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1.
Angew Chem Int Ed Engl ; 63(21): e202400781, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38527936

RESUMO

Short amphipathic peptides are capable of binding to transcriptional coactivators, often targeting the same binding surfaces as native transcriptional activation domains. However, they do so with modest affinity and generally poor selectivity, limiting their utility as synthetic modulators. Here we show that incorporation of a medium-chain, branched fatty acid to the N-terminus of one such heptameric lipopeptidomimetic (LPPM-8) increases the affinity for the coactivator Med25 >20-fold (Ki >100 µM to 4 µM), rendering it an effective inhibitor of Med25 protein-protein interactions (PPIs). The lipid structure, the peptide sequence, and the C-terminal functionalization of the lipopeptidomimetic each influence the structural propensity of LPPM-8 and its effectiveness as an inhibitor. LPPM-8 engages Med25 through interaction with the H2 face of its activator interaction domain and in doing so stabilizes full-length protein in the cellular proteome. Further, genes regulated by Med25-activator PPIs are inhibited in a cell model of triple-negative breast cancer. Thus, LPPM-8 is a useful tool for studying Med25 and mediator complex biology and the results indicate that lipopeptidomimetics may be a robust source of inhibitors for activator-coactivator complexes.


Assuntos
Complexo Mediador , Ativação Transcricional , Humanos , Complexo Mediador/metabolismo , Complexo Mediador/química , Peptídeos/química , Peptídeos/farmacologia , Peptídeos/metabolismo , Ligação Proteica , Ativação Transcricional/efeitos dos fármacos
2.
Oncogene ; 43(11): 763-775, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38310162

RESUMO

Both breast cancer and obesity can regulate epigenetic changes or be regulated by epigenetic changes. Due to the well-established link between obesity and an increased risk of developing breast cancer, understanding how obesity-mediated epigenetic changes affect breast cancer pathogenesis is critical. Researchers have described how obesity and breast cancer modulate the epigenome individually and synergistically. In this review, the epigenetic alterations that occur in obesity, including DNA methylation, histone, and chromatin modification, accelerated epigenetic age, carcinogenesis, metastasis, and tumor microenvironment modulation, are discussed. Delineating the relationship between obesity and epigenetic regulation is vital to furthering our understanding of breast cancer pathogenesis.


Assuntos
Neoplasias da Mama , Epigênese Genética , Humanos , Feminino , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Metilação de DNA , Histonas/metabolismo , Obesidade/complicações , Obesidade/genética , Microambiente Tumoral/genética
3.
Cancer Res ; 83(17): 2889-2907, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37335130

RESUMO

Triple-negative breast cancers (TNBC) tend to become invasive and metastatic at early stages in their development. Despite some treatment successes in early-stage localized TNBC, the rate of distant recurrence remains high, and long-term survival outcomes remain poor. In a search for new therapeutic targets for this disease, we observed that elevated expression of the serine/threonine kinase calcium/calmodulin (CaM)-dependent protein kinase kinase 2 (CaMKK2) is highly correlated with tumor invasiveness. In validation studies, genetic disruption of CaMKK2 expression or inhibition of its activity with small molecule inhibitors disrupted spontaneous metastatic outgrowth from primary tumors in murine xenograft models of TNBC. High-grade serous ovarian cancer (HGSOC), a high-risk, poor prognosis ovarian cancer subtype, shares many features with TNBC, and CaMKK2 inhibition effectively blocked metastatic progression in a validated xenograft model of this disease. Mechanistically, CaMKK2 increased the expression of the phosphodiesterase PDE1A, which hydrolyzed cyclic guanosine monophosphate (cGMP) to decrease the cGMP-dependent activity of protein kinase G1 (PKG1). Inhibition of PKG1 resulted in decreased phosphorylation of vasodilator-stimulated phosphoprotein (VASP), which in its hypophosphorylated state binds to and regulates F-actin assembly to facilitate cell movement. Together, these findings establish a targetable CaMKK2-PDE1A-PKG1-VASP signaling pathway that controls cancer cell motility and metastasis by impacting the actin cytoskeleton. Furthermore, it identifies CaMKK2 as a potential therapeutic target that can be exploited to restrict tumor invasiveness in patients diagnosed with early-stage TNBC or localized HGSOC. SIGNIFICANCE: CaMKK2 regulates actin cytoskeletal dynamics to promote tumor invasiveness and can be inhibited to suppress metastasis of breast and ovarian cancer, indicating CaMKK2 inhibition as a therapeutic strategy to arrest disease progression.


Assuntos
Neoplasias Ovarianas , Neoplasias de Mama Triplo Negativas , Animais , Feminino , Humanos , Camundongos , Actinas/metabolismo , Movimento Celular , Neoplasias Ovarianas/tratamento farmacológico , Proteínas Quinases
4.
bioRxiv ; 2023 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-37131673

RESUMO

Triple-negative breast cancers (TNBCs) tend to become highly invasive early during cancer development. Despite some successes in the initial treatment of patients diagnosed with early-stage localized TNBC, the rate of metastatic recurrence remains high with poor long-term survival outcomes. Here we show that elevated expression of the serine/threonine-kinase, Calcium/Calmodulin (CaM)-dependent protein kinase kinase-2 (CaMKK2), is highly correlated with tumor invasiveness. We determined that genetic disruption of CaMKK2 expression, or inhibition of its activity, disrupted spontaneous metastatic outgrowth from primary tumors in murine xenograft models of TNBC. High-grade serous ovarian cancer (HGSOC), a high-risk, poor-prognosis ovarian cancer subtype, shares many genetic features with TNBC, and importantly, CaMKK2 inhibition effectively blocked metastatic progression in a validated xenograft model of this disease. Probing the mechanistic links between CaMKK2 and metastasis we defined the elements of a new signaling pathway that impacts actin cytoskeletal dynamics in a manner which increases cell migration/invasion and metastasis. Notably, CaMKK2 increases the expression of the phosphodiesterase PDE1A which decreases the cGMP-dependent activity of protein kinase G1 (PKG1). This inhibition of PKG1 results in decreased phosphorylation of Vasodilator-Stimulated Phosphoprotein (VASP), which in its hypophosphorylated state binds to and regulates F-actin assembly to facilitate contraction/cell movement. Together, these data establish a targetable CaMKK2-PDE1A-PKG1-VASP signaling pathway that controls cancer cell motility and metastasis. Further, it credentials CaMKK2 as a therapeutic target that can be exploited in the discovery of agents for use in the neoadjuvant/adjuvant setting to restrict tumor invasiveness in patients diagnosed with early-stage TNBC or localized HGSOC.

5.
Pharmacol Res ; 192: 106757, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37023992

RESUMO

The liver is a major organ that is involved in essential biological functions such as digestion, nutrient storage, and detoxification. Furthermore, it is one of the most metabolically active organs with active roles in regulating carbohydrate, protein, and lipid metabolism. Hepatocellular carcinoma is a cancer of the liver that is associated in settings of chronic inflammation such as viral hepatitis, repeated toxin exposure, and fatty liver disease. Furthermore, liver cancer is the most common cause of death associated with cirrhosis and is the 3rd leading cause of global cancer deaths. LKB1 signaling has been demonstrated to play a role in regulating cellular metabolism under normal and nutrient deficient conditions. Furthermore, LKB1 signaling has been found to be involved in many cancers with most reports identifying LKB1 to have a tumor suppressive role. In this review, we use the KMPlotter database to correlate RNA levels of LKB1 signaling genes and hepatocellular carcinoma patient survival outcomes with the hopes of identifying potential biomarkers clinical usage. Based on our results STRADß, CAB39L, AMPKα, MARK2, SIK1, SIK2, BRSK1, BRSK2, and SNRK expression has a statistically significant impact on patient survival.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Quinases Proteína-Quinases Ativadas por AMP , Proteínas Quinases Ativadas por AMP/metabolismo , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo
6.
Ecology ; 104(6): e4044, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36976104

RESUMO

The Living Planet Index (LPI) is a crucial tool to track global biodiversity change, but necessarily sacrifices information to summarize thousands of population trends into a single communicable index. Evaluating when and how this information loss affects the LPI's performance is essential to ensure interpretations of the index reflect the truth as reliably as possible. Here, we evaluated the ability of the LPI to accurately and precisely capture trends of population change from uncertain data. We derived a mathematical analysis of uncertainty propagation in the LPI to track how measurement and process uncertainty may bias estimates of population growth rate trends, and to measure the overall uncertainty of the LPI. We demonstrated the propagation of uncertainty using simulated scenarios of declining, stable, or growing populations fluctuating independently, synchronously, or asynchronously, to assess the bias and uncertainty of the LPI in each scenario. We found that measurement and process uncertainty consistently pull the index below the expected true trend. Importantly, variability in the raw data scales up to draw the index further below the expected trend and to amplify its uncertainty, particularly when populations are small. These findings echo suggestions that a more complete assessment of the variability in population change trends, with particular attention to covarying populations, would enrich the LPI's already critical influence on conservation communication and decisions.


Assuntos
Conservação dos Recursos Naturais , Planetas , Incerteza , Biodiversidade , Crescimento Demográfico
8.
Front Biosci (Landmark Ed) ; 27(6): 196, 2022 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-35748272

RESUMO

Mitogen Activated Protein (MAP) kinases are a category of serine/threonine kinases that have been demonstrated to regulate intracellular events including stress responses, developmental processes, and cancer progression Although many MAP kinases have been extensively studied in various disease processes, MAP3K19 is an understudied kinase whose activities have been linked to lung disease and fibroblast development. In this manuscript, we use bioinformatics databases starBase, GEPIA, and KMPlotter, to establish baseline expressions of MAP3K19 in different tissue types and its correlation with patient survival in different cancers.


Assuntos
Proteínas Quinases Ativadas por Mitógeno , Neoplasias , Humanos , MAP Quinase Quinase Quinases , Sistema de Sinalização das MAP Quinases , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Neoplasias/genética , Fosforilação , Proteínas Serina-Treonina Quinases/genética
9.
Front Physiol ; 12: 751239, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34912237

RESUMO

Obesity rates are climbing, representing a confounding and contributing factor to many disease states, including cancer. With respect to breast cancer, obesity plays a prominent role in the etiology of this disease, with certain subtypes such as triple-negative breast cancer having a strong correlation between obesity and poor outcomes. Therefore, it is critical to examine the obesity-related alterations to the normal stroma and the tumor microenvironment (TME). Adipocytes and adipose stem cells (ASCs) are major components of breast tissue stroma that have essential functions in both physiological and pathological states, including energy storage and metabolic homeostasis, physical support of breast epithelial cells, and directing inflammatory and wound healing responses through secreted factors. However, these processes can become dysregulated in both metabolic disorders, such as obesity and also in the context of breast cancer. Given the well-established obesity-neoplasia axis, it is critical to understand how interactions between different cell types in the tumor microenvironment, including adipocytes and ASCs, govern carcinogenesis, tumorigenesis, and ultimately metastasis. ASCs and adipocytes have multifactorial roles in cancer progression; however, due to the plastic nature of these cells, they also have a role in regenerative medicine, making them promising tools for tissue engineering. At the physiological level, the interactions between obesity and breast cancer have been examined; here, we will delineate the mechanisms that regulate ASCs and adipocytes in these different contexts through interactions between cancer cells, immune cells, and other cell types present in the tumor microenvironment. We will define the current state of understanding of how adipocytes and ASCs contribute to tumor progression through their role in the tumor microenvironment and how this is altered in the context of obesity. We will also introduce recent developments in utilizing adipocytes and ASCs in novel approaches to breast reconstruction and regenerative medicine.

10.
J Vis Exp ; (170)2021 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-33970144

RESUMO

Breast cancer (BC) remains a leading cause of death for women. Despite more than $700 million invested in BC research annually, 97% of candidate BC drugs fail clinical trials. Therefore, new models are needed to improve our understanding of the disease. The NIH Microphysiological Systems (MPS) program was developed to improve the clinical translation of basic science discoveries and promising new therapeutic strategies. Here we present a method for generating MPS for breast cancers (BC-MPS). This model adapts a previously described approach of culturing primary human white adipose tissue (WAT) by sandwiching WAT between adipose-derived stem cell sheets (ASC)s. Novel aspects of our BC-MPS include seeding BC cells into non-diseased human breast tissue (HBT) containing native extracellular matrix, mature adipocytes, resident fibroblasts, and immune cells; and sandwiching the BC-HBT admixture between HBT-derived ASC sheets. The resulting BC-MPS is stable in culture ex vivo for at least 14 days. This model system contains multiple elements of the microenvironment that influence BC including adipocytes, stromal cells, immune cells, and the extracellular matrix. Thus BC-MPS can be used to study the interactions between BC and its microenvironment. We demonstrate the advantages of our BC-MPS by studying two BC behaviors known to influence cancer progression and metastasis: 1) BC motility and 2) BC-HBT metabolic crosstalk. While BC motility has previously been demonstrated using intravital imaging, BC-MPS allows for high-resolution time-lapse imaging using fluorescence microscopy over several days. Furthermore, while metabolic crosstalk was previously demonstrated using BC cells and murine pre-adipocytes differentiated into immature adipocytes, our BC-MPS model is the first system to demonstrate this crosstalk between primary human mammary adipocytes and BC cells in vitro.


Assuntos
Neoplasias da Mama/fisiopatologia , Mama/patologia , Diferenciação Celular , Feminino , Humanos , Microambiente Tumoral
11.
Cognition ; 210: 104587, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33508577

RESUMO

The label-feedback hypothesis (Lupyan, 2012) proposes that language modulates low- and high-level visual processing, such as priming visual object perception. Lupyan and Swingley (2012) found that repeating target names facilitates visual search, resulting in shorter response times (RTs) and higher accuracy. In the present investigation, we conceptually replicated and extended their study, using additional control conditions and recording eye movements during search. Our goal was to evaluate whether self-directed speech influences target locating (i.e. attentional guidance) or object perception (i.e., distractor rejection and target appreciation). In three experiments, during object search, people spoke target names, nonwords, irrelevant (absent) object names, or irrelevant (present) object names (all within-participants). Experiments 1 and 2 examined search RTs and accuracy: Speaking target names improved performance, without differences among the remaining conditions. Experiment 3 incorporated eye-tracking: Gaze fixation patterns suggested that language does not affect attentional guidance, but instead affects both distractor rejection and target appreciation. When search trials were conditionalized according to distractor fixations, language effects became more orderly: Search was fastest while people spoke target names, followed in linear order by the nonword, distractor-absent, and distractor-present conditions. We suggest that language affects template maintenance during search, allowing fluent differentiation of targets and distractors. Materials, data, and analyses can be retrieved here: https://osf.io/z9ex2/.


Assuntos
Atenção , Movimentos Oculares , Retroalimentação , Humanos , Tempo de Reação , Percepção Visual
12.
PeerJ ; 7: e7296, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31428536

RESUMO

Mediterranean maquis vegetation is highly biodiverse, but widespread grazing poses a challenge for management and conservation. We sampled woody and herbaceous plants separately on a limestone mountain with strong mesic-xeric gradients in Tunisia's Parc National de L'Ichkeul, assessed grazing pressure (on a scale of 1-3), and asked whether grazing had a significant effect on plant compositional abundance before and after controlling for environmental covariates. Sites on the more mesic lakeside face of the mountain were most compositionally unique, and forbs contributed most to the herbaceous beta-diversity on the mountain. We used variance partitioning to separate the collective and individual effects of the abiotic environment, grazing, human activity, and space on herbaceous and woody beta-diversity. However, the individual effect of grazing on overall plant community composition was confounded with space, due to the spatially autocorrelated grazing pressure on the mountain. Importantly, we found that herbaceous and woody communities responded differently to increasing levels of grazing intensity: herbaceous beta-diversity was highest between sites with no grazing pressure, while woody beta-diversity peaked under light grazing. Herbaceous community composition was sensitive to any intensity of grazing pressure, and biotic homogenization occured under moderate-to-high grazing pressure. On the other hand, woody community composition remained relatively similar under no to light grazing pressure, but differed under moderate-to-heavy grazing. Using a one-way permutational analysis of variance analysis, we showed that grazing had a significant effect when controlling for abiotic and spatial covariates. Our findings offer insight into the effects of grazing on maquis vegetation at Jebel Ichkeul, acting as a microcosm of similar conservation and management issues elsewhere in the Mediterranean. We suggest that a combination of monitoring and carefully controlled grazing may enhance plant diversity and maintain the region's biodiverse maquis vegetation, potentially maintaining a key climate refugium for vulnerable endemic species. Importantly, our study provides a useful baseline of the plant assemblages at Jebel Ichkeul with which to compare future vegetation changes.

13.
Clin Pediatr (Phila) ; 56(10): 912-919, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28436231

RESUMO

Urinary tract infections (UTIs) are the most common serious bacterial infection in children with significant morbidity with delayed diagnosis. Polymerase chain reaction (PCR) is very accurate in detecting bacteria and widely available, but has never been evaluated to detect UTIs in children. To assess the utility of PCR as a rapid diagnostic tool, we conducted a prospective cohort study of 193 urine samples from children younger than 36 months undergoing evaluation for UTI in the emergency department over a 10-month period. A quantification cycle (Cq) threshold of 26.15 identified all Escherichia coli positive samples with sensitivity and specificity of 100% and 99.5%, respectively (95% CI = 71.5%-100% and 97.9%-99.5%, respectively). A Cq threshold of 19.03 identified E coli infections >100 000 colony forming units/mL with sensitivity and specificity of 100% (95% CI = 72.2%-100% and 98.6%-100%, respectively). PCR is very accurate in diagnosing E coli UTIs in young children and could be useful as a rapid diagnostic tool.


Assuntos
Infecções por Escherichia coli/diagnóstico , Genótipo , Reação em Cadeia da Polimerase em Tempo Real/métodos , Infecções Urinárias/diagnóstico , Estudos de Coortes , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/urina , Feminino , Humanos , Lactente , Masculino , Estudos Prospectivos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Infecções Urinárias/urina
14.
Artigo em Inglês | MEDLINE | ID: mdl-28321299

RESUMO

Children with cancer and fever are at high risk for sepsis related death. Rapid antibiotic delivery (< 60 minutes) has been shown to reduce mortality. We compared patient outcomes and describe interventions from three separate quality improvement (QI) projects conducted in three United States (US) tertiary care pediatric emergency departments (EDs) with the shared aim to reduce time to antibiotic (TTA) to < 60 minutes in febrile pediatric oncology patients (Temperature > 38.0 C). A secondary objective was to identify interventions amenable to translation to other centers. We conducted a post project analysis of prospectively collected observational data from children < 18 years visiting these EDs during independently conducted QI projects. Comparisons were made pre to post intervention periods within each institution. All interventions were derived independently using QI methods by each institution. Successful as well as unsuccessful interventions were described and common interventions adopted by all sites identified. A total of 1032 ED patient visits were identified from the three projects. Improvement in median TTA delivery (min) pre to post intervention(s) was 118.5-57.0 at site 1, 163.0-97.5 at site 2, and 188.0-111.5 at site 3 (p<.001 all sites). The eight common interventions were 1) Triage application of topical anesthetic 2) Rapid room placement & triage 3) Resuscitation room placement of ill appearing children 4) Close proximity to central line equipment 5) Antibiotic administration before laboratory analyses 6) Consensus clinical practice guideline establishment 7) Family pre-ED education for fever and 8) Staff project updates. This core set of eight low cost, high yield QI interventions were developed independently by the three ED's which led to substantial reduction in time to antibiotic delivery in children with cancer presenting with fever. These interventions may inform future QI initiatives in other settings caring for febrile pediatric oncology patients.

15.
Cureus ; 9(12): e1949, 2017 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-29468104

RESUMO

Cerebellar stroke increases the risk of extensive physical disability and long-term institutionalization. The purpose of this case report is to describe the 14-month longitudinal rehabilitation management and outcomes from the intensive care unit, inpatient rehabilitation unit and outpatient care of a patient after cerebellar stroke. A goal of this case report is to provide rehabilitation clinicians with a long-term perspective and understanding of the course of recovery for a patient after cerebellar cerebrovascular accident or related injury. A 51-year-old healthy athletic female experienced acute bilateral cerebellar infarcts with subsequent craniotomy to remove infarcted areas. The patient had postoperative hemorrhages and hydrocephalus and was deemed to have a poor prognosis. Multimodal sensory stimulation and early mobility was performed until conventional neuromuscular reeducation interventions could be tolerated. Primary deficits included decreased proximal strength, whole body ataxia, vertical diplopia, dysphagia, difficulty communicating, and emotional lability. Fourteen months after the initial infarcts, the patient was able to reside in her own home with her husband, ambulate, and stand with assistance and perform most activities of daily living with standby or set-up assistance. This patient made significant progress toward safety and mobility and was able to return home despite the early discussion about a poor prognosis and a palliative care consultation. The complex, intensive course of rehabilitation elicited slow, steady, consistent gains. The patient's motivation and family involvement likely facilitated optimum outcomes.

16.
Pediatr Emerg Care ; 31(6): 419-21, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26035495

RESUMO

Pompe disease is a rare inherited disorder of glycogen metabolism. We present a case of a 9-month-old infant who presented to the emergency department with generalized hypotonia and respiratory distress and was found to have Pompe disease. In this article, we will review the differential diagnosis of hypotonia in the infant, presentations of hypotonia that are relevant to the emergency department physician, as well as the diagnosis, management, and prognosis of Pompe disease.


Assuntos
Doença de Depósito de Glicogênio Tipo II/diagnóstico , Biópsia , Botulismo/diagnóstico , Deficiências do Desenvolvimento/etiologia , Diagnóstico Diferencial , Doenças em Gêmeos , Eletromiografia , Glucana 1,4-alfa-Glucosidase/genética , Humanos , Lactente , Masculino , Hipotonia Muscular/etiologia , Músculo Esquelético/patologia , Prognóstico , Transtornos Respiratórios/etiologia , Traqueostomia , Gêmeos Dizigóticos
17.
N C Med J ; 73(4): 297-300, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23033722

RESUMO

Health impact assessment (HIA), a systematic way of incorporating health considerations into the public policy decision-making process, has been set into motion in North Carolina. The state's public health and planning fields are well positioned to become leaders of HIA and should prepare to take proactive measures to promote health in their communities.


Assuntos
Planejamento em Saúde Comunitária/organização & administração , Tomada de Decisões Gerenciais , Promoção da Saúde/organização & administração , Relações Interinstitucionais , Administração em Saúde Pública/métodos , Política Pública , Diretrizes para o Planejamento em Saúde , Humanos , North Carolina
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