SP1-Mediated Upregulation of Long Noncoding RNA ZFAS1 Involved in Non-syndromic Cleft Lip and Palate via Inactivating WNT/β-Catenin Signaling Pathway

Profiling of Long Non-Coding RNAs in Auricular Cartilage of Patients with Isolated Microtia

Introduction: Microtia is the second most common maxillofacial birth defect worldwide. However, the involvement of long non-coding RNAs (lncRNAs) in isolated microtia is not well understood. This study aimed at identifying lncRNAs that regulate the expression of genes associated with isolated microtia. Methods: We used our microarray data to analyze the expression pattern of lncRNA in the auricular cartilage tissues from 10 patients diagnosed with isolated microtia, alongside 15 control subjects. Five lncRNAs were chosen for validation using real-time quantitative reverse transcription-polymerase chain reaction (qRT-PCR). Results: We identified 4651 differentially expressed lncRNAs in the auricular cartilage from patients with isolated microtia. By Gene Ontology/Kyoto Encyclopedia of Genes and Genomes pathway (GO/KEGG) analysis, we identified 27 differentially expressed genes enriched in pathways associated with microtia. In addition, we predicted 9 differentially expressed genes as potential cis-acting targets of 12 differentially expressed lncRNAs. Our findings by qRT-PCR demonstrate significantly elevated expression levels of ZFAS1 and DAB1-AS1, whereas ADIRF-AS1, HOTAIRM1, and EPB41L4A-AS1 exhibited significantly reduced expression levels in the auricular cartilage tissues of patients with isolated microtia. Conclusions: Our study sheds light on the potential involvement of lncRNAs in microtia and provides a basis for further investigation into their functional roles and underlying mechanisms.

Unveiling dysregulated lncRNAs and networks in non-syndromic cleft lip with or without cleft palate pathogenesis

Non-syndromic cleft lip with or without cleft palate (NSCL/P) is a common congenital facial malformation with a complex, incompletely understood origin. Long noncoding RNAs (lncRNAs) have emerged as pivotal regulators of gene expression, potentially shedding light on NSCL/P's etiology. This study aimed to identify critical lncRNAs and construct regulatory networks to unveil NSCL/P's underlying molecular mechanisms. Integrating gene expression profiles from the Gene Expression Omnibus (GEO) database, we pinpointed 30 dysregulated NSCL/P-associated lncRNAs. Subsequent analyses enabled the creation of competing endogenous RNA (ceRNA) networks, lncRNA-RNA binding protein (RBP) interaction networks, and lncRNA cis and trans regulation networks. RT-qPCR was used to examine the regulatory networks of lncRNA in vivo and in vitro. Furthermore, protein levels of lncRNA target genes were validated in human NSCL/P tissue samples and murine palatal shelves. Consequently, two lncRNAs and three mRNAs: FENDRR (log2FC = - 0.671, P = 0.040), TPT1-AS1 (log2FC = 0.854, P = 0.003), EIF3H (log2FC = - 1.081, P = 0.041), RBBP6 (log2FC = 0.914, P = 0.037), and SRSF1 (log2FC = 0.763, P = 0.026) emerged as potential contributors to NSCL/P pathogenesis. Functional enrichment analyses illuminated the biological functions and pathways associated with these lncRNA-related networks in NSCL/P. In summary, this study comprehensively delineates the dysregulated transcriptional landscape, identifies associated lncRNAs, and reveals pivotal sub-networks relevant to NSCL/P development, aiding our understanding of its molecular progression and setting the stage for further exploration of lncRNA and mRNA regulation in NSCL/P.

lncRNA MIR31HG Regulates Proliferation and Migration by Targeting Matrix Gla Protein in Nonsyndromic Cleft Lip With or Without Cleft Palate

Nonsyndromic cleft lip with or without cleft palate (NSCL/P) is a common craniofacial birth defect with complex etiologies. Recently, the dysregulation of long noncoding RNAs (lncRNAs) has been implicated in many developmental diseases, including NSCL/P. However, the functions and mechanisms of lncRNAs in NSCL/P have not been fully elucidated. In this study, we found that lncRNA MIR31HG in NSCL/P patients was significantly downregulated than that in healthy individuals (GSE42589, GSE183527). In addition, single nucleotide polymorphism rs58751040 in MIR31HG was nominally associated with NSCL/P susceptibility (odds ratio: 1.29, 95% confidence interval: 1.03-1.54, p = 4.93 × 10^-2) through a case-control study (504 NSCL/P cases and 455 controls). Luciferase activity assay showed that the C allele of rs58751040 revealed a decreased transcription activity of MIR31HG than the G allele. Moreover, knockdown of MIR31HG promoted cell proliferation and migration in human oral keratinocytes and human embryonic palate mesenchyme. Bioinformatic analysis and cellular studies suggested that MIR31HG may confer susceptibility to risk of NSCL/P through matrix Gla protein (MGP) signaling. In summary, we identified a novel lncRNA involved in the development of NSCL/P.

Identification of putative regulatory single-nucleotide variants in NTN1 gene associated with NSCL/P

Non-syndromic cleft lip with or without cleft palate (NSCL/P) is a common polygenetic disease. Although genome-wide association studies (GWAS) identified NTN1 gene as a high-priority candidate of NSCL/P, the comprehensive genetic architecture of NTN1 weren't yet known. Thus, this study aimed to determine full-scale genetic variants of NTN1 for NSCL/P in Chinese Han people. Initially, targeted sequencing of NTN1 gene was performed on 159 NSCL/P patients to identify susceptible single nucleotide polymorphisms (SNPs) associated with NSCL/P. Then, association analysis and burden analysis were separately used to validate the common variants and rare variants identified among large size of samples (1608 NSCL/P cases and 2255 controls). Additionally, NSCL/P subtype association analysis was applied to elucidate the etiology discrepancy of non-syndromic cleft lip with palate (NSCLP) and non-syndromic cleft lip only (NSCLO). Lastly, bioinformatics analysis was performed to annotate and prioritize candidate variants. We found 15 NSCL/P-associated SNPs including rs4791774 (P = 1.10E-08, OR = 1.467, 95% CI: 1.286~1.673) and rs9788972 (P = 1.28E-07, OR = 1.398, 95% CI : 1.235~1.584) originally detected by previous GWASs in Chinese Han ancestry. Four NSCLO risk-associated SNPs and eight specific NSCLP associated SNPs were found. Three SNPs (rs4791331, rs4791774 and rs9900753) were predicted to locate at regulatory region of NTN1. Our study validated the association between NTN1 gene and pathogenesis of NSCL/P and reinforced the hypothesis that NSCLP have a different etiology from NSCLO. We also identified three putative regulatory SNPs in NTN1 gene.

LINC01608 activated by YY1 facilitate hepatocellular carcinoma progression by modulating the EGFR/ERK axis

BACKGROUND

Long non-coding RNAs (LncRNAs) have been demonstrated to associate with a variety of cancers. However, the mechanisms of LncRNAs in hepatocellular carcinoma (HCC) progression are still not fully clarified.

METHODS

LINC01608 expression level in HCC and adjacent normal tissues was detected by real-time-quantitively PCR (RT-qPCR) in clinical samples and in situ hybridization (ISH) in tissue microarray. Several functional assays were performed to determine the biological effects of LINC01608 in HCC cells in vitro, while subcutaneous xenograft models and lung metastasis models in nude mice and immunohistochemistry (IHC) results showed the role of LINC01608 in HCC progression in vivo. The combination of LINC01608 with miR-875-5p and target genes was elucidated by dual-luciferase report assays, RNA immunoprecipitation (RIP) assays and fluorescence in situ hybridization (FISH) assays. Finally, bioinformatics analysis and chromatin immunoprecipitation (CHIP) were performed to investigate the mechanism of Yin Yang-1 (YY1) regulating LINC01608 transcription.

RESULTS

LINC01608 was overexpressed in HCC tissues, and high LINC01608 expression predicted poor overall survival (OS) and disease-free survival (DFS) in HCC patients. LINC01608 could promote HCC cell proliferation, migration, invasion and epithelial-mesenchymal transition (EMT) in vitro and in vivo. Furthermore, we demonstrated that LINC01608 could sponge to miR-875-5p and activate the EGFR/ERK pathway. Moreover, we identified transcriptional factor YY1 could bind to the promoter of LINC01608 and induce its transcription.

CONCLUSION

LINC01608 could serve as a promising prognostic biomarker of HCC. YY1-activated LINC01608 could promote HCC progression by associating with miR-875-5p to induce the EGFR/ERK signalling pathway. This discovery might provide therapeutic strategies for HCC.

Role of lncRNAs and circRNAs in Orofacial Clefts

Different modes of gene regulation, such as histone modification, transcription factor binding, DNA methylation, and microRNA (miRNA) expression, are critical for the spatiotemporal expression of genes in developing orofacial tissues. Aberrant regulation in any of these modes may contribute to orofacial defects. Noncoding RNAs (ncRNAs), such as long ncRNAs (lncRNAs) and circular RNAs (circRNAs), have been shown to alter miRNA expression, and are thus emerging as novel contributors to gene regulation. Some of these appear to function as 'miRNA sponges', thereby diminishing the availability of these miRNAs to inhibit the expression of target genes. Such ncRNAs are also termed competitive endogenous RNAs (ceRNAs). Here, we examine emerging data that shed light on how lncRNAs and circRNAs may alter miRNA regulation, thus affecting orofacial development and potentially contributing to orofacial clefting.

Application of zebrafish in the study of craniomaxillofacial developmental anomalies

Craniomaxillofacial developmental anomalies are one of the most prevalent congenital defects worldwide and could result from any disruption of normal development processes, which is generally influenced by interactions between genes and the environment. Currently, with the advances in genetic screening strategies, an increasing number of novel variants and their roles in orofacial diseases have been explored. Zebrafish is recognized as a powerful animal model, and its homologous genes and similar oral structure and development process provide an ideal platform for studying the contributions of genetic and environmental factors to human craniofacial malformations. Here, we reviewed zebrafish models for the study of craniomaxillofacial developmental anomalies, such as human nonsyndromic cleft lip with or without an affected palate and jaw and tooth developmental anomalies. Due to its potential for gene expression and regulation research, zebrafish may provide new perspectives for understanding craniomaxillofacial diseaseand its treatment.

Long Non-Coding RNAs MALAT1 and NEAT1 in Non-syndromic Orofacial Clefts

Long non-coding RNAs (lncRNAs) are thought to play important roles in non-syndromic orofacial clefts (NSOFC). Clinical diagnosis was categorized as either non-syndromic cleft lip with or without cleft palate (NSCL/P), or non-syndromic cleft palate-only (NSCPO). Tissues excised from the trimmed wound edge were reserved as experimental samples; adjacent normal control was used as a positive control, and tissue from healthy individuals was used as a blank control. Target lncRNAs in the collected tissues were identified using microarrays and quantitative reverse transcription PCR (RT-qPCR). Immunohistochemical (IHC) staining and RT-qPCR were used to verify the target mRNAs. Pathway, gene ontology (GO) enrichment, and TargetScan predictions were employed to construct competing endogenous RNA networks (ceRNA networks) and explore their potential functions. RNA-Seq revealed 24 upregulated and 43 downregulated lncRNAs; MALAT1 and NEAT1 were screened and validated using RT-qPCR. Common NSOFC risk factors were positively correlated with MALAT1 and NEAT1 expression. Bioinformatics predicted four ceRNA networks; GO enrichment focused on their potential functions. RT-qPCR and IHC data were consistent with respect to expression levels of proteins and the mRNAs that encode them. As MALAT1 and NEAT1 are associated with the severity of NSOFC, they represent potential therapeutic targets and prognostic biomarkers.