AIM: To investigate the mutations of the 5' noncoding region of BCL-6 gene in Chinese patients with primary gastric lymphomas. METHODS: PCR and direct DNA sequencing were used to identify BCL-6 gene mutations in t...AIM: To investigate the mutations of the 5' noncoding region of BCL-6 gene in Chinese patients with primary gastric lymphomas. METHODS: PCR and direct DNA sequencing were used to identify BCL-6 gene mutations in the 5' noncoding region in 29 cases of gastric diffuse large B-cell lymphoma (DLBCL) and 18 cases of gastric mucosa-associated lymphoid tissue (MALT) lymphoma as well as 10 cases of reactive hyperplasia of lymph node (LRH). RESULTS: Six of 29 gastric DLBCLs (20.7%), 4 of 18 gastric MALT lymphomas (22.2%) and 1 of 10 LRHs(10%) were found to have mutations. All mutations were single-base substitutions and the frequency of single-base changes was 0.20×1O^(-2)-1.02×1O^(-2)per bp. CONCLUSION: Point mutations in the 5' noncoding region of BCL-6 gene are found in Chinese patients with primary gastric DLBCLs and MALT lymphomas, suggesting that they may, in some extent, participate in the pathogenesis of primary gastric DLBCLs and MALT lymphomas.展开更多
ObjectiveTo investigate BCL 6 gene mutations in Chinese populations with B cell non Hodgkin's lymphoma Methods Polymerase chain reaction (PCR), denaturing gradient gel electrophoresis (DGGE) and direct D...ObjectiveTo investigate BCL 6 gene mutations in Chinese populations with B cell non Hodgkin's lymphoma Methods Polymerase chain reaction (PCR), denaturing gradient gel electrophoresis (DGGE) and direct DNA sequencing were used to identify mutations in the 5' noncoding region of the BCL 6 gene in a total of 40 cases of diffuse large cell lymphoma (DLCL) and follicular lymphoma (FL) Results Nine cases were found to have base substitutions The incidence of BCL 6 gene mutation and the frequency of single base changes were approximately 25 7% and (0 56-1 10)×10 2 /bp, respectively Conclusions The 5' regulatory region of the BCL 6 gene undergoes frequent somatic hypermutation during lymphomagenesis and the identification of BCL 6 gene hypermutations provides a molecular marker for confirmatory diagnosis of B NHL展开更多
Objective: This study aimed to investigate DNA sequences that are substantially homologous to the corresponding RNA sequence sections of the hepatitis C virus (HCV). These DNA sequences are present in the whole DNA ex...Objective: This study aimed to investigate DNA sequences that are substantially homologous to the corresponding RNA sequence sections of the hepatitis C virus (HCV). These DNA sequences are present in the whole DNA extracted from peripheral blood mononuclear cells (PBMCs) of HCV-negative subjects. We presumed that these experimentally proven 5'-noncoding region (5'-NCR) homologous DNA sequences could be contained in the extrachromosomal circular DNA (eccDNA) fraction as part of the whole cellular DNA. Methods: Home-made polymerase chain reaction (PCR) with whole cellular and isolated eccDNA, nucleotide basic local alignment search tool (BLASTn) alignments, and tests for patterns of methylation in selected sequence sections were performed. Results: The PCR tests revealed DNA sequences of up to 320 bp that broadly matched the corresponding sequence sections of known HCV genotypes. In contrast, BLASTn alignment searches of published HCV 5'-NCR sequences with human genome databases revealed only sequence segments of up to 36 bp of the 5'-NCR. The composition of these sequences shows missing base pairs, base pair mismatches as well as complete homology with HCV reference sequences. These short sequence sections are present in numerous copies on both the same and different chromosomes. The selected sequence region within the DNA sequences of the 5'-NCR revealed a broad diversity of individual patterns of methylation. Conclusions: The experimental results confirm our assumption that parts of the HCV 5'-NCR genomic RNA sequences are present at the DNA level in the eccDNA fraction of PBMCs. The tests for methylation patterns therein revealed individual methylomes which could represent an epigenetic feature. The respective sequence section might be subject to genetic regulation.展开更多
基金Supported by National Natural Science Foundation of China,No.39900065
文摘AIM: To investigate the mutations of the 5' noncoding region of BCL-6 gene in Chinese patients with primary gastric lymphomas. METHODS: PCR and direct DNA sequencing were used to identify BCL-6 gene mutations in the 5' noncoding region in 29 cases of gastric diffuse large B-cell lymphoma (DLBCL) and 18 cases of gastric mucosa-associated lymphoid tissue (MALT) lymphoma as well as 10 cases of reactive hyperplasia of lymph node (LRH). RESULTS: Six of 29 gastric DLBCLs (20.7%), 4 of 18 gastric MALT lymphomas (22.2%) and 1 of 10 LRHs(10%) were found to have mutations. All mutations were single-base substitutions and the frequency of single-base changes was 0.20×1O^(-2)-1.02×1O^(-2)per bp. CONCLUSION: Point mutations in the 5' noncoding region of BCL-6 gene are found in Chinese patients with primary gastric DLBCLs and MALT lymphomas, suggesting that they may, in some extent, participate in the pathogenesis of primary gastric DLBCLs and MALT lymphomas.
基金ThisworkwassupportedbythegrantsfromtheNationalNaturalScienceFoundationofChina (No 3 9770 83 0 ) andDr ClydeFoundation
文摘ObjectiveTo investigate BCL 6 gene mutations in Chinese populations with B cell non Hodgkin's lymphoma Methods Polymerase chain reaction (PCR), denaturing gradient gel electrophoresis (DGGE) and direct DNA sequencing were used to identify mutations in the 5' noncoding region of the BCL 6 gene in a total of 40 cases of diffuse large cell lymphoma (DLCL) and follicular lymphoma (FL) Results Nine cases were found to have base substitutions The incidence of BCL 6 gene mutation and the frequency of single base changes were approximately 25 7% and (0 56-1 10)×10 2 /bp, respectively Conclusions The 5' regulatory region of the BCL 6 gene undergoes frequent somatic hypermutation during lymphomagenesis and the identification of BCL 6 gene hypermutations provides a molecular marker for confirmatory diagnosis of B NHL
基金Project supported by the Exchange Scholarship Programs of the Landesregierung Schleswig-Holstein,Germany,for Jian-er WO
文摘Objective: This study aimed to investigate DNA sequences that are substantially homologous to the corresponding RNA sequence sections of the hepatitis C virus (HCV). These DNA sequences are present in the whole DNA extracted from peripheral blood mononuclear cells (PBMCs) of HCV-negative subjects. We presumed that these experimentally proven 5'-noncoding region (5'-NCR) homologous DNA sequences could be contained in the extrachromosomal circular DNA (eccDNA) fraction as part of the whole cellular DNA. Methods: Home-made polymerase chain reaction (PCR) with whole cellular and isolated eccDNA, nucleotide basic local alignment search tool (BLASTn) alignments, and tests for patterns of methylation in selected sequence sections were performed. Results: The PCR tests revealed DNA sequences of up to 320 bp that broadly matched the corresponding sequence sections of known HCV genotypes. In contrast, BLASTn alignment searches of published HCV 5'-NCR sequences with human genome databases revealed only sequence segments of up to 36 bp of the 5'-NCR. The composition of these sequences shows missing base pairs, base pair mismatches as well as complete homology with HCV reference sequences. These short sequence sections are present in numerous copies on both the same and different chromosomes. The selected sequence region within the DNA sequences of the 5'-NCR revealed a broad diversity of individual patterns of methylation. Conclusions: The experimental results confirm our assumption that parts of the HCV 5'-NCR genomic RNA sequences are present at the DNA level in the eccDNA fraction of PBMCs. The tests for methylation patterns therein revealed individual methylomes which could represent an epigenetic feature. The respective sequence section might be subject to genetic regulation.
