Pancreatic cancer cells with mutant KRAS require strong basal autophagy for viability and growth. Here, we observed that some processes that allow the maintenance of basal autophagy in pancreatic cancer cells are controlled by protein methylation. Thus, by maintaining the methylation status of proteins such as PP2A and MRAS, these cells can sustain their autophagic activity.
View Article and Find Full Text PDFThe anatomical location of cutaneous melanoma is a relevant independent prognostic factor in melanoma. The aim of the study is to know the prognosis of lower limb cutaneous melanoma related to their location within the limb, regardless of the histological type, and if there are any other influencing variables. A real-world data observational study was developed.
View Article and Find Full Text PDFBackground: Primary prevention strategies for asthma are lacking. Its inception probably starts in utero and/or during the early postnatal period as the developmental origins of health and disease (DOHaD) paradigm suggests.
Objectives: The main objective of Nutrition in Early Life and Asthma (NELA) cohort study is to unravel whether the following factors contribute causally to the developmental origins of asthma: (1) maternal obesity/adiposity and foetal growth; (2) maternal and child nutrition; (3) outdoor air pollution; (4) endocrine disruptors; and (5) maternal psychological stress.
Background: The application of immune-based therapies has revolutionized cancer treatment. Yet how the immune system responds to phenotypically heterogeneous populations within tumors is poorly understood. In melanoma, one of the major determinants of phenotypic identity is the lineage survival oncogene MITF that integrates diverse microenvironmental cues to coordinate melanoma survival, senescence bypass, differentiation, proliferation, invasion, metabolism and DNA damage repair.
View Article and Find Full Text PDFHypoxia-inducible factor (HIF)-1α is constitutively expressed in melanoma cells under normoxic conditions and its elevated expression correlates with the aggressiveness of melanoma tumors. Here, we used acriflavine, a potent inhibitor of HIF-1α dimerization, as a tool to investigate whether HIF-1α-regulated pathways contribute to the growth of melanoma cells under normoxia. We observed that acriflavine differentially modulated HIF-1α-regulated targets in melanoma under normoxic conditions, although acriflavine treatment resulted in over-expression of vascular endothelial growth factor (VEGF), its action clearly downregulated the expression of pyruvate dehydrogenase kinase 1 (PDK1), a well-known target of HIF-1α.
View Article and Find Full Text PDFCancers (Basel)
September 2020
Background: some types of cancer have been associated with the presence of single nucleotide polymorphisms (SNPs) of some genes that encode enzymes: glutathione-S transferase (GST), whose alteration leads to loss of function and a lower capacity to eliminate toxic GSTM1 and GSTT1 null genotypes; SNPs causing loss of function of CYP1A1 or CYP1A1-2 cytochrome P450 enzymes related with a lower capacity to deactivate hydrocarbons related to smoking, which involves a higher risk of developing some smoking-dependent cancers including larynx cancer.
Objective: to compare the presence of null SNPs in genes GSTM1, GSTT1, and CYP1A1 rs 4646903 T>C, and CYP1A1-2 RS1048943 A>G in patients with hypopharyngeal and larynx cancer with a healthy control group.
Materials And Method: The study included a total of 80 patients with hypopharyngeal and laryngeal cancer and 23 healthy subjects.
The therapeutic effect of irradiation is thought to come from DNA damage that affects rapidly proliferating cancer cells; however, resistant cells rapidly initiate mechanisms to repair such damage. While DNA repair mechanisms responsible for cancer cell survival following DNA damage are understood, less is known about the epigenetic mechanisms resulting in resistance to radiotherapy. Although changes in DNA methylation are related to mechanisms of long-term resistance, it is more likely that the methylation state of a series of proteins could be responsible for the first-line of defense of cancer cells against irradiation.
View Article and Find Full Text PDFDilated cardiomyopathy (DCM) belongs to the most frequent forms of cardiomyopathy mainly characterized by cardiac dilatation and reduced systolic function. Although most cases of DCM are classified as sporadic, 20-30% of cases show a heritable pattern. Familial forms of DCM are genetically heterogeneous, and mutations in several genes have been identified that most commonly play a role in cytoskeleton and sarcomere-associated processes.
View Article and Find Full Text PDFBackground: Bladder cancer (BC) is highly immunogenic. Bacillus Calmette-Guérin (BCG) immunotherapy offers the best results in non-muscle-invasive BC (NMIBC). Natural killer cells (NKcs) play decisive roles in BCG-mediated immune response and in general cancer immune-surveillance.
View Article and Find Full Text PDFIn this study, the influence of several factors such as breed, sex, and production stage over the normal range values of salivary biomarkers of health status was evaluated in pigs. A total of 409 pigs of 2 different breeds (conventional Large White × Duroc and Iberian pigs) were included in the study. Animals were divided into different groups according to their sex (male or female) and the stage of the production cycle they were in (post-weaning, nursery, fattening, and finishing).
View Article and Find Full Text PDFThe quantification of adenosine deaminase (ADA) in porcine saliva samples has been analyzed for its use as a marker of disease. First, an analytical validation of the enzymatic assay used for ADA measurements was performed. Afterwards, saliva samples were collected from 50 healthy animals and 64 animals with different symptoms of disease, which were divided into local inflammation, gastrointestinal disorder, respiratory disorder and growth retardation.
View Article and Find Full Text PDFPurpose: The higher sensitivity of new diagnostic tools makes it easier to detect relapse in asymptomatic stages when classic procedures of lymph node biopsies are difficult to perform. The aim of this article is to describe the combination of gamma probe and 18F-FDG positron emission tomography-computed tomography (PET-CT) images in combination with sentinel lymph node biopsy technique for detection of nonpalpable lymph nodes.
Methods: After a dose of 18F-FDG was administered and PET-CT images that showed the location of suspected pathologic lymph nodes were obtained, transcutaneous localization of the lymph nodes with the highest captation of the tracer was done.
The observation of acetylcholinesterase (AChE) type H (AChE), which is the predominant AChE variant in visceral organs and immune cells, in lipid rafts of muscle supports functional reasons for the raft targeting of glypiated AChE The search for these reasons revealed that liver AChE activity is mostly confined to rafts and that the liver is able to make N-extended AChE variants and target them to rafts. These results prompted us to test whether AChE and muscarinic receptors existed in the same raft. Isolation of flotillin-2-rich raft fractions by their buoyancy in sucrose gradients, followed by immunoadsorption and matrix-assisted laser desorption ionization-time of flight-mass spectrometry application, gave the following results: 1) most hepatic AChE activity emanates from AChE-H mRNA, and its product, glypiated AChE, accumulates in rafts; 2) N-extended N-AChE readthrough variant, nonglypiated N-AChE, and N-AChE tailed variant were all identified in liver rafts; and 3) M3 AChRs were observed in rafts, and coprecipitation of raft-confined N-AChE and M3 receptors by using anti-M3 antibodies showed that enzyme and receptor reside in the same raft unit.
View Article and Find Full Text PDFPrevious reports have demonstrated that a non-neuronal cholinergic system is expressed aberrantly in airways. A proliferative effect is exerted directly by cholinergic agonists through the activation of nicotinic and muscarinic receptors. In cancer, particularly those related with smoking, the mechanism through which tumour cells respond to aberrantly activated cholinergic signalling is a key question.
View Article and Find Full Text PDFBackground: In airways, a proliferative effect is played directly by cholinergic agonists through nicotinic and muscarinic receptors activation. How tumors respond to aberrantly activated cholinergic signalling is a key question in smoking-related cancer. This research was addressed to explore a possible link of cholinergic signalling changes with cancer biology.
View Article and Find Full Text PDFWhile the functional implications of AChE-T, PRiMA and ColQ have been firmly established, those of glypiated AChE remain uncertain. Insights into the physiological meaning of glycosylphosphatidylinositol (GPI)-linked AChE-H were gained by comparing nervous and non-nervous tissues for the amount of AChE mRNA variants they contained. PCR showed that AChE-T mRNA prevailed in the mouse brain, spinal cord, sciatic nerve and muscle, and AChE-H mRNA in the bone marrow and thymus, as well as in the human gut.
View Article and Find Full Text PDFHuman melanoma is a significant clinical problem. As most melanoma patients relapse with lethal drug-resistant disease, understanding and preventing mechanism(s) of resistance is one of the highest priorities to improve melanoma therapy. Melanosomal sequestration and the cellular exportation of cytotoxic drugs have been proposed to be important melanoma-specific mechanisms that contribute to multidrug resistance in melanoma.
View Article and Find Full Text PDFTherapeutic resistance in melanoma and other cancers arises via irreversible genetic, and dynamic phenotypic, heterogeneity. Here, we use directed phenotype switching in melanoma to sensitize melanoma cells to lineage-specific therapy. We show that methotrexate (MTX) induces microphthalmia-associated transcription factor (MITF) expression to inhibit invasiveness and promote differentiation-associated expression of the melanocyte-specific Tyrosinase gene.
View Article and Find Full Text PDFBackground: Tumour suppressor genes are often transcriptionally silenced by promoter hypermethylation, and recent research has implicated alterations in chromatin structure as the mechanistic basis for this repression. In addition to DNA methylation, other epigenetic post-translational modifications that modulate the stability and binding of specific transcription factors to gene promoters have emerged as important mechanisms for controlling gene expression. The aim of this study was to analyse the implications of these mechanisms and their molecular connections in the reactivation of RASSF1A in breast cancer.
View Article and Find Full Text PDFMelanoma, the most aggressive form of skin cancer, is notoriously resistant to all current modalities of cancer therapy, including to the drug methotrexate. Melanosomal sequestration and cellular exportation of methotrexate have been proposed to be important melanoma-specific mechanisms that contribute to the resistance of melanoma to methotrexate. In addition, other mechanisms of resistance that are present in most epithelial cancer cells are also operative in melanoma.
View Article and Find Full Text PDFPresenilins (PS1 and PS2) and the amyloid-β precursor protein (AβPP) are the only known proteins as causing monogenic Alzheimer's disease. AβPP is not the unique substrate of the γ-secretase complex. Presenilins are also implicated in the processing of Notch, an important developmental protein, which is thought to compete directly with AβPP for cleavage by γ-secretase.
View Article and Find Full Text PDFDespite bioavailability issues, tea catechins have emerged as promising chemopreventive agents because of their efficacy in various animal models. We synthesized two catechin-derived compounds, 3-O-(3,4,5-trimethoxybenzoyl)-(-)-catechin (TMCG) and 3-O-(3,4,5-trimethoxybenzoyl)-(-)-epicatechin (TMECG), in an attempt to improve the stability and cellular absorption of tea polyphenols. The antiproliferative and pro-apoptotic activities of both compounds were analyzed with various cancer cell systems, and TMCG, which was easily synthesized in excellent yield, was more active than TMECG in both melanoma and non-melanoma cell lines.
View Article and Find Full Text PDFDespite the aberrant expression of cholinesterases in tumours, the question of their possible contribution to tumorigenesis remains unsolved. The identification in kidney of a cholinergic system has paved the way to functional studies, but details on renal cholinesterases are still lacking. To fill the gap and to determine whether cholinesterases are abnormally expressed in renal tumours, paired pieces of normal kidney and renal cell carcinomas (RCCs) were compared for cholinesterase activity and mRNA levels.
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