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Objective: This study explored if human primary mesenchymal stem cells (MSCs), derived from two donors and cultivated in a medium made with intentionally treated water, would exhibit more growth and pluripotency than MSCs from the same source but grown in untreated (control) water.Design: To create the treated water, three Buddhist monks directed their attention toward commercially bottled water while holding the intention that the water would enhance the growth of MSCs. Under double-blind conditions, cell culture growth mediums were prepared with the treated and untreated water, which was in turn used to grow the primary MSCs. Primary cells obtained from two donors were designated as Cells #1 and Cells #2. The prediction was that treated water would result in increased cell proliferation, that more cells would enter the cell cycle growth phase, and that there would be increased expression of genes (NANOG, OCT4 and SOX2) associated with improved cell growth and decreased expression of genes (p16, p21, and p53) associated with a decline in cell growth. The improved growth hypothesis was directional, thus one-tailed p-values were used to evaluate the results.Results: Proliferation averaged across Cells #1 and #2 showed overall increased growth in treated as compared to control water (p = 0.0008). Cells #1 and #2 considered separately had differences in the same direction but only Cells #2 showed a significant difference on day 6 (p = 0.01). For cell cycle, there was a significantly greater percentage of Cells #2 in the S interphase with treated vs. control water (p = 0.04). For the gene expression analysis, when considering the average across the two donor cells, only the NANOG gene expression was in the predicted direction (p = 0.01); by contrast, the p16 gene expression was significantly opposite to the predicted direction (p = 0.005, one-tailed, post-hoc). For Cells #1 considered separately, no differences were significant except for p16, which resulted in an effect opposite to the predicted outcome (p = 0.05). For Cells #2, three genes were significantly in the predicted directions: NANOG (p = 0.0008), OCT4 (p = 0.005), and P53 (p = 0.05); p16 was significantly opposite to the prediction (p = 0.001).Conclusion: Intentionally treated water appeared to have some biological effects on the growth, pluripotency and senescence of human MSCs. This was especially the case in one of the two donor cells tested, but the effects were not consistently in the predicted direction. As an exploratory study, caution is warranted in interpreting these outcomes, and adjustment for multiple testing would likely reduce some of the weaker effects to nonsignificant. But given the double-blind protocol, as well as several more significant outcomes in the predicted directions, further research is warranted. [ABSTRACT FROM AUTHOR]

Nicotine, a pharmacological active and addictive substance of tobacco, widely used as through smoking. The detrimental effects of nicotine on male reproductive system have been researched, but the underlying exact molecular mechanism are not clearly unknown. In the current study, we aimed to investigate the effects of nicotine exposure on spermatogonial stem cells in mice. Twenty-four C57BL/6J mice were randomly divided into control (no treatment applied), sham (via subcutaneous injection, 9% saline) and nicotine (via subcutaneous injection, 3 mg/kg) group. The subcutaneous injections were performed twice daily (08:00 am, 12:00 pm), for 14 days. After administration period, blood samples were collected by cardiac puncture and analysed ELISA method for quantified serum cotinine (a major metabolite of nicotine) level. The right and left testicular tissues were isolated and performed to histological, immunohistochemical and molecular analysis. Immunohistochemical and quantitative real time polymerase chain reaction methods were performed to evaluate the expression level of OCT4, GDNF and STRA8 proteins and genes in testicular tissues. Light microscobic analysis were performed to assessment of seminiferous tubule histology and immunostaining intensity. The nicotine-treated group showed significantly morphological alterations of the seminiferous tubule. Serum cotinine level was measured as 303.34±0.8 ng/mL in nicotine-treated group. Also, nicotine caused significantly decreased in the protein and mRNA expression levels of OCT4, GDNF and STRA8. In conclusion, these findings thought that would shed light on both spermatogonial differentiation studies and pathogenesis mechanisms of nicotine-induced reproductive diseases. [ABSTRACT FROM AUTHOR]

OBJECTIVE: The aim of this study was to detect the expression of micro ribonucleic acid (miR)-335-5p in the liver tissues of patients with liver cancer, and to explore its effect on liver cancer and mechanism using Huh7 human liver cancer cells. PATIENTS AND METHODS: Liver tissues were collected from patients with liver cancer. The expression of miR-335-5p in tissues was detected via quantitative reverse transcription-polymerase chain reaction (qRT-PCR). Subsequently, Huh7 cells were transfected with miR-335-5p in vitro. After overexpressing miR-335-5p, changes in the expression of octamer-binding transcription factor 4 (Oct4) gene were observed via qRT-PCR. Furthermore, the proliferation of Huh7 cells and the protein expressions of protein kinase B (Akt) and phosphorylated Akt (p-Akt) were detected using cell counting kit (CCK)-8 assay and Western blotting (WB), respectively. RESULTS: Compared with Control group, the expression of miR-335-5p increased significantly in the liver tissues of liver cancer patients (p<0.01). In comparison with those in negative group, the messenger RNA (mRNA) expression of Oct4 and the proliferation rate of Huh7 cells were both significantly inhibited in miR-335-5p group (p<0.01, p<0.05). After overexpression of miR-335-5p, the protein expression level of p-Akt decreased remarkably (p<0.01). CONCLUSIONS: MiR-335-5p directly binds to the 3' untranslated region (3'UTR) of Oct4 mRNA to restrain the phosphorylation of Akt, thereby inhibiting Huh7 cell proliferation. [ABSTRACT FROM AUTHOR]

The present study is aimed to validate expression of transcriptional factors mediating postnatal development of adrenal zona fasciculata in rats exposed to low doses of endocrine disrupter dichlorodiphenyltrichloroethane prenatally and postnatally. Histological and immunohistochemical examination of the adrenals was performed. Impaired blood circulation, dystrophy and cell death were found in zona fasciculata of pubertal rats after developmental exposure to low doses of dichlorodiphenyltrichloroethane. Reparation of zona fasciculata was associated with increased number of Sonic hedgehog- and Oct4-expressing adrenal cortical cells but not in areas of regeneration. These data suggest that cell death may promote upregulation of factors inducing and maintaining pluripotent state in fasciculata cells for restoration of tissue homeostasis. Termination of growth of the adrenals after puberty was associated with upregulation of antiproliferative factor Hhex and decrease of cell proliferation. Dichlorodiphenyltrichloroethane exposure disrupted transcriptional control of cell proliferation by downregulation of Hhex expression in fasciculata cells. Decrease of proliferation in the exposed rats was mediated by inhibition of Sonic hedgehog and Oct4 expression and suppression of canonical Wnt signaling. The present study elucidated an alternative mechanism of proliferation control activated by endocrine disrupter dichlorodiphenyltrichloroethane through transition of fasciculata cells from pluripotent state and higher proliferative potential to differentiation. Activation of the alternative mechanism of growth control may probably affect maintenance of tissue homeostasis of zona fasciculata in postnatal development. [ABSTRACT FROM AUTHOR]

Oct4, a key transcription factor, could reprogram human somatic fibroblasts into embryonic stem cell-like pluripotent cells. The exact mechanism of cyclosporine A (CsA)-induced gingival overgrowth is still unclear. The aim of this study was to investigate the effects of CsA on the expression of Oct4 in cultured human gingival fibroblasts (HGFs) in vitro. The effects of CsA on HGFs were used to elucidate whether Oct4 expression could be induced by CsA by using quantitative real-time reverse transcription-polymerase chain reaction and western blot. Cell growth in CsA-treated HGFs with Oct4 lentiviral-mediated shRNAi knockdown was evaluated by tetrazolium bromide reduction assay. CsA was found to upregulate Oct4 transcript in a dose-dependent manner (p < 0.05). CsA also dose-dependently increased Oct4 protein expression (p < 0.05). The lentivirus expressing sh-Oct4 successfully prevented the CsA-induced Oct4 mRNA and protein in HGFs (p < 0.05). However, knockdown of Oct4 was insufficient to inhibit CsA-stimulated cell growth in HGFs. Furthermore, double knockdown with pluripotency-associated transcription factor Nanog showed that the down-regulation of Oct4/Nanog by lentiviral infection significantly inhibited CsA-stimulated cell growth (p < 0.05). Taken together, CsA was first found to upregulate Oct4 mRNA and protein expression in HGFs. The silencing Oct4 could not suppress cell growth unless Nanog was repressed simultaneously. [ABSTRACT FROM AUTHOR]

Abstract Developmental pluripotency associated factor 4 (Dppa4) is a highly specific marker of pluripotent cells, and is also overexpressed in certain cancers, but its function in either of these contexts is poorly understood. In this study, we use ChIP-Seq to identify Dppa4 binding genome-wide in three distinct cell types: mouse embryonic stem cells (mESC), embryonal carcinoma cells, and 3T3 fibroblasts ectopically expressing Dppa4. We find a core set of Dppa4 binding sites shared across cell types, and also a substantial number of sites unique to each cell type. Across cell types Dppa4 shows a preference for binding to regions with active chromatin signatures, and can influence chromatin modifications at target genes. In 3T3 fibroblasts with enforced Dppa4 expression, Dppa4 represses the cell cycle inhibitor Cdkn2c and activates Ets family transcription factor Etv4, leading to alterations in the cell cycle that likely contribute to the oncogenic phenotype. Dppa4 also directly regulates Etv4 in mESC but represses it in this context, and binds with Oct4 to a set of shared targets that are largely independent of Sox2 and Nanog, indicating that Dppa4 functions independently of the core pluripotency network in stem cells. Together these data provide novel insights into Dppa4 function in both pluripotent and oncogenic contexts. Highlights • Dppa4 binds to a shared subset of targets in pluripotent and cancer cells. • Dppa4 associates primarily with active chromatin domains. • Dppa4 represses Cdkn2c and activates Etv4 to promote cell proliferation. • In stem cells Dppa4 binds with Oct4 at shared targets independent of Sox2 and Nanog. [ABSTRACT FROM AUTHOR]

Skin is an extensive and easily accessible organ possessing various cell types that are constantly renewed. Previous studies have suggested the presence of a stem cell niche at the bulge region of the hair follicle, which contains cells positive for CD200 and CD34. Thus, this study sought to identify these cell populations in canine skin cells using the following methods 1- collecting samples of adult and fetal skin and isolating and culturing these cells using a method of simple enzymatic digestion and 2- testing the cell cultures for CD200 and CD34 in vitro and comparing them with skin tissue samples ( in situ ). Immunofluorescence results were negative for both CD200 and CD34 in frozen and paraffin embedded tissue, whereas the analysis showed that cultured cells positive for CD34, CD200 and double positive cells could be visualized in different percentages. Additionally, the pluripotency marker OCT4 was positive in the isolated cells. Analysis of CD34, CD200 and OCT4 by RT-qPCR showed that there is expression in fetal and adult cells, although no difference was observed between groups. Our results suggest that bulge stem cells from both fetuses and adult dogs were reported with the use of CD34 and CD200 markers in this study, and further techniques for cell isolation and in vitro cultivation are needed in order to obtain enriched populations of skin stem cells in dogs. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the association of cancer stem-cell markers [octamer-binding transcription factor 4 (OCT4), sex determining region Y-box 2 (SOX2), and Nanog homebox (NANOG)] expression with clinicopathological properties and overall survival (OS) in operative rectal cancer (RC) patients receiving adjuvant therapy. Materials and Methods: 153 patients with primary RC receiving surgery were enrolled. Tumor tissue and paired adjacent normal tissue sample were collected, and OCT4, SOX2, and NANOG expressions were assessed by immunofluorescent staining. The median follow-up duration was 5.2 years, and the last follow-up date was August 2016. Results: Tumor tissue OCT4 (p<0.001), SOX2 (p=0.003), and NANOG (p<0.001) expressions were higher than those in adjacent tissue. OCT4 expression was positively correlated with pathological grade (R=0.185, p=0.022), tumor size (R=0.224, p=0.005), and N stage (R=0.170, p=0.036). NANOG expression was positively associated with tumor size (R=0.169, p=0.036). Kaplan-Meier suggested that OCT4+ was associated with worse OS compared with OCT4- (p<0.001), while no association of SOX2 (p=0.121) and NANOG expressions (p=0.195) with OS was uncovered. Compared with one or no positive marker, at least two positive markers were associated with shorter OS (p<0.001), while all three positive markers were correlated with worse OS compared with two or less positive markers (p<0.001). Multivariate Cox's analysis revealed that OCT4+ (p<0.001) and N stage (p=0.046) were independent factors for shorter OS. Conclusion: Tumor tissue OCT4 expression was correlated with poor differentiation, tumor size, and N stage, and it can serve as an independent prognostic biomarker in operative patients with RC receiving adjuvant therapy. [ABSTRACT FROM AUTHOR]

The development of human induced pluripotent stem cells (iPSCs) holds great promise for regenerative medicine. However the iPSC induction efficiency is still very low and with lengthy reprogramming process. We utilized the highly potent transactivation domain (TAD) of MYC protein to engineer the human OCT4 fusion proteins. Applying the MYC-TAD-OCT4 fusion proteins in mouse iPSC generation leads to shorter reprogramming dynamics, with earlier activation of pluripotent markers in reprogrammed cells than wild type OCT4 (wt-OCT4). Dramatic enhancement of iPSC colony induction efficiency and shortened reprogramming dynamics were observed when these MYC-TAD-OCT4 fusion proteins were used to reprogram primary human cells. The OCT4 fusion proteins induced human iPSCs are pluripotent. We further show that the MYC Box I (MBI) is dispensable while both MBII and the linking region between MBI/II are essential for the enhanced reprogramming activity of MYC-TAD-OCT4 fusion protein. Consistent with an enhanced transcription activity, the engineered OCT4 significantly stimulated the expression of genes specifically targeted by OCT4-alone, OCT4/SOX2, and OCT4/SOX2/KLF4 during human iPSC induction, compared with the wt-OCT4. The MYC-TAD-OCT4 fusion proteins we generated will be valuable tools for studying the reprogramming mechanisms and for efficient iPSC generation for humans as well as for other species. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To investigate the expression of OCT4 and its clinical significance in laryngeal squamous carcinoma tissues. PATIENTS AND METHODS: Immunohistochemical staining was used to analyze the expression of OCT4 in 61 cases of laryngeal squamous carcinoma and 10 cases of the adjacent normal laryngeal tissues. RESULTS: The expression of OCT4 was not detected in normal laryngeal tissues, but could be detected in the nucleus of laryngeal carcinoma. The positive expression rates of OCT4 in well-moderately differentiated and poorly differentiated laryngeal squamous carcinoma tissues were 25.6% (11/43) and 66.7% (12/18) respectively, and there were significant differences (p < 0.01). The expression of the OCT4 protein was related to lymph node metastasis and TNM stage (p < 0.05), but not to gender, age and position of the tumor (p > 0.05). CONCLUSIONS: OCT4 is expressed in laryngeal squamous carcinoma tissues and is closely related to the cell differentiation of laryngeal carcinoma, lymph node metastasis and clinical stage. [ABSTRACT FROM AUTHOR]

Background: Cancer stem cells (CSCs) are a subset of cells within the bulk of a tumor that have the ability to self-renew and differentiate, and are thus associated with cancer invasion, metastasis, and recurrence. Phenethyl isothiocyanate (PEITC) is a natural compound found in cruciferous vegetables such as broccoli and is used as a cancer chemopreventive agent; however, its effects on CSCs are little known.Purpose: To evaluate the effect of PEITC on CSCs in this study by examining CSC properties.Methods: NCCIT human embryonic carcinoma cells were treated with PEITC, and the expression of pluripotency factors Oct4, Sox-2, and Nanog were evaluated by luciferase assay and western blot. Effect of PEITC on self-renewal capacity and clonogenicity were assessed with the sphere formation, soft agar assay, and clonogenic assay in an epithelial cell adhesion molecule (EpCAM)-expressing CSC model derived from HCT116 colon cancer cells using a cell sorting system. The effect of PEITC was also investigated in a mouse xenograft model obtained by injecting nude mice with EpCAM-expressing cells.Results: We found that PEITC treatment suppressed expression of the all three pluripotency factors in the NCCIT cells, in which pluripotency factors are highly expressed. Moreover, PEITC suppressed the self-renewal capacity and clonogenicity in the EpCAM-expressing CSC model. EpCAM was used as a specific CSC marker in this study. Importantly, PEITC markedly suppressed both tumor growth and expression of three pluripotency factors in a mouse xenograft model.Conclusion: These results demonstrate that PEITC might be able to slow down or prevent cancer recurrence by suppressing CSC stemness. [ABSTRACT FROM AUTHOR]

The Oct4 gene codes for a transcription factor that plays a critical role in the maintenance of pluripotency in embryonic and cancer stem cells. Its expression thus has to be tightly regulated. We performed biophysical characterization of the promoter region using a combination of UV absorption, CD, and NMR spectroscopies, native PAGE and chemical probing, which was followed by functional studies involving luciferase reporter assays performed in osteosarcoma and human embryonic stem cell lines. We have shown that the evolutionarily conserved G-rich region close to the Oct4 transcription start site in the non-template strand forms a parallel G-quadruplex structure. We characterized its structure and stability upon point mutations in its primary structure. Functional studies then revealed that whereas the wild type quadruplex sequence ensures high reporter gene expression, the expression of mutated variants is significantly decreased proportionally to the destabilizing effect of the mutations on the quadruplex. A ligand, N-methyl mesoporphyrin IX that increases the stability of formed quadruplex rescued the reporter expression of single-mutated variants to the level of wild-type, but it has no effect on a mutated variant that cannot form quadruplex. These data indicate that the quadruplex acts as a strong, positive regulator of Oct4 expression and as such it might serve as a potential target for therapeutic intervention. [ABSTRACT FROM AUTHOR]

OCT4 (POU5F1) is a major regulator of cell pluripotency and plays an important role not only during embryogenesis but also in tumorigenesis. It has been studied in various types of cancers, since stemness is an important factor for cancer growth and therapy. Here we present basic information about the OCT4 gene, its isoforms and pseudogenes besides discussing the current literature in which OCT4 is linked to cancer, emphasizing its roles in tumorigenesis and therapy. The majority of studies indicated a negative correlation between the expression of OCT4 and prognosis, and only in testicular germ cell tumor this correlation was positive. Using The Cancer Genome Atlas database we showed that OCT4 expression correlated negatively with patient survival in pancreatic cancer. All those different impacts of OCT4 on cancer indicate the biological complexity of this transcription factor in biology and, therefore, also in cancer. [ABSTRACT FROM AUTHOR]

Considerable progress has been made in understanding the roles of Sox2 and Oct4 in embryonic stem cells and mammalian embryogenesis. Specifically, significant progress has been made in answering three questions about the functions of Sox2 and Oct4, which are the focus of this review. 1) Are the first or second cell lineage decisions during embryogenesis controlled by Oct4 and/or Sox2? 2) Do the levels of Oct4 and Sox2 need to be maintained within narrow limits to promote normal development and to sustain the self-renewal of pluripotent stem cells? 3) Do Oct4 and Sox2 work closely together or is the primary role of Sox2 in pluripotent cells to ensure the expression of Oct4? Although significant progress has been made in answering these questions, additional studies are needed to resolve several important remaining issues. Nonetheless, the preponderance of the evidence suggests there is considerable crosstalk between Sox2 and Oct4, and further suggests Sox2 and Oct4 function as molecular rheostats and utilize negative feedback loops to carefully balance their expression and other critical genes during embryogenesis. This article is part of a Special Issue entitled: The Oct transcription factor family, edited by Dr. Dean Tantin. [ABSTRACT FROM AUTHOR]

Background/aim In cryptorchidism perinatal failure to switch off Oct4, a germ cell (GC) marker, may lead to carcinoma in situ . We aimed to analyze Oct4 expression during mouse gonocyte transformation into spermatogonial stem cells (SSC). Materials and methods Testes from OG2 (Oct4-promoter driven e GFP) mice at embryonic day (E) 17 and postnatal day P0–10 underwent immunohistochemistry and immunoblotting. Antibodies against MVH, AMH, Ki67, and c-Kit were visualized by confocal microscopy. Numbers of Oct4-GFP + GC and Oct4-GFP − GC/tubule were counted using ImageJ. Data were analyzed using nonparametric one-way ANOVA. Results GC from E17-P4 were Oct4-GFP + . Numbers of Oct4-GFP − GC/tubule increased from P6–10, whereas Oct4-GFP + GC/tubule numbers remained similar between P6 and P10. Sertoli cells proliferated from E17–P10, whereas GC only proliferated from P2. Gonocytes (Oct4-GFP + /c-Kit − ) central in tubules migrated to the basement membrane to become prospermatogonia (Oct4-GFP + /c-Kit − ) and then SSC (Oct4-GFP + /c-Kit + ) from day 4 and further developed into Oct4-GFP − /c-Kit + at P6. Conclusion In Oct4-GFP mice both centrally located gonocytes and prospermatogonia located at the tubular basement membrane were Oct4-GFP + /c-Kit − before further developing into SSC (Oct4-GFP + /c-Kit + ). This indicates that Oct4 is important in gonocyte transformation into SSC. Understanding this process will aid GC tumor diagnostics and fertility potential in boys with UDT undergoing orchidopexy. [ABSTRACT FROM AUTHOR]

The article focuses on a research on activation of human transcription factor genes by nuclear actin. Topics discussed include involvement of cellular functions like cell division and cell mobility in formation of cytoskeleton, transplantation of somatic cell nuclei into oocytes of Xenopus subjects to gene reprogramming and, role of heterodimer in histone modification and multiple chromatin remodeling complexes.

Copyright of Chinese Journal of Lung Cancer is the property of Chinese Journal of Lung Cancer and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Transcription factors that drive non-neoplastic myelomonocytic differentiation are well characterized but have not been systematically analyzed in the leukemic context. We investigated widely used, patient-derived myeloid leukemia cell lines with proclivity for differentiation into granulocytes by retinoic acid (RA) and/or monocytes by 1,25-dihyrdroxyvitamin D3 (D3). Using K562 (FAB M1), HL60 (FAB M2), RA-resistant HL60 sublines, NB4 (FAB M3), and U937 (FAB M5), we correlated nuclear transcription factor expression to immunophenotype, G1/G0 cell cycle arrest and functional inducible oxidative metabolism. We found that myelomonocytic transcription factors are aberrantly expressed in these cell lines. Monocytic-lineage factor EGR1 was not induced by D3 (the monocytic inducer) but instead by RA (the granulocytic inducer) in lineage bipotent myeloblastic HL60. In promyelocytic NB4 cells, EGR1 levels were increased by D3, while Gfi-1 expression (which promotes the granulocytic lineage) was upregulated during D3-induced monocytic differentiation in HL60, and by RA treatment in monocytic U937 cells. Furthermore, RARα and VDR expression were not strongly correlated to differentiation. In response to different differentiation inducers, U937 exhibited the most distinct transcription factor expression profile, while similarly mature NB4 and HL60 were better coupled. Overall, the differentiation induction agents RA and D3 elicited cell-specific responses across these common FAB M1-M5 cell lines. [ABSTRACT FROM AUTHOR]

Previous studies by the authors have described a novel cytoplasmic staining pattern with OCT4 in normal adrenal medullary tissue and in paragangliomas. We aimed to determine if this type of staining is found in other neuroendocrine tissues by examining a broad range of neuroendocrine tumors. Fifty neuroendocrine tumors of various grades and primary organ sites were selected. All cases were immunostained with OCT4 and Ki-67. OCT4 reactivity was then scored for intensity (0-3+) and extent (0-3+). Ki-67 proliferation index was scored as a percentage of total tumor cells. Immunoelectron microscopy was performed to determine precise location of antibody binding within cells. Immunoreactivity was seen in 26 (96%) of 27 cases of carcinoid tumors. The same type of strong staining was seen in 4 (67%) of 6 moderately differentiated neuroendocrine tumors. Only 2 (12%) of 17 poorly differentiated neuroendocrine tumors showed similar staining. A strong, inverse correlation was seen with OCT4 and Ki-67 index. Immunoelectron microscopy showed binding of OCT4 antibody to neurosecretory granules. Cytoplasmic staining of OCT4 is a sensitive marker of neuroendocrine differentiation that has yet to be described in any other tissue or tumor type. These findings show that this antibody has a high affinity for well- to moderately differentiated neuroendocrine tumors. Although comparative studies with other markers and a more extensive analysis of other tissue types are necessary, cytoplasmic staining of OCT4 may prove to be a useful immunostain in the diagnosis of neuroendocrine tumors. [ABSTRACT FROM AUTHOR]

The POU5F1 transcription factor is the gatekeeper of the pluripotent state in mammals. It is essential for epigenetic reprogramming events and also for germ cell viability. Pou5f1 gene expression is tightly controlled during embryogenesis, but its regulatory regions are not fully deciphered. The GOF18ΔPE-EGFP transgene, harboring the enhanced green fluorescence protein reporter gene inserted into a 17- kilobase long mouse Pou5f1 genomic sequence, has been widely used to visualize pluripotent embryonic cells and primordial germ cells in the mouse and other mammalian species. This construct includes the Pou5f1 promoter under the control of the distal enhancer and also includes the Pou5f1 gene body and flanking sequences. In search of the essential regulatory regions of Pou5f1, we generated four shorter forms of this construct. We found that the shortest form, containing the Pou5f1 promoter and distal enhancer but lacking the gene body and upstream flanking sequences, correctly expressed EGFP in transiently transformed undifferentiated ES cells, correctly switched it off upon ES cell differentiation, and correctly kept it silenced in differentiated Hep3B cells. Similarly to the original GOF18ΔPE-EGFP, this shortest form was expressed in the fetal mouse gonad. Our data suggest that the Pou5fl distal enhancer and proximal promoter may be sufficient to specify transgene expression in pluripotent cells. [ABSTRACT FROM AUTHOR]

Background and objective In recent years, cases of lung adenocarcinoma morbidity have consistently grown. OCT4 is the key gene that controls the automatic renewal of stem cells, and regulates the proliferation and differentiation of cancer stem cells. The aim of this study is to detect OCT4 expression in lung adenocarcinoma tissues, and to evaluate its relevance in the metastasis, chemotherapeutic effect, and prognosis in lung adenocarcinoma patients. Methods Immunofluorescence method was employed to detect OCT4 expression in lung adenocarcinoma tissues. The relationship between OCT4 expression and clinical pathological indicators is examined through chi-square test. Moreover, the survival rate is calculated through the Kaplan-Meier survivorship curve. Finally, the relevance between the indicators and patient survival is estimated using Cox analysis. Results Among the 126 tissue samples of lung adenocarcinoma, 91 showed OCT4 positive cells. OCT4 expression is closely related to metastasis and chemoresistance in lung adenocarcinoma patients, and negatively corresponds to the patients' disease-free survival and survival periods. Conclusion OCT4 expression is related to metastasis and chemoresistance in lung adenocarcinoma patients, and thus indicates poor prognosis. [ABSTRACT FROM AUTHOR]

The article presents a study which focuses on neuron-like cells differentiation from parthenogenetic embryonic stem cells obtained from mice. Among the highlights of the study include karyotype analysis, differentiation potential of fertilized and parthenogenetic embryonic stem cells from mice, and parthenogenetic embryonic stem cells from autologous tissue.

The role that the transcription factor OCT4 plays during oocyte growth is yet unknown. In this review, we summarise the data on its potential role in the acquisition of oocyte developmental competence in the mouse. These studies describe the presence in MII oocytes and 2-cell embryos of an OCT4 transcriptional network that might be part of the molecular signature of maternal origin on which the inner cell mass and the embryonic stem cell-associated pluripotency is assembled and shaped. The Oct4-gene regulatory network thus provides a connection between eggs, early preimplantation embryos and embryonic stem cells. [ABSTRACT FROM AUTHOR]

Abstract: Umbilical cord blood (UCB) was collected from Thoroughbred mares at foaling, and stem cells were isolated. UCB stem cells were cultured in growth media (GM), GM + Fibroblast Growth Factor 2, GM + Flt3/Thrombopoietin/c-Kit ligand, or conditioned media. Population doubling times (PDTs) were calculated. UCB stem cells cultured in standard GM exhibited faster PDTs (30.07 ± 1.59 hours) than those cultured in any treatment media. PDT was further accelerated by cultivation in GM on fibronectin (26.99 ± 1.57 hours)-, collagen I (26.21 ± 1.18 hours)-, or gelatin (27.32 ± 1.50 hours)-coated surfaces. Time in culture increased PDT regardless of media or substrata conditions. Because Oct4, nanog, KLF4, Sox2, and c-myc are implicated in embryonic stem cell pluripotency, total RNA was harvested from UCB stem cells as well as mouse ES cells and analyzed by reverse-transcription polymerase chain reaction. Both populations expressed all transcripts. The persistence of Oct4, nanog, and Sox2 expression in UCB stem cells was monitored over time in culture. Oct4 was detected throughout the duration of the experiment. Sox2 and nanog expression was lost with time in culture. Cells cultured on protein matrices maintained nanog expression longer than those on uncoated plasticware. These phenotypes remain unaffected by the type of culture matrix and FGF2. However, the plasticity markers are lost with serial passage. [Copyright &y& Elsevier]

Summary: The prognosis and therapy for malignant ovarian germ cell tumors including embryonal carcinoma differ from those of other categories of ovarian tumors, making accurate diagnosis imperative for patient care. Because of its rarity, the protein markers and genomic alterations typifying primary ovarian embryonal carcinoma have not been fully characterized. The present study aims to establish a set of sensitive and specific protein markers useful for the diagnosis and delineation of ovarian embryonal carcinoma. Chromosomal 12p anomalies were analyzed by dual-color fluorescence in situ hybridization. In a series of 6 ovarian mixed germ cell tumors with a component of embryonal carcinomas, OCT4, CD30, SOX2, and glypican 3 expressions were analyzed immunohistochemically on formalin-fixed paraffin-embedded tissue specimens. The results were compared to 4 cases of mixed germ cell tumor that were originally mistaken for embryonal carcinoma. OCT4 marked the nuclei of 6 cases, among which 5 cases also showed glypican 3 expression indicative of an admixed yolk sac tumor component. SOX2 was positive in only 3 cases of embryonal carcinoma. In 1 case of mixed germ cell tumor containing embryonal carcinoma, embryoid bodies from a component of polyembryoma were demonstrated to be both OCT4 and CD30 positive. Two cases originally classified as embryonal carcinoma were OCT4 and CD30 negative and showed glypican 3 positivity. They were reclassified as solid variant of yolk sac tumor. Two other cases originally classified as embryonal carcinoma were OCT4 positive and CD30 negative and were classified as immature teratoma with neuroectodermal differentiation based on the immunohistochemical findings as well as morphologic features and were diagnosed as immature teratoma. Chromosome 12p alterations were identified in 5 of 6 cases of embryonal carcinomas. In summary, a panel of immunostains is more useful than a single biomarker in the differential diagnosis of ovarian germ cell tumors. Chromosome 12p fluorescence in situ hybridization combined with OCT4, CD30, and glypican 3 immunostains is useful in confirming the diagnosis of ovarian embryonal carcinoma. [Copyright &y& Elsevier]

It remains controversial whether blastomeres of 2-cell stage mouse embryos show bias in their contribution to the blastocyst and whether there is any effect of superovulation. Two cell stage embryos from CF1 mice were derived by either natural breeding (N) or superovulation (S) and cultured in vitro. At blastocyst, inner cell mass and trophectoderm were distinguished by Cdx2 and Oct4 immunostaining. A fluorescent dye (CM-Dil) was also used to tag individual blastomeres at the 2-cell stage, and the descendant cells identified by their red fluorescence. S and N embryos developed to blastocyst at the same rate and contained a similar number of cells. However, with S embryos, the descendants of the blastomere labeled with CM-Dil contributed predominantly to either the embryonic or abembryonic pole about 70% of the time, whereas most N embryos displayed random patterning, with no restriction to one or other of the poles. In Sembryos, but not N-embryos, the leading blastomere at second cleavage contributed preferentially to the embryonic pole of the blastocyst and the lagging blastomere to the abembryonic pole and hence mural trophectoderm. In addition, a tetrahedral rather than a "flat" morphology at the 4-cell stage of S-embryos was strongly biased to displaying the embryonic/abembryonic pattern at blastocyst, in contrast, S-embryos lacking a zona pellucida resembled N embryos in their patterning. In CF1 mice, superovulation has little effect on development to blastocyst, but enforces a greater degree of lineage restriction than natural breeding, most likely through constraints imposed by the zona pellucida. [ABSTRACT FROM AUTHOR]

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Vitamin A (retinol [Rol]) and its metabolites are essential for embryonic development. The Rol metabolite all- trans retinoic acid (RA) is a biologically active form of Rol. The orphan nuclear receptor chicken ovalbumin upstream promoter-transcription-factors (COUP-TF) proteins have been implicated in the regulation of several important biological processes, such as embryonic development and neuronal cell differentiation. Because there is evidence that COUP-TFs function in the retinoid signaling network during development and differentiation, we generated murine embryonic stem (ES) cell lines which stably and constitutively overexpress COUP-TF1 (NR2F1) and we analyzed RA-induced differentiation. COUP-TF1 overexpression resulted in reduced RA-associated growth arrest. A 2.4±0.17-fold higher Nanog mRNA level was seen in COUP-TF1 overexpressing lines, as compared with wild-type (WT) ES cells, after a 72 hr RA treatment. We also showed that COUP-TF1 overexpression enhanced RA-induced extraembryonic endoderm gene expression. Specifically, COUP-TF1 overexpression increased mRNA levels of GATA6 by 3.3±0.3-fold, GATA4 by 3.6±0.1-fold, laminin B1 (LAMB1) by 3.4±0.1-fold, LAMC1 by 3.4±0.2-fold, Dab2 by 2.4+0.1-fold, and SOX17 by 2.5-fold at 72 hr after RA treatment plus LIF, as compared with the increases seen in WT ES cells. However, RA-induced neurogenesis was unaffected by COUP-TF1 overexpression, as shown by the equivalent levels of expression of NeuroD1, nestin, GAP43 and other neuronal markers. Our results revealed for the first time that COUP-TF1 is an important signaling molecule during vitamin A (Rol)-mediated very early stage of embryonic development. [ABSTRACT FROM AUTHOR]

Abstract: Oct4 is a transcription factor that plays a crucial role in maintaining pluripotency of embryonic stem cells. Down-regulation of Oct4 is associated with the differentiation of trophectoderm cell lineage, from which the normal placenta derives. We investigated the methylation and expression status of Oct4 in normal placenta and gestational trophoblastic disease (GTD) as attempts to investigate the role of Oct4 in the pathogenesis of GTD. By methylation-specific PCR, we observed both methylated and unmethylated Oct4 alleles in all 25 first trimester and 10 term placentas while 33% (18/54) of hydatidiform moles, and two choriocarcinoma cell line (JEG3 and JAR), only displayed methylated Oct4 allele. By quantitative TaqMan real-time PCR, Oct4 mRNA was significantly reduced in hydatidiform moles (P =0.04), JEG3 and JAR (P =0.024) when compared with normal placentas. Oct4 methylation was significantly correlated with Oct4 mRNA expression in placenta and GTD (P =0.012). Hypermethylation in minimal promoter and exon 1 region of Oct4 were confirmed in JEG3 and JAR by bisulfite genomic sequencing. The Oct4 mRNA expression in JEG3 and JAR increased after treatment with 5-aza-2′-deoxycytidine and/or trichostatin A. Our findings suggest that Oct4 is down-regulated by hypermethylation in normal placenta and GTD and such process is important in pathogenesis of GTD. [Copyright &y& Elsevier]

Abstract: OCT4 is a POU-domain transcription factor that is expressed in embryonic stem cells and germ cells. OCT4 has been detected in specific types of testicular germ cell tumour (GCT), including seminoma and embryonal carcinoma. The aim of this study was to evaluate the role of OCT4 expression in the diagnosis of primary central nervous system (CNS) pure and mixed GCT. Seventeen formalin-fixed, paraffin-embedded tissues of primary CNS GCT were immunohistochemically studied. The 12 pure GCT samples comprised germinoma (5), yolk sac tumour (3), mature teratoma (2), and immature teratoma (2). The five cases of mixed GCT contained various components as follows: yolk sac tumour (4), embryonal carcinoma (3), mature teratoma (1), germinoma (2), polyembryoma (1) and immature teratoma (1). Diffuse and strong nuclear staining indicating OCT4 expression was detected in all cases of pure germinoma (5), and in all cases of mixed GCT containing embryonal carcinoma (3) and/or germinoma (2). There was no corresponding staining in pure GCT of yolk sac tumour, mature teratoma, or immature teratoma except in a primitive neuroectodermal component, or in mixed GCT containing components of yolk sac tumour, mature teratoma or immature teratoma. In conclusion, we found that OCT4 immunostaining is a useful diagnostic tool to assist in the identification of primary CNS embryonal carcinoma and germinoma. In CNS mixed GCT, OCT4 expression can be detected provided that the components include embryonal carcinoma and/or germinoma. [Copyright &y& Elsevier]

Human embryonic stem (ES) cells are usually co-cultivated with supporting cells consisting of short-term cultures of fibroblasts (not an immortalized line) in a medium lacking serum. This method has promoted important progress in the field, but suffers from certain disadvantages. By serial cultivation for 27 consecutive transfers and about 63 cell generations, we have evolved an immortalized line from fibroblastic cells of 12–13-day mouse embryos. This line (MMM) supports the multiplication of H9 cells better than the 3T3 line. It supports the growth of H9 cells as well as do available short-term fibroblast cultures, but maintains more effectively the stem cell character of the H9 cells, judging by their better retention of Oct4. We have made MMM cells resistant to blasticidin and zeocin, the most efficient antibiotics for selection of stable transformants. In the presence of zeocin, the resistant MMM were able to support multiplication and selection of ES cells transfected with an exogenous gene encoding zeocin resistance. [ABSTRACT FROM AUTHOR]

OCT4 is a core transcription factor involved in pluripotency maintenance in the early mammalian embryo. The POU5F1 gene that encodes the OCT4 protein is highly conserved across species, suggesting conserved function. However, studies in several species including mice, cattle, and pigs, suggest that there are differences in where and when OCT4 is expressed. Specifically, in the horse, several studies have shown that exposure to the uterine environment may be necessary to induce OCT4 expression restriction to the inner cell mass (ICM) of the developing embryo, suggesting that there may be equine-specific extrinsic regulators of OCT4 expression that have not yet been investigated. However, an alternative hypothesis is that this restriction may not be evident in equine embryos because of our inability to culture them to the epiblast stage, preventing the observation of this restriction. In vitro studies have identified that OCT4 is expressed in the immature equine oocyte and in the early equine embryo, but OCT4 expression has not been studied after the formation of the ICM in the equine embryo. Despite the gaps in knowledge about equine-specific functions of OCT4, this factor has been used in studies assessing equine embryonic stem cells and to induce pluripotency in equine somatic cells. This review describes the role of OCT4 in the equine embryo and its applications in equine stem cell research. • Oct4 is a transcription factor that acts in the early developing mammalian embryo to maintain pluripotency. • OCT4 was identified to restrict to the inner cell mass of the equine embryo as is seen in murine embryos, but for equine embryos, it appears that the uterine environment may be necessary to cause this restriction. • OCT4 induced pluripotent stem cells have a variety of clinical applications for use in equine regenerative medicine. [ABSTRACT FROM AUTHOR]

Objective To investigate the expression of Oct4 in human thoracic aortic dissection (TAD) and the regulation mechanisms of Oct4 on phenotype transition of human aortic smooth muscle cells (HASMCs). Methods Aortic samples from TAD patients (n = 12) and organ donors (n = 6) were collected. qRT-PCR, western blot, and immunohistochemistry were performed to identify Oct4 expression in aortic media. Immunofluorescence was performed to analyze Oct4 expression in primary HASMCs. Oct4A and Oct4B isoforms were detected. Gain-of-function experiments were performed to determine the effects of Oct4 on HASMC phenotype transition. Chromatin immunoprecipitation, luciferase assay, and rescue experiments were performed to analyze mechanisms of Oct4 on HASMC phenotype transition. Results Oct4 expression levels, especially the Oct4A isoform, were significantly higher in TAD patients compared with normal controls. Notably, Oct4 presented a strong and strict nuclear localization in primary HASMCs of TAD patients but a mild and diffuse distribution in both cytoplasm and nucleus in the control group. Overexpression of Oct4 induced dedifferentiation of HASMCs characterized by decreased contractile proteins and elevated migration capability. Krüppel-like factor 5 (KLF5) was found to be a directly regulated target gene of Oct4 in HASMCs. Furthermore, downregulation of KLF5 significantly alleviated the effects of Oct4 on phenotype transition of HASMCs. Conclusions Oct4 expression was significantly upregulated in aortic tissues and primary HASMCs of TAD patients. The increased Oct4 induced phenotype transition of HASMCs from the contractile type to the synthetic type by directly upregulating KLF5. [ABSTRACT FROM AUTHOR]