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1.
Journal of Central South University(Medical Sciences) ; (12): 165-171, 2023.
Artigo em Inglês | WPRIM | ID: wpr-971382

RESUMO

OBJECTIVES@#Laryngeal squamous cell carcinoma (LSCC) is a common malignant tumor of head and neck. Screening of target genes for malignant tumor therapy is one of the focuses of cancer research, with proto-oncogene and tumor suppressor gene as the breakthrough. It has become an urgent need to find the target gene related to the treatment and prognosis of LSCC.This study aims to explore the role of Lin28B and C-myc in LSCC by detecting the expressions of these two proteins and analyze the correlation between the expression of Lin28B and C-myc and clinicopathological features and prognosis of LSCC.@*METHODS@#We detected the expression of Lin28B and C-myc proteins in 102 specimens of LSCC and 90 specimens of adjacent tissues by immunochemistry, and analyzed the correlation between Lin28B and C-myc protein expressions in LSCC as well as the correlation between the expressions of the two proteins and the clinicopathological features of LSCC. At the same time, the Kaplan-Meier method was used to analyze the relation between Lin28B and C-myc protein levels with the postoperative survival rate of LSCC patients.@*RESULTS@#The protein levels of Lin28B and C-myc in the LSCC tissnes were significantly higher than those in the adjacent tissues (both P<0.05),and there was a positive correlation between the expression of Lin28B and C-myc in LSCC (r=0.476, P<0.05). The expression of Lin28B protein was closely related to age, lymph node metastasis, clinical stage, tumor size, and pathological differentiation of LSCC patients (all P<0.05). while the expression of C-myc protein was closely related to lymph node metastasis, clinical stage, tumor size, and pathological differentiation of LSCC patients (all P<0.05). A relevant survival analysis showed that in patients with higher level of Lin28B (P=0.001) or C-myc protein (P<0.001), the postoperative survival rate was relatively low.@*CONCLUSIONS@#Lin28B and C-myc proteins are highly expressed in LSCC with a positive correlation. Furthermore, they are closely related to lymph node metastasis, clinical stage, tumor size, pathological differentiation and prognosis, suggesting that both Lin28B and C-myc might be involved in the occurrence and development of LSCC.


Assuntos
Humanos , Carcinoma de Células Escamosas de Cabeça e Pescoço , Proteínas Proto-Oncogênicas c-myc/metabolismo , Neoplasias Laríngeas/diagnóstico , Carcinoma de Células Escamosas/genética , Metástase Linfática , Prognóstico , Neoplasias de Cabeça e Pescoço , Biomarcadores Tumorais/metabolismo , Proteínas de Ligação a RNA/genética
2.
Chinese Journal of Clinical Pharmacology and Therapeutics ; (12): 205-211, 2022.
Artigo em Chinês | WPRIM | ID: wpr-1014899

RESUMO

Lin28 is a highly conserved RNA-binding protein, including Lin28a and Lin28b. Lin28 is involved in many physiological processes such as cell differentiation, growth and metabolism. In recent years, it has been found that Lin28 is closely related to the pathogenesis and development of numerous major diseases. The relationships between Lin28 and related diseases such as tumor, cardiovascular disease and diabetes are reviewed in this article.

3.
Ciênc. rural (Online) ; 52(10): e20210171, 2022. tab, graf, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1364719

RESUMO

LIN28 is a RNA-binding protein including two highly conserved homologous, LIN28A and LIN28B. Proto-oncogenes such as LIN28A and LIN28B are generally targeted by the let-7 miRNAs in different types of human cancers. Here, we determined the expression of LIN28A in canine mammary tumor samples and the LIN28/let-7 pathway in canine mammary cell lines. In those cell lines, we identified a functional LIN28/let-7 pathway which exhibited high expression of let-7 members and low expression of its targets, including LIN28A and LIN28B. However, the mammary carcinoma tissue samples showed a frequent expression of LIN28A being expressed mainly in the epithelial cells. No association was observed between LIN28A expression and histopathological classification and grade, TNM and survival time. Our results suggested a possible role of the LIN28A protein in the development of canine mammary carcinomas due to the high frequency observed in the tumor samples (28 of 32). The in vitro experiments suggested that the LIN28/let-7 pathway is active in the tumor cells evaluated. However, more studies are necessary to elucidate the exact role of LIN28/let-7 pathway in canine mammary carcinomas.


LIN28 é uma proteína de ligação ao RNA, com duas formas homólogas altamente conservadas, LIN28A e LIN28B. Os proto-oncogenes LIN28A e LIN28B são regulados pela família de miRNAs let-7 em diferentes tipos de cânceres em humanos. No presente trabalho, o objetivo foi determinar a expressão de LIN28A em amostras de tumor mamário de cadelas e a via LIN28/let-7 em linhagens celulares mamárias caninas. Nestas linhagens, através das técnicas de qPCR e RNAseq, foi identificado que a via LIN28/let-7 apresenta-se funcional, com alta expressão dos membros da família let-7 e baixa expressão de seus alvos, entre eles LIN28A e LIN28B. No entanto, as amostras de tecidos de carcinomas mamários caninos demonstraram expressão frequente de LIN28A, sendo observada principalmente em células epiteliais. Não foram observadas associações entre expressão de LIN28A com classificação e gradação histopatológicas, TNM e tempo de sobrevida. Nossos resultados sugerem uma possível relação da proteína LIN28A no desenvolvimento de carcinomas mamários caninos devido à alta frequência observada nas amostras tumorais (28 de 32). Os experimentos in vitro sugerem que a via LIN28/let-7 é ativa nas linhagens celulares caninas avaliadas. Entretanto, estudos funcionais ainda são necessários para elucidar a função exata da via LIN28/let-7 nos carcinomas mamários caninos.


Assuntos
Animais , Feminino , Cães , Neoplasias Mamárias Animais/genética , Proteínas de Ligação a RNA/análise , MicroRNAs/análise , Reação em Cadeia da Polimerase
4.
Protein & Cell ; (12): 490-512, 2022.
Artigo em Inglês | WPRIM | ID: wpr-939864

RESUMO

LIN28 is an RNA binding protein with important roles in early embryo development, stem cell differentiation/reprogramming, tumorigenesis and metabolism. Previous studies have focused mainly on its role in the cytosol where it interacts with Let-7 microRNA precursors or mRNAs, and few have addressed LIN28's role within the nucleus. Here, we show that LIN28 displays dynamic temporal and spatial expression during murine embryo development. Maternal LIN28 expression drops upon exit from the 2-cell stage, and zygotic LIN28 protein is induced at the forming nucleolus during 4-cell to blastocyst stage development, to become dominantly expressed in the cytosol after implantation. In cultured pluripotent stem cells (PSCs), loss of LIN28 led to nucleolar stress and activation of a 2-cell/4-cell-like transcriptional program characterized by the expression of endogenous retrovirus genes. Mechanistically, LIN28 binds to small nucleolar RNAs and rRNA to maintain nucleolar integrity, and its loss leads to nucleolar phase separation defects, ribosomal stress and activation of P53 which in turn binds to and activates 2C transcription factor Dux. LIN28 also resides in a complex containing the nucleolar factor Nucleolin (NCL) and the transcriptional repressor TRIM28, and LIN28 loss leads to reduced occupancy of the NCL/TRIM28 complex on the Dux and rDNA loci, and thus de-repressed Dux and reduced rRNA expression. Lin28 knockout cells with nucleolar stress are more likely to assume a slowly cycling, translationally inert and anabolically inactive state, which is a part of previously unappreciated 2C-like transcriptional program. These findings elucidate novel roles for nucleolar LIN28 in PSCs, and a new mechanism linking 2C program and nucleolar functions in PSCs and early embryo development.


Assuntos
Animais , Camundongos , Diferenciação Celular , Embrião de Mamíferos/metabolismo , Desenvolvimento Embrionário , Células-Tronco Pluripotentes/metabolismo , RNA Mensageiro/genética , RNA Ribossômico , Proteínas de Ligação a RNA/metabolismo , Fatores de Transcrição/metabolismo , Zigoto/metabolismo
5.
Chinese Journal of Cancer Biotherapy ; (6): 261-266, 2020.
Artigo em Chinês | WPRIM | ID: wpr-821002

RESUMO

@# Objective: To investigate the effect and mechanism of RNA binding protein Lin28 on the 5-fluorouracil (5-Fu) sensitivity of HepG2 cells. Methods: HepG2 cells were transfected with plasmid pcDNA3.1-Lin28 or si-Lin28 (small interfering RNA of Lin28). qPCR and Western blotting were used to detect the expression of Lin28 in HepG2 cells after transfection. Changes of cell proliferation in transfected cells after 5-Fu treatment was detected by CCK8 assay and the 50% inhibitory concentration (IC50) was calculated. Flow cytometry was used to detect apoptotic rate after 5-Fu treatment and the expression of apoptosis-related protein was assayed by Western blotting. The mRNA expressions of drug-resistant miRNAs (let-7a and let-7b), as well as cancer stem cell markers (Oct4, Nanog and Sox2) after transfection were detected by qPCR. Results: As compared to the HepG2/Vector cells, the mRNA and protein expressions of Lin28 were significantly up-regulated in HepG2/Lin28 cells (P<0.05 or P<0.01). Over-expression of Lin28 significantly suppressed the sensitivity of HepG2 cells to 5-Fu (IC50elevated obviously, P<0.05) and significantly increased cell proliferation while decreased apoptotic rate and expression of apoptotic-related protein caspase-3 (all P<0.01). As compared to si-control group, expression of Lin28 in HepG2/si-Lin28 cells was significantly down-regulated (P<0.01). Lin28 knockdown significantly reduced cell proliferation and IC50 of 5-Fu (all P<0.01) but increased apoptotic rate and expression of apoptosis-related protein (P<0.01). Compared with HepG2/Vector group, expressions of let-7a and let-7b, as well as cancer stem cell markers (Oct4, Nanog and Sox2) were significantly increased in HepG2/Lin28 cells (all P<0.01); while these molecules were significantly decreased in HepG2/si-Lin28 cells as comparing to si-control group (all P<0.01). Conclusion: Lin28 can modulate the chemosensitivity of HepG2 cells by regulating the expression of miRNAs and the formation of cancer stem cells. Targeting Lin28 might be a promising approach to improve the chemotherapy efficacy in HCC.

6.
Chinese Journal of Practical Gynecology and Obstetrics ; (12): 681-685, 2019.
Artigo em Chinês | WPRIM | ID: wpr-816234

RESUMO

OBJECTIVE: To investigate the expression and clinical significance of Lin28 B in placenta of severe preeclampsia(SPE).METHODS: Forty SPE patients were admitted to Shengjing Hospital of China Medical University from August 2017 to August 2018,including 20 patients with early-onset severe preeclampsia(ESPE)and 20 patients with late onset severe preeclampsia(LSPE).Another 40 healthy pregnant women who had termination of pregnancy in late pregnancy due to various reasons were selected as the control group,including 20 cases in early-onset control group(N1) and 20 cases in late-onset control group(N2). RT-qPCR analysis,Western Blot analysis and immunohistochemistry were used to detect the Lin28 B expression levels in placenta of each group.RESULTS: The expression of Lin28 B in placenta was significantly lower in ESPE group than in N1 group(P0.05).The expression of Lin28 B in placenta of ESPE group was lower than that in LSPE group(P<0.05).CONCLUSION: The expression of Lin28 B in placenta of SPE patients is decreased,and the ESPE group was significantly lower than that in LSPE group,suggesting that Lin28 B may be associated with the pathogenesis and development of SPE.

7.
Braz. j. med. biol. res ; 51(7): e7220, 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-889115

RESUMO

An abnormality in the Lin28/let-7a axis is relevant to the progression of hepatitis B virus (HBV)-positive hepatocellular carcinoma (HCC), which could be a novel therapeutic target for this malignant tumor. The present study aimed to investigate the antiproliferative and anti-invasive effects of urolithin A in a stable full-length HBV gene integrated cell line HepG2.2.15 using CCK-8 and transwell assays. The RNA and protein expressions of targets were assessed by quantitative PCR and western blot, respectively. Results revealed that urolithin A induced cytotoxicity in HepG2.2.15 cells, which was accompanied by the cleavage of caspase-3 protein and down-regulation of Bcl-2/Bax ratio. Moreover, urolithin A suppressed the protein expressions of Sp-1, Lin28a, and Zcchc11, and elevated the expression of microRNA let-7a. Importantly, urolithin A also regulated the Lin28a/let-7a axis in transient HBx-transfected HCC HepG2 cells. Furthermore, urolithin A decelerated the HepG2.2.15 cell invasion, which was involved in suppressing the let-7a downstream factors HMGA2 and K-ras. These findings indicated that urolithin A exerted the antiproliferative effect by regulating the Lin28a/let-7a axis and may be a potential supplement for HBV-infected HCC therapy.


Assuntos
Humanos , Proteínas de Ligação a RNA/efeitos dos fármacos , Carcinoma Hepatocelular/tratamento farmacológico , Cumarínicos/farmacologia , MicroRNAs/efeitos dos fármacos , Neoplasias Hepáticas/tratamento farmacológico , Valores de Referência , Sincalida/análise , Fatores de Tempo , Replicação Viral/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Western Blotting , Reprodutibilidade dos Testes , Análise de Variância , Proteínas de Ligação a RNA/análise , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/virologia , MicroRNAs/análise , Proliferação de Células/efeitos dos fármacos , Células Hep G2 , Reação em Cadeia da Polimerase em Tempo Real , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/virologia
8.
Chinese Pharmacological Bulletin ; (12): 175-179,180, 2017.
Artigo em Chinês | WPRIM | ID: wpr-606138

RESUMO

Aim To examine the role and uderlying mechanisms of Lin28 /let-7d axis in the proliferation of lung fibrobalsts and fibroblasts-into-myfibroblasts tran-sition,and provide novel strategy for the treatment of idiopathic pulmonary fibrosis (IPF).Methods We induced experimental lung fibrosis in mice by intratra-cheally injection of bleomycin (BLM).Ang Ⅱ and TGF-β1 were used to induce fibrogenesis in cultured MRC-5 cells;qRT-PCR and Western blot were applied to determine the changes of Lin28B,collagen 1 α1 and collagen 3α1 ;MTT assay,Edu satining and immun-ofluoresence were used to examine the cell viability, proliferation and fibroblasts-into-myofibroblasts transi-tion in MRC-5 cells.Results Lin28B was increased in the lung of mice with experimental lung fibrosis and in MRC-5 cells treated with AngⅡ or TGF-β1 .Moreo-ver,Lin28B enhanced collagen deposition via inhibi-ting expression of let-7d,which maybe contribute to the progression of IPF.In addition,further studies showed that Lin28B promoted proliferation and fibro-blasts-into-myofibroblasts in MRC-5 cells.Conclusion Lin28B /let-7d axis contributes to fibrogenesis via promotes fibroblasts-into-myofibroblasts transition, which may provide novel approaches for lung fibrosis treatment.

9.
Journal of Chinese Physician ; (12): 1-4, 2016.
Artigo em Chinês | WPRIM | ID: wpr-493689

RESUMO

Objective Through detected the expression degree of Lin28b in three different malig-nant degree pancreatic cancer cell lines and human pancreatic cell line to study the relationship of pancreatic cancer and the express of Lin28b.Methods The RT-PCR was used to detect the expression degree of mR-NA in Lin28b in cell lines of PANC-1,BxPC-3,AsPC-1,HPC-Y5 and Western-blot was used to detect the expression degree of protein in Lin28b in cell lines of PANC-1,BxPC-3,AsPC-1,HPC-Y5,then discovering the differential expression.Results The Lin28b was high expression in three pancreatic cancer cell lines, also higher than human pancreatic cell lines,and the expression of difference had statistical significance. Conclusions The results suggested that Lin28b may play a role in the pathogenesis of pancreatic cancer, and there is a certain relationship between the expression of Lin28b and malignant degree of tumor cells.

10.
Protein & Cell ; (12): 100-113, 2016.
Artigo em Inglês | WPRIM | ID: wpr-757185

RESUMO

The let-7 miRNA was one of the first miRNAs discovered in the nematode, Caenorhabditis elegans, and its biological functions show a high level of evolutionary conservation from the nematode to the human. Unlike in C. elegans, higher animals have multiple isoforms of let-7 miRNAs; these isoforms share a consensus sequence called the 'seed sequence' and these isoforms are categorized into let-7 miRNA family. The expression of let-7 family is required for developmental timing and tumor suppressor function, but must be suppressed for the self-renewal of stem cells. Therefore, let-7 miRNA biogenesis must be carefully controlled. To generate a let-7 miRNA, a primary transcript is produced by RNA polymerase II and then subsequently processed by Drosha/DGCR8, TUTase, and Dicer. Because dysregulation of let-7 processing is deleterious, biogenesis of let-7 is tightly regulated by cellular factors, such as the RNA binding proteins, LIN28A/B and DIS3L2. In this review, we discuss the biological functions and biogenesis of let-7 miRNAs, focusing on the molecular mechanisms of regulation of let-7 biogenesis in vertebrates, such as the mouse and the human.


Assuntos
Animais , Humanos , Sequência de Bases , Regulação da Expressão Gênica , MicroRNAs , Química , Genética , Metabolismo , Processamento Pós-Transcricional do RNA , Estabilidade de RNA , Transcrição Gênica
11.
International Journal of Stem Cells ; : 169-175, 2016.
Artigo em Inglês | WPRIM | ID: wpr-88598

RESUMO

Müller glia (MG) are the primary support cells in the vertebrate retina, regulating homeostasis in one of the most metabolically active tissues. In lower vertebrates such as fish, they respond to injury by proliferating and reprogramming to regenerate retinal neurons. In mammals, MG may also react to injury by proliferating, but they fail to initiate regeneration. The barriers to regeneration could be intrinsic to mammalian MG or the function of the niche that cannot support the MG reprogramming required for lineage conversion or both. Understanding these mechanisms in light of those being discovered in fish may lead to the formulation of strategies to unlock the neurogenic potential of MG and restore regeneration in the mammalian retina.


Assuntos
Homeostase , Mamíferos , Neurogênese , Neuroglia , Regeneração , Retina , Neurônios Retinianos , Vertebrados
12.
Gut and Liver ; : 714-718, 2016.
Artigo em Inglês | WPRIM | ID: wpr-179858

RESUMO

BACKGROUND/AIMS: Although LIN28A is known to potentially play a role in the oncogenesis of various cancers, whether LIN28A expression is a predictor of poor prognosis in patients with gastric cancer has not been fully explored. We sought to evaluate clinicopathological characteristics according to the expression of LIN28A in numerous gastric cancer tissue samples. METHODS: LIN28A expression was evaluated by immunohistochemical (IHC) analysis of a tissue microarray comprising 288 gastric cancer tissues and 288 adjacent normal tissues. Clinicopathological characteristics, including overall survival, were compared according to LIN28A expression. RESULTS: The IHC staining score was lower for the cancer tissues than the normal tissues (p<0.001). However, no significant differences were observed in the clinicopathological characteristics between the low and high LIN28A expression groups. In addition, the 5-year overall survival rate did not differ between the two groups: 75.3% (95% confidence interval [CI], 69.3% to 81.7%) versus 71.6% (95% CI, 63.3% to 80.9%) for low versus high expression, respectively. CONCLUSIONS: The expression of LIN28A did not appear to play a distinct role in predicting the clinicopathological characteristics of patients with gastric cancer. In addition, LIN28A expression was not an independently associated factor for overall survival in patients with gastric cancer.


Assuntos
Humanos , Carcinogênese , Prognóstico , Neoplasias Gástricas , Taxa de Sobrevida
13.
Journal of Xi'an Jiaotong University(Medical Sciences) ; (6): 775-781, 2015.
Artigo em Chinês | WPRIM | ID: wpr-481156

RESUMO

Objective To explore whether CCL18 is involved in regulating the expression of miRNAs in breast cancer.Methods The expression profile of miRNAs in the breast cancer cell following CCL18 treatment was determined by miRNAs microarray analysis.Then we performed QRT-PCR and Luciferase Reporter Assay to validate the results from the miRNAs microassay.We used transient transfection to change the expression of miR98 and c-myc in breast cancer cells.We then used QRT-PCR and Western blot to analyze the mechanism by which CCL18 downregulates the expression of miR98 in breast cancer cells.Results miRNAs microarray analysis showed that cells treated with CCL18 differentially expressed 20 miRNAs genes compared with those in the control group. Our QRT-PCR and Luciferase Reporter Assay confirmed the result.The mRNA and protein expressions of C-myc and lin28 were increased after CCL18 stimulation in breast cancer cells.Transfection with c-myc siRNAs rescued the increase of lin28 and loss of miR98 expression caused by CCL18 stimulation.Our results also showed that CCL18 could upregulate the expression of N-Ras at post-transcription level.Conclusion CCL18 downregulates the expression of miR98 via N-Ras/c-myc/lin28 pathway.The downregulated miR98 increases the expression of N-Ras after transfection,which further activates c-myc/lin28 pathway and forms a positive feedback loop.

14.
Chinese Journal of Clinical Oncology ; (24): 530-533, 2014.
Artigo em Chinês | WPRIM | ID: wpr-446506

RESUMO

Lin28 is a highly conserved RNA-binding protein that has an important role in human body development, metabolism, and tumorigenesis. Previous studies have found that the activation of Lin28 can suppress the maturity of let-7 miRNA in stem cells and promote the proliferation of stem cells by upregulating cell-cycle related genes, such as cyclins A and B. Other mechanisms underlying the activation of Lin28 can selectively block the processes of pre-let-7 miRNA in embryonic stem cells and ultimately promote tumori-genesis. In addition, Lin28 affects the occurrence, development, and prognosis of cancer by inhibiting the differentiation and maturation of miRNA and by moderating the expression of some cell-cycle related genes. Lin28 has an important function in the tumor's tolerance of chemotherapy and radiotherapy. We review the physiological function of Lin28 in tumors and its function in tumor treatment.

15.
Chinese Journal of Applied Clinical Pediatrics ; (24): 574-577, 2014.
Artigo em Chinês | WPRIM | ID: wpr-446079

RESUMO

Timing of puberty showed a dramatic decrease in the past decades,and it depends on the gene,nutrition,environment,social economics,and so on.Childhood obesity affects both the timing of puberty and sex hormone levels.However,the influence of obesity on the timing of puberty has gender differences.Current studies show that childhood obesity accelerates the onset of puberty in girls,but it still has controversy in boys.Mechanisms of concrete have not clear,may be related to the subjectivity of standard of male sexual development and the correlation of body mass index as a substitute for male obesity is poor.Through literature review at home and abroad,this article will explain the influence of obesity on the timing of puberty,sex hormone levels and its gender differences,further explore the possible mechanisms of body fat participate in starting the gonad axis,and provide new research direction on the switch for the gonad axis.

16.
International Journal of Pediatrics ; (6): 48-50, 2014.
Artigo em Chinês | WPRIM | ID: wpr-444596

RESUMO

Puberty onset is triggered by re-emergence of the hypothalamic-pituitary-gonadal axis (HPGA),which is characterized by the significantly increasing amplitude and frequency of gonadotropin-releasing hormone (GnRH) secretion in human being.A series of studies found that many genes control puberty onset,including KISS1 and GPR54 gene,estrogen receptor (ESR) gene,energy balance-related genes,LIN28B gene,MKRN3 gene and so on.Studies have been confirmed that the mutation and single nucleotide polymorphisms (SNP) of the genes above are associated with early puberty.In this paper,the relationship between genetic alterations of these genes and early puberty are summarized as follows.-

17.
Acta Anatomica Sinica ; (6): 350-353, 2014.
Artigo em Chinês | WPRIM | ID: wpr-452045

RESUMO

Objective To observe the expression of tumor stem cell markers P 75NTR,Oct-4,Sox-2,Lin28 and Nanog in the tumor sphere from esophageal squamous cells carcinoma Eca 109 and identify the esophageal squamous cell cancer stem cell marker .Methods The serum-free culture method was used for generating tumor spheres: proliferation was observed in enrichment culture tumor spheres .Small tumor spheres were obtained after 5 days culture and big and round tumor spheres appeared after 14 days culture which were collected for experiments and passaged .The expression and location of P75NTR,Oct-4,Sox-2,Lin28, and Nanog were detected by immunofluorescence cytochemistry .Results The expressions of P75NTR,Oct-4 and Lin28 were positive in the center of tumor spheres and some on cytoplasm and other in nuclei of Eca109 monolayer cells.However, Oct-4 fluorescence intensity was weaker than P75NTR.The expressions of Sox-2 and Nanog were positive in cytoplasm of tumor spheres and Eca 109 monolayer cells .Conclusion The cells expressing P75NTR, Oct-4, and Lin28 in the center of the tumor sphere may be esophageal cancer stem cells .

18.
Experimental & Molecular Medicine ; : e55-2013.
Artigo em Inglês | WPRIM | ID: wpr-209543

RESUMO

Hematopoietic stem cells (HSCs) comprise a rare population of cells that can regenerate and maintain lifelong blood cell production. This functionality is achieved through their ability to undergo many divisions without activating a poised, but latent, capacity for differentiation into multiple blood cell types. Throughout life, HSCs undergo sequential changes in several key properties. These affect mechanisms that regulate the self-renewal, turnover and differentiation of HSCs as well as the properties of the committed progenitors and terminally differentiated cells derived from them. Recent findings point to the Lin28b-let-7 pathway as a master regulator of many of these changes with important implications for the clinical use of HSCs for marrow rescue and gene therapy, as well as furthering our understanding of the different pathogenesis of childhood and adult-onset leukemia.


Assuntos
Animais , Humanos , Diferenciação Celular , Linhagem da Célula , Células-Tronco Embrionárias/citologia , Proteína HMGA2/genética , Células-Tronco Hematopoéticas/citologia , Leucemia/etiologia , MicroRNAs/genética , Proteínas de Ligação a RNA/genética
19.
Clinical and Experimental Reproductive Medicine ; : 87-93, 2012.
Artigo em Inglês | WPRIM | ID: wpr-30939

RESUMO

OBJECTIVE: Lin28 has been known to control the proliferation and pluripotency of embryonic stem cells. The purpose of this study was to determine the downstream effectors of Lin28 in mouse embryonic stem cells (mESCs) by RNA interference and microarray analysis. METHODS: The control siRNA and Lin28 siRNA (Dharmacon) were transfected into mESCs. Total RNA was prepared from each type of transfected mESC and subjected to reverse transcription-polymerase chain reaction (RT-PCR) analysis to confirm the downregulation of Lin28. The RNAs were labeled and hybridized with an Affymetrix Gene-Chip Mouse Genome 430 2.0 array. The data analysis was accomplished by GenPlex 3.0 software. The expression levels of selected genes were confirmed by quantitative real-time RT-PCR. RESULTS: According to the statistical analysis of the cDNA microarray, a total of 500 genes were altered in Lin28-downregulated mESCs (up-regulated, 384; down-regulated, 116). After differentially expressed gene filtering, 31 genes were selected as candidate genes regulated by Lin28 downregulation. Among them, neuropeptide Y5 receptor and oocyte-specific homeobox 5 genes were significantly upregulated in Lin28-downregulated mESCs. We also showed that the families of neuropeptide Y receptor (Npyr) and oocyte-specific homeobox (Obox) genes were upregulated by downregulation of Lin28. CONCLUSION: Based on the results of this study, we suggest that Lin28 controls the characteristics of mESCs through the regulation of effectors such as the Npyr and Obox families.


Assuntos
Animais , Humanos , Camundongos , Quimera , Regulação para Baixo , Células-Tronco Embrionárias , Genes Homeobox , Genoma , Neuropeptídeo Y , Neuropeptídeos , Análise de Sequência com Séries de Oligonucleotídeos , Receptores de Neuropeptídeo Y , RNA , Interferência de RNA , RNA Interferente Pequeno , Estatística como Assunto
20.
Korean Journal of Pediatrics ; : 388-392, 2012.
Artigo em Inglês | WPRIM | ID: wpr-213506

RESUMO

PURPOSE: Single-nucleotide polymorphism (SNP) markers within LIN28B have been reported to be related to the timing of pubertal growth. However, no study has investigated the frequency of genetic markers in girls with precocious puberty (PP) or early puberty (EP). This study aimed to determine the frequency of putative genetic markers in girls with PP or EP. METHODS: Genomic DNAs were obtained from 77 and 109 girls that fulfilled the criteria for PP and EP, respectively. The controls in this study were 144 healthy volunteers between 20 and 30 years of age. The haplotypes were reconstructed using 11 SNPs of LIN28B, and haplotype association analysis was performed. The haplotype frequencies were compared. Differences in the clinical and laboratory parameters were analyzed according to the haplotype dosage. RESULTS: Eleven SNPs in LIN28B were all located in a block that was in linkage disequilibrium. The haplotype could be reconstructed using 2 representative SNPs, rs4946651 and rs369065. The AC haplotype was less frequently observed in the PP group than in the controls (0.069 vs. 0.144, P=0.010). The trend that girls with non-AC haplotypes tended to have earlier puberty onset (P=0.037) was illustrated even in the EP+PP patient group by Kaplan-Meier analysis. CONCLUSION: The results of the present study showed that non-AC haplotypes of LIN28B had a significant association with PP in girls.


Assuntos
Humanos , DNA , Marcadores Genéticos , Haplótipos , Desequilíbrio de Ligação , Polimorfismo de Nucleotídeo Único , Puberdade , Puberdade Precoce
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