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1.
Nat Immunol ; 24(5): 869-883, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37081150

RESUMO

To date, no immunotherapy approaches have managed to fully overcome T-cell exhaustion, which remains a mandatory fate for chronically activated effector cells and a major therapeutic challenge. Understanding how to reprogram CD8+ tumor-infiltrating lymphocytes away from exhausted effector states remains an elusive goal. Our work provides evidence that orthogonal gene engineering of T cells to secrete an interleukin (IL)-2 variant binding the IL-2Rßγ receptor and the alarmin IL-33 reprogrammed adoptively transferred T cells to acquire a novel, synthetic effector state, which deviated from canonical exhaustion and displayed superior effector functions. These cells successfully overcame homeostatic barriers in the host and led-in the absence of lymphodepletion or exogenous cytokine support-to high levels of engraftment and tumor regression. Our work unlocks a new opportunity of rationally engineering synthetic CD8+ T-cell states endowed with the ability to avoid exhaustion and control advanced solid tumors.


Assuntos
Linfócitos T CD8-Positivos , Imunoterapia Adotiva , Interleucina-2 , Neoplasias Experimentais , Linfócitos T CD8-Positivos/imunologia , Exaustão das Células T , Linfócitos do Interstício Tumoral/imunologia , Interleucina-2/farmacologia , Interleucina-33 , Engenharia de Proteínas , Feminino , Animais , Camundongos , Camundongos Endogâmicos C57BL , Linhagem Celular Tumoral , Neoplasias Experimentais/terapia , Receptor de Morte Celular Programada 1/metabolismo
2.
NMR Biomed ; : e4935, 2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36945883

RESUMO

We describe the use of nuclear magnetic resonance metabolomics to analyze blood serum samples from healthy individuals (n = 26) and those with metastatic colorectal cancer (CRC; n = 57). The assessment, employing both linear and nonlinear multivariate data analysis techniques, revealed specific metabolite changes associated with metastatic CRC, including increased levels of lactate, glutamate, and pyruvate, and decreased levels of certain amino acids and total fatty acids. Biomarker ratios such as glutamate-to-glutamine and pyruvate-to-alanine were also found to be related to CRC. The study also found that glutamate was linked to progression-free survival and that both glutamate and 3-hydroxybutyrate were risk factors for metastatic CRC. Additionally, gas chromatography coupled to flame-ionization detection was utilized to analyze the fatty acid profile and pathway analysis was performed on the profiled metabolites to understand the metabolic processes involved in CRC. A correlation was also found between the presence of certain metabolites in the blood of CRC patients and certain clinical features.

3.
Eur J Clin Invest ; 53(9): e14006, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37039742

RESUMO

INTRODUCTION: Tocilizumab (TCZ) treatment is associated with dyslipidaemia, including a rise in triglycerides through a mechanism poorly understood. Three molecules play key roles in the regulation of triglyceride metabolism: apolipoprotein C-III (ApoC-III), angiopoietin-like protein 4(ANGPLT4) and lipoprotein lipase (LPL). The aim of this work was to analyse whether the changes in triglycerides shown by TCZ-treated RA patients could stem from the dysregulation that can occur in these regulatory molecules. METHODS: Twenty-seven RA patients included in the TOCRIVAR study who received TCZ (8 mg/kg IV/q4w) were evaluated at baseline and at Weeks 12, 24 and 52 of treatment. ANGPTL4, ApoC-III and LPL, a complete lipid profile and RA disease activity, were analysed at baseline and at each visit. Multivariable linear mixed models were performed to study changes over time in lipids and regulatory molecules. RESULTS: After 24 weeks of TCZ treatment, HDL cholesterol, apolipoprotein A1 and triglycerides increased, whereas lipoprotein (a) decreased significantly from baseline values. However, 1 year after TCZ, no significant differences in lipid pattern were observed with respect to baseline. Serum ANGPTL4 and Apo-CIII levels decreased gradually over time, both being significantly lower than baseline values at Week 52. LPL concentration did not change significantly during TCZ treatment. Remarkably, the elevation of triglycerides at Week 24 maintained its statistical significance after adjusting for the changes in ApoC-III, ANGPTL4 and LPL. CONCLUSION: In TCZ-treated RA patients basal serum levels of ANGPLT4 and ApoC-III, but not LPL, decreased significantly. However, the elevation of triglycerides after TCZ was not related to changes in these regulatory molecules.


Assuntos
Hipertrigliceridemia , Metabolismo dos Lipídeos , Humanos , Apolipoproteína C-III , Triglicerídeos , Hipertrigliceridemia/induzido quimicamente , Lipase Lipoproteica , Lipoproteína(a)
4.
Medicina (Kaunas) ; 57(9)2021 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-34577799

RESUMO

Background and Objectives: The clinical manifestations and course of chronic pancreatitis (CP) are often nonspecific and variable, hampering diagnosis of the risk of exocrine pancreatic insufficiency (EPI). Development of new, reproducible, and non-invasive methods to diagnose EPI is therefore a major priority. The objective of this metabolomic study was to identify novel biomarkers associated with EPI. Materials and Methods: We analyzed 53 samples from patients with CP, 32 with and 21 without EPI, using an untargeted metabolomics workflow based on hydrophilic interaction chromatography coupled to high-resolution mass spectrometry. Principal component and partial least squares-discriminant analyses showed significant between-group differentiation, and univariate and multivariate analyses identified potential candidate metabolites that significantly differed between samples from CP patients with EPI and those without EPI. Results: Excellent results were obtained using a six-metabolic panel to diagnose the presence of EPI in CP patients (area under the ROC curve = 0.785). Conclusions: This study confirms the usefulness of metabolomics in this disease setting, allowing the identification of novel biomarkers to differentiate between the presence and absence of EPI in CP patients.


Assuntos
Insuficiência Pancreática Exócrina , Pancreatite Crônica , Insuficiência Pancreática Exócrina/diagnóstico , Humanos , Espectrometria de Massas , Metabolômica , Análise Multivariada , Pancreatite Crônica/diagnóstico
5.
AAPS PharmSciTech ; 21(5): 178, 2020 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-32591920

RESUMO

Colorectal cancer (CRC) is the third most common cancer worldwide. Its poor response to current treatment options in advanced stages and the need for efficient diagnosis in early stages call for the development of new therapeutic and diagnostic strategies. Some of them are based on the use of nanometric materials as carriers and releasers of therapeutic agents and fluorescent molecules, or even on the utilization of magnetic materials that provide very interesting properties. These nanoformulations present several advantages compared with the free molecular cargo, including increased drug solubility, bioavailability, stability, and tumor specificity. Moreover, tumor multidrug resistance has been decreased in some cases, leading to improved treatment effectiveness by reducing drug dose and potential side effects. Here, we present an updated overview of the latest advances in clinical research, in vivo studies, and patents regarding the application of nanoformulations in the treatment of CRC. Based on the information gathered, a wide variety of nanomaterials are being investigated in clinical research, even in advanced phases, i.e., close to reaching the market. In sum, these novel materials can offer remarkable advantages with respect to current therapies, which could be complemented or even replaced by these nanosystems in the near future.


Assuntos
Ensaios Clínicos como Assunto , Neoplasias Colorretais/tratamento farmacológico , Nanopartículas , Animais , Neoplasias Colorretais/patologia , Humanos , Prognóstico
6.
Medicina (Kaunas) ; 56(10)2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-33036352

RESUMO

Exocrine pancreatic insufficiency (EPI) is defined as the maldigestion of foods due to inadequate pancreatic secretion, which can be caused by alterations in its stimulation, production, transport, or interaction with nutrients at duodenal level. The most frequent causes are chronic pancreatitis in adults and cystic fibrosis in children. The prevalence of EPI is high, varying according to its etiology, but it is considered to be underdiagnosed and undertreated. Its importance lies in the quality of life impairment that results from the malabsorption and malnutrition and in the increased morbidity and mortality, being associated with osteoporosis and cardiovascular events. The diagnosis is based on a set of symptoms, indicators of malnutrition, and an indirect non-invasive test in at-risk patients. The treatment of choice combines non-restrictive dietary measures with pancreatic enzyme replacement therapy to correct the associated symptoms and improve the nutritional status of patients. Non-responders require the adjustment of pancreatic enzyme therapy, the association of proton pump inhibitors, and/or the evaluation of alternative diagnoses such as bacterial overgrowth. This review offers an in-depth overview of EPI in order to support the proper management of this entity based on updated and integrated knowledge of its etiopathogenesis, prevalence, diagnosis, and treatment.


Assuntos
Insuficiência Pancreática Exócrina , Pancreatite Crônica , Criança , Terapia de Reposição de Enzimas , Insuficiência Pancreática Exócrina/diagnóstico , Insuficiência Pancreática Exócrina/epidemiologia , Insuficiência Pancreática Exócrina/etiologia , Humanos , Pâncreas , Qualidade de Vida
7.
Rev Panam Salud Publica ; 41: e55, 2017 Jun 08.
Artigo em Espanhol | MEDLINE | ID: mdl-28614475

RESUMO

OBJECTIVE: Analyze strategies implemented by Ecuador's Ministry of Public Health (MPH) to position the country in the global health agenda during the period 2011-2015 as a result of health sector reform. METHOD: Documentary review and interviews with stakeholders in national and international agencies with respect to positioning in the global health sphere during the study period. RESULTS: It was observed that the reform process produced a new framework to manage international health relations. The MPH implemented strategies and mechanisms to place national health priorities and interests on the global health agenda at bilateral, regional, and global levels. As a result, the country took a leadership role in certain processes and attained recognition at various international forums. CONCLUSIONS: The MPH reform process contributed to recognition and establishment of Ecuador's public policy priorities in the global health agenda through strategies such as giving importance to putting national priorities on the global health agenda, guiding the global health approach exercised by the highest health authority, developing technical capabilities and skills in the International Relations Office, and raising awareness in technical bodies.


Assuntos
Saúde Global , Reforma dos Serviços de Saúde , Equador
8.
Toxicol Appl Pharmacol ; 311: 113-116, 2016 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-27720938

RESUMO

Erlotinib is an epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor that showed activity against pancreatic ductal adenocarcinoma (PDAC). The drug's most frequently reported side effect as a result of EGFR inhibition is skin rash (SR), a symptom which has been associated with a better therapeutic response to the drug. Gene expression profiling can be used as a tool to predict which patients will develop this important cutaneous manifestation. The aim of the present study was to identify which genes may influence the appearance of SR in PDAC patients. The study included 34 PDAC patients treated with erlotinib: 21 patients developed any grade of SR, while 13 patients did not (controls). Before administering any chemotherapy regimen and the development of SR, we collected RNA from peripheral blood samples of all patients and studied the differential gene expression pattern using the Illumina microarray platform HumanHT-12 v4 Expression BeadChip. Seven genes (FAM46C, IFITM3, GMPR, DENND6B, SELENBP1, NOL10, and SIAH2), involved in different pathways including regulatory, migratory, and signalling processes, were downregulated in PDAC patients with SR. Our results suggest the existence of a gene expression profiling significantly correlated with erlotinib-induced SR in PDAC that could be used as prognostic indicator in this patients.


Assuntos
Adenocarcinoma/tratamento farmacológico , Cloridrato de Erlotinib/efeitos adversos , Perfilação da Expressão Gênica , Neoplasias Pancreáticas/tratamento farmacológico , Pele/efeitos dos fármacos , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
9.
J Clin Gastroenterol ; 50(10): 836-848, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27505403

RESUMO

Pancreatic cancer (PC) is a lethal disease representing the seventh most frequent cause of death from cancer worldwide. Resistance of pancreatic tumors to current treatments leads to disappointing survival rates, and more specific and effective therapies are urgently needed. In recent years, immunotherapy has been proposed as a promising approach to the treatment of PC, and encouraging results have been published by various preclinical and clinical studies. This review provides an overview of the latest developments in the immunotherapeutic treatment of PC and summarizes the most recent and important clinical trials.


Assuntos
Imunoterapia , Neoplasias Pancreáticas/terapia , Humanos
10.
Dig Dis Sci ; 59(11): 2714-20, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25069573

RESUMO

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) is a lethal malignancy associated with poor survival rates. Fast detection of PDAC appears to be the most relevant strategy to improve the long-term survival of patients. AIMS: Our objective was to identify new markers in peripheral blood that differentiates between PDAC patients and healthy controls. METHODS: Peripheral blood samples from PDAC patients (n = 18) and controls (n = 18) were analyzed by whole genome cDNA microarray hybridization. The most relevant genes were validated by quantitative real-time PCR (RT-qPCR) in the same set of samples. Finally, our gene prediction set was tested in a blinded set of new peripheral blood samples (n = 30). RESULTS: Microarray studies identified 87 genes differentially expressed in peripheral blood samples from PDAC patients. Four of these genes were selected for analysis by RT-qPCR, which confirmed the previously observed changes. In our blinded validation study, the combination of CLEC4D and IRAK3 predicted the diagnosis of PDAC with 93 % accuracy, with a sensitivity of 86 % and specificity of 100 %. CONCLUSIONS: Peripheral blood gene expression profiling is an useful tool for the diagnosis of PDAC. We present a validated four-gene predictor set (ANKRD22, CLEC4D, VNN1, and IRAK3) that may be useful in PDAC diagnosis.


Assuntos
Carcinoma Ductal Pancreático/sangue , Neoplasias Pancreáticas/sangue , Transcriptoma , Adulto , Idoso , Biomarcadores Tumorais , Carcinoma Ductal Pancreático/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica/fisiologia , Humanos , Leucócitos Mononucleares , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/metabolismo
11.
World J Gastrointest Oncol ; 16(5): 2233-2240, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38764840

RESUMO

BACKGROUND: Metastatic pancreatic ductal adenocarcinoma (PDAC) is a lethal malignancy with dispiriting survival data. Immunotherapy is a promising approach to many cancer types, but achieves poor outcomes in advanced PDAC due to its immunosuppressive tumor microenvironment. We describe a case of metastatic PDAC effectively treated with pembrolizumab. CASE SUMMARY: We report the case of a 67-year-old woman with unresectable locally advanced PDAC, treated with gemcitabine plus nab-paclitaxel followed by radiotherapy plus capecitabine. At nine months, pancreatic tumor progression was observed at the level of the hepatic hilum with the appearance of a new pulmonary nodule suggestive of a second primary, confirmed by left lung biopsy. Systemic immunotherapy was then initiated with pembrolizumab, an immune checkpoint inhibitor targeting programmed cell death protein-1 that covers the two tumor types. The patient showed a complete metabolic response that was maintained throughout the treatment. The patient continues to be disease-free at 5.6 years since the start of immunotherapy. CONCLUSION: These results suggest that the administration of pembrolizumab after chemoradiotherapy has a beneficial effect in patients with metastatic PDAC. To our knowledge, this is the first reported case of a patient with metastatic PDAC and metastatic lung cancer showing such a long-lasting complete response after pembrolizumab treatment without curative surgery. Further studies are required to determine biomarkers that identify PDAC patients most likely to benefit from this immunotherapy.

12.
Metabolites ; 13(7)2023 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-37512579

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest cancers, with five-year survival rates around 10%. The only curative option remains complete surgical resection, but due to the delay in diagnosis, less than 20% of patients are eligible for surgery. Therefore, discovering diagnostic biomarkers for early detection is crucial for improving clinical outcomes. Metabolomics has become a powerful technology for biomarker discovery, and several metabolomic-based panels have been proposed for PDAC diagnosis, but these advances have not yet been translated into the clinic. Therefore, this review focused on summarizing metabolites identified for the early diagnosis of PDAC in the last five years. Bibliographic searches were performed in the PubMed, Scopus and WOS databases, using the terms "Biomarkers, Tumor", "Pancreatic Neoplasms", "Early Diagnosis", "Metabolomics" and "Lipidome" (January 2018-March 2023), and resulted in the selection of fourteen original studies that compared PDAC patients with subjects with other pancreatic diseases. These investigations showed amino acid and lipid metabolic pathways as the most commonly altered, reflecting their potential for biomarker research. Furthermore, other relevant metabolites such as glucose and lactate were detected in the pancreas tissue and body fluids from PDAC patients. Our results suggest that the use of metabolomics remains a robust approach to improve the early diagnosis of PDAC. However, these studies showed heterogeneity with respect to the metabolomics techniques used and further studies will be needed to validate the clinical utility of these biomarkers.

13.
World J Gastrointest Oncol ; 15(2): 268-275, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36908319

RESUMO

Autoimmune pancreatitis (AIP), a chronic inflammation caused by the immune system attacking the pancreas, usually presents imaging and clinical features that overlap with those of pancreatic ductal adenocarcinoma (PDAC). Serum biomarkers, substances that quantitatively change in sera during disease development, are a promising non-invasive tool with high utility for differentiating between these diseases. In this way, the presence of AIP is currently suspected when serum concentrations of immunoglobulin G4 (IgG4) antibody are elevated. However, this approach has some drawbacks. Notably, IgG4 antibody concentrations are also elevated in sera from some patients with PDAC. This review focuses on the most recent and relevant serum biomarkers proposed to differentiate between AIP and PDAC, evaluating the usefulness of immunoglobulins, autoantibodies, chemokines, and cytokines. The proposed serum biomarkers have proven useful, although most studies had a small sample size, did not examine their presence in patients with PDAC, or did not test them in humans. In addition, current evidence suggests that a single serum biomarker is unlikely to accurately differentiate these diseases and that a set of biomarkers will be needed to achieve adequate specificity and sensitivity, either alone or in combination with clinical data and/or radiological images.

14.
Artigo em Inglês | MEDLINE | ID: mdl-38078737

RESUMO

Recently, the classical anatomy of the quadriceps femoris has been questioned after the publication of various morphological variations that differ from the classical description. Therefore, it is necessary to collect information to reach an agreement on its structure. For this, a systematic review was carried out using the Web of Science, Pubmed and ProQuest scientific databases, obtaining a total of 29 papers finally included in the systematic review after being subjected to inclusion and exclusion criteria. The results obtained showed an important and variable prevalence of new configurations described, such as additional heads in the rectus femoris, a different origin of the vastus intermedius, various portions of the vastus lateralis, or the involvement of the vastus medialis in the patellofemoral musculature. For this reason, understanding the anatomy of the quadriceps femoris is a matter that has not yet been fully resolved, with high variability among people that must be studied prior to the application of an invasive and/or surgical procedure.

15.
Int J Nanomedicine ; 18: 5075-5093, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37701822

RESUMO

Introduction: Pancreatic cancer (PC) shows a very poor response to current treatments. Development of drug resistance is one of the causes of the therapy failure, being PARP1 (poly ADP-ribose polymerase 1) a relevant protein in the resistance mechanism. In this work, we have functionalized calcium phosphate-based nanoparticles (NPs) with Olaparib (OLA, a PARP-1 inhibitor) in combination with ascorbic acid (AA), a pro-oxidative agent, to enhance their individual effects. Methods: Amorphous Calcium Phosphate (ACP) NPs were synthesized through a biomimetic approach and then functionalized with OLA and AA (NP-ACP-OLA-AA). After evaluation of the loading capacity and release kinetic, cytotoxicity, cell migration, immunofluorescence, and gene expression assays were performed using pancreatic tumor cell lines. In vivo studies were carried out on tumors derived from the PANC-1 line in NOD SCID gamma (NSG) mice. Results: NP-ACP-OLA-AA was loaded with 13%wt of OLA (75% loading efficiency) and 1% of AA, respectively. The resulting dual nanosystem exhibited a gradual release of OLA and AA, being the latter protected from degradation in solution. This ensured the simultaneous availability of OLA and AA for a longer period, at least, during the entire time of in vitro cell experiments (72 hours). In vitro studies indicated that NP-ACP-OLA-AA showed the best cytotoxic effect outperforming that of the free OLA and a higher genotoxicity and apoptosis-mediated cytotoxic effect in human pancreatic ductal adenocarcinoma cell line. Interestingly, the in vivo assays using immunosuppressed mice with PANC-1-induced tumors revealed that NP-ACP-OLA-AA produced a higher tumor volume reduction (59.1%) compared to free OLA (28.3%) and increased the mice survival. Conclusion: Calcium phosphate NPs, a highly biocompatible and biodegradable system, were an ideal vector for the OLA and AA co-treatment in PC, inducing significant therapeutic benefits relative to free OLA, including cytotoxicity, induction of apoptosis, inhibition of cell migration, tumor growth, and survival.


Assuntos
Neoplasias Pancreáticas , Humanos , Animais , Camundongos , Camundongos SCID , Neoplasias Pancreáticas/tratamento farmacológico , Ácido Ascórbico/farmacologia , Neoplasias Pancreáticas
16.
Front Cardiovasc Med ; 9: 931943, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35958398

RESUMO

Introduction: The incidence of preeclampsia (PE) is about 2-8%, making it one of the leading causes of perinatal morbidity and maternal mortality in the world. Early prophylactic low dose administration (150 mg) of acetylsalicylic acid is associated with a significant reduction in the incidence of early-onset PE, intrauterine growth restriction (IUGR), and neonatal mean stay in the intensive care unit (ICU). Universal implementation of a first-trimester screening system including angiogenic and antiangiogenic markers [the Placental Growth Factor (PlGF) and/or soluble fms-like Tyrosine Kinase-1 (sFlt-1)] has shown a prediction rate of 90% for early-onset PE but entails a high financial cost. The aim of this study is to determine the predictive and preventive capacity of a universal PE first-trimester two-step sequential screening model, determining the PlGF only in patients previously classified as intermediate risk by means of a multivariate model based on resources already used in the standard pregnancy control, in a real clinical setting. We hypothesize that this screening model will achieve similar diagnostic performance as the universal determination of PlGF but at a lower economic cost. Methods and Analysis: This is a prospective, multicentric, cohort study in a real-world clinical setting. Every singleton pregnancy will be recruited at the routine first pregnancy visit. In a first step, the first-trimester risk of PE will be calculated using a multivariate Gaussian distribution model, based on medical history, mean blood pressure, Pregnancy-Associated Plasma Protein A (PAPP-A), and Uterine Artery Doppler Pulsatility Index (UTPI). Patients will be classified into three risk groups for PE: (1) risk ≥ 1/50, high-risk with no further testing (blinded PlGF); (2) risk between 1/51 and 1/500, medium-risk requiring further testing; and (3) risk ≤ 1/501, low-risk with no further testing. In a second step, the PlGF will only be determined in those patients classified as intermediate risk after this first step, and then reclassified into high- or low-risk groups. Prophylactic administration of aspirin (150 mg/day) will be prescribed only in high risk patients. As a secondary objective, sFlt-1 values will be blindly determined in patients with high and intermediate risk to assess its potential performance in the screening for PE. Ethics and Dissemination: The study will be conducted in accordance with the principles of Good Clinical Practice. This study is approved by the Aragon Research Ethics Committee (CEICA) on 3 July 2020 (15/2020). Clinical Trial Registration: ClinicalTrials.gov, identifier: NCT04767438.

17.
Biomed Pharmacother ; 155: 113669, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36113257

RESUMO

Pancreatic cancer (PC) is one of the tumors with the lowest survival rates due to the poor efficacy of the treatments currently used. Gemcitabine (GMZ), one of the chemotherapeutic agents employed when the tumor is unresectable, frequently fails due to the development of drug resistance. PARP1 is a relevant protein in this phenomenon and appears to be related to cancer progression in several types of tumors, including PC. To determine the relevance of PARP1 in the development and treatment of PC, we used the Panc02 cell line to generate modified PC cells with stably inhibited PARP1 expression (Panc02-L) and used GMZ, Olaparib (OLA) and GMZ+OLA as therapeutic strategies. Viability, radiosensitization, angiogenesis, migration, colony formation, TUNEL, cell cycle, multicellular tumorsphere induction and in vivo assays were performed to test the influence of PARP1 inhibition on resistance phenomena and tumor progression. We demonstrated that stable inhibition or pharmacological blockade of PARP1 using OLA-sensitized Panc02 cells against GMZ significantly decreased their IC50, reducing colony formation capacity, cell migration and vessel formation (angiogenesis) in vitro. Furthermore, in vivo analyses revealed that Panc02-L-derived (PARP1-inhibited) tumors showed less growth and lethality, and that GMZ+OLA treatment significantly reduced tumor growth. In conclusion, PARP1 inhibition, both alone and in combination with GMZ, enhances the effectiveness of this chemotherapeutic agent and represents a promising strategy for the treatment of PC.


Assuntos
Antineoplásicos , Neoplasias Pancreáticas , Humanos , Ensaios Antitumorais Modelo de Xenoenxerto , Linhagem Celular Tumoral , Poli(ADP-Ribose) Polimerase-1 , Neoplasias Pancreáticas/patologia , Antineoplásicos/farmacologia , Gencitabina , Neoplasias Pancreáticas
18.
Curr Neuropharmacol ; 19(4): 513-537, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32589560

RESUMO

Temozolomide (TMZ), an oral alkylating prodrug which delivers a methyl group to purine bases of DNA (O6-guanine; N7-guanine and N3-adenine), is frequently used together with radiotherapy as part of the first-line treatment of high-grade gliomas. The main advantages are its high oral bioavailability (almost 100% although the concentration found in the cerebrospinal fluid was approximately 20% of the plasma concentration of TMZ), its lipophilic properties, and small size that confer the ability to cross the blood-brain barrier. Furthermore, this agent has demonstrated activity not only in brain tumors but also in a variety of solid tumors. However, conventional therapy using surgery, radiation, and TMZ in glioblastoma results in a median patient survival of 14.6 months. Treatment failure has been associated with tumor drug resistance. This phenomenon has been linked to the expression of O6-methylguanine-DNA methyltransferase, but the mismatch repair system and the presence of cancer stem-like cells in tumors have also been related to TMZ resistance. The understanding of these mechanisms is essential for the development of new therapeutic strategies in the clinical use of TMZ, including the use of nanomaterial delivery systems and the association with other chemotherapy agents. The aim of this review is to summarize the resistance mechanisms of TMZ and the current advances to improve its clinical use.


Assuntos
Nanotecnologia , Antineoplásicos Alquilantes/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Linhagem Celular Tumoral , Humanos , Temozolomida/farmacologia , Temozolomida/uso terapêutico
19.
World J Gastrointest Oncol ; 13(10): 1263-1287, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34721766

RESUMO

Pancreatic cancer (PC) continues to pose a major clinical challenge. There has been little improvement in patient survival over the past few decades, and it is projected to become the second leading cause of cancer mortality by 2030. The dismal 5-year survival rate of less than 10% after the diagnosis is attributable to the lack of early symptoms, the absence of specific biomarkers for an early diagnosis, and the inadequacy of available chemotherapies. Most patients are diagnosed when the disease has already metastasized and cannot be treated. Cancer interception is vital, actively intervening in the malignization process before the development of a full-blown advanced tumor. An early diagnosis of PC has a dramatic impact on the survival of patients, and improved techniques are urgently needed to detect and evaluate this disease at an early stage. It is difficult to obtain tissue biopsies from the pancreas due to its anatomical position; however, liquid biopsies are readily available and can provide useful information for the diagnosis, prognosis, stratification, and follow-up of patients with PC and for the design of individually tailored treatments. The aim of this review was to provide an update of the latest advances in knowledge on the application of carbohydrates, proteins, cell-free nucleic acids, circulating tumor cells, metabolome compounds, exosomes, and platelets in blood as potential biomarkers for PC, focusing on their clinical relevance and potential for improving patient outcomes.

20.
Biology (Basel) ; 10(8)2021 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-34440035

RESUMO

Human adipose-derived mesenchymal stem cells (hASCs) may be used in some nervous system pathologies, although obtaining an adequate degree of neuronal differentiation is an important barrier to their applicability. This requires a deep understanding of the expression and epigenetic changes of the most important genes involved in their differentiation. We used hASCs from human lipoaspirates to induce neuronal-like cells through three protocols (Neu1, 2, and 3), determined the degree of neuronal differentiation using specific biomarkers in culture cells and neurospheres, and analyzed epigenetic changes of genes involved in this differentiation. Furthermore, we selected the Hoxa-5 gene to determine its potential to improve neuronal differentiation. Our results showed that an excellent hASC neuronal differentiation process using Neu1 which efficiently modulated NES, CHAT, SNAP25, or SCN9A neuronal marker expression. In addition, epigenetic studies showed relevant changes in Hoxa-5, GRM4, FGFR1, RTEL1, METRN, and PAX9 genes. Functional studies of the Hoxa-5 gene using CRISPR/dCas9 and lentiviral systems showed that its overexpression induced hASCs neuronal differentiation that was accelerated with the exposure to Neu1. These results suggest that Hoxa-5 is an essential gene in hASCs neuronal differentiation and therefore, a potential candidate for the development of cell therapy strategies in neurological disorders.

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