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1.
Sci Rep ; 14(1): 8487, 2024 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-38605059

RESUMO

Breast cancer has rapidly increased in prevalence in recent years, making it one of the leading causes of mortality worldwide. Among all cancers, it is by far the most common. Diagnosing this illness manually requires significant time and expertise. Since detecting breast cancer is a time-consuming process, preventing its further spread can be aided by creating machine-based forecasts. Machine learning and Explainable AI are crucial in classification as they not only provide accurate predictions but also offer insights into how the model arrives at its decisions, aiding in the understanding and trustworthiness of the classification results. In this study, we evaluate and compare the classification accuracy, precision, recall, and F1 scores of five different machine learning methods using a primary dataset (500 patients from Dhaka Medical College Hospital). Five different supervised machine learning techniques, including decision tree, random forest, logistic regression, naive bayes, and XGBoost, have been used to achieve optimal results on our dataset. Additionally, this study applied SHAP analysis to the XGBoost model to interpret the model's predictions and understand the impact of each feature on the model's output. We compared the accuracy with which several algorithms classified the data, as well as contrasted with other literature in this field. After final evaluation, this study found that XGBoost achieved the best model accuracy, which is 97%.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/diagnóstico , Teorema de Bayes , Bangladesh/epidemiologia , Mama , Aprendizado de Máquina , Hidrolases
2.
Hepatol Commun ; 8(5)2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38668730

RESUMO

BACKGROUND: We previously demonstrated the successful use of in vivo CRISPR gene editing to delete 4-hydroxyphenylpyruvate dioxygenase (HPD) to rescue mice deficient in fumarylacetoacetate hydrolase (FAH), a disorder known as hereditary tyrosinemia type 1 (HT1). The aim of this study was to develop an ex vivo gene-editing protocol and apply it as a cell therapy for HT1. METHODS: We isolated hepatocytes from wild-type (C57BL/6J) and Fah-/- mice and then used an optimized electroporation protocol to deliver Hpd-targeting CRISPR-Cas9 ribonucleoproteins into hepatocytes. Next, hepatocytes were transiently incubated in cytokine recovery media formulated to block apoptosis, followed by splenic injection into recipient Fah-/- mice. RESULTS: We observed robust engraftment and expansion of transplanted gene-edited hepatocytes from wild-type donors in the livers of recipient mice when transient incubation with our cytokine recovery media was used after electroporation and negligible engraftment without the media (mean: 46.8% and 0.83%, respectively; p=0.0025). Thus, the cytokine recovery medium was critical to our electroporation protocol. When hepatocytes from Fah-/- mice were used as donors for transplantation, we observed 35% and 28% engraftment for Hpd-Cas9 ribonucleoproteins and Cas9 mRNA, respectively. Tyrosine, phenylalanine, and biochemical markers of liver injury normalized in both Hpd-targeting Cas9 ribonucleoprotein and mRNA groups independent of induced inhibition of Hpd through nitisinone, indicating correction of disease indicators in Fah-/- mice. CONCLUSIONS: The successful liver cell therapy for HT1 validates our protocol and, despite the known growth advantage of HT1, showcases ex vivo gene editing using electroporation in combination with liver cell therapy to cure a disease model. These advancements underscore the potential impacts of electroporation combined with transplantation as a cell therapy.


Assuntos
Edição de Genes , Hepatócitos , Hidrolases , Camundongos Endogâmicos C57BL , Tirosinemias , Animais , Tirosinemias/terapia , Tirosinemias/genética , Edição de Genes/métodos , Camundongos , Hepatócitos/transplante , Hepatócitos/metabolismo , Hidrolases/genética , Terapia Baseada em Transplante de Células e Tecidos/métodos , Sistemas CRISPR-Cas , Eletroporação/métodos , Camundongos Knockout , 4-Hidroxifenilpiruvato Dioxigenase/genética , Modelos Animais de Doenças , Cicloexanonas , Nitrobenzoatos
3.
ACS Appl Mater Interfaces ; 16(15): 18490-18502, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38573937

RESUMO

Evading recognition of immune cells is a well-known strategy of tumors used for their survival. One of the immune evasion mechanisms is the synthesis of kynurenine (KYN), a metabolite of tryptophan, which suppresses the effector T cells. Therefore, lowering the KYN concentration can be an efficient antitumor therapy by restoring the activity of immune cells. Recently, kynureninase (KYNase), which is an enzyme transforming KYN into anthranilate, was demonstrated to show the potential to decrease KYN concentration and inhibit tumor growth. However, due to the limited bioavailability and instability of proteins in vivo, it has been challenging to maintain the KYNase concentration sufficiently high in the tumor microenvironment (TME). Here, we developed a nanoparticle system loaded with KYNase, which formed a Biodegradable and Implantable Nanoparticle Depot named 'BIND' following subcutaneous injection. The BIND sustainably supplied KYNase around the TME while located around the tumor, until it eventually degraded and disappeared. As a result, the BIND system enhanced the proliferation and cytokine production of effector T cells in the TME, followed by tumor growth inhibition and increased mean survival. Finally, we showed that the BIND carrying KYNase significantly synergized with PD-1 blockade in three mouse models of colon cancer, breast cancer, and melanoma.


Assuntos
Hidrolases , Cinurenina , Melanoma , Camundongos , Animais , Cinurenina/metabolismo , Evasão Tumoral , Imunoterapia , Microambiente Tumoral
4.
Int J Mol Sci ; 25(8)2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38673749

RESUMO

The anticancer potential of Levilactobacillus brevis KU15176 against the stomach cancer cell line AGS has been reported previously. In this study, we aimed to analyze the genome of L. brevis KU15176 and identify key genes that may have potential anticancer properties. Among potential anticancer molecules, the role of arginine deiminase (ADI) in conferring an antiproliferative functionality was confirmed. In vitro assay against AGS cell line confirmed that recombinant ADI from L. brevis KU15176 (ADI_br, 5 µg/mL), overexpressed in E. coli BL21 (DE3), exerted an inhibitory effect on AGS cell growth, resulting in a 65.32% reduction in cell viability. Moreover, the expression of apoptosis-related genes, such as bax, bad, caspase-7, and caspase-3, as well as the activity of caspase-9 in ADI_br-treated AGS cells, was higher than those in untreated (culture medium-only) cells. The cell-scattering behavior of ADI_br-treated cells showed characteristics of apoptosis. Flow cytometry analyses of AGS cells treated with ADI_br for 24 and 28 h revealed apoptotic rates of 11.87 and 24.09, respectively, indicating the progression of apoptosis in AGS cells after ADI_br treatment. This study highlights the potential of ADI_br as an effective enzyme for anticancer applications.


Assuntos
Apoptose , Proliferação de Células , Hidrolases , Levilactobacillus brevis , Proteínas Recombinantes , Neoplasias Gástricas , Humanos , Apoptose/efeitos dos fármacos , Hidrolases/metabolismo , Hidrolases/genética , Hidrolases/farmacologia , Linhagem Celular Tumoral , Neoplasias Gástricas/patologia , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/genética , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/farmacologia , Proteínas Recombinantes/genética , Proliferação de Células/efeitos dos fármacos , Levilactobacillus brevis/genética , Levilactobacillus brevis/enzimologia , Antineoplásicos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
5.
Sci Rep ; 14(1): 9231, 2024 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-38649439

RESUMO

This study investigated the impact of overexpressing the mitochondrial enzyme Fumarylacetoacetate hydrolase domain-containing protein 1 (FAHD1) in human osteosarcoma epithelial cells (U2OS) in vitro. While the downregulation or knockdown of FAHD1 has been extensively researched in various cell types, this study aimed to pioneer the exploration of how increased catalytic activity of human FAHD1 isoform 1 (hFAHD1.1) affects human cell metabolism. Our hypothesis posited that elevation in FAHD1 activity would lead to depletion of mitochondrial oxaloacetate levels. This depletion could potentially result in a decrease in the flux of the tricarboxylic acid (TCA) cycle, thereby accompanied by reduced ROS production. In addition to hFAHD1.1 overexpression, stable U2OS cell lines were established overexpressing a catalytically enhanced variant (T192S) and a loss-of-function variant (K123A) of hFAHD1. It is noteworthy that homologs of the T192S variant are present in animals exhibiting increased resistance to oxidative stress and cancer. Our findings demonstrate that heightened activity of the mitochondrial enzyme FAHD1 decreases cellular ROS levels in U2OS cells. However, these results also prompt a series of intriguing questions regarding the potential role of FAHD1 in mitochondrial metabolism and cellular development.


Assuntos
Neoplasias Ósseas , Hidrolases , Mitocôndrias , Osteossarcoma , Espécies Reativas de Oxigênio , Humanos , Neoplasias Ósseas/metabolismo , Neoplasias Ósseas/genética , Neoplasias Ósseas/patologia , Linhagem Celular Tumoral , Ciclo do Ácido Cítrico , Mitocôndrias/metabolismo , Osteossarcoma/metabolismo , Osteossarcoma/genética , Osteossarcoma/patologia , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Hidrolases/genética , Hidrolases/metabolismo
6.
Cell Rep ; 43(3): 113942, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38489266

RESUMO

Tumor-associated macrophages (TAMs) shape tumor immunity and therapeutic efficacy. However, it is poorly understood whether and how post-translational modifications (PTMs) intrinsically affect the phenotype and function of TAMs. Here, we reveal that peptidylarginine deiminase 4 (PAD4) exhibits the highest expression among common PTM enzymes in TAMs and negatively correlates with the clinical response to immune checkpoint blockade. Genetic and pharmacological inhibition of PAD4 in macrophages prevents tumor progression in tumor-bearing mouse models, accompanied by an increase in macrophage major histocompatibility complex (MHC) class II expression and T cell effector function. Mechanistically, PAD4 citrullinates STAT1 at arginine 121, thereby promoting the interaction between STAT1 and protein inhibitor of activated STAT1 (PIAS1), and the loss of PAD4 abolishes this interaction, ablating the inhibitory role of PIAS1 in the expression of MHC class II machinery in macrophages and enhancing T cell activation. Thus, the PAD4-STAT1-PIAS1 axis is an immune restriction mechanism in macrophages and may serve as a cancer immunotherapy target.


Assuntos
Hidrolases , Processamento de Proteína Pós-Traducional , Camundongos , Animais , Desiminases de Arginina em Proteínas/metabolismo , Proteína-Arginina Desiminase do Tipo 4/genética , Proteína-Arginina Desiminase do Tipo 4/metabolismo , Hidrolases/metabolismo , Antígenos de Histocompatibilidade Classe II/metabolismo , Macrófagos/metabolismo
7.
Microb Cell Fact ; 23(1): 82, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38481270

RESUMO

BACKGROUND: Colorectal cancer (CRC) is one of the most commonly diagnosed cancers, posing a serious public health challenge that necessitates the development of new therapeutics, therapies, and prevention methods. Among the various therapeutic approaches, interventions involving lactic acid bacteria (LAB) as probiotics and postbiotics have emerged as promising candidates for treating and preventing CRC. While human-isolated LAB strains are considered highly favorable, those sourced from environmental reservoirs such as dairy and fermented foods are also being recognized as potential sources for future therapeutics. RESULTS: In this study, we present a novel and therapeutically promising strain, Lactococcus lactis ssp. lactis Lc4, isolated from dairy sources. Lc4 demonstrated the ability to release the cytostatic agent - arginine deiminase (ADI) - into the post-cultivation supernatant when cultured under conditions mimicking the human gut environment. Released arginine deiminase was able to significantly reduce the growth of HT-29 and HCT116 cells due to the depletion of arginine, which led to decreased levels of c-Myc, reduced phosphorylation of p70-S6 kinase, and cell cycle arrest. The ADI release and cytostatic properties were strain-dependent, as was evident from comparison to other L. lactis ssp. lactis strains. CONCLUSION: For the first time, we unveil the anti-proliferative properties of the L. lactis cell-free supernatant (CFS), which are independent of bacteriocins or other small molecules. We demonstrate that ADI, derived from a dairy-Generally Recognized As Safe (GRAS) strain of L. lactis, exhibits anti-proliferative activity on cell lines with different levels of argininosuccinate synthetase 1 (ASS1) expression. A unique feature of the Lc4 strain is also its capability to release ADI into the extracellular space. Taken together, we showcase L. lactis ADI and the Lc4 strain as promising, potential therapeutic agents with broad applicability.


Assuntos
Citostáticos , Lactococcus lactis , Humanos , Citostáticos/metabolismo , Lactococcus lactis/metabolismo , Hidrolases/metabolismo , Linhagem Celular Tumoral , Arginina
8.
Molecules ; 29(6)2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38542939

RESUMO

The emergence of multidrug-resistant and extensively drug-resistant Mycobacterium tuberculosis (M. tuberculosis) has become a major medical problem. S-adenosyl-L-homocysteine hydrolase (MtSAHH) was selected as the target protein for the identification of novel anti-TB drugs. Dual hierarchical in silico Structure-Based Drug Screening was performed using a 3D compound structure library (with over 150 thousand synthetic chemicals) to identify compounds that bind to MtSAHH's active site. In vitro experiments were conducted to verify whether the nine compounds selected as new drug candidates exhibited growth-inhibitory effects against mycobacteria. Eight of the nine compounds that were predicted by dual hierarchical screening showed growth-inhibitory effects against Mycobacterium smegmatis (M. smegmatis), a model organism for M. tuberculosis. Compound 7 showed the strongest antibacterial activity, with an IC50 value of 30.2 µM. Compound 7 did not inhibit the growth of Gram-negative bacteria or exert toxic effects on human cells. Molecular dynamics simulations of 40 ns using the MtSAHH-Compound 7 complex structure suggested that Compound 7 interacts stably with the MtSAHH active site. These in silico and in vitro results suggested that Compound 7 is a promising lead compound for the development of new anti-TB drugs.


Assuntos
Mycobacterium tuberculosis , Tuberculose , Humanos , Antituberculosos/química , Avaliação Pré-Clínica de Medicamentos , Tuberculose/microbiologia , Homocisteína/farmacologia , Hidrolases/farmacologia , Simulação de Acoplamento Molecular
9.
Int J Mol Sci ; 25(6)2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38542155

RESUMO

Peptidylarginine deiminases (PADs or PADIs) catalyze the conversion of positively charged arginine to neutral citrulline, which alters target protein structure and function. Our previous work established that gonadotropin-releasing hormone agonist (GnRHa) stimulates PAD2-catalyzed histone citrullination to epigenetically regulate gonadotropin gene expression in the gonadotrope-derived LßT2 cell line. However, PADs are also found in the cytoplasm. Given this, we used mass spectrometry (MS) to identify additional non-histone proteins that are citrullinated following GnRHa stimulation and characterized the temporal dynamics of this modification. Our results show that actin and tubulin are citrullinated, which led us to hypothesize that GnRHa might induce their citrullination to modulate cytoskeletal dynamics and architecture. The data show that 10 nM GnRHa induces the citrullination of ß-actin, with elevated levels occurring at 10 min. The level of ß-actin citrullination is reduced in the presence of the pan-PAD inhibitor biphenyl-benzimidazole-Cl-amidine (BB-ClA), which also prevents GnRHa-induced actin reorganization in dispersed murine gonadotrope cells. GnRHa induces the citrullination of ß-tubulin, with elevated levels occurring at 30 min, and this response is attenuated in the presence of PAD inhibition. To examine the functional consequence of ß-tubulin citrullination, we utilized fluorescently tagged end binding protein 1 (EB1-GFP) to track the growing plus end of microtubules (MT) in real time in transfected LßT2 cells. Time-lapse confocal microscopy of EB1-GFP reveals that the MT average lifetime increases following 30 min of GnRHa treatment, but this increase is attenuated by PAD inhibition. Taken together, our data suggest that GnRHa-induced citrullination alters actin reorganization and MT lifetime in gonadotrope cells.


Assuntos
Actinas , Citrulinação , Camundongos , Animais , Actinas/metabolismo , Tubulina (Proteína)/metabolismo , Citoesqueleto/metabolismo , Microtúbulos/metabolismo , Citrulina/metabolismo , Hormônio Liberador de Gonadotropina/metabolismo , Hidrolases/metabolismo
10.
J Agric Food Chem ; 72(13): 7279-7290, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38519413

RESUMO

PepXLcMY-3, an X-prolyl dipeptidyl aminopeptidase derived from Lactobacillus lactis MY-3, was screened and recombinantly expressed in Escherichia coli. The enzyme could exhibit about 40% activity within the pH range of 6.0-10. To further improve the pH robustness, site E396 located in the active pocket was discovered through alanine scanning. The mutant E396I displayed both developed activity and kcat/Km. The optimal pH of E396I shifted from 6.0 to 10 compared to WT, with the relative activity within the pH range of 6.0-10 significantly increased. The site K648 was then proposed by semirational design. The activity of mutant E396I/K648D reached 4.03 U/mg. The optimal pH was restored to 6.0, and the pH stability was further improved. E396I/K648D could totally hydrolyze ß-casomorphin 7 within 30 min. The hydrolysate showed 64.5% inhibition on angiotensin I converting enzyme, which was more efficient than those produced by E396I and WT, 23.2 and 44.7%, respectively.


Assuntos
Lactococcus lactis , Lactococcus lactis/genética , Lactococcus lactis/metabolismo , Sequência de Aminoácidos , Dipeptidil Peptidases e Tripeptidil Peptidases , Peptídeos/genética , Hidrolases , Aminopeptidases/genética , Aminopeptidases/química , Aminopeptidases/metabolismo , Concentração de Íons de Hidrogênio
11.
Elife ; 122024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38488661

RESUMO

R-loops are non-canonical DNA structures that form during transcription and play diverse roles in various physiological processes. Disruption of R-loop homeostasis can lead to genomic instability and replication impairment, contributing to several human diseases, including cancer. Although the molecular mechanisms that protect cells against such events are not fully understood, recent research has identified fork protection factors and DNA damage response proteins as regulators of R-loop dynamics. In this study, we identify the Werner helicase-interacting protein 1 (WRNIP1) as a novel factor that counteracts transcription-associated DNA damage upon replication perturbation. Loss of WRNIP1 leads to R-loop accumulation, resulting in collisions between the replisome and transcription machinery. We observe co-localization of WRNIP1 with transcription/replication complexes and R-loops after replication perturbation, suggesting its involvement in resolving transcription-replication conflicts. Moreover, WRNIP1-deficient cells show impaired replication restart from transcription-induced fork stalling. Notably, transcription inhibition and RNase H1 overexpression rescue all the defects caused by loss of WRNIP1. Importantly, our findings highlight the critical role of WRNIP1 ubiquitin-binding zinc finger (UBZ) domain in preventing pathological persistence of R-loops and limiting DNA damage, thereby safeguarding genome integrity.


Assuntos
ATPases Associadas a Diversas Atividades Celulares , Replicação do DNA , Proteínas de Ligação a DNA , Humanos , ATPases Associadas a Diversas Atividades Celulares/metabolismo , DNA , Dano ao DNA , Proteínas de Ligação a DNA/metabolismo , Instabilidade Genômica , Hidrolases/genética , Dedos de Zinco
12.
Med Microbiol Immunol ; 213(1): 3, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38448747

RESUMO

Multidrug-resistant clinical isolates of Moraxella catarrhalis have emerged, increasing the demand for the identification of new treatment and prevention strategies. A thorough understanding of how M. catarrhalis can establish an infection and respond to different stressors encountered in the host is crucial for new drug-target identification. Formaldehyde is a highly cytotoxic compound that can be produced endogenously as a by-product of metabolism and exogenously from environmental sources. Pathways responsible for formaldehyde detoxification are thus essential and are found in all domains of life. The current work investigated the role of the system consisting of the S-hydroxymethyl alcohol dehydrogenase (AdhC), a Zn-dependent class III alcohol dehydrogenase, and the S-formyl glutathione hydrolase (FghA) in the formaldehyde detoxification process in M. catarrhalis. Bioinformatics showed that the components of the system are conserved across the species and are highly similar to those of Streptococcus pneumoniae, which share the same biological niche. Isogenic mutants were constructed to study the function of the system in M. catarrhalis. A single fghA knockout mutant did not confer sensitivity to formaldehyde, while the adhC-fghA double mutant is formaldehyde-sensitive. In addition, both mutants were significantly cleared in a murine pulmonary model of infection as compared to the wild type, demonstrating the system's importance for this pathogen's virulence. The respective phenotypes were reversed upon the genetic complementation of the mutants. To date, this is the first study investigating the role of the AdhC-FghA system in formaldehyde detoxification and pathogenesis of M. catarrhalis.


Assuntos
Moraxella catarrhalis , Streptococcus pneumoniae , Animais , Camundongos , Moraxella catarrhalis/genética , Streptococcus pneumoniae/genética , Formaldeído , Glutationa , Hidrolases
13.
Sci Adv ; 10(13): eadk7201, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38536910

RESUMO

Enzymes populate ensembles of structures necessary for catalysis that are difficult to experimentally characterize. We use time-resolved mix-and-inject serial crystallography at an x-ray free electron laser to observe catalysis in a designed mutant isocyanide hydratase (ICH) enzyme that enhances sampling of important minor conformations. The active site exists in a mixture of conformations, and formation of the thioimidate intermediate selects for catalytically competent substates. The influence of cysteine ionization on the ICH ensemble is validated by determining structures of the enzyme at multiple pH values. Large molecular dynamics simulations in crystallo and time-resolved electron density maps show that Asp17 ionizes during catalysis and causes conformational changes that propagate across the dimer, permitting water to enter the active site for intermediate hydrolysis. ICH exhibits a tight coupling between ionization of active site residues and catalysis-activated protein motions, exemplifying a mechanism of electrostatic control of enzyme dynamics.


Assuntos
Simulação de Dinâmica Molecular , Proteínas , Cristalografia por Raios X , Proteínas/química , Catálise , Conformação Proteica , Hidrolases
14.
Nat Commun ; 15(1): 2452, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38503748

RESUMO

ADP-ribosylation is a reversible post-translational modification involved in various cellular activities. Removal of ADP-ribosylation requires (ADP-ribosyl)hydrolases, with macrodomain enzymes being a major family in this category. The pathogen Legionella pneumophila mediates atypical ubiquitination of host targets using the SidE effector family in a process that involves ubiquitin ADP-ribosylation on arginine 42 as an obligatory step. Here, we show that the Legionella macrodomain effector MavL regulates this pathway by reversing the arginine ADP-ribosylation, likely to minimize potential detrimental effects caused by the modified ubiquitin. We determine the crystal structure of ADP-ribose-bound MavL, providing structural insights into recognition of the ADP-ribosyl group and catalytic mechanism of its removal. Further analyses reveal DUF4804 as a class of MavL-like macrodomain enzymes whose representative members show unique selectivity for mono-ADP-ribosylated arginine residue in synthetic substrates. We find such enzymes are also present in eukaryotes, as exemplified by two previously uncharacterized (ADP-ribosyl)hydrolases in Drosophila melanogaster. Crystal structures of several proteins in this class provide insights into arginine specificity and a shared mode of ADP-ribose interaction distinct from previously characterized macrodomains. Collectively, our study reveals a new regulatory layer of SidE-catalyzed ubiquitination and expands the current understanding of macrodomain enzymes.


Assuntos
Legionella , Ubiquitina , Animais , Ubiquitina/metabolismo , Legionella/metabolismo , Drosophila melanogaster/metabolismo , ADP-Ribosilação , Adenosina Difosfato Ribose/metabolismo , Hidrolases/metabolismo
15.
Methods Mol Biol ; 2755: 201-212, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38319580

RESUMO

The hypoxic microenvironment in solid tumors affects the metabolism of tumor cells and infiltrating immune cells, which aids in robust tumor growth and expansion. Myeloid-derived suppressor cells (MDSCs) are heterogenous immature myeloid cells in the TME, which play an essential role in immune evasion by subverting T/NK cell-mediated killing. The immunosuppressive function of MDSCs is tightly regulated to the metabolic pathways, in which hypoxia plays a critical role. In this chapter, we describe the isolation of murine MDSCs from bone marrows and the measurement of the transcriptomic changes of essential metabolic enzymes under hypoxic conditions. This method can be applied to study MDSCs function, mimicking the hypoxic environment in vitro. This method can be utilized to investigate the critical metabolic alterations under a given tumor context and help evaluate the efficacy of metabolic-targeted therapies in the long run.


Assuntos
Perfilação da Expressão Gênica , Células Mieloides , Animais , Camundongos , Hidrolases , Hipóxia , Evasão da Resposta Imune
16.
J Biol Chem ; 300(3): 105783, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38395309

RESUMO

Poly(ethylene terephthalate) (PET) is a major plastic polymer utilized in the single-use and textile industries. The discovery of PET-degrading enzymes (PETases) has led to an increased interest in the biological recycling of PET in addition to mechanical recycling. IsPETase from Ideonella sakaiensis is a candidate catalyst, but little is understood about its structure-function relationships with regards to PET degradation. To understand the effects of mutations on IsPETase productivity, we develop a directed evolution assay to identify mutations beneficial to PET film degradation at 30 °C. IsPETase also displays enzyme concentration-dependent inhibition effects, and surface crowding has been proposed as a causal phenomenon. Based on total internal reflectance fluorescence microscopy and adsorption experiments, IsPETase is likely experiencing crowded conditions on PET films. Molecular dynamics simulations of IsPETase variants reveal a decrease in active site flexibility in free enzymes and reduced probability of productive active site formation in substrate-bound enzymes under crowding. Hence, we develop a surface crowding model to analyze the biochemical effects of three hit mutations (T116P, S238N, S290P) that enhanced ambient temperature activity and/or thermostability. We find that T116P decreases susceptibility to crowding, resulting in higher PET degradation product accumulation despite no change in intrinsic catalytic rate. In conclusion, we show that a macromolecular crowding-based biochemical model can be used to analyze the effects of mutations on properties of PETases and that crowding behavior is a major property to be targeted for enzyme engineering for improved PET degradation.


Assuntos
Burkholderiales , Hidrolases , Polietilenotereftalatos , Hidrolases/química , Hidrolases/genética , Hidrolases/metabolismo , Polietilenotereftalatos/química , Polietilenotereftalatos/metabolismo , Reciclagem , Cinética , Burkholderiales/enzimologia , Modelos Químicos
17.
JAMA Oncol ; 10(4): 475-483, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38358753

RESUMO

Importance: Arginine deprivation using ADI-PEG20 (pegargiminase) combined with chemotherapy is untested in a randomized study among patients with cancer. ATOMIC-Meso (ADI-PEG20 Targeting of Malignancies Induces Cytotoxicity-Mesothelioma) is a pivotal trial comparing standard first-line chemotherapy plus pegargiminase or placebo in patients with nonepithelioid pleural mesothelioma. Objective: To determine the effect of pegargiminase-based chemotherapy on survival in nonepithelioid pleural mesothelioma, an arginine-auxotrophic tumor. Design, Setting, and Participants: This was a phase 2-3, double-blind randomized clinical trial conducted at 43 centers in 5 countries that included patients with chemotherapy-naive nonepithelioid pleural mesothelioma from August 1, 2017, to August 15, 2021, with at least 12 months' follow-up. Final follow-up was on August 15, 2022. Data analysis was performed from March 2018 to June 2023. Intervention: Patients were randomly assigned (1:1) to receive weekly intramuscular pegargiminase (36.8 mg/m2) or placebo. All patients received intravenous pemetrexed (500 mg/m2) and platinum (75-mg/m2 cisplatin or carboplatin area under the curve 5) chemotherapy every 3 weeks up to 6 cycles. Pegargiminase or placebo was continued until progression, toxicity, or 24 months. Main Outcomes and Measures: The primary end point was overall survival, and secondary end points were progression-free survival and safety. Response rate by blinded independent central review was assessed in the phase 2 portion only. Results: Among 249 randomized patients (mean [SD] age, 69.5 [7.9] years; 43 female individuals [17.3%] and 206 male individuals [82.7%]), all were included in the analysis. The median overall survival was 9.3 months (95% CI, 7.9-11.8 months) with pegargiminase-chemotherapy as compared with 7.7 months (95% CI, 6.1-9.5 months) with placebo-chemotherapy (hazard ratio [HR] for death, 0.71; 95% CI, 0.55-0.93; P = .02). The median progression-free survival was 6.2 months (95% CI, 5.8-7.4 months) with pegargiminase-chemotherapy as compared with 5.6 months (95% CI, 4.1-5.9 months) with placebo-chemotherapy (HR, 0.65; 95% CI, 0.46-0.90; P = .02). Grade 3 to 4 adverse events with pegargiminase occurred in 36 patients (28.8%) and with placebo in 21 patients (16.9%); drug hypersensitivity and skin reactions occurred in the experimental arm in 3 patients (2.4%) and 2 patients (1.6%), respectively, and none in the placebo arm. Rates of poststudy treatments were comparable in both arms (57 patients [45.6%] with pegargiminase vs 58 patients [46.8%] with placebo). Conclusions and Relevance: In this randomized clinical trial of arginine depletion with pegargiminase plus chemotherapy, survival was extended beyond standard chemotherapy with a favorable safety profile in patients with nonepithelioid pleural mesothelioma. Pegargiminase-based chemotherapy as a novel antimetabolite strategy for mesothelioma validates wider clinical testing in oncology. Trial Registration: ClinicalTrials.gov Identifier: NCT02709512.


Assuntos
Hidrolases , Neoplasias Pulmonares , Mesotelioma Maligno , Mesotelioma , Neoplasias Pleurais , Polietilenoglicóis , Idoso , Feminino , Humanos , Masculino , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Arginina/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Mesotelioma/tratamento farmacológico , Mesotelioma Maligno/tratamento farmacológico , Mesotelioma Maligno/etiologia , Neoplasias Pleurais/tratamento farmacológico
18.
Mol Carcinog ; 63(4): 647-662, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38197491

RESUMO

Colorectal cancer (CRC) continues to be a prevalent malignancy, posing a significant risk to human health. The involvement of alpha/beta hydrolase domain 6 (ABHD6), a serine hydrolase family member, in CRC development was suggested by our analysis of clinical data. However, the role of ABHD6 in CRC remains unclear. This study seeks to elucidate the clinical relevance, biological function, and potential molecular mechanisms of ABHD6 in CRC. We investigated the role of ABHD6 in clinical settings, conducting proliferation, migration, and cell cycle assays. To determine the influence of ABHD6 expression levels on Oxaliplatin sensitivity, we also performed apoptosis assays. RNA sequencing and KEGG analysis were utilized to uncover the potential molecular mechanisms of ABHD6. Furthermore, we validated its expression levels using Western blot and reactive oxygen species (ROS) detection assays. Our results demonstrated that ABHD6 expression in CRC tissues was notably lower compared to adjacent normal tissues. This low expression correlated with a poorer prognosis for CRC patients. Moreover, ABHD6 overexpression impeded CRC cell proliferation and migration while inducing G0/G1 cell cycle arrest. In vivo experiments revealed that downregulation of ABHD6 resulted in an increase in tumor weight and volume. Mechanistically, ABHD6 overexpression inhibited the activation of the AKT signaling pathway and decreased ROS levels in CRC cells, suggesting the role of ABHD6 in CRC progression via the AKT signaling pathway. Our findings demonstrate that ABHD6 functions as a tumor suppressor, primarily by inhibiting the AKT signaling pathway. This role establishes ABHD6 as a promising prognostic biomarker and a potential therapeutic target for CRC patients.


Assuntos
Neoplasias Colorretais , Proteínas Proto-Oncogênicas c-akt , Humanos , Espécies Reativas de Oxigênio , Proliferação de Células , Pontos de Checagem da Fase G1 do Ciclo Celular , Hidrolases , Transdução de Sinais , Neoplasias Colorretais/genética , Linhagem Celular Tumoral , Movimento Celular , Monoacilglicerol Lipases
19.
Sci Rep ; 14(1): 2324, 2024 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-38282060

RESUMO

Medical diagnosis through prediction and analysis is par excellence in integrating modern technologies such as the Internet of Things (IoT). With the aid of such technologies, clinical assessments are eased with protracted computing. Specifically, cancer research through structure prediction and analysis is improved through human and machine interventions sustaining precision improvements. This article, therefore, introduces a Protein Structure Prediction Technique based on Three-Dimensional Sequence. This sequence is modeled using amino acids and their folds observed during the pre-initial cancer stages. The observed sequences and the inflammatory response score of the structure are used to predict the impact of cancer. In this process, ensemble learning is used to identify sequence and folding responses to improve inflammations. This score is correlated with the clinical data for structures and their folds independently for determining the structure changes. Such changes through different sequences are handled using repeated ensemble learning for matching and unmatching response scores. The introduced idea integrated with deep ensemble learning and IoT combination, notably employing stacking method for enhanced cancer prediction precision and interdisciplinary collaboration. The proposed technique improves prediction precision, data correlation, and change detection by 11.83%, 8.48%, and 13.23%, respectively. This technique reduces correlation time and complexity by 10.43% and 12.33%, respectively.


Assuntos
Antifibrinolíticos , Internet das Coisas , Neoplasias , Humanos , Neoplasias/diagnóstico , Aminoácidos , Correlação de Dados , Hidrolases
20.
Mar Drugs ; 22(1)2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38248666

RESUMO

Mass spectrometry-based chemical proteomic approaches using limited proteolysis have become a powerful tool for the identification and analysis of the interactions between a small molecule (SM) and its protein target(s). Gracilioether A (GeA) is a polyketide isolated from a marine sponge, for which we aimed to trace the interactome using this strategy. DARTS (Drug Affinity Responsive Target Stability) and t-LiP-MS (targeted-Limited Proteolysis-Mass Spectrometry) represented the main techniques used in this study. DARTS was applied on HeLa cell lysate for the identification of the GeA target proteins, and t-LiP-MS was employed to investigate the protein's regions involved in the binding with GeA. The results were complemented through the use of binding studies using Surface Plasmon Resonance (SPR) and in silico molecular docking experiments. Ubiquitin carboxyl-terminal hydrolase 5 (USP5) was identified as a promising target of GeA, and the interaction profile of the USP5-GeA complex was explained. USP5 is an enzyme involved in the pathway of protein metabolism through the disassembly of the polyubiquitin chains on degraded proteins into ubiquitin monomers. This activity is connected to different cellular functions concerning the maintenance of chromatin structure and receptors and the degradation of abnormal proteins and cancerogenic progression. On this basis, this structural information opens the way to following studies focused on the definition of the biological potential of Gracilioether A and the rational development of novel USP5 inhibitors based on a new structural skeleton.


Assuntos
Compostos Heterocíclicos com 3 Anéis , Policetídeos , Proteômica , Humanos , Células HeLa , Simulação de Acoplamento Molecular , Hidrolases , Ubiquitinas
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