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Subtractive Hybridization Technique (subtractive + hybridization_technique)
Selected AbstractsIdentification of some human genes oppositely regulated during esophageal squamous cell carcinoma formation and human embryonic esophagus developmentDISEASES OF THE ESOPHAGUS, Issue 3 2010M. V. Zinovyeva SUMMARY Here we directly compared gene expression profiles in human esophageal squamous cell carcinomas and in human fetal esophagus development. We used the suppression subtractive hybridization technique to subtract cDNAs prepared from tumor and normal human esophageal samples. cDNA sequencing and reverse transcription polymerase chain reaction (RT-PCR) analysis of RNAs from human tumor and the normal esophagus revealed 10 differentially transcribed genes: CSTA, CRNN, CEACAM1, MAL, EMP1, ECRG2, and SPRR downregulated, and PLAUR, SFRP4, and secreted protein that is acidic and rich in cysteine upregulated in tumor tissue as compared with surrounding normal tissue. In turn, genes up- and downregulated in tumor tissue were down- and upregulated, respectively, during development from the fetal to adult esophagus. Thus, we demonstrated that, as reported for other tumors, gene transcriptional activation and/or suppression events in esophageal tumor progression were opposite to those observed during development from the fetal to adult esophagus. This tumor ,embryonization' supports the idea that stem or progenitor cells are implicated in esophageal cancer emergence. [source] Identification of the genes associated with a virulent strain of Porphyromonas gingivalis using the subtractive hybridization techniqueMOLECULAR ORAL MICROBIOLOGY, Issue 1 2008M. Tachibana-Ono Background/aims:,Porphyromonas gingivalis, a major etiological organism implicated in periodontal disease, can be classified into virulent and avirulent strains. Our aim was to identify a gene for the virulence of P. gingivalis. Methods:, The subtractive hybridization technique was employed to identify the genes specific to P. gingivalis W83, a virulent strain. In this study, P. gingivalis W83 was used as the tester strain, and P. gingivalis ATCC 33277 was the driver strain. The prevalence of W83-specific genes was determined by Southern blot analysis of several P. gingivalis strains. Results:, We obtained 575 colonies using the subtractive hybridization technique. From among these, 26 DNA fragments were subjected to a homology search using the BLAST program. Compared with strain ATCC 33277, strain W83 contained 12 unique clones. The specificities of the isolated DNA fragments were analyzed among four P. gingivalis strains by Southern blot analysis. Five genes showed specificity for strain W83 compared with strain ATCC 33277. All five genes were also identified in strain W50. Conclusions:, The subtractive hybridization technique was effective in screening the two strains for specific DNA sequences, some of which might be responsible for determining virulence. The results suggested that several genes specific to strain W83 were associated with its virulence. Further analysis of these DNA fragments will provide important information on the pathogenesis of virulent P. gingivalis strains. [source] Down-regulation of cathepsin K in synovium leads to progression of osteoarthritis in rabbitsARTHRITIS & RHEUMATISM, Issue 8 2009Daisuke Takahashi Objective The hypothesis of this study was that synovial factors playing a pivotal role in the pathogenesis of osteoarthritis (OA) and thus gene expression in the synovium would be altered at the initial stage of OA. The aims of this study were to identify the candidate genes in synovium related to OA initiation, to evaluate cartilage degeneration after knockdown of the gene using small interfering RNA (siRNA) gene silencing in the knee joints at the initial stage of OA, and to determine the potential role of the knocked-down gene in OA initiation. Methods Genes overexpressed in synovium at the initial stage of disease in a rabbit model of anterior cruciate ligament transection (ACLT),induced OA were identified using the suppression subtractive hybridization technique and differential screening. Candidate gene expression in the synovium of the knees of rabbits with OA was manipulated with electroporation-assisted siRNA transduction 4 times before and after operation. Four weeks after surgery, histologic analysis was performed. Results Cathepsin K gene and protein expression was significantly up-regulated in synovium at the initial stage of OA in rabbits. Down-regulation of cathepsin K in synovium at the initial stage of OA significantly accelerated cartilage degeneration. Conclusion These results indicate that cathepsin K plays a protective role in cartilage degeneration at the initial stage of OA. We believe that the current results obtained from models of the early phase of OA will provide useful information for developing a novel strategy to prevent disease progression. [source] | ||||||||||