Correlation between expression of Lin28B and C-myc in patients with laryngeal squamous cell carcinoma and clinicopathological features and prognosis / 中南大学学报(医学版)

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.

Protective mechanism of RNA binding protein LIN28 on diabetic nephropathy / 局解手术学杂志

Objective To explore the protective mechanism of RNA binding protein LIN28 on diabetic nephropathy(DN).Methods LIN28 was overexpressed or knocked down by adenovirus in HEK 293T cells.The gene and functional signaling pathway significantly changed after overexpression of LIN28 were obtained through RNA Seq transcriptome sequencing and bioinformatics analysis.HEK 293T cells were divided into the Control group,the Treatment group,the Adv-LIN28-OE+D-ribose group and the Adv-LIN28-NC+D-ribose group in in vitro LIN28 overexpression studies.And HEK 293T cells were divided into the Control group,the Treatment group,the Adv-shRNA LIN28+D-ribose group and the Adv-shRNA NT+D-ribose group in in vitro LIN28 knockdown studies.ELISA was used to detect the levels of human advanced glycation end products(AGEs)of cells supernatants in the above groups.Western blot was used to detect the expression levels of RAGE,NF-κB and MMP-2 of cells in the above groups.Results The results of RNA-Seq transcriptome sequencing,GO analysis and KEGG analysis showed that overexpression of LIN28 resulted in a significant down-regulation of AGE-RAGE signaling pathway in HEK 293T cells(P<0.05).The results of ELISA showed that compared with the Control group,the cell in the Treatment group produced a large amount of AGEs(P<0.05);compared with the Treatment group,the AGEs level of cells in the Adv-LIN28-OE+D-ribose group was significantly decreased(P<0.05),while the AGEs level of cells in the Adv-shRNA LIN28+D-ribose group was increased(P>0.05).The results of Western blot showed that compared with the Control group,the expression levels of RAGE,NF-κB and MMP-2 of cells in the Treatment group were significantly increased(P<0.05);compared with the Treatment group,the expression levels of RAGE,NF-κB and MMP-2 of cells in the Adv-LIN28-OE+D-ribose group were significantly decreased(P<0.05),while the expression levels of RAGE,NF-κB and MMP-2 of cells in the Adv-shRNA LIN28+D-ribose group were significantly increased(P>0.05).Conclusion Overexpression of LIN28 by adenovirus at the cellular level in vitro can lead to significant differential expression of thousands of genes.In particular,it can inhibit the diabetes and complications-related AGE-RAGE signaling pathway,which is critical in the progression of DN disease,and play a role in protecting DN.

Expression of serum miR-384 and LIN28B in diabetic retinopathy and their diagnostic value / 局解手术学杂志

Objective To investigate the expression levels of microRNA-384(miR-384)and LIN28B in serum of patients with diabetic retinopathy(DR)and their diagnostic value.Methods A total of 100 patients with type 2 diabetes diagnosed in our hospital from January 2020 to November 2021 were selected as the research subjects.According to the occurrence of retinopathy,the patients were divided into the non-DR group(40 cases)and the DR group(60 cases).In addition,40 healthy person who underwent physical examination in our hospital during the same period were regarded as the control group.The relative expression levels of serum miR-384 and LIN28B were detected by qRT-PCR,and the relationship between the two indexes and the general clinical data of DR patients was analyzed.Pearson method was applied to analyze the correlation between the expression of miR-384 and LIN28B in serum of DR patients.Logistic regression was applied to analyze the influencing factors of DR.The diagnostic value of serum miR-384 and LIN28B levels for DR patients was analyzed by receiver operating characteristic(ROC)curve.Results The level of serum miR-384 in the DR group was obviously lower than that in the non-DR group and the control group(P<0.05),and the non-DR group was lower than the control group(P<0.05).The level of serum LIN28B in the DR group was obviously higher than that in the non-DR group and the control group(P<0.05),and the non-DR group was higher than the control group(P<0.05).The expression levels of miR-384 and LIN28B were related to the course of diabetes and blood glucose(P<0.05).Pearson's correlation analysis showed that the expression of miR-384 was negatively correlated with LIN28B in serum of DR patients(r=-0.296,P<0.05).Logistic regression analysis showed that miR-384 and LIN28B were the independent influencing factors for DR(P<0.05).The results of ROC curve analysis showed that the area under the curve(AUC)of miR-384,LIN28B and the combination of two in DR patients was 0.625,0.646,and 0.682,respectively,and the specificity was 67.50%,85.00%,and 97.50%,respectively.Conclusion The serum expression of miR-384 is low and LIN28B is high in DR patients.Both miR-384 and LIN28B are the influencing factors for the occurrence of DR and are expected to be potential serological markers for the diagnosis of DR.

Lin28 overexpression promotes proliferation and inhibits osteogenic differentiation of human dental pulp stem cells in part through the mTOR signaling pathway / 安徽医科大学学报

Objective @#To investigate the effects of Lin28 overexpression on the proliferation and osteogenic differentiation of human dental pulp stem cells (hDPSCs) through mTOR signaling pathway.@*Methods @#After transfecting lentiviral vectors of Lin28 gene in hDPSCs , the relative expression of Lin28 was detected by Real⁃time PCR. CCK⁃8 assay was applied to detect the effect on cell proliferation. qRT⁃PCR was used to research the expression levels of alkaline phosphatase (ALP) , osteopontin (OPN) and osteocalcin (OCN) . Western blot assay was processed to investigate the effects on the relative expression levels of ALP and OPN proteins. Alizarin red staining was utilized to detect the mineralized nodules. @*Results @#Compared with the control group , the cell proliferation of transfection group was promoted (P < 0. 05) ; The mRNA and protein expression levels of ALP , OPN and OCN in transfection group were significantly lower than those in control group (P < 0. 05) , the expression level of ALP apparently decreased after the addition of mTOR inhibitor rapamycin (P < 0. 05) ; Alizarin red staining showed that the size and number of mineralized nodules formed in transfection group were markedly declined compared with empty carrier group (P < 0. 05) .@*Conclusion @#Overexpression of Lin28 can inhibit the osteogenic differentiation of hDP⁃ SCs through suppress mTOR signaling pathway.

LIN28 coordinately promotes nucleolar/ribosomal functions and represses the 2C-like transcriptional program in pluripotent stem cells

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.

Association of Lin28 with tumor, cardiovascular disease and diabetes / 中国临床药理学与治疗学

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.

Expression of LIN28A/B and Let-7 miRNAs in canine mammary carcinomas / Expressão de LIN28A/B e Let-7 miRNAs em carcinomas mamários caninos

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.

Effect and molecular mechanism of Lin28 on 5-Fu sensitivity of hepatocellular carcinoma HepG2 cells / 中国肿瘤生物治疗杂志

@# 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.

Expression of Lin28B in the placenta of severe preeclampsia and its clinical significance / 中国实用妇科与产科杂志

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.

Antiproliferative effect of urolithin A, the ellagic acid-derived colonic metabolite, on hepatocellular carcinoma HepG2. 2. 15 cells by targeting Lin28a/let-7a axis

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.

Lin28B/let-7d axis contributes to pulmonary fibrosis by affecting mesenchymal phenotypic properties of lung fibroblasts / 中国药理学通报

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.

Clinicopathological Characteristics of Patients with Gastric Cancer according to the Expression of LIN28A

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.

The experimentation about the expression of Lin28b and its clinical relevance in Pancreatic cancer / 中国医师杂志

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.

Unlocking the Neurogenic Potential of Mammalian Müller Glia

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.

Biogenesis and regulation of the let-7 miRNAs and their functional implications

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.

CCL18 downregulates the expression of miR98 in breast cancer cells via N-Ras/c-myc/lin28 pathway / 西安交通大学学报(医学版)

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.

The progress on genes associated with early puberty / 国际儿科学杂志

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.-

Expression of tumor stem cell markers in the tumor sphere from esophageal squamous cells carcinoma Eca109 / 解剖学报

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 .

Let-7i regulates glioma U251 stem cell differentiation through LIN28 protein / 中华神经医学杂志

Objective To investigate the effect of MicroRNA (miRNA) let-7i on differentiation ofglioma U251 stem cells and the potential mechanisms.Methods Glioma U251 cells were cultured in vitro and CD133 positive cells were sorted by magnetic cell separation.Composite let-7i mimics and let-7i controls were transfected into U251 cells; the let-7i expression was detected by real time-PCR; the expressions ofCD133,nestin and LIN28 were detected by Western blotting; the differentiation status was assessed via glial fibrillary acidic protein (GFAP) immunocytochemistry.Composite LIN28 siRNA and siRNA control were transfected into U251 cells; the expressions of CD133 and nestin were detected by Western blotting.Targetscan software analysis and luciferase reporter system were employed to verified the possibility of LIN28 being the target gene of let-7i.Results let-7i in the U251 cells were over-expressed in group of let-7i mimics,enjoying 17.9 fold of group of let-7i control; the expressions of CD 133,nestin and LIN28 were 13.9％,43.7％ and 53.6％,separately,of group of let-7i control; GFAP positive labeling index in group oflet-7i mimics (83.0±1.93)％ was significantly higher than that of group oflet-7i control (39.7±6.73)％ (P＜0.05).The expressions of CD133 and nestin in group of LIN28 siRNA decreased to 23.7％ and 37.9％ of those in groups of siRNA control.LIN28 3'UTR existed let-7i paired binding sites and LIN28 could be the target gene of let-7i.Conclusion over-expressing let-7i could significantly down-regulate the expressions of CD133 and nestin,and enhance the glioma stem cell differentiation through the potential mechanism of down-regulating the expression of LIN28.

Influence and mechanism of obesity on the onset of pubertal development in obese children / 中华实用儿科临床杂志

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.