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Despite the advances in imaging, surgery and radiotherapy, the majority of patients with brainstem gliomas die within 2 years after initial diagnosis. Factors that contribute to the dismal prognosis of these patients include the infiltrative nature and anatomic location in an eloquent area of the brain, which prevents total surgical resection and the presence of the blood-brain barrier (BBB), which reduces the distribution of systemically administered agents. The development of new therapeutic approaches which can circumvent the BBB is a potential path to improve outcomes for these children. Convection-enhanced delivery (CED) and intranasal delivery (IND) are strategies that permit direct drug delivery into the central nervous system and are an alternative to intravenous injection (IV). We treated rats bearing human brainstem tumor xenografts with nanoliposomal irinotecan (CPT-11) using CED, IND, and IV. A single treatment of CED irinotecan had a similar effect on overall survival as multiple treatments by IV route. IND CPT-11 showed significantly increased survival of animals with brainstem tumors, and demonstrated the promise of this non-invasive approach of drug delivery bypassing the BBB when combined with nanoliposomal chemotherapy. Our results indicated that using CED and IND of nanoliposomal therapy increase likelihood of practical therapeutic approach for the treatment of brainstem gliomas.
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Neoplasias del Tronco Encefálico/tratamiento farmacológico , Irinotecán/administración & dosificación , Inhibidores de Topoisomerasa I/administración & dosificación , Administración Intranasal , Animales , Neoplasias del Tronco Encefálico/mortalidad , Línea Celular Tumoral , Convección , Portadores de Fármacos , Humanos , Irinotecán/farmacocinética , Liposomas , Masculino , Nanoestructuras , Ratas , Inhibidores de Topoisomerasa I/farmacocinética , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Whether profound carcinoembryonic antigen (CEA) elevations, such as > 20 times the upper limit of normal, are of diagnostic use remain unknown. Herein, we present a case of a 55-year-old female with profound serum CEA elevation and multiple pelvic masses but with no evidence of a primary gastrointestinal tumor following upper endoscopy and colonoscopy. Subsequent immunostaining of resected pelvic masses confirmed adenocarcinoma of colorectal origin. This case report highlights the possible diagnostic role of profound CEA elevation, particularly in cases of unknown primary tumors.
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PURPOSE: Radiotherapy (RT) has long been and remains the only treatment option for diffuse intrinsic pontine glioma (DIPG). However, all patients show evidence of disease progression within months of completing RT. No further clinical benefit has been achieved using alternative radiation strategies. Here, we tested the hypothesis that histone demethylase inhibition by GSK-J4 enhances radiation-induced DNA damage, making it a potential radiosensitizer in the treatment of DIPG.Experimental Design: We evaluated the effects of GSK-J4 on genes associated with DNA double-strand break (DSB) repair in DIPG cells by RNA sequence, ATAC sequence, and quantitative real-time PCR. Radiation-induced DNA DSB repair was analyzed by immunocytochemistry of DSB markers γH2AX and 53BP1, DNA-repair assay, and cell-cycle distribution. Clonogenic survival assay was used to determine the effect of GSK-J4 on radiation response of DIPG cells. In vivo response to radiation monotherapy and combination therapy of RT and GSK-J4 was evaluated in patient-derived DIPG xenografts. RESULTS: GSK-J4 significantly reduced the expression of DNA DSB repair genes and DNA accessibility in DIPG cells. GSK-J4 sustained high levels of γH2AX and 53BP1 in irradiated DIPG cells, thereby inhibiting DNA DSB repair through homologous recombination pathway. GSK-J4 reduced clonogenic survival and enhanced radiation effect in DIPG cells. In vivo studies revealed increased survival of animals treated with combination therapy of RT and GSK-J4 compared with either monotherapy. CONCLUSIONS: Together, these results highlight GSK-J4 as a potential radiosensitizer and provide a rationale for developing combination therapy with radiation in the treatment of DIPG.
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Glioma Pontino Intrínseco Difuso/metabolismo , Histona Demetilasas/antagonistas & inhibidores , Histona Demetilasas/metabolismo , Tolerancia a Radiación , Fármacos Sensibilizantes a Radiaciones/farmacología , Animales , Benzazepinas/farmacología , Línea Celular Tumoral , Daño del ADN , Reparación del ADN/efectos de los fármacos , Glioma Pontino Intrínseco Difuso/genética , Glioma Pontino Intrínseco Difuso/mortalidad , Glioma Pontino Intrínseco Difuso/radioterapia , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Relación Dosis-Respuesta en la Radiación , Femenino , Recombinación Homóloga , Humanos , Ratones , Pronóstico , Pirimidinas/farmacología , Tolerancia a Radiación/genética , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
The lysine methyltransferase KMT2C (also known as MLL3), a subunit of the COMPASS complex, implements monomethylation of Lys4 on histone H3 (H3K4) at gene enhancers. KMT2C (hereafter referred to as MLL3) frequently incurs point mutations across a range of human tumor types, but precisely how these lesions alter MLL3 function and contribute to oncogenesis is unclear. Here we report a cancer mutational hotspot in MLL3 within the region encoding its plant homeodomain (PHD) repeats and demonstrate that this domain mediates association of MLL3 with the histone H2A deubiquitinase and tumor suppressor BAP1. Cancer-associated mutations in the sequence encoding the MLL3 PHD repeats disrupt the interaction between MLL3 and BAP1 and correlate with poor patient survival. Cancer cells that had PHD-associated MLL3 mutations or lacked BAP1 showed reduced recruitment of MLL3 and the H3K27 demethylase KDM6A (also known as UTX) to gene enhancers. As a result, inhibition of the H3K27 methyltransferase activity of the Polycomb repressive complex 2 (PRC2) in tumor cells harboring BAP1 or MLL3 mutations restored normal gene expression patterns and impaired cell proliferation in vivo. This study provides mechanistic insight into the oncogenic effects of PHD-associated mutations in MLL3 and suggests that restoration of a balanced state of Polycomb-COMPASS activity may have therapeutic efficacy in tumors that bear mutations in the genes encoding these epigenetic factors.
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Proteínas de Unión al ADN/metabolismo , Elementos de Facilitación Genéticos , Epigénesis Genética , Proteínas del Grupo Polycomb/metabolismo , Secuencia de Aminoácidos , Animales , Línea Celular Tumoral , Cromatina/metabolismo , Proteínas de Unión al ADN/química , Proteínas de Unión al ADN/genética , Regulación Neoplásica de la Expresión Génica , Histona Demetilasas/metabolismo , Ratones Desnudos , Mutación/genética , Proteínas Nucleares/metabolismo , Dedos de Zinc PHD , Unión Proteica , Análisis de Supervivencia , Proteínas Supresoras de Tumor/metabolismo , Ubiquitina Tiolesterasa/metabolismoRESUMEN
BACKGROUND: Emergency room physicians, trauma teams, and neurosurgeons are seeing increasing numbers of head-injured patients on anticoagulants, many of whom are nonoperative. Head injury and anticoagulation can lead to devastating consequences. These patients need immediate evaluation and often reversal of anticoagulation in order to decrease their high rates of morbidity and mortality. OBJECTIVE: To review data on the prevalence, risks, treatment, and complications of head-injured anticoagulated patients and provide a proposal for their anticoagulant management, and imaging requirements. METHODS: A PubMed database search was performed for articles on the prevalence, risks, treatment, and complications of patients who have sustained a head injury while on anticoagulant or antiplatelet agents. RESULTS: A total of 1877 articles were found, of which 64 were selected for use based on direct relevance, information quality, and contribution of the article to the current understanding of anticoagulated head injury patients. CONCLUSION: There are very few guidelines for the management of nonoperative head-injured patients. Rapid reversal guided by international normalized ratio values, Platelet Function Assays, computed tomography imaging of the head, and physical exam is suggested. The proposal presented in this paper enables patient management to begin quickly in a systematic approach, with the goal of achieving a significant decrease in the morbidity and mortality for the anticoagulated head-injured patient. Rapid reversal can potentially decrease mortality by as much as 38%.
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Anticoagulantes/uso terapéutico , Lesiones Traumáticas del Encéfalo/complicaciones , Lesiones Traumáticas del Encéfalo/terapia , Trastornos de la Coagulación Sanguínea/tratamiento farmacológico , Femenino , Humanos , Persona de Mediana Edad , Tomografía Computarizada por Rayos XRESUMEN
Rhabdoid tumors (RT) are highly aggressive and vastly unresponsive embryonal tumors. They are the most common malignant CNS tumors in infants below 6 months of age. Medulloblastomas (MB) are embryonal tumors that arise in the cerebellum and are the most frequent pediatric malignant brain tumors. Despite the advances in recent years, especially for the most favorable molecular subtypes of MB, the prognosis of patients with embryonal tumors remains modest with treatment related toxicity dreadfully high. Therefore, new targeted therapies are needed. The polo-like kinase 4 (PLK4) is a critical regulator of centriole duplication and consequently, mitotic progression. We previously established that PLK4 is overexpressed in RT and MB. We also demonstrated that inhibiting PLK4 with a small molecule inhibitor resulted in impairment of proliferation, survival, migration and invasion of RT cells. Here, we showed in MB the same effects that we previously described for RT. We also demonstrated that PLK4 inhibition induced apoptosis, senescence and polyploidy in RT and MB cells, thereby increasing the susceptibility of cancer cells to DNA-damaging agents. In order to test the hypothesis that PLK4 is a CNS druggable target, we demonstrated efficacy with oral administration to an orthotropic xenograft model. Based on these results, we postulate that targeting PLK4 with small-molecule inhibitors could be a novel strategy for the treatment of RT and MB and that PLK4 inhibitors (PLK4i) might be promising agents to be used solo or in combination with cytotoxic agents.
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BACKGROUND: The etiology of cerebral cavernous malformation hemorrhage is not well understood. Causative physiologic parameters preceding hemorrhagic cavernous malformation events are often not reported. We present a case of an individual with sequential simultaneous hemorrhages in multiple cerebral cavernous malformations with a new onset diagnosis of hypertension. CASE PRESENTATION: A 42-year-old white man was admitted to our facility with worsening headache, left facial and tongue numbness, dizziness, diplopia, and elevated blood pressure. His past medical history was significant for new onset diagnosis of hypertension and chronic seasonal allergies. Serial imaging over the ensuing 8 days revealed sequential hemorrhagic lesions. He underwent suboccipital craniotomy for resection of the lesions located in the fourth ventricle and right cerebellum. One month after surgery, he had near complete resolution of his symptoms with mild residual vertigo but symptomatic chronic hypertension. CONCLUSIONS: Many studies have focused on genetic and inflammatory mechanisms contributing to cerebral cavernous malformation rupture, but few have reported on the potential of hemodynamic changes contributing to cerebral cavernous malformation rupture. Systemic blood pressure changes clearly have an effect on angioma pressures. When considering the histopathological features of cerebral cavernous malformation architecture, changes in arterial pressure could cause meaningful alterations in hemorrhage propensity and patterns.