1. IGF-1-enhanced miR-513a-5p signaling desensitizes glioma cells to temozolomide by targeting the NEDD4L-inhibited Wnt/β-catenin pathway
- Author
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Kuo Hao Ho, Ku Chung Chen, Chwen Ming Shih, Chih Ming Chou, Chin Cheng Lee, Chia Hsiung Cheng, and Peng Hsu Chen
- Subjects
0301 basic medicine ,Microarrays ,Nedd4 Ubiquitin Protein Ligases ,Artificial Gene Amplification and Extension ,Biochemistry ,Polymerase Chain Reaction ,0302 clinical medicine ,Medicine and Health Sciences ,Blastomas ,Enzyme assays ,Colorimetric assays ,Insulin-Like Growth Factor I ,3' Untranslated Regions ,Wnt Signaling Pathway ,Neurological Tumors ,Bioassays and physiological analysis ,Regulation of gene expression ,Cultured Tumor Cells ,Multidisciplinary ,MTT assay ,Wnt signaling pathway ,Glioma ,Ubiquitin ligase ,Gene Expression Regulation, Neoplastic ,Nucleic acids ,Oncology ,Neurology ,030220 oncology & carcinogenesis ,Medicine ,Hyperexpression Techniques ,RNA Interference ,Biological Cultures ,medicine.drug ,Research Article ,Science ,Biology ,Research and Analysis Methods ,03 medical and health sciences ,Cell Line, Tumor ,microRNA ,medicine ,Temozolomide ,Genetics ,Gene Expression and Vector Techniques ,Humans ,Non-coding RNA ,Molecular Biology Techniques ,Molecular Biology ,PI3K/AKT/mTOR pathway ,Natural antisense transcripts ,Molecular Biology Assays and Analysis Techniques ,Biology and life sciences ,Cancers and Neoplasms ,Cell Cultures ,medicine.disease ,Glioma Cells ,Gene regulation ,MicroRNAs ,030104 developmental biology ,Drug Resistance, Neoplasm ,Catenin ,Biochemical analysis ,biology.protein ,Cancer research ,RNA ,Gene expression ,Glioblastoma Multiforme - Abstract
Temozolomide (TMZ) is a first-line alkylating agent for glioblastoma multiforme (GBM). Clarifying the mechanisms inducing TMZ insensitivity may be helpful in improving its therapeutic effectiveness against GBM. Insulin-like growth factor (IGF)-1 signaling and micro (mi)RNAs are relevant in mediating GBM progression. However, their roles in desensitizing GBM cells to TMZ are still unclear. We aimed to identify IGF-1-mediated miRNA regulatory networks that elicit TMZ insensitivity for GBM. IGF-1 treatment attenuated TMZ cytotoxicity via WNT/β-catenin signaling, but did not influence glioma cell growth. By miRNA array analyses, 93 upregulated and 148 downregulated miRNAs were identified in IGF-1-treated glioma cells. miR-513a-5p from the miR-513a-2 gene locus was upregulated by IGF-1-mediated phosphoinositide 3-kinase (PI3K) signaling. Its elevated levels were also observed in gliomas versus normal cells, in array data of The Cancer Genome Atlas (TCGA), and the GSE61710, GSE37366, and GSE41032 datasets. In addition, lower levels of neural precursor cell-expressed developmentally downregulated 4-like (NEDD4L), an E3 ubiquitin protein ligase that inhibits WNT signaling, were found in gliomas by analyzing cells, arrays, and RNA sequencing data of TCGA glioma patients. Furthermore, a negative correlation was identified between miR-513a-5p and NEDD4L in glioma. NEDD4L was also validated as a direct target gene of miR-513a-5p, and it was reduced by IGF-1 treatment. Overexpression of NEDD4L inhibited glioma cell viability and reversed IGF-1-repressed TMZ cytotoxicity. In contrast, miR-513a-5p significantly affected NEDD4L-inhibited WNT signaling and reduced TMZ cytotoxicity. These findings demonstrate a distinct role of IGF-1 signaling through miR-513a-5p-inhibited NEDD4L networks in influencing GBM's drug sensitivity to TMZ.
- Published
- 2019