Neuroblastoma (NB) is the most common type of extracranial solid tumor found in children. Despite several treatment options, patients with advanced stage disease have a poor prognosis. Previous studies have reported that enhancer of zeste homolog 2 (EZH2) and long non-coding RNAs (lncRNAs) have abnormal expression levels in NB and participate in tumorigenesis and NB development. However, the association between EZH2 and lncRNAs remain unclear. In the present study, RNA immunoprecipitation-sequencing (RIP-seq) was used to analyze the lncRNAs binding to EZH2. Following EZH2 knockdown via short hairpin RNA, RNA-seq was performed in shEZH2 and control groups in SH-SY5Y cells. Chromatin IP (ChIP)-seq was used to determine the genes that may be regulated by EZH2. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses were performed to identify the signaling pathways involved in NB. The results from RIP-seq identified 94 lncRNAs, including SNHG7, SNHG22, KTN-AS1 and Linc00843. Furthermore, results from RNA-seq demonstrated that, following EZH2 knockdown, 448 genes were up-and 571 genes were downregulated, with 32 lncRNAs up-and 35 downregulated and differentially expressed compared with control groups. Certain lncRNAs, including MALAT1, H19, Linc01021 and SNHG5, were differentially expressed in EZH2-knockdown group compared with the control group. ChIP-seq identified EZH2 located in the promoter region of 138 lncRNAs including CASC16, CASC15, LINC00694 and TBX5-AS1. In summary, the present study demonstrated that certain lncRNAs directly bound EZH2 and regulated EZH2 expression levels. A number of these lncRNAs that are associated with EZH2 may participate in NB tumorigenesis.

Increasing evidence has indicated that long noncoding RNAs (lncRNAs) play various important roles in the development of cancers. The widespread applications of ribosome profiling and ribosome nascent chain complex sequencing revealed that some short open reading frames of lncRNAs have micropeptide-coding potential. The resulting micropeptides have been shown to participate in N6-methyladenosine modification, tumor angiogenesis, cancer metabolism, and signal transduction. This review summarizes current information regarding the reported roles of lncRNA-encoded micropeptides in cancer, and explores the potential clinical value of these micropeptides in the development of anti-cancer drugs and prognostic tumor biomarkers.

Modification of m6A, as the most abundant mRNA modification, plays diverse roles in various biological processes in eukaryotes. Emerging evidence has revealed that m6A modification is closely associated with the activation and inhibition of tumor pathways, and it is significantly linked to the prognosis of cancer patients. Aberrant reduction or elevated expression of m6A regulators and of m6A itself have been identified in numerous tumors. In this review, we give a description of the dynamic properties of m6A modification regulators, such as methyltransferases, demethylases, and m6A binding proteins, and indicate the value of the balance between these proteins in regulating the expression of diverse genes and the underlying effects on cancer development. Furthermore, we summarize the “dual-edged weapon” role of RNA methylation in tumor progression and discuss that RNA methylation can not only result in tumorigenesis but also lead to suppression of tumor formation. In addition, we summarize the latest research progress on small-molecule targeting of m6A regulators to inhibit or activate m6A. These studies indicate that restoring the balance of m6A modification via targeting specific imbalanced regulators may be a novel anti-cancer strategy.

Our previous studies demonstrated that MEG3 was significantly downregulated in neuroblastoma (NB) and its expression was negatively associated with the INSS stage. Overexpression of MEG3 promoted apoptosis and inhibited proliferation in NB cells. In this study, we discovered more potential functions and molecular mechanisms of MEG3 in NB. According to the database, MEG3 positively correlated with the NB survival rate and was negatively associated with malignant clinical features. Moreover, we determined that MEG3 was mainly located in the nucleus by nuclear-cytoplasmic separation and RNA fish assays. Upregulation of MEG3 in stably transfected cell lines was accomplished, and CCK8, colony formation, and EDU assays were performed, which indicated that MEG3 significantly suppressed cell proliferation. Both wound healing and transwell experiments demonstrated that MEG3 decreased cell migration and invasion. CHIRP enrichments showed the anticancer effects of MEG3 were probably linked to autophagy and the mTOR signaling pathway. LC3 fluorescence dots and western blots showed that MEG3 attenuated autophagy by inhibiting FOXO1, but not the mTOR signaling pathway. Furthermore, MEG3 inhibited metastasis through epithelial-mesenchymal transition via the mTOR signaling pathway. Consistent with the above results, downregulation of MEG3 facilitated NB malignant phenotypes. Mechanistically, MEG3 and EZH2 regulated each other via a negative feedback loop and promoted NB progression together. In conclusion, our findings suggested that MEG3 was a tumor suppressor in NB and could be a potential target for NB treatment in the future.

Neuroblastoma (NB), an embryonic tumour originating from sympathetic crest cells, is the most common extracranial solid tumour type in children with poor overall prognosis. Accumulating evidence has demonstrated the involvement of long non-coding RNA (lncRNA) in numerous biological processes and their associations with embryonic development and multiple diseases. Ectopic lncRNA expression is linked to malignant tumours. Previous studies by our team indicate that MEG3 attenuates NB autophagy through inhibition of FOXO1 and epithelial-mesenchymal transition via the mTOR pathway in vitro. Moreover, MEG3 and EZH2 negatively regulate each other. In present study, we first collected 60 NB tissues and 20 adjacent tissues for Quantitative real-time polymerase chain reaction (Q-PCR) experiments and performed clinical correlation analysis of the results. At the same time, nude mice were used for subcutaneous tumour formation to detect the effect of MEG3 in vivo. Two NB cell lines, SK-N-AS and SK-N-BE(2)C, were overexpressed MEG3 and rescued with EZH2 and then were subjected to proliferation, migration, invasion, apoptosis and autophagy experiments. RNA-binding protein immunoprecipitation (RIP) and Co-Immunoprecipitation (Co-IP) experiments were performed to explore the molecular mechanism of MEG3 and EZH2 interaction. Q-PCR revealed that MEG3 expression was negatively correlated with INSS stage and risk grade of NB. Moreover, MEG3 overexpression was associated with inhibition of NB growth in vivo. MEG3 exerted an anti-cancer effect via stimulatory effects on EZH2 ubiquitination leading to its degradation. Conversely,

Previous research from our group revealed that the long coding RNA (lncRNA) linc01105 is associated with neuroblastoma proliferation and apoptosis, and that its expression is correlated with the International Neuroblastoma Staging System stage. The purpose of the present study was to investigate the functions of Linc01105 in neuroblastoma. Lentivirus-mediated linc01105 knockdown was performed in the neuroblastoma cell line SH-SY5Y. The expression levels of linc01105 and of other associated genes were measured by reverse transcription-quantitative PCR. Cell Counting Kit-8 assay and flow cytometry were used to determine cell viability and apoptosis. The levels of proteins were detected using western blot analysis. Bioinformatics analysis and luciferase reporter assays were used to examine the relationship between linc01105, miR-6769b-5p and vascular endothelial growth factor A (VEGFA). Angiogenesis ability was measured using a tube formation assay. The results demonstrated that HIF-1α overexpression promoted the transcription of linc01105 by acting as a transcription factor. Knockdown of linc01105 inhibited neuroblastoma cell proliferation, migration and invasion, and it induced apoptosis. In addition, linc01105 affected the expression of p53 and Bcl-2 family proteins and activated the caspase signaling pathway. Further functional experiments revealed that linc01105 promoted the expression of the miR-6769b-5p target gene VEGFA by acting as a sponge of miR-6769b-5p. In conclusion, linc01105 may contribute to neuroblastoma tumorigenesis and development. The present findings indicated that the interplay between the p53/caspase pathway and the linc01105/miR-6769b-5p/VEGFA axis may have important roles in the development of neuroblastoma.

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Non-syndromic cleft lip and palate (NSCLP) is one of the most common congenital malformations with multifactorial etiology. Although long non-coding RNAs (lncRNAs) have been implicated in the development of lip and palate, their roles in NSCLP are not fully elucidated. This study aimed to investigate how dysregulated lncRNAs contribute to NSCLP. Using lncRNA sequencing, bioinformatics analysis, and clinical tissue sample detection, we identified that lncRNA ZFAS1 was significantly upregulated in NSCLP. The upregulation of ZFAS1 mediated by SP1 transcription factor (SP1) inhibited expression levels of Wnt family member 4 (WNT4) through the binding with CCCTC-binding factor (CTCF), subsequently inactivating the WNT/β-catenin signaling pathway, which has been reported to play a significant role on the development of lip and palate. Moreover, in vitro, the overexpression of ZFAS1 inhibited cell proliferation and migration in human oral keratinocytes and human umbilical cord mesenchymal stem cells (HUC-MSCs) and also repressed chondrogenic differentiation of HUC-MSCs. In vivo, ZFAS1 suppressed cell proliferation and numbers of chondrocyte in the zebrafish ethmoid plate. In summary, these results indicated that ZFAS1 may be involved in NSCLP by affecting cell proliferation, migration, and chondrogenic differentiation through inactivating the WNT/β-catenin signaling pathway.