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1.
Int J Mol Sci ; 25(19)2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39408929

RESUMO

The landscape of clinical management for metastatic melanoma (MM) and other solid tumors has been modernized by the advent of immune checkpoint inhibitors (ICI), including programmed cell death-1 (PD-1), programmed cell death-ligand 1 (PD-L1), and cytotoxic T lymphocyte antigen 4 (CTLA-4) inhibitors. While these agents demonstrate efficacy in suppressing tumor growth, they also lead to immune-related adverse events (irAEs), resulting in the exacerbation of autoimmune diseases such as rheumatoid arthritis (RA), ulcerative colitis (UC), and Crohn's disease (CD). The immune checkpoint inhibitors offer promising advancements in the treatment of melanoma and other cancers, but they also present significant challenges related to irAEs and autoimmune diseases. Ongoing research is crucial to better understand these challenges and develop strategies for mitigating adverse effects while maximizing therapeutic benefits. In this manuscript, we addressed this challenge using network-based approaches by constructing and analyzing the molecular and signaling networks associated with tumor-immune crosstalk. Our analysis revealed that IL6 is the key regulator responsible for irAEs during ICI therapies. Furthermore, we conducted an integrative network and molecular-level analysis, including virtual screening, of drug libraries, such as the Collection of Open Natural Products (COCONUT) and the Zinc15 FDA-approved library, to identify potential IL6 inhibitors. Subsequently, the compound amprenavir was identified as the best molecule that may disrupt essential interactions between IL6 and IL6R, which are responsible for initiating the signaling cascades underlying irAEs in ICI therapies.


Assuntos
Inibidores de Checkpoint Imunológico , Interleucina-6 , Melanoma , Humanos , Melanoma/tratamento farmacológico , Melanoma/imunologia , Melanoma/metabolismo , Inibidores de Checkpoint Imunológico/efeitos adversos , Inibidores de Checkpoint Imunológico/uso terapêutico , Interleucina-6/metabolismo , Interleucina-6/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos
2.
Radiat Prot Dosimetry ; 200(11-12): 1064-1069, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39016484

RESUMO

The present study is carried out in 42 sampling sites for the measurement of background gamma dose rate in six tehsils of the Bageshwar district that comes under the Kumaun Himalaya, Uttarakhand. The annual effective dose in the pre-monsoon and post-monsoon seasons was estimated from the measured values of the Gamma dose rate. It is found that the minimum and maximum values ranged between 0.01-0.39 mSv per y (Arithmetic Mean = 0.19 mSv per y) in the pre-monsoon and 0.11-0.42 mSv per y (Arithmetic Mean = 0.20 mSv per y) in the post-monsoon season of the year. The finding of the present study shows that the annual effective dose equivalent is higher than the worldwide average value recommended by the United Nations Scientific Committee on the Effects of Atomic Radiation.


Assuntos
Raios gama , Doses de Radiação , Monitoramento de Radiação , Estações do Ano , Poluentes Radioativos do Solo , Índia , Monitoramento de Radiação/métodos , Humanos , Poluentes Radioativos do Solo/análise , Radiação de Fundo
3.
Nanomaterials (Basel) ; 12(10)2022 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-35630938

RESUMO

During the last two decades several nanoscale materials were engineered for industrial and medical applications. Among them carbon nanotubes (CNTs) are the most exploited nanomaterials with global production of around 1000 tons/year. Besides several commercial benefits of CNTs, the fiber-like structures and their bio-persistency in lung tissues raise serious concerns about the possible adverse human health effects resembling those of asbestos fibers. In this review, we present a comparative analysis between CNTs and asbestos fibers using the following four parameters: (1) fibrous needle-like shape, (2) bio-persistent nature, (3) high surface to volume ratio and (4) capacity to adsorb toxicants/pollutants on the surface. We also compare mechanisms underlying the toxicity caused by certain diameters and lengths of CNTs and asbestos fibers using downstream pathways associated with altered gene expression data from both asbestos and CNT exposure. Our results suggest that indeed certain types of CNTs are emulating asbestos fiber as far as associated toxicity is concerned.

4.
Pharmaceutics ; 15(1)2022 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-36678712

RESUMO

Cancer cells have a remarkable ability to evade recognition and destruction by the immune system. At the same time, cancer has been associated with chronic inflammation, while certain autoimmune diseases predispose to the development of neoplasia. Although cancer immunotherapy has revolutionized antitumor treatment, immune-related toxicities and adverse events detract from the clinical utility of even the most advanced drugs, especially in patients with both, metastatic cancer and pre-existing autoimmune diseases. Here, the combination of multi-omics, data-driven computational approaches with the application of network concepts enables in-depth analyses of the dynamic links between cancer, autoimmune diseases, and drugs. In this review, we focus on molecular and epigenetic metastasis-related processes within cancer cells and the immune microenvironment. With melanoma as a model, we uncover vulnerabilities for drug development to control cancer progression and immune responses. Thereby, drug repurposing allows taking advantage of existing safety profiles and established pharmacokinetic properties of approved agents. These procedures promise faster access and optimal management for cancer treatment. Together, these approaches provide new disease-based and data-driven opportunities for the prediction and application of targeted and clinically used drugs at the interface of immune-mediated diseases and cancer towards next-generation immunotherapies.

5.
Cell Mol Life Sci ; 78(23): 7519-7536, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34657170

RESUMO

CCCTC-binding factor (CTCF) plays fundamental roles in transcriptional regulation and chromatin architecture maintenance. CTCF is also a tumour suppressor frequently mutated in cancer, however, the structural and functional impact of mutations have not been examined. We performed molecular and structural characterisation of five cancer-specific CTCF missense zinc finger (ZF) mutations occurring within key intra- and inter-ZF residues. Functional characterisation of CTCF ZF mutations revealed a complete (L309P, R339W, R377H) or intermediate (R339Q) abrogation as well as an enhancement (G420D) of the anti-proliferative effects of CTCF. DNA binding at select sites was disrupted and transcriptional regulatory activities abrogated. Molecular docking and molecular dynamics confirmed that mutations in residues specifically contacting DNA bases or backbone exhibited loss of DNA binding. However, R339Q and G420D were stabilised by the formation of new primary DNA bonds, contributing to gain-of-function. Our data confirm that a spectrum of loss-, change- and gain-of-function impacts on CTCF zinc fingers are observed in cell growth regulation and gene regulatory activities. Hence, diverse cellular phenotypes of mutant CTCF are clearly explained by examining structure-function relationships.


Assuntos
Fator de Ligação a CCCTC/química , Fator de Ligação a CCCTC/metabolismo , Regulação Neoplásica da Expressão Gênica , Mutação , Neoplasias/patologia , Fenótipo , Dedos de Zinco , Apoptose , Fator de Ligação a CCCTC/genética , Proliferação de Células , Humanos , Neoplasias/genética , Neoplasias/metabolismo , Regiões Promotoras Genéticas , Relação Estrutura-Atividade , Células Tumorais Cultivadas
6.
Theranostics ; 10(21): 9620-9643, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32863950

RESUMO

Long non-coding RNAs (lncRNAs) have emerged as integral components of E2F1-regulated gene regulatory networks (GRNs), but their implication in advanced or treatment-refractory malignancy is unknown. Methods: We combined high-throughput transcriptomic approaches with bioinformatics and structure modeling to search for lncRNAs that participate in E2F1-activated prometastatic GRNs and their phenotypic targets in the highly-relevant case of E2F1-driven aggressive bladder cancer (BC). RNA immunoprecipitation was performed to verify RNA-protein interactions. Functional analyses including qRT-PCR, immunoblotting, luciferase assays and measurement of extracellular fluxes were conducted to validate expression and target gene regulation. Results: We identified E2F1-responsive lncRNA-SLC16A1-AS1 and its associated neighboring protein-coding gene, SLC16A1/MCT1, which both promote cancer invasiveness. Mechanistically, upon E2F1-mediated co-transactivation of the gene pair, SLC16A1-AS1 associates with E2F1 in a structure-dependent manner and forms an RNA-protein complex that enhances SLC16A1/MCT1 expression through binding to a composite SLC16A1-AS1:E2F1-responsive promoter element. Moreover, SLC16A1-AS1 increases aerobic glycolysis and mitochondrial respiration and fuels ATP production by fatty acid ß-oxidation. These metabolic changes are accompanied by alterations in the expression of the SLC16A1-AS1:E2F1-responsive gene PPARA, a key mediator of fatty acid ß-oxidation. Conclusions: Our results unveil a new gene regulatory program by which E2F1-induced lncRNA-SLC16A1-AS1 forms a complex with its transcription factor that promotes cancer metabolic reprogramming towards the acquisition of a hybrid oxidative phosphorylation/glycolysis cell phenotype favoring BC invasiveness.


Assuntos
Reprogramação Celular/fisiologia , Fator de Transcrição E2F1/genética , Transportadores de Ácidos Monocarboxílicos/genética , RNA Longo não Codificante/genética , Simportadores/genética , Neoplasias da Bexiga Urinária/genética , Trifosfato de Adenosina/genética , Linhagem Celular Tumoral , Progressão da Doença , Regulação Neoplásica da Expressão Gênica/genética , Glicólise/genética , Humanos , Mitocôndrias/genética , Oxirredução , Regiões Promotoras Genéticas/genética , Ativação Transcricional/genética , Neoplasias da Bexiga Urinária/patologia
7.
Int J Biol Macromol ; 130: 333-341, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-30797811

RESUMO

Gold nanoparticles decorated graphene oxide (Au-rGO) nanocomposite thin films with enhanced electro-active characteristics were prepared and covalently immobilized with uricase (UOx) enzyme for sensitive and selective detection of uric acid (UA). Differential pulse voltammetry (DPV) studies revealed rapid response of fabricated electrode towards UA at low potential (0.228 V) in a wide concentration range of 50-800 µM with a sensitivity of 86.62 ±â€¯0.19 µA mM-1 and very low detection limit of 7.32 ±â€¯0.21 µM. The obtained Michaelis-Menten constant (km) value of 51.75 µM signifies high enzyme kinetics at electrode surface with UA. The developed biosensor was successfully applied to detect UA in human serum samples. Interferences due to components present in the real matrix were evaluated and UA determination in mixed sample was also performed. The fabricated UOx/Au-rGO/ITO biosensor demonstrated high reproducibility and a shelf-life of 6 months indicating the promising future of Au-rGO nanocomposite as an efficient transducer matrix for biosensing applications. The fast response time (1.0 ±â€¯0.6 s) and improved sensor performance is attributed to the synergistic electronic properties of Au-nanoparticles and rGO that provided enhanced electron transfer and high electro-active species surface coverage at Au-rGO nanocomposite.


Assuntos
Técnicas Biossensoriais/métodos , Enzimas Imobilizadas/química , Ouro/química , Nanopartículas Metálicas/química , Urato Oxidase/química , Ácido Úrico/sangue , Técnicas Biossensoriais/instrumentação , Candida/enzimologia , Eletroquímica , Enzimas Imobilizadas/metabolismo , Grafite/química , Humanos , Limite de Detecção , Modelos Moleculares , Conformação Molecular , Óxidos/química , Fatores de Tempo , Urato Oxidase/metabolismo
8.
J Comput Aided Mol Des ; 32(3): 487-496, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29397519

RESUMO

Graphene-based nanomaterials (GBNMs) are widely used in various industrial and biomedical applications. GBNMs of different compositions, size and shapes are being introduced without thorough toxicity evaluation due to the unavailability of regulatory guidelines. Computational toxicity prediction methods are used by regulatory bodies to quickly assess health hazards caused by newer materials. Due to increasing demand of GBNMs in various size and functional groups in industrial and consumer based applications, rapid and reliable computational toxicity assessment methods are urgently needed. In the present work, we investigate the impact of graphene and graphene oxide nanomaterials on the structural conformations of small hepcidin peptide and compare the materials for their structural and conformational changes. Our molecular dynamics simulation studies revealed conformational changes in hepcidin due to its interaction with GBMNs, which results in a loss of its functional properties. Our results indicate that hepcidin peptide undergo severe structural deformations when superimposed on the graphene sheet in comparison to graphene oxide sheet. These observations suggest that graphene is more toxic than a graphene oxide nanosheet of similar area. Overall, this study indicates that computational methods based on structural deformation, using molecular dynamics (MD) simulations, can be used for the early evaluation of toxicity potential of novel nanomaterials.


Assuntos
Grafite/química , Hepcidinas/química , Simulação de Dinâmica Molecular , Nanoestruturas/química , Análise de Componente Principal , Conformação Proteica , Relação Estrutura-Atividade , Propriedades de Superfície
9.
Chem Res Toxicol ; 30(2): 625-634, 2017 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-28029781

RESUMO

Benzanthrone (BA), an oxidized polycyclic aromatic hydrocarbon (PAH), has been found to be a potential health threat to occupational workers involved in dye manufacturing factories. It has been observed that occupational workers become exposed to BA either during manufacturing, pulverization, or storage and developed various kinds of skin diseases like contact dermatitis, itching, erythema, roughness, and foremost, hyperpigmentation. It has been shown that some environmental organic pollutants (POPs) like dioxins, furans, and polychlorinated biphenyls (PCBs) may act as ligands for the aryl hydrocarbon receptor (AhR) and regulate hyperpigmentation. Here, we hypothesized that BA may also act as a ligand for AhR and possibly regulate the melanogenic pathway to induced hyperpigmentation. Our computation results indicate that BA has a high binding affinity toward AhR for the initiation of melanogenic signaling. Following the in silico predictions, we used primary mouse melanocytes (PMMs) and confirmed that exposure to BA (5, 10, and 25 µM) resulted in an increase in AhR expression, tyrosinase activity, and melanin synthesis. Moreover, to study the physiological relevance of these findings, C57BL/6 mice were topically exposed to BA, and enhanced pigmentation and melanin synthesis were observed. Furthermore, the study was extended to assess the mechanistic aspects involved in BA-induced hyperpigmentation in PMMs as well as in mouse skin. Our results suggest that BA exposure initiates AhR signaling and increases tyrosinase enzyme activity and melanin synthesis. Moreover, the genes that regulate the melanin synthesis, such as TRP-1, TRP-2 and the transcription factor MITF, were also found to be increased. Thus, altogether, we suggest that BA-AhR interactions are critical for BA-induced hyperpigmentation.


Assuntos
Benzo(a)Antracenos/toxicidade , Melaninas/metabolismo , Transtornos da Pigmentação/induzido quimicamente , Receptores de Hidrocarboneto Arílico/metabolismo , Transdução de Sinais , Animais , Células Cultivadas , Camundongos , Camundongos Endogâmicos C57BL , Simulação de Acoplamento Molecular
10.
Biomaterials ; 84: 25-41, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26803409

RESUMO

Curcumin (Cur) has been demonstrated to have wide pharmacological window including anti-oxidant and anti-inflammatory properties. However, phototoxicity under sunlight exposure and poor biological availability limits its applicability. We have synthesized biodegradable and non-toxic polymer-poly (lactic-co-glycolic) acid (PLGA) encapsulated formulation of curcumin (PLGA-Cur-NPs) of 150 nm size range. Photochemically free curcumin generates ROS, lipid peroxidation and induces significant UVA and UVB mediated impaired mitochondrial functions leading to apoptosis/necrosis and cell injury in two different origin cell lines viz., mouse fibroblasts-NIH-3T3 and human keratinocytes-HaCaT as compared to PLGA-Cur-NPs. Molecular docking studies suggested that intact curcumin from nanoparticles, bind with BAX in BIM SAHB site and attenuate it to undergo apoptosis while upregulating anti-apoptotic genes like BCL2. Real time studies and western blot analysis with specific phosphorylation inhibitor of ERK1 and AKT1/2/3 confirm the involvement of ERK/AKT signaling molecules to trigger the survival cascade in case of PLGA-Cur-NPs. Our finding demonstrates that low level sustained release of curcumin from PLGA-Cur-NPs could be a promising way to protect the adverse biological interactions of photo-degradation products of curcumin upon the exposure of UVA and UVB. Hence, the applicability of PLGA-Cur-NPs could be suggested as prolonged radical scavenging ingredient in curcumin containing products.


Assuntos
Curcumina/farmacologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Queratinócitos/efeitos da radiação , Ácido Láctico/química , Nanopartículas/química , Ácido Poliglicólico/química , Substâncias Protetoras/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Raios Ultravioleta , Absorção de Radiação , Animais , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos da radiação , Linhagem Celular , Membrana Celular/efeitos dos fármacos , Membrana Celular/efeitos da radiação , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Citoproteção/efeitos dos fármacos , Citoproteção/efeitos da radiação , Quebras de DNA/efeitos dos fármacos , Quebras de DNA/efeitos da radiação , Liberação Controlada de Fármacos , Humanos , Queratinócitos/efeitos dos fármacos , Queratinócitos/enzimologia , Queratinócitos/ultraestrutura , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos da radiação , Camundongos , Simulação de Acoplamento Molecular , Células NIH 3T3 , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/efeitos da radiação , Fármacos Fotossensibilizantes/farmacologia , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos da radiação
11.
Int J Biochem Cell Biol ; 73: 111-126, 2016 04.
Artigo em Inglês | MEDLINE | ID: mdl-26812543

RESUMO

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). This article has been retracted at the request of the Editor-in-Chief. The study is retracted due to image duplication reasons: The article contains an image that had already appeared in Free Radic Res, 48.3 (2014): 333­346. DOI 10.3109/10715762.2013.869324. The images are used in both papers but to conclude something entirely different, and suggested that the images have an entirely different biological meaning and treatment. Duplicating images in this way is ethically not acceptable.


Assuntos
DNA Girase/metabolismo , Ofloxacino/metabolismo , Raios Ultravioleta , Apoptose/efeitos da radiação , Dano ao DNA/efeitos da radiação , DNA Bacteriano/efeitos da radiação , Ligação Proteica/efeitos da radiação
12.
3 Biotech ; 6(1): 39, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28330110

RESUMO

Human papilloma virus (HPV) is the primary etiological agent responsible for cervical cancer in women. Although in total 16 high-risk HPV strains have been identified so far. Currently available commercial vaccines are designed by targeting mainly HPV16 and HPV18 viral strains as these are the most common strains associated with cervical cancer. Because of the high level of antigenic specificity of HPV capsid antigens, the currently available vaccines are not suitable to provide cross-protection from all other high-risk HPV strains. Due to increasing reports of cervical cancer cases from other HPV high-risk strains other than HPV16 and 18, it is crucial to design vaccine that generate reasonable CD8+ T-cell responses for possibly all the high-risk strains. With this aim, we have developed a computational workflow to identify conserved cross-clade CD8+ T-cell HPV vaccine candidates by considering E1, E2, E6 and E7 proteins from all the high-risk HPV strains. We have identified a set of 14 immunogenic conserved peptide fragments that are supposed to provide protection against infection from any of the high-risk HPV strains across globe.

13.
PLoS One ; 9(10): e110041, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25334024

RESUMO

The rapid appearance of resistant malarial parasites after introduction of atovaquone (ATQ) drug has prompted the search for new drugs as even single point mutations in the active site of Cytochrome b protein can rapidly render ATQ ineffective. The presence of Y268 mutations in the Cytochrome b (Cyt b) protein is previously suggested to be responsible for the ATQ resistance in Plasmodium falciparum (P. falciparum). In this study, we examined the resistance mechanism against ATQ in P. falciparum through computational methods. Here, we reported a reliable protein model of Cyt bc1 complex containing Cyt b and the Iron-Sulphur Protein (ISP) of P. falciparum using composite modeling method by combining threading, ab initio modeling and atomic-level structure refinement approaches. The molecular dynamics simulations suggest that Y268S mutation causes ATQ resistance by reducing hydrophobic interactions between Cyt bc1 protein complex and ATQ. Moreover, the important histidine contact of ATQ with the ISP chain is also lost due to Y268S mutation. We noticed the induced mutation alters the arrangement of active site residues in a fashion that enforces ATQ to find its new stable binding site far away from the wild-type binding pocket. The MM-PBSA calculations also shows that the binding affinity of ATQ with Cyt bc1 complex is enough to hold it at this new site that ultimately leads to the ATQ resistance.


Assuntos
Antimaláricos/farmacologia , Atovaquona/farmacologia , Citocromos b/genética , Resistência a Medicamentos/genética , Plasmodium falciparum/genética , Antimaláricos/uso terapêutico , Atovaquona/uso terapêutico , Simulação por Computador , Malária Falciparum/tratamento farmacológico , Mutação
14.
Anal Bioanal Chem ; 405(1): 341-9, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23079953

RESUMO

The present communication describes the preparation and evaluation of a molecularly imprinted polymer (MIP) as a solid-phase extraction (SPE) sorbent and simultaneous ethyl chloroformate (ECF) derivatization and pre-concentration by dispersive liquid-liquid microextraction (DLLME) for the analysis of t,t-muconic acid (t,t-MA) in urine samples using gas chromatography-mass spectrometry. The imprinting polymer was prepared using methacrylic acid as a functional monomer, ethylene glycol dimethacrylate as a cross-linker, 2,2-azobisisobutyronitrile as the initiator and t,t-MA as a template molecule. The imprinted polymer was evaluated for its use as a SPE sorbent by comparing both imprinted and non-imprinted polymers in terms of the recovery of t,t-MA from urine samples. Molecular modelling studies were performed in order to estimate the binding energy and efficiency of the MIP complex formed between the monomer and the t,t-MA. Various factors that can affect the extraction efficiency of MIP, such as the loading, washing and eluting conditions, were optimized; other factors that can affect the derivatization and DLLME pre-concentration were also optimized. MIP in combination with ECF derivatization and DLLME pre-concentration for t,t-MA exhibits good linearity, ranging from 0.125 to 2 µg mL(-1) (R(2) = 0.9971), with limit of detection of 0.037 µg mL(-1) and limit of quantification of 0.109 µg mL(-1). Intra- and inter-day precision was found to be <6%. The proposed method has been proven to be effective and sensitive for the selective pre-concentration and determination of t,t-MA in urine samples of cigarette smokers.


Assuntos
Ésteres do Ácido Fórmico/química , Microextração em Fase Líquida/métodos , Impressão Molecular/métodos , Urinálise/métodos , Calibragem , Relação Dose-Resposta a Droga , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Modelos Moleculares , Polímeros/química , Ligação Proteica , Reprodutibilidade dos Testes , Fumar/urina , Solventes/química , Ácido Sórbico/análogos & derivados , Ácido Sórbico/química , Produtos do Tabaco
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