The scaffolding protein Flot2 regulates cytoneme-based transport of Wnt3 in gastric cancer

The Wnt/β-catenin signalling pathway regulates multiple cellular processes during development and many diseases, including cell proliferation, migration, and differentiation. Despite their hydrophobic nature, Wnt proteins exert their function over long distances to induce paracrine signalling. Recent studies have identified several factors involved in Wnt secretion, however, our understanding of how Wnt ligands are transported between cells to interact with their cognate receptors is still debated. Here, we demonstrate that gastric cancer cells utilise cytonemes to transport Wnt3 intercellularly to promote proliferation. Furthermore, we identify the membrane-bound scaffolding protein Flotillin-2 (Flot2), frequently overexpressed in gastric cancer, as a regulator of these cytonemes. Together with the Wnt co-receptor and cytoneme initiator Ror2, Flot2 determines the number and length of Wnt3 cytonemes in gastric cancer. Finally, we show that Flot2 is necessary for Wnt8a cytonemes during zebrafish embryogenesis, suggesting a conserved mechanism for Flot2-mediated Wnt transport on cytonemes in development and disease.

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Demonstration of the efficacy of compound CFAK-C4 targeting FAK-VEGFR3 protein-protein interaction in gastric cancer.

Journal of Clinical Oncology ◽

10.1200/jco.2013.31.15_suppl.e22143 ◽

2013 ◽

Vol 31 (15_suppl) ◽

pp. e22143-e22143

Author(s):

Elena V. Kurenova ◽

Sartaj Singh Sanghera ◽

Jianqun Liao ◽

Michael Yemma ◽

William G. Cance

Keyword(s):

Gastric Cancer ◽

Tumor Growth ◽

Tumor Progression ◽

Colony Formation ◽

Tumor Regression ◽

Cancer Therapeutics ◽

Scaffolding Protein ◽

Dependent Manner ◽

Gastric Cancer Cells

e22143 Background: While the emerging data strongly suggest that FAK is an excellent target for developmental therapeutics of cancer, kinase inhibitors of FAK have shown crossreactivity with other protein kinases and toxicity in preclinical and clinical studies. It is known that FAK acts pleiotropically, as a kinase and as a scaffolding protein, and our goal is to explore targeting the scaffolding function of FAK to inhibit protein-protein interactions important for tumor progression. Previously, we have shown that FAK physically interacts with VEGFR3 and we identified small molecule inhibitor CFAK-C4 that targets this site of interaction. Both of these kinases are overexpressed in gastric cancers and were found to be independent poor prognostic factors. The prognosis of patients with gastric cancer remains unfavorable and molecular based treatments are necessary for a potential breakthrough in the therapy of this disease. We hypothesize that FAK-VEGFR3 interaction provides essential survival signals for gastric tumor growth and that simultaneous inhibition of these signals will inhibit tumor progression. Methods: Effects of CFAK-C4 on gastric cancer cell lines AGS and NCI-N87 were examined by MTT assay (viability), colony formation assay and Western blotting (phosphorylation, apoptosis). Subcutaneous mouse model was used to demonstrate effect of CFAK-C4 in vivo. Results: CFAK-C4 specifically blocked phosphorylation of VEGFR3 and FAK, directly inhibited cell viability (p<0.05), increased cell detachment and inhibited colony formation in a dose-dependent manner (range 1-100µM). CFAK-C4 (50mg/kg, IP) effectively caused tumor regression in vivo, when administered alone and its effects were synergistic (p<0.05) with chemotherapy. In vivo effects of C4 were confirmed by a decrease in tumor FAK and VEGFR3 phosphorylation, and disruption of their complexes. Conclusions: In this study we have shown that CFAK-C4 inhibits FAK-VEGFR3 signaling in gastric cancer cells and affects tumor growth. This result demonstrates that targeting the scaffolding function of FAK is a unique approach of highly-specific molecular-targeted therapy and can be used to develop oral-based cancer therapeutics.

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RACK1 to modulate expression of MMP10 via Src/NF-κB pathway in gastric cancer.

Journal of Clinical Oncology ◽

10.1200/jco.2017.35.15_suppl.e15529 ◽

2017 ◽

Vol 35 (15_suppl) ◽

pp. e15529-e15529

Author(s):

Ling Chen ◽

Hao Chen ◽

Fenglin Liu

Keyword(s):

Gastric Cancer ◽

Inverse Correlation ◽

Good Prognosis ◽

Dominant Negative ◽

Scaffolding Protein ◽

Migration And Invasion ◽

Enzyme Linked Immunosorbent Assay ◽

Gastric Cancer Cells ◽

Antibody Arrays

e15529 Background: Receptor of activated C kinase 1 (RACK1) is regarded as a scaffolding protein in multiple intracellular signal transduction pathways. Our previous works had demonstrated that RACK1 might involve in progression of gastric cancer, and could be a criterion to predict the good prognosis for the patients after surgical resection. The aim of this study is to explore the regulatory role of RACK1 in matrix metalloproteinase 10 (MMP10) autocrine, and which may be involved in invasion of gastric cancer. Methods: RACK1 knockdown gastric cell lines were established by shRNA. Secretion of cytokines secretion, as well as MMP10 was measured by antibody arrays and enzyme-linked immunosorbent assay. Cell migration and invasion was compared between normal and RACK1 knockdown cells. Pharmacological inhibitors were employed in searching specific signaling pathway. The correlation of RACK1 and MMP10 expression in gastric cancer samples was analyzed by Spearman’s ρ test. Results: Expression of MMP10 was substantially enhanced after knockdown of RACK1 in vitro, which contributed to enhanced migration and invasiveness of gastric cancer cells in autocrine manner. Specific inhibitors of NF-κB and c-Src, as well as overexpression of dominant-negative c-Src mutant, could suppress the expression of MMP10. Finally, an inverse correlation of RACK1 and IL-8 expression was confirmed in gastric cancer samples. Conclusions: Down-regulation of RACK1 resulted in the up-regulation of MMP10 in gastric cancer, which might enhance invasiveness via Src/NF-κB pathway partially.

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Membrane-bound β-catenin degradation is enhanced by ETS2-mediated Siah1 induction in Helicobacter pylori-infected gastric cancer cells

Oncogenesis ◽

10.1038/oncsis.2017.26 ◽

2017 ◽

Vol 6 (5) ◽

pp. e327-e327 ◽

Cited By ~ 7

Author(s):

L Das ◽

S B Kokate ◽

P Dixit ◽

S Rath ◽

N Rout ◽

...

Keyword(s):

Gastric Cancer ◽

Helicobacter Pylori ◽

Cancer Cells ◽

Gastric Cancer Cells ◽

Membrane Bound

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Alpha-fetoprotein producing gastric cancer cells lack transcription factor AT-motif binding factor 1 (ATBF1)

Gastroenterology ◽

10.1016/s0016-5085(01)80153-0 ◽

2001 ◽

Vol 120 (5) ◽

pp. A31-A31

Author(s):

H KATAOKA ◽

T JOH ◽

T OHSHIMA ◽

Y ITOH ◽

K SENOO ◽

...

Keyword(s):

Gastric Cancer ◽

Transcription Factor ◽

Cancer Cells ◽

Alpha Fetoprotein ◽

Gastric Cancer Cells ◽

Binding Factor

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Distinct mechanism of helicobacter pylori-mediated NF-κB activation between gastric cancer cells, MKN45 and monocystic cells, THP-1

Gastroenterology ◽

10.1016/s0016-5085(01)80402-9 ◽

2001 ◽

Vol 120 (5) ◽

pp. A82-A82 ◽

Cited By ~ 1

Author(s):

S MAEDA ◽

Y MITSUNO ◽

Y HIRATA ◽

M AKANUMA ◽

H YOSHIDA ◽

...

Keyword(s):

Gastric Cancer ◽

Helicobacter Pylori ◽

Cancer Cells ◽

Gastric Cancer Cells ◽

Distinct Mechanism

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Some Aspects of the Polyhexamethyleneguanidine Salts Effect on Cell Cultures

Agricultural science and practice ◽

10.15407/agrisp1.01.062 ◽

2014 ◽

Vol 1 (1) ◽

pp. 62-67 ◽

Cited By ~ 2

Author(s):

M. Mandygra ◽

A. Lysytsia

Keyword(s):

Proliferative Activity ◽

Cell Monolayer ◽

Eukaryotic Cell ◽

Culture Methods ◽

Cellular Processes ◽

Negative Effect ◽

Membrane Bound ◽

Membrane Bound Enzymes ◽

Anion Type ◽

Cell Culture Methods

Aim. To investigate the effect of polyhexamethyleneguanidine (PHMG) to eukaryotic cell culture. Methods. The passaged bovine tracheal cells culture (TCC) and primary culture of chicken embryo fi broblasts (FCE) were used in the experiments. TCC and FCE monolayers were treated with aqueous solutions of PHMG chloride or succinate. The method of PHMG polycation adsorption to the cells’ plasma membrane together with microscopy were applied. Results. The dependence of PHMG effect on the eukaryotic cells on the agent concentration, duration of exposure and the anion type has been fi xed. The PHMG concentration of 10 –5 per cent (0.1 μg/ml) never causes degradation of the previously formed cell monolayer, while the higher concentrations damage it. The conditions of the PHMG chloride and succinate’s negative effect on cell proliferation and inhibition of monolayer formation were determined. The hypothesis that under certain conditions PHMG stimulates the proliferative activity of the cells has been confi rmed. Stimulation may be associated with non-specifi c stress adaptation of cells. In this case, it is due to modifi cations of the cell membrane after PHMG adsorption to it. Conclusions. PHMG polycation binds with the membrane’s phosphoglycerides fi rmly and irreversibly. A portion of the lipids are removed from participation in the normal cellular processes at that. At the same time, the synthesis of new lipids and membrane-bound enzymes is probably accelerated. The phospholip ids’ neogenesis acceleration can stimulate mitosis under certain conditions. The obtained results can be used in the biotechnologies.

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