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ObjectiveThere are few studies on whether the occurrence of anti-tuberculosis drug-induced liver injury (ADIH) is associated with the polymorphism of CYP2E gene and methylation level. This study aims to CYP2E1 gene polymorphism and the relationship between the methylation level of the promoter region and ADIH in Mongolian tuberculosis (TB) patients.Methods A total of 135 Mongolian TB patients who received standardized treatment at the Tuberculosis Research Institute of Tongliao City, Inner Mongolia from November 2015 to June 2018 were selected. According to the ADIH criteria, TB patients with liver injury were selected as the ADIH group (n=45), and TB patients without liver injury were matched as the control group based on a ratio of 1∶2 (n=90). DNA extraction and polymerase chain reaction (PCR) were performed to amplify the CYP2E1 gene to determine the CYP2E1 rs2031920 genotype, and to analyze the CYP2E1 gene polymorphism and relationship between ADIH and promoter methylation level.Results There were no significant differences in the distribution of CYP2E1 rs2031920 genotype, C1 and C2 gene frequencies between the ADIH group and the control group (P>0.05). The overall methylation level in the promoter region of CYP2E1 gene in ADIH group (0.711±0.085) was significantly lower than that of the control group (0.759±0.062). Results of Logistic regression showed that the overall methylation level in the promoter region of CYP2E1 gene was the influencing factor for the occurrence of ADIH (P<0.005). For each 0.1 unit increase of methylation level, the risk of ADIH occurrence reduced by 0.388 times, and the OR (95% CI) value was 0.388 (between 0.204 and 0.739).Conclusion The overall methylation level in the promoter region of CYP2E1 gene was reduced in Mongolian ADIH patients, but the polymorphism of CYP2E1 gene was not related to the occurrence of ADIH. These results suggested that CYP2E1 methylation could be applied to the prevention and treatment of ADIH in patients with tuberculosis.
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ObjectiveThere are few studies on whether the occurrence of anti-tuberculosis drug-induced liver injury (ADIH) is associated with the polymorphism of CYP2E gene and methylation level. This study aims to CYP2E1 gene polymorphism and the relationship between the methylation level of the promoter region and ADIH in Mongolian tuberculosis (TB) patients.Methods A total of 135 Mongolian TB patients who received standardized treatment at the Tuberculosis Research Institute of Tongliao City, Inner Mongolia from November 2015 to June 2018 were selected. According to the ADIH criteria, TB patients with liver injury were selected as the ADIH group (n=45), and TB patients without liver injury were matched as the control group based on a ratio of 1∶2 (n=90). DNA extraction and polymerase chain reaction (PCR) were performed to amplify the CYP2E1 gene to determine the CYP2E1 rs2031920 genotype, and to analyze the CYP2E1 gene polymorphism and relationship between ADIH and promoter methylation level.Results There were no significant differences in the distribution of CYP2E1 rs2031920 genotype, C1 and C2 gene frequencies between the ADIH group and the control group (P>0.05). The overall methylation level in the promoter region of CYP2E1 gene in ADIH group (0.711±0.085) was significantly lower than that of the control group (0.759±0.062). Results of Logistic regression showed that the overall methylation level in the promoter region of CYP2E1 gene was the influencing factor for the occurrence of ADIH (P<0.005). For each 0.1 unit increase of methylation level, the risk of ADIH occurrence reduced by 0.388 times, and the OR (95% CI) value was 0.388 (between 0.204 and 0.739).Conclusion The overall methylation level in the promoter region of CYP2E1 gene was reduced in Mongolian ADIH patients, but the polymorphism of CYP2E1 gene was not related to the occurrence of ADIH. These results suggested that CYP2E1 methylation could be applied to the prevention and treatment of ADIH in patients with tuberculosis.
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ABSTRACT BACKGROUND: There is evidence that genetic predisposition and epigenetic alteration (e.g. DNA methylation) play major roles in lung cancer. In our genetic epidemiological studies, rs1970764 in oncogene PPP1R13L was most consistently associated with lung cancer risk. Here, we explored the role of PPP1R13L methylation in lung cancer development. DESIGN AND SETTING: Analytical cross-sectional study (45 lung cancer cases and 45 controls), conducted in China. METHODS: We investigated the DNA methylation status of 2,160 cytosine-phosphate-guanine (CpG) sites in the PPP1R13L promoter region using the EpiTYPER assay of the Sequenom MassARRAY platform. RESULTS: In the whole study group, the methylation levels of CpG-6, CpG-9, CpG-20 and CpG-21 were significantly lower and those of CpG-16 were significantly higher in cases than in controls. Among smokers, the methylation levels at five CpG sites (CpG-6, CpG-11, CpG-15, CpG-20 and CpG-21) were statistically significantly lower among cases. Among men, the methylation levels at four CpG sites (CpG-11, CpG-15, CpG-20 and CpG-21) were significantly lower among cases. Regarding smokers, the methylation levels at CpG-7.8 and CpG-21 among cases and at CpG-22 among controls were significantly lower, compared with nonsmokers. The frequency of positivity for methylation was not significantly different between lung cancer cases and controls (68.22% for cases and 71.87% for controls; P = 0.119). CONCLUSION: Our study on a Chinese population suggests that lung cancer patients have aberrant methylation status (hypomethylation tended to be more frequent) in peripheral blood leukocytes at several CpG sites in the PPP1R13L promoter region and that exposure to smoking may influence methylation status.
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Humans , Male , Female , Middle Aged , Aged , Repressor Proteins/genetics , DNA Methylation/genetics , Genetic Predisposition to Disease/genetics , Intracellular Signaling Peptides and Proteins/genetics , Lung Neoplasms/genetics , Case-Control Studies , Cross-Sectional Studies , Promoter Regions, GeneticABSTRACT
Objective@#To investigate the single nucleotide polymorphisms (SNPs) of rs600231A/G and rs4102217 G/C in the promoter region of MALAT1 (metastasis associated in lung adenocarcinoma transcript 1) gene in the healthy population of Guangxi district and analyze the differences in the population among different regions. @*Methods@#The genotypes of rs600231A/G and rs4102217G/C of 207 healthy individuals in Guangxi were detected by SNPscan high-throughput technique. The genotype and allele frequency distributions were analyzed statistically with the data of HapMap-CEU (European population), HapMap-HCB (Beijing Han population), HapMap-JPT (Japanese population) and HapMap-YRI (African population) published by Human genome Haplotype Map (HapMap). @*Results@#There were three genotypes of AA (38.2%), AG (46.4%) and GG (15.4%) in rs600231A/G, and the differences were significantly different compared with the polymorphism of Japan and Africa population (HapMap-JPT and HapMap-YRI) (P＜0.05). Compared with HapMap-CEU, the genotype difference was not statistically significant (P＞0.05), but the allele distribution was statistically different (P＜0.05). The rs4102217 G/C polymorphism contained GG(75.4%), CG(23.2%) and CC(1.4%), and the polymorphisms were significantly different from those in European and Japanese populations (P＜0.05). There was no significant difference between gender in the polymorphisms of the two loci (P＞0.05). @*Conclusion@#The polymorphisms of rs600231A/G and rs4102217G/C in the MALAT1 promoter region were found in Guangxi healthy population, and the distribution of polymorphisms may be different in the population of various regions. @*@#
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OBJECTIVE:To investigate the expression difference and its mechanism of miR-497 and miR-34a in platinum-sen-sitive and platinum-resistant epithelial ovarian carcinoma(EOC)patients. METHODS:A total of 72 EOC patients underwent ovari-an cancer staging surgery or cytoreductive surgery were selected from department of gynaecology and obstetriscs of our hospital dur-ing Jan. 2008-Jan. 2012. They received standardized platinum chemotherapy after surgery and were followed up (during Jul.2008-Jul.2016). According to the sensitivity to platinum,those patients were divided into platinum-sensitive group (42 cases) and platinum-resistant group (30 cases) . Real-time fluorescent quantitative PCR was adopted to detect the expression of miR-497 and miR-34a in tumor tissue,and the relationship of it with total survival period was investigated. The levels of DNA methylation of miR-497 and miR-34a promoter region were determined by nest type land type methylation specific PCR. Western blot assay was used to detect the H3K9 dimethylation(H3K9me2)levels. The H3K9me2 levels of miR-497 and miR-34a promoter region were de-termined by chromatin immunoprecipitation method. RESULTS:The expression levels of miR-497 and miR-34a in platinum-sensi-tive group were significantly higher than platinum-resistant group,with statistical significance (P0.05). CONCLUSIONS:The expression of miR-497 and miR-34a in tumor tissue of EOC patients are related to the sensitivity of platinum chemotherapy and the survival time of patients. DNA methylation and histone methylation of promoter region may be one of the mechanisms of their expression changes.
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Objective To investigate the relationship between HBV mutations in the precore (PC)/core promoter region and the liver histological changes in HBeAg negative CHB patients. Method A total of 71 HBeAg negative CHB patients with liver biopsy from April 2012 to Dec 2013 were enrolled. DNA was extracted from blood serum, then the HBV S gene and PC/core promoter region were amplified by semi-nested PCR and sequenced. The relationship between significant liver histological changes and viral factors were analyzed by Logistic regression analysis. Results The incidence of significant necroinflammation (15.8% vs. 27.3%, χ2 =1.398, P = 0.237) and significant fibrosis (71.1% vs. 84.4%, χ2= 1.926, P = 0.165) were found to be similar between patients infected with HBV genotype B and genotype C . By Logistic regression analysis including risk factors of age, sex, HBV genotype and mutations (T1753V,A1762T/G1764A,A1846T and G1896A), the A1762T/G1764A mutation in HBV associated with significant necroinflammation (OR = 4.296, P = 0.037), while factors of age, sex, genotype and other mutation were not associated with significant liver histological changes. (all P > 0.05). Conclusion Mutation in PC/core promoter region of HBV may act as a marker to evaluate the liver histological changes.
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Objective To explore the correlation between mutations in the promoter region of TBX1 gene and conotruncal heart defects. Methods A total of 621 children with conotruncal heart defects were recruited. Multiplex ligation-dependent probe ampliifcation (MLPA) was used to detect the copy numbers of chromosomal region 22 q 11 . 2 . Children with 22 q 11 . 2 deletion were excluded. Polymerase chain reaction ampliifcation (PCR) and gene sequencing were applied to analyze promoter region of TBX 1 (-2000 ..+1 ) in 605 children with conotruncal heart defects without 22 q 11 . 2 deletion and 588 healthy children. Bioinformatics software was used to predict and analyze the function of the variable loci. Results There were mutations in the promoter region of TBX 1 gene in children with conotruncal heart defects, including 3 single nucleotide polymorphisms (SNP) sites and 7 rare loci. The incidence of mutation was 1 . 7%. The analysis of 7 rare loci by AliBaba 2 . 1 to showed that 3 of them may inlfuence the combination of trans-acting factors and cis-acting elements of the promoter of TBX 1 gene. Conclusion The mutation in the TBX 1 promoter region may be related to the occurrence of conotruncal heart defects.
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Background Exfoliation syndrome (XFS) is a systemic disease with abnormal accumulation of extracellular matrix.Researches showed that the single nucleotide polymorphisms (SNPs) of lysyl oxidase-like 1 (LOXL1) gene is associated with the pathogenesis of XFS in global population.However,the results are varied among different ethnicity and regions.Objective This study aimed to assess the association between LOXL1 gene polymorphisms and XFS in Uygur population.Methods One-hundred and fifty-two Uygur XFS patients without relativeness were enrolled from January to August in 2014,and 228 ethnicity-and gender-matched normal controls were recruited at the same period from the same region.Each individual underwent comprehensive eye examinations and 5 ml peripheral blood was collected.Genomic DNA was extracted from peripheral blood.PCR-ligase detection response (LDR) was used to determine the allele and genotype frequencies of the six SNPs rs12914489,rs4886467,rs4558370,rs4461027,rs4886761 and rs16958477 in the promoter region of LOXL1 gene.The distribution frequency between the patients and normal controls was compared by x2 test.Logistic regression analysis was used for age adjustment.This study was approved by Ethic Committe of Xinjiang Medical University,and informed consent was obtained from the subjects.Results rs12914489 site in the normal control group diverged from Hardy-Weinberg equilibrium (HWE) (P =0.033),and the rs4886467,rs4558370,rs4461027,rs4886761 and rs16958477 sites followed HWE.The frequencies of G allele and GG genotype of rs4886467 in the XFS group were lower than those in the control group (both at P =0.00) and were protective factors of XFS (OR =0.54,95 ％ CI:0.40-0.74,P =0.000;OR=0.51,95％ CI:0.33-0.78,P=0.001);the frequencies of T allele and TT genotype of rs4558370 in the XFS group were significantly higher than those in the control group (both at P=0.00) and were the risk factors of XFS (OR=1.96,95％ CI:1.23-3.11,P =0.004;OR =2.18,95％ CI:1.31-3.64,P =0.002);the frequencies of C allele and CC genotype of rs4461027 in the XFS group were significantly higher than those in the control group (both at P=0.00) and were the risk factors of XFS (OR=2.25,95％ CI:1.67-3.04,P=0.000;OR=3.06,95％ CI:1.89-4.96,P=0.000);the frequencies of T allele and TT genotype of rs4886761 in the XFS group were significantly higher than those in the control group (both at P=0.00) and were the risk factors of XFS (OR=2.44,95％ CI:1.79-3.33,P =0.000;OR =3.02,95％ CI:1.63-5.60,P =0.000);the frequencies of C allele and CC genotype of rs16958477 in the XFS group were significantly higher than those in the control group (both at P=0.00) and were the risk factors of XFS (OR =2.00,95 ％ CI:1.47-2.71,P =0.000;OR =2.37,95 ％ CI:1.31-4.27,P =0.004).Conclusions The SNPs of promoter region of LOXL1 gene are associated with hereditary susceptibility of XFS individually in Uygur population.The SNPs of rs4886467 locus are protective factor,while the SNPs of rs4558370,rs4461027,rs4886761 and rs16958477 locus are risk factors for pathogenesis of XFS.
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Objective To explore the interaction between a serotonin transporter gene promoter region polymorphism(5-HTTPR) and stress in predicting anxiety symptoms.Methods Through random cluster sampling,a total of 252 healthy adolescents participated in this study.During the initial assessment,all participants completed the Adolescent Life Events Questionnaire (ALEQ) and Multidimensional Anxiety Scale for Children (MASC) to assess their levels of stress and anxiety and were genotyped for the 5-HTTLPR polymorphism.Participants subsequently completed MASC and ALEQ once every three months during the subsequent 24 months.A multilevel model was used to investigate the interaction between 5-HTTLPR and stress that predict anxiety symptoms.Results The results indicated no major effect of 5-HTTLPR in males (β=0.80,P＞0.05)or females(β=-0.21,P＞0.05).There were major effects of stress in males(β=0.30,P＜0.01) and females (β=0.33,P＜0.01)and a significant interaction between 5-HTTLPR and stress.Females with at least one 5-HTTLPR S allele(β=0.11,P＜ 0.01)and males with at least one 5-HTTLPR L allele(β=-0.10,P＜0.01)exhibited more anxiety symptoms under stressful situations.Conclusion The interaction between 5-HTTLPR and stress can predict anxiety symptoms in adolescents.There are gender differences on the 5-HTTLPR × stress interaction.
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Objective To predict the functions of hsa-miR-1908 promoter using various bioinformatic tools, and to provide clues for further study on transcriptional regulation mechanism of miR-1908 in human adipocytes. Methods The promoter se-quence of miR-1908 was obtained from Ensemble, and then the CpG islands and transcription factor binding sites were pre-dicted by a variety of online bioinformatic tools. Results The length of the miR-1908 promoter sequence was 1 458 bp. The CpG islands, which inhibited the transcription of miR-1908, were located at (438-756) bp, (836-937) bp and (979-1374) bp. Meanwhile, 15 transcription factor binding sites were found in the promoter sequence of miR-1908. Conclusions miRNA up-stream promoter related bioinformatics can not only improve the efficiency of microRNA promoter research, but also provide further important information on transcriptional regulation of miR-1908.
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AKT is a signal transduction protein that plays a central role in the tumorigenesis. There are 3 mammalian isoforms of this serine/threonine protein kinase-AKT1, AKT2, and AKT3-showing a broad tissue distribution. We first discovered 2 novel polymorphisms (AKT2 -9826 C/G and AKT3 -811 A/G), and we confirmed 6 known polymorphisms (AKT2 -9473 C/T, AKT2 -9151 C/T, AKT2 -9025 C/T, AKT2 -8618G/A, AKT3 -675 A/-, and AKT3 -244 C/T) of the AKT2 and AKT3 promoter region in 24 blood samples of Korean lung cancer patients using direct sequencing. To evaluate the role of AKT2 and AKT3 polymorphisms in the risk of Korean lung cancer, genotypes of the AKT2 and AKT3 polymorphisms (AKT2 -9826 C/G, AKT2 -9473 C/T, AKT2 -9151 C/T, AKT2 -9025 C/T, AKT2 -8618G/A, and AKT3 -675 A/-) were determined in 360 lung cancer patients and 360 normal controls. Statistical analyses revealed that the genotypes and haplotypes in the AKT2 and AKT3 promoter regions were not significantly associated with the risk of lung cancer in the Korean population. These results suggest that polymorphisms of the AKT2 and AKT3 promoter regions do not contribute to the genetic susceptibility to lung cancer in the Korean population.
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Humans , Cell Transformation, Neoplastic , Genetic Predisposition to Disease , Genotype , Haplotypes , Lung , Lung Neoplasms , Polymorphism, Genetic , Promoter Regions, Genetic , Protein Isoforms , Signal Transduction , Tissue DistributionABSTRACT
To investigate whether there is mutation in DC-SIGN promoter region in patients with chronic hepatitis B (CHB) and healthy persons previously infected with hepatitis B virus (HBV) and to explore the relationship between the mutation in dendritic cell-specific intercellular adhension molecule-3-grabbing nonintegrin (DC-SIGN) promoter region and HBV.Methods The studied population was composed of two cohorts:47 CHB patients and 20 healthy persons previously infected with HBV.The mutation in DC-SIGN promoter region was detected with PCR,single-stranded conformational polymorphism and heteroduplex analysis,cloning,sequencing and aligning the published DC-SIGN promoter sequence.Results The characteristic mutation within DCSIGN promoter region in HBV infected individuals was observed.In the DC-SIGN promoter region,4 hot spot mutations located in positions - 139,- 142,- 222,and - 336 were observed in the CHB patients,but only 1 spot mutation located in position - 139 was observed in the healthy persons previously infected with HBV.The -336C which was absent in the healthy persons previously infected with HBV was shown in 11 CHB patients (23.40％).The - 139T was far more frequent in the healthy persons previously infected with HBV ( 100％ ) than in the CHB patients (34.04％).Conclusion In the DC-SIGN promoter region,-336C may be a genetic risk factor for developing CHB,but -139T may be associated with protection against HBV.
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Objective To explore the association between the 5-HTR2A (-1438A/G)promoter region gene polymorphisms and unipolar depression and effcacy of antidepressant drugs in northwest Chinese Han population.Methods Polymerase chain reaction (PCR) was used to detect the distributive frequency of serotonin 2A receptor promoter region polymorphisms of 136 unipolar depression patients( patient group) and 160 normal people tween the patient group and the control group.The frequency of AG,GG genotypes; and G allele in patients was phisms of 5-HT2AR promoter region were correlated with SSRIs treatment response(F= 6.317, P= 0.013 ).There was significant difference of the effective power at the end of week 2 ( x2 = 5.878, P= 0.015 ).The effective power of AA, AG genotype was much higher than that of GG genotype and the effective power in the group with AA genotype was higher than that with AG genotype( each 87.8% ,57.6% ,53.7% ).Conclusion The frequency of GG genotype of 5-HTR2A( 1348A/G)may be associated with episode of unipolar depression in northwest Chinese Han population and A allele may be correlated with well response to paroxetine.
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Objective To detect the single nucleotide polymorphisms (SNPs) in the upstream promoter region of chemokine like factor (CKLF) gene and analyze their possible associations with asthma and asthma-related phenotypes.Methods Direct Sequence of the 1553bp upstream promoter region of CKLF gene was performed in 245 Chinese Han human genomic DNAs (119 asthmatics and 126 controls).The frequencies of alleles, genotypes, and haplotypes were determined and the association of these SNPs with asthmawere further analyzed.Results Fournovel SNPs,SNP88 (T>C),SNPI96 (T>C),SNP568 (C> G) ,and SNP1047 (C > G) were found in the promoter region of CKLF.The frequency of rare allele was 0.168 (SNP88C), 0.168 (SNP196C), 0.352 (SNP568G) and 0.167 (SNP1047G), respectively.Haplotypes,their frequencies and the linkage disequilibrium coefficients between SNPs were constructed.Complete linkage disequilibrium (LDs) were observed between SNP88 and SNP196,SNP88 and SNP1047, as well as SNPI96 and SNP1047 ,respectively (D1 = 1.000,r2 = 1.000).SNP568 was in partial LD with the other three SNPs (r2 = 0.366).No association between asthma and the SNPs was observed.Conclusions Four SNPs in the regulatory region of CKLF in Chinese Han population were firstly identified.Although no significant correlation with asthma was revealed, the SNP and haplotype information is useful for other disease association studies in the future.
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The inactivation of tumour suppressor genes by aberrant methylation of promoter regions has been described as a frequent event in neoplasia development, including lung cancer. The p16 gene is a tumour suppressor gene involved in the regulation of cell cycle progression that has been reported to be inactivated by promoter methylation in lung carcinomas at variable frequencies around the world in a smoking habit dependent manner. The purpose of this study was to investigate the methylation status of the promoter region of the p16 gene in 74 non-small cell lung carcinomas from Chile. The frequency of p16 gene inactivation by promoter methylation was determined as 79.7 percent (59/74). When we considered histological type, we observed that p16 promoter methylation was significantly higher in squamous cell carcinomas (30/33, 91 percent) compared with adenocarcinomas (21/30, 70 percent) (p=0.029). In addition, no association between p16 promoter methylation and gender, age or smoking habit was found (p=0.202, 0.202 and 0.147 respectively). Our results suggest that p16 promoter hypermethylation is a very frequent event in non-small cell lung carcinomas from Chile and could be smoking habit-independent.
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Aged , Female , Humans , Male , Carcinoma, Non-Small-Cell Lung/genetics , DNA Methylation/drug effects , Lung Neoplasms/genetics , Promoter Regions, Genetic , Smoking/adverse effects , Chile , Carcinoma, Non-Small-Cell Lung/etiology , Lung Neoplasms/etiology , Polymerase Chain ReactionABSTRACT
Objective To explore the association between three SNPs of IL 10 promoter and childhood systemic lupus erythematosus (SLE).Methods Three SNPs( 1082/ 819/ 592) were genotypes,and evidence for linkage disequilibrium was analyzed using Genehunter 2 0 software.The correlations between symptoms and haplotypes were assessed.Results The results showed that all genotypes and haplotypes in the IL 10 promoter region exhibited to significant association with childhood SLE,and no significant differences in clinical features among childhood SLE with various haplotypes could be demonstrated.But the frequence of haplotype GCC ( 1082 *G 819 *C 592 *C) in children with SLE and their parents was higher than that in adult SLE patients and adult normal controls,and the frequence of ATA in children with SLE was lower than that of adult SLE patients.Conclusion It is concluded that haplotype GCC might have certain relationship with childhood SLE,which deserves further study.
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Human leukocyte antigen (HLA) class II molecules are polymorphic cell surface glycoproteins that are crucial for the cellular interaction in immune response. The expression of class II molecules is regulated in a tissue-specific and cytokine-inducible manner, and is mainly restricted to the antigen presenting cells. However, some tumor cells also express class II molecules, and in some class-II-negative tumor cells, class II expression is inducible by interferon (IFN)-gamma. However, their expression varies, even though the tumor cells originate from the same histological origin; some tumor cells show strong expression, others show weak or no expression. To determine whether this differential expression of class II molecules on tumor cells is transcriptionally regulated, FACS analysis and Northern hybridization were performed using a panel of melanoma cell lines, IGR3, Malme-3M, SK-Mel-24, and SK-Mel-28 to analyze the cell surface expression and mRNA transcription rate of HLA-DR before and after treatment with IFN-gamma. FACS analysis showed that before IFN-gamma treatment, IGR3 and Malme-3M cells barely expressed HLA-DR. On the contrary, almost all of the SK-Mel-24 cells (> 90%) and a relatively high rate (> 50%) of SK-Mel-28 cells expressed HLA-DR. After IFN-gamma treatment, HLA-DR expression was induced in Malme-3M cells and SK-Mel-28 cells which displayed elevated levels of HLA-DR expression in a time-dependent manner. However, IGR3 cells never responded to IFN-gamma. Northern analysis showed that treatment with IFN-gamma led to the steady-state mRNA augmentation of the HLA-DR gene in Malme-3M and SK-Mel-28, whereas in IGR3, IFN-gamma did not augment the transcriptional rate of the HLA-DR gene. To further clarify this differential modulation, sequencing analysis of PCR product of the HLA-DR proximal promoter region was done, since the transcription rate of the class II gene is controlled by the well-conserved proximal promoter region. Six independent clones from PCR products of the HLA-DRA proximal promoter region and 16 clones from PCR products of the HLA-DRB proximal promoter region were isolated from the above cell lines and sequenced. Comparison of the nucleotide sequences of all 6 clones of DRA promoter showed that the sequences are extremely similar in both regulatory sequences and their intervening sequences. Sixteen clones of HLA-DRB promoter showed sequence variations such as substitution and insertion/deletion, and these 16 clones could be further grouped into 6 homologues with sequence homology. These data established that the melanoma cell lines studied here showed a differential susceptibility to IFN-gamma on the modulation of HLA-DR molecules, that this modulation is transcriptionally regulated, and that the difference in promoter activity by sequence variation might contribute to such a differential transcriptional regulation at the promoter level.
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Humans , Base Sequence , Gene Expression Regulation, Neoplastic/drug effects , HLA-DR Antigens/genetics , Interferon-gamma/pharmacology , Melanoma/genetics , Molecular Sequence Data , Polymerase Chain Reaction , Promoter Regions, Genetic , RNA, Messenger/analysis , Tumor Cells, CulturedABSTRACT
Duchenne Muscular Dystrophy (DMD) gene analysis for 25 unrelated patients from Western India using PCR screening for 14 exons and the promoter region was carried out. Intragenic deletions were detected in 18 patients and most of them were located at the 3' hot spot region of the gene indicating that this part of the gene is more deletion prone in the Indian population from Western India as well. The frequency of deletions observed in the present study is 72%.