237 HBOC Patients negative for BRCA1/2 mutations
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE121968 | GEO | 2018/10/31
REPOSITORIES: GEO
Similar Datasets
Project description:Hereditary Breast and Ovarian Cancer syndrome patients BRCA1, BRCA2 and TP53 variants
| PRJNA837602 | ENA
Project description:89 tumors from women that were eligible for, and subjected to, routine diagnostic testing according to the HBOC criteria but were negative for pathogenic BRCA1/2-mutations or carried an UV in either BRCA1/2 A BRCA2-classifier was built using array-CGH profiles of 28 BRCA2-mutated and 28 sporadic breast tumors. The classifier was validated on an independent group of 19 BRCA2-mutated and 19 sporadic breast tumors. Subsequently, we tested 89 breast tumors from suspected hereditary breast (and ovarian) cancer (HBOC) families, in which either no BRCA1/2 mutation or an UV had been found by routine diagnostics.
2010-07-05 | E-GEOD-22481 | biostudies-arrayexpress
Project description:Pathogenic germline mutations in BRCA1 or BRCA2 are detected in less than one third of families with a strong history of breast cancer. It is therefore expected that mutations still remain undetected by currently used screening methods. In addition, a growing number of BRCA1/2 sequence variants of unclear pathogen significance are found in the families, constituting an increasing clinical challenge. New methods are therefore needed to improve the detection rate and aid the interpretation of the clinically uncertain variants. In this study we analyzed a series of 33 BRCA1, 22 BRCA2, and 128 sporadic tumors by RNA profiling to investigate the classification potential of RNA profiles to predict BRCA1/2 mutation status. We found that breast tumors from BRCA1 and BRCA2 mutation carriers display characteristic RNA expression patterns, allowing them to be distinguished from sporadic tumors. The majority of BRCA1 tumors were basal-like while BRCA2 tumors were mainly luminal B. Using RNA profiles, we were able to distinguish BRCA1 tumors from sporadic tumors among basal-like tumors with 83% accuracy and BRCA2 from sporadic tumors among luminal B tumors with 89% accuracy. Furthermore, subtype-specific BRCA1/2 gene signatures were successfully validated in two independent data sets with high accuracies. Although additional validation studies are required, indication of BRCA1/2 involvement (“BRCAness”) by RNA profiling could potentially be valuable as a tool for distinguishing pathogenic mutations from benign variants, for identification of undetected mutation carriers, and for selecting patients sensitive to new therapeutics such as PARP inhibitors. Gene expression profiling of 183 breast tumor samples. Breast tumors from hereditary breast cancer patients carrying a pathogenic BRCA1 (n=33) or BRCA2 (n=22) germ-line mutation were included in the study. Serving as a representative control group, primary breast tumor samples (n=128) were randomly selected. The study was conducted using Agilent-029949 Custom SurePrint G3 Human GE 8x60K Microarray platform. For cross-platform validation, a subset of the tumor samples (92 of the 183 samples) were analyzed by our in-house spotted microarray platform.
2013-06-28 | E-GEOD-40115 | biostudies-arrayexpress
Project description:We have analyzed, using DNA microarrays, putative differences in gene-expression level between hereditary BRCA1 mutation-linked and sporadic breast cancer. Our results show that a previously reported marked difference between BRCA1-mutation linked and sporadic breast cancer was probably due to uneven stratification of samples with different ER status and basal-like versus luminal-like subtype. We observed that apparent difference between BRCA1-linked and other types of breast cancer found in univariate analysis was diminished when data were corrected for ER status and molecular subtype in multivariate analyses. In fact, the difference in gene expression pattern of BRCA1-mutated and sporadic cancer is very discrete. These conclusions were supported by the results of Q-PCR validation. We also found that BRCA1 gene inactivation due to promoter hypermethylation had similar effect on general gene expression profile as mutation-induced protein truncation. This suggests that in the molecular studies of hereditary breast cancer, BRCA1 gene methylation should be recognized and considered together with gene mutation. We analyzed 35 breast cancer specimens. Surgical samples obtained during mastectomy were flash-frozen in liquid nitrogen and stored at -80°C. Only samples from patients without neoadjuvant chemotherapy were used in this study as chemotherapy may seriously affect gene expression profile. All tissue samples were collected at the Pomeranian Medical University in Szczecin. Seventeen tumor samples were collected from patients with hereditary breast cancer: 12 were derived from tumors affecting women with hereditary BRCA1 mutation, the only one from a woman with BRCA2 mutation, while another eight cases had familial history of breast/ovarian cancer, but were negative for the BRCA1/2 mutations (so called BRCAx cases). Proportion of BRCA1 and BRCA2 mutated tumors was typical for the Polish population. Ten samples were derived from patients with apparently sporadic disease (no familial history of cancer) while 4 patients had a history of familial cancer aggregation (FCA) but without prevalence of breast/ovarian cancers. Thus, these samples were merged with sporadic samples in most of the analyses. All BRCA1 mutation-linked tumors in our study were negative for estrogen receptor (by immunohistochemistry, standard procedures for ER, PGR and HER2 staining were applied), while the only BRCA2-mutated tumor was ER-positive. There were 26 ductal and 5 medullary carcinomas within the study group, which is consistent with the distribution of histopathological types in BRCA1 mutation carriers. Patients were diagnosed at stage T1-2, N0-1 and M0. Caution: this submission contains the data from 6 microarrays done on the normal/pathologically unchanged breast tissue from breast cancer patiets. The data from normal tissues was not analyzed in the paper BRCA1-related gene signature in breast cancer is strongly influenced by ER status and molecular type by Lisowska et al., 2011, Front Biosci (Elite Ed). 2011 Jan 1;3:125-36
2013-09-05 | E-GEOD-50567 | biostudies-arrayexpress
Project description:In more than 70% of families with a strong history of breast and ovarian cancers, pathogenic mutation in BRCA1 or BRCA2 cannot be identified, even though hereditary factors are expected to be involved. It has been proposed that tumors with similar molecular phenotypes also share similar pathophysiological mechanisms. Grouping into molecularly homogeneous subsets may therefore be of potential value for further genetic analysis in order to identify new high penetrance breast cancer genes. In the current study, the aim was to investigate if global RNA profiling can be used to identify functional subgroups within breast tumors from families tested negative for BRCA1/2 germline mutations and how these subgroupings relate to different breast cancer patients within the same family. By analyzing a collection of 70 breast tumor biopsies from 58 families, we show that distinct functional subgroupings, similar to the intrinsic molecular breast cancer subtypes, exist. The distribution of subtypes was markedly different from the distribution found among BRCA1/2 mutation carriers. From 11 breast cancer families, breast tumor biopsies from more than one affected family member were included in the study. Notably, in 8 of these families we found that patients from the same family shared the same tumor subtype, showing a tendency of familial aggregation of tumor subtypes (p-value = 1.7e-3). Our finding indicates involvement of hereditary factors in these families in which family members may carry genetic susceptibility not just to breast cancer but to a particular subtype of breast cancer. Using our previously developed BRCA1/2-signatures, we identified 7 non-BRCA1/2 tumors with a BRCA1-like molecular phenotype and provide evidence for epigenetic inactivation of BRCA1 in three of the tumors. In addition, 7 BRCA2-like tumors were found. This is the first study to provide a biological link between breast cancers from family members of high risk non-BRCA1/2 families in a systematic manner, suggesting that future genetic analysis may benefit from subgrouping families into molecularly homogeneous subtypes in order to identify new high penetrance susceptibility genes. Gene expression profiling of 253 breast tumor samples. Breast tumor tissue from 125 patients with germline mutations in BRCA1 (n = 33) or BRCA2 (n = 22) or with no detectable germline mutation in BRCA1 or BRCA2 (n = 70) were included in the study. Serving as a representative control group, primary breast tumor samples (n = 128) were randomly selected among available samples originating from the same department and time period as for the hereditary samples. The study was conducted using Agilent-029949 Custom SurePrint G3 Human GE 8x60K Microarray platform.
2015-08-01 | E-GEOD-49481 | biostudies-arrayexpress
Project description:BRCA1 (breast cancer 1, early onset) mutations confer a high breast and ovarian cancer risk. Most of BRCA1 cancer-predisposing mutations originate truncated proteins, but missense mutations have also been detected in familial breast and ovarian cancer patients. These variants are rare and their role in cancer predisposition is often difficult to ascertain. Our purpose in the present work was to study the molecular mechanisms affected in human cells by two BRCA1 missense variants both located in the second BRCA1 BRCT domain, M1775R and A1789T. These variants were isolated from familial breast cancer patients and their role in the pathogenesis of breast cancer was also investigated by a study previously performed by our group in yeast cells. Here we present a microarray study to compare the expression profiles of HeLa cells transfected with these two variants and HeLa cells transfected with BRCA1 wild type. Data analysis was performed by evaluating three comparisons: M1775R versus wild-type (M1775RvsWT-contrast), A1789T versus wild-type (A1789TvsWT-contrast) and the mutated BRCT domain versus wild-type (MutvsWT-contrast), obtained by considering the two variants as a unique BRCT mutation. We found 173 differentially expressed genes in MutvsWT-contrast, 201 in M1775RvsWT-contrast and 313 in A1789TvsWT-contrast. Our results showed that the considered BRCA1 variants had an impact on cell processes often deregulated in cancerogenesis, such as cell cycle progression and DNA damage response and repair. Thus, our study further supports the putative role in the pathogenesis of cancer of the M1775R and A1789T BRCA1 variants from a molecular point of view.
2012-06-01 | E-MTAB-761 | biostudies-arrayexpress
Project description:Background:This study was a hypothesis generating exploration of genomic data collected at diagnosis for 19 patients, who later participated in a clinical trial. BRCA1/2 germline mutation related hereditary cancers are candidates for new immune therapeutic interventions. However, contrary to what is expected of tumors with compromised DNA repair, a prominent tumor mutation burden (TMB) in hereditary breast and ovarian cancers in this cohort, was not correlated with high global immune activity in their microenvironments. More information is needed about the relationship between genomic instability, phenotypes and immune microenvironments of BRCA1/2 related hereditary tumors in order to find appropriate markers of immune activity and the most effective anticancer immune strategies. Methods:Mining and statistical analyses of the original DNA and RNA sequencing data and data available from The Cancer Genome Atlas (TCGA) were performed using the R computing environment. To interpret the data, we have used published literature and web available resources such as Gene Ontology Tools, The Cancer immunome Atlas (TCIA) and the Cancer Research Institute iAtlas. Results: We found that BRCA1/2 germline related breast and ovarian cancers do not represent a unique phenotypic identity, but that they express a range of phenotypes similar to sporadic cancers. Importantly, BRCA2 germline mutation related breast tumors have a different profile of genomic instability compared to those related to BRCA1. However, all breast and ovarian BRCA1/2 related tumors are characterized by high homologous recombination deficiency (HRD) and low aneuploidy. Interestingly, all sporadic high grade serous ovarian cancers (HGSOC) and most of the subtypes of triple negative breast cancers (TNBC), but not other types of breast cancer, also express a high degree of HRD. Conclusion: : Tumor mutation burdon (TMB) is not associated with the magnitude of the immune response in hereditary BRCA1/2 related breast and ovarian cancers or in sporadic TNBC and sporadic HGSOC. Hereditary tumors express phenotypes as heterogenous as sporadic tumors with various degree of “BRCAness” and various characteristics of the immune microenvironments. The subtyping criteria developed for sporadic tumors can be applied for the classification of hereditary tumors and possibly also characterization of their immune microenvironment. A high HRD score may be a good candidate biomarker for response to platinum, and potentially PARP-inhibition.
2019-11-28 | GSE141142 | GEO
Project description:We identified pathogenic and likely pathogenic variants in 17.8% of the patients within a wide range of cancer types. In particular, mesothelioma, ovarian cancer, cervical cancer, urothelial cancer, and cancer of unknown primary origin displayed high frequencies of pathogenic variants. In total, 22 BRCA1 and BRCA2 germline variant were identified in 12 different cancer types, of which 10 (45%) variants were not previously identified in these patients. Pathogenic germline variants were predominantly found in DNA repair pathways; approximately half of the variants were within genes involved in homologous recombination repair. Loss of heterozygosity and somatic second hits were identified in several of these genes, supporting possible causality for cancer development. A potential treatment target based on pathogenic germline variant could be suggested in 25 patients (4%).
2019-05-11 | GSE131027 | GEO
Project description:In more than 70% of families with a strong history of breast and ovarian cancers, pathogenic mutation in BRCA1 or BRCA2 cannot be identified, even though hereditary factors are expected to be involved. It has been proposed that tumors with similar molecular phenotypes also share similar pathophysiological mechanisms. Grouping into molecularly homogeneous subsets may therefore be of potential value for further genetic analysis in order to identify new high penetrance breast cancer genes. In the current study, the aim was to investigate if global RNA profiling can be used to identify functional subgroups within breast tumors from families tested negative for BRCA1/2 germline mutations and how these subgroupings relate to different breast cancer patients within the same family. By analyzing a collection of 70 breast tumor biopsies from 58 families, we show that distinct functional subgroupings, similar to the intrinsic molecular breast cancer subtypes, exist. The distribution of subtypes was markedly different from the distribution found among BRCA1/2 mutation carriers. From 11 breast cancer families, breast tumor biopsies from more than one affected family member were included in the study. Notably, in 8 of these families we found that patients from the same family shared the same tumor subtype, showing a tendency of familial aggregation of tumor subtypes (p-value = 1.7e-3). Our finding indicates involvement of hereditary factors in these families in which family members may carry genetic susceptibility not just to breast cancer but to a particular subtype of breast cancer. Using our previously developed BRCA1/2-signatures, we identified 7 non-BRCA1/2 tumors with a BRCA1-like molecular phenotype and provide evidence for epigenetic inactivation of BRCA1 in three of the tumors. In addition, 7 BRCA2-like tumors were found. This is the first study to provide a biological link between breast cancers from family members of high risk non-BRCA1/2 families in a systematic manner, suggesting that future genetic analysis may benefit from subgrouping families into molecularly homogeneous subtypes in order to identify new high penetrance susceptibility genes.
2015-08-01 | GSE49481 | GEO
Project description:While new defects in BRCA1 are still being found, it is unclear whether current breast cancer diagnostics misses many BRCA1-associated cases. A reliable test that is able to indicate the involvement of BRCA1 deficiency in cancer genesis could support decision making in genetic counselling and clinical management. To find BRCA1-specific markers and explore the effectiveness of the current diagnostic strategy, we designed a classification method, validated it and examined whether we could find BRCA1-like breast tumours in a group of patients initially diagnosed as non-BRCA1/2 mutation carriers. A classifier was built based on array-CGH profiles of 18 BRCA1-related and 32 control breast tumours, and validated on independent sets of 16 BRCA1-related and 16 control breast carcinomas. Subsequently, we applied the classifier to 48 breast tumours of patients from Hereditary Breast and Ovarian Cancer (HBOC) families in whom no germ line BRCA1/BRCA2 mutations were identified. The classifier showed an accuracy of 91% when applied to the validation sets. In 48 non-BRCA1/2 patients, only two breast tumours presented a BRCA1-like CGH profile. Additional evidence for BRCA1 dysfunction was found in one of these tumours. We here describe the specific chromosomal aberrations in BRCA1-related breast carcinomas. We developed a predictive genetic test for BRCA1-association and show that BRCA1-related tumours can still be identified in HBOC families after routine DNA diagnostics.
2010-12-02 | GSE9021 | GEO