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Gene expression profiles of Wnt-1 overexpressing melanoma

ABSTRACT: We aimed to analyze the effects of Wnt-1 overexpression on the mRNA expression profile of human melanoma in a mouse xenograft model and correlated the results with then presence or absence of lymphangiogenesis and metastasis. Affymetrix gene expression analysis revealed activation of canonical and non-canonical targets genes in response to Wnt-1 as compared with controls. In regard to lymphangiogenic factors, the amount of VEGF-C was the single best marker to correlate with the amount of lymph-angiogenesis. mRNA expression array of human melanoma orthotopically grown in SCID mice. Comparison includes mRNA expression profile of two melanoma cell-lines (A375 and M24met) stably overexpressing control vector or Wnt-1 treated with or without CsA. Comparison #1 comprised Wnt-1 versus control in A375 and M24met melanoma, respectively. Comparison #2 comprised Wnt-1 + Cyclosporine A (CsA) versus Wnt-1 without CsA.

ORGANISM(S): Homo sapiens

SUBMITTER: Niederleithner H

PROVIDER: S-ECPF-GEOD-26656 | biostudies-other | 2012 Sep

REPOSITORIES: biostudies-other

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Project description:Interferon-alpha (pegylated interferon and ribavirin) is used as standard-of-care therapeutic for chronic hepatitis C virus infection. Besides good cure in some patients other patients do not benefit from the treatment dependent on the virus type and host factors. One class of putative effector proteins is the family of Suppressors of cytokine signalling (SOCS). They act in a classical negative feedback-loop against the action of interferons and many other cytokines. It has been proven that some of them, in particular SOCS1 and SOCS3, inhibit the expression of interferon induced antiviral proteins. Their mode of action depends on the signal they are interfering with. In relation to the interferon-gamma pathway, they are thought to act on the interferon-alpha receptors by masking its recognition site for the Janus kinases (JAK), by blocking the kinase activity of the JAKs and coincidentally hindering STAT molecules from binding to the kinases. They are also thought to ubiquitinate the JAKs resulting in their proteosomal degradation. The function of SOCS proteins in suppressing the interferon-alpha pathway has not yet been characterized exhaustively. This study should unveil links to understand the resistance in interferon-alpha therapy. As results we got almost complete silencing of JAK-STAT signaling in SOCS1 over-expressing cells and tissue-dependent partially suppressed gene induction in SOCS3 over-expressing cell lines. Two human cancer cell lines (ME-15, HuH-7) were stably transfected with pcDNA3.1-SOCS plasmids in presence of geneticin and daughter cell lines were generated after singularization of cells. Next, original cell lines as well as SOCS1 and SOCS3 over-expressing cell lines were treated with 1000 U/ml interferon-alpha for 4 or 24 hours or in normal culture medium. Cells lines obtained from SOCS4 plasmid transfections were screened as additional control. Gene expression levels of cell cultured in control (0 for 4 hours, 2 for 24 hours) or interferon-alpha supplemented medium for 4 hours (1) or 24 hours (4) were analyzed. mRNA abundance was measured in triplicates using 12x8-sample commercial Illumina microarrays (HumanRef 8, version 3) and scanner system (iScan) as well as reagents recommend by Illumina (Illumina® TotalPrep Kit).

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Gene expression profiles of Wnt-1 overexpressing melanoma

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