Project description:Introduction: CHEK2 is a moderate penetrance breast cancer risk gene, whose truncating mutation 1100delC increases the risk about two fold. We pursued to investigate gene copy number aberrations and gene expression profiles that are typical for breast tumors of CHEK2 1100delC mutation carriers. Materials and methods: A total of 126 breast tumor tissue specimens including 32 samples from patients carrying CHEK2 1100delC were studied in array comparative genomic hybridization (aCGH) and gene expression experiments (GEX). After dimensionality reduction with CGHregions R package, CHEK2 1100delC associated regions in the aCGH data were detected by Wilcoxon rank sum test. Linear model was fitted to GEX data with R package limma. Genes whose expression levels were associated with CHEK2 1100delC mutation were detected by Bayesian method. Results: We discovered four lost and three gained CHEK2 1100delC related loci. These include losses of 1p13.3-31.3, 8p21.1-2, 8p23.1-2 and 17p12-13.1 as well as gains of 12q13.11-3, 16p13.3 and 19p13.3. Twenty-eight genes located on these regions showed differential expression between CHEK2 1100delC and other tumors nominating them as candidates for CHEK2 1100delC associated tumor progression drivers. These included CLCA1 on 1p22 as well as CALCOCO1, SBEM and LRP1 on 12q13. Altogether 188 genes were differentially expressed between CHEK2 1100delC and other tumors. Of these, 144 had elevated and 44 lowered expression levels. Our results suggest WNT pathway as a driver of tumorigenesis in breast tumors of CHEK2 1100delC mutation carriers and a role for the olfactory receptor protein family in cancer progression. Differences in the expression of the 188 CHEK2 1100delC associated genes divided breast tumor samples from three independent datasets into two groups that differed in their relapse-free survival time. Conclusions: We have shown that copy number aberrations of certain genomic regions are associated with CHEK2 mutation 1100delC. On these regions we have identified potential drivers of CHEK2 1100delC associated tumorigenesis, whose role in cancer progression is worth investigating. Furthermore, poorer survival related to the CHEK2 1100delC gene expression signature highlights pathways that are likely to have a role in the development of metastatic disease in carriers of CHEK2 1100delC mutation. 78 samples from breast tumors: 13 tumors from CHEK2 1100delC mutation carriers, 65 other tumors
Project description:Abstract Introduction: CHEK2 is a moderate penetrance breast cancer risk gene, whose truncating mutation 1100delC increases the risk about two fold. We pursued to investigate gene copy number aberrations and gene expression profiles that are typical for breast tumors of CHEK2 1100delC mutation carriers. Materials and methods: A total of 126 breast tumor tissue specimens including 32 samples from patients carrying CHEK2 1100delC were studied in array comparative genomic hybridization (aCGH) and gene expression experiments (GEX). After dimensionality reduction with CGHregions R package, CHEK2 1100delC associated regions in the aCGH data were detected by Wilcoxon rank sum test. Linear model was fitted to GEX data with R package limma. Genes whose expression levels were associated with CHEK2 1100delC mutation were detected by Bayesian method. Results: We discovered four lost and three gained CHEK2 1100delC related loci. These include losses of 1p13.3-31.3, 8p21.1-2, 8p23.1-2 and 17p12-13.1 as well as gains of 12q13.11-3, 16p13.3 and 19p13.3. Twenty-eight genes located on these regions showed differential expression between CHEK2 1100delC and other tumors nominating them as candidates for CHEK2 1100delC associated tumor progression drivers. These included CLCA1 on 1p22 as well as CALCOCO1, SBEM and LRP1 on 12q13. Altogether 188 genes were differentially expressed between CHEK2 1100delC and other tumors. Of these, 144 had elevated and 44 lowered expression levels. Our results suggest WNT pathway as a driver of tumorigenesis in breast tumors of CHEK2 1100delC mutation carriers and a role for the olfactory receptor protein family in cancer progression. Differences in the expression of the 188 CHEK2 1100delC associated genes divided breast tumor samples from three independent datasets into two groups that differed in their relapse-free survival time. Conclusions: We have shown that copy number aberrations of certain genomic regions are associated with CHEK2 mutation 1100delC. On these regions we have identified potential drivers of CHEK2 1100delC associated tumorigenesis, whose role in cancer progression is worth investigating. Furthermore, poorer survival related to the CHEK2 1100delC gene expression signature highlights pathways that are likely to have a role in the development of metastatic disease in carriers of CHEK2 1100delC mutation. 79 samples from breast tumors: 22 tumors from CHEK2 1100delC mutation carriers, 57 other tumors Five files attached represent segmented values, copy number calls, gain, loss and normal copy number probabilities.
Project description:Introduction: CHEK2 is a moderate penetrance breast cancer risk gene, whose truncating mutation 1100delC increases the risk about two fold. We pursued to investigate gene copy number aberrations and gene expression profiles that are typical for breast tumors of CHEK2 1100delC mutation carriers. Materials and methods: A total of 126 breast tumor tissue specimens including 32 samples from patients carrying CHEK2 1100delC were studied in array comparative genomic hybridization (aCGH) and gene expression experiments (GEX). After dimensionality reduction with CGHregions R package, CHEK2 1100delC associated regions in the aCGH data were detected by Wilcoxon rank sum test. Linear model was fitted to GEX data with R package limma. Genes whose expression levels were associated with CHEK2 1100delC mutation were detected by Bayesian method. Results: We discovered four lost and three gained CHEK2 1100delC related loci. These include losses of 1p13.3-31.3, 8p21.1-2, 8p23.1-2 and 17p12-13.1 as well as gains of 12q13.11-3, 16p13.3 and 19p13.3. Twenty-eight genes located on these regions showed differential expression between CHEK2 1100delC and other tumors nominating them as candidates for CHEK2 1100delC associated tumor progression drivers. These included CLCA1 on 1p22 as well as CALCOCO1, SBEM and LRP1 on 12q13. Altogether 188 genes were differentially expressed between CHEK2 1100delC and other tumors. Of these, 144 had elevated and 44 lowered expression levels. Our results suggest WNT pathway as a driver of tumorigenesis in breast tumors of CHEK2 1100delC mutation carriers and a role for the olfactory receptor protein family in cancer progression. Differences in the expression of the 188 CHEK2 1100delC associated genes divided breast tumor samples from three independent datasets into two groups that differed in their relapse-free survival time. Conclusions: We have shown that copy number aberrations of certain genomic regions are associated with CHEK2 mutation 1100delC. On these regions we have identified potential drivers of CHEK2 1100delC associated tumorigenesis, whose role in cancer progression is worth investigating. Furthermore, poorer survival related to the CHEK2 1100delC gene expression signature highlights pathways that are likely to have a role in the development of metastatic disease in carriers of CHEK2 1100delC mutation.
Project description:Differentially expressed genes between BRCA1/BRCA2 negative and positive mutation driven-tumors. Screening for germline mutations was performed in a cohort of 55 patients under the age of 35 years in the BRCA1, BRCA2, CHEK2 (c.del1,100C) and TP53 genes, and the respective tumors were investigated regarding hormonal receptors status, HER2 expression. Transcriptional profiles were performed using Agilent one color hybridizations in a G4112F platform.
Project description:This SuperSeries is composed of the following subset Series: GSE24697: Breast tumors from CHEK2 1100delC mutation carriers: genomic landscape and clinical implications (GEX) GSE24698: Breast tumors from CHEK2 1100delC mutation carriers: genomic landscape and clinical implications (CGH) Refer to individual Series
Project description:Introduction: CHEK2 is a moderate penetrance breast cancer risk gene, whose truncating mutation 1100delC increases the risk about two fold. We pursued to investigate gene copy number aberrations and gene expression profiles that are typical for breast tumors of CHEK2 1100delC mutation carriers. Materials and methods: A total of 126 breast tumor tissue specimens including 32 samples from patients carrying CHEK2 1100delC were studied in array comparative genomic hybridization (aCGH) and gene expression experiments (GEX). After dimensionality reduction with CGHregions R package, CHEK2 1100delC associated regions in the aCGH data were detected by Wilcoxon rank sum test. Linear model was fitted to GEX data with R package limma. Genes whose expression levels were associated with CHEK2 1100delC mutation were detected by Bayesian method. Results: We discovered four lost and three gained CHEK2 1100delC related loci. These include losses of 1p13.3-31.3, 8p21.1-2, 8p23.1-2 and 17p12-13.1 as well as gains of 12q13.11-3, 16p13.3 and 19p13.3. Twenty-eight genes located on these regions showed differential expression between CHEK2 1100delC and other tumors nominating them as candidates for CHEK2 1100delC associated tumor progression drivers. These included CLCA1 on 1p22 as well as CALCOCO1, SBEM and LRP1 on 12q13. Altogether 188 genes were differentially expressed between CHEK2 1100delC and other tumors. Of these, 144 had elevated and 44 lowered expression levels. Our results suggest WNT pathway as a driver of tumorigenesis in breast tumors of CHEK2 1100delC mutation carriers and a role for the olfactory receptor protein family in cancer progression. Differences in the expression of the 188 CHEK2 1100delC associated genes divided breast tumor samples from three independent datasets into two groups that differed in their relapse-free survival time. Conclusions: We have shown that copy number aberrations of certain genomic regions are associated with CHEK2 mutation 1100delC. On these regions we have identified potential drivers of CHEK2 1100delC associated tumorigenesis, whose role in cancer progression is worth investigating. Furthermore, poorer survival related to the CHEK2 1100delC gene expression signature highlights pathways that are likely to have a role in the development of metastatic disease in carriers of CHEK2 1100delC mutation.
2011-05-10 | GSE24697 | GEO
Project description:Predisposition to hematopoietic malignancies by deleterious germline CHEK2 variants
Project description:CHEK2 1100delC is a moderate-risk cancer susceptibility allele that confers a high breast cancer risk in a polygenic setting. Gene expression profiling of CHEK2 1100delC breast cancers may reveal clues to the nature of the polygenic CHEK2 model and its genes involved. Here, we report global gene expression profiles of a cohort of 155 familial breast cancers, including 26 CHEK2 1100delC mutant tumors. A 40-gene CHEK2 signature was defined that significantly associated with CHEK2 1100delC breast cancers. The identification of a CHEK2 gene signature implies an unexpected biological homogeneity among the CHEK2 1100delC breast cancers. In addition, all 26 CHEK2 1100delC tumors classified as luminal intrinsic subtype breast cancers, with 8 luminal A and 18 luminal B tumors. This biological make-up of CHEK2 1100delC breast cancers suggests that a relatively limited number of additional susceptibility alleles are involved in the polygenic CHEK2 model. Identification of these as-yet-unknown susceptibility alleles should be aided by clues from the 40-gene CHEK2 signature.