Integrated bioinformatics analysis of chromatin regulator EZH2 in regulating mRNA and lncRNA expression by ChIP sequencing and RNA sequencing

Regulatory role of non-coding RNA in ginseng rusty root symptom tissue

Ginseng rusty root symptom (GRS) is one of the primary diseases of ginseng. It leads to a severe decline in the quality of ginseng and significantly affects the ginseng industry. The regulatory mechanism of non-coding RNA (ncRNA) remains unclear in the course of disease. This study explored the long ncRNAs (lncRNAs), circular RNAs (circRNAs), and microRNAs (miRNAs) in GRS tissues and healthy ginseng (HG) tissues and performed functional enrichment analysis of the screened differentially expressed ncRNAs. Considering the predictive and regulatory effects of ncRNAs on mRNAs, we integrated ncRNA and mRNA data to analyze and construct relevant regulatory networks. A total of 17,645 lncRNAs, 245 circRNAs, and 299 miRNAs were obtained from HG and GRS samples, and the obtained ncRNAs were characterized, including the classification of lncRNAs, length and distribution of circRNA, and the length and family affiliations of miRNAs. In the analysis of differentially expressed ncRNA target genes, we found that lncRNAs may be involved in the homeostatic process of ginseng tissues and that lncRNAs, circRNAs, and miRNAs are involved in fatty acid-related regulation, suggesting that alterations in fatty acid-related pathways may play a key role in GRS. Besides, differentially expressed ncRNAs play an essential role in regulating transcriptional translation processes, primary metabolism such as starch and sucrose, and secondary metabolism such as alkaloids in ginseng tissues. Finally, we integrated the correlations between ncRNAs and mRNAs, constructed corresponding interaction networks, and identified ncRNAs that may play critical roles in GRS. These results provide a basis for revealing GRS's molecular mechanism and enrich our understanding of ncRNAs in ginseng.

Long non-coding RNA DIO3OS/let-7d/NF-κB2 axis regulates cells proliferation and metastasis of thyroid cancer cells

Due to the steadily rising morbidity and mortality, thyroid cancer remains the most commonly seen endocrine cancer. The present study attempted to investigate the mechanism from the perspective of long non-coding RNA (lncRNA) regulation. We identified 53 markedly increased lncRNAs in thyroid cancer samples according to TCGA data. Among them, high lncRNA DIO3OS expression was a risk factor for thyroid cancer patients' poorer overall survival. DIO3OS showed to be considerably increased within thyroid cancer tissue samples and cells. Knocking down DIO3OS within thyroid carcinoma cells suppressed cancer cell viability, the capacity of DNA synthesis, cell invasion, as well as cell migration; besides, proliferating markers, ki-67 and PCNA, were decreased by DIO3OS knockdown. Cancer bioinformatics analysis suggested that NF-κB2 might be related to DIO3OS function in thyroid cancer carcinogenesis. NF-κB2 was positively correlated with DIO3OS, and DIO3OS knockdown decreased NF-κB2 protein levels. Knocking down NF-κB2 within thyroid carcinoma cells suppressed cancer cell viability, the capacity of DNA synthesis, cell invasion, cell migration, and the protein levels of proliferating markers. Let-7d directly targeted DIO3OS and NF-κB2; DIO3OS knockdown upregulated let-7d expression. The overexpression of let-7d suppressed cancer cell viability, the capacity of DNA synthesis, cell invasion, cell migration, as well as the protein levels of proliferating markers. Let-7d inhibition remarkably attenuated the functions of DIO3OS knockdown in NF-κB2 expression and thyroid cancer cell phenotype. In conclusion, DIO3OS/let-7d/NF-κB2 axis regulates the viability, DNA synthesis capacity, invasion, and migration of thyroid cancer cells. The clinical application of this axis needs further in vivo and clinical investigation.

Mice lacking uterine enhancer of zeste homolog 2 have transcriptomic changes associated with uterine epithelial proliferation

Enhancer of zeste homolog 2 (EZH2) is a histone methyltransferase that suppresses gene expression. Previously, we developed a conditional null model where EZH2 is knocked out in uterus. Deletion of uterine EZH2 increased proliferation of luminal and glandular epithelial cells. Herein, we used RNA-Seq in wild-type (WT) and EZH2 conditional knockout (Ezh2cKO) uteri to obtain mechanistic insights into the gene expression changes that underpin the pathogenesis observed in these mice. Ovariectomized adult Ezh2cKO mice were treated with vehicle (V) or 17β-estradiol (E2; 1 ng/g). Uteri were collected at postnatal day (PND) 75 for RNA-Seq or immunostaining for epithelial proliferation. Weighted gene coexpression network analysis was used to link uterine gene expression patterns and epithelial proliferation. In V-treated mice, 88 transcripts were differentially expressed (DEG) in Ezh2cKO mice, and Bmp5, Crabp2, Lgr5, and Sprr2f were upregulated. E2 treatment resulted in 40 DEG with Krt5, Krt15, Olig3, Crabp1, and Serpinb7 upregulated in Ezh2cKO compared with control mice. Transcript analysis relative to proliferation rates revealed two module eigengenes correlated with epithelial proliferation in WT V vs. Ezh2cKO V and WT E2 vs. Ezh2cKO E2 mice, with a positive relationship in the former and inverse in the latter. Notably, the ESR1, Wnt, and Hippo signaling pathways were among those functionally enriched in Ezh2cKO females. Current results reveal unique gene expression patterns in Ezh2cKO uterus and provide insight into how loss of this critical epigenetic regulator assumingly contributes to uterine abnormalities.

Transcriptome sequencing of lncRNA, miRNA, mRNA and interaction network constructing in coronary heart disease

BACKGROUND

Non-coding RNA has been shown to participate in numerous biological and pathological processes and has attracted increasing attention in recent years. Recent studies have demonstrated that long non-coding RNA and micro RNA can interact through various mechanisms to regulate mRNA. Yet the gene-gene interaction has not been investigated in coronary heart disease (CHD).

METHODS

High throughput sequencing were used to identify differentially expressed (DE) lncRNA, miRNA, and mRNA profiles between CHD and healthy control. Gene Oncology (GO), KEGG enrichment analysis were performed. Gene-gene interaction network were constructed and pivotal genes were screened out. Lentivirus-induced shRNA infection and qRT-PCR were performed to validated the gene-gene interactions.

RESULTS

A total of 62 lncRNAs, 332 miRNAs and 366 mRNAs were differentially expressed between CHD and healthy control. GO and KEGG analysis show that immune related molecular mechanisms and biological processes play a role in CHD. The gene-gene interaction network were constructed and visualized based on Pearson correlation coefficients and starBase database. 6 miRNAs in the network were significantly correlated to left ventricular ejection fraction, total choleterol and homocysteine. 2 lncRNAs (CTA-384D8.35 and CTB-114C7.4 (refseq entry LOC100128059)), 1 miRNA (miR-4497), and 1 mRNA (NR4A1) were the pivotal genes. Lentivirus-induced shRNA infection and qRT-PCR had validated the pivotal gene-gene interactions.

CONCLUSIONS

These results have shown the potential of lncRNA, miRNA, and mRNA as clinical biomarkers and in elucidating pathological mechanisms of CHD from a transcriptomic perspective.

Nuclear division cycle 80 complex is associated with malignancy and predicts poor survival of hepatocellular carcinoma

The NDC80 (nuclear division cycle 80) complex takes part in chromosome segregation by forming an outer kinetochore and providing a platform for the interaction between chromosomes and microtubules, thus impacting the progression of mitosis and the cell cycle. The clinical significance of its components, NDC80, nuf2, spc24, and spc25, were widely explored in various malignancies respectively, yet seldom were they studied from the perspective of a complex. This paper explores the clinical importance of the NDC80 kinetochore complex components in terms of their expression level, prognostic value, and therapeutic potential in HCC (hepatocellular carcinoma) patients. With the data from several paired HCC samples from Nanfang Hospital, HCC patients from the TCGA database and other cases from GSE89377, we analyzed the expression levels of the NDC80 complex components, NDC80/nuf2/spc24/spc25, along with the survival data as well as other clinical features using statistical methods and GSEA. The study found that a high expression of NDC80 complex predicts poor survival, and these components have the potential to be used as therapeutic targets.

Systematic identification of lincRNA-based prognostic biomarkers by integrating lincRNA expression and copy number variation in lung adenocarcinoma

Copy number alterations (CNAs) of lincRNAs act as one of important mechanisms in disrupting lincRNA expression which may play critical roles during tumorigenesis in lung adenocarcinoma (LUAD). The copy number alterations of lincRNAs can mark the spectrum of cancer progression and may serve as biomarkers for prognosis in LUAD, however it is rarely studied. We analyzed RNASeq data for 488 LUAD patients from TCGA portal and 58 healthy subjects to identify prognostic lincRNAs predictive of patient survival. Computational analysis entailing integration of expression and copy number alteration data revealed five prognostic lincRNAs: RBPMS-AS1, TDRKH-AS1, LINC00578, RP11-470 M17.2 and LINC00941. The copy number alterations in the LINC00578 and RP11-470 M17.2 genes were positively associated with the longer overall survival of LUAD patients. The CNA in LINC00941 was negatively associated with the longer overall survival. Copy number amplification significantly correlated with increased expression of TDRKH-AS1, which regulates telomere organization and EZH2-mediated epigenetic silencing of CDKN1A, CDKN1B and IL24. Decreased survival of LUAD patients was associated with high LINC00941 expression. The LINC00941 regulates the PI3K-AKT signaling pathway, focal adhesion by influencing potential targets, such as KRAS proto-oncogene GTPase and VEGFC. These lincRNA-based prognostic biomarkers may destroy important cancer-related biological processes contributing to LUAD prognosis. In summary, we demonstrate the prognostic potential of four differentially expressed lincRNAs with copy number alterations (RBPMS-AS1, TDRKH-AS1, LINC00578 and RP11-470 M17.2) that are positively associated with longer overall survival of LUAD patients. One differentially expressed lincRNA LINC00941 with copy number alterations was negatively associated with longer overall survival of LUAD patients.