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1.
Radiol Case Rep ; 19(11): 4963-4969, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39247466

RESUMO

We present a case of pulmonary metastasis originating from renal angiomyolipoma (AML), as evidenced by whole-exome sequencing (WES) analysis. Although AML predominantly arises in the kidneys, it can emerge in various body parts, making it important to distinguish between multicentric development and metastasis. However, previous studies have not distinguished between these conditions. Our case features an 82-year-old woman with a history of renal AML who presented with multiple, randomly distributed, bilateral pulmonary nodules of varying size and pure fat densities. The patient's condition followed a benign course over 10 years. Through WES, we discovered shared mutations in pulmonary lesions that were absent in the patient's blood, including a pathological mutation in TSC2, suggesting a metastatic origin from renal AML. Knowledge of the pulmonary manifestations of AML and their distinctive imaging findings can help radiologists and clinicians diagnose and manage patients with similar presentations.

2.
J Cardiovasc Pharmacol ; 83(5): 433-445, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38422186

RESUMO

ABSTRACT: We previously reported a novel compound called S-nitroso- N -pivaloyl- d -penicillamine (SNPiP), which was screened from a group of nitric oxide donor compounds with a basic chemical structure of S-nitroso- N -acetylpenicillamine, to activate the nonneuronal acetylcholine system. SNPiP-treated mice exhibited improved cardiac output and enhanced diastolic function, without an increase in heart rate. The nonneuronal acetylcholine-activating effects included increased resilience to ischemia, modulation of energy metabolism preference, and activation of angiogenesis. Here, we performed transcriptome analysis of SNPiP-treated mice ventricles to elucidate how SNPiP exerts beneficial effects on cardiac function. A time-course study (24 and 48 hours after SNPiP administration) revealed that SNPiP initially induced Wnt and cyclic guanosine monophosphate-protein kinase G signaling pathways, along with upregulation of genes involved in cardiac muscle tissue development and oxytocin signaling pathway. We also observed enrichment of glycolysis-related genes in response to SNPiP treatment, resulting in a metabolic shift from oxidative phosphorylation to glycolysis, which was suggested by reduced cardiac glucose contents while maintaining adenosine tri-phosphate levels. In addition, SNPiP significantly upregulated atrial natriuretic peptide and sarcolipin, which play crucial roles in calcium handling and cardiac performance. These findings suggest that SNPiP may have therapeutic potential based on the pleiotropic mechanisms elucidated in this study.


Assuntos
Diástole , Perfilação da Expressão Gênica , Camundongos Endogâmicos C57BL , Doadores de Óxido Nítrico , Transdução de Sinais , Função Ventricular Esquerda , Animais , Transdução de Sinais/efeitos dos fármacos , Masculino , Doadores de Óxido Nítrico/farmacologia , Função Ventricular Esquerda/efeitos dos fármacos , Diástole/efeitos dos fármacos , Transcriptoma/efeitos dos fármacos , Glicólise/efeitos dos fármacos , Proteínas Quinases Dependentes de GMP Cíclico/metabolismo , Proteínas Quinases Dependentes de GMP Cíclico/genética , Via de Sinalização Wnt/efeitos dos fármacos , Fatores de Tempo , Penicilamina/farmacologia , Penicilamina/análogos & derivados , Camundongos , Fosforilação Oxidativa/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos
5.
BMC Gastroenterol ; 23(1): 339, 2023 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-37784019

RESUMO

BACKGROUND: Fluoropyrimidine-based postoperative adjuvant chemotherapy is globally recommended for high-risk stage II and stage III colon cancer. However, adjuvant chemotherapy is often associated with severe adverse events and is not highly effective in preventing recurrence. Therefore, discovery of novel molecular biomarkers of postoperative adjuvant chemotherapy to identify patients at increased risk of recurrent colorectal cancer is warranted. Autophagy (including mitophagy) is activated under chemotherapy-induced stress and contributes to chemotherapy resistance. Expression of autophagy-related genes and their single-nucleotide polymorphisms are reported to be effective predictors of chemotherapy response in some cancers. Our goal was to evaluate the relationship between single-nucleotide variants of autophagy-related genes and recurrence rates in order to identify novel biomarkers that predict the effect of adjuvant chemotherapy in colorectal cancer. METHODS: We analyzed surgical or biopsy specimens from 84 patients who underwent radical surgery followed by fluoropyrimidine-based adjuvant chemotherapy at Saitama Medical University International Medical Center between January and December 2016. Using targeted enrichment sequencing, we identified single-nucleotide variants and insertions/deletions in 50 genes, including autophagy-related genes, and examined their association with colorectal cancer recurrence rates. RESULTS: We detected 560 single-nucleotide variants and insertions/deletions in the target region. The results of Fisher's exact test indicated that the recurrence rate of colorectal cancer after adjuvant chemotherapy was significantly lower in patients with the single-nucleotide variants (c.1018G > A [p < 0.005] or c.1562A > C [p < 0.01]) of the mitophagy-related gene PTEN-induced kinase 1. CONCLUSIONS: The two single-nucleotide variants of PINK1 gene may be biomarkers of non-recurrence in colorectal cancer patients who received postoperative adjuvant chemotherapy.


Assuntos
Neoplasias Colorretais , Recidiva Local de Neoplasia , Humanos , Estudos Retrospectivos , Recidiva Local de Neoplasia/genética , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Biomarcadores , Quimioterapia Adjuvante , Nucleotídeos/uso terapêutico , Estadiamento de Neoplasias , Fluoruracila/uso terapêutico , Biomarcadores Tumorais/genética , PTEN Fosfo-Hidrolase/genética
6.
Pathol Int ; 73(9): 413-433, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37378453

RESUMO

Vimentin is a stable mesenchymal immunohistochemical marker and is widely recognized as a major marker of mesenchymal tumors. The purpose of the present study was to investigate if the vimentin expression status might serve as a significant predictor of outcomes in patients with invasive breast carcinoma of no special type (IBC-NST) and to investigate, by comprehensive RNA sequencing analyses, the mechanisms involved in the heightened malignant potential of vimentin-positive IBC-NSTs. This study, conducted using the data of 855 patients with IBC-NST, clearly identified vimentin expression status as a very important independent biological parameter for accurately predicting the outcomes in patients with IBC-NST. RNA sequence analyses clearly demonstrated significant upregulation of coding RNAs known to be closely associated with cell proliferation or cellular senescence, and significant downregulation of coding RNAs known to be closely associated with transmembrane transport in vimentin-positive IBC-NSTs. We conclude that vimentin-positive IBC-NSTs show heightened malignant biological characteristics, possibly attributable to the upregulation of RNAs closely associated with proliferative activity and cellular senescence, and downregulation of RNAs closely associated with transmembrane transport in IBC-NSTs.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Vimentina , Neoplasias da Mama/patologia
7.
Clin Exp Dent Res ; 9(4): 711-720, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37272305

RESUMO

OBJECTIVES: In recent years, an increase in oral cancer among elderly nonsmokers has been noted. The aim of this study was to identify novel oncogenes in oral cancer in older nonsmokers. MATERIAL AND METHODS: Whole-exome sequencing (WES) data from 324 oral cancer patients were obtained from The Cancer Genome Atlas. Single nucleotide variants (SNVs) and insertions/deletions (INDELs) were extracted from the WES data of older patients. Fisher's exact test was performed to determine the specificity of variants in these genes. Finally, SNVs and INDELs were identified by target enrichment sequencing. RESULTS: Gene ontology analysis of 112 genes with significant SNVs or INDELs in nonsmokers revealed that nonsynonymous SNVs in HECTD4 were significantly more frequent in nonsmokers than in smokers by target enrichment sequencing (p = .02). CONCLUSIONS: Further investigation of the function of HECTD4 variants as oncogenes in older nonsmokers is warranted.


Assuntos
Exoma , Neoplasias Bucais , Humanos , Idoso , não Fumantes , Polimorfismo de Nucleotídeo Único , Oncogenes/genética , Neoplasias Bucais/genética
8.
Int Cancer Conf J ; 12(1): 24-30, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36605848

RESUMO

In advanced urothelial carcinoma (UC), approximately 20% of patients respond to pembrolizumab, an anti-programmed cell death-1 (PD-1) antibody. Herein, we reported a single case of UC showing coexistence of sarcomatoid subtype and glandular differentiation. Notably, only glandular differentiation was recurrent, probably progressive, and metastatic, which showed complete response to pembrolizumab. An 80-year-old woman presented with hematuria and dysuria, and an intra-vesical tumor was detected on ultrasound. Transurethral resections (TUR) were performed three times. In the first TUR, a sub-pedunculated tumor and a flat lesion were closely but independently located. Pathologically, the sub-pedunculated tumor was an invasive UC, sarcomatoid subtype. Meanwhile, the flat lesion was invasive UC with glandular differentiation. Despite the second and the additional TUR, the tumor was growing and a lymph node metastasis was detected. The third TUR specimen showed UC with glandular differentiation, and a positive PD-L1 expression as well as high density CD8-positive lymphocytic cells infiltration were observed. Pembrolizumab was administered for four courses after terminating the chemotherapy. The CT scan revealed shrinkage of both primary tumor and metastases. Cystectomy and lymph nodes dissection were performed, and no residual carcinoma was detected. The therapeutic effect was regarded as pathological complete response. Pembrolizumab could be effective for special subtype or divergent differentiation of UC, particularly in an event of an 'immune hot' tumor. Supplementary Information: The online version contains supplementary material available at 10.1007/s13691-022-00568-5.

10.
Virchows Arch ; 481(2): 161-190, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35695928

RESUMO

Tumor budding grade is a very useful histological prognostic indicator for colorectal cancer patients. Recently, it has been also reported as a significant prognostic indicator in invasive breast carcinoma patients. Our group and others have previously reported that the presence of a fibrotic focus in the tumor is a very useful histological finding for accurately predicting the prognosis in patients with invasive carcinoma of no special type (ICNST) of the breast. The purpose of the present study was to investigate whether a grading system incorporating tumor budding in a fibrotic focus is superior to the conventional grading system for tumor budding to accurately predict outcomes in patients with ICNST. According to our new grading system, we classified the tumors into grade I (164 cases), grade II (581 cases), and grade III (110 cases), and the results clearly demonstrated the significant superiority of the new grading system over that of conventional tumor budding alone for accurately predicting outcomes in patients with ICNST. Our findings strongly suggest that tumor cells and tumor-stromal cells interaction play very important roles in tumor progression rather than tumor cells alone.


Assuntos
Neoplasias da Mama , Carcinoma , Mama/patologia , Neoplasias da Mama/patologia , Carcinoma/patologia , Feminino , Fibrose , Humanos , Gradação de Tumores
11.
Dev Biol ; 478: 222-235, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34246625

RESUMO

Peroxisome proliferator-activated receptor (PPAR) γ1, a nuclear receptor, is abundant in the murine placenta during the late stage of pregnancy (E15-E16), although its functional roles remain unclear. PPARγ1 is encoded by two splicing isoforms, namely Pparγ1canonical and Pparγ1sv, and its embryonic loss leads to early (E10) embryonic lethality. Thus, we generated knockout (KO) mice that carried only one of the isoforms to obtain a milder phenotype. Pparγ1sv-KO mice were viable and fertile, whereas Pparγ1canonical-KO mice failed to recover around the weaning age. Pparγ1canonical-KO embryos developed normally up to 15.5 dpc, followed by growth delays after that. The junctional zone of Pparγ1canonical-KO placentas severely infiltrated the labyrinth, and maternal blood sinuses were dilated. In the wild-type, PPARγ1 was highly expressed in sinusoidal trophoblast giant cells (S-TGCs), peaking at 15.5 dpc. Pparγ1canonical-KO abolished PPARγ1 expression in S-TGCs. Notably, the S-TGCs had unusually enlarged nuclei and often occupied maternal vascular spaces, disturbing the organization of the fine labyrinth structure. Gene expression analyses of Pparγ1canonical-KO placentas indicated enhanced S-phase cell cycle signatures. EdU-positive S-TGCs in Pparγ1canonical-KO placentas were greater in number than those in wild-type placentas, suggesting that the cells continued to endoreplicate in the mutant placentas. These results indicate that PPARγ1, a known cell cycle arrest mediator, is involved in the transition of TGCs undergoing endocycling to the terminal differentiation stage in the placentas. Therefore, PPARγ1 deficiency, induced through genetic manipulation, leads to placental insufficiency.


Assuntos
Ciclo Celular , Desenvolvimento Embrionário , Endorreduplicação , PPAR gama/genética , PPAR gama/metabolismo , Placenta/metabolismo , Trofoblastos/citologia , Animais , Diferenciação Celular , Feminino , Retardo do Crescimento Fetal , Técnicas de Inativação de Genes , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Placenta/anormalidades , Placenta/citologia , Insuficiência Placentária/etiologia , Gravidez , Transcrição Gênica , Trofoblastos/metabolismo
12.
Acta Otolaryngol ; 141(6): 640-645, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33794725

RESUMO

BACKGROUND: Human papillomavirus (HPV)-negative oropharyngeal squamous cell carcinoma shows a higher rate of radiation resistance than HPV-positive oropharyngeal squamous cell carcinoma (OPSCC). Radioresistant HPV-negative OPSCC is associated with unfavourable outcomes, but validated prognostic biomarkers remain lacking. AIMS/OBJECTIVES: This study investigated biomarkers for radioresistant HPV-negative OPSCC. MATERIAL AND METHODS: The Cancer Genome Atlas included miRNA sequence and mRNA sequence data from 528 HNSCC tumours. Of these, we used gene expression data for HPV-negative head and neck squamous cell carcinoma for which data were available on the effects of radiation, and compared miRNA sequence and mRNA sequence data between radioresistant and radiosensitive groups. We subsequently estimated downstream miRNA from the results. Finally, we validated miRNAs related to the outcomes of radiotherapy in our clinical cases. RESULTS: Investigation of miRNA sequence revealed expression of miR-130b as the greatest difference between radiosensitive and radioresistant groups. We subsequently evaluated miR-130b expression in our clinical OPSCC cases. Values of miR-130b >5.372 (low expression), determined from receiver operating characteristic curve analyses, were associated with significantly longer progression-free survival and overall survival (p = .006, p = .04, respectively). CONCLUSIONS AND SIGNIFICANCE: Our results suggest that miR-130b has potential as a biomarker for the radiosensitivity of HPV-negative OPSCC.


Assuntos
MicroRNAs , Neoplasias Orofaríngeas/radioterapia , Tolerância a Radiação , Carcinoma de Células Escamosas de Cabeça e Pescoço/radioterapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Feminino , Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Orofaríngeas/genética , Neoplasias Orofaríngeas/mortalidade , Papillomaviridae , Transcrição Reversa , Análise de Sequência de RNA , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/mortalidade , Análise de Sobrevida
13.
Biochim Biophys Acta Mol Cell Biol Lipids ; 1865(12): 158808, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32860884

RESUMO

Ezetimibe inhibits Niemann-Pick C1-like 1 (NPC1L1) protein, which mediates intracellular cholesterol trafficking from the brush border membrane to the endoplasmic reticulum, where chylomicron assembly takes place in enterocytes or in the intestinal absorptive epithelial cells. Cholesterol is a minor lipid constituent of chylomicrons; however, whether or not a shortage of cholesterol attenuates chylomicron assembly is unknown. The aim of this study was to examine the effect of ezetimibe, a potent NPC1L1 inhibitor, on trans-epithelial lipid transport, and chylomicron assembly and secretion in enterocytes. Caco-2 cells, an absorptive epithelial model, grown onto culture inserts were given lipid micelles from the apical side, and chylomicron-like triacylglycerol-rich lipoprotein secreted basolaterally were analyzed after a 24-h incubation period in the presence of ezetimibe up to 50 µM. The secretion of lipoprotein and apolipoprotein B48 were reduced by adding ezetimibe (30% and 34%, respectively). Although ezetimibe allowed the cells to take up cholesterol normally, the esterification was abolished. Meanwhile, oleic acid esterification was unaffected. Moreover, ezetimibe activated sterol regulatory element-binding protein 2 by approximately 1.5-fold. These results suggest that ezetimibe limited cellular cholesterol mobilization required for lipoprotein assembly. In such conditions, large lipid droplet formation in Caco-2 cells and the enterocytes of mice were induced, implying that unprocessed triacylglycerol was sheltered in these compartments. Although ezetimibe did not reduce the post-prandial lipid surge appreciably in triolein-infused mice, the results of the present study indicated that pharmacological actions of ezetimibe may participate in a novel regulatory mechanism for the efficient chylomicron assembly and secretion.


Assuntos
Anticolesterolemiantes/farmacologia , Células Epiteliais/efeitos dos fármacos , Ezetimiba/farmacologia , Gotículas Lipídicas/efeitos dos fármacos , Metabolismo dos Lipídeos/efeitos dos fármacos , Animais , Transporte Biológico/efeitos dos fármacos , Células CACO-2 , Células Epiteliais/metabolismo , Humanos , Absorção Intestinal/efeitos dos fármacos , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Gotículas Lipídicas/metabolismo , Camundongos Endogâmicos C57BL
14.
J Biol Chem ; 295(17): 5626-5639, 2020 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-32165496

RESUMO

pncRNA-D is an irradiation-induced 602-nt long noncoding RNA transcribed from the promoter region of the cyclin D1 (CCND1) gene. CCND1 expression is predicted to be inhibited through an interplay between pncRNA-D and RNA-binding protein TLS/FUS. Because the pncRNA-D-TLS interaction is essential for pncRNA-D-stimulated CCND1 inhibition, here we studied the possible role of RNA modification in this interaction in HeLa cells. We found that osmotic stress induces pncRNA-D by recruiting RNA polymerase II to its promoter. pncRNA-D was highly m6A-methylated in control cells, but osmotic stress reduced the methylation and also arginine methylation of TLS in the nucleus. Knockdown of the m6A modification enzyme methyltransferase-like 3 (METTL3) prolonged the half-life of pncRNA-D, and among the known m6A recognition proteins, YTH domain-containing 1 (YTHDC1) was responsible for binding m6A of pncRNA-D Knockdown of METTL3 or YTHDC1 also enhanced the interaction of pncRNA-D with TLS, and results from RNA pulldown assays implicated YTHDC1 in the inhibitory effect on the TLS-pncRNA-D interaction. CRISPR/Cas9-mediated deletion of candidate m6A site decreased the m6A level in pncRNA-D and altered its interaction with the RNA-binding proteins. Of note, a reduction in the m6A modification arrested the cell cycle at the G0/G1 phase, and pncRNA-D knockdown partially reversed this arrest. Moreover, pncRNA-D induction in HeLa cells significantly suppressed cell growth. Collectively, these findings suggest that m6A modification of the long noncoding RNA pncRNA-D plays a role in the regulation of CCND1 gene expression and cell cycle progression.


Assuntos
Pontos de Checagem do Ciclo Celular , Ciclina D1/genética , Regulação para Baixo , Genes bcl-1 , RNA Longo não Codificante/genética , Epigênese Genética , Células HeLa , Humanos , Metilação , Regiões Promotoras Genéticas
15.
Anticancer Res ; 39(11): 6041-6047, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31704830

RESUMO

BACKGROUND/AIM: We have previously reported that alternate-day S-1 had comparable effects and milder adverse events than the respective consecutive-day regimen in head and neck cancer (HNC) patients. The aim of this study was to investigate the anticancer effects of both regimens and underlying mechanisms in vitro. MATERIALS AND METHODS: Two head and neck squamous cell carcinoma (HNSCC) cell lines were treated with 5-FU given on an alternate-day or consecutive-day schedule. The relative inhibition (RI) of tumor growth was calculated. Cell cycle distributions and cyclin expression following 5-FU treatment were analyzed. RESULTS: The RI of both regimens was almost identical. The percentage of cells in S phase was significantly increased in the alternate-day group compared to the consecutive-day group (p<0.001). CONCLUSION: The cytotoxic effect of alternate-day was equivalent to that of consecutive-day. S-phase arrest was more prominently observed with the alternate-day regimen, which may help maintain 5-FU sensitivity in head and neck cancer cells.


Assuntos
Antimetabólitos Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Fluoruracila/farmacologia , Neoplasias de Cabeça e Pescoço/patologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Esquema de Medicação , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Humanos , Técnicas In Vitro , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Células Tumorais Cultivadas
16.
Sci Rep ; 9(1): 10933, 2019 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-31358774

RESUMO

YAP (also known as YAP1 or YAP65) is a transcriptional coactivator that interacts with a number of transcription factors including RUNX and TEAD and plays a pivotal role in controlling cell growth. YAP is classified as a proto-oncogene. However, the mechanism by which activated YAP induces cancerous changes is not well known. Here we demonstrate that overexpression of YAP in NIH3T3 cells was sufficient for inducing tumorigenic transformation of cells. Mechanistically, YAP exerts its function in cooperation with the TEAD transcription factor. Our data also show that cMYC is a critical factor that acts downstream of the YAP/TEAD complex. Furthermore, we also found that aberrant activation of YAP is sufficient to drive tumorigenic transformation of non-immortalized mouse embryonic fibroblasts. Together our data indicate that YAP can be categorized as a new type of proto-oncogene distinct from typical oncogenes, such as H-RAS, whose expression in non-immortalized cells is tightly linked to senescence.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas de Ciclo Celular/metabolismo , Transformação Celular Neoplásica/metabolismo , Proteínas de Ligação a DNA/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Fatores de Transcrição/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Ciclo Celular/fisiologia , Proteínas de Ciclo Celular/genética , Proteínas de Ligação a DNA/genética , Fibroblastos/metabolismo , Genes ras , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , MicroRNAs/metabolismo , Células NIH 3T3 , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fatores de Transcrição de Domínio TEA , Fatores de Transcrição/genética , Proteínas de Sinalização YAP
17.
Dev Growth Differ ; 59(8): 639-647, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28967672

RESUMO

The Oct4 gene is a master regulator of the pluripotent properties of embryonic stem cells (ESCs). Recently, Oct4 loci were shown to frequently localize in close proximity to one another during the early stage of cellular differentiation, implicating this event as an important prerequisite step for ESCs to exert their full differentiation potential. Although the differentiation capacity of embryonal carcinoma cells (ECCs), such as F9 and P19 ECC lines, is severely restricted compared with ESCs, ECCs bear a highly similar expression profile to that of ESCs including expression of Oct4 and other pluripotency marker genes. Therefore, we examined whether allelic pairing of Oct4 loci also occurs during differentiation of F9 and P19 ECCs. Our data clearly demonstrate that this event is only observed within ESCs, but not ECCs, subjected to induction of differentiation, indicating transient allelic pairing of Oct4 loci as a specific feature of pluripotent ESCs. Moreover, our data revealed that this pairing did not occur broadly across chromosome 17, which carries the Oct4 gene, but occurred locally between Oct4 loci, suggesting that Oct4 loci somehow exert a driving force for their allelic pairing.


Assuntos
Diferenciação Celular , Cromossomos Humanos Par 17 , Loci Gênicos , Células-Tronco Embrionárias Humanas/metabolismo , Fator 3 de Transcrição de Octâmero , Alelos , Linhagem Celular , Cromossomos Humanos Par 17/genética , Cromossomos Humanos Par 17/metabolismo , Células-Tronco Embrionárias Humanas/citologia , Humanos , Fator 3 de Transcrição de Octâmero/biossíntese , Fator 3 de Transcrição de Octâmero/genética
18.
Stem Cells ; 34(2): 322-33, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26523946

RESUMO

Identification of a gene set capable of driving rapid and proper reprogramming to induced pluripotent stem cells (iPSCs) is an important issue. Here we show that the efficiency and kinetics of iPSC reprogramming are dramatically improved by the combined expression of Jarid2 and genes encoding its associated proteins. We demonstrate that forced expression of JARID2 promotes iPSC reprogramming by suppressing the expression of Arf, a known reprogramming barrier, and that the N-terminal half of JARID2 is sufficient for such promotion. Moreover, JARID2 accelerated silencing of the retroviral Klf4 transgene and demethylation of the Nanog promoter, underpinning the potentiating activity of JARID2 in iPSC reprogramming. We further show that JARID2 physically interacts with ESRRB, SALL4A, and PRDM14, and that these JARID2-associated proteins synergistically and robustly facilitate iPSC reprogramming in a JARID2-dependent manner. Our findings provide an insight into the important roles of JARID2 during reprogramming and suggest that the JARID2-associated protein network contributes to overcoming reprogramming barriers.


Assuntos
Técnicas de Reprogramação Celular/métodos , Proteínas de Ligação a DNA , Expressão Gênica , Células-Tronco Pluripotentes Induzidas/metabolismo , Complexo Repressor Polycomb 2 , Receptores de Estrogênio , Fatores de Transcrição , Animais , Proteínas de Ligação a DNA/biossíntese , Proteínas de Ligação a DNA/genética , Fator 4 Semelhante a Kruppel , Camundongos , Complexo Repressor Polycomb 2/biossíntese , Complexo Repressor Polycomb 2/genética , Proteínas de Ligação a RNA , Receptores de Estrogênio/biossíntese , Receptores de Estrogênio/genética , Fatores de Transcrição/biossíntese , Fatores de Transcrição/genética
19.
Stem Cells ; 33(4): 1089-101, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25522312

RESUMO

Nucleostemin (NS) is a nucleolar GTP-binding protein that is involved in a plethora of functions including ribosomal biogenesis and maintenance of telomere integrity. In addition to its expression in cancerous cells, the NS gene is expressed in stem cells including embryonic stem cells (ESCs). Previous knockdown and knockout studies have demonstrated that NS is important to preserve the self-renewality and high expression levels of pluripotency marker genes in ESCs. Here, we found that forced expression of Nanog or Esrrb, but not other pluripotency factors, resulted in the dispensability of NS expression in ESCs. However, the detrimental phenotypes of ESCs associated with ablation of NS expression were not mitigated by forced expression of Rad51 or a nucleolar localization-defective NS mutant that counteracts the damage associated with loss of NS expression in other NS-expressing cells such as neural stem/progenitor cells. Thus, our results indicate that NS participates in preservation of the viability and integrity of ESCs, which is distinct from that in other NS-expressing cells.


Assuntos
Proteínas de Transporte/biossíntese , Células-Tronco Embrionárias/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Homeodomínio/biossíntese , Proteínas Nucleares/biossíntese , Receptores de Estrogênio/biossíntese , Animais , Proteínas de Ligação ao GTP , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Camundongos , Camundongos Endogâmicos ICR , Proteína Homeobox Nanog , Proteínas de Ligação a RNA
20.
Stem Cells ; 33(3): 713-25, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25385436

RESUMO

c-Myc and phosphatidylinositol 3-OH kinase (PI3K) both participate in diverse cellular processes, including cell cycle control and tumorigenic transformation. They also contribute to preserving embryonic stem cell (ESC) characteristics. However, in spite of the vast knowledge, the molecular relationship between c-Myc and PI3K in ESCs is not known. Herein, we demonstrate that c-Myc and PI3K function cooperatively but independently to support ESC self-renewal when murine ESCs are cultured under conventional culture condition. Interestingly, culture of ESCs in 2i-condition including a GSK3ß and MEK inhibitor renders both PI3K and Myc signaling dispensable for the maintenance of pluripotent properties. These results suggest that the requirement for an oncogenic proliferation-dependent mechanism sustained by Myc and PI3K is context dependent and that the 2i-condition liberates ESCs from the dependence of this mechanism.


Assuntos
Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Animais , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/biossíntese , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Diferenciação Celular/fisiologia , Proliferação de Células/fisiologia , Sistema de Sinalização das MAP Quinases , Camundongos , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases Ativadas por Mitógeno/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fator 2 Relacionado a NF-E2/biossíntese , Fator 2 Relacionado a NF-E2/genética , Fosfatidilinositol 3-Quinases/genética , Inibidores de Fosfoinositídeo-3 Quinase , Células-Tronco Pluripotentes/citologia , Células-Tronco Pluripotentes/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética
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