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1.
Cell ; 182(3): 563-577.e20, 2020 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-32615086

RESUMO

Adipose tissues dynamically remodel their cellular composition in response to external cues by stimulating beige adipocyte biogenesis; however, the developmental origin and pathways regulating this process remain insufficiently understood owing to adipose tissue heterogeneity. Here, we employed single-cell RNA-seq and identified a unique subset of adipocyte progenitor cells (APCs) that possessed the cell-intrinsic plasticity to give rise to beige fat. This beige APC population is proliferative and marked by cell-surface proteins, including PDGFRα, Sca1, and CD81. Notably, CD81 is not only a beige APC marker but also required for de novo beige fat biogenesis following cold exposure. CD81 forms a complex with αV/ß1 and αV/ß5 integrins and mediates the activation of integrin-FAK signaling in response to irisin. Importantly, CD81 loss causes diet-induced obesity, insulin resistance, and adipose tissue inflammation. These results suggest that CD81 functions as a key sensor of external inputs and controls beige APC proliferation and whole-body energy homeostasis.


Assuntos
Adipogenia/genética , Tecido Adiposo Bege/metabolismo , Metabolismo Energético/genética , Quinase 1 de Adesão Focal/metabolismo , Transdução de Sinais/genética , Células-Tronco/metabolismo , Tetraspanina 28/metabolismo , Adipócitos/metabolismo , Tecido Adiposo Bege/citologia , Tecido Adiposo Bege/crescimento & desenvolvimento , Tecido Adiposo Branco/metabolismo , Adulto , Animais , Ataxina-1/metabolismo , Feminino , Fibronectinas/farmacologia , Quinase 1 de Adesão Focal/genética , Humanos , Inflamação/genética , Inflamação/metabolismo , Resistência à Insulina/genética , Integrinas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pessoa de Meia-Idade , Obesidade/genética , Obesidade/metabolismo , RNA-Seq , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Transdução de Sinais/efeitos dos fármacos , Análise de Célula Única , Células-Tronco/citologia , Tetraspanina 28/genética
2.
Nat Immunol ; 20(9): 1220-1230, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31285626

RESUMO

Regulatory T (Treg) cells play a major role in the development of an immunosuppressive tumor microenvironment. The origin of intratumoral Treg cells and their relationship with peripheral blood Treg cells remain unclear. Treg cells consist of at least three functionally distinct subpopulations. Here we show that peripheral blood CD45RA-FOXP3hi Treg cells (Treg II cells) are phenotypically closest to intratumoral Treg cells, including in their expression of CCR8. Analyses of T cell antigen receptor repertoires further support the hypothesis that intratumoral Treg cells may originate primarily from peripheral blood Treg II cells. Moreover, the signaling responsiveness of peripheral blood Treg II cells to immunosuppressive, T helper type 1 (TH1) and T helper type 2 (TH2) cytokines reflects intratumoral immunosuppressive potential, and predicts future relapse in two independent cohorts of patients with breast cancer. Together, our findings give important insights into the relationship between peripheral blood Treg cells and intratumoral Treg cells, and highlight cytokine signaling responsiveness as a key determinant of intratumoral immunosuppressive potential and clinical outcome.


Assuntos
Neoplasias da Mama/patologia , Tolerância Imunológica/imunologia , Recidiva Local de Neoplasia/patologia , Linfócitos T Reguladores/imunologia , Citocinas/metabolismo , Feminino , Humanos , Pessoa de Meia-Idade , Receptores de Antígenos de Linfócitos T/imunologia , Transdução de Sinais/imunologia , Células Th1/imunologia , Células Th2/imunologia , Resultado do Tratamento , Microambiente Tumoral/imunologia
3.
Mol Cell ; 77(2): 279-293.e8, 2020 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-31784360

RESUMO

The genomes of mammalian neurons contain uniquely high levels of non-CG DNA methylation that can be bound by the Rett syndrome protein, MeCP2, to regulate gene expression. How patterns of non-CG methylation are established in neurons and the mechanism by which this methylation works with MeCP2 to control gene expression is unclear. Here, we find that genes repressed by MeCP2 are often located within megabase-scale regions of high non-CG methylation that correspond with topologically associating domains of chromatin folding. MeCP2 represses enhancers found in these domains that are enriched for non-CG and CG methylation, with the strongest repression occurring for enhancers located within MeCP2-repressed genes. These alterations in enhancer activity provide a mechanism for how MeCP2 disruption in disease can lead to widespread changes in gene expression. Hence, we find that DNA topology can shape non-CG DNA methylation across the genome to dictate MeCP2-mediated enhancer regulation in the brain.


Assuntos
Cromossomos/genética , Metilação de DNA/genética , Elementos Facilitadores Genéticos/genética , Proteína 2 de Ligação a Metil-CpG/genética , Proteínas Repressoras/genética , Animais , Encéfalo/fisiologia , Feminino , Regulação da Expressão Gênica/genética , Genoma/genética , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Ratos
4.
Proc Natl Acad Sci U S A ; 121(8): e2302259121, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38346204

RESUMO

Although evidence exists for a causal association between 25-hydroxyvitamin D (25(OH)D) serum levels, and multiple sclerosis (MS), the role of variation in vitamin D receptor (VDR) binding in MS is unknown. Here, we leveraged previously identified variants associated with allele imbalance in VDR binding (VDR-binding variant; VDR-BV) in ChIP-exo data from calcitriol-stimulated lymphoblastoid cell lines and 25(OH)D serum levels from genome-wide association studies to construct genetic instrumental variables (GIVs). GIVs are composed of one or more genetic variants that serve as proxies for exposures of interest. Here, GIVs for both VDR-BVs and 25(OH)D were used in a two-sample Mendelian Randomization study to investigate the relationship between VDR binding at a locus, 25(OH)D serum levels, and MS risk. Data for 13,598 MS cases and 38,887 controls of European ancestry from Kaiser Permanente Northern California, Swedish MS studies, and the UK Biobank were included. We estimated the association between each VDR-BV GIV and MS. Significant interaction between a VDR-BV GIV and a GIV for serum 25OH(D) was evidence for a causal association between VDR-BVs and MS unbiased by pleiotropy. We observed evidence for associations between two VDR-BVs (rs2881514, rs2531804) and MS after correction for multiple tests. There was evidence of interaction between rs2881514 and a 25(OH)D GIV, providing evidence of a causal association between rs2881514 and MS. This study is the first to demonstrate evidence that variation in VDR binding at a locus contributes to MS risk. Our results are relevant to other autoimmune diseases in which vitamin D plays a role.


Assuntos
Esclerose Múltipla , Humanos , Esclerose Múltipla/genética , Receptores de Calcitriol/genética , Receptores de Calcitriol/metabolismo , Alelos , Estudo de Associação Genômica Ampla , Vitamina D/metabolismo , Calcitriol , Polimorfismo de Nucleotídeo Único
5.
J Biol Chem ; 300(2): 105631, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38199575

RESUMO

Integrins are cell adhesion receptors that dimerize to mediate cell-cell interactions and regulate processes, including proliferation, inflammation, and tissue repair. The role of integrins in regulating insulin signaling is incompletely understood. We have previously shown that binding of the integrin ligand milk fat globule epidermal growth factor like 8 (MFGE8) to the αvß5 integrin promotes termination of insulin receptor signaling in mice. Upon ligation of MFGE8, integrin ß5 complexes with the insulin receptor beta (IRß) in skeletal muscle, resulting in dephosphorylation of IRß and reduction of insulin-stimulated glucose uptake. Here, we investigate the mechanism by which the interaction between ß5 and IRß impacts IRß phosphorylation status. We show in in vitro and in vivo in skeletal muscle in mice that antibody-mediated blockade of the ß5 integrin inhibits and recombinant MFGE8 promotes PTP1B binding to and dephosphorylation of IRß resulting in increased or reduced insulin-stimulated glucose uptake, respectively. The ß5-PTP1B complex is recruited by MFGE8 to IRß leading to termination of canonical insulin signaling. ß5 blockade enhances insulin-stimulated glucose uptake in wildtype but not Ptp1b KO mice indicating that PTP1B functions downstream of MFGE8 in modulating insulin receptor signaling. Furthermore, in a human cohort, we report serum MFGE8 levels correlate with indices of insulin resistance. These data provide mechanistic insights into the role of MFGE8 and ß5 in regulating insulin signaling.


Assuntos
Insulina , Receptor de Insulina , Animais , Humanos , Camundongos , Antígenos de Superfície/metabolismo , Glucose/metabolismo , Insulina/metabolismo , Cadeias beta de Integrinas , Proteínas do Leite/metabolismo , Receptor de Insulina/genética , Camundongos Endogâmicos C57BL , Masculino , Linhagem Celular
6.
Mol Microbiol ; 121(4): 727-741, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38183361

RESUMO

Adhesion to mucosal surfaces is a critical step in many bacterial and fungal infections. Here, using a mouse model of oral infection by the human fungal pathobiont Candida albicans, we report the identification of a novel regulator of C. albicans adhesion to the oral mucosa. The regulator is a member of the regulatory factor X (RFX) family of transcription factors, which control cellular processes ranging from genome integrity in model yeasts to tissue differentiation in vertebrates. Mice infected with the C. albicans rfx1 deletion mutant displayed increased fungal burden in tongues compared to animals infected with the reference strain. High-resolution imaging revealed RFX1 transcripts being expressed by C. albicans cells during infection. Concomitant with the increase in fungal burden, the rfx1 mutant elicited an enhanced innate immune response. Transcriptome analyses uncovered HWP1, a gene encoding an adhesion protein that mediates covalent attachment to buccal cells, as a major RFX1-regulated locus. Consistent with this result, we establish that C. albicans adhesion to oral cells is modulated by RFX1 in an HWP1-dependent manner. Our findings expand the repertoire of biological processes controlled by the RFX family and illustrate a mechanism whereby C. albicans can adjust adhesion to the oral epithelium.


Assuntos
Candida albicans , Proteínas Fúngicas , Fator Regulador X1 , Animais , Humanos , Candida albicans/genética , Epitélio/microbiologia , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Mucosa Bucal/microbiologia , Fator Regulador X1/genética , Fator Regulador X1/metabolismo
7.
Nature ; 574(7778): 404-408, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31578527

RESUMO

Over the past two decades efforts to control malaria have halved the number of cases globally, yet burdens remain high in much of Africa and the elimination of malaria has not been achieved even in areas where extreme reductions have been sustained, such as South Africa1,2. Studies seeking to understand the paradoxical persistence of malaria in areas in which surface water is absent for 3-8 months of the year have suggested that some species of Anopheles mosquito use long-distance migration3. Here we confirm this hypothesis through aerial sampling of mosquitoes at 40-290 m above ground level and provide-to our knowledge-the first evidence of windborne migration of African malaria vectors, and consequently of the pathogens that they transmit. Ten species, including the primary malaria vector Anopheles coluzzii, were identified among 235 anopheline mosquitoes that were captured during 617 nocturnal aerial collections in the Sahel of Mali. Notably, females accounted for more than 80% of all of the mosquitoes that we collected. Of these, 90% had taken a blood meal before their migration, which implies that pathogens are probably transported over long distances by migrating females. The likelihood of capturing Anopheles species increased with altitude (the height of the sampling panel above ground level) and during the wet seasons, but variation between years and localities was minimal. Simulated trajectories of mosquito flights indicated that there would be mean nightly displacements of up to 300 km for 9-h flight durations. Annually, the estimated numbers of mosquitoes at altitude that cross a 100-km line perpendicular to the prevailing wind direction included 81,000 Anopheles gambiae sensu stricto, 6 million A. coluzzii and 44 million Anopheles squamosus. These results provide compelling evidence that millions of malaria vectors that have previously fed on blood frequently migrate over hundreds of kilometres, and thus almost certainly spread malaria over these distances. The successful elimination of malaria may therefore depend on whether the sources of migrant vectors can be identified and controlled.


Assuntos
Migração Animal/fisiologia , Culicidae/fisiologia , Malária/transmissão , Mosquitos Vetores/fisiologia , Vento , África , Animais , Culicidae/parasitologia , Feminino , Mosquitos Vetores/parasitologia
8.
Ann Intern Med ; 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39222505

RESUMO

BACKGROUND: False-positive results on screening mammography may affect women's willingness to return for future screening. OBJECTIVE: To evaluate the association between screening mammography results and the probability of subsequent screening. DESIGN: Cohort study. SETTING: 177 facilities participating in the Breast Cancer Surveillance Consortium (BCSC). PATIENTS: 3 529 825 screening mammograms (3 184 482 true negatives and 345 343 false positives) performed from 2005 to 2017 among 1 053 672 women aged 40 to 73 years without a breast cancer diagnosis. MEASUREMENTS: Mammography results (true-negative result or false-positive recall with a recommendation for immediate additional imaging only, short-interval follow-up, or biopsy) from 1 or 2 screening mammograms. Absolute differences in the probability of returning for screening within 9 to 30 months of false-positive versus true-negative screening results were estimated, adjusting for race, ethnicity, age, time since last mammogram, BCSC registry, and clustering within women and facilities. RESULTS: Women were more likely to return after a true-negative result (76.9% [95% CI, 75.1% to 78.6%]) than after a false-positive recall for additional imaging only (adjusted absolute difference, -1.9 percentage points [CI, -3.1 to -0.7 percentage points]), short-interval follow-up (-15.9 percentage points [CI, -19.7 to -12.0 percentage points]), or biopsy (-10.0 percentage points [CI, -14.2 to -5.9 percentage points]). Asian and Hispanic/Latinx women had the largest decreases in the probability of returning after a false positive with a recommendation for short-interval follow-up (-20 to -25 percentage points) or biopsy (-13 to -14 percentage points) versus a true negative. Among women with 2 screening mammograms within 5 years, a false-positive result on the second was associated with a decreased probability of returning for a third regardless of the first screening result. LIMITATION: Women could receive care at non-BCSC facilities. CONCLUSION: Women were less likely to return to screening after false-positive mammography results, especially with recommendations for short-interval follow-up or biopsy, raising concerns about continued participation in routine screening among these women at increased breast cancer risk. PRIMARY FUNDING SOURCE: National Cancer Institute.

9.
10.
Am J Physiol Cell Physiol ; 326(1): C74-C88, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37982174

RESUMO

Diversity in the functional expression of ion channels contributes to the unique patterns of activity generated in visceral sensory A-type myelinated neurons versus C-type unmyelinated neurons in response to their natural stimuli. In the present study, Kv2 channels were identified as underlying a previously uncharacterized delayed rectifying potassium current expressed in both A- and C-type nodose ganglion neurons. Kv2.1 and 2.2 appear confined to the soma and initial segment of these sensory neurons; however, neither was identified in their central presynaptic terminals projecting onto relay neurons in the nucleus of the solitary tract (nTS). Kv2.1 and Kv2.2 were also not detected in the peripheral axons and sensory terminals in the aortic arch. Functionally, in nodose neuron somas, Kv2 currents exhibited frequency-dependent current inactivation and contributed to action potential repolarization in C-type neurons but not A-type neurons. Within the nTS, the block of Kv2 currents does not influence afferent presynaptic calcium influx or glutamate release in response to afferent activation, supporting our immunohistochemical observations. On the other hand, Kv2 channels contribute to membrane hyperpolarization and limit action potential discharge rate in second-order neurons. Together, these data demonstrate that Kv2 channels influence neuronal discharge within the vagal afferent-nTS circuit and indicate they may play a significant role in viscerosensory reflex function.NEW & NOTEWORTHY We demonstrate the expression and function of the voltage-gated delayed rectifier potassium channel Kv2 in vagal nodose neurons. Within sensory neurons, Kv2 channels limit the width of the broader C-type but not narrow A-type action potential. Within the nucleus of the solitary tract (nTS), the location of the vagal terminal field, Kv2 does not influence glutamate release. However, Kv2 limits the action potential discharge of nTS relay neurons. These data suggest a critical role for Kv2 in the vagal-nTS reflex arc.


Assuntos
Canais de Potássio de Abertura Dependente da Tensão da Membrana , Núcleo Solitário , Ratos , Animais , Núcleo Solitário/fisiologia , Ratos Sprague-Dawley , Neurônios/metabolismo , Glutamatos/metabolismo , Reflexo
11.
Biochemistry ; 63(10): 1246-1256, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38662574

RESUMO

Guanylate cyclase activating protein-5 (GCAP5) in zebrafish photoreceptors promotes the activation of membrane receptor retinal guanylate cyclase (GC-E). Previously, we showed the R22A mutation in GCAP5 (GCAP5R22A) abolishes dimerization of GCAP5 and activates GC-E by more than 3-fold compared to that of wild-type GCAP5 (GCAP5WT). Here, we present ITC, NMR, and functional analysis of GCAP5R22A to understand how R22A causes a decreased dimerization affinity and increased cyclase activation. ITC experiments reveal GCAP5R22A binds a total of 3 Ca2+, including two sites in the nanomolar range followed by a single micromolar site. The two nanomolar sites in GCAP5WT were not detected by ITC, suggesting that R22A may affect the binding of Ca2+ to these sites. The NMR-derived structure of GCAP5R22A is overall similar to that of GCAP5WT (RMSD = 2.3 Å), except for local differences near R22A (Q19, W20, Y21, and K23) and an altered orientation of the C-terminal helix near the N-terminal myristate. GCAP5R22A lacks an intermolecular salt bridge between R22 and D71 that may explain the weakened dimerization. We present a structural model of GCAP5 bound to GC-E in which the R22 side-chain contacts exposed hydrophobic residues in GC-E. Cyclase assays suggest that GC-E binds to GCAP5R22A with ∼25% higher affinity compared to GCAP5WT, consistent with more favorable hydrophobic contact by R22A that may help explain the increased cyclase activation.


Assuntos
Proteínas Ativadoras de Guanilato Ciclase , Guanilato Ciclase , Modelos Moleculares , Animais , Cálcio/metabolismo , Ativação Enzimática/genética , Guanilato Ciclase/genética , Guanilato Ciclase/metabolismo , Guanilato Ciclase/química , Proteínas Ativadoras de Guanilato Ciclase/metabolismo , Proteínas Ativadoras de Guanilato Ciclase/genética , Proteínas Ativadoras de Guanilato Ciclase/química , Mutação , Ressonância Magnética Nuclear Biomolecular , Conformação Proteica , Multimerização Proteica , Retina/metabolismo , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/química , Proteínas de Peixe-Zebra/metabolismo
12.
Breast Cancer Res ; 26(1): 73, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38685119

RESUMO

BACKGROUND: Following a breast cancer diagnosis, it is uncertain whether women's breast density knowledge influences their willingness to undergo pre-operative imaging to detect additional cancer in their breasts. We evaluated women's breast density knowledge and their willingness to delay treatment for pre-operative testing. METHODS: We surveyed women identified in the Breast Cancer Surveillance Consortium aged ≥ 18 years, with first breast cancer diagnosed within the prior 6-18 months, who had at least one breast density measurement within the 5 years prior to their diagnosis. We assessed women's breast density knowledge and correlates of willingness to delay treatment for 6 or more weeks for pre-operative imaging via logistic regression. RESULTS: Survey participation was 28.3% (969/3,430). Seventy-two percent (469/647) of women with dense and 11% (34/322) with non-dense breasts correctly knew their density (p < 0.001); 69% (665/969) of all women knew dense breasts make it harder to detect cancers on a mammogram; and 29% (285/969) were willing to delay treatment ≥ 6 weeks to undergo pre-operative imaging. Willingness to delay treatment did not differ by self-reported density (OR:0.99 for non-dense vs. dense; 95%CI: 0.50-1.96). Treatment with chemotherapy was associated with less willingness to delay treatment (OR:0.67; 95%CI: 0.46-0.96). Having previously delayed breast cancer treatment more than 3 months was associated with an increased willingness to delay treatment for pre-operative imaging (OR:2.18; 95%CI: 1.26-3.77). CONCLUSIONS: Understanding of personal breast density was not associated with willingness to delay treatment 6 or more weeks for pre-operative imaging, but aspects of a woman's treatment experience were. CLINICALTRIALS: GOV : NCT02980848 registered December 2, 2016.


Assuntos
Densidade da Mama , Neoplasias da Mama , Conhecimentos, Atitudes e Prática em Saúde , Mamografia , Tempo para o Tratamento , Humanos , Feminino , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/psicologia , Neoplasias da Mama/cirurgia , Neoplasias da Mama/diagnóstico , Pessoa de Meia-Idade , Mamografia/psicologia , Idoso , Adulto , Cuidados Pré-Operatórios , Inquéritos e Questionários , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Detecção Precoce de Câncer/psicologia
13.
Mol Biol Evol ; 40(12)2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37987559

RESUMO

Even in the genomics era, the phylogeny of Neotropical small felids comprised in the genus Leopardus remains contentious. We used whole-genome resequencing data to construct a time-calibrated consensus phylogeny of this group, quantify phylogenomic discordance, test for interspecies introgression, and assess patterns of genetic diversity and demographic history. We infer that the Leopardus radiation started in the Early Pliocene as an initial speciation burst, followed by another in its subgenus Oncifelis during the Early Pleistocene. Our findings challenge the long-held notion that ocelot (Leopardus pardalis) and margay (L. wiedii) are sister species and instead indicate that margay is most closely related to the enigmatic Andean cat (L. jacobita), whose whole-genome data are reported here for the first time. In addition, we found that the newly sampled Andean tiger cat (L. tigrinus pardinoides) population from Colombia associates closely with Central American tiger cats (L. tigrinus oncilla). Genealogical discordance was largely attributable to incomplete lineage sorting, yet was augmented by strong gene flow between ocelot and the ancestral branch of Oncifelis, as well as between Geoffroy's cat (L. geoffroyi) and southern tiger cat (L. guttulus). Contrasting demographic trajectories have led to disparate levels of current genomic diversity, with a nearly tenfold difference in heterozygosity between Andean cat and ocelot, spanning the entire range of variability found in extant felids. Our analyses improved our understanding of the speciation history and diversity patterns in this felid radiation, and highlight the benefits to phylogenomic inference of embracing the many heterogeneous signals scattered across the genome.


Assuntos
Felidae , Tigres , Animais , Filogenia , Felidae/genética , Evolução Biológica , Fluxo Gênico
14.
Am J Epidemiol ; 2024 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-39098823

RESUMO

Breast density is associated with risk of breast cancer (BC) diagnosis, impacting risk prediction tools and patient notification policies. Density affects mammography sensitivity and may influence screening intensity. Therefore, the observed association between density and BC diagnosis may not reflect the relationship between density and disease risk. We investigate the association between breast density and BC risk using data sourced from 33,542 women in the Breast Cancer Surveillance Consortium, 2000-2018. We estimated mammogram sensitivity and rates of screening mammography among dense (BI-RADS c, d) and non-dense (BI-RADS a, b) breasts. We used Kaplan-Meier estimates to summarize the relative risks of BC diagnosis (RRdx) by density and fit a natural history model to estimate the relative risks of BC onset (RRonset) given density-specific sensitivities. RRdx for dense versus non-dense breasts was 1.80 (95% CI 1.46 to 2.57). Based on estimated screening sensitivities of 0.88 and .78 for non-dense and dense breasts, respectively, RRonset was 1.73 (95% CI 1.43 to 2.25). Sensitivity analyses suggested higher breast density is robustly associated with increased risk of BC onset, similar in magnitude to the increased risk of BC diagnosis. These finding support laws requiring notifications to women with dense breasts of their increased BC risk.

15.
Cancer ; 130(4): 576-587, 2024 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-37886874

RESUMO

BACKGROUND: Racial disparities in outcomes exist in endometrial cancer (EC). The contribution of ancestry-based variations in germline pathogenic variants (gPVs) is unknown. METHODS: Germline assessment of ≥76 cancer predisposition genes was performed in patients with EC undergoing tumor-normal Memorial Sloan Kettering Cancer Center Integrated Mutation Profiling of Actionable Cancer Targets sequencing from January 1, 2015 through June 30, 2021. Self-reported race/ethnicity and Ashkenazi Jewish ancestry data classified patients into groups. Genetic ancestry was inferred from Memorial Sloan Kettering Cancer Center Integrated Mutation Profiling of Actionable Cancer Targets. Rates of gPV and genetic counseling were compared by ancestry. RESULTS: Among 1625 patients with EC, 216 (13%) had gPVs; 15 had >1 gPV. Rates of gPV varied by self-reported ancestry (Ashkenazi Jewish, 40/202 [20%]; Asian, 15/124 [12%]; Black/African American (AA), 12/171 [7.0%]; Hispanic, 15/124 [12%]; non-Hispanic (NH) White, 129/927 [14%]; missing, 5/77 [6.5%]; p = .009], with similar findings by genetic ancestry (p < .001). We observed a lower likelihood of gPVs in patients of Black/AA (odds ratio [OR], 0.44; 95% CI, 0.22-0.81) and African (AFR) ancestry (OR, 0.42; 95% CI, 0.18-0.85) and a higher likelihood in patients of Ashkenazi Jewish genetic ancestry (OR, 1.62; 95% CI; 1.11-2.34) compared with patients of non-Hispanic White/European ancestry, even after adjustment for age and molecular subtype. Somatic landscape influenced gPVs with lower rates of microsatellite instability-high tumors in patients of Black/AA and AFR ancestry. Among those with newly identified gPVs (n = 114), 102 (89%) were seen for genetic counseling, with lowest rates among Black/AA (75%) and AFR patients (67%). CONCLUSIONS: In those with EC, gPV and genetic counseling varied by ancestry, with lowest rates among Black/AA and AFR patients, potentially contributing to disparities in outcomes given implications for treatment and cancer prevention. PLAIN LANGUAGE SUMMARY: Black women with endometrial cancer do worse than White women, and there are many reasons for this disparity. Certain genetic changes from birth (mutations) can increase the risk of cancer, and it is unknown if rates of these changes are different between different ancestry groups. Genetic mutations in 1625 diverse women with endometrial cancer were studied and the lowest rates of mutations and genetic counseling were found in Black and African ancestry women. This could affect their treatment options as well as their families and may make disparities worse.


Assuntos
Neoplasias do Endométrio , Etnicidade , Grupos Raciais , Feminino , Humanos , Neoplasias do Endométrio/genética , Células Germinativas
16.
Ann Surg ; 280(4): 535-546, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38814074

RESUMO

OBJECTIVE: An expert panel made recommendations to optimize surgical education and training based on the effects of contemporary challenges. BACKGROUND: The inaugural Blue Ribbon Committee (BRC I) proposed sweeping recommendations for surgical education and training in 2004. In light of those findings, a second BRC (BRC II) was convened to make recommendations to optimize surgical training considering the current landscape in medical education. METHODS: BRC II was a panel of 67 experts selected on the basis of experience and leadership in surgical education and training. It was organized into subcommittees which met virtually over the course of a year. They developed recommendations, along with the Steering Committee, based on areas of focus and then presented them to the entire BRC II. The Delphi method was chosen to obtain consensus, defined as ≥80% agreement among the panel. Cronbach α was computed to assess the internal consistency of 3 Delphi rounds. RESULTS: Of the 50 recommendations, 31 obtained consensus in the following aspects of surgical training (# of consensus recommendation/# of proposed): Workforce (1/5); Medical Student Education (3/8); Work Life Integration (4/6); Resident Education (5/7); Goals, Structure, and Financing of Training (5/8); Education Support and Faculty Development (5/6); Research Training (7/9); and Educational Technology and Assessment (1/1). The internal consistency was good in Rounds 1 and 2 and acceptable in Round 3. CONCLUSIONS: BRC II used the Delphi approach to identify and recommend 31 priorities for surgical education in 2024. We advise establishing a multidisciplinary surgical educational group to oversee, monitor, and facilitate implementation of these recommendations.


Assuntos
Técnica Delphi , Cirurgia Geral , Estados Unidos , Humanos , Cirurgia Geral/educação , Educação de Pós-Graduação em Medicina/métodos
17.
Ann Surg ; 279(2): 231-239, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37916404

RESUMO

OBJECTIVE: To create a blueprint for surgical department leaders, academic institutions, and funding agencies to optimally support surgeon-scientists. BACKGROUND: Scientific contributions by surgeons have been transformative across many medical disciplines. Surgeon-scientists provide a distinct approach and mindset toward key scientific questions. However, lack of institutional support, pressure for increased clinical productivity, and growing administrative burden are major challenges for the surgeon-scientist, as is the time-consuming nature of surgical training and practice. METHODS: An American Surgical Association Research Sustainability Task Force was created to outline a blueprint for sustainable science in surgery. Leaders from top NIH-sponsored departments of surgery engaged in video and in-person meetings between January and April 2023. A strength, weakness, opportunities, threats analysis was performed, and workgroups focused on the roles of surgeons, the department and institutions, and funding agencies. RESULTS: Taskforce recommendations: (1) SURGEONS: Growth mindset : identifying research focus, long-term planning, patience/tenacity, team science, collaborations with disparate experts; Skill set : align skills and research, fill critical skill gaps, develop team leadership skills; DEPARTMENT OF SURGERY (DOS): (2) MENTORSHIP: Chair : mentor-mentee matching/regular meetings/accountability, review of junior faculty progress, mentorship training requirement, recognition of mentorship (eg, relative value unit equivalent, awards; Mentor: dedicated time, relevant scientific expertise, extramural funding, experience and/or trained as mentor, trusted advisor; Mentee : enthusiastic/eager, proactive, open to feedback, clear about goals; (3) FINANCIAL SUSTAINABILITY: diversification of research portfolio, identification of matching funding sources, departmental resource awards (eg, T-/P-grants), leveraging of institutional resources, negotiation of formalized/formulaic funds flow investment from academic medical center toward science, philanthropy; (4) STRUCTURAL/STRATEGIC SUPPORT: Structural: grants administrative support, biostats/bioinformatics support, clinical trial and research support, regulatory support, shared departmental laboratory space/equipment; Strategic: hiring diverse surgeon-scientist/scientists faculty across DOS, strategic faculty retention/ recruitment, philanthropy, career development support, progress tracking, grant writing support, DOS-wide research meetings, regular DOS strategic research planning; (5) COMMUNITY AND CULTURE: Community: right mix of faculty, connection surgeon with broad scientific community; Culture: building research infrastructure, financial support for research, projecting importance of research (awards, grand rounds, shoutouts); (6) THE ROLE OF INSTITUTIONS: Foundation: research space co-location, flexible start-up packages, courses/mock study section, awards, diverse institutional mentorship teams; Nurture: institutional infrastructure, funding (eg, endowed chairs), promotion friendly toward surgeon-scientists, surgeon-scientists in institutional leadership positions; Expectations: RVU target relief, salary gap funding, competitive starting salaries, longitudinal salary strategy; (7) THE ROLE OF FUNDING AGENCIES: change surgeon research training paradigm, offer alternate awards to K-awards, increasing salary cap to reflect market reality, time extension for surgeon early-stage investigator status, surgeon representation on study section, focused award strategies for professional societies/foundations. CONCLUSIONS: Authentic recommitment from surgeon leaders with intentional and ambitious actions from institutions, corporations, funders, and society is essential in order to reap the essential benefits of surgeon-scientists toward advancements of science.


Assuntos
Pesquisa Biomédica , Cirurgiões , Humanos , Estados Unidos , Mentores , Docentes , Centros Médicos Acadêmicos , Mobilidade Ocupacional , National Institutes of Health (U.S.)
18.
Oncologist ; 29(10): 859-869, 2024 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-39022993

RESUMO

INTRODUCTION: Personalized and tumor-informed circulating tumor DNA (ctDNA) testing is feasible and allows for molecular residual disease (MRD) identification in patients with pancreatic ductal adenocarcinoma (PDAC). METHODS: In this retrospective analysis of commercial cases from multiple US institutions, personalized, tumor-informed, whole-exome sequenced, and germline-controlled ctDNA levels were quantified and analyzed in patients with PDAC. Plasma samples (n = 1329) from 298 clinically validated patients were collected at diagnosis, perioperatively (MRD-window; within 2-12 weeks after surgery, before therapy), and during surveillance (>12 weeks post-surgery if no ACT or starting 4 weeks post-ACT) from November 2019 to March 2023. RESULTS: Of the initially diagnosed patients with stages I-III PDAC who went for resection, the median follow-up time from surgery was 13 months (range 0.1-214). Positive ctDNA detection rates were 29% (29/100) and 29.6% (45/152) during the MRD and surveillance windows, respectively. Positive ctDNA detection was significantly associated with shorter DFS within the MRD window (median DFS of 6.37 months for ctDNA-positive vs 33.31 months for ctDNA-negative patients; HR: 5.45, P < .0001) as well as during the surveillance period (median DFS: 11.40 months for ctDNA-positive vs NR for ctDNA-negative; HR: 12.38, P < .0001). Additionally, DFS was significantly better with KRAS wildtype status followed by KRASG12R (HR: 0.99, P = .97), KRASG12D (HR: 1.42, P = .194), and worse with KRASG12V (HR: 2.19, P = .002) status. In multivariate analysis, ctDNA detection at surveillance was found to be the most significant prognostic factor for recurrence (HR: 24.28, P < .001). CONCLUSIONS: Perioperative tumor-informed ctDNA detection in PDAC is feasible across all stages and is associated with patient survival outcomes.


Assuntos
DNA Tumoral Circulante , Neoplasias Pancreáticas , Humanos , DNA Tumoral Circulante/sangue , DNA Tumoral Circulante/genética , Masculino , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/cirurgia , Neoplasias Pancreáticas/sangue , Neoplasias Pancreáticas/patologia , Feminino , Idoso , Pessoa de Meia-Idade , Estudos Retrospectivos , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/mortalidade , Carcinoma Ductal Pancreático/sangue , Carcinoma Ductal Pancreático/cirurgia , Carcinoma Ductal Pancreático/patologia , Idoso de 80 Anos ou mais , Medicina de Precisão/métodos , Adulto , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/sangue , Adenocarcinoma/genética , Adenocarcinoma/mortalidade , Adenocarcinoma/sangue , Adenocarcinoma/cirurgia , Adenocarcinoma/patologia
19.
Radiology ; 312(2): e232380, 2024 08.
Artigo em Inglês | MEDLINE | ID: mdl-39105648

RESUMO

Background It is unclear whether breast US screening outcomes for women with dense breasts vary with levels of breast cancer risk. Purpose To evaluate US screening outcomes for female patients with dense breasts and different estimated breast cancer risk levels. Materials and Methods This retrospective observational study used data from US screening examinations in female patients with heterogeneously or extremely dense breasts conducted from January 2014 to October 2020 at 24 radiology facilities within three Breast Cancer Surveillance Consortium (BCSC) registries. The primary outcomes were the cancer detection rate, false-positive biopsy recommendation rate, and positive predictive value of biopsies performed (PPV3). Risk classification of participants was performed using established BCSC risk prediction models of estimated 6-year advanced breast cancer risk and 5-year invasive breast cancer risk. Differences in high- versus low- or average-risk categories were assessed using a generalized linear model. Results In total, 34 791 US screening examinations from 26 489 female patients (mean age at screening, 53.9 years ± 9.0 [SD]) were included. The overall cancer detection rate per 1000 examinations was 2.0 (95% CI: 1.6, 2.4) and was higher in patients with high versus low or average risk of 6-year advanced breast cancer (5.5 [95% CI: 3.5, 8.6] vs 1.3 [95% CI: 1.0, 1.8], respectively; P = .003). The overall false-positive biopsy recommendation rate per 1000 examinations was 29.6 (95% CI: 22.6, 38.6) and was higher in patients with high versus low or average 6-year advanced breast cancer risk (37.0 [95% CI: 28.2, 48.4] vs 28.1 [95% CI: 20.9, 37.8], respectively; P = .04). The overall PPV3 was 6.9% (67 of 975; 95% CI: 5.3, 8.9) and was higher in patients with high versus low or average 6-year advanced cancer risk (15.0% [15 of 100; 95% CI: 9.9, 22.2] vs 4.9% [30 of 615; 95% CI: 3.3, 7.2]; P = .01). Similar patterns in outcomes were observed by 5-year invasive breast cancer risk. Conclusion The cancer detection rate and PPV3 of supplemental US screening increased with the estimated risk of advanced and invasive breast cancer. © RSNA, 2024 Supplemental material is available for this article. See also the editorial by Helbich and Kapetas in this issue.


Assuntos
Densidade da Mama , Neoplasias da Mama , Detecção Precoce de Câncer , Ultrassonografia Mamária , Humanos , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Detecção Precoce de Câncer/métodos , Ultrassonografia Mamária/métodos , Medição de Risco , Adulto , Mama/diagnóstico por imagem , Mama/patologia , Estados Unidos , Idoso , Programas de Rastreamento/métodos , Sistema de Registros
20.
Drug Metab Dispos ; 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38811158

RESUMO

Evidence-based dose selection of drugs in pregnant women has been lacking due to challenges in studying maternal-fetal pharmacokinetics. Hence, many drugs are administered off-label during pregnancy based on data obtained from non-pregnant women. During pregnancy, drug transporters play an important role in drug disposition along with known gestational age-dependent changes in physiology and drug-metabolizing enzymes. In this review, as Dr. Qingcheng Mao's former and current lab members, we summarize the collective contributions of Dr. Mao, who lost his life to cancer, focusing on the role of drug transporters in drug disposition during pregnancy. Dr. Mao and his team initiated their research by characterizing the structure of Breast Cancer Resistance Protein [BCRP, ATP-Binding Cassette (ABC) G2]. Subsequently, they have made significant contributions to the understanding of the role of BCRP and other transporters, particularly P-glycoprotein (P-gp/ABCB1), in the exposure of pregnant women and their fetuses to various drugs, including nitrofurantoin, glyburide, buprenorphine, bupropion, tetrahydrocannabinol, and their metabolites. This review also highlights the gestation- and pregnancy-dependent transporter expression at the blood-brain and blood-placenta barriers in mice. Significance Statement Dr. Qingcheng Mao and his team have made significant contributions to the investigation of the role of efflux transporters, especially P-glycoprotein and breast cancer resistance protein, in maternal-fetal exposure to many xenobiotics: nitrofurantoin, glyburide, buprenorphine, bupropion, tetrahydrocannabinol and their metabolites. Studies of individual compounds and the expression of transporters during gestation and pregnancy have improved the understanding of maternal-fetal pharmacokinetics.

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