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1.
Biotechnol Appl Biochem ; 69(2): 461-468, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33578449

RESUMO

Nonalcoholic fatty liver disease (NAFLD) is the most common hepatic disease. It is rapidly emerging as the frequent cause for liver transplantation with the risk of disease recurrence, even after transplantation. Clinical evidence showed an abnormally altered expression of different peroxisome proliferator-activated receptor (PPAR) isotypes (PPAR-α/γ/δ) in NAFLD with an involvement in the induction of insulin resistance, hepatic steatosis, reactive oxygen species (ROS) formation, and hepatic inflammation. Recently, several dual PPAR-γ/α agonists were developed to simultaneously achieve the insulin-sensitizing effect of PPAR-γ as well as lipid catabolizing effect of PPAR-α. PPAR-α activation could counterbalance the steatogenic and adipogenic effects of PPAR-γ. But most of the drugs were ended in the initial level itself due to harmful adverse effects. In the present review, we discuss the possible mechanism of telmisartan, a typical angiotensin receptor blocker with excellent safety and pharmacokinetic profile, as a PPAR-γ/α dual agonist in the treatment of NAFLD.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Humanos , Fígado , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , PPAR alfa/agonistas , PPAR alfa/metabolismo , PPAR gama/agonistas , PPAR gama/metabolismo , Telmisartan/metabolismo , Telmisartan/farmacologia , Telmisartan/uso terapêutico
2.
Mol Biol Rep ; 48(12): 8075-8095, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34671902

RESUMO

Cancer immunotherapy is a rapidly evolving concept that has been given the tag "fifth pillar" of cancer therapy while radiation therapy, chemotherapy, surgery and targeted therapy remain the other four pillars. This involves the stimulation of the immune system to control tumor growth and it specifically targets the neoplastic cells rather than the normal cells. Conventional chemotherapy has many limitations which include drug resistance, recurrence of cancer and severe adverse effects. Immunology has made major treatment breakthroughs for several cancers such as colorectal cancer, prostate cancer, breast cancer, lung cancer, liver cancer, kidney cancer, stomach cancer, acute lymphoblastic leukaemia etc. Currently, therapeutic strategies harnessing the immune system involve Checkpoint inhibitors, Chimeric antigen receptor T cells (CAR T cells), Monoclonal antibodies, Cancer vaccines, Cytokines, Radio-immunotherapy and Oncolytic virus therapy. The molecular characterization of several tumor antigens (TA) indicates that these TA can be utilized as promising candidates in cancer immunotherapy strategies. Here in this review, we highlight and summarize the different categories of emerging cancer immunotherapies along with the immunologically recognized tumor antigens involved in the tumor microenvironment.


Assuntos
Imunoterapia/métodos , Neoplasias/imunologia , Neoplasias/terapia , Anticorpos Monoclonais/farmacologia , Antígenos de Neoplasias/imunologia , Antígenos de Neoplasias/uso terapêutico , Antineoplásicos Imunológicos/uso terapêutico , Biomarcadores Tumorais , Humanos , Sistema Imunitário/efeitos dos fármacos , Fatores Imunológicos/imunologia , Imunoterapia/tendências , Terapia de Alvo Molecular/métodos , Terapia de Alvo Molecular/tendências , Microambiente Tumoral/efeitos dos fármacos
3.
Malar J ; 19(1): 122, 2020 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-32209094

RESUMO

Please note, following publication of the original article [1], the authors have advised of two errors that are present in the published article.

4.
Malar J ; 18(1): 346, 2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31601218

RESUMO

BACKGROUND: Malaria is one of the deadliest infectious diseases caused by protozoan parasite of Plasmodium spp. Increasing resistance to anti-malarials has become global threat in control of the disease and demands for novel anti-malarial interventions. Naturally-occurring coumarins, which belong to a class of benzo-α-pyrones, found in higher plants and some essential oils, exhibit therapeutic potential against various diseases. However, their limited uptake and non-specificity has restricted their wide spread use as potential drug candidates. METHODS: Two series of carbohydrate fused pyrano[3,2-c]pyranone carbohybrids which were synthesized by combination of 2-C-formyl galactal and 2-C-formyl glucal, with various freshly prepared 4-hydroxycoumarins were screened against Plasmodium falciparum. The anti-malarial activity of these carbohybrids was determined by growth inhibition assay on P. falciparum 3D7 strain using SYBR green based fluorescence assay. Haemolytic activity of carbohybrid 12, which showed maximal anti-malarial activity, was determined by haemocompatibility assay. The uptake of the carbohybrid 12 by parasitized erythrocytes was determined using confocal microscopy. Growth progression assays were performed to determine the stage specific effect of carbohybrid 12 treatment on Pf3D7. In silico studies were conducted to explore the mechanism of action of carbohybrid 12 on parasite microtubule dynamics. These findings were further validated by immunofluorescence assay and drug combination assay. RESULTS: 2-C-formyl galactal fused pyrano[3,2-c]pyranone carbohybrid 12 exhibited maximum growth inhibitory potential against Plasmodium with IC50 value of 5.861 µM and no toxicity on HepG2 cells as well as no haemolysis of erythrocytes. An enhanced uptake of this carbohybrid compound was observed by parasitized erythrocytes as compared to uninfected erythrocytes. Further study revealed that carbohybrid 12 arrests the growth of parasite at trophozoite and schizonts stage during course of progression through asexual blood stages. Mechanistically, it was shown that the carbohybrid 12 binds to α,ß-heterodimer of tubulin and affects microtubule dynamics. CONCLUSION: These findings show carbohydrate group fusion to 4-hydroxycoumarin precursor resulted in pyrano-pyranones derivatives with better solubility, enhanced uptake and improved selectivity. This data confirms that, carbohydrate fused pyrano[3,2-c]pyranones carbohybrids are effective candidates for anti-malarial interventions against P. falciparum.


Assuntos
Antimaláricos/farmacologia , Plasmodium falciparum/efeitos dos fármacos , Simulação por Computador , Cumarínicos/química , Imunofluorescência , Microtúbulos/efeitos dos fármacos
5.
Bioorg Med Chem Lett ; 28(9): 1629-1637, 2018 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-29615339

RESUMO

Development of new class of anti-malarial drugs is an essential requirement for the elimination of malaria. Bioactive components present in medicinal plants and their chemically modified derivatives could be a way forward towards the discovery of effective anti-malarial drugs. Herein, we describe a new class of compounds, 1,3-benzoxazine derivatives of pharmacologically active phytophenols eugenol (compound 3) and isoeugenol (compound 4) synthesised on the principles of green chemistry, as anti-malarials. Compound 4, showed highest anti-malarial activity with no cytotoxicity towards mammalian cells. Compound 4 induced alterations in the intracellular Na+ levels and mitochondrial depolarisation in intraerythrocytic Plasmodium falciparum leading to cell death. Knowing P-type cation ATPase PfATP4 is a regulator for sodium homeostasis, binding of compound 3, compound 4 and eugenol to PfATP4 was analysed by molecular docking studies. Compounds showed binding to the catalytic pocket of PfATP4, however compound 4 showed stronger binding due to the presence of propylene functionality, which corroborates its higher anti-malarial activity. Furthermore, anti-malarial half maximal effective concentration of compound 4 was reduced to 490 nM from 17.54 µM with nanomaterial graphene oxide. Altogether, this study presents anti-plasmodial potential of benzoxazine derivatives of phytophenols and establishes disruption of parasite sodium homeostasis as their mechanism of action.


Assuntos
Antimaláricos/farmacologia , Benzoxazinas/farmacologia , Homeostase/efeitos dos fármacos , Fenóis/farmacologia , Plasmodium falciparum/efeitos dos fármacos , Sódio/farmacologia , Antimaláricos/síntese química , Antimaláricos/química , Benzoxazinas/síntese química , Benzoxazinas/química , Relação Dose-Resposta a Droga , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Simulação de Acoplamento Molecular , Estrutura Molecular , Testes de Sensibilidade Parasitária , Fenóis/química , Plasmodium falciparum/crescimento & desenvolvimento , Sódio/química , Relação Estrutura-Atividade
6.
J Environ Health ; 80(4): E1-E7, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29456264

RESUMO

Children are considered to be a vulnerabletion when it comes to exposures to hazardous substances. Schools, where children spend about one third of their day, are expected to be a safe environment. Yet, there are many hazardous substances in schools that can be inadvertently or intentionally released and harm the health of students and teachers alike. The purpose of this analysis is to characterize acute chemical release incidents in school settings and identify prevention practices. The acute chemical incident surveillance programs of the Agency for Toxic Substances and Disease Registry (ATSDR) captured 24,748 acute chemical release incidents from 14 states that participated during 2008-2013. We examined 335 of these incidents that occurred at schools. While only 1.3% (n = 335) of all chemical incidents reported to ATSDR occurred in schools, these incidents represented a larger part of the total impacts, including 8.5% of incidents with persons injured, 5.7% of evacuations ordered, and 31.1% of people evacuated. Natural gas (21.8%) and mercury (18.2%) were the chemicals most frequently released. Collecting and analyzing data on acute school chemical releases allows stakeholders to target prevention initiatives and provide a school environment safe from these chemical exposures.


Assuntos
Vazamento de Resíduos Químicos , Substâncias Perigosas , Instituições Acadêmicas , Humanos , Gás Natural , Vigilância da População , Estados Unidos
7.
MMWR Morb Mortal Wkly Rep ; 64(22): 601-5, 2015 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-26068562

RESUMO

Large mass casualty gas explosions and catastrophic oil spills are widely reported and receive considerable regulatory attention. Smaller, less catastrophic petroleum product releases are less likely to receive publicity, although study of these incidents might help focus and prioritize prevention efforts. To describe the causes and health impacts of petroleum product release incidents (including gas explosions and oil spills), the Agency for Toxic Substances and Disease Registry (ATSDR) analyzed 2010-2012 data from the National Toxic Substance Incidents Program (NTSIP). A total of 1,369 petroleum product release incidents were reported from seven states, resulting in 512 injuries and 36 deaths. Approximately one fourth of the incidents were associated with utilities, and approximately one fifth were associated with private vehicles or residences. Approximately 10% of petroleum product releases resulted from inadvertent damage to utility lines. Understanding the characteristics of acute petroleum product releases can aid the public and utility workers in the development of preventive strategies and reduce the morbidity and mortality associated with such releases.


Assuntos
Vazamento de Resíduos Químicos/estatística & dados numéricos , Petróleo , Vigilância da População , Ferimentos e Lesões/induzido quimicamente , Humanos , Estados Unidos/epidemiologia , Ferimentos e Lesões/epidemiologia
8.
J Environ Health ; 76(9): 10-5, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24909007

RESUMO

To keep swimming pool water clean and clear, consumers purchase, transport, store, use, and dispose of large amounts of potentially hazardous chemicals. Data about incidents due to the use of these chemicals and the resultant public health impacts are limited. The authors analyzed pool chemical release data from 17 states that participated in the Agency for Toxic Substances and Disease Registry's chemical event surveillance system during 2001-2009. In 400 pool chemical incidents, 60% resulted in injuries. Of the 732 injured persons, 67% were members of the public and 50% were under 18 years old. Incidents occurred most frequently in private residences (39%), but incidents with the most injured persons (34%) occurred at recreational facilities. Human error (71.9%) was the most frequent primary contributing factor, followed by equipment failure (22.8%). Interventions designed to mitigate the public health impact associated with pool chemical releases should target both private pool owners and public pool operators.


Assuntos
Desinfetantes/toxicidade , Substâncias Perigosas/toxicidade , Saúde Pública , Piscinas , Humanos , Gestão da Segurança , Estados Unidos
9.
Am J Prev Med ; 65(3): 385-394, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-36933753

RESUMO

INTRODUCTION: In 2020, suicide was the 12th leading cause of death among adults in the U.S. Previous research has shown that one common precipitating circumstance among adult suicide decedents is experiencing intimate partner problems (IPPs), such as divorce, separation, romantic break-ups, arguments, conflicts, and intimate partner violence. This study examines how precipitating factors differ between IPP- and non-IPP-related suicides. METHODS: In 2022, this study analyzed National Violent Death Reporting System data from adult suicide decedents in 48 states and 2 territories between 2003 and 2020. Multivariable logistic regression models were used to compare precipitating circumstances between IPP- and non-IPP-related suicides, controlling for sociodemographic characteristics. RESULTS: Of the 402,391 suicides, 20% (n=80,717) were known to be IPP-related. Circumstances that significantly increased the odds of IPP-related suicides included a history of suicidal thoughts and attempts and mental health problems (depressed mood, alcohol problem, mental health diagnosis), life stressors (interpersonal violence perpetration and victimization, arguments, financial problems, job problems, family problems), and recent legal problems. Non-IPP-related suicides were more likely to occur among older individuals and to be precipitated by a physical health problem or crime. CONCLUSIONS: The findings can inform prevention strategies that build resiliency and problem-solving skills, strengthen economic support, and identify and assist people at risk for IPP-related suicides. The Centers for Disease Control and Prevention's Suicide Resource for Action and Intimate Partner Violence Prevention resource packages highlight the best available evidence for policies, programs, and practices related to preventing suicides and IPP.


Assuntos
Suicídio , Adulto , Humanos , Estados Unidos/epidemiologia , Suicídio/psicologia , Homicídio , Violência , Causas de Morte , Ideação Suicida , Vigilância da População
10.
Anticancer Agents Med Chem ; 23(8): 882-893, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35440316

RESUMO

OBJECTIVES: Hepatocellular carcinoma (HCC) is the sixth most common type of cancer and accounts for ~90% of cases, with an approximated incidence of >1 million cases by 2025. Currently, the backbone of HCC therapy is the oral multi-kinase inhibitor, Sorafenib, which consists of a Pyridine heterocycle ring system. This review highlights the introspective characteristics of seven anticancer drugs of heterocyclic nature against HCC along with their structural activity relationships and molecular targets. METHODS: Literature collection was performed using PubMed, Google Scholar, SCOPUS, and Cross ref. Additional information was taken from the official website of the FDA and GLOBOCAN. Key findings/ Results: Based on the available literature, approved heterocyclic compounds show promising results against HCC, including Sorafenib (Pyridine), Regorafenib (Pyridine), Lenvatinib (Quinoline), Cabozantinib (Quinoline), Gemcitabine (Pyrimidine), 5-Fluorouracil (Pyrimidine)and Capecitabine (Pyrimidine), their mechanism of action and key aspects regarding its structural activity were included in the review. CONCLUSION: Heterocyclic compounds represent almost two-thirds of the novel drugs approved by FDA between 2010 and 2020 against Cancer. This review summarizes the clinical relevance, mechanism of action, structural activity relationship, and challenges of the seven available anticancer drugs with heterocyclic ring systems against HCC.


Assuntos
Antineoplásicos , Carcinoma Hepatocelular , Neoplasias Hepáticas , Quinolinas , Humanos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Sorafenibe/farmacologia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Compostos de Fenilureia/farmacologia , Compostos de Fenilureia/uso terapêutico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Piridinas/farmacologia , Piridinas/uso terapêutico , Quinolinas/farmacologia , Quinolinas/uso terapêutico , Pirimidinas/uso terapêutico
11.
Recent Pat Anticancer Drug Discov ; 18(3): 268-291, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35616675

RESUMO

Green nanotechnology can offer notable advantages over the conventional drug delivery methods in terms of improved drug stability, drug-carrying capacity, site-specificity, and feasibility to apply different routes of administration with less systemic toxicities. Metal nanoparticles bio fabricated with phytoconstituents and microbial extracts have gained significant interest for the treatment of various solid tumors including hepatocellular carcinoma. Hepatocellular carcinoma (HCC) is an aggressive cancer with a very poor prognosis. The current treatments of HCC fails to provide tumor specificity, causing many systemic toxicities and poor overall survival benefits especially for patients in advanced and terminal stages. A novel therapeutic approach with maximal therapeutic effect and minimum adverse effects are urgently required for HCC patients. Green synthesized metal nanoparticles offer significant anticancer effects along with minimal systemic toxicities because of their site-specific delivery into the tumor microenvironment (TME). Green synthesized metal nanoparticles can therefore be a highly beneficial strategy for the treatment of HCC if properly validated with preclinical and clinical studies. This review focuses on the preclinical evidence of the most widely studied green metal nanoparticles such as green synthesized silver nanoparticles, gold nanoparticles and selenium nanoparticles. We have also summarised the clinical studies and the patents approved for nanoparticles against HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Nanopartículas Metálicas , Humanos , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Ouro/uso terapêutico , Relevância Clínica , Prata/uso terapêutico , Patentes como Assunto , Microambiente Tumoral
12.
Mol Biotechnol ; 2023 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-37782430

RESUMO

Hepatocellular carcinoma (HCC) is the primary malignancy of hepatocytes and the second most common cause of cancer-related mortality across the globe. Despite significant advancements in screening, diagnosis, and treatment modalities for HCC, the mortality-to-incidence ratio remain unacceptably high. A recent study indicates that a minor population of HCCs are AFP negative or express the normal range of AFP levels. Although it is a gold standard and a more reliable biomarker in the advanced stage of HCC and poorly differentiated tumors, it does not serve as a suitable means for screening HCC. AFP plays a significant role in the development and progression of HCC and understanding its role is crucial. By examining the molecular mechanisms involved in AFP-mediated tumorigenesis, we can better understand HCC pathogenesis and identify potential therapeutic targets. This article details the role of alpha-fetoprotein (AFP) in the carcinogenic transformation of hepatocytes. The article also focuses on information about the structure, biosynthesis, and regulation of AFP at the gene level. Additionally, it discusses the immune evasion, metastasis, and control of gene expression that AFP mediates during HCC.

13.
Curr Cancer Drug Targets ; 22(9): 725-740, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35301949

RESUMO

Mucin 1 (MUC 1) is a highly glycosylated tumor-associated antigen (TAA) overexpressed in hepatocellular carcinoma (HCC). This protein plays a critical role in various immune-mediated signaling pathways at its transcriptional and post-transcriptional levels, leading to immune evasion and metastasis in HCC. HCC cells maintain an immune-suppressive environment with the help of immunesuppressive tumor-associated antigens, resulting in a metastatic spread of the disease. The development of intense immunotherapeutic strategies to target tumor-associated antigen is critical to overcoming the progression of HCC. MUC 1 remains the most recognized tumor-associated antigen since its discovery over 30 years ago. A few promising immunotherapies targeting MUC 1 are currently under clinical trials, including CAR-T and CAR-pNK-mediated therapies. This review highlights the biosynthesis, significance, and clinical implication of MUC 1 as an immune target in HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Antígenos de Neoplasias , Biologia , Carcinoma Hepatocelular/patologia , Humanos , Imunoterapia/métodos , Neoplasias Hepáticas/patologia , Mucina-1
14.
Curr Pharm Biotechnol ; 23(2): 201-220, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33593256

RESUMO

Months after WHO declared COVID-19 as a Global Public Health Emergency of International Concern, it does not seem to be flattening the curve as we are still devoid of an effective treatment modality and vaccination is in the first phase in many countries. Amid such uncertainty, being immune is the best strategy to defend against corona attacks. As the whole world is referring back to immune-boosting traditional remedies, interest is rekindled in the Indian system of Medicine, which is gifted with an abundance of herbal medicines as well as remedies. Among them, spices (root, rhizome, seed, fruit, leaf, bud, and flower of various plants used to add taste and flavors to food) are bestowed with immense medicinal potential. A plethora of clinical as well as preclinical studies reported the effectiveness of various spices for various ailments. The potential immune-boosting properties together with their excellent safety profiles are making spices the current choice of phytoresearch as well as the immune-boosting home remedies during these sceptical times. The present review critically evaluates the immune impact of various Indian spices and their potential to tackle the novel coronavirus, with comments on the safety and toxicity aspects of spices.


Assuntos
COVID-19 , Plantas Medicinais , Humanos , Medicina Tradicional , SARS-CoV-2 , Especiarias
15.
Curr Drug Targets ; 22(11): 1288-1316, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33538672

RESUMO

Hepatocellular carcinoma (HCC) is one of the most common solid tumours and the second leading cause of cancer-related mortality worldwide. Advanced-recurrent HCC often requires a systemic drug therapy where multi tyrosine kinase inhibitor, Sorafenib represents the first-line therapy option. But it exhibited very limited survival benefit and tumour response due to the early emergence of drug resistance and drug-related adverse effect. Immunotherapy approaches now being widely studied as an effective alternative treatment for HCC. Several immune checkpoint inhibitors (ICI), such as Nivolumab and Pembrolizumab, are approved as monotherapy in sorafenib-resistant HCC patients. But, the existence of a plethora of immunosuppressive signals in the tumour microenvironment often leads to unsuccessful immunotherapies. In this context, combinatorial immunotherapies are getting much acceptance as a way to improve therapeutic outcomes by blocking immunosuppressive signals in the tumour microenvironment (TME). The combination of Vascular Endothelial Growth Factor (VEGF) inhibitors with ICI resulted in significant synergistic effects in various preclinical and clinical studies. However, the adverse effects associated with current synthetic VEGF inhibitors limit its clinical utility. In this review, we have summarized the potential of phytochemicals, especially the category of flavonoids, alkaloids, glycosides, terpenoids, and coumarin, as the available-affordable-safe-effective repositories of VEGF inhibitors. Their possibilities as an alternative for synthetic VEGF inhibitors by synergistic combination with ICI are reviewed, thereby enhancing patient compliance and survival rates. This review highlights the demand for a detailed investigation of the plausible role of plant-based anti-angiogenic-immunotherapy combination against HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Compostos Fitoquímicos , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Carcinoma Hepatocelular/tratamento farmacológico , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Compostos Fitoquímicos/farmacologia , Sorafenibe , Microambiente Tumoral
16.
Pharmaceuticals (Basel) ; 14(7)2021 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-34358082

RESUMO

Hepatocellular carcinoma (HCC) has emerged as one of the most lethal cancers worldwide because of its high refractoriness and multi-drug resistance to existing chemotherapies, which leads to poor patient survival. Novel pharmacological strategies to tackle HCC are based on oral multi-kinase inhibitors like sorafenib; however, the clinical use of the drug is restricted due to the limited survival rate and significant side effects, suggesting the existence of a primary or/and acquired drug-resistance mechanism. Because of this hurdle, HCC patients are forced through incomplete therapy. Although multiple approaches have been employed in parallel to overcome multidrug resistance (MDR), the results are varying with insignificant outcomes. In the past decade, cancer immunotherapy has emerged as a breakthrough approach and has played a critical role in HCC treatment. The liver is the main immune organ of the lymphatic system. Researchers utilize immunotherapy because immune evasion is considered a major reason for rapid HCC progression. Moreover, the immune response can be augmented and sustained, thus preventing cancer relapse over the post-treatment period. In this review, we provide detailed insights into the immunotherapeutic approaches to combat MDR by focusing on HCC, together with challenges in clinical translation.

17.
J Food Biochem ; 45(7): e13761, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34028054

RESUMO

Chemopreventive approaches with food-derived phytochemicals are progressively rising as a significant aspect of tumor management and control. Herein, we have showcased the major phytoconstituents belonging to the group of flavanoid, as anti-cancer agents used for the treatment and prevention of hepatocellular carcinoma (HCC). Sorafenib is the sole drug used for the treatment of advanced HCC, but its clinical application is limited because of its severe adverse effects and drug resistance. Diet-based chemoprevention seems to be the way forward for this disease of malignant nature. As HCC is derived from a chronic inflammatory milieu, the regular incorporation of bioactive phytochemicals in the diet will confer protection and prevent progression to hepatocarcinogenesis. Many preclinical studies proved that the health benefits of flavonoids confer cytotoxic potential against various types of cancers including hepatocellular carcinoma. As flavonoids with excellent safety profile are abundantly present in common vegetables and fruits, they can be better utilized for chemoprevention and chemosensitization in such chronic condition. This review highlights the plausible role of the eight most promising flavonoids (Curcumin, Kaempferol, Resveratrol, Quercetin, Silibinin, Baicalein, Galangin and Luteolin) as key orchestrators of chemoprevention in hepatocellular carcinoma with preclinical and clinical evidence. An attempt to address the challenges in its clinical translation is also included. This review also provides an insight into the close association of HCC and metabolic disorders which may further decipher the chemopreventive effect of dietary bioactive from a proof of concept to extensive clinical translation. PRACTICAL APPLICATIONS: According to GLOBOCAN 2020 database, it is estimated that 905,677 new cases of liver cancer and approximately 830,180 deaths related to that. The cancer incidence and mortality are almost similar as it is diagnosed at an advanced stage in patients where systemic drug therapy is the sole approach. Due to the emergence of multidrug resistance and drug-related toxicities, most of the patient can not adhere to the therapy regimen. Flavonoids are known to be a potential anticancer agent with an excellent safety profile. These are found to be effective preclinically against hepatocellular carcinoma through modulation of numerous pathways in hepatocarcinogenesis. But, the bioavailability issue, lack of well designed-validated clinical evidence, the possibility of food-drug interaction etc limit its clinical utility. The research inputs mainly to overcome pharmacokinetic issues along with suitable validation of efficacy and toxicity will be a critical point for establishing flavonoids as an effective, safe, affordable therapeutics.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/prevenção & controle , Quimioprevenção , Flavonoides/uso terapêutico , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/prevenção & controle , Resveratrol
18.
FEBS Open Bio ; 9(2): 248-264, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30761251

RESUMO

Lipid-based palmitoylation is a post-translation modification (PTM) which acts as a biological rheostat in life cycle progression of a deadly human malaria parasite, Plasmodium falciparum. P. falciparum palmitoylation is catalyzed by 12 putative palmitoyl acyl-transferase enzymes containing the conserved DHHC-CRD (DHHC motif within a cysteine-rich domain) which can serve as a druggable target. However, the paucity of high-throughput assays has impeded the design of drugs targeting palmitoylation. We have developed a novel strategy which involves engineering of Escherichia coli, a PTM-null system, to enforce ectopic expression of palmitoyl acyl-transferase in order to study Plasmodium-specific palmitoylation and screening of inhibitors. In this study, we have developed three synthetic E. coli strains expressing Plasmodium-specific DHHC proteins (PfDHHC7/8/9). These cells were used for validating acyl-transferase activity via acyl-biotin exchange (ABE) and clickable chemistry methods. E. coli proteome was found to be palmitoylated in PfDHHC-expressing clones, suggesting that plasmodium DHHC can catalyze palmitoylation of E. coli proteins. Upon treatment with generic inhibitor 2-bromopalmitate (2-BMP), a predominant reduction in palmitic acid incorporation is detected. Overall, these findings suggest that synthetic E. coli strains expressing PfDHHCs can enforce global palmitoylation in the E. coli proteome. Interestingly, this finding was corroborated by our in silico palmitoylome profiling, which revealed that out of the total E. coli proteome, 108 proteins were predicted to be palmitoylated as represented by the presence of three cysteine consensus motifs (cluster type I, II, III). In summary, our study reports a proof of concept for screening of chemotherapeutics targeting the palmitoylation machinery using a high-throughput screening platform.


Assuntos
Aciltransferases/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Escherichia coli/efeitos dos fármacos , Engenharia Genética , Ensaios de Triagem em Larga Escala , Ácido Palmítico/antagonistas & inibidores , Plasmodium falciparum/efeitos dos fármacos , Aciltransferases/metabolismo , Biocatálise , Química Click , Inibidores Enzimáticos/química , Escherichia coli/genética , Escherichia coli/metabolismo , Simulação de Acoplamento Molecular , Ácido Palmítico/metabolismo , Plasmodium falciparum/crescimento & desenvolvimento , Plasmodium falciparum/metabolismo
19.
Front Neurol ; 9: 266, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29755398

RESUMO

Microglial cells form a context-dependent network of brain immunoeffector cells. Despite their indispensable roles, unresolved questions exist around biomarker discovery relevant to their cellular localization, self-renewing potential, and brain developmental dynamics. To resolve the existent gap in the annotation of candidate biomarkers, we conducted a meta-analysis of brain cells using available high-throughput data sets for deciphering microglia-specific expression profiles. We have identified 3,290 significant genes specific to microglia and further selected the top 20 dysregulated genes on the basis of p-value and log2FC. To this list, we added 7 known microglia-specific markers making the candidate list comprising 27 genes for further downstream analyses. Next, we established a connectome of these potential markers with their putative protein partners, which demonstrated strong associations of upregulated genes like Dedicator of cytokinesis 2 (DOCK2) with early/mature microglial markers such as Sphingosine kinase 1 (SPHK1), CD68, and CD45. To elucidate their respective brain anatomical location, we deconvoluted the BrainSpan Atlas expression data. This analysis showed high expression of the majority of candidate genes in microglia-dense regions (Amygdala, Hippocampus, Striatum) in the postnatal brain. Furthermore, to decipher their localized expression across brain ages, we constructed a developmental dynamics map (DDM) comprising extensive gene expression profiles throughout prenatal to postnatal stages, which resulted in the discovery of novel microglia-specific gene signatures. One of the interesting readout from DDM is that all the microglia-dense regions exhibit dynamic regulation of few genes at 37 post conception week (pcw), the transition period between pre- and postnatal stages. To validate these findings and correlate them as potential biomarkers, we analyzed the expression of corresponding proteins in hESC-derived human microglia precursors. The cultured microglial precursors showed expression of Pentraxin 3 (PTX3) and SPHK1 as well as several known markers like CD68, Allograft inflammatory factor 1 (AIF1/IBA1). In summary, this study has furnished critical insights into microglia dynamics across human brain ages and cataloged potential transcriptomic fingerprints that can be further exploited for designing novel neurotherapeutics.

20.
Artigo em Inglês | MEDLINE | ID: mdl-29977865

RESUMO

Palmitoylation has been recently identified as an important post-translational rheostat for controlling protein function in eukaryotes. However, the molecular machinery underlying palmitoylation remains unclear in the neglected tropical parasite, Leishmania donovani. Herein, we have identified a catalog of 20 novel palmitoyl acyltransferases (PATs) and characterized the promastigote-specific PAT (LdPAT4) containing the canonical Asp-His-His-Cys (DHHC) domain. Immunofluorescence analysis using in-house generated LdPAT4-specific antibody demonstrated distinct expression of LdPAT4 in the flagellar pocket of promastigotes. Using metabolic labeling-coupled click chemistry method, the functionality of this recombinant enzyme could be authenticated in E. coli strain expressing LdPAT4-DHHC domain. This was evident by the cellular uptake of palmitic acid analogs, which could be successfully inhibited by 2-BMP, a PAT-specific inhibitor. Using CSS-Palm based in-silico proteomic analysis, we could predict up to 23 palmitoylated sites per protein in the promastigotes, and further identify distinctive palmitoylated protein clusters involved in microtubule assembly, flagella motility and vesicular trafficking. To highlight, proteins such as Flagellar Member proteins (FLAM1, FLAM5), Intraflagellar Transport proteins (IFT88), and flagellar motor assembly proteins including the Dynein family were found to be enriched. Furthermore, analysis of global palmitoylation in promastigotes using Acyl-biotin exchange purification identified a set of S-palmitoylated proteins overlapping with the in-silico proteomics data. The attenuation of palmitoylation using 2-BMP demonstrated several phenotypic alterations in the promastigotes including distorted morphology, reduced motility (flagellar loss or slow flagellar beating), and inefficient invasion of promastigotes to host macrophages. These analyses confirm the essential role of palmitoylation in promastigotes. In summary, the findings suggest that LdPAT4 acts as a functional acyltransferase that can regulate palmitoylation of proteins involved in parasite motility and invasion, thus, can serve as a potential target for designing chemotherapeutics in Visceral Leishmaniasis.


Assuntos
Aciltransferases/química , Leishmania donovani/enzimologia , Lipoilação/fisiologia , Aciltransferases/genética , Aciltransferases/isolamento & purificação , Sequência de Bases , Proteína Morfogenética Óssea 2/antagonistas & inibidores , Escherichia coli/genética , Expressão Gênica , Ontologia Genética , Genes de Protozoários , Humanos , Leishmania donovani/genética , Leishmania donovani/patogenicidade , Macrófagos/parasitologia , Simulação de Acoplamento Molecular , Transporte Proteico , Proteômica/métodos , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo , Proteínas Recombinantes , Alinhamento de Sequência , Fator de Crescimento Transformador beta/antagonistas & inibidores
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