Epigenetic regulation of the secreted frizzled-related protein family in human glioblastoma multiforme
Glioblastoma multiforme (GBM) are intracranial tumors of the central nervous system and the most lethal among solid tumors. Current therapy is palliative and is limited to surgical resection followed by radiation therapy and temozolomide treatment. Aberrant WNT pathway activation mediates not only c...
| Main Authors: | , , , , , , , |
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| Format: | Journal Article |
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Nature Publishing Group
2014
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| Online Access: | http://hdl.handle.net/20.500.11937/10003 |
| _version_ | 1848746109839605760 |
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| author | Schiefer, L. Visweswaran, Malini Perumal, Vanathi Arfuso, Frank Groth, David Newsholme, Philip Warrier, Sudha Dharmarajan, Arunasalam |
| author_facet | Schiefer, L. Visweswaran, Malini Perumal, Vanathi Arfuso, Frank Groth, David Newsholme, Philip Warrier, Sudha Dharmarajan, Arunasalam |
| author_sort | Schiefer, L. |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | Glioblastoma multiforme (GBM) are intracranial tumors of the central nervous system and the most lethal among solid tumors. Current therapy is palliative and is limited to surgical resection followed by radiation therapy and temozolomide treatment. Aberrant WNT pathway activation mediates not only cancer cell proliferation but also promotes radiation and chemotherapeutic resistance. WNT antagonists such as the secreted frizzled-related protein (sFRP) family have an ability to sensitize glioma cells to chemotherapeutics, decrease proliferation rate and induce apoptosis. During tumor development, sFRP genes (1–5) are frequently hypermethylated, causing transcriptional silencing. We investigated a possible involvement of methylation-mediated silencing of the sFRP gene family in human GBM using four human glioblastoma cell lines (U87, U138, A172 and LN18). To induce demethylation of the DNA, we inhibited DNA methyltransferases through treatment with 5-azacytidine. Genomic DNA, RNA and total protein were isolated from GBM cells before and after treatment. We utilized bisulfite modification of genomic DNA to examine the methylation status of the respective sFRP promoter regions. Pharmacological demethylation of the GBM cell lines demonstrated a loss of methylation in sFRP promoter regions, as well as an increase in sFRP gene-specific mRNA abundance. Western blot analysis demonstrated an increased protein expression of sFRP-4 and increased levels of phosphorylated-ß-catenin. These data indicate an important role of methylation-induced gene silencing of the sFRP gene family in human GBM. |
| first_indexed | 2025-11-14T06:28:02Z |
| format | Journal Article |
| id | curtin-20.500.11937-10003 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| last_indexed | 2025-11-14T06:28:02Z |
| publishDate | 2014 |
| publisher | Nature Publishing Group |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-100032017-09-13T14:53:17Z Epigenetic regulation of the secreted frizzled-related protein family in human glioblastoma multiforme Schiefer, L. Visweswaran, Malini Perumal, Vanathi Arfuso, Frank Groth, David Newsholme, Philip Warrier, Sudha Dharmarajan, Arunasalam Glioblastoma multiforme (GBM) are intracranial tumors of the central nervous system and the most lethal among solid tumors. Current therapy is palliative and is limited to surgical resection followed by radiation therapy and temozolomide treatment. Aberrant WNT pathway activation mediates not only cancer cell proliferation but also promotes radiation and chemotherapeutic resistance. WNT antagonists such as the secreted frizzled-related protein (sFRP) family have an ability to sensitize glioma cells to chemotherapeutics, decrease proliferation rate and induce apoptosis. During tumor development, sFRP genes (1–5) are frequently hypermethylated, causing transcriptional silencing. We investigated a possible involvement of methylation-mediated silencing of the sFRP gene family in human GBM using four human glioblastoma cell lines (U87, U138, A172 and LN18). To induce demethylation of the DNA, we inhibited DNA methyltransferases through treatment with 5-azacytidine. Genomic DNA, RNA and total protein were isolated from GBM cells before and after treatment. We utilized bisulfite modification of genomic DNA to examine the methylation status of the respective sFRP promoter regions. Pharmacological demethylation of the GBM cell lines demonstrated a loss of methylation in sFRP promoter regions, as well as an increase in sFRP gene-specific mRNA abundance. Western blot analysis demonstrated an increased protein expression of sFRP-4 and increased levels of phosphorylated-ß-catenin. These data indicate an important role of methylation-induced gene silencing of the sFRP gene family in human GBM. 2014 Journal Article http://hdl.handle.net/20.500.11937/10003 10.1038/cgt.2014.30 Nature Publishing Group fulltext |
| spellingShingle | Schiefer, L. Visweswaran, Malini Perumal, Vanathi Arfuso, Frank Groth, David Newsholme, Philip Warrier, Sudha Dharmarajan, Arunasalam Epigenetic regulation of the secreted frizzled-related protein family in human glioblastoma multiforme |
| title | Epigenetic regulation of the secreted frizzled-related protein family in human glioblastoma multiforme |
| title_full | Epigenetic regulation of the secreted frizzled-related protein family in human glioblastoma multiforme |
| title_fullStr | Epigenetic regulation of the secreted frizzled-related protein family in human glioblastoma multiforme |
| title_full_unstemmed | Epigenetic regulation of the secreted frizzled-related protein family in human glioblastoma multiforme |
| title_short | Epigenetic regulation of the secreted frizzled-related protein family in human glioblastoma multiforme |
| title_sort | epigenetic regulation of the secreted frizzled-related protein family in human glioblastoma multiforme |
| url | http://hdl.handle.net/20.500.11937/10003 |