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1.
Cell Commun Signal ; 22(1): 105, 2024 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-38331801

RESUMO

The current scientific literature has extensively explored the potential role of proteasome inhibitors (PIs) in the NF-κB pathway of leukemia and lymphoma. The ubiquitin-proteasome system (UPS) is a critical component in regulating protein degradation in eukaryotic cells. PIs, such as BTZ, are used to target the 26S proteasome in hematologic malignancies, resulting in the prevention of the degradation of tumor suppressor proteins, the activation of intrinsic mitochondrial-dependent cell death, and the inhibition of the NF-κB signaling pathway. NF-κB is a transcription factor that plays a critical role in the regulation of apoptosis, cell proliferation, differentiation, inflammation, angiogenesis, and tumor migration. Despite the successful use of PIs in various hematologic malignancies, there are limitations such as resistant to these inhibitors. Some reports suggest that PIs can induce NF-κB activation, which increases the survival of malignant cells. This article discusses the various aspects of PIs' effects on the NF-κB pathway and their limitations. Video Abstract.


Assuntos
Neoplasias Hematológicas , Leucemia , Linfoma , Humanos , Inibidores de Proteassoma/farmacologia , Inibidores de Proteassoma/uso terapêutico , NF-kappa B/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Leucemia/tratamento farmacológico , Linfoma/tratamento farmacológico , Apoptose
2.
Mol Biol Rep ; 51(1): 865, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39073611

RESUMO

BACKGROUND: Treating Acute Myeloid Leukemia (AML) and Acute Lymphoblastic Leukemia (ALL) is difficult due to high relapse rates and drug resistance. Tumorigenesis is largely dependent on disruption of the cell cycle progression. While the role of Cell Division Cycle 27 (CDC27) in the anaphase-promoting complex/cyclosome is well-known, its significance in the pathophysiology of acute leukemia and its potential as a biomarker are less well understood. METHODS AND RESULTS: This case-control study used samples from 100 leukemia patients (50 with ALL and 50 with AML) at Shariati Hospital in Tehran, Iran, along with 50 healthy individuals. The expression of CDC27 was analyzed using quantitative real-time PCR (RQ-PCR). Statistical analysis was done using the nonparametric Mann-Whitney U test. The results showed that AML and ALL patients had significantly higher levels of CDC27 expression compared to the control group. Although a weak correlation between CDC27 expression and hematological parameters was found, there was no significant correlation with sample type, demographics, clinical variables or prognosis. CONCLUSIONS: This study highlights the potential of CDC27 as an oncogene, as well as a possible prognostic and diagnostic marker in acute leukemias. It suggests that CDC27 could be a valuable biomarker or therapeutic target in the treatment of AML and ALL.


Assuntos
Biomarcadores Tumorais , Leucemia Mieloide Aguda , Leucemia-Linfoma Linfoblástico de Células Precursoras , Humanos , Masculino , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Feminino , Adulto , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Estudos de Casos e Controles , Pessoa de Meia-Idade , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Adolescente , Prognóstico , Adulto Jovem , Irã (Geográfico) , Regulação Leucêmica da Expressão Gênica , Idoso , Criança , Subunidade Apc3 do Ciclossomo-Complexo Promotor de Anáfase
3.
Mikrochim Acta ; 191(3): 171, 2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38430344

RESUMO

This paper focuses on 3D printing using digital light processing (DLP) to create microchannel devices with inner diameters of 100, 200, and 500 µm and cater flow-through applications within the realm of analytical chemistry, in particular high-pressure liquid chromatographic separations. Effects of layer thickness and exposure time on channel dimensions and surface roughness were systematically investigated. Utilizing a commercially accessible 3D printer and acrylate resin formulation, we fabricated 100-500 µm i.d. squared and circular channel designs minimizing average surface roughness (< 20%) by applying a 20-µm layer thickness and exposure times ranging from 1.1 to 0.7 s. Pressure resistance was measured by encasing microdevices in an aluminum chip holder that integrated flat-bottom polyetheretherketon (PEEK) nanoports allowing to establish the micro-to-macro interface to the HPLC instrument. After thermal post-curing and finetuning the clamping force of the chip holder, a maximum pressure resistance of 650 bar (1.5% RSD) was reached (n = 3). A polymer monolithic support structure was successfully synthesized in situ with the confines of a 500 µm i.d. 3D printed microchannel. A proof-of-concept of a reversed-phase chromatographic gradient separation of intact proteins is demonstrated using an aqueous-organic mobile-phase with isopropanol as organic modifier.

4.
Br Dent J ; 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38326460

RESUMO

Introduction This study aims to assess if the COVID-19 pandemic impacted upon oral cancer staging in a single centre in the UK.Materials and methods Data were collected from the head and neck cancer database of a teaching hospital in London. Oral cancer diagnosis and staging in the peak period of the pandemic (March 2020-2021) were assessed against the one-year period (March 2019-2020) before the pandemic.Results In total, 25 cases of oral cancer were diagnosed in the pre-COVID-19 group compared to 26 in the COVID-19 cohort. Referrals from dentists accounted for 30% of cases of confirmed oral cancer in the COVID-19 class in comparison to 48% the year prior. Higher rates of overall TNM (tumour, lymph node, metastasis) staging at level 4a and above were observed in the COVID-19 cohort at 68% in comparison to 48% the year before.Conclusion Marginal non-statistically significant differences were noted of worsening stages of oral cancer presentations in the first year of the COVID-19 pandemic in this unit. Long-term studies on the outcomes of those diagnosed with oral cancer during the pandemic at a regional and national level will facilitate greater analysis on the impact the pandemic had on this cohort.

5.
Curr Opin Virol ; 67: 101412, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38838550

RESUMO

Mucosal-associated invariant T (MAIT) cells are an unconventional T cell population that are highly abundant in humans. They possess a semi-invariant T cell receptor (TCR) that recognises microbial metabolites formed during riboflavin biosynthesis, presented on a nonpolymorphic MHC-like molecule MR1. MAIT cells possess an array of effector functions, including type 1, type 17, and tissue repair activity. Deployment of these functions depends on the stimuli they receive through their TCR and/or cytokine receptors. Strong cytokine signalling, such as in response to vaccination, can bypass TCR triggering and provokes a strong proinflammatory response. Although data are still emerging, multiple aspects of MAIT cell biology are associated with modulation of immunity induced by the coronavirus disease 2019 mRNA and adenovirus vector vaccines. In this review, we will address how MAIT cells may play a role in immunogenicity of vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and how these cells can be harnessed as cellular adjuvants.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Células T Invariantes Associadas à Mucosa , SARS-CoV-2 , Humanos , Células T Invariantes Associadas à Mucosa/imunologia , Vacinas contra COVID-19/imunologia , COVID-19/imunologia , COVID-19/prevenção & controle , COVID-19/virologia , SARS-CoV-2/imunologia , Imunogenicidade da Vacina , Animais , Receptores de Antígenos de Linfócitos T/imunologia , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/metabolismo , Citocinas/imunologia , Citocinas/metabolismo
6.
Expert Opin Ther Pat ; 34(9): 733-757, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38958471

RESUMO

INTRODUCTION: COX-2 is a crucial enzyme in the manufacture of prostaglandins. The enzyme's metabolites might have an important function as regulators of the inflammatory response and other medical conditions such as cancer. Selective COX-2 inhibitors are believed to enhance or reverse the response of cancer chemotherapeutics. AREAS COVERED: This study addresses the chemical structures as well as the antitumor activity of new COX-2 inhibitors produced in the recent five years, aiming to provide an insight into the mechanism of COX-2 induced PGE2 powerful signal in cancer development. EXPERT OPINION: The significance of selective COX-2 inhibitors as an efficient superfamily of compounds with anti-inflammatory, anti-Alzheimer's, anti-Parkinson's disease, and anticancer properties has piqued the passion of academics in the field of drug development. Long-term usage of selective COX-2 inhibitors, such as celecoxib has been proven in clinical trials to lower the incidence of several human malignancies. Furthermore, celecoxib has the potential to greatly increase the effectiveness of chemotherapy. Our extensive understanding of selective COX-2 inhibitor SAR may aid in the development of safer and more effective selective COX-2 inhibitors as cancer chemopreventive agents. This review focuses on the different structural classes of selective COX-2 inhibitors, with a particular emphasis on their SAR.


Assuntos
Antineoplásicos , Inibidores de Ciclo-Oxigenase 2 , Ciclo-Oxigenase 2 , Desenvolvimento de Medicamentos , Neoplasias , Patentes como Assunto , Humanos , Inibidores de Ciclo-Oxigenase 2/farmacologia , Antineoplásicos/farmacologia , Neoplasias/tratamento farmacológico , Neoplasias/enzimologia , Animais , Ciclo-Oxigenase 2/metabolismo , Ciclo-Oxigenase 2/efeitos dos fármacos , Relação Estrutura-Atividade , Dinoprostona/metabolismo , Desenho de Fármacos
7.
bioRxiv ; 2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38106155

RESUMO

In this study we report a naturally evolved temperature-sensing electrical regulator in the cytochrome c oxidase of the Devil Worm, Halicephalobus mephisto. This extremophile metazoan was isolated 1.3 km underground in a South African goldmine, where it adapted to heat and potentially to hypoxia, making its mitochondrial sequence a likely target of adaptational change. We obtained the full mitochondrial genome sequence of this organism, and show through dN/dS analysis statistically robust evidence of positive selection in H. mephisto cytochrome c oxidase subunits. Seventeen of these positively-selected amino acid substitutions were localized in proximity to the H- and K-pathway proton channels of the complex. Surprisingly, the H. mephisto cytochrome c oxidase proton pump completely shuts down at low temperatures (20°C) leading to approximately a 4.8-fold reduction in the transmembrane proton gradient voltage (ΔΨm) compared to optimal temperature (37°C). Direct measurement of oxygen consumption found a corresponding 4.7-fold drop at 20°C compared to 37°C. Correspondingly, the lifecycle of H. mephisto takes four-fold longer at the low temperature compared to higher. This elegant evolutionary adaptation creates a finely-tuned mitochondrial temperature sensor, allowing this ectothermic organism to maximize its reproductive success in varying environmental temperatures. Our study shows that evolutionary innovation may remodel core metabolism to make it more accurately map onto environmental variation.

8.
Artigo em Inglês | Arca: Repositório institucional da Fiocruz | ID: arc-52426

RESUMO

A Variante de Preocupação Ômicron (B.1.1.529) trouxe uma grande expansão mundial dos contágios pelo SARS-CoV-2, mesmo em países onde a imunização contra o vírus já estava avançada. Para compreender como a coleção de mutações da Glicoproteína S da Ômicron leva ao escape da resposta imunológica, um esforço internacional de pesquisa que incluiu cientistas da Rede Genômica Fiocruz analisou as estruturas de proteínas, além da neutralização da capacidade de causar infecção ao expôr amostras da Ômicron a diferentes preparados contendo anticorpos como: 1) o soro de pacientes infectados com outras amostras do vírus, 2) os chamados "anticorpos monoclonais" selecionados em laboratório, e 3) o soro de pessoas vacinadas.O presente artigo, fruto desta colaboração para o estudo de múltiplos fatores envolvidos no escape da resposta imune apresentado pela Ômicron, demonstrou que a nova variante é quase 17 vezes mais resistente à neutralização pelos anticorpos gerados em resposta a uma linhagem da primeira onda da pandemia. O estudo mostra ainda que um esquema vacinal de três doses aumenta consideravelmente a resposta ao vírus, incluindo a neutralização da variante Ômicron, que não era suficiente apenas com duas doses do imunizante. O artigo mostra ainda que a estrutura de porções da Glicoproteína S da Ômicron estão envolvidas em "compensar" a ação de anticorpos através de uma ligação mais forte à ACE2, molécula que atua como receptor viral nas células humanas.


Assuntos
Infecções por Coronavirus , COVID-19
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