Unknown,Transcriptomics,Genomics,Proteomics

Dataset Information

Gastric cancers of Western European and African patients

ABSTRACT: Gastric cancer is the second most common cause of cancer death worldwide, but incidence and mortality rates show large variations across different countries. Variation in risk factors between different populations, including environmental and host factors influencing gastric cancer risk, have been reported but little is known about the biological differences between gastric cancers from different geographic locations. We set out to study genomic instability patterns of gastric cancers obtained from patients from United Kingdom (UK) and South Africa (SA). DNA was isolated from 67 gastric adenocarcinomas, 33 UK patients, 9 Caucasian SA patients and 25 native SA patients. Microsatellite instability and chromosomal instability were analyzed by PCR and microarray comparative genomic hybridization, respectively. Data was analyzed by supervised univariate and multivariate analyses as well as unsupervised hierarchical cluster analysis. Tumors from Caucasian and native SA patients showed significantly more microsatellite instable tumors (p<0.05). For the microsatellite stable tumors, geographical origin of the patients correlated with cluster membership, derived from unsupervised hierarchical cluster analysis (p=0.001). Several chromosomal alterations showed significantly different frequencies in tumors from UK patients and native SA patients, but not between UK patients and Caucasian SA patients and between native and Caucasian SA patients. In conclusion, gastric cancers from South African and UK patients show differences in genetic instability patterns, indicating possible different biological mechanisms underlying the disease. 67 gastric adenocarcinomas, 33 UK patients, 9 Caucasian SA patients and 25 native SA patients.

ORGANISM(S): Homo sapiens

SUBMITTER: Oscar Krijgsman

PROVIDER: E-GEOD-22789 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Gastric cancers of Western European and African patients show different patterns of genomic instability.

Buffart Tineke E TE Louw Melanie M van Grieken Nicole C T NC Tijssen Marianne M Carvalho Beatriz B Ylstra Bauke B Grabsch Heike H Mulder Chris J J CJ van de Velde Cornelis J H CJ van der Merwe Schalk W SW Meijer Gerrit A GA

BMC medical genomics 20110113

<h4>Background</h4>Infection with H. pylori is important in the etiology of gastric cancer. Gastric cancer is infrequent in Africa, despite high frequencies of H. pylori infection, referred to as the African enigma. Variation in environmental and host factors influencing gastric cancer risk between different populations have been reported but little is known about the biological differences between gastric cancers from different geographic locations. We aim to study genomic instability patterns ...[more]

PMID: 21226972

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Dataset Information

Gastric cancers of Western European and African patients

Publications

Gastric cancers of Western European and African patients show different patterns of genomic instability.

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