Long noncoding RNA CCDC144NL-AS1 knockdown induces naïve-like state conversion of human pluripotent stem cells.

BACKGROUND: Human naïve pluripotency state cells can be derived from direct isolation of inner cell mass or primed-to-naïve resetting of human embryonic stem cells (hESCs) through different combinations of transcription factors, small molecular inhibitors, and growth factors. Long noncoding RNAs (lncRNAs) have been identified to be crucial in diverse biological processes, including pluripotency regulatory circuit of mouse pluripotent stem cells (PSCs), but few are involved in human PSCs' regulation of pluripotency and naïve pluripotency derivation. This study initially planned to discover more lncRNAs possibly playing significant roles in the regulation of human PSCs' pluripotency, but accidently identified a lncRNA whose knockdown in human PSCs induced naïve-like pluripotency conversion. METHODS: Candidate lncRNAs tightly correlated with human pluripotency were screened from 55 RNA-seq data containing human ESC, human induced pluripotent stem cell (iPSC), and somatic tissue samples. Then loss-of-function experiments in human PSCs were performed to investigate the function of these candidate lncRNAs. The naïve-like pluripotency conversion caused by CCDC144NL-AS1 knockdown (KD) was characterized by quantitative real-time PCR, immunofluorescence staining, western blotting, differentiation of hESCs in vitro and in vivo, RNA-seq, and chromatin immunoprecipitation. Finally, the signaling pathways in CCDC144NL-AS1-KD human PSCs were examined through western blotting and analysis of RNA-seq data. RESULTS: The results indicated that knockdown of CCDC144NL-AS1 induces naïve-like state conversion of human PSCs in the absence of additional transcription factors or small molecular inhibitors. CCDC144NL-AS1-KD human PSCs reveal naïve-like pluripotency features, such as elevated expression of naïve pluripotency-associated genes, increased developmental capacity, analogous transcriptional profiles to human naïve PSCs, and global reduction of repressive chromatin modification marks. Furthermore, CCDC144NL-AS1-KD human PSCs display inhibition of MAPK (ERK), accumulation of active ß-catenin, and upregulation of some LIF/STAT3 target genes, and all of these are concordant with previously reported traits of human naïve PSCs. CONCLUSIONS: Our study unveils an unexpected role of a lncRNA, CCDC144NL-AS1, in the naïve-like state conversion of human PSCs, providing a new perspective to further understand the regulation process of human early pluripotency states conversion. It is suggested that CCDC144NL-AS1 can be potentially valuable for future research on deriving higher quality naïve state human PSCs and promoting their therapeutic applications.

Extensive profiling of circular RNAs and the potential regulatory role of circRNA-000284 in cell proliferation and invasion of cervical cancer via sponging miR-506.

Circular RNAs (circRNAs) are key regulators in the development and progression of human cancers, however its role in cervical cancer tumorigenesis is not well understood. The present study aims to investigate the expression profiles and potential modulation of circRNA on cervical cancer carcinogenesis. Human circRNA microarray was performed to screen for abnormally expressed circRNA in cervical cancer cells and circRNA-000284 was identified as one circRNA significantly upregulated in cervical cancer cells. Subsequent mechanistic investigations suggested that knockdown of circRNA-000284 suppressed cell proliferation and invasion, and caused G0/G1 phase cell cycle arrest. By performing anti-AGO2 RNA precipitation and luciferase reporter assay, we identified miR-506 as the circRNA-000284-associated miRNA. Furthermore, Snail-2 was identified as a direct target of miR-506, and circRNA-000284 could positively regulate the expression of Snail-2. Finally, the tumor promoting effect of circRNA-000284 was abolished by co-expression of miR-506 mimics or Snail-2 silencing vector. In conclusion, circRNA-000284 promotes cell proliferation and invasion in cervical cancer, and may serve as a promising therapeutic target for cervical cancer patients. Therefore, silence of circRNA-000284 could be a future direction to develop a novel treatment strategy.

A novel long noncoding RNA lnc158 promotes the differentiation of mouse neural precursor cells into oligodendrocytes by targeting nuclear factor-IB.

Long noncoding RNAs have been implicated in oligodendrocyte myelination and oligodendrocyte maturation, but their roles in normal oligodendrocyte differentiation are not fully defined. Here, we report a novel nonprotein-coding RNA, named lnc158, discovered in mouse oligodendrocytes identified in subependymal ventricular zone tissue by single-cell RNA sequencing. Lnc158 is an endogenous antisense transcript of nuclear factor-IB (NFIB) and complementary to 3' untranslated region of NFIB mRNA. NFIB is a member of the nuclear factor-I family and is essential in the development of many organs such as brains and lungs. We found that lnc158 transcripts serve a biological function by regulating the transcription level of the NFIB coding gene in neural stem cells. Overexpression of lnc158 increased the expression of NFIB mRNA and knockdown of lnc158 decreased the expression of NFIB mRNA, suggesting that NFIB is regulated positively by lnc158. Further analyses showed that overexpression of lnc158 in neural stem cells induced a modest increase in CNP, MBP, MAG, and OSP mRNA level, and enhanced induction of differentiation along the lineage of oligodendrocytes. These results together imply that lnc158 positively modulates the transcription level of NFIB mRNA, leading to the enhanced induction of oligodendrocytes.

IL­33 enhances glioma cell migration and invasion by upregulation of MMP2 and MMP9 via the ST2-NF-κB pathway.

As an important member of the interleukin (IL)-1 family, IL­33 plays a significant role in tumor progression. To explore this, we previously analyzed the association between IL­33 expression and the prognosis of patients with glioma. However, the function of the IL­33/ST2 axis in glioma remained unclear. In the present study, immunofluorescent staining results revealed that the expression levels of IL­33 and ST2 receptor in glioma tissues were higher than those in normal brain tissues. Invasion and migration assays demonstrated that IL­33 significantly increased glioma cell invasion and migration in vitro. Furthermore, knockdown of ST2 by siRNA attenuated the IL­33-induced increase in invasion and migration. In addition, ELISA results revealed that IL­33 upregulated the expression of matrix metalloproteinase (MMP)2 and MMP9. Western blot analysis results indicated that IL­33 stimulation increased the phosphorylation of nuclear factor-κB (NF-κB) in a time- and dose-dependent manner. Moreover, silencing of the NF-κB pathway by BAY 11­7082 resulted in the inhibition of IL­33-induced invasion and migration, as well as the downregulation of MMP2 and MMP9 production. These findings indicate that IL­33 may be involved in the process of glioma cell invasion and migration by upregulating MMP2 and MMP9 via the ST2-NF-κB signaling pathway. Thus, IL­33 may be a novel therapeutic target for glioma.