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1.
EMBO Rep ; 20(11): e48143, 2019 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-31535451

RESUMO

NPC is a neurodegenerative disorder characterized by cholesterol accumulation in endolysosomal compartments. It is caused by mutations in the gene encoding NPC1, an endolysosomal protein mediating intracellular cholesterol trafficking. Cognitive and psychiatric alterations are hallmarks in NPC patients pointing to synaptic defects. However, the role of NPC1 in synapses has not been explored. We show that NPC1 is present in the postsynaptic compartment and is locally translated during LTP. A mutation in a region of the NPC1 gene commonly altered in NPC patients reduces NPC1 levels at synapses due to enhanced NPC1 protein degradation. This leads to shorter postsynaptic densities, increased synaptic cholesterol and impaired LTP in NPC1nmf164 mice with cognitive deficits. NPC1 mediates cholesterol mobilization and enables surface delivery of CYP46A1 and GluA1 receptors necessary for LTP, which is defective in NPC1nmf164 mice. Pharmacological activation of CYP46A1 normalizes synaptic levels of cholesterol, LTP and cognitive abilities, and extends life span of NPC1nmf164 mice. Our results unveil NPC1 as a regulator of cholesterol dynamics in synapses contributing to synaptic plasticity, and provide a potential therapeutic strategy for NPC patients.


Assuntos
Colesterol 24-Hidroxilase/metabolismo , Colesterol/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Potenciação de Longa Duração , Doença de Niemann-Pick Tipo C/genética , Doença de Niemann-Pick Tipo C/metabolismo , Animais , Modelos Animais de Doenças , Humanos , Imuno-Histoquímica , Camundongos , Camundongos Knockout , Modelos Biológicos , Proteína C1 de Niemann-Pick , Biossíntese de Proteínas , Receptores de AMPA/metabolismo , Sinapses/metabolismo
2.
Stat Med ; 40(2): 287-298, 2021 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-33086432

RESUMO

In an infectious disease cohort study, individuals who have been infected with a pathogen are often recruited for follow up. The period between infection and the onset of symptomatic disease, referred to as the incubation period, is of interest because of its importance on disease surveillance and control. However, the incubation period is often difficult to ascertain due to the uncertainty associated with asymptomatic infection onset time. An additional complication is that the observed infected subjects are likely to have longer incubation periods due to the prevalent sampling. In this article, we demonstrate how to estimate the distribution of the incubation period with the uncertain infection onset, subject to left-truncation and right-censoring. We employ a family of sufficiently general parametric models, the generalized odds-rate class of regression models, for the underlying incubation period and its correlation with covariates. In simulation studies, we assess the finite sample performance of the model fitting and hazard function estimation. The proposed method is illustrated on data from the HIV/AIDS study on injection drug users admitted to a detoxification program in Badalona, Spain.


Assuntos
Síndrome da Imunodeficiência Adquirida , Estudos de Coortes , Simulação por Computador , Humanos , Projetos de Pesquisa , Espanha
3.
Biom J ; 61(2): 299-318, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30548669

RESUMO

We present a method to fit a mixed effects Cox model with interval-censored data. Our proposal is based on a multiple imputation approach that uses the truncated Weibull distribution to replace the interval-censored data by imputed survival times and then uses established mixed effects Cox methods for right-censored data. Interval-censored data were encountered in a database corresponding to a recompilation of retrospective data from eight analytical treatment interruption (ATI) studies in 158 human immunodeficiency virus (HIV) positive combination antiretroviral treatment (cART) suppressed individuals. The main variable of interest is the time to viral rebound, which is defined as the increase of serum viral load (VL) to detectable levels in a patient with previously undetectable VL, as a consequence of the interruption of cART. Another aspect of interest of the analysis is to consider the fact that the data come from different studies based on different grounds and that we have several assessments on the same patient. In order to handle this extra variability, we frame the problem into a mixed effects Cox model that considers a random intercept per subject as well as correlated random intercept and slope for pre-cART VL per study. Our procedure has been implemented in R using two packages: truncdist and coxme, and can be applied to any data set that presents both interval-censored survival times and a grouped data structure that could be treated as a random effect in a regression model. The properties of the parameter estimators obtained with our proposed method are addressed through a simulation study.


Assuntos
Bioestatística/métodos , HIV/genética , RNA Viral/genética , Fármacos Anti-HIV/farmacologia , Feminino , HIV/efeitos dos fármacos , Humanos , Masculino , Modelos de Riscos Proporcionais , Fatores Sexuais
4.
J Antimicrob Chemother ; 73(9): 2452-2459, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-29860519

RESUMO

Background: Osteoporotic fractures still remain very infrequent and physicians rarely evaluate bone health. We wanted to assess the magnitude of this problem in the near future by determining the risk and likelihood of progression to osteoporosis. Methods: We estimated the risk of progression to osteopenia/osteoporosis among HIV-infected patients with at least 2 DXA scans (3726 scans from 875 patients). Time-non-homogeneous bidirectional multistate models based on three states (normal bone mineral density, osteopenia and osteoporosis) were used to model the progression of bone mineral density as a function of age and to study the association between the risk of bone loss and antiretroviral use. Results: The HRs associated with age (>45 versus ≤45 years) were: (i) from normal bone mineral density to osteopenia, 0.71 (95% CI 0.45-1.11) for men and 1.06 (95% CI 0.55-2.05) for women; and (ii) from osteopenia to osteoporosis, 0.83 (95% CI 0.51-1.35) for men and 0.99 (95% CI 0.38-2.56) for women. The transition probabilities from osteopenia to osteoporosis over 10 years among men aged 30 and 50 years were 14.9% (95% CI 10.5%-20.4%) and 19% (95% CI 14.3%-24.3%), respectively; and for women, 6.9% (95% CI 3.1%-14.4%) and 30.1% (95% CI 19.8%-41.8%), respectively. An increased osteoporosis risk was observed for PIs and PIs + tenofovir disoproxil fumarate; darunavir was associated with a higher risk of osteoporosis among men (HR 3.9; 95% CI 2-7.5) and women (HR 4.5; 95% CI 1.4-14.7); and atazanavir was associated with a higher risk of osteoporosis among women (HR 4.2; 95% CI 1.3-14). Conclusions: Our results highlight the importance of monitoring bone mineral density given the high probability of progression to osteopenia/osteoporosis, especially in women. In the future, changes in antiretrovirals other than tenofovir, such as PIs, should be recommended to reduce the risk of fracture.


Assuntos
Infecções por HIV/tratamento farmacológico , Inibidores da Protease de HIV/efeitos adversos , Osteoporose/induzido quimicamente , Osteoporose/epidemiologia , Absorciometria de Fóton , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Densidade Óssea/efeitos dos fármacos , Feminino , Inibidores da Protease de HIV/administração & dosagem , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Medição de Risco , Fatores Sexuais
5.
Int Arch Occup Environ Health ; 91(6): 725-734, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29845565

RESUMO

PURPOSE: During recent decades, several reports have suggested a decrease in semen quality and DNA damage due in part to environmental toxicants and industrial chemicals. Among these xenobiotics, polycyclic aromatic hydrocarbons (PAHs) are of particular concern because of their remarkable mutagenic and carcinogenic properties and because several experimental and epidemiological studies have reported adverse effects of PAHs on male reproductive health and DNA structure. The aim of the study was to evaluate the association between 1-hydroxypyrene (1-OHP) urinary levels and sperm quality, DNA damage and the frequency of CYP1A1, GSTT1, and GSTM1 polymorphisms. METHODS: Semen, urine and blood samples were taken for sperm-quality assessment, 1-OHP urinary level measurement, DNA damage evaluation and polymorphism frequency analysis of three genes implicated in PAH metabolism in a total of 70 Mexican subjects exposed and nonexposed to PAHs. RESULTS: A significant decrease in sperm quality and increased DNA damage were registered in occupationally exposed volunteers. Polymorphisms modified the 1-OHP urinary levels; however, no associations were found between them. Inverse associations were registered between the sperm concentration/mL and 1-OHP levels and between tail lengths and the GSMT1 null genotype. CONCLUSIONS: Our data showed an inverse association between 1-OHP urinary levels and both sperm quality and the DNA integrity. Additionally, the heterozygote variants of CYP1A1-m1 and CYP1A1-m2 significantly increased the urinary excretion of 1-OHP, and the GSTM1 null variant was inversely associated with the comet parameters evaluated.


Assuntos
Citocromo P-450 CYP1A1/genética , Exposição Ocupacional/efeitos adversos , Hidrocarbonetos Policíclicos Aromáticos/efeitos adversos , Pirenos/urina , Espermatozoides/fisiologia , Adolescente , Adulto , Ensaio Cometa , Citocromo P-450 CYP1A1/urina , Dano ao DNA , Glutationa Transferase/sangue , Glutationa Transferase/genética , Humanos , Entrevistas como Assunto , Modelos Lineares , Masculino , México , Pessoa de Meia-Idade , Hidrocarbonetos Policíclicos Aromáticos/sangue , Hidrocarbonetos Policíclicos Aromáticos/urina , Polimorfismo Genético , Análise do Sêmen , Adulto Jovem
6.
Am J Epidemiol ; 185(9): 832-841, 2017 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-28402501

RESUMO

Although composite endpoints (CE) are common in clinical trials, the impact of the relationship between the components of a binary CE on the sample size requirement (SSR) has not been addressed. We performed a computational study considering 2 treatments and a CE with 2 components: the relevant endpoint (RE) and the additional endpoint (AE). We assessed the strength of the components' interrelation by the degree of relative overlap between them, which was stratified into 5 groups. Within each stratum, SSR was computed for multiple scenarios by varying the events proportion and the effect of the therapy. A lower SSR using CE was defined as the best scenario for using the CE. In 25 of 66 scenarios the degree of relative overlap determined the benefit of using CE instead of the RE. Adding an AE with greater effect than the RE leads to lower SSR using the CE regardless of the AE proportion and the relative overlap. The influence of overlapping decreases when the effect on RE increases. Adding an AE with lower effect than the RE constitutes the most uncertain situation. In summary, the interrelationship between CE components, assessed by the relative overlap, can help to define the SSR in specific situations and it should be considered for SSR computation.


Assuntos
Estudos Epidemiológicos , Tamanho da Amostra , Métodos Epidemiológicos , Humanos
7.
J Appl Toxicol ; 37(10): 1195-1202, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28524356

RESUMO

The Hippo pathway regulates cell proliferation and apoptosis and it has been noted that loss of critical components of this pathway can lead to uncontrolled cell growth. Yes-associated protein (YAP) is an important component of this Hippo pathway because YAP is the nuclear effector of the Hippo tumor suppressor pathway and it is crucial for the response to oxidative stress induced by cellular process and by different xenobiotics, including arsenic. It has been proposed that YAP dysregulation can contribute to a malignant cellular phenotype acting as both a tumor suppressor and an oncogene. The aim of the study was to assess and compare the expression of YAP in neoplastic and non-neoplastic breast tissue of women chronically exposed to arsenic through drinking water. YAP expression was assessed by immunohistochemistry in 120 breast biopsies from women with breast cancer and from women with other non-neoplastic breast pathologies. Arsenic concentration was quantified in urine. The results disclosed a significant lower percentage of cytoplasm YAP expression in cases and that YAP high-intensity staining in the cytoplasm but not in the nucleus decreases the risk for breast cancer. In conclusion, our overall data suggest that YAP may act as a tumor suppressor protein because their reduced expression in cases, which can induce an environment favorable for inhibition of apoptosis and promoting cellular proliferation by increasing genetic instability of cells, which might contribute to the pathogenesis of cancer. Copyright © 2017 John Wiley & Sons, Ltd.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Arsênio/urina , Neoplasias da Mama/genética , Fosfoproteínas/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Adulto , Antropometria , Arsênio/toxicidade , Mama/efeitos dos fármacos , Mama/metabolismo , Neoplasias da Mama/induzido quimicamente , Linhagem Celular Tumoral , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Proliferação de Células/efeitos dos fármacos , Estudos Transversais , Citoplasma/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Estilo de Vida , Pessoa de Meia-Idade , Fosfoproteínas/genética , Fatores Socioeconômicos , Inquéritos e Questionários , Fatores de Transcrição , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo , Proteínas de Sinalização YAP
8.
J Biopharm Stat ; 26(5): 880-98, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26400217

RESUMO

The decision on the primary endpoint in a randomized clinical trial is of paramount importance and the combination of several endpoints might be a reasonable choice. Gómez and Lagakos (2013) have developed a method that quantifies how much more efficient it could be to use a composite instead of an individual relevant endpoint. From the information provided by the frequencies of observing the component endpoints in the control group and by the relative treatment effects on each individual endpoint, the asymptotic relative efficiency (ARE) can be computed. This article presents the applicability of the ARE method as a practical and objective tool to evaluate which components, among the plausible ones, are more efficient in the construction of the primary endpoint. The method is illustrated with two real cardiovascular clinical trials and is extended to allow for different dependence structures between the times to the individual endpoints. The influence of this choice on the recommendation on whether or not to use the composite endpoint as the primary endpoint for the investigation is studied. We conclude that the recommendation between using the composite or the relevant endpoint only depends on the frequencies of the endpoints and the relative effects of the treatment.


Assuntos
Determinação de Ponto Final , Inquéritos e Questionários , Grupos Controle , Interpretação Estatística de Dados , Humanos
9.
Salud Publica Mex ; 56(2): 206-12, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25014427

RESUMO

OBJECTIVE: To assess whether in Mexican population the frequencies of ATM polymorphisms IVS24-9delT, IVS38-8-T>C, and 5557G>A in breast cancer (BC) cases and healthy controls were different from those found in other countries. MATERIALS AND METHODS: Frequencies of polymorphisms conferring BC risk IVS24-9delT, IVS38-8T>C, and 5557G>A were analyzed by PCR-RFLP in 94 patients with familial and/or early onset BC, and 97 healthy controls randomly selected. Allele frequencies analysis was done using χ(2) and Hardy-Weinberg test. RESULTS: Frequencies of heterozygous were: for 5557G>A, 13% cases, 0%controls (p=0.0009); for IVS24-9delT, 21% cases, 8% controls (p=0.0122); for IVS38-8T>C, only one case. 5557G>A and IVS24-9delT were more frequent in cases than in controls. The allelic frequencies found in 5557G>A are similar to those described by González-Hormazábal in Chile. CONCLUSION: The similarity of results in this polymorphism between Chilean and Mexican populations may be due to both being crossbred with an Amerindian-Spanish component, while differences may be due to fact that Chilean population has a greater European component than Mexican's.


Assuntos
Proteínas Mutadas de Ataxia Telangiectasia/genética , Neoplasias da Mama/genética , Polimorfismo de Nucleotídeo Único , Adulto , Chile , Feminino , Humanos , México , Pessoa de Meia-Idade
10.
PeerJ ; 12: e16861, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38361769

RESUMO

Background: Knowledge of the physical and environmental conditions that may limit the migration of invasive species is crucial to assess the potential for expansion outside their native ranges. The cactus moth, Cactoblastis cactorum, is native to South America (Argentina, Paraguay, Uruguay and Brazil) and has been introduced and invaded the Caribbean and southern United States, among other regions. In North America there is an ongoing process of range expansion threatening cacti biodiversity of the genus Opuntia and the commercial profits of domesticated Opuntia ficus-indica. Methods: To further understand what influences the distribution and genetic structure of this otherwise important threat to native and managed ecosystems, in the present study we combined ecological niche modeling and population genetic analyses to identify potential environmental barriers in the native region of Argentina. Samples were collected on the host with the wider distribution range, O. ficus-indica. Results: Significant genetic structure was detected using 10 nuclear microsatellites and 24 sampling sites. At least six genetic groups delimited by mountain ranges, salt flats and wetlands were mainly located to the west of the Dry Chaco ecoregion. Niche modeling supports that this region has high environmental suitability where the upper soil temperature and humidity, soil carbon content and precipitation were the main environmental factors that explain the presence of the moth. Environmental filters such as the upper soil layer may be critical for pupal survival and consequently for the establishment of populations in new habitats, whereas the presence of available hosts is a necessary conditions for insect survival, upper soil and climatic characteristics will determine the opportunities for a successful establishment.


Assuntos
Mariposas , Opuntia , Animais , Estados Unidos , Mariposas/genética , Argentina , Ecossistema , Brasil
11.
Clin Transl Oncol ; 26(5): 1077-1088, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38064014

RESUMO

Drug repurposing of widely prescribed patent-off and cheap drugs may provide affordable drugs for cancer treatment. Nevertheless, many preclinical studies of cancer drug repurposing candidates use in vitro drug concentrations too high to have clinical relevance. Hence, preclinical studies must use clinically achievable drug concentrations. In this work, several FDA-approved cancer drugs are analyzed regarding the correlation between the drug inhibitory concentrations 50% (IC50) tested in cancer cell lines and their corresponding peak serum concentration (Cmax) and area under the curve (AUC) reported in clinical studies of these drugs. We found that for most targeted cancer drugs, the AUC and not the Cmax is closest to the IC50; therefore, we suggest that the initial testing of candidate drugs for repurposing could select the AUC pharmacokinetic parameter and not the Cmax as the translated drug concentration for in vitro testing. Nevertheless, this is a suggestion only as experimental evidence does not exist to prove this concept. Studies on this issue are required to advance in cancer drug repurposing.

12.
Am J Cancer Res ; 14(6): 3068-3082, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39005694

RESUMO

Lymphoma is a disease that affects countless lives each year. In order to combat this disease, researchers have been exploring the potential of DNMTi and HDACi drugs. These drugs target the cellular processes that contribute to lymphomagenesis and treatment resistance. Our research evaluated the effectiveness of a combination of two such drugs, hydralazine (DNMTi) and valproate (HDACi), in B-cell and T-cell lymphoma cell lines. Here we show that the combination of hydralazine and valproate decreased the viability of cells over time, leading to the arrest of cell-cycle and apoptosis in both B and T-cells. This combination of drugs proved to be synergistic, with each drug showing significant growth inhibition individually. Microarray analyses of HuT 78 and Raji cells showed that the combination of hydralazine and valproate resulted in the up-regulation of 562 and 850 genes, respectively, while down-regulating 152 and 650 genes. Several proapoptotic and cell cycle-related genes were found to be up-regulated. Notably, three and five of the ten most up-regulated genes in HuT 78 and Raji cells, respectively, were related to immune function. In summary, our study suggests that the combination of hydralazine and valproate is an effective treatment option for both B- and T-lymphomas. These findings are highly encouraging, and we urge further clinical evaluation to validate our research and potentially improve lymphoma treatment.

13.
Front Biosci (Landmark Ed) ; 29(1): 16, 2024 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-38287802

RESUMO

BACKGROUND: The SLC5A8 gene is silenced in various types of cancer, including cervical cancer; we recently demonstrated that the SLC5A8 gene is also silenced in cervical cancer by hypermethylation of the CpG island in the gene promoter. This study aims to analyze whether SLC5A8 could be a tumor suppressor in cervical cancer. METHODS: After ectopic expressing SLC5A8 in the HeLa cell line, we evaluated its effects on cell behavior both in vitro and in vivo by Confocal immunofluorescence, cell proliferation, migration assays, and xenograft transplants. RESULTS: Overexpression of SLC5A8 in the HeLa cell line decreased its proliferation by arresting cancer cells in the G1 phase and inhibiting cellular migration. Furthermore, we observed that pyruvate increased the SLC5A8 effect, inducing S-phase arrest and inhibiting the entry into mitosis. SLC5A8 decreased tumor growth in xenograft transplants, significantly reducing the volume and tumor weight at 35 days of analysis. CONCLUSIONS: In summary, our results indicate that SLC5A8 has a role as a tumor suppressor in cervical cancer.


Assuntos
Transportadores de Ácidos Monocarboxílicos , Neoplasias do Colo do Útero , Feminino , Humanos , Linhagem Celular Tumoral , Genes Supressores de Tumor , Células HeLa , Transportadores de Ácidos Monocarboxílicos/genética , Ácido Pirúvico , Neoplasias do Colo do Útero/genética , Animais
14.
Expert Rev Anticancer Ther ; : 1-13, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38913911

RESUMO

INTRODUCTION: The pharmacological treatment of cancer has evolved from cytotoxic to molecular targeted therapy. The median survival gains of 124 drugs approved by the FDA from 2003 to 2021 is 2.8 months. Targeted therapy is based on the somatic mutation theory, which has some paradoxes and limitations. While efforts of targeted therapy must continue, we must study newer approaches that could advance therapy and affordability for patients. AREAS COVERED: This work briefly overviews how cancer therapy has evolved from cytotoxic chemotherapy to current molecular-targeted therapy. The limitations of the one-target, one-drug approach considering cancer as a robust system and the basis for multitargeting approach with polypharmacotherapy using repurposing drugs. EXPERT OPINION: Multitargeted polypharmacotherapy for cancer with repurposed drugs should be systematically investigated in preclinical and clinical studies. Remarkably, most of these proposed drugs already have a long history in the clinical setting, and their safety is known. In principle, the risk of their simultaneous administration should not be greater than that of a first-in-human phase I study as long as the protocol is developed with strict vigilance to detect early possible side effects from their potential interactions. Research on cancer therapy should go beyond the prevailing paradigm targeted therapy.

15.
Stat Med ; 32(5): 719-38, 2013 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-22855368

RESUMO

When comparing two treatment groups in a time-to-event analysis, it is common to use a composite event consisting of two or more distinct outcomes. The goal of this paper is to develop a statistical methodology to derive efficiency guidelines for deciding whether to expand a study primary endpoint from E1 (for example, non-fatal myocardial infarction and cardiovascular death) to the composite of E1 and E2 (for example, non-fatal myocardial infarction, cardiovascular death or revascularisation). We investigate this problem by considering the asymptotic relative efficiency of a log-rank test for comparing treatment groups with respect to a primary relevant endpoint E1 versus the composite primary endpoint, say E, of E1 and E2, where E2 is some additional endpoint.


Assuntos
Bioestatística/métodos , Determinação de Ponto Final/estatística & dados numéricos , Ensaios Clínicos Controlados Aleatórios como Assunto/estatística & dados numéricos , Vacinas contra a AIDS/administração & dosagem , Síndrome Coronariana Aguda/complicações , Síndrome Coronariana Aguda/tratamento farmacológico , Síndrome Coronariana Aguda/mortalidade , Fármacos Anti-HIV/administração & dosagem , Anticolesterolemiantes/uso terapêutico , Infecções por HIV/tratamento farmacológico , Infecções por HIV/imunologia , Humanos , Probucol/análogos & derivados , Probucol/uso terapêutico
16.
J Appl Toxicol ; 33(9): 906-14, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22729568

RESUMO

Lung cancer is the most common cancer in the world. The main cause of lung cancer is cigarette smoke; however, other important genetic and environmental risk factors play a significant role in the development of lung cancer. Among these factors, occupational and accidental exposure to polychlorinated biphenyls (PCBs) has been associated with an increased risk in lung cancer, suggesting that PCBs could be potent carcinogens. The aim of the present study was to investigate the association between PCB exposure levels, CYP1A1 polymorphisms and the risk of lung cancer. This study enrolled newly diagnosed lung cancer patients. Environmental and occupational information related to the patients studied was collected. Blood samples were taken for the measurement of serum levels of 20 PCB congeners and for CYP1A1 polymorphism analysis. The serum levels of two PCB congeners with potential estrogenic activity were higher in lung cancer patients. The risk of lung cancer was found to correlate with age, gender, smoking history and with agricultural workers, as well as with congener 18. No differences were found in the frequency of CYP1A1 polymorphisms. Furthermore, we did not find a correlation between CYP1A1 polymorphisms and PCB serum levels. The high levels of PCB with estrogenic activity found in our cases, could promote lung cancer inducing cell proliferation in non-neoplastic and neoplastic lung cells via ERß; inducing the formation of DNA adducts, producing oxidative stress with the subsequent DNA damage and increasing the endogenous catechol levels by catechol-O-methyl transferase (COMT) inhibition.


Assuntos
Carcinógenos/toxicidade , Neoplasias Pulmonares/sangue , Exposição Ocupacional/análise , Bifenilos Policlorados/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Carcinógenos/administração & dosagem , Estudos de Casos e Controles , Catecol O-Metiltransferase/metabolismo , Inibidores de Catecol O-Metiltransferase , Catecóis/metabolismo , Proliferação de Células/efeitos dos fármacos , Citocromo P-450 CYP1A1/sangue , Citocromo P-450 CYP1A1/genética , Dano ao DNA/efeitos dos fármacos , Feminino , Genótipo , Humanos , Estilo de Vida , Pulmão/citologia , Pulmão/efeitos dos fármacos , Pulmão/patologia , Neoplasias Pulmonares/induzido quimicamente , Masculino , Pessoa de Meia-Idade , Exposição Ocupacional/efeitos adversos , Razão de Chances , Estresse Oxidativo/efeitos dos fármacos , Bifenilos Policlorados/efeitos adversos , Polimorfismo Genético , Fatores de Risco , Fatores Socioeconômicos , Inquéritos e Questionários , Adulto Jovem
17.
Front Pharmacol ; 14: 1287505, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38026933

RESUMO

One of the primary diseases that cause death worldwide is cancer. Cancer cells can be intrinsically resistant or acquire resistance to therapies and drugs used for cancer treatment through multiple mechanisms of action that favor cell survival and proliferation, becoming one of the leading causes of treatment failure against cancer. A promising strategy to overcome chemoresistance and radioresistance is the co-administration of anticancer agents and natural compounds with anticancer properties, such as the polyphenolic compound resveratrol (RSV). RSV has been reported to be able to sensitize cancer cells to chemotherapeutic agents and radiotherapy, promoting cancer cell death. This review describes the reported molecular mechanisms by which RSV sensitizes tumor cells to radiotherapy and chemotherapy treatment.

18.
Microorganisms ; 11(2)2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36838225

RESUMO

The interaction among plants, insects, and microbes (PIM) is a determinant factor for the assembly and functioning of natural and anthropic ecosystems. In agroecosystems, the relationships among PIM are based on the interacting taxa, environmental conditions, and agricultural management, including genetically modified (GM) organisms. Although evidence for the unintended effects of GM plants on non-target insects is increasingly robust, our knowledge remains limited regarding their impact on gut microbes and their repercussions on the host's ecology, especially in the wild. In this study, we compared the gut microbial community of Dysdercus concinnus bugs collected on wild cotton (Gossypium hirsutum), with and without insecticidal transgenes (cry1ab/ac), in its center of origin and diversity. By sequencing the V4-V5 region of 16S rRNA, we show differences in the diversity, structure, and topology of D. concinnus gut microbial interactions between specimens foraging cotton plants with and without transgenes. Identifying unintended residual effects of genetic engineering in natural ecosystems will provide first-line knowledge for informed decision-making to manage genetic, ecological, and evolutionary resources. Thus, determining which organisms interact with GM plants and how is the first step toward conserving natural ecosystems with evidence of transgenic introgression.

19.
Clin Drug Investig ; 43(4): 227-239, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36884210

RESUMO

Therapeutic repurposing emerged as an alternative to the traditional drug discovery and development model (DDD) of new molecular entities (NMEs). It was anticipated that by being faster, safer, and cheaper, the development would result in lower-cost drugs. As defined in this work, a repurposed cancer drug is one approved by a health regulatory authority against a non-cancer indication that then gains new approval for cancer. With this definition, only three drugs are repurposed for cancer: Bacillus Calmette-Guerin (BCG) vaccine (superficial bladder cancer, thalidomide [multiple myeloma], and propranolol [infantile hemangioma]). Each of these has a different history regarding price and affordability, and it is not yet possible to generalize the impact of drug repurposing on the final price to the patient. However, the development, including the price, does not differ significantly from an NME. For the end consumer, the product's price is unrelated to whether it followed the classical development or repurposing. Economic constraints for clinical development, and drug prescription biases for repurposing drugs, are barriers yet to be overcome. The affordability of cancer drugs is a complex issue that varies from country to country. Many alternatives for having affordable drugs have been put forward, however these measures have thus far failed and are, at best, palliative. There are no immediate solutions to the problem of access to cancer drugs. It is necessary to critically analyze the impact of the current drug development model and be creative in implementing new models that genuinely benefit society.


Assuntos
Antineoplásicos , Neoplasias da Bexiga Urinária , Humanos , Reposicionamento de Medicamentos , Motivação , Antineoplásicos/uso terapêutico , Neoplasias da Bexiga Urinária/tratamento farmacológico , Vacina BCG/uso terapêutico
20.
Curr Med Chem ; 2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37287286

RESUMO

BACKGROUND: Prostate cancer is the most frequently diagnosed malignancy in 112 countries and is the leading cause of death in eighteen. In addition to continuing research on prevention and early diagnosis, improving treatments and making them more affordable is imperative. In this sense, the therapeutic repurposing of low-cost and widely available drugs could reduce global mortality from this disease. The malignant metabolic phenotype is becoming increasingly important due to its therapeutic implications. Cancer generally is characterized by hyperactivation of glycolysis, glutaminolysis, and fatty acid synthesis. However, prostate cancer is particularly lipidic; it exhibits increased activity in the pathways for synthesizing fatty acids, cholesterol, and fatty acid oxidation (FAO). OBJECTIVE: Based on a literature review, we propose the PaSTe regimen (Pantoprazole, Simvastatin, Trimetazidine) as a metabolic therapy for prostate cancer. Pantoprazole and simvastatin inhibit the enzymes fatty acid synthase (FASN) and 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR), therefore, blocking the synthesis of fatty acids and cholesterol, respectively. In contrast, trimetazidine inhibits the enzyme 3-b-Ketoacyl-CoA thiolase (3-KAT), an enzyme that catalyzes the oxidation of fatty acids (FAO). It is known that the pharmacological or genetic depletion of any of these enzymes has antitumor effects in prostatic cancer. RESULTS: Based on this information, we hypothesize that the PaSTe regimen will have increased antitumor effects and may impede the metabolic reprogramming shift. Existing knowledge shows that enzyme inhibition occurs at molar concentrations achieved in plasma at standard doses of these drugs. CONCLUSION: We conclude that this regimen deserves to be preclinically evaluated because of its clinical potential for the treatment of prostate cancer.

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