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1.
J Vis Exp ; (192)2023 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-36912520

RESUMO

Pediatric CNS tumors are responsible for the majority of cancer-related deaths in children and have poor prognoses, despite advancements in chemotherapy and radiotherapy. As many tumors lack efficacious treatments, there is a crucial need to develop more promising therapeutic options, such as immunotherapies; the use of chimeric antigen receptor (CAR) T cell therapy directed against CNS tumors is of particular interest. Cell surface targets such as B7-H3, IL13RA2, and the disialoganglioside GD2 are highly expressed on the surface of several pediatric and adult CNS tumors, raising the opportunity to use CAR T cell therapy against these and other surface targets. To evaluate the repeated locoregional delivery of CAR T cells in preclinical murine models, an indwelling catheter system that recapitulates indwelling catheters currently being used in human clinical trials was established. Unlike stereotactic delivery, the indwelling catheter system allows for repeated dosing without the use of multiple surgeries. This protocol describes the intratumoral placement of a fixed guide cannula that has been used to successfully test serial CAR T cell infusions in orthotopic murine models of pediatric brain tumors. Following orthotopic injection and engraftment of the tumor cells in mice, intratumoral placement of a fixed guide cannula is completed on a stereotactic apparatus and secured with screws and acrylic resin. Treatment cannulas are then inserted through the fixed guide cannula for repeated CAR T cell delivery. Stereotactic placement of the guide cannula can be adjusted to deliver CAR T cells directly into the lateral ventricle or other locations in the brain. This platform offers a reliable mechanism for the preclinical testing of repeated intracranial infusions of CAR T cells and other novel therapeutics for these devastating pediatric tumors.


Assuntos
Neoplasias Encefálicas , Receptores de Antígenos Quiméricos , Animais , Humanos , Camundongos , Neoplasias Encefálicas/patologia , Cânula , Imunoterapia Adotiva/métodos , Linfócitos T , Ensaios Antitumorais Modelo de Xenoenxerto
2.
Orthop J Sports Med ; 11(1): 23259671221137845, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36743733

RESUMO

Background: Objective measures of research influence are being increasingly utilized to evaluate and compare academic faculty. However, traditional bibliometrics, such as the Hirsch index and article citation count, are biased by time-dependent factors and are limited by a lack of field normalization. The relative citation ratio (RCR) is a new field- and time-normalized article-level metric developed by the National Institutes of Health (NIH). Purpose/Hypothesis: The purpose of this study was to evaluate the RCR among fellowship-trained academic sports medicine surgeons and to analyze physician factors associated with RCR values. We hypothesized that the mean RCR score for fellowship-trained academic sports medicine surgery faculty will fall above the NIH standard. Study Design: Cross-sectional study. Methods: A retrospective data analysis was performed using the iCite database for all fellowship-trained sports medicine surgery faculty associated with Accreditation Council for Graduate Medical Education-accredited orthopaedic surgery residency programs in December 2021. In eligible faculty, the mean RCR, weighted RCR, and total publication count were compared by sex, career duration, academic rank, and presence of additional degrees. A mean RCR value of 1.0 is the NIH-funded field-normalized standard. The data herein are presented as the median and interquartile range, in addition to the mean and standard deviation, to account for outliers of the mean and weighted RCR scores. Results: A total of 624 fellowship-trained sports medicine surgery faculty members from 160 orthopaedic surgery residency programs were included in the analysis. Overall, faculty produced impactful research, with a median RCR of 1.6 (interquartile range, 1.0-2.2) and a median weighted RCR of 19.3 (interquartile range, 5.1-69.3). Advanced academic rank and career longevity were associated with increased weighted RCR and total publication count. All subgroups analyzed had an RCR value >1.0. Conclusion: Study findings indicate that fellowship-trained academic sports medicine surgery faculty are highly productive and produce impactful research, as evidenced by the high median RCR value relative to the benchmark NIH RCR value of 1.0.

3.
Cancer Med ; 12(4): 4270-4281, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36151773

RESUMO

BACKGROUND: Patients with relapsed and refractory solid and central nervous system (CNS) tumors have poor outcomes and need novel therapeutic options. Vincristine, irinotecan, and temozolomide (VIT) is a common chemotherapy regimen in relapsed pediatric tumors with an established toxicity profile. Metformin shows preclinical anti-cancer activity through multiple pathways. METHODS: The objective of this Phase I trial was to establish the maximum tolerated dose (MTD) and recommended Phase II dose (RP2D) of metformin in combination with VIT in children with relapsed and refractory solid and CNS tumors. A 3 + 3 design was used to test the addition of metformin at five dose levels (666, 999, 1333, 1666, and 2000 mg/m2 /day). Therapy toxicity, pharmacokinetics, and radiologic response to treatment were evaluated. RESULTS: Twenty-six patients (median age 13 years, range 2-18 years) were enrolled with 22 evaluable for toxicity. The most common diagnoses were Ewing sarcoma (n = 8), rhabdomyosarcoma (n = 3) and atypical teratoid/rhabdoid tumor (n = 3). The MTD was exceeded at Dose Level 5 due to two dose-limiting toxicities; both were Grade 3 diarrhea requiring prolonged hospitalization and intravenous fluids. The MTD was not determined due to study closure with less than six patients enrolled at Dose Level 4. Frequently observed toxicities were gastrointestinal (most notably diarrhea) and hematologic. Amongst 16 patients evaluable for best overall response, there was one complete response (Ewing sarcoma), three partial responses (Ewing sarcoma, glioblastoma multiforme, and alveolar rhabdomyosarcoma), and five patients with stable disease. CONCLUSIONS: The MTD of VIT with metformin was not determined due to premature study closure. We recommend an RP2D of Dose Level 4, 1666 mg/m2 /day. Radiographic responses were seen in multiple tumor types. Further evaluation for efficacy could be investigated in a Phase II trial.


Assuntos
Neoplasias do Sistema Nervoso Central , Metformina , Neoplasias , Sarcoma de Ewing , Criança , Humanos , Pré-Escolar , Adolescente , Irinotecano/efeitos adversos , Temozolomida/uso terapêutico , Vincristina/uso terapêutico , Sarcoma de Ewing/tratamento farmacológico , Metformina/uso terapêutico , Camptotecina , Dacarbazina , Neoplasias/tratamento farmacológico , Neoplasias/etiologia , Neoplasias do Sistema Nervoso Central/tratamento farmacológico , Dose Máxima Tolerável , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Recidiva Local de Neoplasia/tratamento farmacológico
4.
Artigo em Inglês | MEDLINE | ID: mdl-36307212

RESUMO

Angiosarcomas are rare, malignant soft tissue tumors in children that arise in a wide range of anatomical locations and have limited targeted therapies available. Here, we report a rare case of a pediatric angiosarcoma (pAS) with Li-Fraumeni syndrome (LFS) expressing a novel NOTCH1-ROS1 gene fusion. Although both NOTCH1 and ROS1 are established proto-oncogenes, our study is the first to describe the mechanistic role of NOTCH1-ROS1 fusion arising via intrachromosomal rearrangement. NOTCH1-ROS1 displayed potent neoplastic transformation propensity in vitro, and harbors tumorigenic potential in vivo, where it induced oncogenic activation of the MAPK, PI3K/mTOR, and JAK-STAT signaling pathways in a murine allograft model. We found an unexpected contribution of the NOTCH1 extracellular region in mediating NOTCH1-ROS1 activation and oncogenic function, highlighting the contribution of both NOTCH1 and ROS1 fusion partners in driving tumorigenicity. Interestingly, neither membrane localization nor fusion protein dimerization were found to be essential for NOTCH1-ROS1 fusion oncogenicity. To target NOTCH1-ROS1-driven tumors, we tested both NOTCH1-directed inhibitors and ROS1-targeted tyrosine kinase inhibitors (TKI) in heterologous models (NIH3T3, Ba/F3). Although NOTCH1 inhibitors did not suppress NOTCH1-ROS1-driven oncogenic growth, we found that oral entrectinib treatment effectively suppressed the growth of NOTCH-ROS1-driven tumors. Taken together, we report the first known pAS case with a novel NOTCH1-ROS1 alteration along with a detailed report on the function and therapeutic targeting of NOTCH1-ROS1. Our study highlights the importance of genomic profiling of rare cancers such as pAS to reveal actionable drivers and improve patient outcomes.


Assuntos
Hemangiossarcoma , Proteínas Tirosina Quinases , Criança , Humanos , Camundongos , Animais , Proteínas Tirosina Quinases/genética , Proteínas Tirosina Quinases/metabolismo , Hemangiossarcoma/tratamento farmacológico , Hemangiossarcoma/genética , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas/genética , Células NIH 3T3 , Fusão Gênica , Receptor Notch1/genética
5.
J Immunother Cancer ; 10(9)2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36167467

RESUMO

BACKGROUND: Pediatric brain tumors are the leading cause of cancer death in children with an urgent need for innovative therapies. Glypican 2 (GPC2) is a cell surface oncoprotein expressed in neuroblastoma for which targeted immunotherapies have been developed. This work aimed to characterize GPC2 expression in pediatric brain tumors and develop an mRNA CAR T cell approach against this target. METHODS: We investigated GPC2 expression across a cohort of primary pediatric brain tumor samples and cell lines using RNA sequencing, immunohistochemistry, and flow cytometry. To target GPC2 in the brain with adoptive cellular therapies and mitigate potential inflammatory neurotoxicity, we used optimized mRNA to create transient chimeric antigen receptor (CAR) T cells. We developed four mRNA CAR T cell constructs using the highly GPC2-specific fully human D3 single chain variable fragment for preclinical testing. RESULTS: We identified high GPC2 expression across multiple pediatric brain tumor types including medulloblastomas, embryonal tumors with multilayered rosettes, other central nervous system embryonal tumors, as well as definable subsets of highly malignant gliomas. We next validated and prioritized CAR configurations using in vitro cytotoxicity assays with GPC2-expressing neuroblastoma cells, where the light-to-heavy single chain variable fragment configurations proved to be superior. We expanded the testing of the two most potent GPC2-directed CAR constructs to GPC2-expressing medulloblastoma and high-grade glioma cell lines, showing significant GPC2-specific cell death in multiple models. Finally, biweekly locoregional delivery of 2-4 million GPC2-directed mRNA CAR T cells induced significant tumor regression in an orthotopic medulloblastoma model and significantly prolonged survival in an aggressive orthotopic thalamic diffuse midline glioma xenograft model. No GPC2-directed CAR T cell related neurologic or systemic toxicity was observed. CONCLUSION: Taken together, these data show that GPC2 is a highly differentially expressed cell surface protein on multiple malignant pediatric brain tumors that can be targeted safely with local delivery of mRNA CAR T cells, laying the framework for the clinical translation of GPC2-directed immunotherapies for pediatric brain tumors.


Assuntos
Neoplasias Encefálicas , Neoplasias Cerebelares , Glioma , Meduloblastoma , Neuroblastoma , Receptores de Antígenos Quiméricos , Anticorpos de Cadeia Única , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/terapia , Linhagem Celular Tumoral , Criança , Glioma/genética , Glioma/terapia , Glipicanas/genética , Humanos , Neuroblastoma/patologia , Proteínas Oncogênicas , RNA Mensageiro/genética , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Alzheimers Dement (N Y) ; 8(1): e12334, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35910668

RESUMO

Introduction: Retromer complex proteins are decreased in Down syndrome (DS) brains and correlate inversely with brain amyloidosis. However, whether retromer dysfunction contributes to the amyloid beta (Aß) and tau neuropathology of DS remains unknown. Methods: Human trisomic induced Pluripotent Stem Cells (iPSCs) and isogenic controls were differentiated into forebrain neurons, and changes in retromer proteins, tau phosphorylated epitopes, and Aß levels were assessed in euploid and trisomic neurons using western blot and enzyme-linked immunosorbent assay (ELISA). Genetic overexpression and pharmacological retromer stabilization were used to determine the functional role of the retromer complex system in modulating amyloid and tau pathology. Results: Trisomic neurons developed age-dependent retromer core protein deficiency associated with accumulation of Aß peptides and phosphorylated tau isoforms. Enhancing retromer function through overexpression or pharmacological retromer stabilization reduced amyloid and tau pathology in trisomic neurons. However, the effect was greater using a pharmacological approach, suggesting that targeting the complex stability may be more effective in addressing this neuropathology in DS. Discussion: Our results demonstrate that the retromer complex is directly involved in the development of the neuropathologic phenotype in DS, and that pharmacological stabilization of the complex should be considered as a novel therapeutic tool in people with DS.

7.
N Am Spine Soc J ; 11: 100143, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35928806

RESUMO

Background: Publication metrics have been traditionally used to compare research productivity amongst academic faculty. However, traditional bibliometrics lack field-normalization and are often biased towards time-dependent publication factors. The National Institutes of Health (NIH) has developed a new, field-normalized, article-level metric, known as the "relative citation ratio" (RCR), that can be used to make accurate self, departmental, and cross-specialty comparisons of research productivity. This study evaluates the use of the RCR amongst academic orthopedic spine surgery faculty and analyzes physician factors associated with RCR values. Methods: A retrospective data analysis was performed using the iCite database for all fellowship trained orthopedic spine surgery (OSS) faculty associated with Accreditation Council for Graduate Medical Education (ACGME)-accredited orthopedic surgery residency program. Mean RCR, weighted RCR, and total publication count were compared by sex, career duration, academic rank, and presence of additional degrees. A value of 1.0 is the NIH-funded field-normalized standard. Student t-tests were used for two-group analyses whereas the analysis of variance tests (ANOVA) was used for between-group comparisons of three or more subgroups. Statistical significance was achieved at P < 0.05. Results: A total of 502 academic OSS faculty members from 159 institutions were included in the analysis. Overall, OSS faculty were highly productive, with a median RCR of 1.62 (IQR 1.38-2.32) and a median weighted RCR of 68.98 (IQR 21.06-212.70). Advancing academic rank was associated with weighted RCR, career longevity was associated with mean RCR score, and male sex was associated with having increased mean and weighted RCR scores. All subgroups analyzed had an RCR value above 1.0. Conclusions: Academic orthopedic spine surgery faculty produce impactful research as evidenced by the high median RCR relative to the standard value set by the NIH of 1.0. Our data can be used to evaluate research productivity in the orthopedic spine community.

8.
Cureus ; 14(6): e26231, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35898372

RESUMO

The metacarpophalangeal (MCP) joint is surrounded by various structures critical to its stability and function. Though the ligamentous injury to the digits is common, rupture of the metacarpophalangeal collateral ligament and a sagittal band of the same finger is not well represented in the literature. We report a chronic case of a concurrent metacarpophalangeal collateral ligament and sagittal band injury. Though surgery would have been the most appropriate treatment soon after the injury, restrictions on elective procedures due to the COVID-19 pandemic precluded surgical treatment. The patient was alternatively treated with buddy tape, and a close follow-up was done. This is the first reported case of a concurrent metacarpophalangeal collateral ligament, and sagittal band injury successfully treated using nonoperative management.

9.
Ann Neurol ; 91(4): 561-567, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35150166

RESUMO

Retromer deficiency is reported in Down syndrome and correlates with amyloidosis, however, its association with tau neuropathology remains unclear. Down syndrome and control brain tissues were evaluated for phosphorylated tau, tau modulators, and cathepsin-D activity. Several kinases and phosphatase PP2A were unchanged, but tau phosphorylation was elevated, and cathepsin-D activity decreased in aged patients with Down syndrome. Retromer proteins positively associated with soluble tau, whereas pathogenic tau negatively correlated with retromer proteins and cathepsin-D activity. Retromer deficiency and consequent reduction of cathepsin-D activity may contribute to pathogenic tau accumulation, thus, retromer represents a viable therapeutic target against tau pathology in Down syndrome. ANN NEUROL 2022;91:561-567.


Assuntos
Síndrome de Down , Proteínas tau , Idoso , Catepsinas/metabolismo , Síndrome de Down/metabolismo , Humanos , Neuropatologia , Fosforilação , Proteínas tau/metabolismo
10.
Viruses ; 13(7)2021 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-34372550

RESUMO

Persistent hepatitis B virus (HBV) infection remains a serious medical problem worldwide, with an estimated global burden of 257 million carriers. Prophylactic and therapeutic interventions, in the form of a vaccine, immunomodulators, and nucleotide and nucleoside analogs, are available. Vaccination, however, offers no therapeutic benefit to chronic sufferers and has had a limited impact on infection rates. Although immunomodulators and nucleotide and nucleoside analogs have been licensed for treatment of chronic HBV, cure rates remain low. Transcription activator-like effector nucleases (TALENs) designed to bind and cleave viral DNA offer a novel therapeutic approach. Importantly, TALENs can target covalently closed circular DNA (cccDNA) directly with the potential of permanently disabling this important viral replicative intermediate. Potential off-target cleavage by engineered nucleases leading to toxicity presents a limitation of this technology. To address this, in the context of HBV gene therapy, existing TALENs targeting the viral core and surface open reading frames were modified with second- and third-generation FokI nuclease domains. As obligate heterodimers these TALENs prevent target cleavage as a result of FokI homodimerization. Second-generation obligate heterodimeric TALENs were as effective at silencing viral gene expression as first-generation counterparts and demonstrated an improved specificity in a mouse model of HBV replication.


Assuntos
Vírus da Hepatite B/genética , Hepatite B/tratamento farmacológico , Nucleases dos Efetores Semelhantes a Ativadores de Transcrição/genética , Animais , Animais não Endogâmicos , Antivirais/uso terapêutico , Linhagem Celular , Vírus de DNA/genética , DNA Circular , DNA Viral/genética , Desoxirribonucleases de Sítio Específico do Tipo II/genética , Desoxirribonucleases de Sítio Específico do Tipo II/metabolismo , Modelos Animais de Doenças , Endonucleases/genética , Feminino , Terapia Genética/métodos , Células HEK293 , Células Hep G2 , Hepatite B/genética , Hepatite B/imunologia , Hepatite B Crônica/genética , Hepatite B Crônica/virologia , Humanos , Camundongos , Nucleases dos Efetores Semelhantes a Ativadores de Transcrição/uso terapêutico , Replicação Viral/genética
11.
JCO Glob Oncol ; 7: 1251-1259, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34351814

RESUMO

PURPOSE: Belize has one of the highest cervical cancer burdens among Latin American and Caribbean countries, despite the implementation of national policies to increase access to prevention and treatment services. This study evaluates the policies, infrastructure, and workforce of the cervical cancer management system in Belize to inform capacity building efforts. METHODS: In 2018, health facility assessments were conducted across all six districts of Belize at the national pathology facility and 12 public facilities identified as critical to cervical cancer control. Human and infrastructure resource availability and existing policies related to cervical cancer screening and treatment services were assessed through a structured instrument. RESULTS: The public cervical cancer screening workforce in Belize consists of 75 primary care nurses and physicians-one per 1,076 screening-eligible women, with 44% conducting rural outreach. All districts have at least one screening facility, but 50% perform screening services only once per week. Colposcopy and loop electrical excision procedures are available in three and four districts, respectively; radical hysterectomy and chemotherapy are available in two districts; and radiation therapy is unavailable. Of essential pathology equipment, 38.5% were present and functional, 23% were present but nonfunctional, and 38.5% were unavailable. Additionally, 35% of supplies were unavailable at the time of assessment, and 75% were unavailable at least once in the 12 months before assessment. CONCLUSION: Public-sector cervical cancer management services differ among districts of Belize, with tertiary service availability concentrated in the largest district. Screening, outreach, and pathology are limited mostly by resource availability. This study characterizes the current capacity of services in Belize and pinpoints health system components for future investment and capacity-building efforts.


Assuntos
Neoplasias do Colo do Útero , Belize , Colposcopia , Atenção à Saúde , Detecção Precoce de Câncer , Feminino , Humanos , Gravidez , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/epidemiologia , Neoplasias do Colo do Útero/prevenção & controle
12.
Adv Drug Deliv Rev ; 168: 134-146, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32485207

RESUMO

Chronic infection with the hepatitis B virus (HBV) remains a significant worldwide medical problem. While diseases caused by HIV infection, tuberculosis and malaria are on the decline, new cases of chronic hepatitis B are on the rise. Because often fatal complications of cirrhosis and hepatocellular carcinoma are associated with chronic hepatitis B, the need for a cure is as urgent as ever. Currently licensed therapeutics fail to eradicate the virus and this is attributable to persistence of the viral replication intermediate comprising covalently closed circular DNA (cccDNA). Elimination or inactivation of the viral cccDNA is thus a goal of research aimed at hepatitis B cure. The ability to engineer nucleases that are capable of specific cleavage of a DNA sequence now provides the means to disable cccDNA permanently. The scientific literature is replete with many examples of using designer zinc finger nucleases (ZFNs), transcription activator-like effector nucleases (TALENs) and RNA-guided endonucleases (RGENs) to inactivate HBV. However, important concerns about safety, dose control and efficient delivery need to be addressed before the technology is employed in a clinical setting. Use of in vitro transcribed mRNA to express therapeutic gene editors goes some way to overcoming these concerns. The labile nature of RNA limits off-target effects and enables dose control. Compatibility with hepatotropic non-viral vectors is convenient for the large scale preparation that will be required for advancing gene editing as a mode of curing chronic hepatitis B.


Assuntos
Terapia Genética/métodos , Hepatite B Crônica/genética , Hepatite B Crônica/terapia , RNA Mensageiro/administração & dosagem , Antivirais/uso terapêutico , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Relação Dose-Resposta a Droga , Edição de Genes , Vetores Genéticos/administração & dosagem , Vacinas contra Hepatite B/administração & dosagem , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/prevenção & controle , Nanopartículas/química , Ribonucleases/administração & dosagem , Nucleases dos Efetores Semelhantes a Ativadores de Transcrição/metabolismo , Nucleases de Dedos de Zinco/metabolismo
13.
Pediatr Blood Cancer ; 67(7): e28370, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32386107

RESUMO

BACKGROUND: The combination of gemcitabine and docetaxel is often used to treat patients with recurrent sarcoma. Nab-paclitaxel is a taxane modified to improve drug exposure and increase intratumoral accumulation and, in combination with gemcitabine, is standard therapy for pancreatic cancer. Applying the dosages and schedule used for pancreatic cancer, we performed a phase II trial to assess the response rate of gemcitabine and nab-paclitaxel in patients with relapsed Ewing sarcoma. PROCEDURE: Using a Simon's two-stage design to identify a response rate of ≥ 35%, patients received nab-paclitaxel 125 mg/m2 followed by gemcitabine 1000 mg/m2 i.v. on days 1, 8, and 15 of four-week cycles. Immunohistochemical analysis of archival tissue was performed to identify possible biomarkers of response. RESULTS: Eleven patients from four institutions enrolled, with a median age of 22 years (range, 14-27). Patients were heavily pretreated (median 3 prior regimens, range, 1-7). Thirty-five cycles were administered (median 2, range, 1-8). Accrual was stopped after 11 patients, due to only one confirmed partial response. Two other patients had partial responses after two cycles, but withdrew because of adverse effects or progression before confirmation of continued response. The predominant toxicity was myelosuppression, and four (36%) patients were removed due to hematologic toxicity despite pegfilgrastim and dose reductions. Expression of secreted protein, acidic and rich in cysteine (SPARC) and CAV-1 in archival tumors was not predictive of clinical benefit in this small cohort of patients. CONCLUSIONS: In patients with heavily pretreated Ewing sarcoma, the confirmed response rate of 9% was similar to multi-institutional studies of gemcitabine and docetaxel.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Ósseas/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Sarcoma de Ewing/tratamento farmacológico , Adolescente , Adulto , Albuminas/administração & dosagem , Neoplasias Ósseas/patologia , Criança , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Feminino , Seguimentos , Humanos , Masculino , Recidiva Local de Neoplasia/patologia , Paclitaxel/administração & dosagem , Prognóstico , Sarcoma de Ewing/patologia , Adulto Jovem , Gencitabina
14.
Pediatr Blood Cancer ; 65(9): e27224, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29856514

RESUMO

BACKGROUND: Acute lymphoblastic leukemia (ALL) remains a major cause of death in children. AMP-activated protein kinase (AMPK) affects the unfolded protein response (UPR), leading to increased vulnerability to endoplasmic reticulum (ER) stress in ALL cells. In vitro, metformin causes ALL cell death via AMPK-mediated inhibition of the UPR. It was evaluated whether ER stress could be induced in relapsed ALL through a phase I study investigating the safety and feasibility of metformin in combination with relapse induction chemotherapy. PROCEDURE: Metformin was administered twice daily for 28 days in addition to vincristine, dexamethasone, PEG-asparaginase and doxorubicin (VXLD). Dose escalation of metformin was evaluated using a 3+3 design. Pharmacokinetics (PK), pharmacodynamic (PD) evaluation of the AMPK and ER stress/UPR pathways, and treatment response were assessed. RESULTS: Fourteen patients were enrolled; all were evaluable for toxicity. The recommended phase 2 dose (RP2D) was Dose level 2, 1,000 mg/m2 /day. A single dose-limiting toxicity (DLT), hypoglycemia with acidosis, was observed at the RP2D and two DLTs, diarrhea and acidosis, were observed at Dose Level 3. Nine patients were evaluable for response as defined by the protocol, receiving at least 85% of planned metformin doses. Five complete remissions, one partial response, and one stable disease were observed. PD evaluation showed induction of ER stress, activation of AMPK, and inhibition of the UPR. CONCLUSIONS: The VXLD with metformin was tolerable with a RP2D for metformin of 1,000 mg/m2 /day and yielded responses in a heavily pretreated population. ER stress was induced and toxicities attributable to metformin occurred in all dose levels.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Terapia de Salvação , Proteínas Quinases Ativadas por AMP/antagonistas & inibidores , Adolescente , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Asparaginase/administração & dosagem , Asparaginase/efeitos adversos , Criança , Pré-Escolar , Dexametasona/administração & dosagem , Dexametasona/efeitos adversos , Relação Dose-Resposta a Droga , Doxorrubicina/administração & dosagem , Doxorrubicina/efeitos adversos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Feminino , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Dose Máxima Tolerável , Metformina/administração & dosagem , Metformina/efeitos adversos , Metformina/farmacologia , Proteínas de Neoplasias/antagonistas & inibidores , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/efeitos adversos , Recidiva , Resultado do Tratamento , Resposta a Proteínas não Dobradas/efeitos dos fármacos , Vincristina/administração & dosagem , Vincristina/efeitos adversos , Adulto Jovem
15.
Oncotarget ; 8(49): 84697-84713, 2017 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-29156677

RESUMO

Pediatric low-grade gliomas (PLGGs) are frequently associated with activating BRAF gene fusions, such as KIAA1549-BRAF, that aberrantly drive the mitogen activated protein kinase (MAPK) pathway. Although RAF inhibitors (RAFi) have been proven effective in BRAF-V600E mutant tumors, we have previously shown how the KIAA1549-BRAF fusion can be paradoxically activated by RAFi. While newer classes of RAFi, such as PLX8394, have now been shown to inhibit MAPK activation by KIAA1549-BRAF, we sought to identify alternative MAPK pathway targeting strategies using clinically relevant MEK inhibitors (MEKi), along with potential escape mechanisms of acquired resistance to single-agent MAPK pathway therapies. We demonstrate effectiveness of multiple MEKi against diverse BRAF-fusions with novel N-terminal partners, with trametinib being the most potent. However, resistance to MEKi or PLX8394 develops via increased RTK expression causing activation of PI3K/mTOR pathway in BRAF-fusion expressing resistant clones. To circumvent acquired resistance, we show potency of combinatorial targeting with trametinib and everolimus, an mTOR inhibitor (mTORi) against multiple BRAF-fusions. While single-agent mTORi and MEKi PLGG clinical trials are underway, our study provides preclinical rationales for using MEKi and mTORi combinatorial therapy to stave off or prevent emergent drug-resistance in BRAF-fusion driven PLGGs.

16.
Cancer Med ; 5(2): 294-303, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26714427

RESUMO

Targeted kinase inhibitors and camptothecins have shown preclinical and clinical activity in several cancers. This trial evaluated the maximum tolerated dose (MTD) and dose-limiting toxicities of sorafenib and topotecan administered orally in pediatric patients with relapsed solid tumors. Sorafenib was administered twice daily and topotecan once daily on days 1-5 and 8-12 of each 28-day course. The study utilized a standard 3 + 3 dose escalation design. Three dose levels (DL) were evaluated: (1) sorafenib 150 mg/m(2) and topotecan 1 mg/m(2) ; (2) sorafenib 150 mg/m(2) and topotecan 1.4 mg/m(2) ; and (3) sorafenib 200 mg/m(2) and topotecan 1.4 mg/m(2) . Pharmacokinetics were ascertained and treatment response assessed. Thirteen patients were enrolled. DL2 was the determined MTD. Grade 4 thrombocytopenia delaying therapy for >7 days was observed in one of six patients on DL2, and grade 4 neutropenia that delayed therapy in two of three patients on DL3. A patient with preexisting cardiac failure controlled with medication developed a transient drop in the left ventricular ejection fraction that improved when sorafenib was withheld. Sorafenib exposure with or without topotecan was comparable, and the concentration-time profiles for topotecan alone and in combination with sorafenib were similar. One objective response was noted in a patient with fibromatosis. We determined MTD to be sorafenib 150 mg/m(2) twice daily orally on days 1-28 combined with topotecan 1.4 mg/m(2) once daily on days 1-5 and 8-12. While these doses are 1 DL below the MTD of the agents individually, pharmacokinetic studies suggested adequate drug exposure without drug interactions. The combination had limited activity in the population studied.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias/tratamento farmacológico , Niacinamida/análogos & derivados , Compostos de Fenilureia/uso terapêutico , Inibidores de Proteínas Quinases/uso terapêutico , Administração Oral , Adolescente , Antineoplásicos/farmacologia , Criança , Esquema de Medicação , Monitoramento de Medicamentos , Feminino , Humanos , Masculino , Dose Máxima Tolerável , Neoplasias/diagnóstico , Niacinamida/farmacologia , Niacinamida/uso terapêutico , Compostos de Fenilureia/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Sorafenibe , Resultado do Tratamento
17.
Cancer Prev Res (Phila) ; 8(10): 879-87, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25873370

RESUMO

Preclinical, epidemiologic, and prior clinical trial data suggest that green tea catechins (GTC) may reduce prostate cancer risk. We conducted a placebo-controlled, randomized clinical trial of Polyphenon E (PolyE), a proprietary mixture of GTCs, containing 400 mg (-)-epigallocatechin-3-gallate (EGCG) per day, in 97 men with high-grade prostatic intraepithelial neoplasia (HGPIN) and/or atypical small acinar proliferation (ASAP). The primary study endpoint was a comparison of the cumulative one-year prostate cancer rates on the two study arms. No differences in the number of prostate cancer cases were observed: 5 of 49 (PolyE) versus 9 of 48 (placebo), P = 0.25. A secondary endpoint comparing the cumulative rate of prostate cancer plus ASAP among men with HGPIN without ASAP at baseline, revealed a decrease in this composite endpoint: 3 of 26 (PolyE) versus 10 of 25 (placebo), P < 0.024. This finding was driven by a decrease in ASAP diagnoses on the Poly E (0/26) compared with the placebo arm (5/25). A decrease in serum prostate-specific antigen (PSA) was observed on the PolyE arm [-0.87 ng/mL; 95% confidence intervals (CI), -1.66 to -0.09]. Adverse events related to the study agent did not significantly differ between the two study groups. Daily intake of a standardized, decaffeinated catechin mixture containing 400 mg EGCG per day for 1 year accumulated in plasma and was well tolerated but did not reduce the likelihood of prostate cancer in men with baseline HGPIN or ASAP.


Assuntos
Antineoplásicos/uso terapêutico , Catequina/análogos & derivados , Neoplasia Prostática Intraepitelial/patologia , Neoplasias da Próstata/prevenção & controle , Adulto , Idoso , Idoso de 80 Anos ou mais , Catequina/uso terapêutico , Progressão da Doença , Método Duplo-Cego , Humanos , Masculino , Pessoa de Meia-Idade , Chá
18.
Am J Hum Genet ; 94(1): 23-32, 2014 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-24360809

RESUMO

Mutations in interferon regulatory factor 6 (IRF6) account for ∼70% of cases of Van der Woude syndrome (VWS), the most common syndromic form of cleft lip and palate. In 8 of 45 VWS-affected families lacking a mutation in IRF6, we found coding mutations in grainyhead-like 3 (GRHL3). According to a zebrafish-based assay, the disease-associated GRHL3 mutations abrogated periderm development and were consistent with a dominant-negative effect, in contrast to haploinsufficiency seen in most VWS cases caused by IRF6 mutations. In mouse, all embryos lacking Grhl3 exhibited abnormal oral periderm and 17% developed a cleft palate. Analysis of the oral phenotype of double heterozygote (Irf6(+/-);Grhl3(+/-)) murine embryos failed to detect epistasis between the two genes, suggesting that they function in separate but convergent pathways during palatogenesis. Taken together, our data demonstrated that mutations in two genes, IRF6 and GRHL3, can lead to nearly identical phenotypes of orofacial cleft. They supported the hypotheses that both genes are essential for the presence of a functional oral periderm and that failure of this process contributes to VWS.


Assuntos
Anormalidades Múltiplas/patologia , Fenda Labial/patologia , Fissura Palatina/patologia , Cistos/patologia , Proteínas de Ligação a DNA/genética , Lábio/anormalidades , Fatores de Transcrição/genética , Anormalidades Múltiplas/genética , Alelos , Animais , Fenda Labial/genética , Fissura Palatina/genética , Cistos/genética , Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Genótipo , Humanos , Hibridização Genética , Fatores Reguladores de Interferon/genética , Fatores Reguladores de Interferon/metabolismo , Lábio/patologia , Camundongos , Camundongos Knockout , Mutação de Sentido Incorreto , Linhagem , Fenótipo , Análise de Sequência de DNA , Fatores de Transcrição/metabolismo , Peixe-Zebra/embriologia , Peixe-Zebra/genética
19.
Behav Brain Res ; 259: 242-6, 2014 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-24269270

RESUMO

Both the serotonin and glutamate systems have been implicated in the pathophysiology of schizophrenia, as well as in the mechanism of action of antipsychotic drugs. Psychedelic drugs act through the serotonin 2A receptor (5-HT2AR), and elicit a head-twitch response (HTR) in mice, which directly correlates to 5-HT2AR activation and is absent in 5-HT2AR knockout mice. The precise mechanism of this response remains unclear, but both an intrinsic cortico-cortical pathway and a thalamo-cortical pathway involving glutamate release have been proposed. Here, we used a genetic model of NMDAR hypofunction, the serine racemase knockout (SRKO) mouse, to explore the role of glutamatergic transmission in regulating 5-HT2AR-mediated cellular and behavioral responses. SRKO mice treated with the 5-HT2AR agonist (±)-2,5-dimethoxy-4-iodoamphetamine (DOI) showed a clearly diminished HTR and lower induction of c-fos mRNA. These altered functional responses in SRKO mice were not associated with changes in cortical or hippocampal 5-HT levels or in 5-HT2AR and metabotropic glutamate-2 receptor (mGluR2) mRNA and protein expression. Together, these findings suggest that D-serine-dependent NMDAR activity is involved in mediating the cellular and behavioral effects of 5-HT2AR activation.


Assuntos
Anfetaminas/farmacologia , Comportamento Animal/efeitos dos fármacos , Racemases e Epimerases/deficiência , Agonistas do Receptor de Serotonina/farmacologia , Animais , Comportamento Animal/fisiologia , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Maleato de Dizocilpina/farmacologia , Relação Dose-Resposta a Droga , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/genética , Movimentos da Cabeça/efeitos dos fármacos , Movimentos da Cabeça/fisiologia , Ácido Hidroxi-Indolacético/metabolismo , Camundongos , Camundongos Knockout , Proteínas Proto-Oncogênicas c-fos/genética , Proteínas Proto-Oncogênicas c-fos/metabolismo , RNA Mensageiro/metabolismo , Racemases e Epimerases/genética , Receptores de N-Metil-D-Aspartato/metabolismo , Serotonina/metabolismo
20.
Cancer Epidemiol Biomarkers Prev ; 22(9): 1520-8, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23833122

RESUMO

BACKGROUND: Rare, inherited mutations account for 5% to 10% of all prostate cancer cases. However, to date, few causative mutations have been identified. METHODS: To identify rare mutations for prostate cancer, we conducted whole-exome sequencing (WES) in multiple kindreds (n = 91) from 19 hereditary prostate cancer (HPC) families characterized by aggressive or early-onset phenotypes. Candidate variants (n = 130) identified through family- and bioinformatics-based filtering of WES data were then genotyped in an independent set of 270 HPC families (n = 819 prostate cancer cases; n = 496 unaffected relatives) for replication. Two variants with supportive evidence were subsequently genotyped in a population-based case-control study (n = 1,155 incident prostate cancer cases; n = 1,060 age-matched controls) for further confirmation. All participants were men of European ancestry. RESULTS: The strongest evidence was for two germline missense variants in the butyrophilin-like 2 (BTNL2) gene (rs41441651, p.Asp336Asn and rs28362675, p.Gly454Cys) that segregated with affection status in two of the WES families. In the independent set of 270 HPC families, 1.5% (rs41441651; P = 0.0032) and 1.2% (rs28362675; P = 0.0070) of affected men, but no unaffected men, carried a variant. Both variants were associated with elevated prostate cancer risk in the population-based study (rs41441651: OR, 2.7; 95% CI, 1.27-5.87; P = 0.010; rs28362675: OR, 2.5; 95% CI, 1.16-5.46; P = 0.019). CONCLUSIONS: Results indicate that rare BTNL2 variants play a role in susceptibility to both familial and sporadic prostate cancer. IMPACT: Results implicate BTNL2 as a novel prostate cancer susceptibility gene.


Assuntos
Mutação em Linhagem Germinativa , Glicoproteínas de Membrana/genética , Mutação de Sentido Incorreto , Neoplasias da Próstata/genética , Idoso , Butirofilinas , Estudos de Casos e Controles , Predisposição Genética para Doença , Genótipo , Humanos , Masculino , Glicoproteínas de Membrana/metabolismo , Pessoa de Meia-Idade , Neoplasias da Próstata/metabolismo , Fatores de Risco
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