Expression Of Pluripotency-related Genes Research Articles

A Protocol for Detecting DNA Methylation Changes at CpG Sites of Stemness-Related Genes in Aging Stem Cells.

Aging adversely affects the self-renewal and differentiation capabilities of stem cells, which impairs tissue regeneration as well as the homeostasis. Epigenetic mechanisms, specifically DNA methylation, play a key role in the maintenance of pluripotency in stem cells and regulation of pluripotency-related gene expression. Age-related modifications in methylation patterns could influence the expression of genes critical for stem cell potency maintenance, including transcription factors Nanog and Sox2. The following chapter describes a step-by-step bisulfite sequencing protocol for detection of methylation changes in the aging stem cells and provides valuable insights into the stem cells epigenetic profile. Further, the methodology describes the steps of genomic DNA extraction, bisulfite conversion, real-time PCR amplification, and sequencing for an in-depth view of the epigenetic profile derived from aging stem cells.

O-215 Copper oxide nanoparticles (CuONPs) impairs mitophagy and promotes DNA methylation to suppress mouse embryonic pluripotency

Abstract Study question Does exposure to copper oxide nanoparticle (CuONPs) have adverse effects on early embryonic development? What is the potential mechanism? Summary answer CuONPs exposure can damage mitophagy and lead to α-KG reduction, resulting DNA hypermethylation, thereby reducing the pluripotency of pre-implantation embryos in mice. What is known already Environmental nanomaterials contamination is a great concern for organisms including human. Exposure to nanomaterials have been associated with fecundity and fertility in couples conceiving via assisted reproduction technology. Among these bio-effects, nanomaterials induced epigenetic changes are of particular interest. Copper oxide nanoparticles (CuONPs) are widely used in a huge range of applications which might pose potential risk to organisms. Recent studies reported that CuONPs exposure resulted in transgenerational toxicity in Caenorhabditis elegans associated with possible epigenetic regulation. However, whether CuONPs exposure affect mammalian embryonic development, and if so the underlying mechanisms, are unclear. Study design, size, duration For the human experiments, we measured the copper ion content in women’s urine, and assessed the expression of pluripotent genes in 3PN embryos treated with CuONPs. For the embryo experiments, we collected zygotes from ICR mice and cultured them in KSOM medium with CuONPs (10 μg/mL) until blastocyst stage. For the cell experiments, we treated mouse embryonic stem cells (mESCs) with CuONPs (2 μg/mL) for four days to detect cell proliferation and pluripotency. Participants/materials, setting, methods The ICP-MS method was used to detect copper ion content in women’s urine. Time–lapse incubator was used to document the developmental potential of embryos. To quantify the metabolites of embryo, we employed metabolomics. Single-cell multiomics sequencing that enables profiling of genome-wide chromatin accessibility, DNA methylation and RNA expression were performed to detect genes expression and epigenetic modification. We used real-time PCR, immunofluorescence, and western blot to measure the expression of pluripotency related genes. Main results and the role of chance In human, we discovered a significant negative relationship between the urine’s copper ion content and clinical pregnancy rate. In embryo experiments, CuONPs exposure has been shown to have adverse effects on embryo developmental potential, resulting morula and blastocyst transformation arrest, as well as reduction in blastocyst rate and live birth rate. Furthermore, CuONPs treatment led to a reduction in blastocyst quality, indicating a decrease in blastocyst cell count, particularly in ICM cells. CuONPs also inhibited the pluripotency of blastocysts and mESCs, showing down-regulated expression of pluripotent genes. Mechanistically, CuONPs aggregated in lysosomes and decreased the mitophagic flux of embryos, which caused damaged mitochondria to accumulate and ultimately caused mitochondrial dysfunction. Notably, in embryos treated with CuONPs, there was a decrease in α-ketoglutarate (α-KG) due to the disruption of the tricarboxylic acid (TCA) cycle. α-KG is an essential cofactor for α-KG dependent dioxygenases such as the ten-eleven translocation (TET) family of DNA demethylase. The lack of α-KG in CuONPs-treated embryos led to DNA hypermethylation, which reduced chromatin accessibility, and suppressed the expression of pluripotent genes like sox2, klf2, and klf4. The poor pluripotency ultimately leads to abnormal embryonic development in CuONPs-treated embryos. Limitations, reasons for caution The molecular mechanism by which CuONPs arrest the development of pre-implantation embryos remains to be determined. In addition, future work should be extended to human embryos to determine whether this mechanism is conserved between mice and humans. Wider implications of the findings The findings of this work indicated the relationship between CuONPs and epigenetic modification. The results will support a more thorough understanding into the biosafety of CuONPs, and offer fresh perspectives on the potential uses of nanomaterials in the field of reproductive medicine in the future. Trial registration number Not Applicable

DNA Methyltransferase Inhibition by RG108 Improves Stemness and Multipotential Differentiation of Human Adipose Tissue-derived Stem Cells.

DNA methylation plays important roles in regulating various biological processes, including self-renewal, differentiation and regenerative capacity of stem cells. Previous studies have demonstrated that lineage-specific differentiation of mesenchymal stem cells can be promoted using nontoxic chromatin-modifying drugs. Here we evaluated the impact of RG108, a known DNA methyltransferase inhibitor, on the expression of pluripotency genes in human adipose tissue-derived stem cells (hADSCs) and their proliferation and differentiation. Human ADSCs were isolated by collagenase treatment and characterized. Then, ADSCs were treated with 5 µM RG108 for four days. The control and RG108-treated cells were analyzed for the cell cycle progression, apoptosis and the expression of pluripotency genes. Also, ADSCs were cultured in adipogenic and osteogenic differentiation media for three weeks and were assessed by Oil Red O and Alizarin Red S staining and qPCR analysis. We showed that RG108 treatment increased proliferation of hADSCs and upregulated the expression of pluripotency-related genes. Additionally, RG108 had a positive impact on the differentiation capability of ADSCs. This was evident through elevated levels of Oil Red O staining in the RG108 treatment group. Also, qPCR analysis showed the upregulation of some adipogenic and osteogenic markers by RG108. These findings indicate that pretreatment with RG108 improves the differentiation potential of ADSCs, probably making these cells more beneficial for cell therapy applications.

Comparative study of pluripotency-related gene expression in Umbilical Cord Mesenchymal Stem Cells (UC-MSC) from IUGR, SGA and normally grown fetuses

Background and Objectives: Intrauterine growth restriction (IUGR) is worldwide a public health problem. IUGR-born individuals acquire epigenetic “thrifty-phenotype” gene adaptations, according to the “Barker hypothesis” and are more susceptible to develop metabolic related diseases. Small for Gestational Age (SGA) fetuses consist of a transitional group between IUGR and normally grown fetuses (Appropriate for Gestational Age, AGA). Currently, there is limited information in the literature whether IUGR or SGA status affects the pluripotency of the Umbilical Cord Mesenchymal Stem Cell (UC-MSC) with respect to gene expression at various stages of cell culture. Materials and Methods: In this study, we investigated stemness marker expression in UC-MSCs derived from twenty-one AGA, IUGR, and SGA fetuses. The relative expression of key genes involved in stemness, pluripotency, and cell proliferation, namely IGF2BP1, CMYC, GLI1, P21, NANOG, OCT4, and SOX2, was assessed in UC-MSCs at passages P0 and P1 using flow cytometry and quantitative PCR. Results: We found lower median expression levels of IGF2BP1 in IUGR group (P=0.044) and P21 in SGA group (P=0.024) at P0 compared to control group. GLI1 and OCT4 exhibited reduced expression at P1 in the IUGR group (P=0.0434 and P=0.0343 respectively) compared to AGA. NANOG median expression differed statistically between CONTROL and IUGR group in P0 (P=0.034) and P1 (P=0.0205). No significant changes were noted for SOX2 and CMYC median expression among the various groups in P0 and P1. Conclusion: The comparative analysis of stemness marker expression among UC-MSCs from these three different sources is a novel descriptive aspect of our study, adding a new perspective to the existing literature.

BRG1 enhances porcine iPSC pluripotency through WNT/β-catenin and autophagy pathways

Brahma-related gene 1 (BRG1) enhances the pluripotency of embryonic and adult stem cells, however, its effect on induced pluripotent stem cell (iPSC) pluripotency has not been reported. The aim of this study was to investigate the effect of BRG1 on porcine iPSC pluripotency and its mechanisms. The effect of BRG1 on porcine iPSC pluripotency was explored by positive and negative control it. The mechanism was investigated by regulating the WNT/β-catenin signaling pathway and autophagy flux. The results showed that inhibition of BRG1 decreased pluripotency-related gene expression in porcine iPSCs; while its overexpression had the opposite effect, the expression of WNT/β-catenin signaling pathway- and autophagy-related genes was significantly up-regulated (P < 0.05) in the BRG1 overexpressed group when compared to the control group. Inhibited pluripotency-related gene or protein expression, decreased autophagy flux, and increased mitochondrial length and mitochondrial membrane potential (MMP) were observed when porcine iPSCs were treated with the WNT/β-catenin signaling pathway inhibitor IWR-1. Forced BRG1 expression restored porcine iPSC pluripotency, increased autophagy flux, shortened mitochondria, and reduced MMP. Lastly, Compound C was used to activate porcine iPSC autophagy, and it was found that the expression of BRG1 and β-catenin increased, and pluripotency-related gene and protein expression was up-regulated; these effects were reversed when the BRG1 inhibitor PFI-3 and IWR-1 were added. These results suggested that BRG1 enhanced the pluripotency of porcine iPSCs through WNT/β-catenin and autophagy pathways.

Chromatin analysis of adult pluripotent stem cells reveals a unique stemness maintenance strategy.

Many highly regenerative organisms maintain adult pluripotent stem cells throughout their life, but how the long-term maintenance of pluripotency is accomplished is unclear. To decipher the regulatory logic of adult pluripotent stem cells, we analyzed the chromatin organization of stem cell genes in the planarian Schmidtea mediterranea. We identify a special chromatin state of stem cell genes, which is distinct from that of tissue-specific genes and resembles constitutive genes. Where tissue-specific promoters have detectable transcription factor binding sites, the promoters of stem cell-specific genes instead have sequence features that broadly decrease nucleosome binding affinity. This genic organization makes pluripotency-related gene expression the default state in these cells, which is maintained by the activity of chromatin remodelers ISWI and SNF2 in the stem cells.

Exogenous OCT4 and SOX2 Contribution to In Vitro Reprogramming in Cattle.

Mechanisms of cell reprogramming by pluripotency-related transcription factors or nuclear transfer seem to be mediated by similar pathways, and the study of the contribution of OCT4 and SOX2 in both processes may help elucidate the mechanisms responsible for pluripotency. Bovine fibroblasts expressing exogenous OCT4 or SOX2, or both, were analyzed regarding the expression of pluripotency factors and imprinted genes H19 and IGF2R, and used for in vitro reprogramming. The expression of the H19 gene was increased in the control sorted group, and putative iPSC-like cells were obtained when cells were not submitted to cell sorting. When sorted cells expressing OCT4, SOX2, or none (control) were used as donor cells for somatic cell nuclear transfer, fusion rates were 60.0% vs. 64.95% and 70.53% vs. 67.24% for SOX2 vs. control and OCT4 vs. control groups, respectively; cleavage rates were 66.66% vs. 81.68% and 86.47% vs. 85.18%, respectively; blastocyst rates were 33.05% vs. 44.15% and 52.06% vs. 44.78%, respectively. These results show that the production of embryos by NT resulted in similar rates of in vitro developmental competence compared to control cells regardless of different profiles of pluripotency-related gene expression presented by donor cells; however, induced reprogramming was compromised after cell sorting.

Network characterization linc1393 in the maintenance of pluripotency provides the principles for lncRNA targets prediction

Long non-coding RNAs (lncRNAs) have been implicated in diverse biological processes. However, the functional mechanisms have not yet been fully explored. Characterizing the interactions of lncRNAs with chromatin is central to determining their functions but, due to precise and efficient approaches lacking, our understanding of their functional mechanisms has progressed slowly. In this study, we demonstrate that a nuclear lncRNA linc1393 maintains mouse ESC pluripotency by recruiting SET1A near its binding sites, to establish H3K4me3 status and activate the expression of specific pluripotency-related genes. Moreover, we characterized the principles of lncRNA-chromatin interaction and transcriptional regulation. Accordingly, we developed a computational framework based on the XGBoost model, LncTargeter, to predict the targets of a given lncRNA, and validated its reliability in various cellular contexts. Together, these findings elucidate the roles and mechanisms of lncRNA on pluripotency maintenance, and provide a promising tool for predicting the regulatory networks of lncRNAs.

High Nutritional Quality of Human-Induced Pluripotent Stem Cell-Generated Proteins through an Advanced Scalable Peptide Hydrogel 3D Suspension System.

Cell-cultured protein technology has become increasingly attractive due to its sustainability and climate benefits. The aim of this study is to determine the nutritional quality of the human-induced pluripotent stem cell (hiPSC)-cultured proteins in an advanced 3D peptide hydrogel system for the highly efficient production of cell-cultured proteins. Our previous study demonstrated a PGmatrix peptide hydrogel for the 3D embedded culture of long-term hiPSC maintenance and expansion (PGmatrix-hiPSC (PG-3D)), which showed significantly superior pluripotency when compared with traditional 2D cell culture on Matrigel and/or Vitronectin and other existing 3D scaffolding systems such as Polyethylene glycol (PEG)-based hydrogels. In this study, we designed a PGmatrix 3D suspension (PG-3DSUSP) system from the PG-3D embedded system that allows scaling up a hiPSC 3D culture volume by 20 times (e.g., from 0.5 mL to 10 mL). The results indicated that the PG-3DSUSP was a competitive system compared to the well-established PG-3D embedded method in terms of cell growth performance and cell pluripotency. hiPSCs cultured in PG-3DSUSP consistently presented a 15-20-fold increase in growth and a 95-99% increase in viability across multiple passages with spheroids with a size range of 30-50 μm. The expression of pluripotency-related genes, including NANOG, OCT4, hTERT, REX1, and UTF1, in PG-3DSUSP-cultured hiPSCs was similar to or higher than that observed in a PG-3D system, suggesting continuous pluripotent maintenance. The nutritional value of the hiPSC-generated proteins from the PG-3DSUSP system was further evaluated for amino acid composition and in vitro protein digestibility. The amino acid composition of the hiPSC-generated proteins demonstrated a significantly higher essential amino acid content (39.0%) than human skeletal muscle protein (31.8%). In vitro protein digestibility of hiPSC-generated proteins was significantly higher (78.0 ± 0.7%) than that of the commercial beef protein isolate (75.7 ± 0.6%). Taken together, this is the first study to report an advanced PG-3DSUSP culture system to produce highly efficient hiPSC-generated proteins that possess more essential amino acids and better digestibility. The hiPSC-generated proteins with superior nutrition quality may be of particular significance as novel alternative proteins in food engineering and industries for future food, beverage, and supplement applications.

Generation of the induced pluripotent stem cell line SFMUi001-A from a patient with usher syndrome type 2 caused by biallelic variants in the USH2A gene

Biallelic variants in the USH2A gene cause Usher syndrome type 2 (USH2), in which patients’ symptoms are progressive night blindness, reduced visual field, decreased central vision and sensorineural hearing impairment. There is currently no effective drug for USH2. In this study, we isolated peripheral blood mononuclear cells from a patient with USH2. The pluripotency of induced cells was verified by the presence of cell surface markers, the expression of pluripotent genes, and the formation of teratomas. The generation of this induced pluripotent stem cell line provides an effective way to study USH2, such as disease modeling and drug screening.Usher syndrome type 2 (USH2) is a genetic disease mainly caused by biallelic variants in the USH2A gene. Patients usually present with progressive night blindness, reduced visual field, and then reduced central vision. Patients with USH2 also have sensorineural hearing impairment. There is currently no effective treatment for USH2, and the pathogenesis is still unclear. Therefore, it is of great significance to study the pathogenic mechanism of USH2A gene variants for the study of therapeutic targets. In this study, we obtained induced pluripotent stem cell (iPSC) line containing USH2A gene variants. We isolated mononuclear cells from the peripheral blood of patient and established iPSCs by reprogramming with nonintegrating vectors. We then confirmed the pluripotency of our generated iPSCs through the detection of multiple cell surface markers, the expression of pluripotency-related genes, and the ability to form teratomas with three germ layer structures in vivo. The generation of this cell line will facilitate research on USH2 disease and will play a role that cannot be underestimated in future organoid generation, drug screening, and research on drug targets as well as mechanisms.

Feeder cell-dependent primary culture of single blastula-derived embryonic cell lines from marine medaka (Oryzias dancena).

Fish embryonic stem cells (ESCs) are derived from blastomeres that have been cultured from blastula embryos. The most widely used method for derivation of fish ESCs is the culture of blastomeres that have been isolated from approximately 10 blastula embryos under feeder-free conditions. However, this method leads to intercellular genetic heterogeneity among the cultured cells, which is a major obstacle to the development of stable ESC culture conditions. In this study, to establish ESC lines with intercellular genetic homogeneity at the early stage of culture, we attempted to derive embryonic cell lines from single blastula-derived blastomeres of marine medaka (Oryzias dancena) in a feeder cell culture system. Using basic fibroblast growth factor-expressing feeder cells during primary culture, we successfully established 22 single blastula-derived embryonic cell lines that could be subcultured more than 20 times. In contrast, we were unable to efficiently derive cell lines using wild-type feeder cells and under feeder-free conditions. The established cell lines exhibited ESC-like cell characteristics in terms of alkaline phosphatase activity, pluripotency-related gene expression, and embryoid body formation. The results of this study will contribute to the development of methods for derivation of fish ESCs.

Optimization of bovine embryonic fibroblast feeder layer prepared by Mitomycin C.

Feeder cells play important roles in In-vitro culture of stem cells. However, the preparation protocol of feeder cells produced by bovine embryonic fibroblast cells (bEFs) is still lack. In this study, the preparation of bEF-feeder by Mitomycin C was optimized with different concentrations and treatment time. The cell viability of bEFs was detected by CCK8 and 5-Ethynyl-2'-deoxyuridine. The growth of bESCs in each bEFs-feeder group was assessed by alkaline phosphatase staining and CCK8. Quantitative real time PCR was used to detect the mRNA expression of pluripotency-related genes of bESCs. Results showed that the proliferation of bEFs was significantly repressed while bEFs were treated with 14 ug/mL or 16 ug/mL Mitomycin C for 3h, and the cell viability within 2-4days after treatment was consistent with the 1st day. The numbers of bESCs clones in bEF-feeder treated with 14μg/mL Mitomycin C for 3h or 16μg/mL Mitomycin C for 3h were significantly higher than that in bEF-feeder treated with 8μg/mL Mitomycin C for 8h or bEFs treated with 6μg/mL Mitomycin C for 9h. The mRNA expression of pluripotency-related genes in bESCs cultured by bEF-feeder were higher than the MEF-feeder, the clone morphology of bESCs cultured in bEF-feeder was rounder and sharper than the MEF-feeder. In conclusion, the bEF-feeder prepared with 14μg/mL Mitomycin C for 3h or 16μg/mL Mitomycin C for 3h could effectively maintains the growth of bESCs, and bEF-feeder is more suitable for bESCs culture than the MEF-feeder.

Ten-Eleven Translocation-3 CXXC domain is critical for postfertilization demethylation and expression of pluripotency genes in pig embryos†.

Enzymes of the ten-eleven translocation family are considered to play an important role in the regulation of DNA methylation patterns by converting 5-methylcytosine to 5-hydroxymethylcytosine. Known as a maternal transcript enriched in mature oocytes, ten-eleven translocation-3 (TET3) has been suggested to initiate DNA demethylation of the paternal genome in zygotes. Previous studies in mouse cells indicate that the N-terminal CXXC domain of TET3 is important in catalyzing the oxidation of 5-methylcytosine through its potential DNA binding ability; however, it is not clear whether the DNA binding capacity of CXXC domain is required for the 5-hydroxymethylcytosine conversion in mammalian embryos. Here, we identified TET3 isoforms in porcine oocytes and investigated the role of the oocyte specific TET3 isoform (pTET3L) in controlling postfertilization demethylation in porcine embryos. The pTET3L possessed sequences representing a known DNA binding domain, the CXXC, and injection of the TET3 CXXC fused with GFP into mature porcine oocytes resulted in exclusive localization of the GFP-CXXC in the pronuclei. The CXXC overexpression reduced the 5-methylcytosine level in zygotes and enhanced the DNA demethylation of the NANOG promoter in 2-cell stage embryos. Furthermore, there was an increase in the transcript abundance of NANOG and ESRRB in blastocysts developed from GFP-CXXC injected oocytes. Targeted knockdown of pTET3L resulted in the downregulation of pluripotency genes in subsequently developed blastocysts. The findings indicate that the CXXC domain of TET3 serves as a critical component for the postfertilization demethylation of porcine embryos and coordinates proper expression of pluripotency related genes in blastocysts.

Rapamycin Treatment Is Beneficial for the Generation of Rabbit-Induced Pluripotent Stem-Like Cells.

Autophagy could promote the generation of induced pluripotency stem cells (iPSCs) in humans and mice. However, little was known whether it had similar effects in other species, the detailed mechanism and the features of formed iPSC colonies were also not clear. In this study, we first established the doxycycline (DOX)-inducible tetO lentiviral vector system suitable for the generation of rabbit iPSCs. Rapamycin, a mechanistic target of rapamycin (mTOR) inhibitor, was added during rabbit embryonic fibroblasts induction to improve the autophagy level. The colony formation efficiency and the expression of autophagy- and pluripotent-related genes were detected. The results showed that the established DOX-inducible tetO lentiviral system was successfully used to induce rabbit iPS-like cells. Compared with the untreated group, the number of alkaline phosphatase (AP)-positive colonies was increased 5.5-fold, when 0.5 nM rapamycin was added on days 1-3 after transduction, the colony morphology was improved and the iPS-like cells could be passaged >10 generations. The expression of autophagy-related genes (ATG), ATG5, ATG7, LC3, and ULK1 was increased with different patterns during the induction process, expression of OCT4, SOX2, and KLF4 significantly increased (p < 0.05). The mentioned results indicate that rapamycin treatment is beneficial for the generation of rabbit iPSCs by regulating autophagy and pluripotency-related gene expression.

Establishment of the induced pluripotent stem cell line PLAFMCi006-A from peripheral blood mononuclear cells of polycystic kidney disease patients with PKD2 gene mutation

Polycystic kidney disease (PKD) caused by PKD2 mutation is an important type of autosomal dominant PKD. In this study, peripheral blood mononuclear cells from a patient with PKD2 polycystic kidney disease were reprogrammed to obtain induced pluripotent stem cells (iPSCs). After stable amplification, the pluripotency of the iPSCs was determined by identifying their cell-surface markers, their expression of pluripotency-related genes, and their ability to form teratomas with three germ layers in vivo. The establishment of the iPSC line could provide a basis for a kidney-like organ model of human PKD caused by PKD2 mutation for use in studying the pathogenesis of PKD along with relevant screening and testing intervention drugs.

Increased expression of PD-L1 in endometrial cancer stem-like cells is regulated by hypoxia

Background: The expression levels of the programmed cell death ligand 1 (PD-L1), known as an immune-inhibitory molecule, are closely associated with cancer stem cell (CSCs) immune escape. Recently, PD-L1 has also been reported to be able to regulate the self-renewal of cancer stem cells. However, The expression and intrinsic role of PD-L1 in endometrial cancer stem-like cell (ECSC) maintenance and its underlying mechanism of action remain unclear. Methods: Using flow cytometry and western blot assays, we have demonstrated that PD-L1 expression is higher in ECSCs derived from endometrial cancer than in nonstem-like cancer cells. Using mouse xenograft assays for ECSC tumorigenicity. Using gene reporter assay for uncovering the regulation mechanism of PD-L1 in the hypoxia. Results: We revealed the high expression levels of PD-L1 in ECSCs and its correlation with self-renewal. We further found that PD-L1 knockdown reduced expression of several pluripotency-related genes (aldehyde dehydrogenase 1 (ALDH1), CD133, OCT4, SOX2, NANOG), impaired ECSC proliferation and undifferentiated colonies and decreased the number of CD133 positive ECSCs and the number of stem-like spheres. Furthermore, we found that PD-L1 knockdown inhibited ECSC tumorigenicity and the PD-L1 induced self-renewal capability of ECSCs was dependent upon hypoxia HIF-1α and HIF-2α activation. Conclusions: These data link ECSC maintenance to PD-L1 expression through hypoxia and suggest a promising target for PD1/PD-L1 immunotherapy.

Expression of pluripotency-related genes in human glioblastoma.

BackgroundCancer is a group of heterogeneous diseases characterized by several disruptions of the genetic and epigenetic components of cell biology. Some types of cancer have been shown to be constituted by a mosaic of cells with variable differentiation states, with more aggressive tumors being more undifferentiated. In most cases, undifferentiated tumor cells express associated embryonic markers such as the OCT4, NANOG, SOX2, and CARM1 genes. The ectopic or reminiscent expression of some master regulator genes of pluripotency has been indicated as the cause of the poorly differentiated state of tumors, and based on the evidence of some reports, can be used as a possible therapeutic target. Considering this information, a more detailed investigation of the expression of pluripotency-associated genes is necessary to evaluate the roles of these genes in the etiology of some tumors and their use targets of therapy.MethodsThe expression of four pluripotency-related genes was investigated (OCT4, NANOG, SOX2, and CARM1) in the most malignant primary human brain tumor, glioblastoma (GBM).Results and ConclusionThe results demonstrated a signature of OCT4/SOX2/CARM1 genes and a significant increase of CARM1 expression in GBM cases.

Generation of an induced pluripotent stem cell line from a compound heterozygous patient in TK2 gene

Autosomal recessive mutations in Thymidine kinase 2 (TK2) gene cause depletion and multiple deletions in mtDNA which normally lead to fatal and progressive neuromyopathy in infants and children. We have generated an induced pluripotent stem cell (iPSC) line by reprogramming fibroblasts derived from a patient carrying TK2 mutations. New iPSC line pluripotency was evaluated by verifying the expression of pluripotency-related genes and the in vitro differentiation into the three germ layers. This human-derived model will be useful for studying the pathogenic mechanisms triggered by these mutations and for testing therapies in cell types normally affected in patients.

Generation of an induced pluripotent stem cell line from an Ohtahara syndrome patient with the hemizygous mutation p.Q503Afs*28 (c.1507_1508del) in the ARX gene

Aristaless-related homeobox (ARX)-related disorders are recessive X-linked intellectual disability disorders. We encountered a patient with a hemizygous mutation (c.1507_1508del) showing intellectual disability, early-onset epileptic encephalopathy and Ohtahara syndrome. The patient had female genitals, but an XY karyotype. We established an induced pluripotent stem cell (iPSC) line from the peripheral blood mononuclear cells (PBMCs) of a six-month Chinese child with a hemizygous mutation (c.1507_1508del) in ARX. The PBMCs were reprogrammed with Sendai viral vectors. The iPSCs showed stable amplification, pluripotency-related gene expression, and trilineage differentiation potential. Karyotype analysis of the iPSCs showed 23 pairs of chromosomes with normal structure and sex chromosome is XY.

IRF-1 expressed in the inner cell mass of the porcine early blastocyst enhances the pluripotency of induced pluripotent stem cells

BackgroundDespite years of research, porcine-induced pluripotent stem cells (piPSCs) with germline chimeric capacity have not been established. Furthermore, the key transcription factors (TFs) defining the naïve state in piPSCs also remain elusive, even though TFs in the inner cell mass (ICM) are believed to be key molecular determinants of naïve pluripotency. In this study, interferon regulatory factor 1 (IRF-1) was screened to express higher in ICM than trophectoderm (TE). But the impact of IRF-1 on maintenance of pluripotency in piPSCs was not determined.MethodsTranscriptome profiles of the early ICM were analyzed to determine highly interconnected TFs. Cells carrying these TFs’ reporter were used to as donor cells for somatic cell nuclear transfer to detect expression patterns in blastocysts. Next, IRF1-Flag was overexpressed in DOX-hLIF-2i piPSCs and AP staining, qRT-PCR, and RNA-seq were conducted to examine the effect of IRF-1 on pluripotency. Then, the expression of IRF-1 in DOX-hLIF-2i piPSCs was labeled by GFP and qRT-PCR was conducted to determine the difference between GFP-positive and GFP-negative cells. Next, ChIP-Seq was conducted to identify genes target by IRF-1. Treatment with IL7 in wild-type piPSCs and STAT3 phosphorylation inhibitor in IRF-1 overexpressing piPSCs was conducted to confirm the roles of JAK-STAT3 signaling pathway in IRF-1’s regulation of pluripotency. Moreover, during reprogramming, IRF-1 was overexpressed and knocked down to determine the change of reprogramming efficiency.ResultsIRF-1 was screened to be expressed higher in porcine ICM than TE of d6~7 SCNT blastocysts. First, overexpression of IRF-1 in the piPSCs was observed to promote the morphology, AP staining, and expression profiles of pluripotency genes as would be expected when cells approach the naïve state. Genes, KEGG pathways, and GO terms related to the process of differentiation were also downregulated. Next, in the wild-type piPSCs, high-level fluorescence activated by the IRF-1 promoter was associated with higher expression of naïve related genes in piPSCs. Analysis by ChIP-Seq indicated that genes related to the JAK-STAT pathway, and expression of IL7 and STAT3 were activated by IRF-1. The inhibitor of STAT3 phosphorylation was observed could revert the expression of primed genes in IRF-1 overexpressing cells, but the addition of IL7 in culture medium had no apparent change in the cell morphology, AP staining results, or expression of pluripotency related genes. In addition, knockdown of IRF-1 during reprogramming appeared to reduce reprogramming efficiency, whereas overexpression exerted the converse effect.ConclusionThe IRF-1 expressed in the ICM of pigs’ early blastocyst enhances the pluripotency of piPSCs, in part through promoting the JAK-STAT pathway.