Dataset Information

MIAT Is an Upstream Regulator of NMYC and the Disruption of the MIAT/NMYC Axis Induces Cell Death in NMYC Amplified Neuroblastoma Cell Lines.

ABSTRACT: Neuroblastoma (NBL) is the most common extracranial childhood malignant tumor and represents a major cause of cancer-related deaths in infants. NMYC amplification or overexpression is associated with the malignant behavior of NBL tumors. In the present study, we revealed an association between long non-coding RNA (lncRNA) myocardial infarction associated transcript (MIAT) and NMYC amplification in NBL cell lines and MIAT expression in NBL tissue samples. MIAT silencing induces cell death only in cells with NMYC amplification, but in NBL cells without NMYC amplification it decreases only the proliferation. MIAT downregulation markedly reduces the NMYC expression in NMYC-amplified NBL cell lines and c-Myc expression in NMYC non-amplified NBL cell lines, but the ectopic overexpression or downregulation of NMYC did not affect the expression of MIAT. Moreover, MIAT downregulation results in decreased ornithine decarboxylase 1 (ODC1), a known transcriptional target of MYC oncogenes, and decreases the glycolytic metabolism and respiratory function. These results indicate that MIAT is an upstream regulator of NMYC and that MIAT/NMYC axis disruption induces cell death in NMYC-amplified NBL cell lines. These findings reveal a novel mechanism for the regulation of NMYC in NBL, suggesting that MIAT might be a potential therapeutic target, especially for those with NMYC amplification.

SUBMITTER: Feriancikova B

PROVIDER: S-EPMC8038079 | biostudies-literature | 2021 Mar

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

MIAT Is an Upstream Regulator of NMYC and the Disruption of the MIAT/NMYC Axis Induces Cell Death in NMYC Amplified Neuroblastoma Cell Lines.

Feriancikova Barbara B Feglarova Tereza T Krskova Lenka L Eckschlager Tomas T Vicha Ales A Hrabeta Jan J

International journal of molecular sciences 20210325 7

Neuroblastoma (NBL) is the most common extracranial childhood malignant tumor and represents a major cause of cancer-related deaths in infants. NMYC amplification or overexpression is associated with the malignant behavior of NBL tumors. In the present study, we revealed an association between long non-coding RNA (lncRNA) myocardial infarction associated transcript (MIAT) and NMYC amplification in NBL cell lines and MIAT expression in NBL tissue samples. MIAT silencing induces cell ...[more]

PMID: 33806217

Similar Datasets

Project description:Neuroblastoma derived from primitive sympathetic neural precursors is a common type of solid tumor in infants. MYCN proto‑oncogene bHLH transcription factor (MYCN) amplification and 1p36 deletion are important factors associated with the poor prognosis of neuroblastoma. Expression levels of MYCN and c‑MYB proto‑oncogene transcription factor (c‑myb) decline during the differentiation of neuroblastoma cells; E2F transcription factor 1 (E2F1) activates the MYCN promoter. However, the underlying mechanism of MYCN overexpression and amplification requires further investigation. In the present study, potential c‑Myb target genes, and the effect of c‑myb RNA interference (RNAi) on MYCN expression and amplification were investigated in MYCN‑amplified neuroblastoma cell lines. The mRNA expression levels and MYCN gene copy number in five neuroblastoma cell lines were determined by quantitative polymerase chain reaction. In addition, variations in potential target gene expression and MYCN gene copy number between pre‑ and post‑c‑myb RNAi treatment groups in MYCN‑amplified Kelly, IMR32, SIMA and MHH‑NB‑11 cell lines, normalized to those of non‑MYCN‑amplified SH‑SY5Y, were examined. To determine the associations between gene expression levels and chromosomal aberrations, MYCN amplification and 1p36 alterations in interphases/metaphases were analyzed using fluorescence in situ hybridization. Statistical analyses revealed correlations between 1p36 alterations and the expression of c‑myb, MYB proto‑oncogene like 2 (B‑myb) and cyclin dependent kinase inhibitor 1A (p21). Additionally, the results of the present study also demonstrated that c‑myb may be associated with E2F1 and L3MBTL1 histone methyl‑lysine binding protein (L3MBTL1) expression, and that E2F1 may contribute to MYCN, B‑myb, p21 and chromatin licensing and DNA replication factor 1 (hCdt1) expression, but to the repression of geminin (GMNN). On c‑myb RNAi treatment, L3MBTL1 expression was silenced, while GMNN was upregulated, indicating G2/M arrest. In addition, MYCN gene copy number increased following treatment with c‑myb RNAi. Notably, the present study also reported a 43.545% sequence identity between upstream of MYCN and Drosophila melanogaster amplification control element 3, suggesting that expression and/or amplification mechanisms of developmentally‑regulated genes may be evolutionarily conserved. In conclusion, c‑myb may be associated with regulating MYCN expression and amplification. c‑myb, B‑myb and p21 may also serve a role against chromosome 1p aberrations. Together, it was concluded that MYCN gene is amplified during S phase, potentially via a replication‑based mechanism.

Project description:BackgroundNeuroblastoma is responsible for 15% of all childhood cancer deaths. Despite advances in treatment and disease management, the overall 5-year survival rates remain poor in high-risk disease (25-40%). MiR-497 was previously identified by our laboratory as a member of a miRNA expression signature, predictive of neuroblastoma patient survival and has been reported as a tumor suppressor in a variety of other cancers. WEE1, a tyrosine kinase regulator of the cell cycle and predicted target of miR-497, has emerged as an oncogene in several cancer types and therefore represents an attractive potential target for novel therapy approaches in high-risk neuroblastoma. Our aim was to investigate the potential tumor suppressive role of miR-497 in high-risk neuroblastoma.MethodsExpression levels of miR-497 and WEE1 in tissues and cells were determined using RT-PCR. The effect of miR-497 and siWEE1 on cell viability was evaluated using MTS assays, apoptosis levels were determined using FACS analysis of Annexin V/PI stained cells, and target protein expression was determined using western blot. Luciferase reporter plasmids were constructed to confirm direct targeting. Results were reported as mean±S.E.M and differences were tested for significance using 2-tailed Students t-test.ResultsWe determined that miR-497 expression was significantly lower in high-risk MYCN amplified (MNA) tumors and that low miR-497 expression was associated with worse EFS and OS in our cohort. Over-expression of miR-497 reduced cell viability and increased apoptosis in MNA cells. We identified WEE1 as a novel target for miR-497 in neuroblastoma. Furthermore, our analysis showed that high WEE1 levels are significantly associated with poor EFS and OS in neuroblastoma and that siRNA knockdown of WEE1 in MNA cell lines results in significant levels of apoptosis, supporting an oncogenic role of WEE1 in neuroblastoma. Cisplatin (CDDP) treatment of both miR-497 over-expressing cells and WEE1 inhibited cells, resulted in a significant increase in apoptosis in MNA cells, describing a synergistic effect and therefore a potential therapeutic for high-risk neuroblastoma.ConclusionOur study's results are consistent with miR-497 being a candidate tumor suppressor in neuroblastoma, through the direct targeting of WEE1. These findings re-enforce the proposal of WEE1 as a therapeutic target in neuroblastoma.

Dataset Information

MIAT Is an Upstream Regulator of NMYC and the Disruption of the MIAT/NMYC Axis Induces Cell Death in NMYC Amplified Neuroblastoma Cell Lines.

Publications

MIAT Is an Upstream Regulator of NMYC and the Disruption of the MIAT/NMYC Axis Induces Cell Death in <i>NMYC</i> Amplified Neuroblastoma Cell Lines.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets