Promoter hypermethylation of BRCA1 correlates with absence of expression in hereditary breast cancer tumors

@article{Tapia2008PromoterHO,
  title={Promoter hypermethylation of BRCA1 correlates with absence of expression in hereditary breast cancer tumors},
  author={Teresa Tapia and Susan V. Smalley and Paulina Kohen and Alex Mu{\~n}oz and Luisa Maren Solis and Alejandro H. Corval{\'a}n and Paola Fa{\'u}ndez and Luigi Devoto and Mauricio Camus and Manuel {\'A}lvarez and Pilar Carvallo},
  journal={Epigenetics},
  year={2008},
  volume={3},
  pages={157 - 163}
}
Germline mutations in BRCA1 account for a low proportion of hereditary cases in diverse populations. Several efforts have been made to find new genes involved in the inheritance of breast cancer with no success until today. The participation of BRCA1 in the development of breast cancer has been proposed in several studies where hypermethylation of its promoter and a decrease in expression has been reported for sporadic cases and one study on familial cases. To explore the participation of BRCA1… 
Methylation profiles of the BRCA1 promoter in hereditary and sporadic breast cancer among Han Chinese
TLDR
The results suggest that there might be different BRCA1 promoter methylation levels and patterns in sporadic and hereditary breast cancer in peripheral blood DNA, which may facilitate the early diagnosis of hereditary breast cancers.
Inherited BRCA1 epimutation as a novel cause of breast and ovarian cancer
TLDR
The results indicate a novel mechanism for familial breast/ovarian cancer, caused by epigenetic silencing of the BRCA1 promoter, segregating with an in cis 5’UTR variant in two independent families and propose that methylation analyses are indicated in all families affected by early onset breast/OVarian cancer without a BRCa1/2 pathogenic variant.
BRCA1 Promoter Hypermethylationas an Early Diagnostic Tool for Breast Cancer
TLDR
It is suggested that BRCA1 aberrant promoter hypermethylation in Kashmiri population contributes to the process of carcinogenesis in breast cancer and is reportedly one of the commonest epigenetic changes in the development of breast cancer.
Methylation not a frequent “second hit” in tumors with germline BRCA mutations
TLDR
Data indicate that promoter methylation is a not a frequent “second-hit” in tumors from BRCA1 or BRCa2 carriers.
Pathology of hereditary breast cancer
TLDR
A better understanding of the morphological, immunohistochemical and molecular characteristics of different types of hereditary breast cancers is led, which offer clues for diagnosis and new therapeutic approaches.
Hereditary Breast Cancer: Clinical, Pathological and Molecular Characteristics
TLDR
An overview of hereditary breast cancer, its genetic background, and clinical implications are provided, before focusing on the pathologically and molecular features associated with the disease.
Etiology of familial breast cancer with undetected BRCA1 and BRCA2 mutations: clinical implications
TLDR
Current evidence suggests that in the majority of cases with BRCA1 and BRCa2 negative familial breast cancer the etiology is due to interactions of intermediate or low risk alleles with environmental and lifestyle factors, and a careful selection of patients submitted to genetic testing is needed.
BRCA promoter methylation in sporadic versus BRCA germline mutation-related breast cancers
TLDR
The diagnostic value of BRCA promoter methylation analysis in distinguishing BRCa1/2-related from sporadic breast carcinomas seems to be considerably dependent on the targeted CpG sites, which is important for adequate use of B RCAmethylation analysis as a prescreening tool for BRC a germline genetic testing or to identify patients who may benefit from targeted therapies like poly(adenosine diphosphate-ribose) polymerase inhibitors.
BRCA1 promoter hypermethylation signature for early detection of breast cancer in the Vietnamese population.
TLDR
The DNA hypermethylation of this candidate gene increased the possibility to be breast cancer with high incidence via calculated odd ratios and could be used as the promising biomarker application with Vietnamese breast cancer patients.
Prognostic Relevance of BRCA1 Expression in Survival of Patients With Cervical Cancer
TLDR
BRCA 1 expression in cervical cancer tissue is associated with survival and the identification of specific gene alterations associated with BRCA1 expression could help to provide individualized prediction in these patients.
...
1
2
3
4
5
...

References

SHOWING 1-10 OF 34 REFERENCES
Promoter hypermethylation and BRCA1 inactivation in sporadic breast and ovarian tumors.
BACKGROUND Inherited mutations in the BRCA1 gene may be responsible for almost half of inherited breast carcinomas. However, somatic (acquired) mutations in BRCA1 have not been reported, despite
BRCA1 promoter region hypermethylation in ovarian carcinoma: a population-based study.
TLDR
Promoter hypermethylation may be an alternative to mutation in causing the inactivation of the BRCA1 tumor suppressor gene in sporadic ovarian cancer.
Methylation of the BRCA1 promoter region in sporadic breast and ovarian cancer: correlation with disease characteristics
TLDR
It is suggested that abnormal methylation of the BRCA1 promoter may be important in tumorigenesis in a subset of sporadic breast and ovarian cancers.
Methylation of the BRCA1 gene in sporadic breast cancer.
TLDR
Hypermethylation was observed in two of seven sporadic breast carcinomas but not in any normal tissues, consistent with an important role for epigenetic mechanisms in human cancer.
BRCA1 promoter methylation in sporadic breast cancer is associated with reduced BRCA1 copy number and chromosome 17 aneusomy.
TLDR
The data support a model of carcinogenesis in which BRCA1 promoter methylation may serve as a "first hit," much like an inherited germ line mutation, and promote tumor progression down a restricted set of molecular pathways.
Epigenetic silencing and deletion of the BRCA1 gene in sporadic breast cancer
TLDR
It is found that epigenetic silencing and deletion of the BRCA1 gene might serve as Knudson's two 'hits' in sporadic breast tumorigenesis as well as young-age at diagnosis and tumour grade.
Incidence of BRCA1 and BRCA2 mutations in 54 Chilean families with breast/ovarian cancer, genotype–phenotype correlations
TLDR
The findings suggest that the history of colonization and immigrations is very relevant when studying hereditary factors associated to breast cancer, such as lifestyle risk factors, geographic location, country of origin and socioeconomic status.
BRCA1 promoter methylation in sporadic breast tumors: relationship to gene expression profiles
TLDR
It is found BRCA1 protein expression correlates with tumor mitotic rate, consistent with normal cell-cycle regulation of the BRCa1 gene, and the absence of BRC a1 promoter methylation and high levels of B RCA1 expression in basal-like sporadic tumors suggest alternate explanations for the phenotypic similarities of these tumors.
Tumour-specific distribution of BRCA1 promoter region methylation supports a pathogenetic role in breast and ovarian cancer.
TLDR
The rarity of observed BRCA1 mutations in sporadic breast and ovarian cancer is suggested to be due to the greater likelihood of BRCa1 inactivation by non-mutational mechanisms such as methylation.
Localization of human BRCA1 and its loss in high-grade, non-inherited breast carcinomas
TLDR
Immunohistochemical staining of human breast specimens revealed BRCA1 nuclear foci in benign breast, invasive lobular cancers and low–grade ductal carcinomas, suggesting that absence of BRCa1 may contribute to the pathogenesis of a significant percentage of sporadic breast cancers.
...
1
2
3
4
...