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Epigenetic silencing of miR-338 facilitates glioblastoma progression by de-repressing the pyruvate kinase M2-?-catenin axis.

ABSTRACT: Glioblastoma is the most malignant type of brain tumor, and its high invasiveness and multiplication severely shortens patients' overall survival. The embryonic pyruvate kinase M2 (PKM2) isoform is highly expressed in human cancer. We used computational target gene prediction, in vitro cell culture, immunoblotting, quantitative real-time PCR, ATP measurements, luciferase reporter assays, wound-healing assays, Transwell assays, RNA immunoprecipitation PCR, co-immunoprecipitation, flow cytometry and tumor xenografts to study the regulation of the PKM2/?-catenin axis in glioma. PKM2 was predicted to be a potential target of miR-338. MiR-338 was downregulated in high-grade gliomas due to hypermethylation of CpG islands in its promoter, and ectopic expression of miR-338 inhibited cell proliferation, invasion and ATP generation. MiR-338 inhibited PKM2 expression by binding to the 3' untranslated region of PKM2, which ultimately prevented binding of PKM2 to ?-catenin and reduced T-cell factor/lymphoid enhancer factor reporter gene transcriptional activity. MiR-338 also inhibited PKM2 expression, attenuated glioma growth and prolonged survival in an animal model. These results confirm that miR-338, a tumor suppressor, suppresses the PKM2/?-catenin axis and is downregulated in glioblastoma. This provides a theoretical basis for glioma-targeting therapy.

SUBMITTER: Han B

PROVIDER: S-EPMC5611983 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature

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Epigenetic silencing of miR-338 facilitates glioblastoma progression by de-repressing the pyruvate kinase M2-β-catenin axis.

Han Bo B Meng Xiangqi X Chen Hui H Chen Lingchao L Liu Xing X Wang Hongjun H Liu Daming D Gao Fei F Lin Lin L Ming Jianguang J Sun Bo B Yin Shi S Wang Ruijia R Wu Pengfei P Cai Jinquan J Jiang Chuanlu C

Aging 20170801 8

Glioblastoma is the most malignant type of brain tumor, and its high invasiveness and multiplication severely shortens patients' overall survival. The embryonic pyruvate kinase M2 (PKM2) isoform is highly expressed in human cancer. We used computational target gene prediction, <i>in vitro</i> cell culture, immunoblotting, quantitative real-time PCR, ATP measurements, luciferase reporter assays, wound-healing assays, Transwell assays, RNA immunoprecipitation PCR, co-immunoprecipitation, flow cyto ...[more]

PMID: 28858851

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Dataset Information

Epigenetic silencing of miR-338 facilitates glioblastoma progression by de-repressing the pyruvate kinase M2-?-catenin axis.

Publications

Epigenetic silencing of miR-338 facilitates glioblastoma progression by de-repressing the pyruvate kinase M2-β-catenin axis.

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