Both arsenic and cadmium are reported to be toxic to humans. The use of saliva as a biomarker of low-level exposures to these elements has not been adequately explored, and the putative relationship between exposure and obesity is unclear. This cross-sectional study aims to investigate the relationship between salivary arsenic and cadmium concentrations and their association with obesity.
View Article and Find Full Text PDFImmune response to a given antigen, particularly in cancer patients, is complex and is controlled by various genetic and environmental factors. Identifying biomarkers that can predict robust response to immunization is an urgent need in clinical cancer vaccine development. Given the involvement of DNA methylation in the development of lymphocytes, tumorigenicity and tumor progression, we aimed to analyze pre-vaccination DNA methylation profiles of peripheral blood mononuclear cells (PBMCs) from breast cancer subjects vaccinated with a novel peptide-based vaccine referred to as P10s-PADRE.
View Article and Find Full Text PDFObjectives: Rural women are underrepresented in cancer research. We hypothesized that providing access to a research study to rural, medically underserved women who were receiving their breast cancer screening using a mobile mammography unit would increase the representation of rural women in a cancer cohort study.
Design: This study is a cross-sectional study using a cohort of women who have been recruited to a breast cancer study in Arkansas.
The purpose of this study was to (a) describe the development of a culturally appropriate glucose monitoring video using a community-based participatory research approach and (b) assess the cultural appropriateness and effectiveness of the video. The topic of the video-using a glucometer and the importance of performing blood glucose checks-was chosen by Marshallese community stakeholders. The video was produced in Marshallese with English subtitles and disseminated through YouTube.
View Article and Find Full Text PDFBackground: Physical activity has been identified as a modifiable risk factor for breast cancer. Varying definitions of physical activity have made the evaluation difficult to analyze. In a state with high prevalence of obesity and elevated rates of breast cancer incidence and mortality, physical activity may be an important element for risk reduction.
View Article and Find Full Text PDFIntroduction: GATA3 is a critical transcription factor in maintaining the differentiated state of luminal mammary epithelial cells. We sought to determine the prognostic and predictive roles of GATA3 genotypes for breast cancer.
Patients And Methods: Twelve single nucleotide polymorphisms (SNPs) were genotyped in 2 breast cancer cohorts, including the SWOG S8897 trial where patients were treated with adjuvant chemotherapy (CAF [cyclophosphamide, doxorubicin, 5-fluorouracil] vs.
The transporter associated with antigen processing 2 (TAP2) is involved in the development of multidrug resistance and the etiology of immunological diseases. In this study, we investigated whether the expression of TAP2 can be perturbed by single nucleotide polymorphisms (SNPs) located in 3'-untranslated region (3'-UTR) of the gene via interactions with microRNAs. Using a series of in silico assays, we selected the candidate microRNAs (miRNAs) with the potential to interact with functional SNPs of TAP2.
View Article and Find Full Text PDF1. Human cytosolic sulfotransferase 1B1 (SULT1B1) sulfates small phenolic compounds and bioactivates polycyclic aromatic hydrocarbons. To date, no SULT1B1 allelic variants have been well-characterized.
View Article and Find Full Text PDFBackground: We previously reported improved pathologic complete response (pCR) in a prospective phase II study using neoadjuvant bevacizumab in combination with chemotherapy compared to chemotherapy alone in breast cancer patients (41% vs. 25%, p = 0.0291).
View Article and Find Full Text PDFObserved variations in drug responses among patients may result from differences in heritable genetic traits or from alterations in the epigenetic regulation of drug metabolizing enzymes and transporters (DMETs). MicroRNAs (miRNAs), a group of small non-coding RNAs, provide an epigenetic mechanism for fine-tuning the expression of targeted DMET genes by regulating the efficiency of protein translation and by decreasing mRNA stability via enhanced degradation. In the current study we systematically screened 374 important genes encoding DMETs for potential response elements to hsa-miR-29a-3p, a highly abundant miRNA in human liver.
View Article and Find Full Text PDFIncreased aerobic glycolysis and de novo lipid biosynthesis are common characteristics of invasive cancers. UDP-glucuronosyltransferases (UGTs) are phase II drug metabolizing enzymes that in normal cells possess the ability to glucuronidate these lipids and speed their excretion; however, de-regulation of these enzymes in cancer cells can lead to an accumulation of bioactive lipids, which further fuels cancer progression. We hypothesize that UGT2B isoform expression is down-regulated in cancer cells and that exogenous re-introduction of these enzymes will reduce lipid content, change the cellular phenotype, and inhibit cancer cell proliferation.
View Article and Find Full Text PDFThe development of breast cancer is linked to the loss of estrogen receptor (ER) during the course of tumor progression, resulting in loss of responsiveness to hormonal treatment. The mechanisms underlying dynamic ERα gene expression change in breast cancer remain unclear. A range of physiological and biological changes, including increased adipose tissue hypoxia, accompanies obesity.
View Article and Find Full Text PDFCYP19A1 facilitates the bioconversion of estrogens from androgens. CYP19A1 intron single nucleotide polymorphisms (SNPs) may alter mRNA splicing, resulting in altered CYP19A1 activity, and potentially influencing disease susceptibility. Genetic studies of CYP19A1 SNPs have been well documented in populations of European ancestry; however, studies in populations of African ancestry are limited.
View Article and Find Full Text PDFThe Gail and CARE models estimate breast cancer risk for white and African-American (AA) women, respectively. The aims of this study were to compare metropolitan and nonmetropolitan women with respect to predicted breast cancer risks based on known risk factors, and to determine if population density was an independent risk factor for breast cancer risk. A cross-sectional survey was completed by 15,582 women between 35 and 85 years of age with no history of breast cancer.
View Article and Find Full Text PDFDrug Metab Dispos
September 2014
Tamoxifen (Tam) is a selective estrogen receptor modulator used to inhibit breast tumor growth. Tam can be directly N-glucuronidated via the tertiary amine group or O-glucuronidated after cytochrome P450-mediated hydroxylation. In this study, the glucuronidation of Tam and its hydroxylated and/or chlorinated derivatives [4-hydroxytamoxifen (4OHTam), toremifene (Tor), and 4-hydroxytoremifene (4OHTor)] was examined using recombinant human UDP-glucuronosyltransferases (UGTs) from the 1A subfamily and human hepatic microsomes.
View Article and Find Full Text PDFBackground: Sulfotransferase 1A1 (SULT1A1) gene expression is tissue specific, with little to no expression in normal breast epithelia. Expression in breast tumors has been documented, but the transcriptional regulation of SULT1A1 in human breast tissue is poorly understood. We identified Nuclear Factor I (NFI) as a transcription factor family involved in the regulation of SULT1A1 expression.
View Article and Find Full Text PDFSulfotransferase (SULT) 1A1 is the major drug/xenobiotic-conjugating SULT isoform in human liver because of its broad substrate reactivity and high expression level. SULT1A1 sulfates estrogens with low micromolar K(m) values consistent with its affinity for sulfation of many small phenolic compounds. Binding studies showed the unexpected ability of 17α-ethinylestradiol (EE2) to bind and inhibit SULT1A1 activity toward p-nitrophenol and β-naphthol at low nanomolar concentrations, whereas EE2 was not sulfated until significantly higher concentrations were reached.
View Article and Find Full Text PDFThe Janus kinase (JAK)/signal transducer and activator of transcription (STAT) signaling pathway is involved in immune function and cell growth. We evaluated the association between genetic variation in JAK1 (10 SNPs), JAK2 (9 SNPs), TYK2 (5 SNPs), suppressors of cytokine signaling (SOCS)1 (2 SNPs), SOCS2 (2 SNPs), STAT1 (16 SNPs), STAT2 (2 SNPs), STAT3 (6 SNPs), STAT4 (21 SNPs), STAT5A (2 SNPs), STAT5B (3 SNPs), STAT6 (4 SNPs) with risk of colorectal cancer. We used data from population-based case-control studies (colon cancer n = 1555 cases, 1,956 controls; rectal cancer n = 754 cases, 959 controls).
View Article and Find Full Text PDFHorm Mol Biol Clin Investig
December 2010
Mammalian cytosolic sulfotransferases (SULTs) frequently show substrate inhibition during the sulfation of increasing concentrations of substrates. SULT2A1, a major human liver isoform responsible for the conjugation of hydroxysteroids, bile acids and aliphatic hydroxyl groups in drugs and xenobiotics, is a homodimer and displays substrate inhibition during the conjugation of dehydroepiandrosterone (DHEA). Maltose binding protein (MBP)-SULT2A1 fusion protein, produced as an intermediate step in the purification of the SULT2A1 homodimer, elutes during size exclusion chromatography as a monomer.
View Article and Find Full Text PDFBr J Clin Pharmacol
December 2010
Aims: Little information is available regarding the metabolic routes of anastrozole and the specific enzymes involved. We characterized anastrozole oxidative and conjugation metabolism in vitro and in vivo.
Methods: A sensitive LC-MS/MS method was developed to measure anastrozole and its metabolites in vitro and in vivo.
Horm Mol Biol Clin Investig
December 2010
Mammalian cytosolic sulfotransferases (SULTs) frequently show substrate inhibition during the sulfation of increasing concentrations of substrates. SULT2A1, a major human liver isoform responsible for the conjugation of hydroxysteroids, bile acids and aliphatic hydroxyl groups in drugs and xenobiotics, is a homodimer and displays substrate inhibition during the conjugation of dehydroepiandrosterone (DHEA). Maltose binding protein (MBP)-SULT2A1 fusion protein, produced as an intermediate step in the purification of the SULT2A1 homodimer, elutes during size exclusion chromatography as a monomer.
View Article and Find Full Text PDFHorm Mol Biol Clin Investig
January 2010
BACKGROUND: Human cytosoloic sulfotransferase (SULT) 2A1 is a major hepatic isoform and sulfates hydroxyl groups in structurally diverse sterols and xenobiotics. SULT2A1 crystal structures resolved in the presence and absence of 3',5'-diphosphoadenosine (PAP) or dehydropeiandrosterone (DHEA) suggest a significant rearrangement of the peptide that forms the surface of the active site in the presence of PAP. MATERIALS AND METHODS: Molecular modeling was used to examine the effects of the rearrangement in SULT2A1 associated with 3'-phosphoadenosine 5'-phosphosulfate (PAPS) binding on the binding of DHEA and raloxifene.
View Article and Find Full Text PDFPreviously, we reported a strong association of the high activity SULT1A1*1 allele and overall survival of patients receiving tamoxifen therapy, indicating that sulfation of 4-hydroxytamoxifen (4-OHT) via SULT1A1 may contribute to the therapeutic efficacy of tamoxifen treatment. In most, but not all cases, sulfation is considered to be an elimination pathway; therefore we sought to define the biological mechanism by which increased sulfation of tamoxifen could provide a therapeutic benefit. We compared the antiproliferative and apoptotic responses between MCF7-SULT1A1 expressing cells and control MCF7 pcDNA3 cells when treated with 4-OHT.
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