Dissertation > Excellent graduate degree dissertation topics show

Association of Decorin Proximal Promoter and 5’-UTR Methylation Status with Non-small Cell Lung Cancer

Author: QianQian
Tutor: ZhangHongTao
School: Suzhou University
Course: Genetics
Keywords: Methylation Decorin gene NSCLC Gene expression
CLC: R734.2
Type: Master's thesis
Year: 2011
Downloads: 22
Quote: 0
Read: Download Dissertation

Abstract


Background and Objective: Lung cancer, including non-small cell lung cancer (NSCLC) and SCLC, is a leading cause of cancer death worldwide. DNA methylation has been considered to correlate with lung cancer, playing an important role in the development and progression of lung cancer. This study aims to investigate the association of Decorin gene proximal promoter region and 5’-UTR region methylation status with mRNA and protein expression in normal bronchial epithelial cell line and NSCLC cell lines, providing a theoretical basis for early diagnosis, prognosis and treatment of NSCLC.Methods: A PCR with universal primers and cloning sequencing were performed in three cell lines (Normal bronchial epithelial cell line HBE, Low metastatic giant-cell lung cancer cell line 95C, High metastatic giant-cell lung cancer cell line 95D) and three stage IV NSCLC tissues and paired corresponding paracancerous lung tissues to examine CpG sites methylation status of the proximal promoter region and 5’-UTR region of Decorin gene, then calculate the methylation frequencies of CpG sites located in the transcription factor (TF) binding sites. Meanwhile, fluorescent real-time quantitative PCR was carried out to analyze the mRNA level of Decorin gene in three cell lines. In addition, Enzyme-linked immunosorbent assay (ELISA) was applied to determine the Decorin protein level in three cell lines.Results: There are twenty CpG sites located in the proximal promoter region and 5’-UTR region of Decorin gene. According to Transcription Factor Binding Site Prediction software, we found that four CpG sites were located in the TF binding sites, which existed upstream from the transcription initial of Decorin, including -447bp, -391bp, -201bp and +58bp, and the corresponding TF were Oct-1, CDP CR, GATA-1, AhR-Ar individually. The sequencing results showed that the methylation frequencies of CpG sites located in CDP CR and AhR-Ar binding sites were 40%, 5%, 0% and 40%, 65%, 95% in three cell lines respectively. Statistical analysis showed that these two CpG sites methylation frequencies have significant difference among three cell lines (P<0.01). In addition, we detected these two CpG sites methylation frequencies in cancer and paired paracancerous lung tissues. The methylation frequencies of CpG sites which located in CDP CR binding sites were higher in paired paracancerous lung tissues than in cancer tissues, the situation of the methylation frequencies of CpG sites which located in AhR-Ar binding sites were opposite.The Real-time PCR results suggested the reduction of Decorin mRNA level was observed in three cell lines, and mRNA relative expression of Decorin gene had significant difference in three cell lines (P<0.05). The ELISA results showed that the reduction of Decorin protein expression in three cell lines were consistent with the mRNA expression of Decorin gene, and Decorin protein expression had significant difference in three cell lines (P<0.001).Conclusion: We discovered the methylation frequencies of CpG sites of Decorin gene proximal promoter region and 5’-UTR region, which CpG sites located in CDP CR and AhR-Ar binding sites, had significant difference in three cell lines. The fact that mRNA level expression of Decorin gene was reduced in three cell lines, it suggested the decrease of CpG methylation frequencies of CDP CR binding sites (CDP CR acts as a repressor in transcriptional regulation) and increase of CpG methylation frequencies of AhR-Ar bind sites (AhR-Ar acts as an activator in transcriptional regulation) may prevent the transcription of Decorin gene synergistically. Our results indicated that there was significant association between the methylation status of the proximal promoter region and 5’-UTR region of Decorin gene with its mRNA expression, providing new target for NSCLC clinical early diagnosis and new anti-tumor drug development.

Related Dissertations

  1. Research on Combinatorial Regulation of Multiple Transcription Factors,Q78
  2. The Expression Survey of BMP Signalling Pathway in the Human Embryonic Tooth Germ,R78
  3. Study on Synthesis and Physiological Function of N-carbamoyl-glutamate,R914
  4. Functional Analysis of Two Rice Nitrate Transporter Genes OsNRT1.1a and OsNRT1.1b,S511
  5. Coparative Analyses of Carbon and Nitrogen Metabolism of Flue-cured Tobacco Growing in Henan and Yunnan,S572
  6. Study of Chicken Δ~6 Fatty Acid Desaturase Gene’s Promotor Region Polymorphism and Gene Expression,S831
  7. The Expression of CPV-2 VP2 Gene in SF9 and Development of Indirect Elisa for Serum Antibodys,S852.65
  8. Comparison of Gene Expression Data Cluster Methods and Gene Network Construction for Phytophthora Sojae Genes,S435.651
  9. Functional Identification of Two Tomoto Phosphater Transporter Genes LePT1 and LePT2 in Rice,S511
  10. Analysis for Intron 1 and 2 of Rice Transformation to Promoter Activity,S511
  11. Research on Characteristics of Growth, Development and Material Metabolism of Flue Cured Tobacco Leaves in Huili, Sichuan,S572
  12. Studies on Extracting Mitochondrial DNA and Gene Expressions in Brassica Napus L,S565.4
  13. Functional Characterization of Wheat Na~+ /H~+ Antiporter TaNHX2 and Study of TaNHX2 C- Terminus Domain,S512.1
  14. Identification and Analysis of miRNA and Flower Development Specific Genes in Wheat,S512.1
  15. Studies on the Mechanism and Recovery Measures of Hyperhydricity of Pyrus Calleryana Decne in Vitro,S661.2
  16. Molecular Characterization, Expression, and Promoter Methylation Status of the Bovine Synaptonemal Complex Protein 3 Gene,S823
  17. The Deposition Rule and Gene Expression Involved in Yolk Cholesterol in Different Layer Breeds,S831
  18. Study on the mRNA Expression Level and the Polymorphism of Follicle-Stimulating Hormone Receptor Gene in Taihu Pig’s Ovary,S828
  19. The Effects of Don on Proliferation, Differentiation, and Apoptosis of Chondrocytes in Chicken,S858.31
  20. Effects of 5-Aza-2-deoxycytidine on DNA Methylation and Expression of p16 and MGMT Gene in Lung Cancer Cell Line SPC-A-1,R734.2
  21. Methylation of p16 Gene in Plasma and Tissues from Non-small Cell Lung Cancer Patients, Demethylation and the Biological Behavior of Lung Cancer Cell and Transcription of p16 Gene,R734.2

CLC: > Medicine, health > Oncology > Respiratory system tumors > Lung tumors
© 2012 www.DissertationTopic.Net  Mobile