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1.
J Pharm Bioallied Sci ; 15(Suppl 1): S330-S332, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37654322

RESUMO

Introduction: The planning of effective orthodontic therapy greatly benefits from an understanding of the skeletal maturation and stage of growth of the patients seeking orthodontic treatment. However, the patient's various craniofacial structures have varying levels of growth potential. The patient is exposed to additional radiation when hand-wrist radiographs are regularly used to forecast growth. As an alternative, cervical vertebrae in the lateral cephalograph have been suggested. When arranging orthodontic treatment for growing children, it is important to take into account the pubertal growth spurt, which is a crucial time in therapy. Conclusion: Finding out how much growth a patient with skeletal discrepancy would experience during adolescence is one of the key goals of conducting a hand and wrist radiograph.

2.
Nat Commun ; 13(1): 3057, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35650195

RESUMO

Desmoplastic small round cell tumor (DSRCT) is an aggressive, usually incurable sarcoma subtype that predominantly occurs in post-pubertal young males. Recent evidence suggests that the androgen receptor (AR) can promote tumor progression in DSRCTs. However, the mechanism of AR-induced oncogenic stimulation remains undetermined. Herein, we demonstrate that enzalutamide and AR-directed antisense oligonucleotides (AR-ASO) block 5α-dihydrotestosterone (DHT)-induced DSRCT cell proliferation and reduce xenograft tumor burden. Gene expression analysis and chromatin immunoprecipitation sequencing (ChIP-seq) were performed to elucidate how AR signaling regulates cellular epigenetic programs. Remarkably, ChIP-seq revealed novel DSRCT-specific AR DNA binding sites adjacent to key oncogenic regulators, including WT1 (the C-terminal partner of the pathognomonic fusion protein) and FOXF1. Additionally, AR occupied enhancer sites that regulate the Wnt pathway, neural differentiation, and embryonic organ development, implicating AR in dysfunctional cell lineage commitment. Our findings have direct clinical implications given the widespread availability of FDA-approved androgen-targeted agents used for prostate cancer.


Assuntos
Antagonistas de Receptores de Andrógenos , Tumor Desmoplásico de Pequenas Células Redondas , Receptores Androgênicos , Antagonistas de Receptores de Andrógenos/farmacologia , Androgênios , Animais , Linhagem Celular Tumoral , Tumor Desmoplásico de Pequenas Células Redondas/genética , Humanos , Masculino , Oligonucleotídeos Antissenso/farmacologia , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
3.
Children (Basel) ; 9(4)2022 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-35455624

RESUMO

Standardized rounding checklists during multidisciplinary rounds (MDR) can reduce medical errors and decrease length of pediatric intensive care unit (PICU) and hospital stay. We added a standardized process for MDR in our oncologic PICU. Our study was a quality improvement initiative, utilizing a four-stage Plan-Do-Study-Act (PDSA) model to standardize MDR in our PICU over 3 months, from January 2020 to March 2020. We distributed surveys to PICU RNs to assess their understanding regarding communication during MDR. We created a standardized rounding checklist that addressed key elements during MDR. Safety event reports before and after implementation of our initiative were retrospectively reviewed to assess our initiative's impact on safety events. Our intervention increased standardization of PICU MDR from 0% to 70% over three months, from January 2020 to March 2020. We sustained a rate of zero for CLABSI, CAUTI, and VAP during the 12-month period prior to, during, and post-intervention. Implementation of a standardized rounding checklist may improve closed-loop communication amongst the healthcare team, facilitate dialogue between patients' families and the healthcare team, and reduce safety events. Additional staffing for resource RNs, who assist with high acuity patients, has also facilitated bedside RN participation in MDR, without interruptions in clinical care.

4.
Oncotarget ; 13: 521-533, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35284040

RESUMO

Osteosarcoma (OS) is a genetically diverse bone cancer that lacks a consistent targetable mutation. Recent studies suggest the IGF/PI3K/mTOR pathway and YAP/TAZ paralogs regulate cell fate and proliferation in response to biomechanical cues within the tumor microenvironment. How this occurs and their implication upon osteosarcoma survival, remains poorly understood. Here, we show that IGF-1R can translocate into the nucleus, where it may act as part of a transcription factor complex. To explore the relationship between YAP/TAZ and total and nuclear phosphorylated IGF-1R (pIGF-1R), we evaluated sequential tumor sections from a 37-patient tissue microarray by confocal microscopy. Next, we examined the relationship between stained markers, clinical disease characteristics, and patient outcomes. The nuclear to cytoplasmic ratios (N:C ratio) of YAP and TAZ strongly correlated with nuclear pIGF-1R (r = 0.522, p = 0.001 for each pair). Kaplan-Meier analyses indicated that nuclear pIGF-1R predicted poor overall survival, a finding confirmed in the Cox proportional hazards model. Though additional investigation in a larger prospective study will be required to validate the prognostic accuracy of these markers, our results may have broad implications for the new class of YAP, TAZ, AXL, or TEAD inhibitors that have reached early phase clinical trials this year.


Assuntos
Neoplasias Ósseas , Osteossarcoma , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Neoplasias Ósseas/metabolismo , Feminino , Humanos , Osteossarcoma/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Fator de Crescimento Placentário/metabolismo , Estudos Prospectivos , Serina-Treonina Quinases TOR/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Microambiente Tumoral
6.
J Clin Neurosci ; 89: 405-411, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34053821

RESUMO

H3K27M and H3.3G34R/V mutations have been identified in pediatric high-grade gliomas (pHGG), though extraneural metastases are rarely reported and poorly characterized. Three pHGG patients from two institutions were identified with extraneural metastasis, harboring histone mutations. Their clinical, imaging and molecular characteristics are reported here. A 17-year old female presented with supratentorial H3.3G34R-mutant glioma with metastatic osseous lesions in the spine, pelvis, bone marrow, pleural effusion and soft tissue of pelvis. Bone marrow biopsy and soft tissue of pelvis biopsy showed neoplastic cells positive for P53. A 20-year old female was diagnosed with H3F3A H3K27M-mutant thalamic glioma. She developed diffuse sclerotic osseous lesions. Biopsy of an osseous lesion was non-diagnostic. A 17-year old female presented with a H3F3A H3K27M-mutant diffuse midline glioma with diffuse spinal cord metastasis. She further developed multifocal chest lymphadenopathy, pleural effusions, and a soft tissue mass in the abdominal wall. The latter was positive for H3K27M mutation. We present the first case series of pHGG with H3F3A mutation and diffuse extraneural dissemination, describing their clinical and molecular profile.


Assuntos
Neoplasias Encefálicas/patologia , Glioma/patologia , Histonas/genética , Adolescente , Neoplasias Encefálicas/genética , Feminino , Glioma/genética , Humanos , Mutação , Metástase Neoplásica , Fenótipo , Tálamo/patologia , Adulto Jovem
7.
Cancer Gene Ther ; 28(12): 1325-1338, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33408328

RESUMO

Osteosarcoma (OS) is a molecularly heterogeneous, aggressive, poorly differentiated pediatric bone cancer that frequently spreads to the lung. Relatively little is known about phenotypic and epigenetic changes that promote lung metastases. To identify key drivers of metastasis, we studied human CCH-OS-D OS cells within a previously described rat acellular lung (ACL) model that preserves the native lung architecture, extracellular matrix, and capillary network. This system identified a subset of cells-termed derived circulating tumor cells (dCTCs)-that can migrate, intravasate, and spread within a bioreactor-perfused capillary network. Remarkably, dCTCs highly expressed epithelial-to-mesenchymal transition (EMT)-associated transcription factors (EMT-TFs), such as ZEB1, TWIST, and SOX9, which suggests that they undergo cellular reprogramming toward a less differentiated state by coopting the same epigenetic machinery used by carcinomas. Since YAP/TAZ and AXL tightly regulate the fate and plasticity of normal mesenchymal cells in response to microenvironmental cues, we explored whether these proteins contributed to OS metastatic potential using an isogenic pair of human OS cell lines that differ in AXL expression. We show that AXL inhibition significantly reduced the number of MG63.2 pulmonary metastases in murine models. Collectively, we present a laboratory-based method to detect and characterize a pure population of dCTCs, which provides a unique opportunity to study how OS cell fate and differentiation contributes to metastatic potential. Though the important step of clinical validation remains, our identification of AXL, ZEB1, and TWIST upregulation raises the tantalizing prospect that EMT-TF-directed therapies might expand the arsenal of therapies used to combat advanced-stage OS.


Assuntos
Osteossarcoma/genética , Proteínas Proto-Oncogênicas/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Proteínas de Sinalização YAP/metabolismo , Animais , Desdiferenciação Celular , Modelos Animais de Doenças , Humanos , Camundongos , Metástase Neoplásica , Osteossarcoma/patologia , Receptor Tirosina Quinase Axl
9.
Pediatr Neurosurg ; 55(4): 222-231, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32882694

RESUMO

INTRODUCTION: We report 2 cases of medulloblastoma maturing into gangliocytoma after receiving multimodal therapy. Here we present 2 cases of diagnosed medulloblastoma which on re-resection were noted to be gangliocytoma without heterogeneity, which is an extremely rare occurrence. CASE PRESENTATION: The first patient, an 11-year-old boy diagnosed with high-risk (non-WNT, non-SHH) medulloblastoma, was treated with near-total surgical resection followed by craniospinal radiation therapy with weekly vincristine. He then received maintenance chemotherapy with vincristine, cyclophosphamide, and cisplatin. On surveillance MR imaging studies residual tumor in the lateral aspect of the tumor bed was noted to be slowly growing, eliciting gross-total resection of the residual tumor. Histopathology showed benign gangliocytoma without residual medulloblastoma. The second patient, a 3-year-old girl, was diagnosed with medulloblastoma, desmoplastic nodular variant. She was initially treated with gross total resection and chemotherapy with etoposide, carboplatin, and high-dose methotrexate. At 4 months off therapy, she was noted to have local recurrence along the resection cavity. Second-line therapy was started with irinotecan and temozolomide, but MRI assessment during treatment showed further disease progression. She then received craniospinal radiation. Eleven months off therapy, further radiographic progression was noted, and the patient underwent second-look surgery, with pathology showing gangliocytoma and treatment-related gliosis. DISCUSSION/CONCLUSION: The maturation of medulloblastoma into a ganglion cell-rich lesion is very rare, with few well-characterized previous reports. Given the rare nature of this entity, it would be of great value to understand the process of posttreatment maturation and the genetic and treatment factors which contribute to this phenomenon.


Assuntos
Neoplasias Cerebelares , Ganglioneuroma , Meduloblastoma , Neoplasias Cerebelares/diagnóstico por imagem , Neoplasias Cerebelares/terapia , Criança , Pré-Escolar , Terapia Combinada , Feminino , Ganglioneuroma/diagnóstico por imagem , Ganglioneuroma/cirurgia , Humanos , Masculino , Meduloblastoma/diagnóstico por imagem , Meduloblastoma/terapia , Recidiva Local de Neoplasia , Vincristina
10.
Cancers (Basel) ; 12(7)2020 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-32630797

RESUMO

Background : Ten to fourteen percent of Ewing sarcoma (ES) study participants treated nationwide with IGF-1 receptor (IGF-1R)-targeted antibodies achieved tumor regression. Despite this success, low response rates and short response durations (approximately 7-weeks) have slowed the development of this therapy. Methods: We performed a meta-analysis of five phase-1b/2 ES-oriented trials that evaluated the anticancer activity of IGF-1R antibodies +/- mTOR inhibitors (mTORi). Our meta-analysis provided a head-to-head comparison of the clinical benefits of IGF-1R antibodies vs. the IGF-1R/mTOR-targeted combination. Available pretreatment clinical samples were semi-quantitatively scored using immunohistochemistry to detect proteins in the IGF-1R/PI3K/AKT/mTOR pathway linked to clinical response. Early PET/CT imaging, obtained within the first 2 weeks (median 10 days), were examined to determine if reduced FDG avidity was predictive of progression-free survival (PFS). Results: Among 56 ES patients treated at MD Anderson Cancer Center (MDACC) with IGF-1R antibodies, our analysis revealed a significant ~two-fold improvement in PFS that favored a combination of IGF-1R/mTORi therapy (1.6 vs. 3.3-months, p = 0.042). Low pIGF-1R in the pretreatment specimens was associated with treatment response. Reduced total-lesion glycolysis more accurately predicted the IGF-1R response than other previously reported radiological biomarkers. Conclusion: Synergistic drug combinations, and newly identified proteomic or radiological biomarkers of IGF-1R response, may be incorporated into future IGF-1R-related trials to improve the response rate in ES patients.

11.
Sarcoma ; 2020: 3498549, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33488267

RESUMO

Advances in molecular diagnostics have identified subsets of Ewing and Ewing-like sarcomas driven by variant translocations with unique biology. It is likely that patients with these tumours will have different clinical features and therapeutic outcomes. Nevertheless, the management of these patients both locally and within cooperative group trials depends on the local pathological diagnosis. It is not known what molecular diagnostic approaches are employed by local pathologists or if the exact translocation is commonly determined. In addition, it is not known what therapeutic approaches are employed for these patients or what cooperative trials are deemed appropriate for these patients by expert consensus. To answer these questions, we performed an international survey of oncologists and pathologists to better understand the diagnostic approaches used to identify variant translocations and the influence the findings have on therapy and clinical trial eligibility. An online survey was distributed to oncologists and pathologists primarily in North America. A total of 141 surveys were completed, representing a 28% response rate. The majority of respondents considered EWSR1-ETS gene family translocations (range 61-96%) to be Ewing sarcoma and would include them on the primary arm of a Ewing sarcoma clinical trial. There was a lack of consensus on how to classify and stratify BCOR-CCNB3, CIC-DUX4, and EWSR1+ with non-ETS partner fusions. Most respondents were either unsure how their institution tested, or their institution did not perform the test. In cases with atypical Ewing morphology, most respondents favoured additional fusion transcript testing. There is a lack of consensus regarding the classification and stratification of rare molecular subtypes in Ewing sarcoma. It is not clear how these alternative translocations have impacted outcomes for past clinical studies. This suggests a need for molecular confirmation of diagnoses and centralized or minimum standardization of testing for future trial enrolment.

12.
Acta Biomater ; 100: 38-51, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31542501

RESUMO

Current in vitro methods for assessing cancer biology and therapeutic response rely heavily on monolayer cell culture on hard, plastic surfaces that do not recapitulate essential elements of the tumor microenvironment. While a host of tumor models exist, most are not engineered to control the physical properties of the microenvironment and thus may not reflect the effects of mechanotransduction on tumor biology. Utilizing coaxial electrospinning, we developed three-dimensional (3D) tumor models with tunable mechanical properties in order to elucidate the effects of substrate stiffness and tissue architecture in osteosarcoma. Mechanical properties of coaxial electrospun meshes were characterized with a series of macroscale testing with uniaxial tensile testing and microscale testing utilizing atomic force microscopy on single fibers. Calculated moduli in our models ranged over three orders of magnitude in both macroscale and microscale testing. Osteosarcoma cells responded to decreasing substrate stiffness in 3D environments by increasing nuclear localization of Hippo pathway effectors, YAP and TAZ, while downregulating total YAP. Additionally, a downregulation of the IGF-1R/mTOR axis, the target of recent clinical trials in sarcoma, was observed in 3D models and heralded increased resistance to combination chemotherapy and IGF-1R/mTOR targeted agents compared to monolayer controls. In this study, we highlight the necessity of incorporating mechanical cues in cancer biology investigation and the complexity in mechanotransduction as a confluence of stiffness and culture architecture. Our models provide a versatile, mechanically variable substrate on which to study the effects of physical cues on the pathogenesis of tumors. STATEMENT OF SIGNIFICANCE: The tumor microenvironment plays a critical role in cancer pathogenesis. In this work, we engineered 3D, mechanically tunable, coaxial electrospun environments to determine the roles of the mechanical environment on osteosarcoma cell phenotype, morphology, and therapeutic response. We characterize the effects of varying macroscale and microscale stiffnesses in 3D environments on the localization and expression of the mechanoresponsive proteins, YAP and TAZ, and evaluate IGF-1R/mTOR pathway activation, a target of recent clinical trials in sarcoma. Increased nuclear YAP/TAZ was observed as stiffness in 3D was decreased. Downregulation of the IGF-1R/mTOR cascade in all 3D environments was observed. Our study highlights the complexity of mechanotransduction in 3D culture and represents a step towards controlling microenvironmental elements in in vitro cancer investigations.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Fenômenos Mecânicos , Mecanotransdução Celular , Modelos Biológicos , Osteossarcoma/metabolismo , Receptor IGF Tipo 1/metabolismo , Transativadores/metabolismo , Fatores de Transcrição/metabolismo , Neoplasias Ósseas/metabolismo , Linhagem Celular Tumoral , Regulação para Baixo , Módulo de Elasticidade , Gelatina/química , Humanos , Fenótipo , Poliésteres/química , Fatores de Transcrição SOXB1/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Resistência à Tração , Proteínas com Motivo de Ligação a PDZ com Coativador Transcricional , Microambiente Tumoral , Regulação para Cima , Proteínas de Sinalização YAP
13.
Bioengineering (Basel) ; 5(4)2018 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-30340362

RESUMO

Pediatric high-grade glioma (pHGG) and brainstem gliomas are some of the most challenging cancers to treat in children, with no effective therapies and 5-year survival at ~2% for diffuse intrinsic pontine glioma (DIPG) patients. The standard of care for pHGG as a whole remains surgery and radiation combined with chemotherapy, while radiation alone is standard treatment for DIPG. Unfortunately, these therapies lack specificity for malignant glioma cells and have few to no reliable biomarkers of efficacy. Recent discoveries have revealed that epigenetic disruption by highly conserved mutations in DNA-packaging histone proteins in pHGG, especially DIPG, contribute to the aggressive nature of these cancers. In this review we pose unanswered questions and address unexplored mechanisms in pre-clinical models and clinical trial data from pHGG patients. Particular focus will be paid towards therapeutics targeting chromatin modifiers and other epigenetic vulnerabilities that can be exploited for pHGG therapy. Further delineation of rational therapeutic combinations has strong potential to drive development of safe and efficacious treatments for pHGG patients.

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