Polymorphisms in interleukin-10 gene according to mutations of NOD2/CARD15 gene and relation to phenotype in Spanish patients with Crohn's disease

AIM： To examine the contribution of interleukin-10 （IL-10） gene polymorphisms to Crohn＇s disease （CD） phenotype, and the possible genetic epistasis between IL-10 gene polymorphisms and CARD15/NOD2 gene mutations. METHODS： A cohort of 205 Spanish unrelated patients with Crohn＇s disease recruited from a single center was studied. All patients were rigorously phenotyped and followed-up for at least 3 years （mean time, 12.5 years）. The clinical phenotype was established prior to genotyping. RESULTS： The correlation of genotype-Vienna classification groups showed that the Ueocolonic location was significantly associated with the -1082G allele in the NOD2/CARD15 mutation-positive patients （RR = 1.52, 95%CI, 1.21 to 1.91,P= 0.008）. The multivariate analysis demonstrated that the IL-10 G14 microsatellite allele in the NOD2/CARD15 mutation positive patients was associated with two risk factors, history of appendectomy （RR = 2.15, 95%CI = 1.1-4.30, P= 0.001） and smoking habit at diagnosis （RR= 1.29, 95%CI= 1.04-4.3, P= 0.04）. CONCLUSION： In Spanish population from Madrid, in CD patients carrying at least one NOD2/CARD15 mutation, the -1082G allele is assodated with ileocolonic disease and the IL-IOG14 microsatellite allele is associated with previous history of appendectomy and smoking habit at diagnosis. These data provide further molecular evidence for a genetic basis of the clinical heterogeneity of CD.

Association between interleukin-21 gene rs907715 polymorphism and gastric precancerous lesions in a Chinese population

BACKGROUND The single nucleotide polymorphisms of interleukin-21(IL-21)gene were confirmed to be related to various diseases,but no studies have examined the possible role of IL-21 single nucleotide polymorphisms(SNPs)(rs907715,rs2221903,and rs12508721)in gastric precancerous lesions.AIM To explore the associations between SNPs of IL-21 gene(rs907715,rs2221903,and rs12508721)and gastric precancerous lesions in a Chinese population.METHODS Three SNPs of IL-21 were genotyped using polymerase chain reaction–ligase detection reaction in 588 cases and 290 healthy controls from May 2013 to December 2016 in northwestern China.Gastric precancerous lesions were confirmed by endoscopic examination and categorized as non-atrophic gastritis,atrophic gastritis,and intestinal metaplasia.Descriptive statistic and logistic regression were used for data analyses.RESULTS IL-21 rs907715 genotype CC and C frequencies were higher in in patients with gastric precancerous lesions than in the controls(OR=1.59,95%CI:1.06-2.38,P=0.013;OR=1.28,95%CI:1.01-2.22,P=0.044,respectively)after adjusting for confounding factors.For SNP rs907715 in intestinal metaplasia patients,significant differences between cases and controls were observed in the frequencies of genotype CC and C(OR=1.92,95%CI:1.24-2.98,P=0.004;OR=1.53,95%CI:1.04-2.24,P=0.028,respectively);for non-atrophic gastritis and atrophic gastritis patients,the CC and C genotypes showed no significant association with risk in all models.No association between either rs2221903 or rs12508721 and gastric precancerous lesions was found in the present study.In the haplotype analysis,the TC haplotype(rs907715 and rs12508721)and TT haplotype(rs2221903 and rs907715)were more frequent in the case group than control group(P<0.05).CONCLUSION Our findings indicate that SNP rs907715 of IL-21 gene is associated with gastric precancerous lesions.The TC haplotype(rs907715 and rs12508721)and TT haplotype(rs2221903 and rs907715)increased the risk of gastric precancerous lesions.If confirmed,these findings will shed light on the etiology of precancerous lesions.

Diversity of Bmp15 and Gdf9 Genes in White Goat of Guizhou Province and Evolution of the Encoded Proteins

Members of the transforming growth factor-beta superfamily, growth differentiation factor 9 （GDF9） and bone morphogenetic protein 15 （BMP 15）, have crucial roles in fecundity of sheep. Our previous investigation confirmed that the fecundity mutations of sheep presented in highly prolific White goat individuals of Guizhou province. To illuminate other polymorphisms in Bmpl5 and Gdfl） genes and the relationship of these mutations with function, we cloned and characterized the coding region of Bmp15 and Gdfl）. Molecular models of BMP15 and GDF9 mature peptide of White goat were constructed based on the homology of human BMP7 experimental tertiary structure. Two exons encoded prepropeptide of 394 amino acids in BMPI5 and 453 residues in GDF9, respectively. Apart from the FecXs mutation （S99I） in BMP15 and V791 mutation in GDF9 confirmed in White goat previously, other seven and three polymorphism sites were detected from BMP15 and GDF9 mature peptides, respectively. S32G, N66H, S99I/P99I and G107R in BMP15 could be important for the binding of dimer to receptors. Changes of P78Q and V79I in GDF9 might affect the binding of dimer to receptor type t. Comparing the length of BMP 15 and GDF9 prepropeptide in vertebrates, an increase in length of BMP 15 presented along with the protein evolution from fish to mammal and the divergence of the N-terminus residues in matured BMP15 peptide might contribute to the sensitive control on the fertility of animal species with low ovulation rate. These findings gave a valuable explanation for the correlation of mutations in Bmpl5 and Gdfl） genes with the control on fecundity of White goat and supported the notion that they were the pivotal factors in female fertility of White goat in Guizhou province.

Cloning of Rabbit Bone Morphogenetic Protein 15 and Its Expression During in vitro Maturation of Rabbit Oocytes

Partial cDNA sequence of rabbit BMP15 was cloned by RT-PCR from rabbit ovaries, showing a similarity of 83%-90% with the BMP15 nucleotide sequences in humans, mice, ovine, sheep, cows and pigs. The expression of BMP15 in rabbit cumulus-oocyte complexs during oocytes in vitro maturation （IVM） was measured by fluorescent quantitative RT-PCR method. BMP 15 was expressed at low levels in immature oocytes and increased to the highest level at 16h of IVM, which coincides with the time of cumulus cell expansion, then declined slowly under IVM cultivation. The expression pattern of BMP 15 suggested that it might be important in cumulus expansion in rabbits.

鼻咽癌组织SNHG15和LINC00261的表达及其临床意义

目的:探讨鼻咽癌中小核仁RNA宿主基因15(SNHG15)和LINC00261的表达水平及其临床意义。方法:收集2018年1月至2020年2月本院93例行鼻咽癌根治性切除术患者的鼻咽癌组织和癌旁组织样本以及临床资料;培养鼻咽癌CNE-1细胞和正常鼻咽部上皮NP69细胞,分为空白对照组、shRNA-NC组(转染SNHG15对照)、SNHG15-shRNA组(转染SNHG15)、pcDNA-NC组(转染LINC00261对照)、LINC00261-pcDNA组(转染LINC00261);采用RT-qPCR检测SNHG15和LINC00261表达水平;采用CCK-8和克隆形成实验检测各组细胞的增殖情况;采用Pearson法分析组织中SNHG15和LINC00261表达水平的相关性;采用Kaplan-Meier法分析鼻咽癌组织SNHG15和LINC00261表达水平与患者预后的关系;采用多因素Cox回归分析影响鼻咽癌患者预后的相关因素。结果:鼻咽癌组织中SNHG15表达水平高于癌旁组织,LINC00261表达水平则低于癌旁组织;鼻咽癌组织中SNHG15和LINC00261表达水平呈负相关。CNE-1细胞中SNHG15表达水平高于NP69细胞,LINC00261表达水平则低于NP69细胞;SNHG15-shRNA组和LINC00261-pcDNA组CNE-1细胞克隆形成数量均低于空白对照组、shRNA-NC组及pcDNA-NC组,细胞增殖能力降低。不同SNHG15和LINC00261表达水平的鼻咽癌患者年龄、肿瘤直径及组织学类型差异无统计学意义,而SNHG15高表达组及LINC00261低表达组发生淋巴结转移、TNM分期为Ⅲ+Ⅳ期的患者所占比例显著高于SNHG15低表达组及LINC00261高表达组;SNHG15低表达患者3年生存率(84.78%)显著高于SNHG15高表达患者(65.95%),LINC00261低表达患者3年生存率(63.04%)显著低于LINC00261高表达患者(87.23%)。结论:鼻咽癌组织中SNHG15和LINC00261表达与患者临床病理特征及预后密切相关,淋巴结转移、TNM分期及SNHG15是鼻咽癌患者死亡的危险因素,而LINC00261是鼻咽癌患者死亡的保护因素。

ANTITUMOR EFFECTS OF HUMAN IL-15 GENE MODIFIED LUNG CANCER CELL LINE

Human IL15 cDNA fragment, which contains all codons encoding the human IL15 mature protein and signal peptide was transducted into the human lung squmouse cancer cells(PG cells) and murine lung adenocarcinoma cells(LA795 cell lines). Two IL15 highly expressed cell clones PG1 and LA795A were used to inoculate the nude mice and the T739 syngeneic mice respectively. PG1 cell express higher level of class ⅠMHC molecule on their surface than PG cells. It was shown that the modified LA795A tumor cells grew slowly in T739 mice and induced high levels of CTL/NK/LAK activity in vivo as well, compared with the case of inoculation with LA795 or LA795neo. No significant difference in the tumor growth was observed in groups of the nude mice inoculated by PG1, PG and PGneo cells respectively, except the gene modified cells could not show the lung metastasis of tumors. The supernatants derived from the LA795A cell culture could promote CTL/NK/LAK activity from the whole splenocytes and the CD4/CD8deleted splenic cells in vitro. The results indicated that the IL15 gene transfected tumor cells play important roles in the process of antitumor or antitumor metastasis.

Association of polymorphisms of interleukin-18 gene promoter region with chronic hepatitis B in Chinese Han population

AIM: To investigate the polymorphisms of interleukin-18 (IL-18) gene promoters, and to disclose whether such polymorphisms are associated with susceptibility to chronic hepatitis B in Chinese Han population. METHODS: Using polymerase chain reaction with sequence specific primers (PCR-SSP) method, the single nucleotide polymorphisms (SNPs) of the promoter region of IL-18 gene at position -607 and -137 were detected in 231 patients with chronic hepatitis B and 300 normal controls. RESULTS: Allele C at position -607 in the promoter of IL-18 gene was detected in 48.7% of normal controls and 51.9% of patients, while allele A at position -607 was detected in 51.3% of normal controls and 48.1% of patients. The frequencies of -607CC, -607 CA and -607AA genotypes in normal controls were 22.0%, 53.3% and 24.7% respectively and in chronic hepatitis B patients were 26.8%, 50.2% and 23.0% respectively. Allele G at position -137 in the promoter of IL-18 gene was detected in 82.3% of normal controls and 88.5% of chronic hepatitis B patients, while allele C at position -137 was detected in 17.7% of normal controls and 11.5% of patients. The frequencies of -137GG, GC and CC genotype were 67.3%, 30.0% and 2.7% in normal controls respectively, while in chronic hepatitis B patients were 78.8%, 19.5% and 1.7% respectively. The frequency of-137GG genotype in chronic hepatitis B groups was significantly higher than that in normal controls (x2=8.55, P=0.003 <0.05), whereas the frequencies of -607C/-137C and -607A/-137C haplotypes in chronic hepatitis B groups were significantly lower than that in normal controls. The association between genotypes of IL-18 promoter region polymorphisms and HBV copies showed that the frequency of -607AA genotype in high HBV-DNA copies groups was lower than that in low HBV-DNA copies groups (x2=6.03, P=0.014 <0.05). CONCLUSION: The polymorphisms of the promoter region of IL-18 gene at position -607 and -137 are closely associated with susceptibility to chronic hepatitis B. The people with allele C at position -137 in the promoter of IL-18 gene may be protected against HBV infection; moreover AA genotype at position -607 may be closely linked to inhibit HBV-DNA replication. These findings give some new clues to the study of pathogenesis of chronic hepatitis B.

Polymorphism of p16INK4a gene and rare mutation of p15INK4b gene exon2 in primary hepatocarcinoma

INTRODUCTION Hepatocellular carcinoma(HCC)is the mostcommon cause of death from cancer in China.Themechanisms of hepatocarcinogenesis are not yetknown clearly,p16INK4a gene,the multiple tumorsuppressor gene 1(MTS1),encodes P16 protein,which acts as an inhibitor by binding directly toCDK4 and CDK6 and preventing its association

Interleukin-1β gene polymorphism associated with hepatocellular carcinoma in hepatitis B virus infection

AIM： To examine the effect of interleukin-l-beta （IL-113） promoter region C-511T and IL-1 receptor antagonist （IL-1RN） polymorphism among the patients with chronic hepatitis B virus （HBV） infection （HCC and non-HCC）. METHODS： Genomic DNA from 136 Thai patients with chronic HBV infection （HCC =46 and non-HCC= 90） and 152 healthy individuals was genotyped for IL-113 gene polymorphism （-511） using polymerase chain reaction with sequence specific primers （PCR-SSP）. The variable number of tandem repeats （VNTR） of IL-1RN gene was assessed by a PCR-based assay. The association between these genes and status of the disease was evaluated by X^2 test. RESULTS： IL-1B-511 genotype c/c was found to be significantly different in patients with HCC when compared with healthy individuals （P = 0.036, OR = 2.29, 95%CI = 1.05-4.97） and patients without HCC （P=0.036, OR= 2.52, 95%CI=1.05-6.04）. Analysis of allele frequencies of IL-1B-511 showed that IL-1B-511 C allele was also significantly increased in patients with HCC, compared to that in healthy control （P=0.033, OR= 1.72, 95%CI=1.04-2.84）. However, no significant association in IL-1RN gene was found between the two groups. CONCLUSION： IL-1B-511C allele, which may be associated with high IL-1B production in the liver, is a genetic marker for the development of HCC in chronic hepatitis B patients in Thai population.

OCTN and CARD15 gene polymorphism in Chinese patients with inflammatory bowel disease

AIM： To investigate the single nucleotide polymorphism （SNPs） distribution of NOD2/CARD15 （R702W, G908R）, OCTN1 1672CFT and OCTN2-207G/C in Chinese patients with inflammatory bowel disease （IBD）. METHODS： A total of 61 patients with Crohn＇s disease （CD）, 151 patients with ulcerative colitis （UC）, and 200 unrelated healthy controls were genotyped. Genotyping was performed by sequence specific primer polymerase chain reaction （PCR-SSP） or by restriction fragment length polymorphism （PCR-RFLP） analysis. RESULTS： Among the subjects in our study groups, including patients with CD, UC and healthy controls, none had OCTN and CARD15 variants and very rare IBD family history was found in our patients with the percentage of 0 （0/61 with CD） and 1.3% （2/151 with UC）. CONCLUSION： Our results indicate that although OCTN or CARD15 variation is associated with susceptibility to IBD in Western populations, these might be rare and may not be associated with susceptibility to IBD in Chinese patients.

Clinical significance of NOD2/CARD15 and Toll-like receptor 4 gene single nucleotide polymorphisms in inflammatory bowel disease

AIM： To evaluate the role of genetic factors in the pathogenesis of Crohn＇s disease （CD） and ulcerative colitis （UC）, we investigated the single nucleotide polymorphisms （SNPs） of NOD2/CARD15 （R702W, Gg08R and L1007finsC）, and Toll-like receptor 4 （TLR4） genes （D299G and T399I） in a selected inflammatory bowel disease （IBD） population coming from Southern Italy. METHODS： Allele and genotype frequencies of NOD2/ CARD15 （R702W, Gg08R and L1007finsC） and TLR4 （D299G and T399I） SNPs were examined in 133 CD patients, in 45 UC patients, and in 103 healthy controls. A genotype-phenotype correlation was performed. RESULTS： NOD2/CARD15 R702W mutation was significantly more frequent in CD （9.8%） than in controls （2.4%, P = 0.001） and in UC （2.3%, P = 0.03）. No significant difference was found between UC patients and control group （P 〉 0.05）. In CD and UC patients, no significant association with G908R variant was found. L1007finsC SNP showed an association with CD （9.8%） compared with controls （2.9%, P = 0.002） and UC patients （2.3%, P = 0.01）. Moreover, in CD patients, G908R and L1007finsC mutations were significantly associated with different phenotypes compared to CD wild-type patients. No association of IBD with the TLR4 SNPs was found in either cohort （allele frequencies： D299G-controls 3.9%, CD 3.7%, UC 3.4%, P 〉 0.05; T399I-controls 2.9%, CD 3.0%, UC 3.4%, P 〉 0.05）. CONCLUSION： These findings confirm that, in our IBD patients selected from Southern Italy, the NOD2/ CARD15, but not TLR4 SNPs, are associated with increased risk of CD.

Involvement of interleukin-15 and interleukin-21, two γ-chain-related cytokines, in celiac disease

Celiac disease (CD), an enteropathy caused by dietary gluten in genetically susceptible individuals, is histologically characterized by villous atrophy, crypt cell hyperplasia, and increased number of intra-epithelial lymphocytes. The nature of CD pathogenesis remains unclear, but recent evidence indicates that both innate and adaptive immune responses are necessary for the phenotypic expression and pathologic changes characteristic of CD. Extensive studies of molecules produced by immune cells in the gut of CD patients have led to identification of two cytokines, namely interleukin (IL)-15 and IL-21, which are thought to play a major role in orchestrating the mucosal inflammatory response in CD. Here we review the current knowledge of the expression and function of IL-15 and IL-21 in CD.

Role of CARD15,DLG5 and OCTN genes polymorphisms in children with inflammatory bowel diseases

AIM: To investigate the contribution of variants of CARD15, OCTN1/2 and DLG5 genes in disease predispo- sition and phenotypes in a large Italian cohort of pediatric patients with inflammatory bowel diseases (IBD). METHODS: Two hundred patients with Crohn’s disease (CD), 186 ulcerative colitis (UC) patients, 434 par- ents (217 trios), and 347 healthy controls (HC) were studied. Polymorphisms of the three major variants of CARD15, 1672C/T and -207G/C SNPs for OCTN genes, IGR2096a_1 and IGR2198a_1 SNPs for the IBD5 locus, and 113G/A variant of the DLG5 gene were evaluated. Potential correlations with clinical sub-phenotypes were investigated. RESULTS: Polymorphisms of CARD15 were significantly associated with CD, and at least one variant was found in 38% of patients (15% in HC, OR = 2.7, P < 0.001). Homozygosis for both OCTN1/2 variants was more com- mon in CD patients (1672TT 24%, -207CC 29%) than in HC (16% and 21%, respectively; P = 0.03), with an in- creased frequency of the TC haplotype (44.8% vs 38.3% in HC, P = 0.04). No association with the DLG5 variant was found. CD carriers of OCTN1/2 and DLG5 variants more frequently had penetrating disease (P = 0.04 and P = 0.01), while carriers of CARD15 more frequently had ileal localization (P = 0.03). No gene-gene interaction was found. In UC patients, the TC haplotype was morefrequent (45.4%, P = 0.03), but no genotype/phenotype correlation was observed. CONCLUSION: Polymorphisms of CARD15 and OCTN genes, but not DLG5 are associated with pediatric on- set of CD. Polymorphisms of CARD15, OCTN, and DLG5 genes exert a weak influence on CD phenotype.

DELETIONS AND POINT MUTATIONS OF p16,p15 GENE IN PRIMARY TUMORS AND TUMOR CELL LINES

Aberrations of chromosome 9 p21 22 are involved in the genesis of many forms of cancer.The gene p16 and p15 have been assigned to this region.Both p16 and p15 are an inhibitor of cyclin D cdk4,cyclin D cdk6 complex and have been implicated in a wide variety of cancer types,including the germline of patients with familial melanoma.In order to investigate and compare the status of p16,p15 gene in primary tumors and cell lines,we examined 357 primary tumors and 29 cell lines derived from diverse tumor types.In addition to analysis of these primary tumors and cell lines,blood specimens from 91 patients either with sporadic multiple cancers or from cancer prone families were also analyzed.The data showed the following:1)Homozygous deletions of p16,p15 were comparatively rare and far less common than previously reported,although hemizygous deletions were observed in a significant fraction of many tumor types;2)the incidence of p16,p15 deletions(either homozygous deletions or heterozygous deletions)varied significantly among different tumor types;3)most deletions involved in both p16 and p15 genes;4)sequence variations in the coding sequence of p16,p15 were comparatively rare among these tumor types,though mutations and polymorphisms were identified;5)some tumors which showed LOH at 9p,containing p16 and p15 gene,did not show deletions or point mutations in the p16,p15 gene.6)In a subset of retinoblastoma and osteosarcoma where no Rb gene mutations were present a significant fraction was found to contain p16,p15 gene deletions.

Interleukin-8 gene polymorphism is associated with acute coronary syndrome in a Han Chinese population

Background Acute coronary syndrome(ACS) is one of the most common forms of heart diseases.Recent studies have revealed that interleukin(IL)-8 plays a kev role in the development of atherosclerosis plaque and its complications, but the relationship of its common variants with ACS has not been extensively studied.Methods We tested the hypothesis that variants in IL-8-251 A/T was associated with susceptibility to ACS and its recurrence in a Chinese case-control study comprising 675 patients with ACS and 636 control subjects and replicated the investigation in an independent study comprising 360 cases and 360 control subjects. The plasma concentration of IL-8 was measured by enzyme-linked immunosorbent assay.Results IL-8 -251A】T poly-morphism was associated with increased susceptibility to ACS (P=0.004;OR=1.30 CI:1.12-1.53).Replication in the second study yielded similar results.IL-8 -251 A/T may affect the expression of IL-8 by the evidence that augmented IL-8 production revealed in serum of the AMI patients by ELISA. Conclusions IL-8 -251 A/T polymorphism is associated with ACS risk in Chinese Han population and An allele of IL-8- 251A/T may be an independent predictive factor.

Interleukin-17A gene variants and risk of coronary artery disease:a large angiography-based study

Background Recent studies have also revealed that interleukin(IL)-17A plays a key role in atherosclerosis and its complication,but the relationship of its common variants with coronary artery disease(CAD) has not been extensively studied.Methods We systematically screened sequence variations in the IL17A gene and designed an angiog-raphy -based case-controlled study consisting of 1031 CAD patients and 935 control subjects to investigate the association between the selected polymorphisms of IL-17A gene and CAD risk in Chinese Han population.Results Frequencies of IL17A rs8193037 GG homozygote and G allele were significantly higher in the patient group than those in the control group(P【0.001;OR=0.68;95%CI=0.54-0.85).Stratification analysis showed that the IL17A rs8193037 G allele significantly increased the risk of CAD only among male subjects (P=0.001;OR=0.63;95%CI=0.47-0.83).After adjustment for conventional risk factors,binary logistic regression analysis showed that the G allele carriers(GG +AG) had significantly increased CAD risk compared with the AA homozygotes (adjusted P【0.001;OR 0.43;95%CI,0.33- 0.58).ELISA showed augmented IL17A production in plasma of the AMI patients.Conclusions Based on our data,we speculated that the SNP rs8193037 of IL17A gene is significantly associated with CAD risk in Chinese Han population and the rs8193037 G allele which is associated with increased expression of IL17A in AMI patients may be an independent predictive factor for CAD.

MEK AND p38 MAPK-DEPENDANT PATHWAYS ARE INVOLOVED IN THE POSITIVE EFFECT OF INTERLEUKIN-6 ON HUMAN GROWTH HORMONE GENE EXPRESSION IN RAT MtT/S SOMATOTROPH CELLS

Objective To investigate the effect of interleukin-6(IL-6)on the human growth hormone(hGH)gene expression in a rat somatotropic pituitary cell line MtT/S.Methods The plasmids containing various lengths of hGH gene 5'-promoter fragments were constructed.Stably transfected MtT/S cells were created by cotransfecting the above plasmids and pcDNA3.1(+)with DMRIE-C transfection reagent.After the administration of these cells with IL-6 and/or various inhibitors of signaling transduction pathways,the luciferase activities in MtT/S cells lysis were assayed to demonstrate the effects of IL-6 on hGH gene promoter activity and possibly involved mechanism.Results The 103 U/mL IL-6 stimulated GH secretion and synthesis,and promoted the 5'-promoter activity of GH gene in stably transfected MtT/SGL cells with the action of 1.69 times above the control.Among inhibitors of signaling transduction pathways,mitogen-activated protein kinase kinase(MAPKK/MEK)inhibitor PD98059(40 μmol/L)and p38 mitogen-activated protein kinase(MAPK)inhibitor SB203580(5 μmol/L)completely blocked the stimulatory effect of IL-6.Western blot analysis further confirmed the activation of phosphorylated MEK and p38 MAPK in MtT/SGL cells.Neither over-expression of Pit-1 nor inhibition of Pit-1 expression affected IL-6 induction of hGH promoter activity.A series of deletion constructs of hGH promoter were created to identify the DNA sequence that mediated the effect of IL-6.The results showed that the stimulatory effect of IL-6 was abolished following deletion of the-196 to-132 bp fragment.Conclusions IL-6 promotes GH secretion and synthesis by rat MtT/S somatotroph cells.The stimulatory effect of IL-6 on hGH gene promoter appears to require the activation of MEK and p38 MAPK,and a fragment of promoter sequence that spans the-196 to-132 bp of the gene,but may be unlinked with Pit-1 protein.

EFFECT OF INTERLEUKIN-1β ON GROWTH HORMONE GENE EXPRESSION AND ITS POSSIBLE MOLECULAR MECHANISM IN RAT MtT/S SOMATOTROPH CELLS

Objective To elucidate the effect of interleukin-1β （IL- 1β） on human growth hormone （hGH） gene expression in a rat somatotropic pituitary cell line MtT/S. Methods Stably transfected MtT/S cells were firstly established by transfecting 484-Lucl plasmid which contained hGH gene promoter --484 to ＋30 bp and luciferase reporter gene. The effect of IL-1β on hGH gene expression was determined by assaying the luciferase activities. RT-PCR method was also used to determine whether IL-1 recepor mRNA was expressed in MtT/S cells. Results The 10^3 U/mL IL-1β stimulated secretion and synthesis of GH, and promoted the 5＇-promoter activity of GH gene in stably transfected MtT/SGL cells with the action of 1.38 times above the control. Among inhibitors of signaling transduction pathways, mitogen-activated protein kinase kinase （MAPKK/MEK） inhibitor PD98059 （40 μmol/L） and p38 mitogen-activated protein kinase （MAPK） inhibitor SB203580 （5 μmol/L） completely blocked the stimulatory effect of IL-1μ, and phosphatidylinositol-3-kinase （PI3-K） inhibitor LY294002 partly abolished the effect of IL-1μ. Western blot analysis further confirmed the activation of phosphorylated MEK and p38 MAPK in MtT/SGL cells. Neither over-expression of Pit- 1 nor inhibition of Pit- 1 expression affected induction of hGH promoter activity by IL-1μ. A series of deletion constructs of hGH promoter were created to identify the DNA sequence that mediated the effect of IL-1β, and results showed that the stimulatory effect of IL-1β was abolished following deletion of the --196 to -- 132 bp fragment. Conclusions IL-1β promotes GH secretion and synthesis in rat MtT/S somatotroph cells. The stimulatory effect of IL-1β on hGH gene promoter appears to require the activation of MEK, p38 MAPK, PI3-K, and a fragment of promoter sequence that spans the -196 to -132 bp of the gene, but it may be unlinked with Pit-1 protein.

Expression of Interleukin-15 and Its Receptor on the Surface of Stimulated Human Umbilical Vein Endothelial Cells

Summary： Human interleukin-15 （hIL-15） is an important cytokine to activate endothelial cells and can be regulated by many other cytokines. The aim of this study is to examine the ability of interferon-γ （IFN-γ）, and tumor necrosis factor-or （TNF-α to induce the production of human interleukin-15 （hIL-15） and IL-15 receptor （IL-15Rα by human umbilical vein endothelial cells （HUVECs）. The data are summarized as follows： 1. Northern blot revealed that IL-15 mRNA was up-regulated by IFN-γ and TNF-α 2. Intracellular IL-15 protein was visualized by fluorescence microscopy, whereas the expression of IL-15 on the surface of HUVECs was detected by fluorescence activated cell sorting （FACS）, and no detectable IL-15 in the medium was verified by ELISA. 3. IL-15Rα was detected on the surface of HUVECs by FACS after IFN-α and TNF-α stimulation, whereas Western blotting revealed that the elevated expression on surface IL-15Rα was not due to the increased protein expression. The conclusion demonstrated from our results is that IFN-α and TNF-α play an important role in regulating the expression of IL-15 and IL-15Rα on the surface of HUVECs.