Neuronal activity,synaptic transmission,and molecular changes in the basolateral amygdala play critical roles in fear memory.Cylindromatosis(CYLD)is a deubiquitinase that negatively regulates the nuclear factor kappa-...Neuronal activity,synaptic transmission,and molecular changes in the basolateral amygdala play critical roles in fear memory.Cylindromatosis(CYLD)is a deubiquitinase that negatively regulates the nuclear factor kappa-B pathway.CYLD is well studied in non-neuronal cells,yet underinvestigated in the brain,where it is highly expressed.Emerging studies have shown involvement of CYLD in the remodeling of glutamatergic synapses,neuroinflammation,fear memory,and anxiety-and autism-like behaviors.However,the precise role of CYLD in glutamatergic neurons is largely unknown.Here,we first proposed involvement of CYLD in cued fear expression.We next constructed transgenic model mice with specific deletion of Cyld from glutamatergic neurons.Our results show that glutamatergic CYLD deficiency exaggerated the expression of cued fear in only male mice.Further,loss of CYLD in glutamatergic neurons resulted in enhanced neuronal activation,impaired excitatory synaptic transmission,and altered levels of glutamate receptors accompanied by over-activation of microglia in the basolateral amygdala of male mice.Altogether,our study suggests a critical role of glutamatergic CYLD in maintaining normal neuronal,synaptic,and microglial activation.This may contribute,at least in part,to cued fear expression.展开更多
Objective Microcystin-leucine-arginine(MC-LR)exposure induces lipid metabolism disorders in the liver.Secreted frizzled-related protein 5(SFRP5)is a natural antagonist of winglesstype MMTV integration site family,memb...Objective Microcystin-leucine-arginine(MC-LR)exposure induces lipid metabolism disorders in the liver.Secreted frizzled-related protein 5(SFRP5)is a natural antagonist of winglesstype MMTV integration site family,member 5A(Wnt5a)and an anti-inflammatory adipocytokine.In this study,we aimed to investigate whether MC-LR can induce lipid metabolism disorders in hepatocytes and whether SFRP5,which has anti-inflammatory effects,can alleviate the effects of hepatic lipid metabolism by inhibiting the Wnt5a/Jun N-terminal kinase(JNK)pathway.Methods We exposed mice to MC-LR in vivo to induce liver lipid metabolism disorders.Subsequently,mouse hepatocytes that overexpressed SFRP5 or did not express SFRP5 were exposed to MC-LR,and the effects of SFRP5 overexpression on inflammation and Wnt5a/JNK activation by MC-LR were observed.Results MC-LR exposure induced liver lipid metabolism disorders in mice and significantly decreased SFRP5 mRNA and protein levels in a concentration-dependent manner.SFRP5 overexpression in AML12cells suppressed MC-LR-induced inflammation.Overexpression of SFRP5 also inhibited Wnt5a and phosphorylation of JNK.Conclusion MC-LR can induce lipid metabolism disorders in mice,and SFRP5 can attenuate lipid metabolism disorders in the mouse liver by inhibiting Wnt5a/JNK signaling.展开更多
Brain-derived neurotrophic factor(BDNF) attracts increasing attention from both research and clinical fields because of its important functions in the central nervous system. An adequate amount of BDNF is critical to ...Brain-derived neurotrophic factor(BDNF) attracts increasing attention from both research and clinical fields because of its important functions in the central nervous system. An adequate amount of BDNF is critical to develop and maintain normal neuronal circuits in the brain. Given that loss of BDNF function has beenreported in the brains of patients with neurodegenerative or psychiatric diseases, understanding basic properties of BDNF and associated intracellular processes is imperative. In this review, we revisit the gene structure, transcription, translation, transport and secretion mechanisms of BDNF. We also introduce implications of BDNF in several brain-related diseases including Alzheimer's disease, Huntington's disease, depression and schizophrenia.展开更多
In the present study, we investigated the dynamic expression of fibroblast growth factor 8 and Sonic Hedgehog signaling pathway related factors in the process of in vitro hippocampal neural stem/progenitor cell differ...In the present study, we investigated the dynamic expression of fibroblast growth factor 8 and Sonic Hedgehog signaling pathway related factors in the process of in vitro hippocampal neural stem/progenitor cell differentiation from embryonic Sprague-Dawley rats or embryonic Kunming species mice, using fluorescent quantitative reverse transcription-PCR and western blot analyses. Results demonstrated that the dynamic expression of fibroblast growth factor 8 was similar to fibroblast growth factor receptor 1 expression but not to other fibroblast growth factor receptors. Enzyme-linked immunosorbent assay demonstrated that fibroblast growth factor 8 and Sonic Hedgehog signaling pathway protein factors were secreted by neural cells into the intercellular niche. Our experimental findings indicate that fibroblast growth factor 8 and Sonic Hedgehog expression may be related to the differentiation of neural stem/progenitor cells.展开更多
Prolactinoma is an estrogen-related tumor and leukemia-related protein 16 (LRP16) is correlated with the progression of estrogen-related tumors, but the regulatory mechanism between LRP16 and prolactinoma remain unc...Prolactinoma is an estrogen-related tumor and leukemia-related protein 16 (LRP16) is correlated with the progression of estrogen-related tumors, but the regulatory mechanism between LRP16 and prolactinoma remain unclear. This study demonstrates a variation in LRP16 with estrogen receptor a (ERa) in prolactinoma models and the up and downregulation effects of LRP16 on prolactin secretion of pituitary adenomas cells (GH3 cells). In our study, 50 male SD rats (30-day-old) were randomly divided into five groups of 10 rats each. After 120 days of treatment,展开更多
The paper was to study construction and expression of rGhrelin (pcDNA3 -Ghrelin) and its effect on growth performance and gastric acid secretion of rats. Ghrelin amplified from gastric mucosa of weaned piglets was c...The paper was to study construction and expression of rGhrelin (pcDNA3 -Ghrelin) and its effect on growth performance and gastric acid secretion of rats. Ghrelin amplified from gastric mucosa of weaned piglets was cloned into the expression vector pcDNA3 to get recombinant plasmid pcDNA3 - Ghrelin. Twelve weaning rats were randomly divided into two groups, six rats each group. The rats in each treatment group were individually injected with 100pg of naked plasmid pcDNA3 -Ghrelin, and the rats in control group were injected with empty plasmid. The weights and feed consumption of rats were measured after injection for 7, 14 and 29 d, respectively. The rats were sacrificed at the end of the experiment, and their stomach was separated and weighed, the pH value of gastric juice was measured as well. The results showed that the average daily gain of rats at 7 and 29 d were significantly higher than that in control group, respectively (P〈0.05), and feed consumption did not have significant chan- ges; the feed meat ratio of rats in the treatment groups was significantly lower than that in control group ( P 〈0.05) ; the gastric relative weight and gastric weight did not change significantly, while the pH value of gastric juice of rats in treatment groups was significantly lower than that in control group (P 〈 0.05). This indicated that after transfected expression of muscle tissue, ghrelin played an important regulatory role in growth and gastric acid secretion of rats.展开更多
To study the effects of free fatty acids on insulin secretion and expression of SUR1 gene in rat pancreatic B cells in vitro, and to explore the molecular mechanisms in lipotoxicity inducing insulin secretion dysfunc...To study the effects of free fatty acids on insulin secretion and expression of SUR1 gene in rat pancreatic B cells in vitro, and to explore the molecular mechanisms in lipotoxicity inducing insulin secretion dysfunction, pancreatic islet cells were isolated and digested from male SD rats. Purified islets were incubated with either 0.25 mmol/L palmitate or 0.125 mmol/L oleate for 48 h in vitro. Then islets were stimulated with either 5.6 mmol/L or 16.7 mmol/L glucose for 1 h. Insulin release was measured by using radioimmunoassay, and the expression of SUR1 gene mRNA was quantified by reserve transcription-polymerase chain reaction (RT-PCR). The islets exposed to both palmitate and oleate for 48 h showed an increased basal and a decreased glucose-indused insulin release as compared with control islets. Palmitate increased basal insulin secretion by 110 % (P<0.01), decreased glucose stimulated insulin secretion by 43 % (P<0.01); while oleate increased basal insulin secretion by 80 % (P<0.01) and decreased glucose stimulated insulin secretion by 32 % (P<0.05). RT-PCR showed that oleate significantly suppressed SUR1 gene expression by 64 % (P<0.01)as compared with the control group, while palmitate group manifested a light decrease of 15 % (P >0.05) of SUR1 gene expression. Our results suggested that chronic exposure to free fatty acids of pancreatic β cells inhibited glucose stimulated insulin secretion. Regulation of SUR1 gene expression may be involved in such effects, which may also be one of the molecular mechanisms in lipotoxocity inducing β cells secretion dysfunction.展开更多
In order to enrich the research about type III secretion system (T3SS) injectisome of Vibrio alginolyticus, vscX gene was cloned from E algianlyticus strain HY9901 for bioinformatics analysis and expression analysis...In order to enrich the research about type III secretion system (T3SS) injectisome of Vibrio alginolyticus, vscX gene was cloned from E algianlyticus strain HY9901 for bioinformatics analysis and expression analysis. Specific primers were designed according to the full-length geanme sequence of V. alginolyticus in GenBank. vscX gene (C, enBank accession number: FR780679) contained a 378 bp open reading frame (ORF), encoding a putative protein of 125 amino acids. The theoretical molecular weight was 14.209 2 kD and theoretical pI was 5.75. By using Signal 4.1 Server and TMHMM Server 2.0, it was predicted that VscX protein had no transmembrane domain or signal peptide. The results of prediction using SoftBerry-Psite software showed that VscX protein contained three casein ki- nase lI phosphorylation sites, one N-myristoylation site and three C-terminal targeting signal sites. Subcellular localization revealed that VscX might be located in cytoplasm with the possibility of 56.5%. According to SMART prediction, VscX had one Pfam ( 1 - 125 aa) domain. Phylogenetic analysis revealed that VscX from V. alginolyticus and VscX from E parahemolyticus were clustered into the same group. Network interaction analysis showed that vscX was adjacent to vseY, vopB and sycN. By real-time fluorescent quantitative PCR technique and 2-△△△ method, the differences in expression levels of VscX mRNA in V. alginolyticus strain HY9901, T3SS deletion strain AvscO and complementary strain C-vscO at different growth stages were analyzed. The results showed that the expression levels of VscX mRNA in V. algianlyticus strain HY9901 and C-vscO were significantly up-regulated at stable growth stage ( P 〈0.01 ) ; the expression levels of VscX mRNA in deletion strain △vscO were significantly up-regulated at late growth stage ( P 〈0.01 ). This study provided the basis for revealing the transport mechanism of T3SS injectisome of E alginolyticus.展开更多
[Objective] The research aimed to study the secreted expression of S-edenosyl-L-methionine synthetase (SAMS) in Pichia pastoris. Method ] The gene coding SAMS, from the genomic DNA of Saccharomyces cerevisiae, was ...[Objective] The research aimed to study the secreted expression of S-edenosyl-L-methionine synthetase (SAMS) in Pichia pastoris. Method ] The gene coding SAMS, from the genomic DNA of Saccharomyces cerevisiae, was amplified by PCR and inserted into the secreted expression vector pPIC9K to get recombinant plasmid. The recombinant plasmid pPIC9K-sarr~ was integrated into Pichia pastoris GSl15 genome by electroporation and induced by methanol. The activity of the recombinant enzyme was measured using high-pedormance liquid chroma- tography (HPLC) by determining the production of S-adenosy-L-methionine (SAM) with the enzyme secreted. [ ResultJ The molecular weight of the expression protein identified by SDS-PAGE was about 50 kD, being larger than the theoretical molecular mass of SAMS, which might be due to the glycosytation in the process of secretion. Methanol-induction as well as preliminary purification could enhance the enzyme activity, espe- cially the latter, after which the specific activity of SAMS was improved to 61.48 U/rng. [Conclusion] SAMS with biological activity was secreted successfully in Pichia pastoris GSl15 for the first time. And it is the start for the genetic engineering strains to open up prospects for industrial production.展开更多
Objective To investigate the value of BT-H3 in expressed prostatic secretions ( EPS) in differential diagnosis of patients with inflammatory elevation of PSA in t - PSA gray zone ( 4 - 10 ng /ml) . Methods One hundred...Objective To investigate the value of BT-H3 in expressed prostatic secretions ( EPS) in differential diagnosis of patients with inflammatory elevation of PSA in t - PSA gray zone ( 4 - 10 ng /ml) . Methods One hundred and sixteen patients from ages of 19 to 80 years ( mean,40 years) were studied. In the group there展开更多
The methanol inducible alcohol oxidase 1 promoter and the Saccharomyces cerevisiae alpha-factor prepro secretion signal were used to drive expression and secretion of a mucin-type fusion protein by Pichia pastoris in ...The methanol inducible alcohol oxidase 1 promoter and the Saccharomyces cerevisiae alpha-factor prepro secretion signal were used to drive expression and secretion of a mucin-type fusion protein by Pichia pastoris in 1 L scale bioreactors. The aim of the study was to understand how varying expression rates influenced the secretion dynamics of the fusion protein in terms of intracellular- and extracellular concentrations. Endoplasmic reticulum (ER) folding stress was assessed by the relative expression of the unfolded protein response controlled KAR2 gene. Three predefined methanol feeding models were applied to control the fusion protein synthesis rate. To track the fusion protein synthesis in a non-invasive manner and to follow its intracellular distribution, its C-terminal was linked to the green fluorescent protein. Under all conditions the fusion protein was found to partially accumulate intracellularly, where the major fraction was an insoluble, fluorescent full-sized protein. The high degree of glycosylation of the insoluble fusion protein indicated a secretory bottle-neck in the Golgi-system. This result was consistent with low ER folding stress as quantified by the relative expression of the KAR2 gene. Reduction of recombinant protein synthesis rate, by using lower feed rates of methanol, enhanced extracellular concentrations from 8 to 18 mg·L–1 and reduced the rate of intracellular accumulation. This clearly demonstrates the importance of tuning the synthesis rate with secretory bottle-necks to maintain secretion.展开更多
Heat shock transcription factors(Hsfs)have important roles during plant growth and development and responses to abiotic stresses.The identification and func-tion of Hsf genes have been thoroughly studied in various he...Heat shock transcription factors(Hsfs)have important roles during plant growth and development and responses to abiotic stresses.The identification and func-tion of Hsf genes have been thoroughly studied in various herbaceous plant species,but not woody species,especially Phoebe bournei,an endangered,unique species in China.In this study,17 members of the Hsf gene family were identi-fied from P.bournei using bioinformatic methods.Phyloge-netic analysis indicated that PbHsf genes were grouped into three subfamilies:A,B,and C.Conserved motifs,three-dimensional structure,and physicochemical properties of the PbHsf proteins were also analyzed.The structure of the PbHsf genes varied in the number of exons and introns.Pre-diction of cis-acting elements in the promoter region indi-cated that PbHsf genes are likely involved in responses to plant hormones and stresses.A collinearity analysis dem-onstrated that expansions of the PbHsf gene family mainly take place via segmental duplication.The expression levels of PbHsf genes varied across different plant tissues.On the basis of the expression profiles of five representative PbHsf genes during heat,cold,salt,and drought stress,PbHsf pro-teins seem to have multiple functions depending on the type of abiotic stress.This systematic,genome-wide investigation of PbHsf genes in P.bournei and their expression patterns provides valuable insights and information for further func-tional dissection of Hsf proteins in this endangered,unique species.展开更多
Vascular etiology is the second most prevalent cause of cognitive impairment globally.Endothelin-1,which is produced and secreted by endothelial cells and astrocytes,is implicated in the pathogenesis of stroke.However...Vascular etiology is the second most prevalent cause of cognitive impairment globally.Endothelin-1,which is produced and secreted by endothelial cells and astrocytes,is implicated in the pathogenesis of stroke.However,the way in which changes in astrocytic endothelin-1 lead to poststroke cognitive deficits following transient middle cerebral artery occlusion is not well understood.Here,using mice in which astrocytic endothelin-1 was overexpressed,we found that the selective overexpression of endothelin-1 by astrocytic cells led to ischemic stroke-related dementia(1 hour of ischemia;7 days,28 days,or 3 months of reperfusion).We also revealed that astrocytic endothelin-1 overexpression contributed to the role of neural stem cell proliferation but impaired neurogenesis in the dentate gyrus of the hippocampus after middle cerebral artery occlusion.Comprehensive proteome profiles and western blot analysis confirmed that levels of glial fibrillary acidic protein and peroxiredoxin 6,which were differentially expressed in the brain,were significantly increased in mice with astrocytic endothelin-1 overexpression in comparison with wild-type mice 28 days after ischemic stroke.Moreover,the levels of the enriched differentially expressed proteins were closely related to lipid metabolism,as indicated by Kyoto Encyclopedia of Genes and Genomes pathway analysis.Liquid chromatography-mass spectrometry nontargeted metabolite profiling of brain tissues showed that astrocytic endothelin-1 overexpression altered lipid metabolism products such as glycerol phosphatidylcholine,sphingomyelin,and phosphatidic acid.Overall,this study demonstrates that astrocytic endothelin-1 overexpression can impair hippocampal neurogenesis and that it is correlated with lipid metabolism in poststroke cognitive dysfunction.展开更多
The antifungal peptides, drosomycin (Drs) and its isoform drosomycin-like C (Drs-lC) from Drosophila melanogaster and Thanatin from Podisus maculiventris, have potent activity with broad spectrum against filamento...The antifungal peptides, drosomycin (Drs) and its isoform drosomycin-like C (Drs-lC) from Drosophila melanogaster and Thanatin from Podisus maculiventris, have potent activity with broad spectrum against filamentous fungi. Secretive expression of these genes in yeasts makes it possible to utilize the supernatants of yeast culture as protective reagents on fruit, vegetable, food and other agricultural products. So the study of effective secretion by yeast expression system is of great importance. Three genes, Drs, Drs-lC, and Thanatin, were cloned into pPICZαA and the recombinant vectors, pPICZαA-Drs, pPICZαA-Drs-lC, and pPICZαA-Thanatin were transformed into Pichia pastoris by the electric transfer method. The recombinant P. pastoris, which was screened by phenotype selection and PCR amplification, was induced to express antifungal peptide by methanol. The expressive products of the three recombinants showed antifungal activity against 5 out of 6 test fungi strains, and the products of Thanatin also had strong activity against the tested bacteria. The three antifungal peptide genes, Drs, Drs-lC, and Thanatin, were constructed into yeast P. pastoris. The expressed peptides were successfully secreted into the culture medium and exhibited potent activities against the test strains.展开更多
Objective This study is to examine the secretion effects of β-galactosidase in Lactococcus lactis.Methods The usp45 and β-galactosidase genes were cloned and inserted into plasmid pMG36e to obtain the recombinant pl...Objective This study is to examine the secretion effects of β-galactosidase in Lactococcus lactis.Methods The usp45 and β-galactosidase genes were cloned and inserted into plasmid pMG36e to obtain the recombinant plasmid pMG36e-usp-lacZ.This recombinant plasmid was transformed into both Escherichia coli DH5α and L.lactis MG1363.The enzyme activity,gene sequencing,SDS-PAGE and hereditary stability were assessed and studied.Results The lacZ gene inserted into plasmids pMG36e-usp-lacZ was 99.37% similar to the GenBank sequence,and SDS-PAGE revealed an evident idio-strap at 116 KDa between L.lactis MG1363/pMG36eusp-lacZ in both supernatant and cell samples.β-Galactosidase activity measured 0.225 U/mL in L.lactis pMG36e-usp-lacZ transformants,and its secretion rate was 10%.The plasmid pMG36e-usp-lacZ appeared more stable in MG1363.Conclusion The authors concluded that these new recombinant bacteria well expressed and secreted β-galactosidase,indicating that the β-galactosidase expression system was successfully constructed,and this might provide a new solution for management of lactose intolerance specifically and promote the use of gene-modified organisms as part of the food-grade plasmid in general.展开更多
AIM: To investigate the functions of promoter hypermethylation of secreted frizzled-related proteins (sFRPs) genes in colorectal tumorigenesis and progression. METHODS: The promoter hypermethylation and expression...AIM: To investigate the functions of promoter hypermethylation of secreted frizzled-related proteins (sFRPs) genes in colorectal tumorigenesis and progression. METHODS: The promoter hypermethylation and expression of sFRP genes in 72 sporadic colorectal carcinomas, 33 adenomas, 18 aberrant crypt foci (ACF) and colorectal cancer cell lines RKO, HCT116 and SW480 were detected by methylation-specific PCR and reverse transcription PCR, respectively. RESULTS: None of the normal colorectal mucosa tissues showed methylated bands of any of four sFRP genes, sFRP1, 2, 4 and 5 were frequently methylated in colorectal carcinoma, adenoma and ACF (sFRP1 〉 85%, sFRP2 〉75%, sFRP5 〉 50%), and the differences between three colorectal tissues were not significant (P 〉 0.05). IVlethylation in colorectal tumors was more frequent than in normal mucosa and adjacent normal mucosa. The mRNA of sFRP1-5 genes was expressed in all normal colorectal mucosa samples. Expression of sFRP1, 2, 4 and 5 and sFRP1, 2 and 5 was downregulated in carcinoma and adenoma, respectively. The downregulation of sFRP2, 4 and 5 was more frequent in carcinoma than in adenoma. Expression of sFRP3 which promoter has no CpG island was downregulated in only a few of colorectal tumor samples (7/105). The downregulation ofsFRP1, 2, 4 and 5 expression was significantly associated with promoter hypermethylation in colorectal tumor. After cells were treated by DAC/TSA combination, the silenced sFRP mRNA expression could be effectively re-expressed in colorectal cancer cell lines. CONCLUSION: Hypermethylation of sFRP genes is a common early event in the evolution of colorectal tumor, occurring frequently in ACF, which is regarded as the earliest lesion of multistage colorectal carcinogenesis. It appears to functionally silence sFRP genes expression. Methylation of sFRP1, 2 and 5 genes might serve as indicators for colorectal tumor.展开更多
BACKGROUND Cyclin-dependent kinase 9(CDK9)expression and autophagy in colorectal cancer(CRC)tissues has not been widely studied.CDK9,a key regulator of transcription,may influence the occurrence and progression of CRC...BACKGROUND Cyclin-dependent kinase 9(CDK9)expression and autophagy in colorectal cancer(CRC)tissues has not been widely studied.CDK9,a key regulator of transcription,may influence the occurrence and progression of CRC.The expression of auto-phagy-related genes BECN1 and drug resistance factor ABCG2 may also play a role in CRC.Under normal physiological conditions,autophagy can inhibit tumorigenesis,but once a tumor forms,autophagy may promote tumor growth.Therefore,understanding the relationship between autophagy and cancer,partic-ularly how autophagy promotes tumor growth after its formation,is a key motivation for this research.AIM To investigate the relationship between CDK9 expression and autophagy in CRC,assess differences in autophagy between left and right colon cancer,and analyze the associations of autophagy-related genes with clinical features and prognosis.METHODS We collected tumor tissues and paracarcinoma tissues from colon cancer patients with liver metastasis to observe the level of autophagy in tissues with high levels of CDK9 and low levels of CDK9.We also collected primary tissue from left and right colon cancer patients with liver metastasis to compare the autophagy levels and the expression of BECN1 and ABCG2 in the tumor and paracarcinoma tissues.RESULTS The incidence of autophagy and the expression of BECN1 and ABCG2 were different in left and right colon cancer,and autophagy might be involved in the occurrence of chemotherapy resistance.Further analysis of the rela-tionship between the expression of autophagy-related genes CDK9,ABCG2,and BECN1 and the clinical features and prognosis of colorectal cancer showed that the high expression of CDK9 indicated a poor prognosis in colorectal cancer.CONCLUSION This study laid the foundation for further research on the combination of CDK9 inhibitors and autophagy inhibitors in the treatment of patients with CRC.展开更多
AIM: To identify the methylation of secreted frizzled-related protein 1 (SFRP1) in gastric cancer and to investigate the aberrant expression of SFRP1 and its correlation with the clinical pathological features of p...AIM: To identify the methylation of secreted frizzled-related protein 1 (SFRP1) in gastric cancer and to investigate the aberrant expression of SFRP1 and its correlation with the clinical pathological features of patients. METHODS: We determined SFRP1 methylation and SFRP1 mRNA expression in 3 gastric cancer cell lines SGC-7901, BGC-823, HGC-27, from 52 primary gastric cancer specimens and matched tumor adjacent tissue specimens by methylation-specific (MSP) PCR and RT-PCR respectively. Fisher's exact test was used to analyze the statistical association between clinical pathological data and aberrant expression of SFRP1. RESULTS: In 3 cancer cell lines, BGC-823 and HGC-27 had methylated SFRP1 and lost SFRP1 mRNA expression. After treatment of BGC-823 and HGC-27 with the demethylating agent, 5-aza-2′-deoxycytidine, SFRP1 was re-expressed. In 52 primary gastric cancer specimens and matched tumor adjacent tissue specimens, hypermethylation of SFRP1 was detected in 23 (44%) and 8 (15%) specimens respectively (x^2= 10.34, P 〈 0.01). Loss of SFRP1 expression was detected in 17(33%) and 6 (12%) specimens respectively (x^2= 6.75, P 〈 0.01). There was a significant correlation between SFRP1 hypermethylation and SFRP1 expression loss. SFRP1 expression was also correlated significantly with tumor stage and lymph node status, but not with patient sex, age and histological type. CONCLUSION: SFRP1 inactivation is a common and early event caused mainly by hypermethylation in gastric cancer. SFRP1 expression loss may be correlated with tumor metastasis in primary gastric cancer.展开更多
AIM:To determine the methylation status and aberrant expression of some secreted frizzled-related protein(SFRP) genes in pancreatic cancer and explore their role in pancreatic carcinogenesis.METHODS:Methylation st...AIM:To determine the methylation status and aberrant expression of some secreted frizzled-related protein(SFRP) genes in pancreatic cancer and explore their role in pancreatic carcinogenesis.METHODS:Methylation status and expression of SFRP genes were detected by methylation-specific PCR(MSPCR) and reverse-transcription PCR(RT-PCR) respectively.RESULTS:The frequencies of methylation for SFRP genes 1,2,4,5 were 70%,48.3%,60% and 76.7% in pancreatic cancer samples,and 21.7%,20%,10% and 36.7% in matched cancer adjacent normal tissue samples,respectively(χ^2 = 28.23,P 〈 0.0001 for SFRP gene 1;χ^2 = 10.71,P = 0.001 for SFRP gene 2;χ^2 = 32.97,P 〈 0.0001 for SFRP gene 4;χ^2 = 19.55,P 〈 0.0001 for SFRP gene 5).Expression loss of SFRP genes 1,2,4 and 5 was found in 65%,40%,55% and 71.7% of 60 pancreatic cancer samples,and 25%,15%,18.3% and 31.7% of matched cancer adjacent normal tissue samples,respectively(χ^2 = 19.39,P 〈 0.0001 for SFRP gene 1;χ^2 = 9.40,P = 0.002 for SFRP gene 2;χ^2 = 17.37,P 〈 0.0001 for SFRP gene 4;χ^2 = 19.22,P 〈 0.0001 for SFRP gene 5).SFRP gene 1 was methylated but not expressed in PC-3 and PANC-1,SFRP gene 2 was methylated but not expressed in PANC-1 and CFPAC-1,SFRP gene 4 was methylated but not expressed in PC-3,and SFRP gene 5was methylated but not expressed in CFPAC-1.CONCLUSION: Hypermethylation and aberrant expression of SFRP genes are common in pancreatic cancer, which may be involved in pancreatic carcinogenesis.展开更多
基金supported by the National Natural Science Foundation of China,Nos.32371065(to CL)and 32170950(to LY)the Natural Science Foundation of the Guangdong Province,No.2023A1515010899(to CL)the Science and Technology Projects in Guangzhou,Nos.2023A4J0578 and 2024A03J0180(to CW)。
文摘Neuronal activity,synaptic transmission,and molecular changes in the basolateral amygdala play critical roles in fear memory.Cylindromatosis(CYLD)is a deubiquitinase that negatively regulates the nuclear factor kappa-B pathway.CYLD is well studied in non-neuronal cells,yet underinvestigated in the brain,where it is highly expressed.Emerging studies have shown involvement of CYLD in the remodeling of glutamatergic synapses,neuroinflammation,fear memory,and anxiety-and autism-like behaviors.However,the precise role of CYLD in glutamatergic neurons is largely unknown.Here,we first proposed involvement of CYLD in cued fear expression.We next constructed transgenic model mice with specific deletion of Cyld from glutamatergic neurons.Our results show that glutamatergic CYLD deficiency exaggerated the expression of cued fear in only male mice.Further,loss of CYLD in glutamatergic neurons resulted in enhanced neuronal activation,impaired excitatory synaptic transmission,and altered levels of glutamate receptors accompanied by over-activation of microglia in the basolateral amygdala of male mice.Altogether,our study suggests a critical role of glutamatergic CYLD in maintaining normal neuronal,synaptic,and microglial activation.This may contribute,at least in part,to cued fear expression.
基金supported by the Natural Science Research Project of colleges and Universities in Anhui Province[2022AH052336]High Level Talent Research Initiation Fund Of Anhui Medical College[2023RC004]。
文摘Objective Microcystin-leucine-arginine(MC-LR)exposure induces lipid metabolism disorders in the liver.Secreted frizzled-related protein 5(SFRP5)is a natural antagonist of winglesstype MMTV integration site family,member 5A(Wnt5a)and an anti-inflammatory adipocytokine.In this study,we aimed to investigate whether MC-LR can induce lipid metabolism disorders in hepatocytes and whether SFRP5,which has anti-inflammatory effects,can alleviate the effects of hepatic lipid metabolism by inhibiting the Wnt5a/Jun N-terminal kinase(JNK)pathway.Methods We exposed mice to MC-LR in vivo to induce liver lipid metabolism disorders.Subsequently,mouse hepatocytes that overexpressed SFRP5 or did not express SFRP5 were exposed to MC-LR,and the effects of SFRP5 overexpression on inflammation and Wnt5a/JNK activation by MC-LR were observed.Results MC-LR exposure induced liver lipid metabolism disorders in mice and significantly decreased SFRP5 mRNA and protein levels in a concentration-dependent manner.SFRP5 overexpression in AML12cells suppressed MC-LR-induced inflammation.Overexpression of SFRP5 also inhibited Wnt5a and phosphorylation of JNK.Conclusion MC-LR can induce lipid metabolism disorders in mice,and SFRP5 can attenuate lipid metabolism disorders in the mouse liver by inhibiting Wnt5a/JNK signaling.
基金Supported by The Health and Labor Sciences Research Grants(Comprehensive Research on Disability,Health,and Welfare H21-kokoro-002)(H.K.)the Core Research for Evolutional Science and Technology Program,CREST,Japan Science and Technology Agency(JST)(T.N.,N.A.and H.K.)+3 种基金the Naito Foundation(N.A)the Takeda Science Foundation(T.N.)a grant from Grant-in-Aid for Scientific Research(B),(JSPS KAKENHI)(T.N.),No.24300139Grant-in-Aid for Challenging Exploratory Research(JSPS KAKENHI)(T.N.)from the Ministry of Education,Culture,Sports,Science,and Technology of Japan,No.25640019
文摘Brain-derived neurotrophic factor(BDNF) attracts increasing attention from both research and clinical fields because of its important functions in the central nervous system. An adequate amount of BDNF is critical to develop and maintain normal neuronal circuits in the brain. Given that loss of BDNF function has beenreported in the brains of patients with neurodegenerative or psychiatric diseases, understanding basic properties of BDNF and associated intracellular processes is imperative. In this review, we revisit the gene structure, transcription, translation, transport and secretion mechanisms of BDNF. We also introduce implications of BDNF in several brain-related diseases including Alzheimer's disease, Huntington's disease, depression and schizophrenia.
基金supported by the National Natural Science Foundation of China,No.81070614the Key Project of the Natural Science Foundation of Hubei Province of China,No.2008CDA044the Natural Science Foundation of Hubei University of Medicine,No.2011QDZR-2
文摘In the present study, we investigated the dynamic expression of fibroblast growth factor 8 and Sonic Hedgehog signaling pathway related factors in the process of in vitro hippocampal neural stem/progenitor cell differentiation from embryonic Sprague-Dawley rats or embryonic Kunming species mice, using fluorescent quantitative reverse transcription-PCR and western blot analyses. Results demonstrated that the dynamic expression of fibroblast growth factor 8 was similar to fibroblast growth factor receptor 1 expression but not to other fibroblast growth factor receptors. Enzyme-linked immunosorbent assay demonstrated that fibroblast growth factor 8 and Sonic Hedgehog signaling pathway protein factors were secreted by neural cells into the intercellular niche. Our experimental findings indicate that fibroblast growth factor 8 and Sonic Hedgehog expression may be related to the differentiation of neural stem/progenitor cells.
基金financially supported by the National Natural Science Foundation of China and Hainan Province.[NSFC,Grant Nos.81570705 and 81270866NSFH,Grant No.20168353]
文摘Prolactinoma is an estrogen-related tumor and leukemia-related protein 16 (LRP16) is correlated with the progression of estrogen-related tumors, but the regulatory mechanism between LRP16 and prolactinoma remain unclear. This study demonstrates a variation in LRP16 with estrogen receptor a (ERa) in prolactinoma models and the up and downregulation effects of LRP16 on prolactin secretion of pituitary adenomas cells (GH3 cells). In our study, 50 male SD rats (30-day-old) were randomly divided into five groups of 10 rats each. After 120 days of treatment,
基金Supported by National Natural Science Foundation for Young Scholar(31302054)Natural Science Foundation of Jiangsu Province(BK20131086)Natural Science Foundation of Tianjin City(13JCYBJC25300)
文摘The paper was to study construction and expression of rGhrelin (pcDNA3 -Ghrelin) and its effect on growth performance and gastric acid secretion of rats. Ghrelin amplified from gastric mucosa of weaned piglets was cloned into the expression vector pcDNA3 to get recombinant plasmid pcDNA3 - Ghrelin. Twelve weaning rats were randomly divided into two groups, six rats each group. The rats in each treatment group were individually injected with 100pg of naked plasmid pcDNA3 -Ghrelin, and the rats in control group were injected with empty plasmid. The weights and feed consumption of rats were measured after injection for 7, 14 and 29 d, respectively. The rats were sacrificed at the end of the experiment, and their stomach was separated and weighed, the pH value of gastric juice was measured as well. The results showed that the average daily gain of rats at 7 and 29 d were significantly higher than that in control group, respectively (P〈0.05), and feed consumption did not have significant chan- ges; the feed meat ratio of rats in the treatment groups was significantly lower than that in control group ( P 〈0.05) ; the gastric relative weight and gastric weight did not change significantly, while the pH value of gastric juice of rats in treatment groups was significantly lower than that in control group (P 〈 0.05). This indicated that after transfected expression of muscle tissue, ghrelin played an important regulatory role in growth and gastric acid secretion of rats.
基金ThisprojectwassupportedbyagrantfromtheScientificResearchFoundationfortheReturnedOverseasChineseScholarsbytheStateEducationMinistryofChina (No .2 0 0 2 2 4 7) ,theNaturalScienceFoundationofHubeiofChina (No .2 0 0 2AB136 )andWuhanFoundationofScienceandTech
文摘To study the effects of free fatty acids on insulin secretion and expression of SUR1 gene in rat pancreatic B cells in vitro, and to explore the molecular mechanisms in lipotoxicity inducing insulin secretion dysfunction, pancreatic islet cells were isolated and digested from male SD rats. Purified islets were incubated with either 0.25 mmol/L palmitate or 0.125 mmol/L oleate for 48 h in vitro. Then islets were stimulated with either 5.6 mmol/L or 16.7 mmol/L glucose for 1 h. Insulin release was measured by using radioimmunoassay, and the expression of SUR1 gene mRNA was quantified by reserve transcription-polymerase chain reaction (RT-PCR). The islets exposed to both palmitate and oleate for 48 h showed an increased basal and a decreased glucose-indused insulin release as compared with control islets. Palmitate increased basal insulin secretion by 110 % (P<0.01), decreased glucose stimulated insulin secretion by 43 % (P<0.01); while oleate increased basal insulin secretion by 80 % (P<0.01) and decreased glucose stimulated insulin secretion by 32 % (P<0.05). RT-PCR showed that oleate significantly suppressed SUR1 gene expression by 64 % (P<0.01)as compared with the control group, while palmitate group manifested a light decrease of 15 % (P >0.05) of SUR1 gene expression. Our results suggested that chronic exposure to free fatty acids of pancreatic β cells inhibited glucose stimulated insulin secretion. Regulation of SUR1 gene expression may be involved in such effects, which may also be one of the molecular mechanisms in lipotoxocity inducing β cells secretion dysfunction.
基金Supported by National Natural Science Foundation of China(31402344,31572656)Major Program of Natural Science Foundation of Guangdong Province(2015A030308020)
文摘In order to enrich the research about type III secretion system (T3SS) injectisome of Vibrio alginolyticus, vscX gene was cloned from E algianlyticus strain HY9901 for bioinformatics analysis and expression analysis. Specific primers were designed according to the full-length geanme sequence of V. alginolyticus in GenBank. vscX gene (C, enBank accession number: FR780679) contained a 378 bp open reading frame (ORF), encoding a putative protein of 125 amino acids. The theoretical molecular weight was 14.209 2 kD and theoretical pI was 5.75. By using Signal 4.1 Server and TMHMM Server 2.0, it was predicted that VscX protein had no transmembrane domain or signal peptide. The results of prediction using SoftBerry-Psite software showed that VscX protein contained three casein ki- nase lI phosphorylation sites, one N-myristoylation site and three C-terminal targeting signal sites. Subcellular localization revealed that VscX might be located in cytoplasm with the possibility of 56.5%. According to SMART prediction, VscX had one Pfam ( 1 - 125 aa) domain. Phylogenetic analysis revealed that VscX from V. alginolyticus and VscX from E parahemolyticus were clustered into the same group. Network interaction analysis showed that vscX was adjacent to vseY, vopB and sycN. By real-time fluorescent quantitative PCR technique and 2-△△△ method, the differences in expression levels of VscX mRNA in V. alginolyticus strain HY9901, T3SS deletion strain AvscO and complementary strain C-vscO at different growth stages were analyzed. The results showed that the expression levels of VscX mRNA in V. algianlyticus strain HY9901 and C-vscO were significantly up-regulated at stable growth stage ( P 〈0.01 ) ; the expression levels of VscX mRNA in deletion strain △vscO were significantly up-regulated at late growth stage ( P 〈0.01 ). This study provided the basis for revealing the transport mechanism of T3SS injectisome of E alginolyticus.
文摘[Objective] The research aimed to study the secreted expression of S-edenosyl-L-methionine synthetase (SAMS) in Pichia pastoris. Method ] The gene coding SAMS, from the genomic DNA of Saccharomyces cerevisiae, was amplified by PCR and inserted into the secreted expression vector pPIC9K to get recombinant plasmid. The recombinant plasmid pPIC9K-sarr~ was integrated into Pichia pastoris GSl15 genome by electroporation and induced by methanol. The activity of the recombinant enzyme was measured using high-pedormance liquid chroma- tography (HPLC) by determining the production of S-adenosy-L-methionine (SAM) with the enzyme secreted. [ ResultJ The molecular weight of the expression protein identified by SDS-PAGE was about 50 kD, being larger than the theoretical molecular mass of SAMS, which might be due to the glycosytation in the process of secretion. Methanol-induction as well as preliminary purification could enhance the enzyme activity, espe- cially the latter, after which the specific activity of SAMS was improved to 61.48 U/rng. [Conclusion] SAMS with biological activity was secreted successfully in Pichia pastoris GSl15 for the first time. And it is the start for the genetic engineering strains to open up prospects for industrial production.
文摘Objective To investigate the value of BT-H3 in expressed prostatic secretions ( EPS) in differential diagnosis of patients with inflammatory elevation of PSA in t - PSA gray zone ( 4 - 10 ng /ml) . Methods One hundred and sixteen patients from ages of 19 to 80 years ( mean,40 years) were studied. In the group there
基金This work was supported by the Research Council of NorrbottenIn-novationsbron and Langmanska foretagarfonden.J.H.was supported by the Swedish Research Council(No.K2011-65X-3031-01-6)the County Council of Vastra Gotaland(ALF).
文摘The methanol inducible alcohol oxidase 1 promoter and the Saccharomyces cerevisiae alpha-factor prepro secretion signal were used to drive expression and secretion of a mucin-type fusion protein by Pichia pastoris in 1 L scale bioreactors. The aim of the study was to understand how varying expression rates influenced the secretion dynamics of the fusion protein in terms of intracellular- and extracellular concentrations. Endoplasmic reticulum (ER) folding stress was assessed by the relative expression of the unfolded protein response controlled KAR2 gene. Three predefined methanol feeding models were applied to control the fusion protein synthesis rate. To track the fusion protein synthesis in a non-invasive manner and to follow its intracellular distribution, its C-terminal was linked to the green fluorescent protein. Under all conditions the fusion protein was found to partially accumulate intracellularly, where the major fraction was an insoluble, fluorescent full-sized protein. The high degree of glycosylation of the insoluble fusion protein indicated a secretory bottle-neck in the Golgi-system. This result was consistent with low ER folding stress as quantified by the relative expression of the KAR2 gene. Reduction of recombinant protein synthesis rate, by using lower feed rates of methanol, enhanced extracellular concentrations from 8 to 18 mg·L–1 and reduced the rate of intracellular accumulation. This clearly demonstrates the importance of tuning the synthesis rate with secretory bottle-necks to maintain secretion.
基金supported by the Fujian Province Seed Industry Innovation and Industrialization Project“Innovation and Industrialization Development of Precious Tree Seed Industries(Phoebe bornei)”(ZYCX-LY-202102)the Sub-project of National Key R&D Program“Phoebe bornei Efficient Cultivation Technology”(2016YFD0600603-2).
文摘Heat shock transcription factors(Hsfs)have important roles during plant growth and development and responses to abiotic stresses.The identification and func-tion of Hsf genes have been thoroughly studied in various herbaceous plant species,but not woody species,especially Phoebe bournei,an endangered,unique species in China.In this study,17 members of the Hsf gene family were identi-fied from P.bournei using bioinformatic methods.Phyloge-netic analysis indicated that PbHsf genes were grouped into three subfamilies:A,B,and C.Conserved motifs,three-dimensional structure,and physicochemical properties of the PbHsf proteins were also analyzed.The structure of the PbHsf genes varied in the number of exons and introns.Pre-diction of cis-acting elements in the promoter region indi-cated that PbHsf genes are likely involved in responses to plant hormones and stresses.A collinearity analysis dem-onstrated that expansions of the PbHsf gene family mainly take place via segmental duplication.The expression levels of PbHsf genes varied across different plant tissues.On the basis of the expression profiles of five representative PbHsf genes during heat,cold,salt,and drought stress,PbHsf pro-teins seem to have multiple functions depending on the type of abiotic stress.This systematic,genome-wide investigation of PbHsf genes in P.bournei and their expression patterns provides valuable insights and information for further func-tional dissection of Hsf proteins in this endangered,unique species.
基金financially supported by the National Natural Science Foundation of China,No.81303115,81774042 (both to XC)the Pearl River S&T Nova Program of Guangzhou,No.201806010025 (to XC)+3 种基金the Specialty Program of Guangdong Province Hospital of Chinese Medicine of China,No.YN2018ZD07 (to XC)the Natural Science Foundatior of Guangdong Province of China,No.2023A1515012174 (to JL)the Science and Technology Program of Guangzhou of China,No.20210201 0268 (to XC),20210201 0339 (to JS)Guangdong Provincial Key Laboratory of Research on Emergency in TCM,Nos.2018-75,2019-140 (to JS)
文摘Vascular etiology is the second most prevalent cause of cognitive impairment globally.Endothelin-1,which is produced and secreted by endothelial cells and astrocytes,is implicated in the pathogenesis of stroke.However,the way in which changes in astrocytic endothelin-1 lead to poststroke cognitive deficits following transient middle cerebral artery occlusion is not well understood.Here,using mice in which astrocytic endothelin-1 was overexpressed,we found that the selective overexpression of endothelin-1 by astrocytic cells led to ischemic stroke-related dementia(1 hour of ischemia;7 days,28 days,or 3 months of reperfusion).We also revealed that astrocytic endothelin-1 overexpression contributed to the role of neural stem cell proliferation but impaired neurogenesis in the dentate gyrus of the hippocampus after middle cerebral artery occlusion.Comprehensive proteome profiles and western blot analysis confirmed that levels of glial fibrillary acidic protein and peroxiredoxin 6,which were differentially expressed in the brain,were significantly increased in mice with astrocytic endothelin-1 overexpression in comparison with wild-type mice 28 days after ischemic stroke.Moreover,the levels of the enriched differentially expressed proteins were closely related to lipid metabolism,as indicated by Kyoto Encyclopedia of Genes and Genomes pathway analysis.Liquid chromatography-mass spectrometry nontargeted metabolite profiling of brain tissues showed that astrocytic endothelin-1 overexpression altered lipid metabolism products such as glycerol phosphatidylcholine,sphingomyelin,and phosphatidic acid.Overall,this study demonstrates that astrocytic endothelin-1 overexpression can impair hippocampal neurogenesis and that it is correlated with lipid metabolism in poststroke cognitive dysfunction.
基金the grants from the National Basic Research Program of Ministry of Science and Technology, China (973 Program, 2005CB 121000) the Science and Technology Project of Guangdong Province, China (2003C104042) the Natural Science Foundation of Guangdong Province, China (032256, 04020553).
文摘The antifungal peptides, drosomycin (Drs) and its isoform drosomycin-like C (Drs-lC) from Drosophila melanogaster and Thanatin from Podisus maculiventris, have potent activity with broad spectrum against filamentous fungi. Secretive expression of these genes in yeasts makes it possible to utilize the supernatants of yeast culture as protective reagents on fruit, vegetable, food and other agricultural products. So the study of effective secretion by yeast expression system is of great importance. Three genes, Drs, Drs-lC, and Thanatin, were cloned into pPICZαA and the recombinant vectors, pPICZαA-Drs, pPICZαA-Drs-lC, and pPICZαA-Thanatin were transformed into Pichia pastoris by the electric transfer method. The recombinant P. pastoris, which was screened by phenotype selection and PCR amplification, was induced to express antifungal peptide by methanol. The expressive products of the three recombinants showed antifungal activity against 5 out of 6 test fungi strains, and the products of Thanatin also had strong activity against the tested bacteria. The three antifungal peptide genes, Drs, Drs-lC, and Thanatin, were constructed into yeast P. pastoris. The expressed peptides were successfully secreted into the culture medium and exhibited potent activities against the test strains.
基金supported by the National Science Foundation of China (NO. 30800910)
文摘Objective This study is to examine the secretion effects of β-galactosidase in Lactococcus lactis.Methods The usp45 and β-galactosidase genes were cloned and inserted into plasmid pMG36e to obtain the recombinant plasmid pMG36e-usp-lacZ.This recombinant plasmid was transformed into both Escherichia coli DH5α and L.lactis MG1363.The enzyme activity,gene sequencing,SDS-PAGE and hereditary stability were assessed and studied.Results The lacZ gene inserted into plasmids pMG36e-usp-lacZ was 99.37% similar to the GenBank sequence,and SDS-PAGE revealed an evident idio-strap at 116 KDa between L.lactis MG1363/pMG36eusp-lacZ in both supernatant and cell samples.β-Galactosidase activity measured 0.225 U/mL in L.lactis pMG36e-usp-lacZ transformants,and its secretion rate was 10%.The plasmid pMG36e-usp-lacZ appeared more stable in MG1363.Conclusion The authors concluded that these new recombinant bacteria well expressed and secreted β-galactosidase,indicating that the β-galactosidase expression system was successfully constructed,and this might provide a new solution for management of lactose intolerance specifically and promote the use of gene-modified organisms as part of the food-grade plasmid in general.
基金Supported by the Special-purpose Scientific Research Foundation for University Doctorate Project of the Ministry of Education of China, No. 301090255
文摘AIM: To investigate the functions of promoter hypermethylation of secreted frizzled-related proteins (sFRPs) genes in colorectal tumorigenesis and progression. METHODS: The promoter hypermethylation and expression of sFRP genes in 72 sporadic colorectal carcinomas, 33 adenomas, 18 aberrant crypt foci (ACF) and colorectal cancer cell lines RKO, HCT116 and SW480 were detected by methylation-specific PCR and reverse transcription PCR, respectively. RESULTS: None of the normal colorectal mucosa tissues showed methylated bands of any of four sFRP genes, sFRP1, 2, 4 and 5 were frequently methylated in colorectal carcinoma, adenoma and ACF (sFRP1 〉 85%, sFRP2 〉75%, sFRP5 〉 50%), and the differences between three colorectal tissues were not significant (P 〉 0.05). IVlethylation in colorectal tumors was more frequent than in normal mucosa and adjacent normal mucosa. The mRNA of sFRP1-5 genes was expressed in all normal colorectal mucosa samples. Expression of sFRP1, 2, 4 and 5 and sFRP1, 2 and 5 was downregulated in carcinoma and adenoma, respectively. The downregulation of sFRP2, 4 and 5 was more frequent in carcinoma than in adenoma. Expression of sFRP3 which promoter has no CpG island was downregulated in only a few of colorectal tumor samples (7/105). The downregulation ofsFRP1, 2, 4 and 5 expression was significantly associated with promoter hypermethylation in colorectal tumor. After cells were treated by DAC/TSA combination, the silenced sFRP mRNA expression could be effectively re-expressed in colorectal cancer cell lines. CONCLUSION: Hypermethylation of sFRP genes is a common early event in the evolution of colorectal tumor, occurring frequently in ACF, which is regarded as the earliest lesion of multistage colorectal carcinogenesis. It appears to functionally silence sFRP genes expression. Methylation of sFRP1, 2 and 5 genes might serve as indicators for colorectal tumor.
基金the Science and Technology Development Fund of Tianjin Education Commission for Higher Education,No.2020KJ133Tianjin Key Medical Discipline(Specialty)Construction Project,No.TJYXZDXK-009A.
文摘BACKGROUND Cyclin-dependent kinase 9(CDK9)expression and autophagy in colorectal cancer(CRC)tissues has not been widely studied.CDK9,a key regulator of transcription,may influence the occurrence and progression of CRC.The expression of auto-phagy-related genes BECN1 and drug resistance factor ABCG2 may also play a role in CRC.Under normal physiological conditions,autophagy can inhibit tumorigenesis,but once a tumor forms,autophagy may promote tumor growth.Therefore,understanding the relationship between autophagy and cancer,partic-ularly how autophagy promotes tumor growth after its formation,is a key motivation for this research.AIM To investigate the relationship between CDK9 expression and autophagy in CRC,assess differences in autophagy between left and right colon cancer,and analyze the associations of autophagy-related genes with clinical features and prognosis.METHODS We collected tumor tissues and paracarcinoma tissues from colon cancer patients with liver metastasis to observe the level of autophagy in tissues with high levels of CDK9 and low levels of CDK9.We also collected primary tissue from left and right colon cancer patients with liver metastasis to compare the autophagy levels and the expression of BECN1 and ABCG2 in the tumor and paracarcinoma tissues.RESULTS The incidence of autophagy and the expression of BECN1 and ABCG2 were different in left and right colon cancer,and autophagy might be involved in the occurrence of chemotherapy resistance.Further analysis of the rela-tionship between the expression of autophagy-related genes CDK9,ABCG2,and BECN1 and the clinical features and prognosis of colorectal cancer showed that the high expression of CDK9 indicated a poor prognosis in colorectal cancer.CONCLUSION This study laid the foundation for further research on the combination of CDK9 inhibitors and autophagy inhibitors in the treatment of patients with CRC.
基金Supported by Liaoning Education Divison Foundation, No.05L557
文摘AIM: To identify the methylation of secreted frizzled-related protein 1 (SFRP1) in gastric cancer and to investigate the aberrant expression of SFRP1 and its correlation with the clinical pathological features of patients. METHODS: We determined SFRP1 methylation and SFRP1 mRNA expression in 3 gastric cancer cell lines SGC-7901, BGC-823, HGC-27, from 52 primary gastric cancer specimens and matched tumor adjacent tissue specimens by methylation-specific (MSP) PCR and RT-PCR respectively. Fisher's exact test was used to analyze the statistical association between clinical pathological data and aberrant expression of SFRP1. RESULTS: In 3 cancer cell lines, BGC-823 and HGC-27 had methylated SFRP1 and lost SFRP1 mRNA expression. After treatment of BGC-823 and HGC-27 with the demethylating agent, 5-aza-2′-deoxycytidine, SFRP1 was re-expressed. In 52 primary gastric cancer specimens and matched tumor adjacent tissue specimens, hypermethylation of SFRP1 was detected in 23 (44%) and 8 (15%) specimens respectively (x^2= 10.34, P 〈 0.01). Loss of SFRP1 expression was detected in 17(33%) and 6 (12%) specimens respectively (x^2= 6.75, P 〈 0.01). There was a significant correlation between SFRP1 hypermethylation and SFRP1 expression loss. SFRP1 expression was also correlated significantly with tumor stage and lymph node status, but not with patient sex, age and histological type. CONCLUSION: SFRP1 inactivation is a common and early event caused mainly by hypermethylation in gastric cancer. SFRP1 expression loss may be correlated with tumor metastasis in primary gastric cancer.
基金The Fund for University Science and Technology Research from Education Office of Liaoning Province,No.05L557
文摘AIM:To determine the methylation status and aberrant expression of some secreted frizzled-related protein(SFRP) genes in pancreatic cancer and explore their role in pancreatic carcinogenesis.METHODS:Methylation status and expression of SFRP genes were detected by methylation-specific PCR(MSPCR) and reverse-transcription PCR(RT-PCR) respectively.RESULTS:The frequencies of methylation for SFRP genes 1,2,4,5 were 70%,48.3%,60% and 76.7% in pancreatic cancer samples,and 21.7%,20%,10% and 36.7% in matched cancer adjacent normal tissue samples,respectively(χ^2 = 28.23,P 〈 0.0001 for SFRP gene 1;χ^2 = 10.71,P = 0.001 for SFRP gene 2;χ^2 = 32.97,P 〈 0.0001 for SFRP gene 4;χ^2 = 19.55,P 〈 0.0001 for SFRP gene 5).Expression loss of SFRP genes 1,2,4 and 5 was found in 65%,40%,55% and 71.7% of 60 pancreatic cancer samples,and 25%,15%,18.3% and 31.7% of matched cancer adjacent normal tissue samples,respectively(χ^2 = 19.39,P 〈 0.0001 for SFRP gene 1;χ^2 = 9.40,P = 0.002 for SFRP gene 2;χ^2 = 17.37,P 〈 0.0001 for SFRP gene 4;χ^2 = 19.22,P 〈 0.0001 for SFRP gene 5).SFRP gene 1 was methylated but not expressed in PC-3 and PANC-1,SFRP gene 2 was methylated but not expressed in PANC-1 and CFPAC-1,SFRP gene 4 was methylated but not expressed in PC-3,and SFRP gene 5was methylated but not expressed in CFPAC-1.CONCLUSION: Hypermethylation and aberrant expression of SFRP genes are common in pancreatic cancer, which may be involved in pancreatic carcinogenesis.