Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0024623 (gastric cancer)
 36,219 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Hedgehog, BMP/TGFbeta, FGF, WNT and Notch signaling pathways constitute the stem cell signaling network, which plays a key role in a variety of processes, such as embryogenesis, maintenance of adult tissue homeostasis, tissue repair during chronic persistent inflammation, and carcinogenesis. Sonic hedgehog (SHH), Indian hedgehog (IHH) and Desert hedgehog (DHH) bind to PTCH1/PTCH or PTCH2 receptor to release Smoothened (SMO) signal transducer from Patched-dependent suppression. SMO then activates STK36 serine/threonine kinase to stabilize GLI family members and to phosphorylate SUFU for nuclear accumulation of GLI. Hedgehog signaling activation leads to GLI-dependent transcriptional activation of target genes, such as GLI1, PTCH1, CCND2, FOXL1, JAG2 and SFRP1. GLI1-dependent positive feedback loop combined with PTCH1-dependent negative feedback loop gives rise to transient proliferation of Hedgehog target cells. Iguana homologs (DZIP1 and DZIP1L) and Costal-2 homologs (KIF7 and KIF27) are identified by comparative integromics. SHH-dependent parietal cell proliferation is implicated in gastric mucosal repair during chronic Helicobacter pylori infection. BMP-RUNX3 signaling induces IHH expression in surface differentiated epithelial cells of stomach and intestine. Hedgehog signals from epithelial cells then induces FOXL1-mediated BMP4 upregulation in mesenchymal cells. Hedgehog signaling is frequently activated in esophageal cancer, gastric cancer and pancreatic cancer due to transcriptional upregulation of Hedgehog ligands and epigenetic silencing of HHIP1/HHIP gene, encoding the Hedgehog inhibitor. However, Hedgehog signaling is rarely activated in colorectal cancer due to negative regulation by the canonical WNT signaling pathway. Hedgehog signaling molecules or targets, such as SHH, IHH, HHIP1, PTCH1 and GLI1, are applied as biomarkers for cancer diagnostics, prognostics and therapeutics. Small-molecule inhibitors for SMO or STK36 are suitable to be used for treatment of Hedgehog-dependent cancer.
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PMID:Hedgehog signaling pathway and gastrointestinal stem cell signaling network (review). 1708 4

Transforming growth factor (TGF)-beta plays a pivotal role in regulation of progression of cancer through effects on tumor microenvironment as well as on cancer cells. TGF-beta inhibitors have recently been shown to prevent the growth and metastasis of certain cancers. However, there may be adverse effects caused by TGF-beta signaling inhibition, including the induction of cancers by the repression of TGF-beta-mediated growth inhibition. Here, we present an application of a short-acting, small-molecule TGF-beta type I receptor (TbetaR-I) inhibitor at a low dose in treating several experimental intractable solid tumors, including pancreatic adenocarcinoma and diffuse-type gastric cancer, characterized by hypovascularity and thick fibrosis in tumor microenvironments. Low-dose TbetaR-I inhibitor altered neither TGF-beta signaling in cancer cells nor the amount of fibrotic components. However, it decreased pericyte coverage of the endothelium without reducing endothelial area specifically in tumor neovasculature and promoted accumulation of macromolecules, including anticancer nanocarriers, in the tumors. Compared with the absence of TbetaR-I inhibitor, anticancer nanocarriers exhibited potent growth-inhibitory effects on these cancers in the presence of TbetaR-I inhibitor. The use of TbetaR-I inhibitor combined with nanocarriers may thus be of significant clinical and practical importance in treating intractable solid cancers.
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PMID:Improvement of cancer-targeting therapy, using nanocarriers for intractable solid tumors by inhibition of TGF-beta signaling. 1730 70

Radiotherapy is an effective treatment for some esophageal cancers, but the molecular mechanisms of radiosensitivity remain unknown. RUNX3, a novel tumor suppressor of gastric cancer, functions in transforming growth factor (TGF)-beta-dependent apoptosis. We obtained paired samples from 62 patients with advanced esophageal cancers diagnosed initially as T3 or T4 with image diagnosis; one sample was obtained from a biopsy before presurgical radiotherapy, and the other was resected in surgical specimens after radiotherapy. RUNX3 was repressed in 67.7% cases of the pretreatment biopsy samples and 96.7% cases of the irradiated, resected samples. The nuclear expression of RUNX3 was associated with radiosensitivity and a better prognosis than cytoplasmic or no RUNX3 expression (P<0.003); cytoplasmic RUNX3 expression was strictly associated with radioresistance. RUNX3 was downregulated and its promoter was hypermethylated in all radioresistant esophageal cancer cell lines examined. Stable transfection of esophageal cancer cells with RUNX3 slightly inhibited cell proliferation in vitro, enhanced the antiproliferative and apoptotic effects of TGF-beta and increased radiosensitivity in conjunction with Bim induction. In contrast, transfection of RUNX3-expressing cells with a RUNX3 antisense construct or a Bim-specific small interfering RNA induced radioresistance. Treatment with 5-aza-2'-deoxycytidine restored RUNX3 expression, increased radiosensitivity and induced Bim in both control and radioresistant cells. These results suggest that RUNX3 silencing promotes radioresistance in esophageal cancers. Examination of RUNX3 expression in pretreatment specimens may predict radiosensitivity, and induction of RUNX3 expression may increase tumor radiosensitivity.
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PMID:Frequent silencing of RUNX3 in esophageal squamous cell carcinomas is associated with radioresistance and poor prognosis. 1738 82

Defining apoptosis-regulatory cascades of the epithelium is important for understanding carcinogenesis, since cancer cells are considered to arise as a result of the collapse of the cascades. We previously reported that a novel gene GASDERMIN (GSDM) is expressed in the stomach but suppressed in gastric cancer cell lines. Furthermore, in this study, we demonstrated that GSDM is expressed in the mucus-secreting pit cells of the gastric epithelium and frequently silenced in primary gastric cancers. We found that GSDM has a highly apoptotic activity and its expression is regulated by a transcription factor LIM domain only 1 (LMO1) through a sequence to which Runt-related transcription factor 3 (RUNX3) binds, in a GSDM promoter region. We observed coexpression of GSDM with LMO1, RUNX3 and type II transforming growth factor-beta receptor (TGF-betaRII) in the pit cells, and found that TGF-beta upregulates the LMO1- and GSDM-expression in the gastric epithelial cell line and induces apoptosis, which was confirmed by the finding that the apoptosis induction is inhibited by suppression of each LMO1-, RUNX3- and GSDM expression, respectively. The present data suggest that TGF-beta, LMO1, possibly RUNX3, and GSDM form a regulatory pathway for directing the pit cells to apoptosis.
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PMID:GASDERMIN, suppressed frequently in gastric cancer, is a target of LMO1 in TGF-beta-dependent apoptotic signalling. 1747 Dec 40

To be able to describe the differences between the normal and tumor tissues of gastric cancer at a molecular level would be essential in the study of the disease. We investigated the gene expression pattern in the two types of tissues from gastric cancer by performing expression profiling of 86 tissues on 17K complementary DNA microarrays. To select for the differentially expressed genes, class prediction algorithm was employed. For predictor selection, samples were first divided into a training (n=58), and a test set (n=28). A group of 894 genes was selected by a t-test in a training set, which was used for cross-validation in the training set and class (normal or tumor) prediction in the test set. Smaller groups of 894 genes were individually tested for their ability to correctly predict the normal or tumor samples based on gene expression pattern. The expression ratios of the 5 genes chosen from microarray data can be validated by real time RT-PCR over 6 tissue samples, resulting in a high level of correlation, individually or combined. When a representative predictor set of 92 genes was examined, pathways of 'focal adhesion' (with gene components of THBS2, PDGFD, MAPK1, COL1A2, COL6A3), 'ECM-receptor interaction' pathway (THBS2, COL1A2, COL6A3, FN1) and 'TGF-beta signaling' (THBS2, MAPK1, INHBA) represent some of the main differences between normal and tumor of gastric cancer at a molecular level.
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PMID:Molecular basis of the differences between normal and tumor tissues of gastric cancer. 1760 8

It is known that the activation of hedgehog (Hh) signaling is involved in the progression and invasion of various tumors, including gastric carcinoma. In this study, we investigated the impact of transforming growth factor (TGF)-beta signaling on the sonic hedgehog (Shh)-mediated invasion of gastric cancer cells. We found that higher concentrations of N-Shh enhanced cell motility and invasiveness in gastric cancer cells, whereas no increase was observed in cells that were treated with KAAD-cyclopamine (a Shh signaling inhibitor) or anti-Shh blocking antibodies. In addition, the N-Shh-induced migration and invasiveness of gastric cancer cells were reduced by treatment with anti-TGF-beta blocking antibody or TGF-beta1 small interfering RNA (siRNA) in presence of N-Shh when compared with control groups. Furthermore, TGF-beta1 secretion, TGF-beta-mediated transcriptional response, expression of activin receptor-like kinase (ALK) 5 protein and phosphorylation of Smad 3 were also enhanced by treatment with N-Shh, but not KAAD-cyclopamine, anti-Shh or TGF-beta1 blocking antibodies. Blockade of the ALK5 kinase in the presence of N-Shh significantly inhibited phosphorylation of Smad 3, activity of matrix metalloproteinases and Shh-induced cell motility/invasiveness. Importantly, transient expression of ALK5 siRNA or Smad 3 siRNA reduced the ability of N-Shh to stimulate migration and invasion of those cells compared with the cells treated with non-specific control siRNA. In summary, these results indicate that Shh promotes motility and invasiveness of gastric cancer cells through TGF-beta-mediated activation of the ALK5-Smad 3 pathway. Additionally, our findings are the first to suggest a role and mechanism for Shh signaling as it relates to the metastatic potential of gastric cancer, thereby indicating potential therapeutic molecular targets to decrease metastasis.
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PMID:Sonic hedgehog signaling promotes motility and invasiveness of gastric cancer cells through TGF-beta-mediated activation of the ALK5-Smad 3 pathway. 1817 46

Deregulation of E2F1 activity and resistance to TGFbeta are hallmarks of gastric cancer. MicroRNAs (miRNAs) are small noncoding RNAs frequently misregulated in human malignancies. Here we provide evidence that the miR-106b-25 cluster, upregulated in a subset of human gastric tumors, is activated by E2F1 in parallel with its host gene, Mcm7. In turn, miR-106b and miR-93 regulate E2F1 expression, establishing a miRNA-directed negative feedback loop. Furthermore, upregulation of these miRNAs impairs the TGFbeta tumor suppressor pathway, interfering with the expression of CDKN1A (p21(Waf1/Cip1)) and BCL2L11 (Bim). Together, these results suggest that the miR-106b-25 cluster is involved in E2F1 posttranscriptional regulation and may play a key role in the development of TGFbeta resistance in gastric cancer.
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PMID:E2F1-regulated microRNAs impair TGFbeta-dependent cell-cycle arrest and apoptosis in gastric cancer. 1832 30

Chronic inflammation in the stomach induces cellular transformation and gastric cancer primarily in the distal stomach or antrum. In this issue of the JCI, a study in mice by Ernst et al. provides new insight into the role of IL-11 and its glycoprotein 130 (gp130) receptor in inflammation-associated gastric epithelial cell oncogenic transformation, which they show is mediated by and dependent on increased activation of Stat3 and, to a lesser extent, Stat1 (see the related article beginning on page 1727). Prior studies from this group have shown that Stat3 hyperactivity stimulates the TGF-beta inhibitor Smad7. Collectively, the studies suggest that an important pathway of oncogenic transformation in the stomach is through suppression of growth inhibitory signals, such as members of the TGF-beta family, that originate from the stroma.
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PMID:What lurks beneath: IL-11, via Stat3, promotes inflammation-associated gastric tumorigenesis. 1843 20

Hedgehog-binding to Patched family receptors results in Smoothened-mediated activation of MAP3K10 (MST) and inactivation of SUFU. MAP3K10-induced DYRK2 phosphorylation combined with SUFU inhibition results in the stabilization and nuclear accumulation of GLI2 for transcriptional activation of GLI1, CCND1, CCND2, FOXA2, FOXC2, FOXP3, FOXQ1, RUNX2, and JAG2. Here, integrative genomic analyses on GLI2 orthologs were carried out. Rat Gli2 complete coding sequence was determined by assembling nucleotide sequences of exons 1, 2, and 5'-truncated rat Gli2 RefSeq (NM_001107169.1). GLI2 orthologs were more related to GLI3 orthologs than to GLI1 orthologs lacking the N-terminal repressor domain. betaTRCP1 (FBXW1)-binding DSYxxxS motif was conserved in GLI2 and GLI3 orthologs, while betaTRCP2 (FBXW11)-binding DSGxxxxxxxxxS motif in GLI2 and GLI1 orthologs. Human GLI2 mRNA was expressed in ES cells, NT2 cells, fetal lung, fetal heart, regenerating liver, gastric cancer, and other tumors. Mouse Gli2 mRNA was expressed in unfertilized egg, ES cells, and EG cells. Tandem RRRCWWGYYY motifs for P53, P63 or P73, and also four conserved bHLH-binding sites were identified within GLI2 proximal promoter region. Interaction map of P53 and stem cell signaling network were then constructed. P53-induced NOTCH1 upregulation leads to HES1, HES5, HEY1, HEY2 or HEYL upregulation for the repression of tissue specific bHLH transcriptional activators. DYRK2 functions as a positive regulator of P53-mediated apoptosis, and also as a negative regulator of the Hedgehog signaling cascade. GLI2 expression is regulated based on the balance of P53, Notch, and TGF-beta signaling, and Hedgehog signaling activation results in cell survival and proliferation due to transcriptional activation of Hedgehog-target genes, and also partly due to perturbation of P53-mediated transcriptional regulation.
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PMID:Integrative genomic analyses on GLI2: mechanism of Hedgehog priming through basal GLI2 expression, and interaction map of stem cell signaling network with P53. 1881 3

Chromosomal amplification occurs frequently in solid tumors and is associated with poor prognosis. Several reports demonstrated the cooperative effects of oncogenic factors in the same amplicon during cancer development. However, the functional correlation between the factors remains unclear. Transforming growth factor (TGF)-beta signaling plays important roles in cytostasis and normal epithelium differentiation, and alterations in TGF-beta signaling have been identified in many malignancies. Here, we demonstrated that transcriptional co-repressors of TGF-beta signaling, SKI and MDS1/EVI1-like gene 1 (MEL1), were aberrantly expressed in MKN28 gastric cancer cells by chromosomal co-amplification of 1p36.32. SKI and MEL1 knockdown synergistically restored TGF-beta responsiveness in MKN28 cells and reduced tumor growth in vivo. MEL1 interacted with SKI and inhibited TGF-beta signaling by stabilizing the inactive Smad3-SKI complex on the promoter of TGF-beta target genes. These findings reveal a novel mechanism where distinct transcriptional co-repressors are co-amplified and functionally interact, and provide molecular targets for gastric cancer treatment.
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PMID:SKI and MEL1 cooperate to inhibit transforming growth factor-beta signal in gastric cancer cells. 1904 80


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