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1.
J Clin Oncol ; 41(27): 4433-4442, 2023 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-37433103

RESUMO

PURPOSE: The Standardized Definitions for Efficacy End Points (STEEP) criteria, established in 2007 and updated in 2021 (STEEP 2.0), provide standardized definitions of adjuvant breast cancer (BC) end points. STEEP 2.0 identified a need to separately address end points for neoadjuvant clinical trials. The multidisciplinary NeoSTEEP working group of experts was convened to critically evaluate and align neoadjuvant BC trial end points. METHODS: The NeoSTEEP working group concentrated on neoadjuvant systemic therapy end points in clinical trials with efficacy outcomes-both pathologic and time-to-event survival end points-particularly for registrational intent. Special considerations for subtypes and therapeutic approaches, imaging, nodal staging at surgery, bilateral and multifocal diseases, correlative tissue collection, and US Food and Drug Administration regulatory considerations were contemplated. RESULTS: The working group recommends a preferred definition of pathologic complete response (pCR) as the absence of residual invasive cancer in the complete resected breast specimen and all sampled regional lymph nodes (ypT0/Tis ypN0 per AJCC staging). Residual cancer burden should be a secondary end point to facilitate future assessment of its utility. Alternative end points are needed for hormone receptor-positive disease. Time-to-event survival end point definitions should pay particular attention to the measurement starting point. Trials should include end points originating at random assignment (event-free survival and overall survival) to capture presurgery progression and deaths as events. Secondary end points adapted from STEEP 2.0, which are defined from starting at curative-intent surgery, may also be appropriate. Specification and standardization of biopsy protocols, imaging, and pathologic nodal evaluation are also crucial. CONCLUSION: End points in addition to pCR should be selected on the basis of clinical and biologic aspects of the tumor and the therapeutic agent investigated. Consistent prespecified definitions and interventions are paramount for clinically meaningful trial results and cross-trial comparison.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/cirurgia , Terapia Neoadjuvante/métodos , Projetos de Pesquisa , Intervalo Livre de Progressão
2.
Blood Cancer J ; 12(6): 98, 2022 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-35768410

RESUMO

A wide variety of new therapeutic options for Multiple Myeloma (MM) have recently become available, extending progression-free and overall survival for patients in meaningful ways. However, these treatments are not curative, and patients eventually relapse, necessitating decisions on the appropriate choice of treatment(s) for the next phase of the disease. Additionally, an important subset of MM patients will prove to be refractory to the majority of the available treatments, requiring selection of effective therapies from the remaining options. Immunomodulatory agents (IMiDs), proteasome inhibitors, monoclonal antibodies, and alkylating agents are the major classes of MM therapies, with several options in each class. Patients who are refractory to one agent in a class may be responsive to a related compound or to a drug from a different class. However, rules for selection of alternative treatments in these situations are somewhat empirical and later phase clinical trials to inform those choices are ongoing. To address these issues the NCI Multiple Myeloma Steering Committee formed a relapsed/refractory working group to review optimal treatment choices, timing, and sequencing and provide recommendations. Additional issues considered include the role of salvage autologous stem cell transplantation, risk stratification, targeted approaches for genetic subsets of MM, appropriate clinical trial endpoints, and promising investigational agents. This report summarizes the deliberations of the working group and suggests potential avenues of research to improve the precision, timing, and durability of treatments for Myeloma.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Mieloma Múltiplo , Consenso , Humanos , Mieloma Múltiplo/tratamento farmacológico , Recidiva Local de Neoplasia , Transplante Autólogo
3.
Front Biosci (Landmark Ed) ; 14(1): 297-320, 2009 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-19273068

RESUMO

RNA interference (RNAi) technique has become a valuable tool in biology and biomedicine. In the future, it has the potential for application in many different fields including clinical medicine and agriculture. RNAi is a revolution in biology, representing the natural biological process in which genes are turned off in cells, and a completely new approach to drug discovery and development. This review focuses on the therapeutic potential of RNAi for central nervous system diseases. It gives an overview of the progress which has been made in this field to date, including the application of RNAi in vitro (to neurons) and in vivo (animal disease models) and addresses challenges in developing RNAi-based therapies. This review attempts to describe the future prospective of the clinical application of RNAi for neurodegenerative disorders.


Assuntos
Doenças Neurodegenerativas/terapia , Interferência de RNA , Animais , Humanos , Doenças Neurodegenerativas/genética
4.
Front Biosci ; 13: 2504-15, 2008 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-17981730

RESUMO

The protection of genomic integrity is a major challenge for living cells that are continuously exposed to endogenous and environmental DNA-damaging insults. To cope with the consequences of DNA lesions which interfere with essential DNA-dependent processes including transcription and replication, cells are equipped with an efficient defense mechanism termed the DNA damage response. Its function is to eliminate DNA damage through DNA repair and to remove cells with incurred DNA damage by apoptosis. The DNA damage response has been investigated mainly in proliferating cells, in which the cell cycle machinery is integrated with the DNA damage signaling. Our recent studies suggest that the cell cycle machinery is involved in DNA damage response of postmitotic neurons. Given a high metabolic rate, continuous exposure to oxidative stress and extensive gene transcription activity, the importance of the DNA damage response and the integrated cell cycle signaling for maintaining genomic stability in neurons cannot be overemphasized. The suppression of cell cycle activation is considered neuroprotective, especially in experimental models of stroke. The present review discusses the importance of DNA damage response for postmitotic neurons and the mechanisms of its dysfunction leading to different neurodegenerative disorders. In this regard, a better understanding of the mechanisms underlying DNA damage response in neurons may have important therapeutic implications for different neurodegenerative diseases.


Assuntos
Dano ao DNA , Doenças Neurodegenerativas/embriologia , Neurônios/metabolismo , Fármacos Neuroprotetores/farmacologia , Animais , Apoptose , Ciclo Celular , Proteínas de Ciclo Celular/química , Diferenciação Celular , Reparo do DNA , Instabilidade Genômica , Humanos , Mitose , Doenças Neurodegenerativas/metabolismo , Transdução de Sinais , Transcrição Gênica
5.
Cell Cycle ; 6(3): 318-29, 2007 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-17297309

RESUMO

Increasing evidence indicates that maintenance of neuronal homeostasis involves the activation of the cell cycle machinery in postmitotic neurons. Our recent findings suggest that cell cycle activation is essential for DNA damage-induced neuronal apoptosis. However, whether the cell division cycle also participates in DNA repair and survival of postmitotic, terminally differentiated neurons is unknown. Here, we tested the hypothesis that G(1) phase components contribute to the repair of DNA and are involved in the DNA damage response of postmitotic neurons. In cortical terminally differentiated neurons, treatment with subtoxic concentrations of hydrogen peroxide (H(2)O(2)) caused repairable DNA double strand breaks (DSBs) and the activation of G(1) components of the cell cycle machinery. Importantly, DNA repair was attenuated if cyclin-dependent kinases CDK4 and CDK6, essential elements of G(0) --> G(1) transition, were suppressed. Our data suggest that G(1) cell cycle components are involved in DNA repair and survival of postmitotic neurons.


Assuntos
Ciclo Celular/fisiologia , Reparo do DNA/fisiologia , Neurônios/metabolismo , Animais , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/genética , Células Cultivadas , Quinase 4 Dependente de Ciclina/genética , Quinase 4 Dependente de Ciclina/metabolismo , Quinase 6 Dependente de Ciclina/genética , Quinase 6 Dependente de Ciclina/metabolismo , Quebras de DNA de Cadeia Dupla/efeitos dos fármacos , Dano ao DNA , Reparo do DNA/efeitos dos fármacos , Reparo do DNA/genética , Relação Dose-Resposta a Droga , Citometria de Fluxo , Imunofluorescência , Fase G1/efeitos dos fármacos , Fase G1/genética , Fase G1/fisiologia , Regulação da Expressão Gênica/efeitos dos fármacos , Histonas/metabolismo , Peróxido de Hidrogênio/farmacologia , Immunoblotting , Imunoprecipitação , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/citologia , Neurônios/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , RNA Interferente Pequeno/genética , Ratos , Ratos Sprague-Dawley
6.
Mol Cell Biol ; 24(21): 9580-91, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15485924

RESUMO

La protein binds precursors to 5S rRNA, tRNAs, and other transcripts that contain 3' UUU-OH and also promotes their maturation in the nucleus. Separate from this function, human La has been shown to positively modulate the translation of mRNAs that contain complex 5' regulatory motifs that direct internal initiation of translation. Nonphosphorylated La (npLa) inhibits pre-tRNA processing, while phosphorylation of human La serine-366 (S(366)) promotes pre-tRNA processing. npLa was found specifically associated with a class of mRNAs that have unusually short 5' untranslated regions comprised of terminal oligopyrimidine (5'TOP) tracts and that encode ribosomal proteins and translation elongation factors. Although La S(366) represents a CK2 phosphorylation site, there was no evidence that CK2 phosphorylates it in vivo. We used the CK2-specific inhibitor, 4,5,6,7-tetrabromo-2-azabenzimidazole (TBB), and antisense-mediated knockdown to demonstrate that CK2 is responsible for La S(366) phosphorylation in vivo. Hypophosphorylation was not associated with significant change in total La levels or proteolytic cleavage. Quantitative reverse transcription-PCR revealed increased association of the 5'TOP-mRNA encoding ribosomal protein L37 (rpL37) with La after TBB treatment. Transfection revealed more rpL37 mRNA associated with nonphosphorylatable La A(366) than with La S(366), concomitant with La A(366)-specific shift of a fraction of L37 mRNA off polysomes. The data indicate that CK2 phosphorylates La S(366) in vivo, that this limits 5'TOP mRNA binding, and that increasing npLa leads to greater association with potentially negative effects on TOP mRNA translation. Consistent with data that indicate that phosphorylation reverses negative effects of npLa on tRNA production, the present data suggest that CK2 phosphorylation of La can affect production of the translational machinery.


Assuntos
Caseína Quinase II/metabolismo , Fosfosserina/metabolismo , Pirimidinas/metabolismo , RNA Mensageiro/metabolismo , Ribonucleoproteínas/metabolismo , Proteínas Ribossômicas/genética , Serina/metabolismo , Alanina/genética , Alanina/metabolismo , Apoptose/efeitos dos fármacos , Autoantígenos , Caseína Quinase II/antagonistas & inibidores , Caseína Quinase II/genética , Linhagem Celular , Humanos , Mutação/genética , Fosforilação/efeitos dos fármacos , Polirribossomos/genética , Polirribossomos/metabolismo , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , RNA Mensageiro/genética , Ribonucleoproteínas/antagonistas & inibidores , Ribonucleoproteínas/deficiência , Ribonucleoproteínas/genética , Serina/genética , Triazóis/farmacologia , Antígeno SS-B
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