Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 27
Filter
1.
FASEB J ; 35(6): e21551, 2021 06.
Article in English | MEDLINE | ID: mdl-34042222

ABSTRACT

Intestinal epithelial cells (IEC) are crucial for maintaining proper digestion and overall homeostasis of the gut mucosa. IEC proliferation and differentiation are tightly regulated by well described pathways, however, relatively little is known about how cytokines shape these processes. Given that the anti-inflammatory cytokine interleukin (IL)-10 promotes intestinal barrier function, and insufficient IL-10 signaling increases susceptibility to intestinal diseases like inflammatory bowel disease, we hypothesized that IL-10 signaling modulates processes underlying IEC proliferation and differentiation. This was tested using in vivo and in vitro IEC-specific IL-10 receptor 1 (IL-10R1) depletion under homeostatic conditions. Our findings revealed that loss of IL-10R1 drove lineage commitment toward a dominant goblet cell phenotype while decreasing absorptive cell-related features. Diminished IL-10 signaling also significantly elevated IEC proliferation with relatively minor changes to apoptosis. Characterization of signaling pathways upstream of proliferation demonstrated a significant reduction in the Wnt inhibitor, DKK1, increased nuclear localization of ß-catenin, and increased transcripts of the proliferation marker, OLFM4, with IL-10R1 depletion. Phosphorylated STAT3 was nearly completely absent in IL-10R1 knockdown cells and may provide a mechanistic link between our observations and the regulation of these cellular processes. Our results demonstrate a novel role for IL-10 signaling in intestinal mucosal homeostasis by regulating proper balance of proliferation and IEC lineage fate.


Subject(s)
Cell Differentiation , Cell Proliferation , Epithelial Cells/pathology , Goblet Cells/pathology , Intestinal Mucosa/pathology , Receptors, Interleukin-10/physiology , Animals , Apoptosis , Epithelial Cells/metabolism , Female , Goblet Cells/metabolism , Intestinal Mucosa/metabolism , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Signal Transduction
2.
Genet Med ; 23(8): 1458-1464, 2021 08.
Article in English | MEDLINE | ID: mdl-33941882

ABSTRACT

PURPOSE: This study characterizes the US clinical genetics workforce to inform workforce planning and public policy development. METHODS: A 32-question survey was electronically distributed to American Board of Medical Genetics and Genomics board-certified/eligible diplomates in 2019. We conducted a descriptive analysis of responses from practicing clinical geneticists. RESULTS: Of the 491 clinical geneticists responding to the survey, a majority were female (59%) and White (79%), worked in academic medical centers (73%), and many engaged in telemedicine (33%). Clinical geneticists reported an average of 13 new and 10 follow-up patient visits per week. The average work week was 50 hours and the majority (58%) worked over half-time in clinical duties. Providers indicated that 39% of new emergency patients wait 3 days or more, and 39% of nonemergency patients wait over 3 months to be seen. Respondents were geographically concentrated in metropolitan areas and many reported unfilled clinical geneticist job vacancies at their institution of more than 3 years. CONCLUSION: With the rapid expansion of genomic medicine in the past decade, there is still a gap between genetics services needed and workforce capacity. A concerted effort is required to increase the number of clinical geneticists and enhance interdisciplinary teamwork to meet increasing patient needs.


Subject(s)
Genetics, Medical , Medicine , Physicians , Female , Genetic Services , Humans , Male , United States , Workforce
3.
Breast J ; 27(7): 573-580, 2021 07.
Article in English | MEDLINE | ID: mdl-33738890

ABSTRACT

BACKGROUND: Breast cancer mortality rates are 39% higher in the African-American (AA) women compared to White-American (WA) women despite the advances in overall breast cancer screening and treatments. Several studies have undertaken to identify the factors leading to this disparity in United States with possible effects of lower socioeconomic status and underlying aggressive biology. METHODS: A retrospective analysis was done using a prospectively maintained database of a metropolitan health system. Patients were selected based on diagnosis of early-stage breast cancer between 10/1998 and 02/2017, and included women over age of 18 with clinically node-negative disease. Patients were then stratified by phenotype confirmed by pathology and patient-identified race. RESULTS: A total of 2,298 women were identified in the cohort with 39% AA and 61% WA women. The overall mean age at the time of diagnosis for AA women was slightly younger at 60 years compared to 62 years for WA women (p = 0.003). Follow-up time was longer for the WA women at 95 months vs. 86 months in AA women. The overall 5-year survival was analyzed for the entire cohort, with the lowest survival occurring in patients with triple-negative breast cancer (TNBC). Phenotype distribution revealed a higher incidence of TNBC in AA women compared to WA women (AA 16% vs. WA 10%; p < 0.0001). AA women also had higher incidence of HER2 positive cancers (AA 16.8% vs. WA 15.3%; p < 0.0001). WA women had a significantly higher distribution of Non-TNBC/HER2-negative phenotype (AA 55% vs. WA 65%; p < 0.0001). Furthermore, a subgroup analysis was done for a sentinel lymph node (SLN) negative cohort that showed higher rates of grade 3 tumors in AA (AA 35% vs. WA 23%; p < 0.0001); and higher rates of grade 1 and grade 2 tumors in WA (30% vs. 21% and 44% vs. 40%). Despite higher grade tumors in AA women, five-year overall survival outcomes in SLN-negative cohort did not differ between AA and WA women when stratifying based on tumor subtype. CONCLUSION: Breast cancer survival disparities in AA and WA women with SLN-negative breast cancer are diminished when evaluated at early-stage cancers defined by SLN-negative tumors. Our evaluation suggests that when diagnosed early, phenotype does not contribute to racial survival outcomes. The lower survival rate in AA women with breast cancer may be attributed to later stage biology between the two races, or underlying socioeconomic disparities.


Subject(s)
Breast Neoplasms , Triple Negative Breast Neoplasms , Black or African American , Female , Humans , Phenotype , Retrospective Studies , United States/epidemiology , White People
4.
Am J Physiol Gastrointest Liver Physiol ; 317(4): G531-G544, 2019 10 01.
Article in English | MEDLINE | ID: mdl-31393789

ABSTRACT

Restitution of wounds in colonic epithelium is essential in the maintenance of health. Microbial products, such as the short-chain fatty acid butyrate, can have positive effects on wound healing. We used an in vitro model of T84 colonic epithelial cells to determine if the Snail genes Slug (SNAI2) and Snail (SNAI1), implemented in keratinocyte monolayer healing, are involved in butyrate-enhanced colonic epithelial wound healing. Using shRNA-mediated Slug/Snail knockdown, we found that knockdown of Slug (Slug-KD), but not Snail (Snail-KD), impairs wound healing in scratch assays with and without butyrate. Slug and Snail had differential effects on T84 monolayer barrier integrity, measured by transepithelial resistance, as Snail-KD impaired the barrier (with or without butyrate), whereas Slug-KD enhanced the barrier, again with or without butyrate. Targeted transcriptional analysis demonstrated differential expression of several tight junction genes, as well as focal adhesion genes. This included altered regulation of Annexin A2 and ITGB1 in Slug-KD, which was reflected in confocal microscopy, showing increased accumulation of B1-integrin protein in Slug-KD cells, which was previously shown to impair wound healing. Transcriptional analysis also indicated altered expression of genes associated with epithelial terminal differentiation, such that Slug-KD cells skewed toward overexpression of secretory cell pathway-associated genes. This included trefoil factors TFF1 and TFF3, which were expressed at lower than control levels in Snail-KD cells. Since TFFs can enhance the barrier in epithelial cells, this points to a potential mechanism of differential modulation by Snail genes. Although Snail genes are crucial in epithelial wound restitution, butyrate responses are mediated by other pathways as well.NEW & NOTEWORTHY Although butyrate can promote colonic mucosal healing, not all of its downstream pathways are understood. We show that the Snail genes Snail and Slug are mediators of butyrate responses. Furthermore, these genes, and Slug in particular, are necessary for efficient restitution of wounds and barriers in T84 epithelial cells even in the absence of butyrate. These effects are achieved in part through effects on regulation of ß1 integrin and cellular differentiation state.


Subject(s)
Butyrates/therapeutic use , Colonic Diseases/drug therapy , Colonic Diseases/genetics , Snail Family Transcription Factors/genetics , Wound Healing/drug effects , Wound Healing/genetics , Adaptor Proteins, Signal Transducing/genetics , Adaptor Proteins, Signal Transducing/metabolism , Cell Line , Gene Knockdown Techniques , Humans , Signal Transduction/drug effects , Tight Junction Proteins/drug effects , Tight Junction Proteins/genetics , Trefoil Factor-1/biosynthesis , Trefoil Factor-1/genetics , Trefoil Factor-3/biosynthesis , Trefoil Factor-3/genetics
5.
Ann Surg ; 270(3): 484-492, 2019 09.
Article in English | MEDLINE | ID: mdl-31356281

ABSTRACT

OBJECTIVE: To investigate subtype-specific risk of germline alleles associated with triple negative breast cancer (TNBC) in African ancestry populations. BACKGROUND: Breast cancer (BC) mortality is higher in African American (AA) compared to White American (WA) women; this disparity is partly explained by 2-fold higher TNBC incidence. METHODS: We used a surgically maintained biospecimen cohort of 2884 BC cases. Subsets of the total (760 AA; 962 WA; 910 West African/Ghanaian; 252 East African/Ethiopian) were analyzed for genotypes of candidate alleles. A subset of 417 healthy controls were also genotyped, to measure associations with overall BC risk and TNBC. RESULTS: TNBC frequency was highest in Ghanaian and AA cases (49% and 44% respectively; P < 0.0001) and lowest in Ethiopian and WA cases (17% and 24% respectively; P < 0.0001). TNBC cases had higher West African ancestry than non-TNBC (P < 0.0001). Frequency of the Duffy-null allele (rs2814778; an African ancestral variant adopted under selective pressure as protection against malaria) was associated with TNBC-specific risk (P < 0.0001), quantified West African Ancestry (P < 0.0001) and was more common in AA, Ghanaians, and TNBC cases. Additionally, rs4849887 was significantly associated with overall BC risk, and both rs2363956 and rs13000023 were associated with TNBC-specific risk, although none as strongly as the Duffy-null variant. CONCLUSIONS: West African ancestry is strongly correlated with TNBC status, as well as germline variants related to BC risk. The Duffy-null allele was associated with TNBC risk in our cohort.


Subject(s)
Black or African American/genetics , Disease Susceptibility/epidemiology , Germ-Line Mutation/genetics , Receptor, ErbB-2/genetics , Triple Negative Breast Neoplasms/genetics , Adult , Africa South of the Sahara/ethnology , Aged , Case-Control Studies , Databases, Factual , Female , Ghana/ethnology , Humans , Incidence , Internationality , Middle Aged , Receptors, Estrogen/genetics , Receptors, Progesterone/genetics , Risk Assessment , Triple Negative Breast Neoplasms/ethnology , Triple Negative Breast Neoplasms/pathology , United States
6.
Am J Pathol ; 188(5): 1183-1194, 2018 05.
Article in English | MEDLINE | ID: mdl-29454749

ABSTRACT

Interactions between the gut microbiota and the host are important for health, where dysbiosis has emerged as a likely component of mucosal disease. The specific constituents of the microbiota that contribute to mucosal disease are not well defined. The authors sought to define microbial components that regulate homeostasis within the intestinal mucosa. Using an unbiased, metabolomic profiling approach, a selective depletion of indole and indole-derived metabolites was identified in murine and human colitis. Indole-3-propionic acid (IPA) was selectively diminished in circulating serum from human subjects with active colitis, and IPA served as a biomarker of disease remission. Administration of indole metabolites showed prominent induction of IL-10R1 on cultured intestinal epithelia that was explained by activation of the aryl hydrocarbon receptor. Colonization of germ-free mice with wild-type Escherichia coli, but not E. coli mutants unable to generate indole, induced colonic epithelial IL-10R1. Moreover, oral administration of IPA significantly ameliorated disease in a chemically induced murine colitis model. This work defines a novel role of indole metabolites in anti-inflammatory pathways mediated by epithelial IL-10 signaling and identifies possible avenues for utilizing indoles as novel therapeutics in mucosal disease.


Subject(s)
Colitis/metabolism , Indoles/metabolism , Intestinal Mucosa/metabolism , Microbiota/physiology , Receptors, Interleukin-10/metabolism , Animals , Cell Line , Colitis/chemically induced , Dextran Sulfate , Disease Models, Animal , Homeostasis/physiology , Humans , Metabolomics , Mice
7.
J Cell Physiol ; 234(1): 108-121, 2018 01.
Article in English | MEDLINE | ID: mdl-30076704

ABSTRACT

More than 40% of patients with luminal breast cancer treated with endocrine therapy agent tamoxifen demonstrate resistance. Emerging evidence suggests tumor initiating cells (TICs) and aberrant activation of Src and Akt signaling drive tamoxifen resistance and relapse. We previously demonstrated that aryl hydrocarbon receptor ligand aminoflavone (AF) inhibits the expression of TIC gene α6-integrin and disrupts mammospheres derived from tamoxifen-sensitive breast cancer cells. In the current study, we hypothesize that tamoxifen-resistant (TamR) cells exhibit higher levels of α6-integrin than tamoxifen-sensitive cells and that AF inhibits the growth of TamR cells by suppressing α6-integrin-Src-Akt signaling. In support of our hypothesis, TamR cells and associated mammospheres were found to exhibit elevated α6-integrin expression compared with their tamoxifen-sensitive counterparts. Furthermore, tumor sections from patients who relapsed on tamoxifen showed enhanced α6-integrin expression. Gene expression profiling from the TCGA database further revealed that basal-like breast cancer samples, known to be largely unresponsive to tamoxifen, demonstrated higher α6-integrin levels than luminal breast cancer samples. Importantly, AF reduced TamR cell viability and disrupted TamR mammospheres while concomitantly reducing α6-integrin messenger RNA and protein levels. In addition, AF and small interfering RNA against α6-integrin blocked tamoxifen-stimulated proliferation of TamR MCF-7 cells and further sensitized these cells to tamoxifen. Moreover, AF reduced Src and Akt signaling activation in TamR MCF-7 cells. Our findings suggest elevated α6-integrin expression is associated with tamoxifen resistance and AF suppresses α6-integrin-Src-Akt signaling activation to confer activity against TamR breast cancer.


Subject(s)
Breast Neoplasms/drug therapy , Flavonoids/pharmacology , Integrin alpha6/genetics , Receptors, Aryl Hydrocarbon/genetics , Breast Neoplasms/genetics , Breast Neoplasms/pathology , Drug Resistance, Neoplasm/genetics , Female , Gene Expression Profiling , Gene Expression Regulation, Neoplastic , Humans , Ligands , MCF-7 Cells , Neoplastic Stem Cells/drug effects , Oncogene Protein v-akt/genetics , Receptors, Aryl Hydrocarbon/antagonists & inhibitors , Signal Transduction , Tamoxifen/adverse effects , src-Family Kinases/genetics
8.
Gen Comp Endocrinol ; 247: 97-106, 2017 06 01.
Article in English | MEDLINE | ID: mdl-28137535

ABSTRACT

Because elevated glucocorticoid levels can impair reproduction, populations or species that engage in particularly valuable reproductive attempts may down-regulate the glucocorticoid stress response during reproduction (the brood value hypothesis). It is not clear, however, whether individuals rapidly modulate glucocorticoid responses based on shifting cues about the likelihood of reproductive success. By manipulating brood size to create broods that differed in potential value, we tested whether female barn swallows (Hirundo rustica) rapidly modulated the glucocorticoid stress response to promote investment in high-value broods, and whether nestling phenotype was influenced by treatment. Within-individual changes in female corticosterone, body mass, and measures of oxidative stress were unrelated to brood size treatment. Standard offspring provisioning rate did not differ across treatments; however, in the presence of a model predator, females raising enlarged broods maintained higher offspring feeding rates relative to control broods. Brood size did influence nestling phenotype. Nestlings from enlarged broods had lower body mass and higher baseline corticosterone than those from reduced broods. Finally, in adult females both baseline and stress-induced corticosterone were individually repeatable. Thus, while under moderately challenging environmental conditions brood size manipulations had context-dependent effects on parental investment, and influenced nestling phenotype, maternal glucocorticoid levels were not modulated based on brood value but were individually consistent features of phenotype during breeding.


Subject(s)
Glucocorticoids/pharmacology , Nesting Behavior , Swallows/physiology , Animals , Body Weight/drug effects , Female , Models, Biological , Phenotype
9.
Contemp Nurse ; 51(2-3): 220-31, 2015.
Article in English | MEDLINE | ID: mdl-26910100

ABSTRACT

AIM: To analyse the literature regarding the context and experiences of internationally qualified registered nurses, particularly Filipino and Indian nurses, who have transitioned to New Zealand. BACKGROUND: Internationally qualified nurses are a significant proportion of the nursing workforce in many developed countries including New Zealand. This is increasingly important as populations age, escalating demand for nurses. Understanding the internationally qualified nurse experience is required as this could influence migration in a competitive labour market. DESIGN: Examination of peer-reviewed research, policy and discussion documents, and technical reports. METHOD: A systematic literature search sought articles published between 2001 and 2014 using Google Scholar, CINAHL, and Medline. Articles were critically appraised for relevance, transferability, and methodological rigour. RESULTS: Fifty-one articles met inclusion criteria and demonstrate internationally qualified nurses face significant challenges transitioning into New Zealand. CONCLUSION: The internationally qualified nurse experience of transitioning into a new country is little researched and requires further investigation.


Subject(s)
Foreign Professional Personnel , Nursing Staff/supply & distribution , Humans , India/ethnology , New Zealand , Philippines/ethnology
10.
Proc Biol Sci ; 281(1790)2014 Sep 07.
Article in English | MEDLINE | ID: mdl-25056627

ABSTRACT

Glucocorticoid hormones (CORT) are predicted to promote adaptation to variable environments, yet little is known about the potential for CORT secretion patterns to respond to selection in free-living populations. We assessed the heritable variation underlying differences in hormonal phenotypes using a cross-foster experimental design with nestling North American barn swallows (Hirundo rustica erythrogaster). Using a bivariate animal model, we partitioned variance in baseline and stress-induced CORT concentrations into their additive genetic and rearing environment components and estimated their genetic correlation. Both baseline and stress-induced CORT were heritable with heritability of 0.152 and 0.343, respectively. We found that the variation in baseline CORT was best explained by rearing environment, whereas the variation in stress-induced CORT was contributed to by a combination of genetic and environmental factors. Further, we did not detect a genetic correlation between these two hormonal traits. Although rearing environment appears to play an important role in the secretion of both types of CORT, our results suggest that stress-induced CORT levels are underlain by greater additive genetic variance compared with baseline CORT levels. Accordingly, we infer that the glucocorticoid response to stress has a greater potential for evolutionary change in response to selection compared with baseline glucocorticoid secretion patterns.


Subject(s)
Glucocorticoids/blood , Stress, Physiological/physiology , Swallows/genetics , Swallows/physiology , Adaptation, Physiological/physiology , Animals , Animals, Newborn , Corticosterone/blood , Corticosterone/genetics , Female , Genotype , Glucocorticoids/genetics , Male , Swallows/growth & development
11.
Horm Behav ; 66(5): 812-9, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25461975

ABSTRACT

A fundamental element of how vertebrates respond to stressors is by rapidly elevating circulating glucocorticoid hormones. Individual variation in the magnitude of the glucocorticoid stress response has been linked with reproductive success and survival. But while the adaptive value of this response is believed to stem in part from changes in the expression of hormone-mediated behaviors, it is not clear how the behavior of stronger and weaker glucocorticoid responders differs during reproduction, or during exposure to ecologically relevant stressors. Here we report that in a population of barn swallows (Hirundo rustica erythrogaster) experiencing high rates of nest predation, circulating levels of corticosterone (the primary avian glucocorticoid) during exposure to a standardized stressor predict aspects of subsequent behavior and fitness. Individuals that mounted a stronger corticosterone stress response during the early reproductive period did not differ in clutch size, but fledged fewer offspring. Parents with higher stress-induced corticosterone during the early reproductive period later provisioned their nestlings at lower rates. Additionally, in the presence of a model predator stress-induced corticosterone was positively associated with the latency to return to the nest, but only among birds that were observed to return. Model comparisons revealed that stress-induced hormones were better predictors of the behavioral and fitness effects of exposure to transient, ecologically relevant stressors than baseline corticosterone. These findings are consistent with functional links between individual variation in the hormonal and behavioral response to stressors. If such links occur, then selection on the heritable components of the corticosterone stress response could promote adaptation to novel environments or predation regimes.


Subject(s)
Corticosterone/metabolism , Glucocorticoids/metabolism , Nesting Behavior/physiology , Reproduction/physiology , Stress, Psychological , Swallows/physiology , Animals , Energy Metabolism/physiology , Female , Individuality , Male , Predatory Behavior , Stress, Psychological/metabolism , Stress, Psychological/physiopathology
12.
JAMA Netw Open ; 7(8): e2426243, 2024 Aug 01.
Article in English | MEDLINE | ID: mdl-39110459

ABSTRACT

Importance: There are consistent data demonstrating that socioeconomic disadvantage is associated with risk of premature mortality, but research on the relationship between neighborhood socioeconomic factors and premature mortality is limited. Most studies evaluating the association between neighborhood socioeconomic status (SES) and mortality have used a single assessment of SES during middle to older adulthood, thereby not considering the contribution of early life neighborhood SES. Objective: To investigate the association of life course neighborhood SES and premature mortality. Design, Setting, and Participants: This cohort study included Black and White participants of the multicenter Atherosclerosis Risk in Communities Study, a multicenter study conducted in 4 US communities: Washington County, Maryland; Forsyth County, North Carolina; Jackson, Mississippi; and the northwestern suburbs of Minneapolis, Minnesota. Participants were followed up for a mean (SD) of 18.8 (5.7) years (1996-2020). Statistical analysis was performed from March 2023 through May 2024. Exposure: Participants' residential addresses during childhood, young adulthood, and middle adulthood were linked with US Census-based socioeconomic indicators to create summary neighborhood SES scores for each of these life epochs. Neighborhood SES scores were categorized into distribution-based tertiles. Main Outcomes and Measures: Premature death was defined as all-cause mortality occurring before age 75 years. Multivariable-adjusted Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% CIs. Results: Among 12 610 study participants, the mean (SD) age at baseline was 62.6 (5.6) years; 3181 (25.2%) were Black and 9429 (74.8%) were White; and 7222 (57.3%) were women. The lowest, compared with the highest tertile, of neighborhood SES score in middle adulthood was associated with higher risk of premature mortality (HR, 1.28; 95% CI, 1.07-1.54). Similar associations were observed for neighborhood SES in young adulthood among women (HR, 1.25; 95% CI, 1.00-1.56) and neighborhood SES in childhood among White participants (HR, 1.25; 95% CI, 1.01-1.56). Participants whose neighborhood SES remained low from young to middle adulthood had an increased premature mortality risk compared with those whose neighborhood SES remained high (HR, 1.25; 95% CI, 1.05-1.49). Conclusions and Relevance: In this study, low neighborhood SES was associated with premature mortality. The risk of premature mortality was greatest among individuals experiencing persistently low neighborhood SES from young to middle adulthood. Place-based interventions that target neighborhood social determinants of health should be designed from a life course perspective that accounts for early-life socioeconomic inequality.


Subject(s)
Mortality, Premature , Neighborhood Characteristics , Socioeconomic Factors , Adult , Aged , Female , Humans , Male , Middle Aged , Cohort Studies , Mortality, Premature/trends , Risk Factors , Social Class , Socioeconomic Disparities in Health , United States/epidemiology , Black or African American , White
13.
medRxiv ; 2024 Mar 19.
Article in English | MEDLINE | ID: mdl-39108508

ABSTRACT

Background: Breast cancer is comprised of distinct molecular subtypes. Studies have reported differences in risk factor associations with breast cancer subtypes, especially by tumor estrogen receptor (ER) status, but their consistency across racial and ethnic populations has not been comprehensively evaluated. Methods: We conducted a qualitative, scoping literature review using the Preferred Reporting Items for Systematic Reviews and Meta-analysis, extension for Scoping Reviews to investigate consistencies in associations between 18 breast cancer risk factors (reproductive, anthropometric, lifestyle, and medical history) and risk of ER-defined subtypes in women who self-identify as Asian, Black or African American, Hispanic or Latina, or White. We reviewed publications between January 1, 1990 and July 1, 2022. Etiologic heterogeneity evidence (convincing, suggestive, none, or inconclusive) was determined by expert consensus. Results: Publications per risk factor ranged from 14 (benign breast disease history) to 66 (parity). Publications were most abundant for White women, followed by Asian, Black or African American, and Hispanic or Latina women. Etiologic heterogeneity evidence was strongest for parity, followed by age at first birth, post-menopausal BMI, oral contraceptive use, and estrogen-only and combined menopausal hormone therapy. Evidence was limited for other risk factors. Findings were consistent across racial and ethnic groups, although the strength of evidence varied. Conclusion: The literature supports etiologic heterogeneity by ER for some established risk factors that are consistent across race and ethnicity groups. However, in non-White populations evidence is limited. Larger, more comparable data in diverse populations is needed to better characterize breast cancer etiologic heterogeneity.

14.
J Natl Cancer Inst ; 2024 Jul 17.
Article in English | MEDLINE | ID: mdl-39018167

ABSTRACT

BACKGROUND: Breast cancer is comprised of distinct molecular subtypes. Studies have reported differences in risk factor associations with breast cancer subtypes, especially by tumor estrogen receptor (ER) status, but their consistency across racial and ethnic populations has not been comprehensively evaluated. METHODS: We conducted a qualitative, scoping literature review using the Preferred Reporting Items for Systematic Reviews and Meta-analysis, extension for Scoping Reviews to investigate consistencies in associations between 18 breast cancer risk factors (reproductive, anthropometric, lifestyle, and medical history) and risk of ER-defined subtypes in women who self-identify as Asian, Black or African American, Hispanic or Latina, or White. We reviewed publications between January 1, 1990 and July 1, 2022. Etiologic heterogeneity evidence (convincing, suggestive, none, or inconclusive) was determined by expert consensus. RESULTS: Publications per risk factor ranged from 14 (benign breast disease history) to 66 (parity). Publications were most abundant for White women, followed by Asian, Black or African American, and Hispanic or Latina women. Etiologic heterogeneity evidence was strongest for parity, followed by age at first birth, post-menopausal BMI, oral contraceptive use, and estrogen-only and combined menopausal hormone therapy. Evidence was limited for other risk factors. Findings were consistent across racial and ethnic groups, although the strength of evidence varied. CONCLUSION: The literature supports etiologic heterogeneity by ER for some established risk factors that are consistent across race and ethnicity groups. However, in non-White populations evidence is limited. Larger, more comparable data in diverse populations is needed to better characterize breast cancer etiologic heterogeneity.

15.
Horm Behav ; 64(4): 665-72, 2013 Sep.
Article in English | MEDLINE | ID: mdl-24013040

ABSTRACT

Sexually selected traits confer greater reproductive benefits to individuals with more elaborate forms of the signal. However, whether these signals convey reliable information about the physiology underlying trait development remains unknown in many species. The steroid hormone corticosterone (CORT) mediates important physiological and behavioral processes during the vertebrate stress response, and CORT secretion itself can be modulated by melanocortins. Thus, sexually selected melanin-based plumage coloration could function as an honest signal of an individual's ability to respond to stressors. This hypothesis was tested in North American barn swallows, Hirundo rustica erythrogaster, where males with darker ventral plumage color exhibit higher phaeomelanin content and are more successful at reproduction. Because reproductive behavior occurs months after plumage signals are developed, we also addressed the potential temporal disconnect of physiological state during trait development and trait advertisement by analyzing three different measurements of CORT levels in adult males during the breeding season (trait advertisement) and in nestling males while they were growing their feathers (trait development). Variation in adult plumage color did not predict baseline or stress-induced CORT, or stress responsiveness. Likewise, there was no relationship between nestling plumage color and any of the CORT measurements, but heavier nestlings had significantly lower baseline CORT. Our finding that a predominantly phaeomelanin-based trait is unrelated to circulating CORT suggests that phaeomelanin and eumelanin signals may convey different physiological information, and highlights the need for further study on the biochemical links between the hypothalamic-pituitary-adrenal (HPA) axis and the production of different melanin-based pigments.


Subject(s)
Animal Communication , Corticosterone/blood , Feathers/chemistry , Melanins/analysis , Pigmentation/physiology , Stress, Psychological , Swallows/physiology , Animals , Animals, Newborn , Feathers/metabolism , Male , Melanins/metabolism , Restraint, Physical/psychology , Restraint, Physical/veterinary , Stress, Psychological/blood , Stress, Psychological/metabolism , Swallows/growth & development , Time Factors
16.
JAMA Netw Open ; 6(11): e2341651, 2023 Nov 01.
Article in English | MEDLINE | ID: mdl-37930698

ABSTRACT

Importance: The biological processes that underlie the association of neighborhood environment with chronic diseases, such as cancer, remain poorly understood. Objective: To determine whether differences in breast tissue DNA methylation are associated with neighborhood deprivation among Black and White women with breast cancer. Design, Setting, and Participants: This cross-sectional study collected breast tissue from women undergoing surgery for breast cancer between January 1, 1993, and December 31, 2003. Participants were recruited through the University of Maryland Medical Center, with additional collection sites at Baltimore-area hospitals. Data analysis was performed from March 1 through December 1, 2022. Exposure: Year 2000 census tract-level socioeconomic deprivation measured via neighborhood deprivation index (NDI) as a standardized score, with Black and White race being ascertained through self-report. Main Outcome and Measures: The primary outcome was tissue DNA methylation using genome-wide measurements. The secondary outcome was tissue gene expression. Results: Participants included 185 women with breast cancer (110 Black [59.5%], 75 White [40.5%]). Mean (SD) age at surgery was 56.0 (14.1) years. Neighborhood deprivation was higher for Black women than for White women (Mean [SD] NDI, 2.96 [3.03] for Black women and -0.54 [1.91] for White women; difference, -3.50; 95% CI, -4.22 to -2.79; P < .001). In unstratified analysis, 8 hypomethylated CpG sites were identified as associated with the NDI, including sites in 2 tumor suppressor genes, LRIG1 and WWOX. Moreover, expression of the 2 genes inversely correlated with neighborhood deprivation. In the race-stratified analysis, the negative correlation between the LRIG1 gene body CpG site cg26131019 and the NDI remained significant in Black women. A neighborhood deprivation-associated decrease in gene expression was also observed for LRIG1 and WWOX in tumors from Black women. Conclusions and Relevance: In this study, high neighborhood deprivation was associated with differences in tissue DNA methylation and gene expression among Black women. These findings suggest that continued investment in public health interventions and policy changes at the neighborhood level may help to remedy biological alterations that could make minoritized populations more susceptible to chronic diseases.


Subject(s)
Breast Neoplasms , DNA Methylation , Humans , Female , Middle Aged , Cross-Sectional Studies , DNA Methylation/genetics , Breast Neoplasms/genetics , Chronic Disease , Genes, Neoplasm
17.
Am J Bot ; 98(4): 669-79, 2011 Apr.
Article in English | MEDLINE | ID: mdl-21613166

ABSTRACT

PREMISE OF THE STUDY: Population genetic analyses provide information on the population context in which evolutionary processes operate and are important for understanding the evolution of geographically variable traits. Earlier studies showed that cone structure of lodgepole pine in the Rocky Mountains diverged among populations because of geographic variation in coevolutionary interactions involving mammalian and avian seed predators. Analyses of population genetic variation are needed to determine whether this divergence has arisen despite extensive gene flow and whether populations to the east and west of the Rocky Mountains have evolved convergent phenotypes independently. METHODS: We investigated genetic structuring across 22 stands of lodgepole pine in the central Rocky Mountains and in isolated peripheral populations that experience different seed predators and exhibit parallel divergence in cone traits using a set of nine simple sequence repeats and 235 AFLP loci. KEY RESULTS: Our analyses reveal high levels of genetic diversity within and low genetic differentiation among populations. Nonetheless, geographic and genetic distances were correlated, and isolated populations to the east and west of the Rocky Mountains had higher levels of differentiation than did populations in the central part of the range. CONCLUSIONS: These data indicate not only that adaptive divergence of cone traits across a geographic mosaic of coevolution has occurred despite minimal genetic differentiation, but also that isolated populations to the east and west of the Rocky Mountains have evolved distinctive cones independently and in parallel. The population structure quantified here will inform future research aimed at detecting genetic variants associated with divergent adaptive traits.


Subject(s)
Biological Evolution , DNA, Plant/analysis , Genetic Loci , Genetic Variation , Microsatellite Repeats , Phenotype , Pinus/genetics , Animals , Birds , Gene Flow , Genetics, Population , Mammals , United States
18.
Front Immunol ; 12: 653208, 2021.
Article in English | MEDLINE | ID: mdl-34149693

ABSTRACT

Tryptophan (Trp) is an essential amino acid primarily derived from the diet for use by the host for protein synthesis. The intestinal tract is lined with cells, both host and microbial, that uptake and metabolize Trp to also generate important signaling molecules. Serotonin (5-HT), kynurenine and its downstream metabolites, and to a lesser extent other neurotransmitters are generated by the host to signal onto host receptors and elicit physiological effects. 5-HT production by neurons in the CNS regulates sleep, mood, and appetite; 5-HT production in the intestinal tract by enterochromaffin cells regulates gastric motility and inflammation in the periphery. Kynurenine can signal onto the aryl hydrocarbon receptor (AHR) to elicit pleiotropic responses from several cell types including epithelial and immune cells, or can be further metabolized into bioactive molecules to influence neurodegenerative disease. There is a remarkable amount of cross-talk with the microbiome with regard to tryptophan metabolites as well. The gut microbiome can regulate the production of host tryptophan metabolites and can use dietary or recycled trp to generate bioactive metabolites themselves. Trp derivatives like indole are able to signal onto xenobiotic receptors, including AHR, to elicit tolerogenic effects. Here, we review studies that demonstrate that tryptophan represents a key intra-kingdom signaling molecule.


Subject(s)
Gastrointestinal Microbiome/physiology , Host Microbial Interactions/immunology , Signal Transduction/immunology , Tryptophan/metabolism , Animals , Humans , Kynurenine/metabolism , Metabolic Networks and Pathways/immunology , Models, Animal , Receptors, Aryl Hydrocarbon/metabolism , Serotonin/metabolism
19.
Sci Rep ; 11(1): 9247, 2021 04 29.
Article in English | MEDLINE | ID: mdl-33927264

ABSTRACT

Large-scale efforts to identify breast cancer (BC) risk alleles have historically taken place among women of European ancestry. Recently, there are new efforts to verify if these alleles increase risk in African American (AA) women as well. We investigated the effect of previously reported AA breast cancer and triple-negative breast cancer (TNBC) risk alleles in our African-enriched International Center for the Study of Breast Cancer Subtypes (ICSBCS) cohort. Using case-control, case-series and race-nested approaches, we report that the Duffy-null allele (rs2814778) is associated with TNBC risk (OR = 3.814, p = 0.001), specifically among AA individuals, after adjusting for self-indicated race and west African ancestry (OR = 3.368, p = 0.007). We have also validated the protective effect of the minor allele of the ANKLE1 missense variant rs2363956 among AA for TNBC (OR = 0.420, p = 0.005). Our results suggest that an ancestry-specific Duffy-null allele and differential prevalence of a polymorphic gene variant of ANKLE1 may play a role in TNBC breast cancer outcomes. These findings present opportunities for therapeutic potential and future studies to address race-specific differences in TNBC risk and disease outcome.


Subject(s)
Black People/genetics , Duffy Blood-Group System/genetics , Endonucleases/genetics , Receptors, Cell Surface/genetics , Triple Negative Breast Neoplasms/genetics , White People/genetics , Alleles , Biomarkers, Tumor/genetics , Case-Control Studies , Cohort Studies , Female , Genotype , Humans , Internationality , Middle Aged , Risk Factors , Triple Negative Breast Neoplasms/epidemiology , Triple Negative Breast Neoplasms/pathology
20.
Clin Cancer Res ; 26(8): 1905-1914, 2020 04 15.
Article in English | MEDLINE | ID: mdl-31911546

ABSTRACT

PURPOSE: Compared with their European American (EA) counterparts, African American (AA) women are more likely to die from breast cancer in the United States. This disparity is greatest in hormone receptor-positive subtypes. Here we uncover biological factors underlying this disparity by comparing functional expression and prognostic significance of master transcriptional regulators of luminal differentiation. EXPERIMENTAL DESIGN: Data and biospecimens from 262 AA and 293 EA patients diagnosed with breast cancer from 2001 to 2010 at a major medical center were analyzed by IHC for functional biomarkers of luminal differentiation, including estrogen receptor (ESR1) and its pioneer factors, FOXA1 and GATA3. Integrated comparison of protein levels with network-level gene expression analysis uncovered predictive correlations with race and survival. RESULTS: Univariate or multivariate HRs for overall survival, estimated from digital IHC scoring of nuclear antigen, show distinct differences in the magnitude and significance of these biomarkers to predict survival based on race: ESR1 [EA HR = 0.47; 95% confidence interval (CI), 0.31-0.72 and AA HR = 0.77; 95% CI, 0.48-1.18]; FOXA1 (EA HR = 0.38; 95% CI, 0.23-0.63 and AA HR = 0.53; 95% CI, 0.31-0.88), and GATA3 (EA HR = 0.36; 95% CI, 0.23-0.56; AA HR = 0.57; CI, 0.56-1.4). In addition, we identify genes in the downstream regulons of these biomarkers highly correlated with race and survival. CONCLUSIONS: Even within clinically homogeneous tumor groups, regulatory networks that drive mammary luminal differentiation reveal race-specific differences in their association with clinical outcome. Understanding these biomarkers and their downstream regulons will elucidate the intrinsic mechanisms that drive racial disparities in breast cancer survival.


Subject(s)
Black People/genetics , Breast Neoplasms/mortality , Estrogen Receptor alpha/metabolism , GATA3 Transcription Factor/metabolism , Gene Expression Regulation, Neoplastic , Hepatocyte Nuclear Factor 3-alpha/metabolism , White People/genetics , Biomarkers, Tumor/metabolism , Breast Neoplasms/ethnology , Breast Neoplasms/metabolism , Breast Neoplasms/pathology , Female , Health Status Disparities , Humans , Immunohistochemistry/methods , Middle Aged , Survival Rate , United States
SELECTION OF CITATIONS
SEARCH DETAIL