. They were quantified using an enzyme-linked immunosorbent assay. In addition, the present study confirmed that the inhibitory effects of tribulusamide D on the inflammatory response were mediated through inactivation of mitogen-activated protein kinase p38 and inhibition of nuclear localization of nuclear factor-B, which were also determined by western blot analysis. To the best of our knowledge, the current study is the first to demonstrate that tribulusamide D exerts anti-inflammatory activity by altering the expression of inflammatory mediators and cytokines, indicating that tribulusamide D could be developed as a potential therapeutic agent for the treatment of inflammatory disorders.
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