Advances in research of Musashi2 in solid tumors / 南方医科大学学报

RNA binding protein (RBP) plays a key role in gene regulation and participate in RNA translation, modification, splicing, transport and other important biological processes. Studies have shown that abnormal expression of RBP is associated with a variety of diseases. The Musashi (Msi) family of mammals is an evolutionarily conserved and powerful RBP, whose members Msi1 and Msi2 play important roles in the regulation of stem cell activity and tumor development. The Msi family members regulate a variety of biological processes by binding and regulating mRNA translation, stability and downstream cell signaling pathways, and among them, Msi2 is closely related to embryonic growth and development, maintenance of tumor stem cells and development of hematological tumors. Accumulating evidence has shown that Msi2 also plays a crucial role in the development of solid tumors, mainly by affecting the proliferation, invasion, metastasis and drug resistance of tumors, involving Wnt/β-catenin, TGF-β/SMAD3, Akt/mTOR, JAK/STAT, Numb and their related signaling pathways (Notch, p53, and Hedgehog pathway). Preclinical studies of Msi2 gene as a therapeutic target for tumor have achieved preliminary results. This review summarizes the molecular structure, physiological function, role of Msi2 in the development and progression of various solid tumors and the signaling pathways involved.

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.

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 of PAIP1 on the metastatic potential and prognostic significance in oral squamous cell carcinoma / 国际口腔科学杂志·英文版

Poly Adenylate Binding Protein Interacting protein 1 (PAIP1) plays a critical role in translation initiation and is associated with the several cancer types. However, its function and clinical significance have not yet been described in oral squamous cell carcinoma (OSCC) and its associated features like lymph node metastasis (LNM). Here, we used the data available from Gene Expression Omnibus (GEO), The Cancer Genome Atlas (TCGA), and Clinical Proteomic Tumor Analysis Consortium (CPTAC) to analyze PAIP1 expression in oral cancer. The publicly available data suggests that PAIP1 mRNA and protein levels were increased in OSCC. The high PAIP1 expression was more evident in samples with advanced stage, LNM, and worse pattern of invasion. Moreover, the in vitro experiments revealed that PAIP1 knockdown attenuated colony forming, the aggressiveness of OSCC cell lines, decreasing MMP9 activity and SRC phosphorylation. Importantly, we found a correlation between PAIP1 and pSRC through the analysis of the IHC scores and CPTAC data in patient samples. Our findings suggest that PAIP1 could be an independent prognostic factor in OSCC with LNM and a suitable therapeutic target to improve OSCC patient outcomes.

Analysis of ADAR gene variant in a Chinese pedigree affected with dyschromatosis symmetrica hereditaria / 中华医学遗传学杂志

OBJECTIVE@#To analyze the clinical features and genetic basis for a Chinese pedigree affected with hereditary dyschromatosis symmetrica hereditaria (DSH).@*METHODS@#Peripheral blood samples of the proband and his mother were collected and subjected to PCR and Sanger sequencing.@*RESULTS@#The patient has conformed to the typical pattern of DSH and manifested with hyperpigmentation, hypo- and hyperpigmentation spots on the back of hands, feet and face. Sanger sequencing confirmed that the proband and his mother have both harbored heterozygous splicing variant c.2762+1G>T in exon 9 of the ADAR gene, which was unreported previously. The same variant was not detected among 100 healthy controls. According to the guidelines of the American College of Medical Genetics and Genomics, the variant was predicted to be pathogenic (PVS1+PM2+PP4).@*CONCLUSION@#The c.2762+1G>T variant of the ADAR gene probably underlay the DSH in this pedigree. Above finding has enriched the spectrum of ADAR gene mutations.

Analysis of a Chinese pedigree affected with dyschromatosis symmetrica hereditaria due to a novel variant of ADAR gene / 中华医学遗传学杂志

OBJECTIVE@#To explore the genetic basis for a Chinese pedigree affected with dyschromatosis symmetrica hereditaria (DSH).@*METHODS@#PCR and Sanger sequencing were carried out for the proband, and suspected variant was validated by Sanger sequencing in the pedigree.@*RESULTS@#The proband was found to harbor a novel variant of c.1352delA (p.N451Mfs*13) of the ADAR (NM_001111) gene. The same variant was found in her affected mother and sister, but not in her unaffected father, uncle, and 100 healthy individual.@*CONCLUSION@#The novel variant of the ADAR gene probably underlay the pathogenesis of DSH in this pedigree.

Bioinformatics-based identification of key genes CDC5L and related pathways in osteosarcoma and Ewing's sarcoma / 中国骨伤

OBJECTIVE@#Osteosarcoma(OS) and Ewing's sarcoma (EWS) are the two most common primary malignant bone tumors in children. The aim of the study was to identify key genes in OS and EWS and investigate their potential pathways.@*METHODS@#Expression profiling (GSE16088 and GSE45544) were obtained from GEO DataSets. Differentially expressed genes were identified using GEO2R and key genes involved in the occurrence of both OS and EWS were selected using venn diagram. Gene ontology and pathway enrichment analyses were performed for the ensembl. Protein-protein interaction (PPI) networks were established by STRING. Further, UCSC was used to predict the transcription factors of the cell division cycke 5-like(CDC5L) gene, and GEPIA was used to analyze the correlation between the transcription factors and the CDC5L gene.@*RESULTS@#The results showed that CDC5L gene was the key gene involved in the pathogenesis of OS and EWS. The gene is mainly involved in mitosis, and is related to RNA metabolism, processing of capped intron-containing pre-mRNA, mRNA and pre-mRNA splicing.@*CONCLUSION@#CDC5L, as a key gene, plays a role in development of OS and EWS, which may be reliable targets for diagnosis and treatment of these primary malignant tumors.

RBM38 Mediates the Proliferation of Acute Myeloid Leukemia Cells HL-60 by Regulating FZD1 mRNA Stability / 中国实验血液学杂志

OBJECTIVE@#To explore the regulatory function of RNA binding motif protein 38 (RBM38) in human acute myeloid leukemia cells HL-60 and its mechanism.@*METHODS@#The lentivirus carriers of overexpressed and knockdown RBM38 were constructed. After HL-60 cells were transfected, Western blot was used to analyze the expression level of RBM38 in HL-60 cells. The cell proliferation and cycle of HL-60 were detected by CCK-8 assay and flow cytometry assay, respectively. RNA immunoprecipitation coupled real-time PCR (RIP-qPCR) was used to detect the combination of RBM38 with mRNAs. Actinomycin D treatment followed by real-time PCR (AcD-qPCR) was used to detect the effect of RBM38 on the stability of target mRNAs.@*RESULTS@#RBM38 in HL-60 cells was overexpressed or inhibited by lentivirus transduction. Overexpressed RBM38 promoted the cell cycle and proliferation of HL-60, while RBM38 knockdown repressed the two processes. RBM38 showed an interaction with FZD1 mRNA and enhancement of its stability.@*CONCLUSION@#RBM38 can regulate cell proliferation of HL-60 by improving the stability of FZD1 mRNA.

RNA-binding protein with serine-rich domain 1 regulates microsatellite instability of uterine corpus endometrial adenocarcinoma

OBJECTIVE: To determine the role of RNA-binding protein with serine-rich domain 1 (RNPS1) in uterine corpus endometrial carcinoma (UCEC), the role of RNPS1 knockdown in UCEC development in vitro and in vivo, and the relationship between RNPS1 and mismatch repair (MMR) in UCEC. METHODS: We predicted the potential function of RNPS1 using bioinformatics systems. The expression of RNPS1 in tissues and cell lines was analyzed by western blotting and immunohistochemistry. The expression of RNPS1 in MMR was assessed using bioinformatics and western blotting. The proliferation and apoptosis of UCEC cells were assessed under RNPS1 knockdown conditions, and RNPS1 regulation in MMR was detected by suppressing Notch signaling. Associations between RNPS1 and gene mutations in UCEC and prognosis were analyzed. RESULTS: The RNPS1 level was higher in UCEC tumors than in normal tissues and tumors or RL952 cells. Prognostic outcomes were worse when UCEC showed abundant RNPS1 expression. Lentiviral RNPS1 knockdown weakened tumor cell proliferation and suppressed biomarker expression, reduced the tumor volume, promoted apoptosis in vitro and in vivo, and inhibited UCEC development. Increased MutS homolog 2 (MSH2) and MutS homolog 6 (MSH6) levels in MMR after RNPS1 knockdown were reversed by inhibiting Notch signaling. Furthermore, RNPS1 was associated with mutations in NAA11, C2orf57, NUPR1, and other genes involved in UCEC prognosis. CONCLUSION: RNPS1 may regulate the expression levels of MSH2 and MSH6 in MMR, enhancing the proliferation, development, and prognosis of UCEC through a Notch signaling pathway in UCEC. Our study offers a new method and strategy for delaying UCEC development through modulating MMR.

Human esophageal fibroblast-derived exosomal miR-21 reduced the cisplatin sensitivity to esophageal carcinoma EC9706 cells

The objective of this study was to investigate the effect of human esophageal fibroblast-derived exosomal miR-21 on cisplatin sensitivity against esophageal squamous EC9706 cells. EC9706 cells were co-cultured indirectly with human esophageal fibroblasts (HEF) or miR-21 mimics transfected-HEF in the transwell system. The exosomes in HEF-culture conditioned medium were extracted by differential ultracentrifugation. EC9706 cells were co-cultured with HEF-derived exosomes directly. The cisplatin sensitivity against EC9706 cells was revealed via half maximal inhibitory concentration (IC50) values using MTT assay. The expressions of miR-21, programmed cell death 4 (PDCD4) mRNA, and gene of phosphate and tension homology deleted on chromosome ten (PTEN) mRNA were determined by qRT-PCR. The changes of the protein level were detected using western blot assay. IC50 values of cisplatin against EC9706 cells were increased after EC9706 cells were co-cultured with either HEF or exosomes derived from miR-21 mimics-transfected HEF. Following the increased level of miR-21, the mRNA expression and protein levels of PTEN and PDCD4 were decreased in EC9706 cells. The cisplatin sensitivity to EC9706 cells was reduced by HEF-derived exosomal miR-21 through targeting PTEN and PDCD4. This study suggested that non-tumor cells in the tumor micro-environment increased the tumor anti-chemotherapy effects through their exosomes.

Regulation of RNA Binding Protein Mbnl1 on Development of Mouse Embryonic Hematopoietic Stem Cells / 中国实验血液学杂志

OBJECTIVE@#To analyze the dynamic molecular expression characteristics of single cell RNA binding proteins (RBPs) in the development of mouse embryonic hematopoitic stem cells (HSCs), and obtain the functional research target RNA splicing factor--Mbnl1, to clarify the function of Mbnl1 involved in regulating mouse embryonic HSC development.@*METHODS@#Bioinformatics was used to analyze the single-cell transcriptome data of mouse embryos during HSC development, and the single-cell RBP dynamic molecular expression maps in HSC development was obtained. Mbnl1 was obtained by combining differential analysis and literature research screening. The Mbnl1-knockout mouse model was constructed by the CRISPER/Cas9 technology. Aorta-gonad-mesonephros (AGM) and yolk sac (YS) tissue in two genotype embryos of Mbnl1@*RESULTS@#The in vitro CFU-C experiment of hematopoietic cells preliminarily indicated that there was no significant difference in the number of cell colonies in AGM region and YS transformed by the two genotypes of Mbnl1@*CONCLUSION@#Through functional experiments in vivo and in vitro, it has been confirmed that knockout of the RNA splicing factor--Mbnl1 does not affect the development of HSPC in AGM region of mouse embryo.

RNA Binding Protein RBM47 Inhibits the K562 Cell Proliferation by Regulating HMGA2 mRNA Expression / 中国实验血液学杂志

OBJECTIVE@#To investigate the regulatory effects of RBM47 on HMGA2 and the function of RBM47 in human chronic myeloid leukemia cell K562.@*METHODS@#K562 cells were transduction by the overexpressed and knockdown RBM47 lentiviral vector. CCK-8 assay was used to detect the effect of RBM47 on the proliferation of K562 cells. Flow cytometry assay was used to detect the effect of RBM47 on the cell cycle progression of K562 cells. RNA immunoprecipitation assay was used to detect the association between RBM47 and HMGA2 mRNA. RT-qPCR was used to detect the effects of RBM47 on the stability of HMGA2 mRNA. Western blot was used to evaluate the effect of RBM47 on HMGA2 protein expression.@*RESULTS@#The overexpressed RBM47 could inhibit the proliferation and cell cycle progression of K562 cells. However, the inhibitation of RBM47 could improve the proliferation and cell cycle progression of K562 cells. RBM47 combined with HMGA2 mRNA could promote the degradation of HMGA2 mRNA. Thus, the overexpressed RBM47 could decrease the expression of HMGA2 protein in K562 cells.@*CONCLUSION@#RNA binding protein RBM47 can inhibit the proliferation of K562 cells by regulating HMGA2 expression.

7SK truncation at 128-179 nt suppresses embryonic stem cell proliferation / 南方医科大学学报

OBJECTIVE@#To explore the role of small nuclear noncoding RNA 7SK in embryonic stem cell (ESCs) proliferation and the value of 7SK as a target for early diagnosis and treatment for primordial dwarfism (PD).@*METHODS@#ESC line R1 was transfected with the CRISPR/Cas9 system, and sequencing of the PCR product and glycerol gradient analysis were performed to identify novel 7SK deletion mutations. A lentivirus system was used to knock down cyclin-dependent kinase 9 (CDK9) in clones with 7SK deletion mutations, and the effect of CDK9 knockdown on the protein level of cell division cycle 6 (CDC6) was analyzed with Western blotting.@*RESULTS@#We identified a novel deletion mutation of 7SK at 128-179 nt in the ESCs, which resulted in deficiency of cell proliferation. 7SK truncation at 128-179 nt significantly reduced the protein expressions of La-related protein 7 (LARP7) and CDC6.@*CONCLUSIONS@#7SK truncation at 128-179 nt can significantly impair proliferation of ESCs by downregulating CDC6. 7SK is a key regulator of proliferation and mediates the growth of ESCs through a mechanism dependent on CDK9 activity, suggesting the value of 7SK truncation at 128-179 nt as a potential target for early diagnosis and treatment of PD.

Improvement of polyhydroxybutyrate production by deletion of csrA in Escherichia coli

BACKGROUND: Poly-3-hydroxybutyrate (PHB) can be efficiently produced in recombinant Escherichia coli by the overexpression of an operon (NphaCAB) encoding PHB synthetase. Strain improvement is considered to be one of critical factors to lower the production cost of PHB in recombinant system. In this study, one of key regulators that affect the cell growth and PHB content was confirmed and analyzed. RESULT: S17-3, a mutant E. coli strain derived from S17-1, was found to be able to achieve high cell density when expressing NphaCAB with the plasmid pBhya-CAB. Whole genome sequencing of S17-3 revealed genetic alternations on the upstream regions of csrA, encoding a global regulator cross-talking between stress response, catabolite repression and other metabolic activities. Deletion of csrA or expression of mutant csrA resulted in improved cell density and PHB content. CONCLUSION: The impact of gene deletion of csrA was determined, dysfunction of the regulators improved the cell density of recombinant E. coli and PHB production, however, the detail mechanism needs to be further clarified.

Tumor suppressive function of Matrin 3 in the basal-like breast cancer

BACKGROUND: Basal-like breast cancer (BLBC) or triple-negative breast cancer (TNBC) is an aggressive and highly metastatic subtype of human breast cancer. The present study aimed to elucidate the potential tumor-suppressive function of MATR3, an abundant nuclear protein, in BLBC/TNBC, whose cancer-relevance has not been characterized. METHODS: We analyzed in vitro tumorigenecity by cell proliferation and soft agar colony formation assays, apoptotic cell death by flow cytometry and Poly (ADP-ribose) polymerase (PARP) cleavage, epithelial-mesenchymal transition (EMT) by checking specific EMT markers with real-time quantitative PCR and in vitro migration and invasion by Boyden Chamber assays. To elucidate the underlying mechanism by which MATR3 functions as a tumor suppressor, we performed Tandem affinity purification followed by mass spectrometry (TAP-MS) and pathway analysis. We also scrutinized MATR3 expression levels in the different subtypes of human breast cancer and the correlation between MATR3 expression and patient survival by bioinformatic analyses of publicly available transcriptome datasets. RESULTS: MATR3 suppressed in vitro tumorigenecity, promoted apoptotic cell death and inhibited EMT, migration, and invasion in BLBC/TNBC cells. Various proteins regulating apoptosis were identified as MATR3-binding proteins, and YAP/TAZ pathway was suppressed by MATR3. MATR3 expression was inversely correlated with the aggressive and metastatic nature of breast cancer. Moreover, high expression levels of MATR3 were associated with a good prognosis of breast cancer patients. CONCLUSIONS: Our data demonstrate that MATR3 functions as a putative tumor suppressor in BLBC/TNBC cells. Also, MATR3 potentially plays a role as a biomarker in predicting chemotherapy-sensitivity and patient survival in breast cancer patients.

MiR-128 suppresses metastatic capacity by targeting metadherin in breast cancer cells

BACKGROUND: Breast cancer, the most common cancer in women worldwide, causes the vast majority of cancer-related deaths. Undoubtedly, tumor metastasis and recurrence are responsible for more than 90 percent of these deaths. MicroRNAs are endogenous noncoding RNAs that have been integrated into almost all the physiological and pathological processes, including metastasis. In the present study, the role of miR-128 in breast cancer was investigated. RESULTS: Compared to the corresponding adjacent normal tissue, the expression of miR-128 was significantly suppressed in human breast cancer specimens. More importantly, its expression level was reversely correlated to histological grade of the cancer. Ectopic expression of miR-128 in the aggressive breast cancer cell line MDA-MB-231 could inhibit cell motility and invasive capacity remarkably. Afterwards, Metadherin (MTDH), also known as AEG-1 (Astrocyte Elevated Gene 1) and Lyric that implicated in various aspects of cancer progression and metastasis, was further identified as a direct target gene of miR-128 and its expression level was up-regulated in clinical samples as expected. Moreover, knockdown of MTDH in MDA-MB-231 cells obviously impaired the migration and invasion capabilities, whereas re-expression of MTDH abrogated the suppressive effect caused by miR-128. CONCLUSIONS: Overall, these findings demonstrate that miR-128 could serve as a novel biomarker for breast cancer metastasis and a potent target for treatment in the future.

Prognostic value of increased expression of RBM8A in gastric cancer

This study was designed to investigate the expression of RBM8A protein in patients with gastric cancer (GC) and to explore its correlation with clinical pathological features as well as prognosis. One hundred pairs of gastric carcinoma tissues and adjacent tissues from patients undergoing gastrectomy for GC were included in this study. The protein expression level of RBM8A was determined by immunohistochemistry using tissue microarrays. We also detected the mRNA expression level of RBM8A in 16 pairs of gastric carcinoma tissues and adjacent tissues. Meanwhile, we predicted the potential correlation between RBM8A and tumor stages as well as survival condition in patents with GC based on The Cancer Genome Atlas (TCGA) database. The correlation of RBM8A with the clinical pathological features and prognosis of the 100 patients with GC was also elucidated. The expression level of RBM8A was significantly higher in gastric carcinoma tissues compared to the adjacent tissues. The protein level of RBM8A was correlated with tumor size (P=0.031), depth of invasion (P<0.001), lymph node metastasis (P<0.001), TNM stage (<0.001), and distant metastasis (P=0.001). Patients with increased RBM8A expression (P<0.0018, 95%CI=0.322−0.871), higher TNM stage (P<0.001, 95%CI=4.990−11.283), and lymph node metastasis (P<0.001, 95%CI=2.873−4.002) had a lower overall survival. Taken together, our study demonstrated that RBM8A may act as a proto-oncogene, which could be a promising biomarker and therapeutic target in the diagnosis and treatment of GC.

Effect of CPEB4 on Migration and Cycle of Chronic Myeloid Leukemia Cell / 中国实验血液学杂志

OBJECTIVE@#To investigate the effects of CPEB4 on the migration and cycle of K562 cells and the changes of protein molecules that may be involved in the regulatory mechanism.@*METHODS@#Western blot was used to detect the expression of CPEB4 in normal leukocytes and K562 cells. The overexpression plasmid pcDNA3.1(+)-His-CPEB4, silencing plasmid pPLK+Puro-CPEB4 shRNA were transfected into K562 cells by electroporation so as to change CPEB4. The transfection efficiency was detected by Western blot. Finally, the migration and cycle of different cells were detected by Transwell chamber and flow cytometry.Western blot was used to detect the expression changes of MMP2, MMP9, CDK4, CyclinD1 and P21 proteins.@*RESULTS@#Compared with normal white blood cells, the expression of CPEB4 protein in K562 cells was significantly enhanced (P＜0.01); Compared with the control group, CPEB4-silenced K562 cells showed that the cell migration ability was significantly enhanced (P＜0.01); G/G phase cell ratio reduced, G/M phase cell ratio increased, and cell cycle progression accelerated（P＜0.01）, The expression levels of MMP2 (P＜0.05), MMP9 (P＜0.05), CDK4 (P＜0.01), CyclinD1 (P＜0.01) proteins increased significantly. The expression level of P21 protein significantly decreased (P＜0.01). The migration ability of K562 cells after CPEB4 overexpression was decreased (P＜0.01), the cell ratio of G/G phase in the cell cycle increased, the cell proportion of S phase decreased and the cell cycle progression was arrested at G/G phase (P＜0.01). The expression of P21 protein increased, MMP2 , MMP9, CDK4, CyclinD1 protein expression decreased significantly（P＜0.05-0.01）.@*CONCLUSION@#CPEB4 can inhibit the migration of K562 cells and arrest cell cycle progression at G/G phase. Its mechanism may be related with regulating the exprossion of MMP2, MMP9, CDK4, CyclinD1 and P21 proteins.

Posttranscriptional control of intestinal epithelium homeostasis by RNA-binding protein HuR / 生理学报

The mammalian intestinal epithelium is a rapidly self-renewing tissue in the body and directly interfaces with a wide array of luminal noxious contents and microorganisms. Homeostasis of the intestinal epithelium is preserved through well-controlled mechanisms including posttranscriptional regulation. RNA-binding protein (RBP) HuR regulates the stability and translation of target mRNAs and is intimately involved in many aspects of gut mucosal pathophysiology. Here we highlight the biological roles of HuR in maintaining the integrity of the intestinal epithelium, with particular focus on the emerging evidence of HuR in the regulation of intestinal epithelial renewal, mucosal repair, defense, and gut permeability. We also further analyze the mechanisms through which HuR and its interactions with other RBPs and noncoding RNAs (ncRNAs) such as microRNAs and long ncRNAs modulate the intestinal epithelial homeostasis. With rapidly advancing knowledge of RBPs and ncRNAs, there is growing recognition that posttranscriptional control of the intestinal epithelium homeostasis might be promising therapeutic targets in our efforts to protect the integrity of the intestinal epithelium under critical pathological conditions.

Analysis of ADAR1 gene variants in two pedigrees affected with dyschromatosis symmetrica hereditaria / 中华医学遗传学杂志

OBJECTIVE@#To detect variants of ADAR1 gene in two Chinese pedigrees affected with dyschromatosis symmetrica hereditaria (DSH).@*METHODS@#Clinical data and peripheral blood samples of the pedigrees were collected. All exons of the ADAR1 gene were amplified by PCR and subjected to Sanger sequencing. Suspected pathogenic variants were validated among other members of the pedigrees and 100 unrelated healthy controls.@*RESULTS@#For pedigree 1, Sanger sequencing has identified a heterozygous missense variant c.3002G>C (p.Asp968His) in exon 11 of the ADAR1 gene in the proband and his father. For pedigree 2, a novel nonsense variant c.3145C>T (p.Gln1049Ter) was identified in exon 12 of the ADAR1 gene in the proband and his son, which were previously unreported and absent among the healthy controls.@*CONCLUSION@#The c.3002G>C (p.Asp968His) and c.3145C>T (p.Gln1049Ter)variants of the ADAR1 gene probably underlay the DSH in the two pedigrees.