No abstract available.
DNA, Neoplasm/genetics ; High-Throughput Nucleotide Sequencing/*methods ; Humans ; Sequence Analysis, DNA/methods ; Urologic Neoplasms/*genetics

No abstract availble.
DNA Mutational Analysis ; Humans ; *Microsatellite Instability ; Neoplasm Staging ; Prognosis ; Stomach Neoplasms/*diagnosis/genetics/surgery

BACKGROUND/AIMS: The fragile histidine triad (FHIT) gene located at chromosome 3p14.2, is a candidate tumor suppressor gene often involved in various tumors. Homozygous deletions, lack or reduced expression of FHIT protein, and alteration of its transcription were frequently observed in several types of primary human cancers and cell lines. In the present study, we examined the expression profiles of aberrant FHIT transcripts to explore the role of FHIT gene in gastric carcinogenesis. METHODS: In 6 gastric cancer cell lines, nested reverse transcription-polymerase chain reaction (RT-PCR) and cDNA sequence analyses were performed to detect and characterize the aberrant FHIT transcripts. RESULTS: In addition to the wild-type FHIT transcript, small-sized transcripts with various numbers and lengths were observed in all of the cell lines examined. cDNA sequence analysis confirmed that different types of truncated transcripts included exonic deletions, insertions of intron 5 sequences between exons, and combinations of both. Most of these transcripts lacked exon 5 in which translation initiation codon is located. Aberrant transcripts with partial exonic deletions due to activation of cryptic splice sites were also observed in 5 cell lines. Additionally, multi-step splice patterns indicative of additional downstream processing, were observed in several cancer lines. CONCLUSIONS: These results suggest that the aberrant FHIT transcripts in gastric cancer cell lines results from faulty splicing, including exon skipping, selection of cryptic splice site, and additional downstream splice processing.
*Acid Anhydride Hydrolases ; Cell Line, Tumor ; Codon, Initiator/genetics ; DNA, Complementary/genetics ; Genes, Tumor Suppressor ; Humans ; Neoplasm Proteins/*genetics ; *Sequence Analysis, DNA ; Stomach Neoplasms/*genetics ; *Transcription, Genetic

Mutation of the p53 tumor suppressor gene has been related in the pathogenesis of numerous human and canine cancers, including breast cancers and mammary tumors. We have investigated exons 5-8 of the p53 gene for mutations in 20 spontaneous canine mammary tumors using polymerase chain reaction (PCR) with direct sequence analysis to evaluate the role of this gene in canine mammary tumorigenesis and analyzed to compare with other clinicopathological parameters including age, histology, stage, recurrence and death from tumor. Four missense (one case had two missense mutations) and one nonsense mutations were detected in 10 malignant lesions (40%), and two missense and one silent mutations were found in 10 benign mammary tumors (30%). Five of the missense mutations were located in highly conserved domains II, III, IV and V. After a follow-up period, four dogs showed a progression and three of these patients revealed death from mammary carcinoma with p53 mutation. These results demonstrated that the p53 gene mutations might be involved in the development of canine mammary tumors and contribute to the prognostic status in canine mammary carcinomas.
Animals ; Codon, Nonsense/genetics ; DNA, Neoplasm/chemistry/genetics ; Dog Diseases/*genetics ; Dogs ; Female ; Genes, p53/*genetics ; Mammary Neoplasms, Animal/*genetics ; Mutation, Missense/genetics ; Polymerase Chain Reaction/veterinary ; Sequence Analysis, DNA ; Survival Analysis ; Tumor Suppressor Protein p53/genetics

OBJECTIVEEstablishment of a gene expression profile associated with differentiation inducing the glioma cells was made possible.

METHODThe expression level of 18 000 genes in glioma cells was evaluated before and after induction with sodium phenyl-butyrate for 2 hours or 6 days by cDNA array technique, with the results proved by multi-dot blot.

RESULTSNinety-eight gene expressions in the glioma cells were changed after the induction, with some genes in transcription and translation systems down-regulated, some oncogenes down-regulated, and some differentiation or apoptosis genes up-regulated. Eighteen unknown EST fragments were changed also.

CONCLUSIONA gene expression profile associated with differentiation-inducing the glioma cells including 98 genes has been established.

Cell Differentiation ; DNA, Neoplasm ; analysis ; Gene Expression ; Gene Expression Profiling ; Glioma ; genetics ; metabolism ; pathology ; Humans ; Oligonucleotide Array Sequence Analysis ; RNA, Neoplasm ; analysis

This study was purposed to detect single nucleotide polymorphisms (SNP) of 2 pharmacokinetics-related genes in K562 and K562/A02 cell lines. Leukemia cell line K562 and its resistant line K562/A02 were cultured, the genomic DNA was isolated by QIAamp DNA Blood Mini kit, primers were designed, the related DNA fragments were amplified by PCR. The SNP genotyping of mthfr gene rs1801131, rs1801133 and rs2274976 and dpyd gene rs1801159, rs1801160 and rs17376848 was performed by means of matrix assisted laser desorption ionization-time of flight mass spectrometry method (MALDI-TOFMS). The results showed that the genotype of mthfr gene locus 1801131 was AC, rs1801133 was CC, rs2274976 was GG, genotype of dpyd gene locus 1801159 was GG, rs1801160 was GG, rs17376848 was AA in both K562 and K562/A02 cell lines. It is concluded that the above-mentioned loci of mthfr and dpyd genes in K562 and K562/A02 cell lines are not expressed differently.
DNA Mutational Analysis ; DNA Primers ; Dihydrouracil Dehydrogenase (NADP) ; genetics ; Drug Resistance, Multiple ; genetics ; Drug Resistance, Neoplasm ; Genotype ; Humans ; K562 Cells ; Methylenetetrahydrofolate Reductase (NADPH2) ; genetics ; Polymorphism, Single Nucleotide

Adult ; Brain Neoplasms ; genetics ; DNA, Neoplasm ; analysis ; Female ; Genome ; Glioblastoma ; genetics ; Humans ; Loss of Heterozygosity ; Microsatellite Repeats ; Neoplasm Recurrence, Local ; genetics ; Polymerase Chain Reaction

OBJECTIVETo study the mechanism of invasion and metastasis in early nasopharyngeal carcinoma (NPC) in relation to E-cadherin promoter methylation and mutation in exon 3 of beta-catenin.

METHODSMethylation of E-cadherin promoter, mutation in exon 3 of beta-catenin and differential expression of beta-catenin in the primary lesion of 21 NPC and the metastatic lymph node of 21 NPC were investigated by DNA Methylation-Specific PCR, direct sequencing and immunohistochemical method.

RESULTSMethylation on E-cadherin promoter was showed in 23.8% (5/21) primary lesions and 61.9% (13/21) metastatic lymph nodes (P < 0.01). Mutation in exon 3 of beta-catenin was showed in 3 of 42 tissues: codon 37 (TCT-->GCT), codon 41 (ACC-->GCC) and codon 47 (AGT-->ACT). However, there was no relation between these mutations and invasion or metastasis (P > 0.05). High beta-catenin expression on the membrane without nuclear expression was observed in 42 tissues (P > 0.05).

CONCLUSION1. In NPC, methylation of promoter is a major cause of down-regulation of E-cadherin which may finally lead to detachment and metastasis of neoplastic cells, 2. Mutation in exon 3 of beta-catenin is a rare event in NPC. It may be an early event in the carcinogenesis of NPC but have no significant role in invasion and metastasis and 3. High expression of beta-catenin, as one of NPC characteristics, is not a key factor for invasion or metastasis.

Adult ; Aged ; Cadherins ; genetics ; DNA Methylation ; Female ; Humans ; Immunohistochemistry ; Male ; Middle Aged ; Mutation ; Nasopharyngeal Neoplasms ; genetics ; pathology ; Neoplasm Invasiveness ; Neoplasm Metastasis ; Promoter Regions, Genetic ; beta Catenin ; analysis ; genetics

OBJECTIVETo study the clinicopathological and molecular genetic characteristics of hereditary nonpolyposis colorectal cancer (HNPCC), to enable the early diagnosis and to evaluate the treatment.

METHODSWe analyzed 12 families of HNPCC from Wenzhou, Zhejiang province, China. Mismatch repair genes hMSH2 and hMLH1 expression and microsatellite instability of tumor tissue were studied using microdissection, microsatellite analysis, immunohistochemical staining and Gene Scan analysis. Direct DNA sequencing of hMSH2 and hMLH1 were performed subsequently.

RESULTSAltogether 32 patients with colorectal cancer were recognized in 12 HNPCC families, with the median age of 45.2 years (75.0% before the age of 50 years). The proximal tumors accounted for 51.1%, while multiple colorectal cancers accounted for 34.4%. Poor differentiation cancers occupied half of the patients (53.1%). And 68.8% of the patients had the tumor of Dukes A and B. Among 12 HNPCC families, 7 cases in 6 HNPCC families developed extracolonic cancer. 13 cases died during follow up of 1 - 23 years. The median survival time was 6.4 years. 19 alive cases followed up from 1 to 28 years. All tumors (9/9) displayed microsatellite instability, with the half losing hMSH2 or hMLH1 expression. In the 5 genetic analyzed kindreds 3 possessed germline mutation. Two of three mutations have not been reported in the worldwide database previously.

CONCLUSIONHNPCC showed distinct clinicopathological characteristics. Microsatellite instability analysis and immunohistochemical staining might be the effective screening methods before direct DNA sequencing for the detection of mutation in mismatch repair genes. It is important to analyze the members of affected families.

Adaptor Proteins, Signal Transducing ; Adult ; Aged ; Carrier Proteins ; China ; Colorectal Neoplasms, Hereditary Nonpolyposis ; genetics ; metabolism ; pathology ; DNA Mutational Analysis ; DNA, Neoplasm ; chemistry ; genetics ; DNA-Binding Proteins ; analysis ; genetics ; Family Health ; Female ; Humans ; Immunohistochemistry ; Male ; Microsatellite Repeats ; genetics ; Middle Aged ; MutL Protein Homolog 1 ; MutS Homolog 2 Protein ; Mutation ; Neoplasm Proteins ; analysis ; genetics ; Nuclear Proteins ; Proto-Oncogene Proteins ; analysis ; genetics

OBJECTIVETo clone differentially expressed cDNA sequences involved in malignant transformation induced by benzo(a)pyrene metabolite dihydroxyepoxy benzo pyrene (BPDE).

METHODThe malignant transformation of human bronchial epithelial cell line 16HBE induced by BPDE in vitro was used as a model for comparing gene expression between the transformed cells and controls. cDNA representational difference analysis (cDNA-RDA) was performed to isolate differentially expressed cDNA fragment in transformed cells. The cDNA fragments were ligated to pGEM-T vector and transformed into JM109 bacteria. The plasmid DNA were sequenced and compared with data in GenBank by BLASTN.

RESULTSFive cDNA sequences were found to be novel ones and were registered in dbest database, which assigned accession numbers in GenBank are BG354691, BG354692, BG354693, BG354694 and BG354695, respectively. Eight of the remaining cDNA sequences showed sequence homology to those previously reported such as ribosomal protein S23, MLN137, ACTN4, transforming growth factor and G protein gene.

CONCLUSIONSThese 13 genes may be involved in BPDE-induced malignant transformation, but their biological characteristics and functions are left to further studies.

Benzopyrenes ; metabolism ; pharmacology ; Carcinogens ; pharmacology ; Cell Transformation, Neoplastic ; chemically induced ; genetics ; Cells, Cultured ; Cloning, Molecular ; DNA, Complementary ; analysis ; drug effects ; DNA, Neoplasm ; analysis ; Gene Expression ; drug effects ; Humans