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1.
Mol Cancer ; 23(1): 121, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38853277

RESUMEN

BACKGROUND: Platinum resistance is the primary cause of poor survival in ovarian cancer (OC) patients. Targeted therapies and biomarkers of chemoresistance are critical for the treatment of OC patients. Our previous studies identified cell surface CD55, a member of the complement regulatory proteins, drives chemoresistance and maintenance of cancer stem cells (CSCs). CSCs are implicated in tumor recurrence and metastasis in multiple cancers. METHODS: Protein localization assays including immunofluorescence and subcellular fractionation were used to identify CD55 at the cell surface and nucleus of cancer cells. Protein half-life determinations were used to compare cell surface and nuclear CD55 stability. CD55 deletion mutants were generated and introduced into cancer cells to identify the nuclear trafficking code, cisplatin sensitivity, and stem cell frequency that were assayed using in vitro and in vivo models. Detection of CD55 binding proteins was analyzed by immunoprecipitation followed by mass spectrometry. Target pathways activated by CD55 were identified by RNA sequencing. RESULTS: CD55 localizes to the nucleus of a subset of OC specimens, ascites from chemoresistant patients, and enriched in chemoresistant OC cells. We determined that nuclear CD55 is glycosylated and derived from the cell surface pool of CD55. Nuclear localization is driven by a trafficking code containing the serine/threonine (S/T) domain of CD55. Nuclear CD55 is necessary for cisplatin resistance, stemness, and cell proliferation in OC cells. CD55 S/T domain is necessary for nuclear entry and inducing chemoresistance to cisplatin in both in vitro and in vivo models. Deletion of the CD55 S/T domain is sufficient to sensitize chemoresistant OC cells to cisplatin. In the nucleus, CD55 binds and attenuates the epigenetic regulator and tumor suppressor ZMYND8 with a parallel increase in H3K27 trimethylation and members of the Polycomb Repressive Complex 2. CONCLUSIONS: For the first time, we show CD55 localizes to the nucleus in OC and promotes CSC and chemoresistance. Our studies identify a therapeutic mechanism for treating platinum resistant ovarian cancer by blocking CD55 nuclear entry.


Asunto(s)
Antígenos CD55 , Núcleo Celular , Cromatina , Cisplatino , Resistencia a Antineoplásicos , Histonas , Células Madre Neoplásicas , Neoplasias Ováricas , Humanos , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/metabolismo , Neoplasias Ováricas/patología , Neoplasias Ováricas/genética , Femenino , Cisplatino/farmacología , Resistencia a Antineoplásicos/genética , Células Madre Neoplásicas/metabolismo , Células Madre Neoplásicas/patología , Células Madre Neoplásicas/efectos de los fármacos , Animales , Ratones , Antígenos CD55/metabolismo , Antígenos CD55/genética , Línea Celular Tumoral , Histonas/metabolismo , Núcleo Celular/metabolismo , Cromatina/metabolismo , Metilación , Ensayos Antitumor por Modelo de Xenoinjerto , Antineoplásicos/farmacología , Transporte de Proteínas
2.
J Neurooncol ; 163(3): 647-655, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37341842

RESUMEN

PURPOSE: Distinguishing radiation necrosis from tumor progression among patients with brain metastases previously treated with stereotactic radiosurgery represents a common diagnostic challenge. We performed a prospective pilot study to determine whether PET/CT with 18F-fluciclovine, a widely available amino acid PET radiotracer, repurposed intracranially, can accurately diagnose equivocal lesions. METHODS: Adults with brain metastases previously treated with radiosurgery presenting with a follow-up tumor-protocol MRI brain equivocal for radiation necrosis versus tumor progression underwent an 18F-fluciclovine PET/CT of the brain within 30 days. The reference standard for final diagnosis consisted of clinical follow-up until multidisciplinary consensus or tissue confirmation. RESULTS: Of 16 patients imaged from 7/2019 to 11/2020, 15 subjects were evaluable with 20 lesions (radiation necrosis, n = 16; tumor progression, n = 4). Higher SUVmax statistically significantly predicted tumor progression (AUC = 0.875; p = 0.011). Lesion SUVmean (AUC = 0.875; p = 0.018), SUVpeak (AUC = 0.813; p = 0.007), and SUVpeak-to-normal-brain (AUC = 0.859; p = 0.002) also predicted tumor progression, whereas SUVmax-to-normal-brain (p = 0.1) and SUVmean-to-normal-brain (p = 0.5) did not. Qualitative visual scores were significant predictors for readers 1 (AUC = 0.750; p < 0.001) and 3 (AUC = 0.781; p = 0.045), but not for reader 2 (p = 0.3). Visual interpretations were significant predictors for reader 1 (AUC = 0.898; p = 0.012) but not for reader 2 (p = 0.3) or 3 (p = 0.2). CONCLUSIONS: In this prospective pilot study of patients with brain metastases previously treated with radiosurgery presenting with a contemporary MRI brain with a lesion equivocal for radiation necrosis versus tumor progression, 18F-fluciclovine PET/CT repurposed intracranially demonstrated encouraging diagnostic accuracy, supporting the pursuit of larger clinical trials which will be necessary to establish diagnostic criteria and performance.


Asunto(s)
Neoplasias Encefálicas , Radiocirugia , Adulto , Humanos , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Radiocirugia/efectos adversos , Proyectos Piloto , Estudios Prospectivos , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/etiología , Necrosis/diagnóstico por imagen , Necrosis/etiología
3.
J Biol Chem ; 297(2): 100965, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34270956

RESUMEN

Signaling of semaphorin ligands via their plexin-neuropilin receptors is involved in tissue patterning in the developing embryo. These proteins play roles in cell migration and adhesion but are also important in disease etiology, including in cancer angiogenesis and metastasis. While some structures of the soluble domains of these receptors have been determined, the conformations of the full-length receptor complexes are just beginning to be elucidated, especially within the context of the plasma membrane. Pulsed-interleaved excitation fluorescence cross-correlation spectroscopy allows direct insight into the formation of protein-protein interactions in the membranes of live cells. Here, we investigated the homodimerization of neuropilin-1 (Nrp1), plexin A2, plexin A4, and plexin D1 using pulsed-interleaved excitation fluorescence cross-correlation spectroscopy. Consistent with previous studies, we found that Nrp1, plexin A2, and plexin A4 are present as dimers in the absence of exogenous ligand. Plexin D1, on the other hand, was monomeric under similar conditions, which had not been previously reported. We also found that plexin A2 and A4 assemble into a heteromeric complex. Stimulation with semaphorin 3A or semaphorin 3C neither disrupts nor enhances the dimerization of the receptors when expressed alone, suggesting that activation involves a conformational change rather than a shift in the monomer-dimer equilibrium. However, upon stimulation with semaphorin 3C, plexin D1 and Nrp1 form a heteromeric complex. This analysis of interactions provides a complementary approach to the existing structural and biochemical data that will aid in the development of new therapeutic strategies to target these receptors in cancer.


Asunto(s)
Moléculas de Adhesión Celular , Proteínas del Tejido Nervioso , Semaforinas , Membrana Celular/metabolismo , Movimiento Celular , Humanos , Transducción de Señal
4.
J Neurooncol ; 158(3): 341-348, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35486307

RESUMEN

PURPOSE: We sought to evaluate the effects of concurrent temozolomide-based chemoradiation therapy on neurocognitive function in patients with low-grade glioma (LGG). MATERIALS/METHODS: We included adult patients with LGG who were treated postoperatively with radiotherapy (RT) with concurrent and adjuvant temozolomide (TMZ). Patients were evaluated with comprehensive psychometric tests at baseline (prior to RT + TMZ) and at various time intervals following RT + TMZ. Baseline cognitive performance was analyzed by sex, age, education history, history of seizures, IDH mutation status, and 1p/19q codeletion status. Changes in neurocognitive performance were evaluated over time. RESULTS: Thirty-seven LGG patients (mean age 43.6, 59.5% male) had baseline neurocognitive evaluation. Patients with an age > 40 years old at diagnosis and those with an education > 16 years demonstrated superior baseline verbal memory as assessed by HVLT. No other cognitive domains showed differences when stratified by the variables mentioned above. A total of 22 LGG patients had baseline and post RT + TMZ neurocognitive evaluation. Overall, patients showed no statistical difference between group mean test scores prior to and following RT + TMZ on all psychometric measures (with the exception of HVLT Discrimination). CONCLUSION: Cognitive function remained stable following RT + TMZ in LGG patients evaluated prospectively up to 2 years. The anticipated analysis of RTOG 0424 will provide valuable neurocognitive outcomes specifically for high risk LGG patients treated with RT + TMZ.


Asunto(s)
Neoplasias Encefálicas , Glioma , Adulto , Antineoplásicos Alquilantes/uso terapéutico , Neoplasias Encefálicas/genética , Cognición , Femenino , Glioma/genética , Humanos , Masculino , Temozolomida/uso terapéutico
5.
J Neurooncol ; 156(3): 499-507, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35064450

RESUMEN

PURPOSE: Low-grade glioma (LGG) exhibits longer median survival than high-grade brain tumors, and thus impact of our therapies on patient quality of life remains a crucial consideration. This study evaluated the effects of concurrent temozolomide-based chemoradiation (RT + TMZ) or observation on quality of life (QOL) in patients with low-grade glioma. METHODS: We completed a retrospective cross-sectional study of adults with LGG who underwent surgery with known molecular classification from 1980 to 2018. Postoperatively, patients were either observed or received adjuvant concurrent temozolomide-based chemoradiation. EQ-5D and PHQ-9 depression screen were completed before outpatient visits every 2-3 months. Baseline score was defined as ± 30 days within initial operation. RESULTS: Of the 63 patients (mean age 44 ± 17 years, 51% female) with baseline EQ-5D or PHQ-9 depression screen data and at least one follow-up measure, 30 (48%) were observed and 33 (52%) received RT + TMZ. No significant decline was seen in EQ-5D or PHQ-9 scores at 3, 6, 9, 12, and 24 months compared to baseline scores for all patients. At each time point, there was no significant difference between those who were observed or received adjuvant therapy. The linear mixed model estimating PHQ-9 value or EQ-5D index demonstrated that there was no significant difference in PHQ-9 or EQ-5D index between treatment groups (p = 0.42 and p = 0.54, respectively) or time points (p = 0.24 and p = 0.99, respectively). CONCLUSION: Our study found no significant decline in patient QOL or depression scores as assessed by patient- reported outcome measures for patients with low-grade glioma up to 2 years following surgery. We found no difference between RT + TMZ compared to observation during this time frame. Additional follow-up can help identify the longer-term impact of treatment strategy on patient experience.


Asunto(s)
Neoplasias Encefálicas , Quimioradioterapia , Glioma , Calidad de Vida , Temozolomida , Espera Vigilante , Adulto , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/terapia , Estudios Transversales , Femenino , Glioma/patología , Glioma/terapia , Humanos , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Estudios Retrospectivos , Temozolomida/uso terapéutico , Resultado del Tratamiento
6.
Genes Dev ; 27(6): 670-82, 2013 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-23512660

RESUMEN

Epithelial-mesenchymal transition (EMT) is thought to be an important, possibly essential, component of the process of tumor dissemination and metastasis. About 20%-30% of Hras mutant mouse skin carcinomas induced by chemical initiation/promotion protocols have undergone EMT. Reduced exposure to TPA-induced chronic inflammation causes a dramatic reduction in classical papillomas and squamous cell carcinomas (SCCs), but the mice still develop highly invasive carcinomas with EMT properties, reduced levels of Hras and Egfr signaling, and frequent Ink4/Arf deletions. Deletion of Hras from the mouse germline also leads to a strong reduction in squamous tumor development, but tumors now acquire activating Kras mutations and exhibit more aggressive metastatic properties. We propose that invasive carcinomas can arise by different genetic and biological routes dependent on exposure to chronic inflammation and possibly from different target cell populations within the skin. Our data have implications for the use of inhibitors of inflammation or of Ras/Egfr pathway signaling for prevention or treatment of invasive cancers.


Asunto(s)
Carcinoma de Células Escamosas/patología , Inflamación/patología , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , Transducción de Señal , Neoplasias Cutáneas/patología , Animales , Carcinoma de Células Escamosas/genética , Proteínas Inhibidoras de las Quinasas Dependientes de la Ciclina/genética , Transición Epitelial-Mesenquimal , Receptores ErbB/metabolismo , Dosificación de Gen , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Marcadores Genéticos/genética , Ratones , Mutación , Proteínas Proto-Oncogénicas p21(ras)/genética , Neoplasias Cutáneas/genética
7.
Int J Hyperthermia ; 36(1): 986-992, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31544546

RESUMEN

Background: Treatment for locally recurrent breast cancer poses a significant challenge because the benefits in local control must be weighed against the increased risk of side effects of the treatment. Frequently, patients have been heavily pre-treated with radiation and several types of chemotherapy. Moreover, they often present with large volumes of bulky disease, further complicating management. Hyperthermia can be used to improve the efficacy of radiation, particularly in the setting of recurrent disease. Methods: We reviewed our clinical and dosimetric experience of breast cancer patients who received hyperthermia and radiation for recurrent breast cancer from 2011 to 2017. Thirty-six patients were treated with hyperthermia and radiation. Median follow-up was 11 months. Thirty patients (83.3%) received prior radiotherapy. The most commonly used radiation fraction scheme was 32 Gy in 8 fractions. The median radiation dose at the time of recurrence was 35.5 Gy (range 20-64 Gy). Mild temperature hyperthermia was delivered two times per week. Results: The median repeat radiation volume was 574 cc (range 11-3620 cc). Electrons, conventional photons, and IMRT radiation techniques were used. IMRT was used for large and complex treatment volumes and showed acceptable doses to organs at risk. The overall response rate was 61.1%. Complete response was observed in 17 patients (47.2%), partial response in 5 patients (13.9%), stable disease in 11 patients (30.6%), and progressive disease in 3 patients (8.3%). Twenty-six patients experienced acute grade 1 and 2 toxicities, primarily pain and erythema; and 26 experienced long-term grade 1 and 2 toxicities, mainly hyperpigmentation and lymphedema. Three patients developed new ulcerations that healed with conservative management. One patient developed pulmonary fibrosis resulting in mild dyspnea on exertion. Conclusion: Hyperthermia and radiation provide good local control with a favorable side effect profile. Thermoradiotherapy may be offered to patients with recurrent breast cancer, including those with extensive volumes of disease.


Asunto(s)
Neoplasias de la Mama/radioterapia , Hipertermia Inducida/métodos , Radiometría/métodos , Neoplasias de la Mama/patología , Femenino , Humanos , Recurrencia Local de Neoplasia , Dosificación Radioterapéutica
8.
Mol Carcinog ; 55(9): 1387-96, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-26310697

RESUMEN

The tumor suppressor TP53 can initiate a plethora of anti-proliferative effects to maintain genomic integrity under conditions of genotoxic stress. The N-terminal proline-rich domain (PRD) of TP53 is important in the regulation of TP53 activity and stability. A common polymorphism at codon 72 in this region has been associated with altered cancer risk in humans. The Trp53ΔP mouse, which carries a germline homozygous deletion of a region of the PRD, does not develop spontaneous tumors in a mixed 129/Sv and C57BL/6 genetic background, but is highly susceptible to a broad range of tumor types following total body exposure to 4 Gy gamma (γ) radiation. This contrasts with the tumor spectrum in Trp53 null (-/-) mice, which mainly develop thymic lymphomas and osteosarcomas. Analysis of genomic instability in tissues and cells from Trp53ΔP mice demonstrated elevated basal levels of aneuploidy, but this is not sufficient to drive spontaneous tumorigenesis, which requires an additional DNA damage stimulus. Levels of genomic instability did not increase significantly in Trp53ΔP mice following irradiation exposure, suggesting that other radiation effects including tissue inflammation, altered metabolism or autophagy, may play an important role. The Trp53ΔP mouse is a novel model to dissect the mechanisms of tumor development induced by radiation exposure. © 2015 Wiley Periodicals, Inc.


Asunto(s)
Carcinogénesis/genética , Inestabilidad Genómica , Neoplasias Inducidas por Radiación/genética , Proteína p53 Supresora de Tumor/genética , Secuencia de Aminoácidos , Animales , Autofagia , Femenino , Rayos gamma , Masculino , Ratones , Ratones Endogámicos C57BL , Poliploidía , Prolina/química , Prolina/genética , Eliminación de Secuencia , Proteína p53 Supresora de Tumor/química
9.
Stem Cells ; 32(8): 2033-47, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24831540

RESUMEN

Glioblastomas are highly lethal brain tumors containing tumor-propagating glioma stem cells (GSCs). The molecular mechanisms underlying the maintenance of the GSC phenotype are not fully defined. Here we demonstrate that the zinc finger and X-linked transcription factor (ZFX) maintains GSC self-renewal and tumorigenic potential by upregulating c-Myc expression. ZFX is differentially expressed in GSCs relative to non-stem glioma cells and neural progenitor cells. Disrupting ZFX by shRNA reduced c-Myc expression and potently inhibited GSC self-renewal and tumor growth. Ectopic expression of c-Myc to its endogenous level rescued the effects caused by ZFX disruption, supporting that ZFX controls GSC properties through c-Myc. Furthermore, ZFX binds to a specific sequence (GGGCCCCG) on the human c-Myc promoter to upregulate c-Myc expression. These data demonstrate that ZFX functions as a critical upstream regulator of c-Myc and plays essential roles in the maintenance of the GSC phenotype. This study also supports that c-Myc is a dominant driver linking self-renewal to malignancy.


Asunto(s)
Glioblastoma/patología , Factores de Transcripción de Tipo Kruppel/metabolismo , Células Madre Neoplásicas/patología , Proliferación Celular/fisiología , Células Cultivadas , Inmunoprecipitación de Cromatina , Técnica del Anticuerpo Fluorescente , Glioblastoma/metabolismo , Humanos , Immunoblotting , Inmunohistoquímica , Etiquetado Corte-Fin in Situ , Células Madre Neoplásicas/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
10.
J Neurooncol ; 122(3): 421-9, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25670390

RESUMEN

Cranial radiation can impact the cerebral vasculature in many ways, with a wide range of clinical manifestations. The incidence of these late effects including cerebrovascular accidents (CVAs), lacunar lesions, vascular occlusive disease including moyamoya syndrome, vascular malformations, and hemorrhage is not well known. This article reviews the preclinical findings regarding the pathophysiology of late radiation-induced vascular damage, and discusses the clinical incidence and risk factors for each type of vasculopathy. The pathophysiology is complex and dependent on the targeted blood vessels, and upregulation of pro-inflammatory and hypoxia-related genes. The risk factors for adult CVAs are similar to those for patients not exposed to cranial radiotherapy. For children, risks for late vascular complications include young age at radiotherapy, radiotherapy dose, NF1, tumor location, chemotherapy, and endocrine abnormalities. The incidence of late vascular complications of radiotherapy may be impacted by improved technology, therapeutic interventions, and appropriate follow up.


Asunto(s)
Trastornos Cerebrovasculares/etiología , Traumatismos por Radiación/etiología , Radioterapia/efectos adversos , Adulto , Neoplasias Encefálicas/radioterapia , Trastornos Cerebrovasculares/epidemiología , Niño , Bases de Datos Factuales/estadística & datos numéricos , Humanos , Factores de Riesgo
12.
Adv Exp Med Biol ; 853: 85-110, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25895709

RESUMEN

Radiation therapy is the most effective adjuvant treatment modality for virtually all patients with high-grade glioma. Its ability to improve patient survival has been recognized for decades. Cancer stem cells provide new insights into how tumor biology is affected by radiation and the role that this cell population can play in disease recurrence. Glioma stem cells possess a variety of intracellular mechanisms to resist and even flourish in spite of radiation, and their proliferation and maintenance appear tied to supportive stimuli from the tumor microenvironment. This chapter reviews the basis for our current use of radiation to treat high-grade gliomas, and addresses this model in the context of therapeutically resistant stem cells. We discuss the available evidence highlighting current clinical efforts to improve radiosensitivity, and newer targets worthy of further development.


Asunto(s)
Neoplasias Encefálicas/radioterapia , Glioma/radioterapia , Células Madre Neoplásicas/efectos de la radiación , Animales , Neoplasias Encefálicas/patología , Glioma/patología , Humanos , Células Madre Neoplásicas/patología , Tolerancia a Radiación , Microambiente Tumoral/efectos de la radiación
13.
J Appl Clin Med Phys ; 16(4): 31­39, 2015 07 08.
Artículo en Inglés | MEDLINE | ID: mdl-26218994

RESUMEN

The purpose of this study was to compare the single-isocenter, four-field hybrid IMRT with the two-isocenter techniques to treat the whole breast and supraclavicular fields and to investigate the intrafraction motions in both techniques in the superior direction. Fifteen breast cancer patients who underwent lumpectomy and adjuvant radiation to the whole breast and supraclavicular (SCV) fossa at our institution were selected for this study. Two planning techniques were compared for the treatment of the breast and SCV lymph nodes. The patients were divided into three subgroups according to the whole breast volume. For the two-isocenter technique, conventional wedged or field-within-a-field tangents (FIF) were used to match with the same anterior field for the SCV region. For the single-isocenter technique, four-field hybrid IMRT was used for the tangent fields matched with a half blocked anterior field for the SCV region. To simulate the intrafraction uncertainties in the longitudinal direction for both techniques, the treatment isocenters were shifted by 1 mm and 2 mm in the superior direction. The average breast clinical tumor volume (CTV) receiving 100% (V(100%)) of the prescription dose (50 Gy) was 99.3% ± 0.5% and 96.4% ± 1.2% for the for two-isocenter and single-isocenter plans (р < 0.05), respectively. The breast CTV receiving 95% of the prescription dose (V(95%)) was close to 100% in both techniques. The average breast CTV receiving 105% (V(105%)) of the prescription dose was 32.4% ± 19.3% and 23.8% ± 13.3% (р = 0.08). The percentage volume of the breast CTV receiving 110% of the dose was 0.4% ± 1.2% in the two-isocentric technique vs. 0.1% ± 0.2% in the single-isocentric technique. The average uniformity index was 0.91 ± 0.02 vs. 0.91 ± 0.01 in both techniques (p = 0.04), but had no clinical impact. The percentage volume of the contralateral breast receiving a dose of 1 Gy was less than 2.3% in small breast patients and insignificant for medium and large breast sizes. The percentage of the total lung volume receiving > 20 Gy (V(20Gy)) and the heart receiving > 30 Gy (V(30Gy)) were 13.6% vs. 14.3% (р = 0.03) and 1.25% vs. 1.2% (р = 0.62), respectively. Shifting the treatment isocenter by 1 mm and 2 mm superiorly showed that the average maximum dose to 1 cc of the breast volume was 55.5 ± 1.8 Gy and 58.6 ± 4.3 Gy in the two-isocentric technique vs. 56.4 ± 2.1 Gy and 59.1 ± 5.1 Gy in the single-isocentric technique (р = 0.46, 0.87), respectively. The single-isocenter technique using four-field hybrid IMRT approach resulted in comparable plan quality as the two-isocentric technique. The single-isocenter technique is more sensitive to intra-fraction motion in the superior direction compared to the two-isocentric technique. The advantages of the single-isocenter include elimination of isocentric errors due to couch and collimator rotations and reduction in treatment time. This study supports consideration of a single-isocenter four-field hybrid IMRT technique for patients undergoing breast and supraclavicular nodal irradiation.


Asunto(s)
Neoplasias de la Mama/patología , Neoplasias de la Mama/radioterapia , Ganglios Linfáticos/patología , Planificación de la Radioterapia Asistida por Computador/métodos , Radioterapia de Intensidad Modulada/métodos , Femenino , Humanos , Ganglios Linfáticos/efectos de la radiación , Dosificación Radioterapéutica , Estudios Retrospectivos
14.
Pac Symp Biocomput ; 29: 521-533, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38160304

RESUMEN

Advances in molecular characterization have reshaped our understanding of low-grade glioma (LGG) subtypes, emphasizing the need for comprehensive classification beyond histology. Lever-aging this, we present a novel approach, network-based Subnetwork Enumeration, and Analysis (nSEA), to identify distinct LGG patient groups based on dysregulated molecular pathways. Using gene expression profiles from 516 patients and a protein-protein interaction network we generated 25 million sub-networks. Through our unsupervised bottom-up approach, we selected 92 subnetworks that categorized LGG patients into five groups. Notably, a new LGG patient group with a lack of mutations in EGFR, NF1, and PTEN emerged as a previously unidentified patient subgroup with unique clinical features and subnetwork states. Validation of the patient groups on an independent dataset demonstrated the robustness of our approach and revealed consistent survival traits across different patient populations. This study offers a comprehensive molecular classification of LGG, providing insights beyond traditional genetic markers. By integrating network analysis with patient clustering, we unveil a previously overlooked patient subgroup with potential implications for prognosis and treatment strategies. Our approach sheds light on the synergistic nature of driver genes and highlights the biological relevance of the identified subnetworks. With broad implications for glioma research, our findings pave the way for further investigations into the mechanistic underpinnings of LGG subtypes and their clinical relevance.Availability: Source code and supplementary data are available at https://github.com/bebeklab/nSEA.


Asunto(s)
Neoplasias Encefálicas , Glioma , Humanos , Pronóstico , Biología Computacional , Glioma/genética , Glioma/patología , Algoritmos , Mapas de Interacción de Proteínas , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología
15.
Neuro Oncol ; 26(8): 1388-1401, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-38456228

RESUMEN

BACKGROUND: Hypoxia is associated with poor prognosis in many cancers including glioblastoma (GBM). Glioma stem-like cells (GSCs) often reside in hypoxic regions and serve as reservoirs for disease progression. Long non-coding RNAs (lncRNAs) have been implicated in GBM. However, the lncRNAs that modulate GSC adaptations to hypoxia are poorly understood. Identification of these lncRNAs may provide new therapeutic strategies to target GSCs under hypoxia. METHODS: lncRNAs induced by hypoxia in GSCs were identified by RNA-seq. Lung cancer-associated transcript-1 (LUCAT1) expression was assessed by qPCR, RNA-seq, Northern blot, single molecule FISH in GSCs, and interrogated in IvyGAP, The Cancer Genome Atlas, and CGGA databases. LUCAT1 was depleted by shRNA, CRISPR/Cas9, and CRISPR/Cas13d. RNA-seq, Western blot, immunohistochemistry, co-IP, ChIP, ChIP-seq, RNA immunoprecipitation, and proximity ligation assay were performed to investigate mechanisms of action of LUCAT1. GSC viability, limiting dilution assay, and tumorigenic potential in orthotopic GBM xenograft models were performed to assess the functional consequences of depleting LUCAT1. RESULTS: A new isoform of Lucat1 is induced by Hypoxia inducible factor 1 alpha (HIF1α) and Nuclear factor erythroid 2-related factor 2 (NRF2) in GSCs under hypoxia. LUCAT1 is highly expressed in hypoxic regions in GBM. Mechanistically, LUCAT1 formed a complex with HIF1α and its co-activator CBP to regulate HIF1α target gene expression and GSC adaptation to hypoxia. Depletion of LUCAT1 impaired GSC self-renewal. Silencing LUCAT1 decreased tumor growth and prolonged mouse survival in GBM xenograft models. CONCLUSIONS: A HIF1α-LUCAT1 axis forms a positive feedback loop to amplify HIF1α signaling in GSCs under hypoxia. LUCAT1 promotes GSC self-renewal and GBM tumor growth. LUCAT1 is a potential therapeutic target in GBM.


Asunto(s)
Neoplasias Encefálicas , Regulación Neoplásica de la Expresión Génica , Glioblastoma , Subunidad alfa del Factor 1 Inducible por Hipoxia , ARN Largo no Codificante , Humanos , ARN Largo no Codificante/genética , Glioblastoma/metabolismo , Glioblastoma/patología , Glioblastoma/genética , Animales , Ratones , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/genética , Células Madre Neoplásicas/metabolismo , Células Madre Neoplásicas/patología , Progresión de la Enfermedad , Ensayos Antitumor por Modelo de Xenoinjerto , Proliferación Celular , Células Tumorales Cultivadas , Ratones Desnudos , Línea Celular Tumoral , Biomarcadores de Tumor/metabolismo , Biomarcadores de Tumor/genética , Pronóstico , Apoptosis
16.
Neuro Oncol ; 26(9): 1651-1659, 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-38656347

RESUMEN

BACKGROUND: Single-session stereotactic radiosurgery (SRS) or surgical resection alone for brain metastases larger than 2 cm results in unsatisfactory local control. We conducted a phase I trial for brain metastases(>2 cm) to determine the safety of preoperative SRS at escalating doses. METHODS: Radiosurgery dose was escalated at 3 Gy increments for 3 cohorts based on maximum tumor dimension starting at: 18 Gy for >2-3 cm, 15 Gy for >3-4 cm, and 12 Gy for >4-6 cm. Dose-limiting toxicity was defined as grade III or greater acute toxicity. RESULTS: A total of 35 patients/36 lesions were enrolled. For tumor size >2-3 cm, patients were enrolled up to the second dose level (21 Gy); for >3-4 cm and >4-6 cm cohorts the third dose level (21 and 18 Gy, respectively) was reached. There were 2 DLTs in the >3-4 cm arm at 21 Gy. The maximum tolerated dose of SRS for >2-3 cm was not reached; and was 18 Gy for both >3-4 cm arm and >4-6 cm arm. With a median follow-up of 64.0 months, the 6- and 12-month local control rates were 85.9% and 76.6%, respectively. One patient developed grade 3 radiation necrosis at 5 months. The 2-year rate of leptomeningeal disease (LMD) was 0%. CONCLUSIONS: Preoperative SRS with dose escalation followed by surgical resection for brain metastases greater than 2 cm in size demonstrates acceptable acute toxicity. The phase II portion of the trial will be conducted at the maximum tolerated SRS doses.


Asunto(s)
Neoplasias Encefálicas , Radiocirugia , Humanos , Radiocirugia/métodos , Radiocirugia/efectos adversos , Neoplasias Encefálicas/secundario , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/cirugía , Persona de Mediana Edad , Masculino , Femenino , Anciano , Adulto , Dosis Máxima Tolerada , Dosificación Radioterapéutica , Estudios de Seguimiento , Cuidados Preoperatorios , Anciano de 80 o más Años
17.
Front Oncol ; 13: 1110473, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37007113

RESUMEN

In the United States, an individual's access to resources, insurance status, and wealth are critical social determinants that affect both the risk and outcomes of many diseases. One disease for which the correlation with socioeconomic status (SES) is less well-characterized is glioblastoma (GBM), a devastating brain malignancy. The aim of this study was to review the current literature characterizing the relationship between area-level SES and both GBM incidence and prognosis in the United States. A query of multiple databases was performed to identify the existing data on SES and GBM incidence or prognosis. Papers were filtered by relevant terms and topics. A narrative review was then constructed to summarize the current body of knowledge on this topic. We obtained a total of three papers that analyze SES and GBM incidence, which all report a positive correlation between area-level SES and GBM incidence. In addition, we found 14 papers that focus on SES and GBM prognosis, either overall survival or GBM-specific survival. Those studies that analyze data from greater than 1,530 patients report a positive correlation between area-level SES and individual prognosis, while those with smaller study populations report no significant relationship. Our report underlines the strong association between SES and GBM incidence and highlights the need for large study populations to assess SES and GBM prognosis to ideally guide interventions that improve outcomes. Further studies are needed to determine underlying socio-economic stresses on GBM risk and outcomes to identify opportunities for intervention.

18.
Front Oncol ; 13: 1110440, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36910642

RESUMEN

Brain metastases are a significant source of morbidity and mortality in patients with non-small cell lung cancer. Historically, surgery and radiation therapy have been essential to maintaining disease control within the central nervous system due to poorly penetrant conventional chemotherapy. With the advent of targeted therapy against actionable driver mutations, there is potential to control limited and asymptomatic intracranial disease and delay local therapy until progression. In this review paper, intracranial response rates and clinical outcomes to biological and immune therapies are summarized from the literature and appraised to assist clinical decision making and identify areas for further research. Future clinical trials ought to prioritize patient-centered quality of life and neurocognitive measures as major outcomes and specifically stratify patients based on mutational marker status, disease burden, and symptom acuity.

19.
Nat Commun ; 14(1): 2262, 2023 04 20.
Artículo en Inglés | MEDLINE | ID: mdl-37080989

RESUMEN

The Wnt pathway is frequently dysregulated in many cancers, underscoring it as a therapeutic target. Wnt inhibitors have uniformly failed in clinical trials. Here, we report a mechanism of WNT pathway activation through the Semaphorin 3 C neurodevelopmental program in glioma stem-like cells. Sema3C directs ß-catenin nuclear accumulation in a Rac1-dependent process, leading to transactivation of Wnt target genes. Sema3C-driven Wnt signaling occurred despite suppression of Wnt ligand secretion, suggesting that Sema3C drives canonical Wnt signaling independent of Wnt ligand binding. In a mouse model of glioblastoma, combined depletion of Sema3C and ß-catenin partner TCF1 extended animal survival more than single target inhibition alone. In human glioblastoma, Sema3C expression and Wnt pathway activation were highly concordant. Since Sema3C is frequently overexpressed in glioblastoma, Sema3C signaling may be a significant mechanism of resistance to upstream Wnt pathway inhibitors. Dual targeting of Sema3C and Wnt pathways may achieve clinically significant Wnt pathway inhibition.


Asunto(s)
Glioblastoma , Semaforinas , Animales , Humanos , Ratones , beta Catenina/genética , beta Catenina/metabolismo , Línea Celular Tumoral , Glioblastoma/genética , Glioblastoma/metabolismo , Ligandos , Semaforinas/genética , Vía de Señalización Wnt/genética
20.
bioRxiv ; 2023 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-38014234

RESUMEN

The glioblastoma microenvironment is enriched in immunosuppressive factors that potently interfere with the function of cytotoxic T lymphocytes. Cancer cells can directly impact the immune system, but the mechanisms driving these interactions are not completely clear. Here we demonstrate that the polyamine metabolite spermidine is elevated in the glioblastoma tumor microenvironment. Exogenous administration of spermidine drives tumor aggressiveness in an immune-dependent manner in pre-clinical mouse models via reduction of CD8+ T cell frequency and phenotype. Knockdown of ornithine decarboxylase, the rate-limiting enzyme in spermidine synthesis, did not impact cancer cell growth in vitro but did result in extended survival. Furthermore, glioblastoma patients with a more favorable outcome had a significant reduction in spermidine compared to patients with a poor prognosis. Our results demonstrate that spermidine functions as a cancer cell-derived metabolite that drives tumor progression by reducing CD8+T cell number and function.

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