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1.
Cancer ; 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38853532

RESUMO

BACKGROUND: Despite randomized trials demonstrating a mortality benefit to low-dose computed tomography screening to detect lung cancer, uptake of lung cancer screening (LCS) has been slow, and the benefits of screening remain unclear in clinical practice. METHODS: This study aimed to assess the impact of screening among patients in the Veterans Health Administration (VA) health care system diagnosed with lung cancer between 2011 and 2018. Lung cancer stage at diagnosis, lung cancer-specific survival, and overall survival between patients with cancer who did and did not receive screening before diagnosis were evaluated. We used Cox regression modeling and inverse propensity weighting analyses with lead time bias adjustment to correlate LCS exposure with patient outcomes. RESULTS: Of 57,919 individuals diagnosed with lung cancer in the VA system between 2011 and 2018, 2167 (3.9%) underwent screening before diagnosis. Patients with screening had higher rates of stage I diagnoses (52% vs. 27%; p ≤ .0001) compared to those who had no screening. Screened patients had improved 5-year overall survival rates (50.2% vs. 27.9%) and 5-year lung cancer-specific survival (59.0% vs. 29.7%) compared to unscreened patients. Among screening-eligible patients who underwent National Comprehensive Cancer Network guideline-concordant treatment, screening resulted in substantial reductions in all-cause mortality (adjusted hazard ratio [aHR], 0.79; 95% confidence interval [CI], 0.67-0.92; p = .003) and lung-specific mortality (aHR, 0.61; 95% CI, 0.50-0.74; p < .001). CONCLUSIONS: While LCS uptake remains limited, screening was associated with earlier stage diagnoses and improved survival. This large national study corroborates the value of LCS in clinical practice; efforts to widely adopt this vital intervention are needed.

2.
Hum Mol Genet ; 30(17): 1607-1617, 2021 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-34075397

RESUMO

Neurofibromatosis Type II (NF2) is an autosomal dominant cancer predisposition syndrome in which germline haploinsufficiency at the NF2 gene confers a greatly increased propensity for tumor development arising from tissues of neural crest derived origin. NF2 encodes the tumor suppressor, Merlin, and its biochemical function is incompletely understood. One well-established function of Merlin is as a negative regulator of group A serine/threonine p21-activated kinases (PAKs). In these studies we explore the role of PAK1 and its closely related paralog, PAK2, both pharmacologically and genetically, in Merlin-deficient Schwann cells and in a genetically engineered mouse model (GEMM) that develops spontaneous vestibular and spinal schwannomas. We demonstrate that PAK1 and PAK2 are both hyper activated in Merlin-deficient murine schwannomas. In preclinical trials, a pan Group A PAK inhibitor, FRAX-1036, transiently reduced PAK1 and PAK2 phosphorylation in vitro, but had insignificant efficacy in vivo. NVS-PAK1-1, a PAK1 selective inhibitor, had a greater but still minimal effect on our GEMM phenotype. However, genetic ablation of Pak1 but not Pak2 reduced tumor formation in our NF2 GEMM. Moreover, germline genetic deletion of Pak1 was well tolerated, while conditional deletion of Pak2 in Schwann cells resulted in significant morbidity and mortality. These data support the further development of PAK1-specific small molecule inhibitors and the therapeutic targeting of PAK1 in vestibular schwannomas and argue against PAK1 and PAK2 existing as functionally redundant protein isoforms in Schwann cells.


Assuntos
Neurofibromatose 2/genética , Quinases Ativadas por p21/metabolismo , Animais , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Genes Supressores de Tumor/efeitos dos fármacos , Indóis , Longevidade , Camundongos , Neurilemoma/genética , Neurofibromatose 2/metabolismo , Neurofibromina 2/genética , Fosforilação , Piperidinas , Pirimidinas , Células de Schwann/metabolismo , Quinases Ativadas por p21/genética
3.
Int J Gynecol Cancer ; 32(3): 297-303, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35256415

RESUMO

This review article highlights the treatment paradigms for early-stage endometrial cancer with a focus on the role of external beam radiation therapy. We aim for this review to serve as an introductory resource for gynecological oncologists, radiation oncologists, medical oncologists, and other practitioners to understand the treatments for this disease. The main treatment of endometrial cancer is surgical resection with total hysterectomy and bilateral salpingo-oophorectomy. The benefit of adjuvant radiation after surgery is primarily to prevent local recurrence. Patients with low risk of recurrence can be observed post-operatively. Vaginal cuff brachytherapy, which has been shown to be equally effective as pelvic radiation with fewer side effects, is typically recommended for high-intermediate risk patients (with characteristics such as lymphovascular space invasion, high grade, or significant myometrial invasion). In the adjuvant setting, pelvic radiation therapy is reserved for patients who have deeply invasive stage I grade 2 or 3 disease, stage II disease, and non-endometrioid histologies. In patients who are not medically operable, definitive treatment consists of brachytherapy±pelvic external beam radiation therapy. We have highlighted the main acute and long-term side effects of pelvic radiation as well as recommendations for symptom management and summarized promising evidence showing improved rates of toxicities with more conformal radiation techniques.


Assuntos
Braquiterapia , Neoplasias do Endométrio , Neoplasias Uterinas , Braquiterapia/métodos , Neoplasias do Endométrio/patologia , Feminino , Humanos , Histerectomia , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Radioterapia Adjuvante/métodos , Estudos Retrospectivos , Neoplasias Uterinas/radioterapia , Neoplasias Uterinas/cirurgia
4.
Hum Mol Genet ; 28(4): 572-583, 2019 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-30335132

RESUMO

Schwannomas are common, highly morbid and medically untreatable tumors that can arise in patients with germ line as well as somatic mutations in neurofibromatosis type 2 (NF2). These mutations most commonly result in the loss of function of the NF2-encoded protein, Merlin. Little is known about how Merlin functions endogenously as a tumor suppressor and how its loss leads to oncogenic transformation in Schwann cells (SCs). Here, we identify nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB)-inducing kinase (NIK) as a potential drug target driving NF-κB signaling and Merlin-deficient schwannoma genesis. Using a genomic approach to profile aberrant tumor signaling pathways, we describe multiple upregulated NF-κB signaling elements in human and murine schwannomas, leading us to identify a caspase-cleaved, proteasome-resistant NIK kinase domain fragment that amplifies pathogenic NF-κB signaling. Lentiviral-mediated transduction of this NIK fragment into normal SCs promotes proliferation, survival, and adhesion while inducing schwannoma formation in a novel in vivo orthotopic transplant model. Furthermore, we describe an NF-κB-potentiated hepatocyte growth factor (HGF) to MET proto-oncogene receptor tyrosine kinase (c-Met) autocrine feed-forward loop promoting SC proliferation. These innovative studies identify a novel signaling axis underlying schwannoma formation, revealing new and potentially druggable schwannoma vulnerabilities with future therapeutic potential.


Assuntos
Neurilemoma/genética , Neurofibromatose 2/genética , Neurofibromina 2/genética , Proteínas Serina-Treonina Quinases/genética , Animais , Comunicação Autócrina/genética , Carcinogênese/genética , Caspase 1/genética , Proliferação de Células/genética , Modelos Animais de Doenças , Regulação Neoplásica da Expressão Gênica , Fator de Crescimento de Hepatócito/genética , Humanos , Camundongos , Terapia de Alvo Molecular , NF-kappa B/genética , Neurilemoma/complicações , Neurilemoma/tratamento farmacológico , Neurilemoma/patologia , Neurofibromatose 2/complicações , Neurofibromatose 2/tratamento farmacológico , Neurofibromatose 2/patologia , Complexo de Endopeptidases do Proteassoma/genética , Proto-Oncogene Mas , Proteínas Proto-Oncogênicas c-met/genética , Células de Schwann , Transdução de Sinais/genética , Quinase Induzida por NF-kappaB
5.
Blood ; 131(20): 2247-2255, 2018 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-29615403

RESUMO

Mantle cell lymphoma (MCL) is characterized by increased B-cell receptor (BCR) signaling, and BTK inhibition is an effective therapeutic intervention in MCL patients. The mechanisms leading to increased BCR signaling in MCL are poorly understood, as mutations in upstream regulators of BCR signaling such as CD79A, commonly observed in other lymphomas, are rare in MCL. The transcription factor SOX11 is overexpressed in the majority (78% to 93%) of MCL patients and is considered an MCL-specific oncogene. So far, attempts to understand SOX11 function in vivo have been hampered by the lack of appropriate animal models, because germline deletion of SOX11 is embryonically lethal. We have developed a transgenic mouse model (Eµ-SOX11-EGFP) in the C57BL/6 background expressing murine SOX11 and EGFP under the control of a B-cell-specific IgH-Eµ enhancer. The overexpression of SOX11 exclusively in B cells exhibits oligoclonal B-cell hyperplasia in the spleen, bone marrow, and peripheral blood, with an immunophenotype (CD5+CD19+CD23-) identical to human MCL. Furthermore, phosphocytometric time-of-flight analysis of the splenocytes from these mice shows hyperactivation of pBTK and other molecules in the BCR signaling pathway, and serial bone marrow transplant from transgenic donors produces lethality with decreasing latency. We report here that overexpression of SOX11 in B cells promotes BCR signaling and a disease phenotype that mimics human MCL.


Assuntos
Linfoma de Célula do Manto/metabolismo , Linfoma de Célula do Manto/patologia , Receptores de Antígenos de Linfócitos B/metabolismo , Fatores de Transcrição SOXC/metabolismo , Transdução de Sinais , Microambiente Tumoral , Animais , Linfócitos B/metabolismo , Linfócitos B/patologia , Biomarcadores , Linhagem Celular Tumoral , Evolução Clonal , Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Cadeias Pesadas de Imunoglobulinas , Linfoma de Célula do Manto/genética , Camundongos , Camundongos Transgênicos , Fenótipo , Fatores de Transcrição SOXC/genética
6.
Int J Radiat Oncol Biol Phys ; 118(4): 963-970, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-37793573

RESUMO

PURPOSE: Adjuvant durvalumab after definitive chemoradiotherapy (CRT) for unresectable stage III non-small cell lung cancer (NSCLC) is well-tolerated in clinical trials. However, pneumonitis rates outside of clinical trials remain poorly defined with CRT followed by durvalumab. We aimed to describe the influence of durvalumab on pneumonitis rates among a large cohort of patients with stage III NSCLC. METHODS AND MATERIALS: We studied patients with stage III NSCLC in the national Veterans Health Administration from 2015 to 2021 who received concurrent CRT alone or with adjuvant durvalumab. We defined pneumonitis as worsening respiratory symptoms with radiographic changes within 2 years of CRT and graded events according to National Cancer Institute Common Terminology Criteria for Adverse Events version 4.03. We used Cox regression to analyze risk factors for pneumonitis and the effect of postbaseline pneumonitis on overall survival. RESULTS: Among 1994 patients (989 CRT alone, 1005 CRT followed by adjuvant durvalumab), the 2-year incidence of grade 2 or higher pneumonitis was 13.9% for CRT alone versus 22.1% for CRT plus durvalumab (unadjusted P < .001). On multivariable analysis, durvalumab was associated with higher risk of grade 2 pneumonitis (hazard ratio, 1.45; 95% CI, 1.09-1.93; P = .012) but not grade 3 to 5 pneumonitis (P = .2). Grade 3 pneumonitis conferred worse overall survival (hazard ratio, 2.51; 95% CI, 2.06-3.05; P < .001) but grade 2 pneumonitis did not (P = .4). CONCLUSIONS: Adjuvant durvalumab use was associated with increased risk of low-grade but not higher-grade pneumonitis. Reassuringly, low-grade pneumonitis did not increase mortality risk. We observed increased rates of high-grade pneumonitis relative to clinical trials; the reasons for this require further study.


Assuntos
Anticorpos Monoclonais , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Pneumonia , Humanos , Carcinoma Pulmonar de Células não Pequenas/terapia , Neoplasias Pulmonares/terapia , Adjuvantes Imunológicos , Pneumonia/induzido quimicamente , Pneumonia/epidemiologia , Quimiorradioterapia/efeitos adversos
7.
Head Neck ; 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38680087

RESUMO

BACKGROUND: Post-treatment surveillance recommendations for oropharyngeal cancer do not vary with p16 status despite the differences in outcomes. The optimal algorithm personalizing follow-up for these patients remains undefined. Here, we evaluate the feasibility and utility of incorporating electronic patient-reported outcomes (ePROs) and circulating tumor DNA (ctDNA) into routine surveillance for patients treated for p16+ oropharynx cancer. METHODS: A prospective registry was developed in which ePROs and ctDNA were incorporated into routine surveillance among patients with oropharynx cancer. ePROs were emailed monthly for 1 year and blood HPV ctDNA testing was performed every 3-6 months. The primary objective was to assess patient compliance with ePRO-based surveillance with adequate compliance defined as ≥85% of patients completing monthly ePROs. Sensitivity, specificity, and positive/negative predictive values to detect recurrence were calculated for ePROs, HPV ctDNA, or the combination. RESULTS: Of 122 patients who initially expressed interest, 76 completed the electronic consent process and 44/76 (58%) were compliant with monthly surveys over 1 year; thus adequate compliance was not achieved. Technical difficulties associated with ePRO receipt through email largely limited participation. Provider feedback was significantly associated with heightened ePRO compliance. One hundred and six patients had ctDNA testing with a mean number of three tests per patient. Sensitivity to detect recurrence was 75% for the combination of ePROs and ctDNA. CONCLUSION: Despite lower than anticipated compliance with ePROs, our findings show promise for incorporation of HPV ctDNA into surveillance paradigms for HPV-related oropharynx cancer with suggestions of methods to optimize ePRO formats for personalized surveillance.

8.
Artigo em Inglês | MEDLINE | ID: mdl-38971385

RESUMO

INTRODUCTION: Local failure rates after treatment for locally advanced non-small-cell lung cancer (NSCLC) remain high. Efforts to improve local control with uniform dose-escalation or dose-escalation to mid-treatment PET-avid residual disease have been limited by heightened toxicity. This trial aimed to refine response-based adaptive radiation (RT) and minimize toxicity by incorporating FDG-PET and V/Q SPECT imaging mid-treatment. METHODS: 47 patients with Stage IIA-III unresectable NSCLC were prospectively enrolled in this single-institution trial (NCT02492867). Patients received concurrent chemoradiation with personalized response-based adaptive RT over 30 fractions incorporating V/Q SPECT and FDG-PET. The first 21 fractions (46.2Gy at 2.2 Gy/fraction) were delivered to the tumor while minimizing dose to SPECT-defined functional lung. The plan was then adapted for the final 9 fractions (2.2-3.8Gy/fraction) up to a total of 80.4Gy, based on mid-treatment FDG-PET tumor response to escalate dose to residual tumor while minimizing dose to SPECT-defined functional lung. Non-progressing patients received consolidative carboplatin/paclitaxel or durvalumab. The primary endpoint of the study was ≥ grade 2 lung and esophageal toxicities. Secondary endpoints included time to local progression, tumor response, and overall survival. RESULTS: At one year post-treatment, the rates of grade 2 and grade 3 pneumonitis were 21.3% and 2.1%, respectively, with no difference in pneumonitis rates among patients who received and did not receive adjuvant durvalumab (p=0.74). While there were no grade 3 esophageal-related toxicities, 66.0% of patients experienced grade 2 esophagitis. 1- and 2-year local control rates were 94.5% (95% CI, 87.4% - 100%) and 87.5% (95% CI, 76.7% - 100%), respectively. Overall survival was 82.8% (95% CI, 72.6% -94.4%) at 1 year and 62.3% (95% CI, 49.6%-78.3%) at 2 years. CONCLUSIONS: Response-based adaptive dose-escalation accounting for tumor change and normal tissue function during treatment provided excellent local control, comparable toxicity to standard chemoradiation, and did not increase toxicity with adjuvant immunotherapy.

9.
J Elder Abuse Negl ; 25(5): 438-52, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23941424

RESUMO

This case study presents details of the life of one older man who lived in seclusion and squalor, surrounded by hoarded possessions. This man was one participant of a focused ethnography of eight older adults who received home care. All participants in the original ethnography were identified by their community care coordinators as exhibiting hoarding behaviors. The case study presented here provides rich narrative and photographic detail in order to add strength to what has already been presented in previous research articles about compulsive acquisition. The narratives reveal examples of debilitating dysfunction, distress associated with decision making, broad acquisition of free things, compulsive buying, and ritualistic discarding. Quotes included in the case study stem from the original ethnography.


Assuntos
Atividades Cotidianas/psicologia , Transtorno de Acumulação/psicologia , Controle Interno-Externo , Relações Interpessoais , Qualidade de Vida/psicologia , Idoso , Comportamento Compulsivo/psicologia , Zeladoria , Humanos , Masculino , Motivação , Narração , Autoimagem
10.
Health Aff (Millwood) ; 42(7): 946-955, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37406228

RESUMO

Immune checkpoint inhibitors, a class of drugs used in approximately forty unique cancer indications, are a sizable component of the economic burden of cancer care in the US. Instead of personalized weight-based dosing, immune checkpoint inhibitors are most commonly administered at "one-size-fits-all" flat doses that are higher than necessary for the vast majority of patients. We hypothesized that personalized weight-based dosing along with common stewardship efforts at the pharmacy level, such as dose rounding and vial sharing, would lead to reductions in immune checkpoint inhibitor use and lower spending. Using data from the Veterans Health Administration (VHA) and Medicare drug prices, we estimated reductions in immune checkpoint inhibitor use and spending that would be associated with pharmacy-level stewardship strategies, in a case-control simulation study of individual patient-level immune checkpoint inhibitor administration events. We identified baseline annual VHA spending for these drugs of approximately $537 million. Combining weight-based dosing, dose rounding, and pharmacy-level vial sharing would generate expected annual VHA health system savings of $74 million (13.7 percent). We conclude that adoption of pharmacologically justified immune checkpoint inhibitor stewardship measures would generate sizable reductions in spending for these drugs. Combining these operational innovations with value-based drug price negotiation enabled by recent policy changes may improve the long-term financial viability of cancer care in the US.


Assuntos
Neoplasias , Farmácias , Farmácia , Idoso , Humanos , Estados Unidos , Inibidores de Checkpoint Imunológico , Medicare , Estudos de Casos e Controles , Custos de Medicamentos , Neoplasias/tratamento farmacológico
11.
J Diabetes Sci Technol ; 17(2): 353-363, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-34719972

RESUMO

BACKGROUND: Patient education is a fundamental aspect of self-management of diabetes. The aim of this study was to understand whether a social media platform is a viable method to deliver education to people with diabetes and understand if people would engage and interact with it. METHODS: Education sessions were provided via 3 platforms in a variety of formats. "Tweetorials" and quizzes were delivered on the diabetes101 Twitter account, a virtual conference via Zoom and video presentations uploaded to YouTube. Audience engagement during and after the sessions were analyzed using social media metrics including impressions and engagement rate using Twitter analytics, Tweepsmap, and YouTube Studio. RESULTS: A total of 22 "tweetorial" sessions and 5 quizzes with a total of 151 polls (both in tweetorial and quiz sessions) receiving a total of 21,269 votes took place. Overall, the 1-h tweetorial sessions gained 1,821,088 impressions with an engagement rate of 6.3%. The sessions received a total of 2,341 retweets, 2,467 replies and 10,060 likes. The quiz days included 113 polls receiving 16,069 votes. The conference covered 8 topics and was attended live by over 100 people on the day. The video presentations on YouTube have received a total of 2,916 views with a watch time of 281 h and 8,847 impressions. CONCLUSION: Despite the limitations of social media, it can be harnessed to provide relevant reliable information and education about diabetes allowing people the time and space to learn at their own pace.


Assuntos
Diabetes Mellitus , Mídias Sociais , Humanos , Pandemias , Diabetes Mellitus/terapia
12.
Pract Radiat Oncol ; 13(2): 112-121, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36460181

RESUMO

PURPOSE: Cannabis use rates are increasing in the United States. Patients with cancer use cannabis for many reasons, even without high-quality supporting data. This study sought to characterize cannabis use among patients seen in radiation oncology in a state that has legalized adult nonmedical use cannabis and to identify key cannabis-related educational topics. METHODS AND MATERIALS: Cannabis history was documented by providers using a structured template at patient visits in an academic radiation oncology practice October 2020 to November 2021. Cannabis use data, including recency/frequency of use, reason, and mode of administration, were summarized, and logistic regression was used to explore associations between patient and disease characteristics and recent cannabis use. A multivariable model employed stepwise variable selection using the Akaike Information Criterion. RESULTS: Of 3143 patients total, 91 (2.9%) declined to answer cannabis use questions, and 343 (10.9%) endorsed recent use (≤1 month ago), 235 (7.5%) noted nonrecent use (>1 month ago), and 2474 (78.7%) denied history of cannabis use. In multivariable analyses, those ≥50 years old (odds ratio [OR], 0.409; 95% confidence interval [CI], 0.294-0.568; P < .001) or with history of prior courses of radiation (OR, 0.748; 95% CI, 0.572-0.979; P = .034) were less likely, and those with a mental health diagnosis not related to substance use (OR, 1.533; 95% CI, 1.171-2.005; P = .002) or who smoked tobacco (OR, 3.003; 95% CI, 2.098-4.299; P < .001) were more likely to endorse recent cannabis use. Patients reported pain, insomnia, and anxiety as the most common reasons for use. Smoking was the most common mode of administration. CONCLUSIONS: Patients are willing to discuss cannabis use with providers and reported recent cannabis use for a variety of reasons. Younger patients new to oncologic care and those with a history of mental illness or tobacco smoking may benefit most from discussions about cannabis given higher rates of cannabis use in these groups.


Assuntos
Cannabis , Fumar Maconha , Radioterapia (Especialidade) , Transtornos Relacionados ao Uso de Substâncias , Adulto , Humanos , Estados Unidos , Pessoa de Meia-Idade , Cannabis/efeitos adversos , Transtornos Relacionados ao Uso de Substâncias/complicações , Dor
13.
Antioxid Redox Signal ; 39(13-15): 942-956, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-36852494

RESUMO

Aims: Targeting tumor metabolism may improve the outcomes for patients with glioblastoma (GBM). To further preclinical efforts targeting metabolism in GBM, we tested the hypothesis that brain tumors can be stratified into distinct metabolic groups with different patient outcomes. Therefore, to determine if tumor metabolites relate to patient survival, we profiled the metabolomes of human gliomas and correlated metabolic information with clinical data. Results: We found that isocitrate dehydrogenase-wildtype (IDHwt) GBMs are metabolically distinguishable from IDH mutated (IDHmut) astrocytomas and oligodendrogliomas. Survival of patients with IDHmut gliomas was expectedly more favorable than those with IDHwt GBM, and metabolic signatures can stratify IDHwt GBMs subtypes with varying prognoses. Patients whose GBMs were enriched in amino acids had improved survival, while those whose tumors were enriched for nucleotides, redox molecules, and lipid metabolites fared more poorly. These findings were recapitulated in validation cohorts using both metabolomic and transcriptomic data. Innovation: Our results suggest the existence of metabolic subtypes of GBM with differing prognoses, and further support the concept that metabolism may drive the aggressiveness of human gliomas. Conclusions: Our data show that metabolic signatures of human gliomas can inform patient survival. These findings may be used clinically to tailor novel metabolically targeted agents for GBM patients with different metabolic phenotypes. Antioxid. Redox Signal. 39, 942-956.


Assuntos
Astrocitoma , Neoplasias Encefálicas , Glioblastoma , Glioma , Humanos , Mutação , Glioma/genética , Glioma/metabolismo , Astrocitoma/genética , Astrocitoma/metabolismo , Astrocitoma/patologia , Glioblastoma/genética , Glioblastoma/metabolismo , Glioblastoma/patologia , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Isocitrato Desidrogenase/genética , Isocitrato Desidrogenase/metabolismo
14.
medRxiv ; 2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37961582

RESUMO

The brain avidly consumes glucose to fuel neurophysiology. Cancers of the brain, such as glioblastoma (GBM), lose aspects of normal biology and gain the ability to proliferate and invade healthy tissue. How brain cancers rewire glucose utilization to fuel these processes is poorly understood. Here we perform infusions of 13 C-labeled glucose into patients and mice with brain cancer to define the metabolic fates of glucose-derived carbon in tumor and cortex. By combining these measurements with quantitative metabolic flux analysis, we find that human cortex funnels glucose-derived carbons towards physiologic processes including TCA cycle oxidation and neurotransmitter synthesis. In contrast, brain cancers downregulate these physiologic processes, scavenge alternative carbon sources from the environment, and instead use glucose-derived carbons to produce molecules needed for proliferation and invasion. Targeting this metabolic rewiring in mice through dietary modulation selectively alters GBM metabolism and slows tumor growth. Significance: This study is the first to directly measure biosynthetic flux in both glioma and cortical tissue in human brain cancer patients. Brain tumors rewire glucose carbon utilization away from oxidation and neurotransmitter production towards biosynthesis to fuel growth. Blocking these metabolic adaptations with dietary interventions slows brain cancer growth with minimal effects on cortical metabolism.

15.
Front Bioeng Biotechnol ; 10: 1003127, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36263356

RESUMO

Many countries have worked diligently to establish and implement policies and processes to regulate high consequence pathogens and toxins that could have a significant public health impact if misused. In the United States, the Antiterrorism and Effective Death Penalty Act of 1996 (Public Law 104-132, 1996), as amended by the Bioterrorism Preparedness and Response Act of 2002 (Public Law 107-188, 2002) requires that the Department of Health and Human Services (HHS) [through the Centers for Disease Control and Prevention (CDC)] establish a list of bacteria, viruses, and toxins that have the potential to pose a severe threat to public health and safety. Currently, this list is reviewed and updated on a biennial basis using input from subject matter experts (SMEs). We have developed decision support framework (DSF) approaches to facilitate selection of select toxins and, where toxicity data are known, conducted modelling studies to inform selection of toxin amounts that should be excluded from select agent regulations. Exclusion limits allow laboratories to possess toxins under an established limit to support their research or teaching activities without the requirement to register with the Federal Select Agent Program. Fact sheets capturing data from a previously vetted SME workshop convened by CDC, literature review and SME input were developed to assist in evaluating toxins using the DSF approach. The output of the DSF analysis agrees with the current select toxin designations, and no other toxins evaluated in this study were recommended for inclusion on the select agent and toxin list. To inform the selection of exclusion limits, attack scenarios were developed to estimate the amount of toxin needed to impact public health. Scenarios consisted of simulated aerosol releases of a toxin in high-population-density public facilities and the introduction of a toxin into a daily consumable product supply chain. Using published inhalation and ingestion median toxic dose (TD50) and median lethal dose (LD50) values, where available, a range of toxin amounts was examined to estimate the number of people exposed to these amounts in these scenarios. Based on data generated by these models, we proposed toxin exclusion values corresponding to levels below those that would trigger a significant public health response (i.e., amounts estimated to expose up to ten people by inhalation or one hundred people by ingestion to LD50 or TD50 levels of toxin in the modeled scenarios).

16.
Mol Oncol ; 16(4): 860-884, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34058059

RESUMO

The Fanconi anemia (FA) pathway safeguards genomic stability through cell cycle regulation and DNA damage repair. The canonical tumor suppressive role of FA proteins in the repair of DNA damage during interphase is well established, but their function in mitosis is incompletely understood. Here, we performed a kinome-wide synthetic lethality screen in FANCA-/- fibroblasts, which revealed multiple mitotic kinases as necessary for survival of FANCA-deficient cells. Among these kinases, we identified the depletion of the centrosome kinase SIK2 as synthetic lethal upon loss of FANCA. We found that FANCA colocalizes with SIK2 at multiple mitotic structures and regulates the activity of SIK2 at centrosomes. Furthermore, we found that loss of FANCA exacerbates cell cycle defects induced by pharmacological inhibition of SIK2, including impaired G2-M transition, delayed mitotic progression, and cytokinesis failure. In addition, we showed that inhibition of SIK2 abrogates nocodazole-induced prometaphase arrest, suggesting a novel role for SIK2 in the spindle assembly checkpoint. Together, these findings demonstrate that FANCA-deficient cells are dependent upon SIK2 for survival, supporting a preclinical rationale for targeting of SIK2 in FA-disrupted cancers.


Assuntos
Anemia de Fanconi , Ciclo Celular , Anemia de Fanconi/genética , Anemia de Fanconi/metabolismo , Anemia de Fanconi/patologia , Proteína do Grupo de Complementação A da Anemia de Fanconi/genética , Proteína do Grupo de Complementação A da Anemia de Fanconi/metabolismo , Proteínas de Grupos de Complementação da Anemia de Fanconi/genética , Humanos , Mitose/genética , Proteínas Serina-Treonina Quinases , Mutações Sintéticas Letais
17.
Analyst ; 136(5): 913-9, 2011 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-21127794

RESUMO

Constructing flow-through reactors for chemiluminescence detection by machining channels into polymer disks has enabled the exploration of new configurations and materials that can improve signal intensity beyond that attainable with the traditional coiled-tubing design. Several approaches to merge reactant solutions were examined: an intersection, chamber or deeper well in the centre of a serpentine configuration flow-cell (directly in front of a photomultiplier tube), or a confluence point outside the detection zone. For several analytically useful, rapid chemiluminescence reactions, the single-inlet flow-cell with external Y-piece was most suitable, but for others (such as KMnO(4)/Mn(II) with morphine, and [Ir(f-ppy)(2)BPS](-) with fluoroquinolones) the dual-inlet configuration provided greater signals. The introduction of central mixing zones with larger widths than the channel reduced the chemiluminescence response. The reversing turns of a serpentine channel promote efficient mixing and greater chemiluminescence intensities than a spiral channel, but increasing the sharpness of the turns created areas of poor solution flow and decreased the chemiluminescence response. Teflon disks impregnated with glass microspheres increased the chemiluminescence signals by 13%-17%, due to the greater reflection of stray light towards the photodetector.

18.
Clin Cancer Res ; 27(16): 4652-4663, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34158358

RESUMO

PURPOSE: Mantle cell lymphoma (MCL) is a fatal subtype of non-Hodgkin lymphoma. SOX11 transcription factor is overexpressed in the majority of nodal MCL. We have previously reported that B cell-specific overexpression of SOX11 promotes MCL pathogenesis via critically increasing BCR signaling in vivo. SOX11 is an attractive target for MCL therapy; however, no small-molecule inhibitor of SOX11 has been identified to date. Although transcription factors are generally considered undruggable, the ability of SOX11 to bind to the minor groove of DNA led us to hypothesize that there may exist cavities at the protein-DNA interface that are amenable to targeting by small molecules. EXPERIMENTAL DESIGN: Using a combination of in silico predictions and experimental validations, we report here the discovery of three structurally related compounds (SOX11i) that bind SOX11, perturb its interaction with DNA, and effect SOX11-specific anti-MCL cytotoxicity. RESULTS: We find mechanistic validation of on-target activity of these SOX11i in the inhibition of BCR signaling and the transcriptional modulation of SOX11 target genes, specifically, in SOX11-expressing MCL cells. One of the three SOX11i exhibits relatively superior in vitro activity and displays cytotoxic synergy with ibrutinib in SOX11-expressing MCL cells. Importantly, this SOX11i induces cytotoxicity specifically in SOX11-positive ibrutinib-resistant MCL patient samples and inhibits Bruton tyrosine kinase phosphorylation in a xenograft mouse model derived from one of these subjects. CONCLUSIONS: Taken together, our results provide a foundation for therapeutically targeting SOX11 in MCL by a novel class of small molecules.


Assuntos
Linfoma de Célula do Manto/tratamento farmacológico , Fatores de Transcrição SOXC/antagonistas & inibidores , Animais , Humanos , Camundongos , Células Tumorais Cultivadas
19.
Clin Lung Cancer ; 22(3): e342-e359, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-32736936

RESUMO

INTRODUCTION: The impact of lung parenchymal-only failure on patient survival after stereotactic ablative body radiotherapy (SABR) for early-stage non-small-cell lung cancer (NSCLC) remains unclear. PATIENTS AND METHODS: The study population included 481 patients with early-stage NSCLC who were treated with 3- to 5-fraction SABR between 2000 and 2016. The primary study objective was to assess the impact of out-of-field lung parenchymal-only failure (OLPF) on overall survival (OS). RESULTS: At a median follow-up of 5.9 years, the median OS was 2.7 years for all patients. Patients with OLPF did not have a significantly different OS compared to patients without failure (P = .0952, median OS 4.1 years with failure vs. 2.6 years never failure). Analysis in a 1:1 propensity score-matched cohort for Karnofsky performance status, comorbidity score, and smoking status showed no differences in OS between patients without failure and those with OLPF (P = .8). In subgroup analyses exploring the impact of time of failure on OS, patients with OLPF 6 months or more after diagnosis did not have significantly different OS compared to those without failure, when accounting for immortal time bias (P = .3, median OS 4.3 years vs. 3.5 years never failure). Only 7 patients in our data set experienced failure within 6 months of treatment, of which only 4 were confirmed to be true failures; therefore, limited data are available in our cohort on the impact of OLPF for ≤ 6 months on OS. CONCLUSION: OLPF after SABR for early-stage NSCLC does not appear to adversely affect OS, especially if occurring at least 6 months after SABR. More studies are needed to understand if OLPF within 6 months of SABR is associated with adverse OS. These data are useful when discussing prognosis of lung parenchymal failures after initial SABR.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/radioterapia , Neoplasias Pulmonares/radioterapia , Tecido Parenquimatoso/patologia , Radiocirurgia/métodos , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/patologia , Estudos de Coortes , Feminino , Seguimentos , Humanos , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Taxa de Sobrevida , Resultado do Tratamento
20.
Front Oncol ; 11: 752933, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34804941

RESUMO

Fanconi anemia (FA) is a disease of genomic instability and cancer. In addition to DNA damage repair, FA pathway proteins are now known to be critical for maintaining faithful chromosome segregation during mitosis. While impaired DNA damage repair has been studied extensively in FA-associated carcinogenesis in vivo, the oncogenic contribution of mitotic abnormalities secondary to FA pathway deficiency remains incompletely understood. To examine the role of mitotic dysregulation in FA pathway deficient malignancies, we genetically exacerbated the baseline mitotic defect in Fancc-/- mice by introducing heterozygosity of the key spindle assembly checkpoint regulator Mad2. Fancc-/-;Mad2+/- mice were viable, but died from acute myeloid leukemia (AML), thus recapitulating the high risk of myeloid malignancies in FA patients better than Fancc-/-mice. We utilized hematopoietic stem cell transplantation to propagate Fancc-/-; Mad2+/- AML in irradiated healthy mice to model FANCC-deficient AMLs arising in the non-FA population. Compared to cells from Fancc-/- mice, those from Fancc-/-;Mad2+/- mice demonstrated an increase in mitotic errors but equivalent DNA cross-linker hypersensitivity, indicating that the cancer phenotype of Fancc-/-;Mad2+/- mice results from error-prone cell division and not exacerbation of the DNA damage repair defect. We found that FANCC enhances targeting of endogenous MAD2 to prometaphase kinetochores, suggesting a mechanism for how FANCC-dependent regulation of the spindle assembly checkpoint prevents chromosome mis-segregation. Whole-exome sequencing revealed similarities between human FA-associated myelodysplastic syndrome (MDS)/AML and the AML that developed in Fancc-/-; Mad2+/- mice. Together, these data illuminate the role of mitotic dysregulation in FA-pathway deficient malignancies in vivo, show how FANCC adjusts the spindle assembly checkpoint rheostat by regulating MAD2 kinetochore targeting in cell cycle-dependent manner, and establish two new mouse models for preclinical studies of AML.

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