Objective To establish stable prostate cancer bone metastasis cell line overexpressing microRAN-145 (miR-145)for the study of the mechanism of miR-145 in bone metastasis.Methods pMSCV-miR-145 plasmids and retroviruses...Objective To establish stable prostate cancer bone metastasis cell line overexpressing microRAN-145 (miR-145)for the study of the mechanism of miR-145 in bone metastasis.Methods pMSCV-miR-145 plasmids and retroviruses of pMSCV-vector展开更多
By PCR method, apo phycoerythrocyanin α subunit gene (pecA) of Mastigocladus laminosus (M. laminosus) was amplified from its genomic DNA, and then cloned in pBluescript. The pecA gene was subcloned into the exp...By PCR method, apo phycoerythrocyanin α subunit gene (pecA) of Mastigocladus laminosus (M. laminosus) was amplified from its genomic DNA, and then cloned in pBluescript. The pecA gene was subcloned into the expression vector pGEMD, and then transformed into E.coli BL21 (DE3). After induction, a new protein of molecular weight 19×10 3 existing in inclusion body was overexpressed. The expressed product was confirmed to be apo phycoerythrocyanin α subunit by Dot ELISA.展开更多
Carotenoids act as precursors of vitamin A,antioxidants,enhancers of immunity,and are thus widely used in food and pharmaceutical industry.Microbial fermentation is one of the most important solutions for production o...Carotenoids act as precursors of vitamin A,antioxidants,enhancers of immunity,and are thus widely used in food and pharmaceutical industry.Microbial fermentation is one of the most important solutions for production of natural carotenoids.Rhodobacter sphaeroides is one of most promising bacteria employed for large scale production of carotenoids.In the present study,crtA located in the carotenoids biosynthesis pathway in R.sphaeroides was amplified by PCR.The overexpression vector pRKcrtA was constructed and subsequently transferred into R.sphaeroides,producing the genetically engineered strain R.sphaeroides 2.4.1/pRKcrtA overexpressing crtA.The carotenoid production from the genetically engineered strain was significantly increased.Fermentation procedure was optimized for further enhanced carotenoids production.展开更多
Castor is one of the top 10 oil crops in the world and has extremely valuable uses.Castor inflorescences directly affect yield,so the study of inflorescence development is very important in increasing castor yield.Our...Castor is one of the top 10 oil crops in the world and has extremely valuable uses.Castor inflorescences directly affect yield,so the study of inflorescence development is very important in increasing castor yield.Our previous studies have shown that the PIP5K gene family(PIP5Ks)is associated with inflorescence development.In this study,to determine the function of each PIP5K gene in castor,a female Lm-type castor line,aLmAB2,was used to determine the relative expression levels of the PIP5Ks in castor inflorescences.Six PIP5K genes were heterologously overexpressed in Arabidopsis thaliana,the relative expression of each gene and the effect on plants was determined in A.thaliana,and the relationships among the PIP5Ks in castor were inferred.The expression levels of the PIP5Ks in the female Lm-type castor line aLmAB2 were analyzed.The relative expression levels of the PIP5K9 and PIP5K11 genes were high(p<0.05)in isofemale inflorescences,and those of PIP5K1,PIP5K2,PIP5K6,and PIP5K8 were high(p<0.05)in female inflorescences but low(p<0.05)in bisexual inflorescences.The PIP5Ks were heterologously overexpressed in A.thaliana,and T3-generation plants with stable genetic resistance,i.e.,AT-PIP5K^(+)plants(AT-PIP5K1^(+),AT-PIP5K2^(+),AT-PIP5K6^(+),AT-PIP5K8^(+),AT-PIP5K9^(+),and ATPIP5K11^(+) plants),were obtained.Biological tests of the AT-PIP5K+plants showed that the growth of the main stem was significantly delayed in AT-PIP5K+plants compared with Columbia wild-type(WT)A.thaliana plants;the PIP5K1 and PIP5K2 genes promoted lateral stem growth and flower and silique development;and the PIP5K6,PIP5K8,PIP5K9 and PIP5K11 genes inhibited lateral stem growth and flower and silique development.The correlations among PIP5Ks in castor suggest that there may be a synergistic relationship among PIP5K1,PIP5K2,and PIP5K6 in castor inflorescences,and PIP5K8,PIP5K9,and PIP5K11 are complementary to the other three genes.展开更多
Downregulation of the inwardly rectifying potassium channel Kir4.1 is a key step for inducing retinal Müller cell activation and interaction with other glial cells,which is involved in retinal ganglion cell apopt...Downregulation of the inwardly rectifying potassium channel Kir4.1 is a key step for inducing retinal Müller cell activation and interaction with other glial cells,which is involved in retinal ganglion cell apoptosis in glaucoma.Modulation of Kir4.1 expression in Müller cells may therefore be a potential strategy for attenuating retinal ganglion cell damage in glaucoma.In this study,we identified seven predicted phosphorylation sites in Kir4.1 and constructed lentiviral expression systems expressing Kir4.1 mutated at each site to prevent phosphorylation.Following this,we treated Müller glial cells in vitro and in vivo with the m Glu R I agonist DHPG to induce Kir4.1 or Kir4.1 Tyr^(9)Asp overexpression.We found that both Kir4.1 and Kir4.1 Tyr^(9)Asp overexpression inhibited activation of Müller glial cells.Subsequently,we established a rat model of chronic ocular hypertension by injecting microbeads into the anterior chamber and overexpressed Kir4.1 or Kir4.1 Tyr^(9)Asp in the eye,and observed similar results in Müller cells in vivo as those seen in vitro.Both Kir4.1 and Kir4.1 Tyr^(9)Asp overexpression inhibited Müller cell activation,regulated the balance of Bax/Bcl-2,and reduced the m RNA and protein levels of pro-inflammatory factors,including interleukin-1βand tumor necrosis factor-α.Furthermore,we investigated the regulatory effects of Kir4.1 and Kir4.1 Tyr^(9)Asp overexpression on the release of pro-inflammatory factors in a co-culture system of Müller glial cells and microglia.In this co-culture system,we observed elevated adenosine triphosphate concentrations in activated Müller cells,increased levels of translocator protein(a marker of microglial activation),and elevated interleukin-1βm RNA and protein levels in microglia induced by activated Müller cells.These changes could be reversed by Kir4.1 and Kir4.1 Tyr^(9)Asp overexpression in Müller cells.Kir4.1 overexpression,but not Kir4.1 Tyr^(9)Asp overexpression,reduced the number of proliferative and migratory microglia induced by activated Müller cells.Collectively,these results suggest that the tyrosine residue at position nine in Kir4.1 may serve as a functional modulation site in the retina in an experimental model of glaucoma.Kir4.1 and Kir4.1 Tyr^(9)Asp overexpression attenuated Müller cell activation,reduced ATP/P2X receptor–mediated interactions between glial cells,inhibited microglial activation,and decreased the synthesis and release of pro-inflammatory factors,consequently ameliorating retinal ganglion cell apoptosis in glaucoma.展开更多
The published article titled“Truncated Bid Overexpression Induced by Recombinant Adenovirus Cre/LoxP System Suppresses the Tumorigenic Potential of CD133+Ovarian Cancer Stem Cells”has been retracted from Oncology Re...The published article titled“Truncated Bid Overexpression Induced by Recombinant Adenovirus Cre/LoxP System Suppresses the Tumorigenic Potential of CD133+Ovarian Cancer Stem Cells”has been retracted from Oncology Research,Vol.25,No.4,2017,pp.595–603.展开更多
Phytase genephyA2, whose signal peptide encoding sequence and intron sequence had been removed, was modified. The Arg-encoding codons CGG and CAG inphyA2 were mutated into synonymous codon AGA. The modifiedphyA2 was f...Phytase genephyA2, whose signal peptide encoding sequence and intron sequence had been removed, was modified. The Arg-encoding codons CGG and CAG inphyA2 were mutated into synonymous codon AGA. The modifiedphyA2 was fused behind a-factor signal sequence under the control ofAOX1 promoter in plasmid pPIC9, then introduced into the hostPichia pastoris by electroporation. The results of Southern blotting analysis and Northem blotting analysis demonstrated that thephyA2 gene had integrated into the genome ofP. pastoris and transcribed. The result of SDS-PAGE of the phytase expressed by P.pastoris showed that the modifiedphyA2 had been overexpressed and secreted. The concentration of the phytase expressed by P.pastoris with modifiedphyA2 exceeded 15 000 U/mL, which had a 3 000-fold increase over that of originAspergillus niger 963 and was 37 times higher than that of recombinantP. pastoris with non-modifiedphyA2.展开更多
Modulating Tankyrases(TNKS),interactions with USP25 to promote TNKS degradation,rather than inhibiting their enzymatic activities,is emerging as an alternative/specific approach to inhibit the Wnt/β-catenin pathway.H...Modulating Tankyrases(TNKS),interactions with USP25 to promote TNKS degradation,rather than inhibiting their enzymatic activities,is emerging as an alternative/specific approach to inhibit the Wnt/β-catenin pathway.Here,we identified UAT-B,a novel neoantimycin analog isolated from Streptomyces conglobatus,as a small-molecule inhibitor of TNKS-USP25 protein-protein interaction(PPI)to overcome multi-drug resistance in colorectal cancer(CRC).The disruption of TNKS-USP25 complex formation by UAT-B led to a significant decrease in TNKS levels,triggering cell apoptosis through modulation of the Wnt/β-catenin pathway.Importantly,UAT-B successfully inhibited the CRC cells growth that harbored high TNKS levels,as demonstrated in various in vitro and in vivo studies utilizing cell line-based and patient-derived xenografts,as well as APC^(min/+)spontaneous CRC models.Collectively,these findings suggest that targeting the TNKS-USP25 PPI using a small-molecule inhibitor represents a compelling therapeutic strategy for CRC treatment,and UAT-B emerges as a promising candidate for further preclinical and clinical investigations.展开更多
Correction to:Neurosci.Bull.December,2016,32(6):577–584.https://doi.org/10.1007/s12264-016-0068-z In this article,in Fig 5A,the picture of the Vector+Nogo-66 group was incorrect and should have appeared as shown below.
The published article titled“Overexpression of miR-1283 Inhibits Cell Proliferation and Invasion of Glioma Cells by Targeting ATF4”has been retracted from Oncology Research,Vol.27,No.3,2019,pp.325–334.
Drought and salt stresses are major abiotic factors that severely affect the growth,development,and yield formation of Brassica napus.Human derived FTO gene(Fat mass and obesity-associated),is a member of the Alk B fa...Drought and salt stresses are major abiotic factors that severely affect the growth,development,and yield formation of Brassica napus.Human derived FTO gene(Fat mass and obesity-associated),is a member of the Alk B family,encoding a m RNA demethylase that is dependent onα-ketoglutarate.Although previous studies have demonstrated that exogenous overexpression of FTO gene can increase plant biomass,its impact on plant stress resistance is still unclear.In this study,we cloned the FTO gene and conducted an analysis of its biological functions for drought and salt resistance for Brassicaceae plants.By overexpressing the FTO gene in Arabidopsis thaliana,the inhibitory effect of salt and drought stress on the root length growth of transgenic lines was significantly lower than that of the control.Moreover,the overexpression of FTO markedly enhanced the tolerance of Arabidopsis to drought and salt stress.It also led to a decrease in malondialdehyde(MDA)content,an increase in proline content,and a boost in superoxide dismutase(SOD)activity.Meanwhile,when the FTO gene was heterologously expressed in B.napus,the transgenic plants were less affected by stress.In comparison to control plants,they exhibited significantly lower MDA levels and markedly higher proline content and SOD activity.Furthermore,staining results with Trypan blue and nitroblue tetrazolium(NBT)staining indicate that the FTO gene can alleviate the damage to plants under stress and inhibit the accumulation of O_(2)^(-).Comprehensively,the results indicate that overexpression of the FTO gene can improve the drought and salt tolerance in transgenic plants,providing valuable references for further exploring the FTO-mediated stress resistance mechanisms.展开更多
A polyketide synthase-nonribosomal peptide synthetase gene cluster twn in Talaromyces sp.HDN1820200 was activated by overexpression of the pathway-specific transcriptional factor TwnD.Large-scale fermentation and chem...A polyketide synthase-nonribosomal peptide synthetase gene cluster twn in Talaromyces sp.HDN1820200 was activated by overexpression of the pathway-specific transcriptional factor TwnD.Large-scale fermentation and chemical investigation of the mutant strain HDN1820200/TwnD led to the discovery of one new polyketide-amino acid conjugate,bipolamide C and one new polyketide compound,variotin A.The structures of the new compounds were determined by nuclear magnetic resonance(NMR)analysis,high-resolution electrospray ionization mass spectrometry,feeding experiments,NMR calculation and DP4^(+)analysis.This study revealed that the overexpression of the pathway-specific transcriptional factor represents a promising approach for the discovery of new natural products in fungi within specialized habitat.展开更多
A 1 539 by squalene synthase (AaSQS) cDNA was cloned from a high-yield Artemisia annua L. strain 001 by reverse transcription-polymerise chain reaction (RT-PCR). The amino acid sequence of AaSQS is 70%, 77%, 44% and 3...A 1 539 by squalene synthase (AaSQS) cDNA was cloned from a high-yield Artemisia annua L. strain 001 by reverse transcription-polymerise chain reaction (RT-PCR). The amino acid sequence of AaSQS is 70%, 77%, 44% and 39%a identical to that of squalene synthases from Arabidopsis thaliana, tobacco, human and yeast, respectively. The AaSQS genomic DNA has a complex organization containing 14 exons and 13 introns. Full-length or C-terminal truncated cDNA was subcloned into prokaryotic expression vector pET30a and the constructed plasmid was introduced to Escherichia coli strain BL21 (DE3) for induced overexpression. No squalene synthase protein with expected molecular mass was observed in E. cola containing the putative full-length squalene synthase cDNA, however, overexpression in E. coli was achieved by truncating 30 amino acids of hydrophobic region at the carboxy terminus.展开更多
Methyl jasmonate (MeJA) is a plant-signaling molecule that regulates plant morphogenesis and expression of plant defense genes. To determine the role of the endogenous MeJA levels in the development of plants, trans...Methyl jasmonate (MeJA) is a plant-signaling molecule that regulates plant morphogenesis and expression of plant defense genes. To determine the role of the endogenous MeJA levels in the development of plants, transgenic soybean [Glycine max (L.) Merrill] plants harboring NTR1 gene encoding for jasmonic acid carboxyl methyltransferase (JMT) were produced. The activation of NTR1 gene expression resulted in the production of MeJA. Overexpression of the NTR1 cDNA under the regulation of cauliflower mosaic virus (CaMV) 35S promoter in the transgenic soybean plants was confirmed using Northern blot analysis. The significant differences in leaf and root growth patterns were observed between the transgenic plants and the wild-type plants. The leaves of the transgenic plants were slightly elongated in length but dramatically narrowed in width compared with the nontrans-formed wild-type plants. In addition, elongation of primary root was inhibited in the overexpressed transgenic soybean plantlets, whereas the development of lateral root was stimulated relative to the nontransformed plants. The leaves of the transgenic plants showed 2-2.5-fold higher levels of MeJA than the control plants. These results indicated that the increased endogenous levels of MeJA is involved in regulation of morphogenesis in soybean plants.展开更多
Background:Fatty acid(FA) composition is the most important parameter affecting the flavor and nutritional value of the meat.The final and the only committed step in the biosynthesis of triglycerides is catalyzed b...Background:Fatty acid(FA) composition is the most important parameter affecting the flavor and nutritional value of the meat.The final and the only committed step in the biosynthesis of triglycerides is catalyzed by diacylglycerol acyltransferase 2(DGAT2).The role of DGAT2 in lipid accumulation has been demonstrated in adipocytes,However,little is known about the effect of DGAT2 on the FA composition of these cells.Methods:To investigate the role of DGAT2 in regulating lipid accumulation,FA composition and the expression of adipogenic genes,we cloned the open reading frame of the porcine DGAT2 gene and established 3T3-L1 cells that overexpressed DGAT2.Cells were then cultured in differentiation medium(DM) without FA,with a mixture of FAs(FA-DM),or containing a ^(13)C stable isotope-labeled FA mixture(IFA-DM).The FA composition of adipocytes was analyzed by gas chromatography-mass spectrometry and gas chromatography-isotope ratio mass spectrometry.Quantitative PCR and western blotting were employed to detect expression of adipogenic genes in 3T3-L1 adipocytes cultured with FA-DM for 12 d.Results:The triacylglyceride(TAG) content was significantly higher in 3T3-L1 adipocytes overexpressing DGAT2 than in control cells.When cultured in DM or FA-DM for 12 d,cells overexpressing DGAT2 showed a higher proportion of unsaturated FAs(C16:1 and C18:1).However,when cells overexpressing DGAT2 were cultured with FA-DM for30 min,the FA composition was almost identical to that of controls.Further,the proportion of stable isotope-labeled FAs were similar in 3T3-L1 adipocytes overexpressing DGAT2 and control cells cultured in IFA-DM for 12 d.These results collectively indicate that the higher proportion of mono-unsaturated FAs,C16:1 and C18:1,may originate from de novo FA synthesis but not from the uptake of specific FAs from the medium.This hypothesis is further supported by evidence that both mRNA and protein expression of genes involved in FA synthesis(ACACA,FASN,SCD1,and A-FABP)were significantly higher in cells overexpressing DGAT2 than in control cells.Conclusions:In conclusion,our study revealed that TAG accumulation,the proportion of MUFAs,and the expression of adipogenic genes were higher in 3T3-L1 cells overexpressing DGAT2 than in control cells.展开更多
AIM:To investigate the role of the overexpression of B7-H3 in apoptosis in colorectal cancer cell lines and the underlying molecular mechanisms.METHODS:SW620 cells that highly overexpressed B7-H3(SW620-B7-H3-EGFP)and ...AIM:To investigate the role of the overexpression of B7-H3 in apoptosis in colorectal cancer cell lines and the underlying molecular mechanisms.METHODS:SW620 cells that highly overexpressed B7-H3(SW620-B7-H3-EGFP)and HCT8 cells stably transfected with B7-H3 sh RNA(HCT8-sh B7-H3)were previously constructed in our laboratory.Cells transfected with p IRES2-EGFP were used as negative controls(SW620-NC and HCT8-NC).Real-time PCR and western blotting analysis were used to detect the m RNA and protein expressions of the apoptosis regulator proteins Bcl-2,Bcl-xl and Bax.A cell proliferation assay was used to evaluate the survival rate and drug sensitivity of the cells.The effect of drug resistance was detected by a cell cycle assay.Active caspase-3western blotting was used to reflect the anti-apoptotic ability of cells.Western blotting was also performed to determine the expression of proteins associated with the Jak2-STAT3 signaling pathway and the apoptosis regulator proteins after the treatment with AG490,a Jak2 specific inhibitor,in B7-H3 overexpressing cells.The data were analyzed by Graph Pad Prism 6 using a non-paired t-test.RESULTS:Whether by overexpression in SW620cells or downregulation in HCT8,B7-H3 significantly affected the expression of anti-and pro-apoptotic proteins,at both the transcriptional and translational levels,compared with the negative control(P<0.05).A cell proliferation assay revealed that B7-H3overexpression increased the drug resistance of cells and resulted in a higher survival rate(P<0.05).In addition,the results of cell cycle and active caspase-3western blotting proved that B7-H3 overexpression inhibited apoptosis in colorectal cancer cell lines(P<0.05).B7-H3 overexpression improved Jak2 and STAT3phosphorylation and,in turn,increased the expression of the downstream anti-apoptotic proteins B-cell CLL/lymphoma 2(Bcl-2)and Bcl-xl,based on western blotting(P<0.05).After treating B7-H3 overexpressing cells with the Jak2-specific inhibitor AG490,the phosphorylation of Jak2 and STAT3,and the expression of Bcl-2 and Bcl-xl,decreased accordingly(P<0.05).This finding suggested that the Jak2-STAT3 pathway is involved in the mechanism mediating the anti-apoptotic ability of B7-H3.CONCLUSION:The overexpression of B7-H3 induces resistance to apoptosis in colorectal cancer cell lines by upregulating the Jak2-STAT3 signaling pathway,potentially providing new approaches to the treatment of colorectal cancer.展开更多
Due to rapid urbanization and industrialization, many soils for crop production are contaminated by cadmium(Cd), a heavy metal highly toxic to many organisms. Cereal crops such as rice, wheat, maize, and barley are th...Due to rapid urbanization and industrialization, many soils for crop production are contaminated by cadmium(Cd), a heavy metal highly toxic to many organisms. Cereal crops such as rice, wheat, maize, and barley are the primary dietary source of Cd for humans, and reducing Cd transfer from soil to their grains is therefore an important issue for food safety. During the last decade, great progress has been made in elucidating the molecular mechanisms of Cd transport, particularly in rice. Inter-and intraspecific variations in Cd accumulation have been observed in cereal crops. Transporters for Cd have been identified in rice and other cereal crops using genotypic differences in Cd accumulation and mutant approaches. These transporters belong to different transporter families and are involved in the uptake, vacuolar sequestration, root-to-shoot translocation, and distribution of Cd. Attempts have been made to reduce Cd accumulation in grains by manipulating these transporters through overexpression or knockout of the transporter genes, as well as through marker-assisted selection breeding based on genotypic differences in Cd accumulation in the grains. In this review, we describe recent progress on molecular mechanisms of Cd accumulation in cereal crops and compare different molecular strategies for minimizing Cd accumulation in grains.展开更多
AIM:To study the risk factors for liver metastasis and the prognosis in patients with human epidermal growth factor receptor 2(HER2) over-expressing gastric cancer(GC).METHODS:A total of 84 GC patients recruited from ...AIM:To study the risk factors for liver metastasis and the prognosis in patients with human epidermal growth factor receptor 2(HER2) over-expressing gastric cancer(GC).METHODS:A total of 84 GC patients recruited from the General Hospital of the People's Liberation Army(PLA) between 2003 and 2010 were randomly enrolled in this study.HER2 expression was detected by immunohistochemistry in 84 GC patients with liver metastases.The study group consisted of 66 men and 18 women,with an average age of 54 years(range:19-74 years).Liver metastasis was diagnosed by magnetic resonance imaging or computed tomography.Patients were followed-up and predictive factors of liver metastasis were evaluated.RESULTS:The median follow-up period was 47 mo(range:6-85 mo).The characteristics of 35(25.7%) patients with HER2 over-expression of liver metastatic GC are presented.HER2 over-expression was detected in 23 out of 49(46.9%) patients with intestinal GC,and 9 out of 35(25.7%) patients with diffuse GC.29 out of 59(49.2%) patients aged < 60 years were HER2positive,while 8 out of 25(32%) patients aged ≥ 60 were HER2-positive;a significant difference(P < 0.05).Univariate analysis(log-rank test) showed that HER2 over-expression,sex,Lauren classification,differentiation and disease-free interval were correlated with poor survival(P < 0.05).Survival analysis with a survival curve showed that HER2 over-expression was significantly relevant,with a reduced survival time in GC patients with liver metastases(P < 0.01).2-year survival was not associated with the patient's age.A diseasefree survival longer than 12 mo has a significant association with extended overall survival(OS) in GC patients with liver metastases.The median survival time after the diagnosis of liver metastases was 18 mo [95% confidence interval(CI):9.07-26.94] among HER2 positive GC patients with liver metastases.In comparison,for 49(69.4%) out of 84 HER2 negative patients with liver metastatic GC,the median survival time was 47 mo(95% CI:19.37-74.63).In patients with HER2 positive liver metastatic GC,the median OS was significantly shorter than in HER2 negative patients(median,20.32 mo;95% CI:16.51-24.13 vs median,50.14 mo;95% CI:37.83-62.45;P < 0.01).CONCLUSION:HER2 over-expressing GC patients with liver metastases have a poor prognosis.Overall survival was significantly lower in HER2 positive patients.HER2overexpression is correlated with a lower survival rate.展开更多
microRNAs (miRNAs) play an important regulatory role in the self-renewal and differentiation of stem cells. In this study, we examined the effects of miRNA-124 (miR-124) overexpression in bone marrow-derived mesen...microRNAs (miRNAs) play an important regulatory role in the self-renewal and differentiation of stem cells. In this study, we examined the effects of miRNA-124 (miR-124) overexpression in bone marrow-derived mesenchymal stem cells. In particular, we focused on the effect of overexpression on the differentiation of bone marrow-derived mesenchymal stem cells into neurons. First, we used GeneChip technology to analyze the expression of miRNAs in bone marrow-derived mesen- chymal stem cells, neural stem cells and neurons, miR-124 expression was substantially reduced in bone marrow-derived mesenchymal stem cells compared with the other cell types. We con- structed a lentiviral vector overexpressing miR-124 and transfected it into bone marrow-derived mesenchymal stem cells. Intracellular expression levels of the neuronal early markers [3-III tu- bulin and microtubule-associated protein-2 were significantly increased, and apoptosis induced by oxygen and glucose deprivation was reduced in transfected cells. After miR-124-transfected bone marrow-derived mesenchymal stem cells were transplanted into the injured rat spinal cord, a large number of cells positive for the neuronal marker neurofilament-200 were observed in the transplanted region. The Basso-Beattie-Bresnahan locomotion scores showed that the motor function of the hind limb of rats with spinal cord injury was substantially improved. These re- sults suggest that miR-124 plays an important role in the differentiation of bone marrow-derived mesenchymal stem cells into neurons. Our findings should facilitate the development of novel strategies for enhancing the therapeutic efficacy of bone marrow-derived mesenchymal stem cell transplantation for spinal cord injury.展开更多
AIM:To investigate the mechanisms of the biological roles of Dickkopf-3(Dkk-3) in cell invasion,survival and apoptosis in colon cancer cells.METHODS:Three human colon cancer cell lines,i.e.,HT-29,LoVo and SW480,were u...AIM:To investigate the mechanisms of the biological roles of Dickkopf-3(Dkk-3) in cell invasion,survival and apoptosis in colon cancer cells.METHODS:Three human colon cancer cell lines,i.e.,HT-29,LoVo and SW480,were used.Overexpression of Dkk-3 induced by pEGFP-N1-Dkk-3-GFP plasmid in LoVo cells was performed using Lipofectamine 2000 reagent.Reverse transcription polymerase chain reaction and Western blotting were performed to determine the mRNA and protein expression levels of Dkk-3,respectively.Cell proliferation assay,cell cycle analysis,hoechst 33258 assay and Matrigel invasion assay were performed on Dkk-3 overexpressing transfectants.RESULTS:The mRNA and protein expressions of Dkk-3 in HT-29(mRNA:0.06 ± 0.02,protein:0.06 ± 0.01) and LoVo(mRNA:0.07 ± 0.02,protein:0.07 ± 0.02) cells were significantly lower than that in SW480 cells(mRNA:0.92 ± 0.04,protein:0.69 ± 0.13;all P < 0.05),and the greatest levels of invasiveness wasin LoVo cells.Dkk-3 overexpression inhibited the proliferation and invasion of LoVo cells and induced cell cycle arrest at G0/G1 phase and subsequent apoptosis,as indicated by increased chromatin condensation and fragments,upregulated Bax and cytochrome c protein,downregulated survivin and Bcl-2 protein,and the activation of caspase-3 and caspase-9.Furthermore,Dkk-3 overexpression reduced the accumulation of cytosolic fraction of β-catenin.CONCLUSION:Dkk-3 overexpression induced apoptosis in human colon cancer possibly through the mitochondrial pathway.Dkk-3 may be involved in the Wnt/β-catenin signaling pathways in colon cancer.展开更多
文摘Objective To establish stable prostate cancer bone metastasis cell line overexpressing microRAN-145 (miR-145)for the study of the mechanism of miR-145 in bone metastasis.Methods pMSCV-miR-145 plasmids and retroviruses of pMSCV-vector
文摘By PCR method, apo phycoerythrocyanin α subunit gene (pecA) of Mastigocladus laminosus (M. laminosus) was amplified from its genomic DNA, and then cloned in pBluescript. The pecA gene was subcloned into the expression vector pGEMD, and then transformed into E.coli BL21 (DE3). After induction, a new protein of molecular weight 19×10 3 existing in inclusion body was overexpressed. The expressed product was confirmed to be apo phycoerythrocyanin α subunit by Dot ELISA.
基金Supported by the Project of Sichuan Science and Technology Department(2019YJ0673)National Modern Agriculture Industry System/Sichuan Live Pig Innovation Team(SCSZTD-3-007)。
文摘Carotenoids act as precursors of vitamin A,antioxidants,enhancers of immunity,and are thus widely used in food and pharmaceutical industry.Microbial fermentation is one of the most important solutions for production of natural carotenoids.Rhodobacter sphaeroides is one of most promising bacteria employed for large scale production of carotenoids.In the present study,crtA located in the carotenoids biosynthesis pathway in R.sphaeroides was amplified by PCR.The overexpression vector pRKcrtA was constructed and subsequently transferred into R.sphaeroides,producing the genetically engineered strain R.sphaeroides 2.4.1/pRKcrtA overexpressing crtA.The carotenoid production from the genetically engineered strain was significantly increased.Fermentation procedure was optimized for further enhanced carotenoids production.
基金National Natural Science Foundation of China(31860071)Ministry of Education New Agricultural Research and Reform Practice Program(2020114)+4 种基金Surface Program of Inner Mongolia Natural Science Foundation(2021MS03008)Inner Mongolia Autonomous Region Grassland Talent Innovation Team-Rolling Support Program for Castor Molecular Breeding Research Innovation Talent Teams(2022)2023 Inner Mongolia Autonomous Region Science and Technology Department Establishes the Project of Key Laboratory Construction of Castor Breeding and Comprehensive Utilization in Inner Mongolia Autonomous RegionInner Mongolia University for Nationalities 2022 Basic Research Operating Expenses of Colleges and Universities directly under the Autonomous Region Project(237)Open Fund Project of Castor Industry Collaborative Innovation Center of Inner Mongolia Autonomous Region(MDK2021011,MDK2022014).
文摘Castor is one of the top 10 oil crops in the world and has extremely valuable uses.Castor inflorescences directly affect yield,so the study of inflorescence development is very important in increasing castor yield.Our previous studies have shown that the PIP5K gene family(PIP5Ks)is associated with inflorescence development.In this study,to determine the function of each PIP5K gene in castor,a female Lm-type castor line,aLmAB2,was used to determine the relative expression levels of the PIP5Ks in castor inflorescences.Six PIP5K genes were heterologously overexpressed in Arabidopsis thaliana,the relative expression of each gene and the effect on plants was determined in A.thaliana,and the relationships among the PIP5Ks in castor were inferred.The expression levels of the PIP5Ks in the female Lm-type castor line aLmAB2 were analyzed.The relative expression levels of the PIP5K9 and PIP5K11 genes were high(p<0.05)in isofemale inflorescences,and those of PIP5K1,PIP5K2,PIP5K6,and PIP5K8 were high(p<0.05)in female inflorescences but low(p<0.05)in bisexual inflorescences.The PIP5Ks were heterologously overexpressed in A.thaliana,and T3-generation plants with stable genetic resistance,i.e.,AT-PIP5K^(+)plants(AT-PIP5K1^(+),AT-PIP5K2^(+),AT-PIP5K6^(+),AT-PIP5K8^(+),AT-PIP5K9^(+),and ATPIP5K11^(+) plants),were obtained.Biological tests of the AT-PIP5K+plants showed that the growth of the main stem was significantly delayed in AT-PIP5K+plants compared with Columbia wild-type(WT)A.thaliana plants;the PIP5K1 and PIP5K2 genes promoted lateral stem growth and flower and silique development;and the PIP5K6,PIP5K8,PIP5K9 and PIP5K11 genes inhibited lateral stem growth and flower and silique development.The correlations among PIP5Ks in castor suggest that there may be a synergistic relationship among PIP5K1,PIP5K2,and PIP5K6 in castor inflorescences,and PIP5K8,PIP5K9,and PIP5K11 are complementary to the other three genes.
基金supported by the National Natural Science Foundation of China,Nos.32271043(to ZW)and 82171047(to YM)the both Science and Technology Major Project of Shanghai,No.2018SHZDZX01 and ZJLabShanghai Center for Brain Science and Brain-Inspired Technology(to ZW)。
文摘Downregulation of the inwardly rectifying potassium channel Kir4.1 is a key step for inducing retinal Müller cell activation and interaction with other glial cells,which is involved in retinal ganglion cell apoptosis in glaucoma.Modulation of Kir4.1 expression in Müller cells may therefore be a potential strategy for attenuating retinal ganglion cell damage in glaucoma.In this study,we identified seven predicted phosphorylation sites in Kir4.1 and constructed lentiviral expression systems expressing Kir4.1 mutated at each site to prevent phosphorylation.Following this,we treated Müller glial cells in vitro and in vivo with the m Glu R I agonist DHPG to induce Kir4.1 or Kir4.1 Tyr^(9)Asp overexpression.We found that both Kir4.1 and Kir4.1 Tyr^(9)Asp overexpression inhibited activation of Müller glial cells.Subsequently,we established a rat model of chronic ocular hypertension by injecting microbeads into the anterior chamber and overexpressed Kir4.1 or Kir4.1 Tyr^(9)Asp in the eye,and observed similar results in Müller cells in vivo as those seen in vitro.Both Kir4.1 and Kir4.1 Tyr^(9)Asp overexpression inhibited Müller cell activation,regulated the balance of Bax/Bcl-2,and reduced the m RNA and protein levels of pro-inflammatory factors,including interleukin-1βand tumor necrosis factor-α.Furthermore,we investigated the regulatory effects of Kir4.1 and Kir4.1 Tyr^(9)Asp overexpression on the release of pro-inflammatory factors in a co-culture system of Müller glial cells and microglia.In this co-culture system,we observed elevated adenosine triphosphate concentrations in activated Müller cells,increased levels of translocator protein(a marker of microglial activation),and elevated interleukin-1βm RNA and protein levels in microglia induced by activated Müller cells.These changes could be reversed by Kir4.1 and Kir4.1 Tyr^(9)Asp overexpression in Müller cells.Kir4.1 overexpression,but not Kir4.1 Tyr^(9)Asp overexpression,reduced the number of proliferative and migratory microglia induced by activated Müller cells.Collectively,these results suggest that the tyrosine residue at position nine in Kir4.1 may serve as a functional modulation site in the retina in an experimental model of glaucoma.Kir4.1 and Kir4.1 Tyr^(9)Asp overexpression attenuated Müller cell activation,reduced ATP/P2X receptor–mediated interactions between glial cells,inhibited microglial activation,and decreased the synthesis and release of pro-inflammatory factors,consequently ameliorating retinal ganglion cell apoptosis in glaucoma.
文摘The published article titled“Truncated Bid Overexpression Induced by Recombinant Adenovirus Cre/LoxP System Suppresses the Tumorigenic Potential of CD133+Ovarian Cancer Stem Cells”has been retracted from Oncology Research,Vol.25,No.4,2017,pp.595–603.
文摘Phytase genephyA2, whose signal peptide encoding sequence and intron sequence had been removed, was modified. The Arg-encoding codons CGG and CAG inphyA2 were mutated into synonymous codon AGA. The modifiedphyA2 was fused behind a-factor signal sequence under the control ofAOX1 promoter in plasmid pPIC9, then introduced into the hostPichia pastoris by electroporation. The results of Southern blotting analysis and Northem blotting analysis demonstrated that thephyA2 gene had integrated into the genome ofP. pastoris and transcribed. The result of SDS-PAGE of the phytase expressed by P.pastoris showed that the modifiedphyA2 had been overexpressed and secreted. The concentration of the phytase expressed by P.pastoris with modifiedphyA2 exceeded 15 000 U/mL, which had a 3 000-fold increase over that of originAspergillus niger 963 and was 37 times higher than that of recombinantP. pastoris with non-modifiedphyA2.
基金This study was financially supported by the National Key Research and Development Program of China(2022YFC2804100,2021YFF0502400,2022YFC2804300)National Natural Science Foundation of China(82073713,22137006,82104033,82173730,81903499,32070070,82160669)Innovative research team of highlevel local universities in Shanghai(SHSMU-ZDCX20212702,China).We thank Dr.Juncheng Su from Shanghai Jiao-Tong University School of Medicine(Shanghai,China)for providing the LoVo and COLO 320DM cell lines.
文摘Modulating Tankyrases(TNKS),interactions with USP25 to promote TNKS degradation,rather than inhibiting their enzymatic activities,is emerging as an alternative/specific approach to inhibit the Wnt/β-catenin pathway.Here,we identified UAT-B,a novel neoantimycin analog isolated from Streptomyces conglobatus,as a small-molecule inhibitor of TNKS-USP25 protein-protein interaction(PPI)to overcome multi-drug resistance in colorectal cancer(CRC).The disruption of TNKS-USP25 complex formation by UAT-B led to a significant decrease in TNKS levels,triggering cell apoptosis through modulation of the Wnt/β-catenin pathway.Importantly,UAT-B successfully inhibited the CRC cells growth that harbored high TNKS levels,as demonstrated in various in vitro and in vivo studies utilizing cell line-based and patient-derived xenografts,as well as APC^(min/+)spontaneous CRC models.Collectively,these findings suggest that targeting the TNKS-USP25 PPI using a small-molecule inhibitor represents a compelling therapeutic strategy for CRC treatment,and UAT-B emerges as a promising candidate for further preclinical and clinical investigations.
文摘Correction to:Neurosci.Bull.December,2016,32(6):577–584.https://doi.org/10.1007/s12264-016-0068-z In this article,in Fig 5A,the picture of the Vector+Nogo-66 group was incorrect and should have appeared as shown below.
文摘The published article titled“Overexpression of miR-1283 Inhibits Cell Proliferation and Invasion of Glioma Cells by Targeting ATF4”has been retracted from Oncology Research,Vol.27,No.3,2019,pp.325–334.
基金funded by Biological Breeding-National Science and Technology Major Project(2022ZD04008)Major Science and Technology Project of Hubei Province(2023BBA004)+1 种基金Jiujiang Municipal Key Research and Development Program(2025_001556)the China Agriculture Research System under the Ministry of Agriculture and Rural Affairs and the Chinese Academy of Agricultural Sciences,as well as the Science and Technology Innovation Project of the Chinese Academy of Agricultural Sciences(CAAS-ASTIP-2021-OCRI)。
文摘Drought and salt stresses are major abiotic factors that severely affect the growth,development,and yield formation of Brassica napus.Human derived FTO gene(Fat mass and obesity-associated),is a member of the Alk B family,encoding a m RNA demethylase that is dependent onα-ketoglutarate.Although previous studies have demonstrated that exogenous overexpression of FTO gene can increase plant biomass,its impact on plant stress resistance is still unclear.In this study,we cloned the FTO gene and conducted an analysis of its biological functions for drought and salt resistance for Brassicaceae plants.By overexpressing the FTO gene in Arabidopsis thaliana,the inhibitory effect of salt and drought stress on the root length growth of transgenic lines was significantly lower than that of the control.Moreover,the overexpression of FTO markedly enhanced the tolerance of Arabidopsis to drought and salt stress.It also led to a decrease in malondialdehyde(MDA)content,an increase in proline content,and a boost in superoxide dismutase(SOD)activity.Meanwhile,when the FTO gene was heterologously expressed in B.napus,the transgenic plants were less affected by stress.In comparison to control plants,they exhibited significantly lower MDA levels and markedly higher proline content and SOD activity.Furthermore,staining results with Trypan blue and nitroblue tetrazolium(NBT)staining indicate that the FTO gene can alleviate the damage to plants under stress and inhibit the accumulation of O_(2)^(-).Comprehensively,the results indicate that overexpression of the FTO gene can improve the drought and salt tolerance in transgenic plants,providing valuable references for further exploring the FTO-mediated stress resistance mechanisms.
基金supported by the National Key R&D Program of China(Grant no.2022YFC2807502)Qingdao Marine Science and Technology Center(Grant no.2022QNLM030003-1)Taishan Scholar Distinguished Expert Program in Shandong Province(Grant no.tstp20240504).
文摘A polyketide synthase-nonribosomal peptide synthetase gene cluster twn in Talaromyces sp.HDN1820200 was activated by overexpression of the pathway-specific transcriptional factor TwnD.Large-scale fermentation and chemical investigation of the mutant strain HDN1820200/TwnD led to the discovery of one new polyketide-amino acid conjugate,bipolamide C and one new polyketide compound,variotin A.The structures of the new compounds were determined by nuclear magnetic resonance(NMR)analysis,high-resolution electrospray ionization mass spectrometry,feeding experiments,NMR calculation and DP4^(+)analysis.This study revealed that the overexpression of the pathway-specific transcriptional factor represents a promising approach for the discovery of new natural products in fungi within specialized habitat.
文摘A 1 539 by squalene synthase (AaSQS) cDNA was cloned from a high-yield Artemisia annua L. strain 001 by reverse transcription-polymerise chain reaction (RT-PCR). The amino acid sequence of AaSQS is 70%, 77%, 44% and 39%a identical to that of squalene synthases from Arabidopsis thaliana, tobacco, human and yeast, respectively. The AaSQS genomic DNA has a complex organization containing 14 exons and 13 introns. Full-length or C-terminal truncated cDNA was subcloned into prokaryotic expression vector pET30a and the constructed plasmid was introduced to Escherichia coli strain BL21 (DE3) for induced overexpression. No squalene synthase protein with expected molecular mass was observed in E. cola containing the putative full-length squalene synthase cDNA, however, overexpression in E. coli was achieved by truncating 30 amino acids of hydrophobic region at the carboxy terminus.
基金This work was supported by the Shandong Provincial Education Department Foundation (No. J05K04).
文摘Methyl jasmonate (MeJA) is a plant-signaling molecule that regulates plant morphogenesis and expression of plant defense genes. To determine the role of the endogenous MeJA levels in the development of plants, transgenic soybean [Glycine max (L.) Merrill] plants harboring NTR1 gene encoding for jasmonic acid carboxyl methyltransferase (JMT) were produced. The activation of NTR1 gene expression resulted in the production of MeJA. Overexpression of the NTR1 cDNA under the regulation of cauliflower mosaic virus (CaMV) 35S promoter in the transgenic soybean plants was confirmed using Northern blot analysis. The significant differences in leaf and root growth patterns were observed between the transgenic plants and the wild-type plants. The leaves of the transgenic plants were slightly elongated in length but dramatically narrowed in width compared with the nontrans-formed wild-type plants. In addition, elongation of primary root was inhibited in the overexpressed transgenic soybean plantlets, whereas the development of lateral root was stimulated relative to the nontransformed plants. The leaves of the transgenic plants showed 2-2.5-fold higher levels of MeJA than the control plants. These results indicated that the increased endogenous levels of MeJA is involved in regulation of morphogenesis in soybean plants.
基金supported by grants from the National Basic Research Program of China-the 973 Program(2012CB1247012013CB127306)+2 种基金the Talent Project of guangdong collegesthe Natural Science Foundation of Guangdong Province of China(S2012020011048)the Research Fund for the Doctoral Program of Higher Education
文摘Background:Fatty acid(FA) composition is the most important parameter affecting the flavor and nutritional value of the meat.The final and the only committed step in the biosynthesis of triglycerides is catalyzed by diacylglycerol acyltransferase 2(DGAT2).The role of DGAT2 in lipid accumulation has been demonstrated in adipocytes,However,little is known about the effect of DGAT2 on the FA composition of these cells.Methods:To investigate the role of DGAT2 in regulating lipid accumulation,FA composition and the expression of adipogenic genes,we cloned the open reading frame of the porcine DGAT2 gene and established 3T3-L1 cells that overexpressed DGAT2.Cells were then cultured in differentiation medium(DM) without FA,with a mixture of FAs(FA-DM),or containing a ^(13)C stable isotope-labeled FA mixture(IFA-DM).The FA composition of adipocytes was analyzed by gas chromatography-mass spectrometry and gas chromatography-isotope ratio mass spectrometry.Quantitative PCR and western blotting were employed to detect expression of adipogenic genes in 3T3-L1 adipocytes cultured with FA-DM for 12 d.Results:The triacylglyceride(TAG) content was significantly higher in 3T3-L1 adipocytes overexpressing DGAT2 than in control cells.When cultured in DM or FA-DM for 12 d,cells overexpressing DGAT2 showed a higher proportion of unsaturated FAs(C16:1 and C18:1).However,when cells overexpressing DGAT2 were cultured with FA-DM for30 min,the FA composition was almost identical to that of controls.Further,the proportion of stable isotope-labeled FAs were similar in 3T3-L1 adipocytes overexpressing DGAT2 and control cells cultured in IFA-DM for 12 d.These results collectively indicate that the higher proportion of mono-unsaturated FAs,C16:1 and C18:1,may originate from de novo FA synthesis but not from the uptake of specific FAs from the medium.This hypothesis is further supported by evidence that both mRNA and protein expression of genes involved in FA synthesis(ACACA,FASN,SCD1,and A-FABP)were significantly higher in cells overexpressing DGAT2 than in control cells.Conclusions:In conclusion,our study revealed that TAG accumulation,the proportion of MUFAs,and the expression of adipogenic genes were higher in 3T3-L1 cells overexpressing DGAT2 than in control cells.
基金Supported by Project of Natural Science Foundation of Jiangsu Province,No.BK2012542the Project of Hospital Management Center of Wuxi City,No.YGZ1108
文摘AIM:To investigate the role of the overexpression of B7-H3 in apoptosis in colorectal cancer cell lines and the underlying molecular mechanisms.METHODS:SW620 cells that highly overexpressed B7-H3(SW620-B7-H3-EGFP)and HCT8 cells stably transfected with B7-H3 sh RNA(HCT8-sh B7-H3)were previously constructed in our laboratory.Cells transfected with p IRES2-EGFP were used as negative controls(SW620-NC and HCT8-NC).Real-time PCR and western blotting analysis were used to detect the m RNA and protein expressions of the apoptosis regulator proteins Bcl-2,Bcl-xl and Bax.A cell proliferation assay was used to evaluate the survival rate and drug sensitivity of the cells.The effect of drug resistance was detected by a cell cycle assay.Active caspase-3western blotting was used to reflect the anti-apoptotic ability of cells.Western blotting was also performed to determine the expression of proteins associated with the Jak2-STAT3 signaling pathway and the apoptosis regulator proteins after the treatment with AG490,a Jak2 specific inhibitor,in B7-H3 overexpressing cells.The data were analyzed by Graph Pad Prism 6 using a non-paired t-test.RESULTS:Whether by overexpression in SW620cells or downregulation in HCT8,B7-H3 significantly affected the expression of anti-and pro-apoptotic proteins,at both the transcriptional and translational levels,compared with the negative control(P<0.05).A cell proliferation assay revealed that B7-H3overexpression increased the drug resistance of cells and resulted in a higher survival rate(P<0.05).In addition,the results of cell cycle and active caspase-3western blotting proved that B7-H3 overexpression inhibited apoptosis in colorectal cancer cell lines(P<0.05).B7-H3 overexpression improved Jak2 and STAT3phosphorylation and,in turn,increased the expression of the downstream anti-apoptotic proteins B-cell CLL/lymphoma 2(Bcl-2)and Bcl-xl,based on western blotting(P<0.05).After treating B7-H3 overexpressing cells with the Jak2-specific inhibitor AG490,the phosphorylation of Jak2 and STAT3,and the expression of Bcl-2 and Bcl-xl,decreased accordingly(P<0.05).This finding suggested that the Jak2-STAT3 pathway is involved in the mechanism mediating the anti-apoptotic ability of B7-H3.CONCLUSION:The overexpression of B7-H3 induces resistance to apoptosis in colorectal cancer cell lines by upregulating the Jak2-STAT3 signaling pathway,potentially providing new approaches to the treatment of colorectal cancer.
基金supported by the Grant-in-Aid for Specially Promoted Research, Japan (JSPS KAKENHI Grant No. 16H06296 to J. F. Ma.)the grants from the Scientific Research Development Foundation of Zhejiang A&F University for the Talents, China (No. 2019FR002)the Major Special Science and Technology Project of Zhejiang Province, China (No. 2016C02G2101016)。
文摘Due to rapid urbanization and industrialization, many soils for crop production are contaminated by cadmium(Cd), a heavy metal highly toxic to many organisms. Cereal crops such as rice, wheat, maize, and barley are the primary dietary source of Cd for humans, and reducing Cd transfer from soil to their grains is therefore an important issue for food safety. During the last decade, great progress has been made in elucidating the molecular mechanisms of Cd transport, particularly in rice. Inter-and intraspecific variations in Cd accumulation have been observed in cereal crops. Transporters for Cd have been identified in rice and other cereal crops using genotypic differences in Cd accumulation and mutant approaches. These transporters belong to different transporter families and are involved in the uptake, vacuolar sequestration, root-to-shoot translocation, and distribution of Cd. Attempts have been made to reduce Cd accumulation in grains by manipulating these transporters through overexpression or knockout of the transporter genes, as well as through marker-assisted selection breeding based on genotypic differences in Cd accumulation in the grains. In this review, we describe recent progress on molecular mechanisms of Cd accumulation in cereal crops and compare different molecular strategies for minimizing Cd accumulation in grains.
基金Supported by Technology Found Project Fund for the General Hospital of the People's Liberation Army,No.08CXLXB03
文摘AIM:To study the risk factors for liver metastasis and the prognosis in patients with human epidermal growth factor receptor 2(HER2) over-expressing gastric cancer(GC).METHODS:A total of 84 GC patients recruited from the General Hospital of the People's Liberation Army(PLA) between 2003 and 2010 were randomly enrolled in this study.HER2 expression was detected by immunohistochemistry in 84 GC patients with liver metastases.The study group consisted of 66 men and 18 women,with an average age of 54 years(range:19-74 years).Liver metastasis was diagnosed by magnetic resonance imaging or computed tomography.Patients were followed-up and predictive factors of liver metastasis were evaluated.RESULTS:The median follow-up period was 47 mo(range:6-85 mo).The characteristics of 35(25.7%) patients with HER2 over-expression of liver metastatic GC are presented.HER2 over-expression was detected in 23 out of 49(46.9%) patients with intestinal GC,and 9 out of 35(25.7%) patients with diffuse GC.29 out of 59(49.2%) patients aged < 60 years were HER2positive,while 8 out of 25(32%) patients aged ≥ 60 were HER2-positive;a significant difference(P < 0.05).Univariate analysis(log-rank test) showed that HER2 over-expression,sex,Lauren classification,differentiation and disease-free interval were correlated with poor survival(P < 0.05).Survival analysis with a survival curve showed that HER2 over-expression was significantly relevant,with a reduced survival time in GC patients with liver metastases(P < 0.01).2-year survival was not associated with the patient's age.A diseasefree survival longer than 12 mo has a significant association with extended overall survival(OS) in GC patients with liver metastases.The median survival time after the diagnosis of liver metastases was 18 mo [95% confidence interval(CI):9.07-26.94] among HER2 positive GC patients with liver metastases.In comparison,for 49(69.4%) out of 84 HER2 negative patients with liver metastatic GC,the median survival time was 47 mo(95% CI:19.37-74.63).In patients with HER2 positive liver metastatic GC,the median OS was significantly shorter than in HER2 negative patients(median,20.32 mo;95% CI:16.51-24.13 vs median,50.14 mo;95% CI:37.83-62.45;P < 0.01).CONCLUSION:HER2 over-expressing GC patients with liver metastases have a poor prognosis.Overall survival was significantly lower in HER2 positive patients.HER2overexpression is correlated with a lower survival rate.
基金supported by the National Natural Science Foundation of China,No.81070971
文摘microRNAs (miRNAs) play an important regulatory role in the self-renewal and differentiation of stem cells. In this study, we examined the effects of miRNA-124 (miR-124) overexpression in bone marrow-derived mesenchymal stem cells. In particular, we focused on the effect of overexpression on the differentiation of bone marrow-derived mesenchymal stem cells into neurons. First, we used GeneChip technology to analyze the expression of miRNAs in bone marrow-derived mesen- chymal stem cells, neural stem cells and neurons, miR-124 expression was substantially reduced in bone marrow-derived mesenchymal stem cells compared with the other cell types. We con- structed a lentiviral vector overexpressing miR-124 and transfected it into bone marrow-derived mesenchymal stem cells. Intracellular expression levels of the neuronal early markers [3-III tu- bulin and microtubule-associated protein-2 were significantly increased, and apoptosis induced by oxygen and glucose deprivation was reduced in transfected cells. After miR-124-transfected bone marrow-derived mesenchymal stem cells were transplanted into the injured rat spinal cord, a large number of cells positive for the neuronal marker neurofilament-200 were observed in the transplanted region. The Basso-Beattie-Bresnahan locomotion scores showed that the motor function of the hind limb of rats with spinal cord injury was substantially improved. These re- sults suggest that miR-124 plays an important role in the differentiation of bone marrow-derived mesenchymal stem cells into neurons. Our findings should facilitate the development of novel strategies for enhancing the therapeutic efficacy of bone marrow-derived mesenchymal stem cell transplantation for spinal cord injury.
基金Supported by The Fundamental Research Funds for the Central Universities of China,No.20103020101000197
文摘AIM:To investigate the mechanisms of the biological roles of Dickkopf-3(Dkk-3) in cell invasion,survival and apoptosis in colon cancer cells.METHODS:Three human colon cancer cell lines,i.e.,HT-29,LoVo and SW480,were used.Overexpression of Dkk-3 induced by pEGFP-N1-Dkk-3-GFP plasmid in LoVo cells was performed using Lipofectamine 2000 reagent.Reverse transcription polymerase chain reaction and Western blotting were performed to determine the mRNA and protein expression levels of Dkk-3,respectively.Cell proliferation assay,cell cycle analysis,hoechst 33258 assay and Matrigel invasion assay were performed on Dkk-3 overexpressing transfectants.RESULTS:The mRNA and protein expressions of Dkk-3 in HT-29(mRNA:0.06 ± 0.02,protein:0.06 ± 0.01) and LoVo(mRNA:0.07 ± 0.02,protein:0.07 ± 0.02) cells were significantly lower than that in SW480 cells(mRNA:0.92 ± 0.04,protein:0.69 ± 0.13;all P < 0.05),and the greatest levels of invasiveness wasin LoVo cells.Dkk-3 overexpression inhibited the proliferation and invasion of LoVo cells and induced cell cycle arrest at G0/G1 phase and subsequent apoptosis,as indicated by increased chromatin condensation and fragments,upregulated Bax and cytochrome c protein,downregulated survivin and Bcl-2 protein,and the activation of caspase-3 and caspase-9.Furthermore,Dkk-3 overexpression reduced the accumulation of cytosolic fraction of β-catenin.CONCLUSION:Dkk-3 overexpression induced apoptosis in human colon cancer possibly through the mitochondrial pathway.Dkk-3 may be involved in the Wnt/β-catenin signaling pathways in colon cancer.