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1.
Dalton Trans ; 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38874579

RESUMO

Carbene-metal-amide (CMA) complexes of gold, silver, and copper have been studied extensively for their photochemical/photocatalytic properties and as potential (pre-)catalysts in organic synthesis. Herein, the design, synthesis, and characterization of five bench-stable Au-, Ag-, and Cu-NHC complexes bearing the benzotriazolyl anion as an amide donor, are reported. All complexes are synthesized in a facile and straightforward manner, using mild conditions. The catalytic activity of the Ag and Cu complexes was studied in propargylamide cycloisomerization and carbonyl hydrosilylation reactions. Both CMA-catalyzed transformations proceed under mild conditions and are highly efficient for a range of propargylamides and carbonyl compounds, respectively, affording the desired corresponding products in good to excellent yields.

2.
Res Sq ; 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38853828

RESUMO

Aging is a prominent risk factor for Alzheimer's disease (AD), but the cellular mechanisms underlying neuronal phenotypes remain elusive. Both accumulation of amyloid plaques and neurofibrillary tangles in the brain1 and age-linked organelle deficits2-7 are proposed as causes of AD phenotypes but the relationship between these events is unclear. Here, we address this question using a transdifferentiated neuron (tNeuron) model directly from human dermal fibroblasts. Patient-derived tNeurons retain aging hallmarks and exhibit AD-linked deficits. Quantitative tNeuron proteomic analyses identify aging and AD-linked deficits in proteostasis and organelle homeostasis, particularly affecting endosome-lysosomal components. The proteostasis and lysosomal homeostasis deficits in aged tNeurons are exacerbated in sporadic and familial AD tNeurons, promoting constitutive lysosomal damage and defects in ESCRT-mediated repair. We find deficits in neuronal lysosomal homeostasis lead to inflammatory cytokine secretion, cell death and spontaneous development of Aß and phospho-Tau deposits. These proteotoxic inclusions co-localize with lysosomes and damage markers and resemble inclusions in brain tissue from AD patients and APP-transgenic mice. Supporting the centrality of lysosomal deficits driving AD phenotypes, lysosome-function enhancing compounds reduce AD-associated cytokine secretion and Aß deposits. We conclude that proteostasis and organelle deficits are upstream initiating factors leading to neuronal aging and AD phenotypes.

3.
Mol Cell Proteomics ; : 100801, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38880243

RESUMO

T cell activation is a complex biological process of naïve cells maturing into effector cells. Proteomic and phospho-proteomic approaches have provided critical insights into this process, yet it is not always clear how changes in individual proteins or phosphorylation sites have functional significance. Here, we developed the Phosphorylation Integrated Thermal Shift Assay (PITSA) that combines the measurement of protein or phosphorylation site abundance and thermal stability into a single TMT experiment and apply this method to study T cell activation. We quantified the abundance and thermal stability of over 7,500 proteins and 5,000 phosphorylation sites, and identified significant differences in chromatin-related, TCR signaling, DNA repair, and proliferative phosphoproteins. PITSA may be applied to a wide range of biological contexts to generate hypotheses as to which proteins or phosphorylation sites are functionally regulated in a given system, as well as the mechanisms by which this regulation may occur.

4.
bioRxiv ; 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38826417

RESUMO

Brain tissue injury caused by mild traumatic brain injury (mTBI) disproportionately concentrates in the midbrain, cerebellum, mesial temporal lobe, and the interface between cortex and white matter at sulcal depths 1-12. The bio-mechanical principles that explain why physical impacts to different parts of the skull translate to common foci of injury concentrated in specific brain structures are unknown. A general and longstanding idea, which has not to date been directly tested in humans, is that different brain regions are differentially susceptible to strain loading11,13-15. We use Magnetic Resonance Elastography (MRE) in healthy participants to develop whole-brain bio-mechanical vulnerability maps that independently define which regions of the brain exhibit disproportionate strain concentration. We then validate those vulnerability maps in a prospective cohort of mTBI patients, using diffusion MRI data collected at three cross-sectional timepoints after injury: acute, sub-acute, chronic. We show that regions that exhibit high strain, measured with MRE, are also the sites of greatest injury, as measured with diffusion MR in mTBI patients. This was the case in acute, subacute, and chronic subgroups of the mTBI cohort. Follow-on analyses decomposed the biomechanical cause of increased strain by showing it is caused jointly by disproportionately higher levels of energy arriving to 'high-strain' structures, as well as the inability of 'high strain' structures to effectively disperse that energy. These findings establish a causal mechanism that explains the anatomy of injury in mTBI based on in vivo rheological properties of the human brain.

5.
Int J Geriatr Psychiatry ; 39(6): e6105, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38822571

RESUMO

INTRODUCTION: Alcohol and substance use are increasing in older adults, many of whom have depression, and treatment in this context may be more hazardous. We assessed alcohol and other substance use patterns in older adults with treatment-resistant depression (TRD). We examined patient characteristics associated with higher alcohol consumption and examined the moderating effect of alcohol on the association between clinical variables and falls during antidepressant treatment. METHODS: This secondary and exploratory analysis used baseline clinical data and data on falls during treatment from a large randomized antidepressant trial in older adults with TRD (the OPTIMUM trial). Multivariable ordinal logistic regression was used to identify variables associated with higher alcohol use. An interaction model was used to evaluate the moderating effect of alcohol on falls during treatment. RESULTS: Of 687 participants, 51% acknowledged using alcohol: 10% were hazardous drinkers (AUDIT-10 score ≥5) and 41% were low-risk drinkers (score 1-4). Benzodiazepine use was seen in 24% of all participants and in 21% of drinkers. Use of other substances (mostly cannabis) was associated with alcohol consumption: it was seen in 5%, 9%, and 15% of abstainers, low-risk drinkers, and hazardous drinkers, respectively. Unexpectedly, use of other substances predicted increased risk of falls during antidepressant treatment only in abstainers. CONCLUSIONS: One-half of older adults with TRD in this study acknowledged using alcohol. Use of alcohol concurrent with benzodiazepine and other substances was common. Risks-such as falls-of using alcohol and other substances during antidepressant treatment needs further study.


Assuntos
Acidentes por Quedas , Consumo de Bebidas Alcoólicas , Antidepressivos , Transtorno Depressivo Resistente a Tratamento , Humanos , Masculino , Feminino , Idoso , Transtorno Depressivo Resistente a Tratamento/tratamento farmacológico , Acidentes por Quedas/estatística & dados numéricos , Antidepressivos/uso terapêutico , Pessoa de Meia-Idade , Modelos Logísticos , Idoso de 80 Anos ou mais , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Benzodiazepinas/uso terapêutico , Benzodiazepinas/efeitos adversos , Fatores de Risco
6.
Acta Med Philipp ; 58(10): 35-48, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38939423

RESUMO

Background: Based on the 2017-2020 annual report of the Department of Health-Antimicrobial Resistance Surveillance Program, significant resistance patterns have been observed for common disease-causing pathogens. In the hospital setting, antimicrobial stewardship programs have been implemented to optimize the use of antimicrobials. Drug utilization review studies provide essential feedback to improve prescribing and use of medications. Objectives: This study aimed to review drug utilization of monitored parenteral antimicrobials among patients admitted from January to December 2019. Methods: The study employed a retrospective, cross-sectional, descriptive research design. A retrospective chart review of drugs administered to patients was conducted. Results: A total of 821 patients charts met the inclusion criteria. The patients' ages ranged from 18 to 98 years old and 52% were females. General Internal Medicine practitioners (28%) were the top prescribers of monitored parenteral antimicrobials primarily for the management of moderate-risk community-acquired pneumonia (39%). They were mostly indicated for empirical treatment of infections (94%) and were given for an average of 5.73 days.Only 58% of the total cases had orders for culture and sensitivity testing. Of which, principally 47% had colony cultures. Blood (29%) and sputum (27%) were the most common specimens taken for culture and sensitivity testing. The microorganisms often isolated were Escherichia coli (19%), Klebsiella pneumoniae (18%), and Staphylococcus aureus (9%). In addition, extended-spectrum beta lactamase-producing gram-negative pathogens (4%) and methicillin-resistant S. aureus (1%) were also isolated. All the microorganisms isolated showed most resistance to ampicillin (81%) and most susceptibility to colistin (100%). There were drug therapy-related problems encountered. There was one case of an adverse drug reaction (0.1%) and two cases of contraindications (0.2%). Therapeutic duplication was also observed in 5% of the cases. Moreover, 39% had instances of drug-drug interactions.Piperacillin-tazobactam had the highest consumption (79.50 defined daily doses/1,000-patient days) among the monitored parenteral antimicrobials.Some prescriptions were deemed inappropriate upon evaluation. 12% of cases were inappropriate based on the justification indicator. As for the critical indicators, duration of therapy (78%) was the main reason. Only four components of the DUE criteria indicators have met or exceeded the established threshold level.The cost analysis indicated that the total actual cost of therapy with the monitored parenteral antimicrobials amounted to ₱17,645,601.73. Considering Department of Health National Antibiotic Guidelines recommendations, ideal total cost of treatment was ₱14,917,214.29. Potential cumulative cost savings of ₱2,728,387.44 could have been achieved for patients admitted last 2019. Conclusion: Consumption of piperacillin-tazobactam was relatively high as compared to the other monitored parenteral antimicrobials covered in this study. Physicians at the study site seldom prescribe monitored parenteral antimicrobials as recommended by the National Antibiotic Guidelines. This is evidenced in the incidence of inappropriate therapy regimens, with inapt duration of therapy as the leading explanation.From the patient's perspective, the main economic implication was on the direct medical costs, particularly the increased cost of the actual antimicrobial therapy prescribed to manage various infections. Adherence of physicians to the established guidelines and selection of the most cost-effective therapy could have resulted in considerable cost savings.

7.
Reg Anesth Pain Med ; 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38942427

RESUMO

BACKGROUND: Peer review represents a cornerstone of the scientific process, yet few studies have evaluated its association with scientific impact. The objective of this study is to assess the association of peer review scores with measures of impact for manuscripts submitted and ultimately published. METHODS: 3173 manuscripts submitted to Regional Anesthesia & Pain Medicine (RAPM) between August 2018 and October 2021 were analyzed, with those containing an abstract included. Articles were categorized by topic, type, acceptance status, author demographics and open-access status. Articles were scored based on means for the initial peer review where each reviewer's recommendation was assigned a number: 5 for 'accept', 3 for 'minor revision', 2 for 'major revision' and 0 for 'reject'. Articles were further classified by whether any reviewers recommended 'reject'. Rejected articles were analyzed to determine whether they were subsequently published in an indexed journal, and their citations were compared with those of accepted articles when the impact factor was <1.4 points lower than RAPM's 5.1 impact factor. The main outcome measure was the number of Clarivate citations within 2 years from publication. Secondary outcome measures were Google Scholar citations within 2 years and Altmetric score. RESULTS: 422 articles met inclusion criteria for analysis. There was no significant correlation between the number of Clarivate 2-year review citations and reviewer rating score (r=0.038, p=0.47), Google Scholar citations (r=0.053, p=0.31) or Altmetric score (p=0.38). There was no significant difference in 2-year Clarivate citations between accepted (median (IQR) 5 (2-10)) and rejected manuscripts published in journals with impact factors >3.7 (median 5 (2-7); p=0.39). Altmetric score was significantly higher for RAPM-published papers compared with RAPM-rejected ones (median 10 (5-17) vs 1 (0-2); p<0.001). CONCLUSIONS: Peer review rating scores were not associated with citations, though the impact of peer review on quality and association with other metrics remains unclear.

8.
Medicina (Kaunas) ; 60(6)2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38929564

RESUMO

The prevalence of skin aging and the request for effective treatments have driven dermatological research towards natural solutions. This study investigates the anti-aging efficacy of two bioactive natural polyphenols, Oleocanthal and Oleacein, in a skincare formulation. A single-blind, randomized clinical trial involved 70 participants, using a comprehensive exclusion criterion to ensure participant safety and study integrity. Participants applied the Oleocanthal and Oleacein 1% serum formulation twice daily for 30 days. The efficacy was objectively assessed using the VISIA® Skin Analysis System at baseline, after 15 days, and after 30 days. Results indicated significant wrinkle reduction in most groups. For women aged 45-79 years, the mean change was -33.91% (95% CI: -46.75% to -21.07%). For men aged 20-44 years, it was -51.93% (95% CI: -76.54% to -27.33%), and for men aged 45-79 years, it was -46.56% (95% CI: -58.32% to -34.81%). For women aged 20-44 years, the change was -25.68% (95% CI: -63.91% to 12.54%), not statistically significant. These findings highlight the potential of EVOO-derived polyphenols in anti-aging skincare, particularly for older adults. This research paves the way for further exploration into natural compounds in dermatology, particularly for aging skin management.


Assuntos
Aldeídos , Monoterpenos Ciclopentânicos , Fenóis , Envelhecimento da Pele , Humanos , Pessoa de Meia-Idade , Feminino , Masculino , Idoso , Adulto , Envelhecimento da Pele/efeitos dos fármacos , Método Simples-Cego , Fenóis/uso terapêutico , Fenóis/farmacologia
9.
J Affect Disord ; 361: 651-658, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38925306

RESUMO

BACKGROUND: The Patient Health Questionnaire (PHQ-9) and Montgomery-Asberg Depression Rating Scale (MADRS) are commonly used scales to measure depression severity in older adults. METHODS: We utilized data from the Optimizing Outcomes of Treatment-Resistant Depression in Older Adults (OPTIMUM) clinical trial to produce conversion tables relating PHQ-9 and MADRS total scores. We split the sample into training (N = 555) and validation samples (N = 187). Equipercentile linking was performed on the training sample to produce conversion tables for PHQ-9 and MADRS. We compared the original and estimated scores in the validation sample with Bland-Altman analysis. We compared the depression severity level using the original and estimated scores with Chi-square tests. RESULTS: The Bland-Altman analysis confirmed that differences between the original and estimated scores for at least 95 % of the sample fit within 1.96 standard deviations of the mean difference. Chi-square tests showed a significant difference in the proportion of participants at each depression severity category determined using the original and estimated scores. LIMITATIONS: The conversion tables should be used with caution when comparing depression severity at the individual level. CONCLUSIONS: Our conversion tables relating PHQ-9 and MADRS scores can be used to compare treatment outcomes using aggregate data in studies that only used one of these scales.

10.
J Neurosurg Pediatr ; : 1-13, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38905711

RESUMO

OBJECTIVE: Hydrocephalic macrocephaly can result in poor psychosocial development, positioning difficulties, skin breakdown, and poor cosmesis. Although reduction cranioplasty can address these sequelae, the postoperative outcomes, complications, and mortality risk of reduction cranioplasty are not well understood given the rarity of hydrocephalic macrocephaly. Therefore, the primary objective of this systematic review was to evaluate the surgical outcomes of reduction cranioplasty for the treatment of hydrocephalic macrocephaly. METHODS: A systematic review was performed using the PubMed, Scopus, and Web of Science databases while following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Two independent reviewers screened 350 studies; 27 studies reporting surgical outcomes on reduction cranioplasty for hydrocephalic macrocephaly met inclusion criteria. Data on study design, patient demographics, operative details, and surgical outcomes were collected. RESULTS: There were 65 reduction cranioplasties among the 27 included studies. Eighteen (66.7%) studies presented level V evidence, 7 (25.9%) presented level IV evidence, and 2 (7.4%) presented level III evidence. Following reduction cranioplasty, there was improvement in postoperative head positioning in 23 (85.2%) studies, improvement in postoperative cosmesis in 22 (81.5%) studies, and improvement in global postoperative neurological functioning in 20 (74.1%) studies. The median estimated blood loss was 633 mL (range 20-2600 mL). Shunt revisions were the most common complication, reported in 9 (47.4%) of the 19 studies assessing complications. Of the 65 patients, there was a mortality rate of 6.2% (n = 4). CONCLUSIONS: The majority of the included studies reported improvement in head size, head positioning, cranial cosmesis, and global neurological functioning following reduction cranioplasty for hydrocephalic macrocephaly. However, the prevalence of lower-level evidence, risk of blood loss, complications, and mortality indicates the need for a serious discussion of surgical indication, an experienced team, and thorough perioperative planning to perform these complex surgeries.

11.
Mol Cancer Ther ; 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38894678

RESUMO

Polo-like kinase 1 (PLK1) inhibitors have had limited antitumor efficacy as single agents, and a focus of current efforts is on combination therapies. We initially confirmed that the PLK1 specific inhibitor onvansertib (ONV) could enhance responses to a PARP inhibitor (olaparib) in prostate cancer xenografts. To identify more effective combinations we screened a library of bioactive compounds for efficacy in combination with ONV in LNCaP prostate cancer cells, which identified a series of compounds including multiple AKT inhibitors. We confirmed in vitro synergy between ONV and the AKT inhibitor ipatasertib (IPA) and found that the combination increased apoptosis. Mechanistic studies showed that ONV increased expression of the anti-apoptotic protein SURVIVIN, and that this was mitigated by IPA. Studies in three PTEN deficient prostate cancer xenograft models showed that co-treatment with IPA and ONV led to significant tumor growth inhibition compared to monotherapies. Together these in vitro and in vivo studies demonstrate that the efficacy of PLK1 antagonists can be enhanced by PARP or AKT inhibition, and support further development of these combination therapies.

12.
Semin Perinatol ; : 151928, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38937163

RESUMO

Critically ill newborns experience numerous painful procedures as part of lifesaving care in the Neonatal Intensive Care Unit. However, painful exposures in the neonatal period have been associated with alterations in brain maturation and poorer neurodevelopmental outcomes in childhood. The most frequently used medications for pain and sedation in the NICU are opioids, benzodiazepines and sucrose; these have also been associated with abnormalities in brain maturation and neurodevelopment making it challenging to know what the best approach is to treat neonatal pain. This article provides clinicians with an overview of how neonatal exposure to pain as well as analgesic and sedative medications impact brain maturation and neurodevelopmental outcomes in critically ill infants. We also highlight areas in need of future research to develop standardized neonatal pain monitoring and management strategies.

13.
J Reconstr Microsurg ; 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38838710

RESUMO

BACKGROUND: Decreased autologous flap vascular perfusion can lead to secondary procedures. Fluorescence angiography during surgery reduces the probability of repeat surgery but suffers from interpretation variability. Recently, the OnLume Avata System was developed, which evaluates real-time vascular perfusion in ambient light. This study aims to predict complications in autologous breast reconstruction using measures of relative intensity (RI) and relative area (RA). METHODS: Patients undergoing autologous breast reconstruction underwent intraoperative tissue perfusion assessment using the OnLume Avata System. Post-hoc image annotation was completed by labeling areas of the flap interpreted to be "Well Perfused," "Questionably Perfused," and "Under Perfused." RIs and RAs were calculated for the marked areas. Primary complications of interest were overall complication rate, fat and mastectomy skin flap necrosis, and surgical revision. Logistic regression was applied to determine the odds of developing a complication based on RI and RA for each image. RESULTS: A total of 25 patients (45 flaps) were included. In total, 17 patients (68%) developed at least one complication. Patients who developed any complication (p = 0.02) or underwent a surgical revision for complications (p = 0.02) had statistically lower RI of under-perfused portions of the flap. Patients with greater areas of under-perfused flap had a significantly higher risk of developing fat necrosis (odds ratio [OR]: 5.71, p = 0.03) and required a revision operation (OR: 1.10, p = 0.01). CONCLUSION: Image-based interpretation using the OnLume Avata System correlated with the risk of developing postoperative complications that standard fluorescence imaging systems may not appreciate. This information can benefit surgeons to improve perfusion assessment and intraoperative decision-making.

14.
Nanophotonics ; 13(14): 2453-2467, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38836102

RESUMO

We provide a simple method that enables readily acquired experimental data to be used to predict whether or not a candidate molecular material may exhibit strong coupling. Specifically, we explore the relationship between the hybrid molecular/photonic (polaritonic) states and the bulk optical response of the molecular material. For a given material, this approach enables a prediction of the maximum extent of strong coupling (vacuum Rabi splitting), irrespective of the nature of the confined light field. We provide formulae for the upper limit of the splitting in terms of the molar absorption coefficient, the attenuation coefficient, the extinction coefficient (imaginary part of the refractive index) and the absorbance. To illustrate this approach, we provide a number of examples, and we also discuss some of the limitations of our approach.

15.
Artigo em Inglês | MEDLINE | ID: mdl-38833710

RESUMO

OBJECTIVE: Determine the association of inflammatory biomarkers with clinical measures and recovery in participants with concussion. SETTING: Multicenter study in National Collegiate Athletic Association member institutions including military service academies. PARTICIPANTS: Four hundred twenty-two participants with acute concussion. DESIGN: Clinical visits and blood draws were completed preinjury and at multiple visits postconcussion (0-12 hours, 12-36 hours, and 36-60 hours postinjury). Clinical measures included Sport Concussion Assessment Tool (SCAT) symptom severity, Balance Error Scoring System, Standardized Assessment of Concussion (SAC), Brief Symptom Inventory-18 (BSI-18) scores, time to initiation of graduated return-to-play (RTP) protocol, and time to RTP. Interleukin (IL)-6, IL-10, IL-8, IL-1 receptor antagonist (RA), tumor necrosis factor (TNF), c-reactive protein, and vascular endothelial growth factor (VEGF) were measured in serum. Prespecified analyses focused on IL-6 and IL-1RA at 0 to 12 hours; exploratory analyses were conducted with false discovery rate correction. RESULTS: For prespecified analyses, IL-1RA at 0 to 12 hours in female participants was positively associated with more errors on the SAC (B(standard error, SE) = 0.58(0.27), P < .05) and worse SCAT symptom severity (B(SE) = 0.96(0.44), P < .05). For exploratory analyses, higher levels of IL-1RA at 12 to 36 hours were associated with higher global (B(SE) = 0.55(0.14), q < 0.01), depression (B(SE) = 0.45(0.10), q < 0.005), and somatization scores on the BSI (B(SE) = 0.46(0.12), q < 0.01) in participants with concussion; Higher TNF at 12 to 36 hours was associated with fewer errors on the SAC (B(SE) = - 0.46(0.14), q < 0.05). Subanalyses showed similar results for male participants and participants who were athletes. No associations were discovered in nonathlete cadets. Higher IL-8 at 0 to 12 hours was associated with slower RTP in female participants (OR = 14.47; 95% confidence interval, 2.96-70.66, q < 0.05); no other associations with recovery were observed. CONCLUSIONS: Peripheral inflammatory markers are associated with clinical symptoms following concussion and potentially represent one mechanism for psychological symptoms observed postinjury. Current results do not provide strong support for a potential prognostic role for these markers.

16.
Cancer Discov ; : OF1-OF9, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38867349

RESUMO

Juvenile myelomonocytic leukemia (JMML) is a hematologic malignancy of young children caused by mutations that increase Ras signaling output. Hematopoietic stem cell transplantation (HSCT) is a potentially curative treatment, but patients with relapsed or refractory (advanced) disease have dismal outcomes. This phase II trial evaluated the safety and efficacy of trametinib, an oral MEK1/2 inhibitor, in patients with advanced JMML. Ten infants and children were enrolled, and the objective response rate was 50%. Four patients with refractory disease proceeded to HSCT after receiving trametinib. Three additional patients completed all 12 cycles permitted on study and continue to receive off-protocol trametinib without HSCT. The remaining three patients had progressive disease with two demonstrating molecular evolution by the end of cycle 2. Transcriptomic and proteomic analyses provided novel insights into the mechanisms of response and resistance to trametinib in JMML. ClinicalTrials.gov Identifier: NCT03190915. Significance: Trametinib was safe and effective in young children with relapsed or refractory JMML, a lethal disease with poor survival rates. Seven of 10 patients completed the maximum 12 cycles of therapy or used trametinib as a bridge to HSCT and are alive with a median follow-up of 24 months.

17.
iScience ; 27(6): 110068, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38872973

RESUMO

Most cells in solid tumors are exposed to oxygen levels between 0.5% and 5%. We developed an approach that allows collection, processing, and evaluation of cancer and non-cancer cells under physioxia, while preventing exposure to ambient air. This aided comparison of baseline and drug-induced changes in signaling pathways under physioxia and ambient oxygen. Using tumor cells from transgenic models of breast cancer and cells from breast tissues of clinically breast cancer-free women, we demonstrate oxygen-dependent differences in cell preference for epidermal growth factor receptor (EGFR) or platelet-derived growth factor receptor beta (PDGFRß) signaling. Physioxia caused PDGFRß-mediated activation of AKT and extracellular regulated kinase (ERK) that reduced sensitivity to EGFR and phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA) inhibition and maintained PDGFRß+ epithelial-mesenchymal hybrid cells with potential cancer stem cell (CSC) properties. Cells in ambient air displayed differential EGFR activation and were more sensitive to targeted therapies. Our data emphasize the importance of oxygen considerations in preclinical cancer research to identify effective drug targets and develop combination therapy regimens.

20.
Front Oncol ; 14: 1191217, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38854737

RESUMO

Introduction: Approximately 50% of melanomas harbor an activating BRAFV600E mutation. Standard of care involves a combination of inhibitors targeting mutant BRAF and MEK1/2, the substrate for BRAF in the MAPK pathway. PTEN loss-of-function mutations occur in ~40% of BRAFV600E melanomas, resulting in increased PI3K/AKT activity that enhances resistance to BRAF/MEK combination inhibitor therapy. Methods: To compare the response of PTEN null to PTEN wild-type cells in an isogenic background, CRISPR/Cas9 was used to knock out PTEN in a melanoma cell line that harbors a BRAFV600E mutation. RNA sequencing, functional kinome analysis, and drug synergy screening were employed in the context of BRAF/MEK inhibition. Results: RNA sequencing and functional kinome analysis revealed that the loss of PTEN led to an induction of FOXD3 and an increase in expression of the FOXD3 target gene, ERBB3/HER3. Inhibition of BRAF and MEK1/2 in PTEN null, BRAFV600E cells dramatically induced the expression of ERBB3/HER3 relative to wild-type cells. A synergy screen of epigenetic modifiers and kinase inhibitors in combination with BRAFi/MEKi revealed that the pan ERBB/HER inhibitor, neratinib, could reverse the resistance observed in PTEN null, BRAFV600E cells. Conclusions: The findings indicate that PTEN null BRAFV600E melanoma exhibits increased reliance on ERBB/HER signaling when treated with clinically approved BRAFi/MEKi combinations. Future studies are warranted to test neratinib reversal of BRAFi/MEKi resistance in patient melanomas expressing ERBB3/HER3 in combination with its dimerization partner ERBB2/HER2.

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