Mutation of the breast cancer -associated gene 1 (BRCA1) plays an important role in familial breast cancer. Although hypermethylation of the BRCA1 promoter has been observed in sporadic breast cancer, its exact role in breast cancer initiation and association with breast cancer risk is unknown. The frequency of BRCA1 promoter hypermethylation was tested in (a) 14 primary breast cancer biopsies and (b) the initial random periareolar fine-needle aspiration (RPFNA) cytologic samples obtained from 61 asymptomatic women who were at increased risk for breast cancer. BRCA1 promoter hypermethylation was assessed from nucleotide À150 to nucleotide +32 relative to the transcription start site. RPFNA specimens were stratified for cytologic atypia using the Masood cytology index. BRCA1 promoter hypermethylation was observed at similar frequency in nonproliferative (normal; Masood V10: 18%, 2 of 11), hyperplastic (Masood 11-13: 15%, 6 of 41), and atypical cytology (Masood 14-17: 22%, 4 of 18; P = 0.79). BRCA1 promoter hypermethylation was not associated with (a) family history of breast or ovarian cancer or (b) calculated Gail or BRCAPRO risk score. BRCA1 promoter hypermethylation was associated with (a) age (P = 0.028) and (b) the combined frequency of promoter hypermethylation of the retinoic acid receptor-b2 (RARB) gene, estrogen receptor-a (ESR1) gene, and p16 (
Our study suggests a new role for FLX as an inducer of ER stress and autophagy, resulting in death of aggressive triple negative breast cancer SUM149PT.
Random periareolar fine needle aspiration (RPFNA) and ductal lavage (DL) are research techniques developed to (1) assess short-term breast cancer risk in asymptomatic women who are at increased risk for breast cancer and (2) track cytological response to risk reduction strategies. RPFNA and DL provide minimally invasive methods to repeatedly sample epithelial cells and research tools to investigate the biological origins of breast cancer in high-risk women. This review gives an overview of the strengths and limitations of both RPFNA and DL for risk assessment and breast cancer prevention in asymptomatic high-risk women.
CREB-binding protein (CBP) is an important coactivator of basal transcription machinery and a critical regulator of cellular proliferation, differentiation, and apoptosis. It is hypothesized that CBP function is regulated by post-translational modifications, such as phosphorylation and methylation. Specific kinase-mediated phosphorylation of CBP has been shown to affect not only intrinsic histone acetyl transferase activity, but also transcriptional activity of various target promoters and interaction with binding partners. While most of the identified CBP phosphorylation sites have been mapped to the N-terminus of the protein, based on previous studies of the CBP homolog (p300), Protein Kinase B/Akt is predicted to phosphorylate the C-terminus of CBP. However, there is no direct evidence of Akt-mediated phosphorylation of CBP. Here we report the first purification procedure of recombinant fragment of CBP, encompassing the cysteine/histidine-rich domain 3 (CH3) and glutamine-rich (Q) domain of the protein, which is suitable for structural and interaction studies. We provide the first evidence of protein-protein interaction between the full-length Akt1 and the C-terminus of CBP by fluorescence spectroscopy and the subsequent phosphorylation of CBP by in vitro phosphorylation assay. Our results suggest that Akt signaling may have important implications on the in vivo molecular interaction of CBP with various transcription factors and modulation of cellular responses.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.