Introduction: The lung cancer continues to be the primary cause of cancer-related deaths, despite significant advancements in treatment through the introduction of immunological checkpoint inhibitors (ICI). These inhibitors, initially used as monotherapy, are now employed in combined therapies, resulting in improved survival rates. The ICI function by restoring T-cell activity to target tumor cells, but may lead to undesirable immune-related adverse events (irAE), necessitating careful management.
View Article and Find Full Text PDFBackground: Despite advances in radiation techniques, radiation cystitis (RC) remains a significant cause of morbidity from pelvic radiotherapy, which may affect patients' quality of life (QoL). The pathophysiology of RC is not well understood, which limits the development of effective treatments.
Objective: The Radiotoxicity Bladder Biomarkers study aims to investigate the correlation between blood and urinary biomarkers and the intensity of acute RC symptoms and QoL in patients undergoing localized prostate cancer radiotherapy.
Research Aim And Purpose: The benefits of Electronic Patient -Reported Outcomes (e-PRO) for telemonitoring are well established, allowing early detection of illnesses and continuous monitoring of patients. The primary objective of the PROTECTY study was to assess the compliance with patient use of the telemonitoring platform Cureety. An exploratory objective was to assess if the first-month health status is a prognostic factor of progression free-survival (PFS) and overall survival (OS) for prostate cancer patient.
View Article and Find Full Text PDFBackground: Despite improvements in radiation techniques, pelvic radiotherapy is responsible for acute and delayed bladder adverse events, defined as radiation cystitis. The initial symptoms of bladder injury secondary to pelvic irradiation are likely to occur during treatment or within 3 months of radiotherapy in approximately 50% of irradiated patients, and have a significant impact on their quality of life. The pathophysiology of radiation cystitis is not well understood, particularly because of the risk of complications associated with access to bladder tissue after irradiation, which limits our ability to study this process and develop treatments.
View Article and Find Full Text PDFRadiation cystitis (RC) results from chronic inflammation, fibrosis, and vascular damage. The urinary symptoms it causes have a serious impact on patients' quality of life. Despite the improvement in irradiation techniques, the incidence of radiation cystitis remains stable over time, and the therapeutic possibilities remain limited.
View Article and Find Full Text PDFWhile telemedicine has been shown to improve the quality of care for cancer patients, it remains underused for older patients (OP), partly due to the assumption that OPs are unabled or unwilling to use digital tools. However, more than 50% of new cancers are diagnosed in people over 70. The ConnectElderlyPatientToDoctor study aimed to evaluate the OP compliance with the use of the digital telemonitoring platform Cureety in oncology.
View Article and Find Full Text PDFBackground: Telemedicine is currently being adopted for the management of patients in routine care. However, its use remains limited in the context of clinical trials.
Objective: This study aimed to demonstrate the feasibility of telemonitoring and patient-reported outcomes collection in the context of clinical trials.
The C-termini of G protein-coupled receptors (GPCRs) interact with specific kinases and arrestins in an agonist-dependent manner suggesting that conformational changes induced by ligand binding within the transmembrane domains are transmitted to the C-terminus. Förster resonance energy transfer (FRET) can be used to monitor changes in distance between two protein domains if each site can be specifically and efficiently labeled with a donor or acceptor fluorophore. In order to probe GPCR conformational changes, we have developed a FRET technique that uses site-specific donor and acceptor fluorophores introduced by two orthogonal labeling chemistries.
View Article and Find Full Text PDFG protein-coupled receptors (GPCRs) constitute the largest family of signaling proteins in mammals, mediating responses to hormones, neurotransmitters, and senses of sight, smell and taste. Mechanistic insight into GPCR signal transduction is limited by a paucity of high-resolution structural information. We describe the generation of a monoclonal antibody that recognizes the third intracellular loop (IL3) of the native human beta(2) adrenergic (beta(2)AR) receptor; this antibody was critical for acquiring diffraction-quality crystals.
View Article and Find Full Text PDFChaperonins are allosteric double-ring ATPases that mediate cellular protein folding. ATP binding and hydrolysis control opening and closing of the central chaperonin chamber, which transiently provides a protected environment for protein folding. During evolution, two strategies to close the chaperonin chamber have emerged.
View Article and Find Full Text PDFG protein-coupled receptors (GPCRs) regulate a wide variety of physiological functions in response to structurally diverse ligands ranging from cations and small organic molecules to peptides and glycoproteins. For many GPCRs, structurally related ligands can have diverse efficacy profiles. To investigate the process of ligand binding and activation, we used fluorescence spectroscopy to study the ability of ligands having different efficacies to induce a specific conformational change in the human beta2-adrenoceptor (beta2-AR).
View Article and Find Full Text PDFMolecular chaperones assist the folding of newly translated and stress-denatured proteins. In prokaryotes, overlapping sets of chaperones mediate both processes. In contrast, we find that eukaryotes evolved distinct chaperone networks to carry out these functions.
View Article and Find Full Text PDFThe beta2 adrenoreceptor (beta2AR) is a prototypical G protein-coupled receptor (GPCR) activated by catecholamines. Agonist activation of GPCRs leads to sequential interactions with heterotrimeric G proteins, which activate cellular signaling cascades, and with GPCR kinases and arrestins, which attenuate GPCR-mediated signaling. We used fluorescence spectroscopy to monitor catecholamine-induced conformational changes in purified beta2AR.
View Article and Find Full Text PDFTrends Endocrinol Metab
October 2002
In the past decade, the concept of constitutive activity has profoundly modified our understanding of G protein-coupled-receptors (GPCRs). Here, we review the contribution of constitutively active mutants (CAMs) to our understanding of three aspects of GPCR physiopathology: (1) GPCR activation is a complex mechanism involving both the release of inactive state conformational constraints, mimicked by most CAMs, and the creation of new interactions that stabilize the active state and are mimicked by a restricted set of CAMs; (2) GPCR phosphorylation, internalization and desensitization processes are activated by receptor conformations, which partly overlap those activating G protein; (3) natural CAMs, mostly affecting GPCRs of the endocrine system, are found in several hereditary and acquired diseases, including cancers. One major remaining question is how CAMs recapitulate the different structural modifications of the agonist-induced active conformation(s) of the wild-type receptor.
View Article and Find Full Text PDFWe investigated the angiogenic properties of endothelin-1 (ET-1) using a novel experimental approach involving the constant production and release of ET-1, which was achieved by grafting stably transfected Chinese hamster ovary (CHO) (CHO-ET-1) cell aggregates onto the chorioallantoic membrane (CAM) ectoderm. Macroscopic observation showed that CHO-ET-1 cell aggregates formed highly vascularized nodules surrounded by radially rearranged vessels, with a strong angiogenic response. 5-Bromo-2'-deoxy-uridine (BrdU) studies showed an increase in endothelial cell proliferation in the CAM vasculature around CHO-ET-1 nodules.
View Article and Find Full Text PDFAs constitutively active mutants (CAMs) mimic an active conformation, they can be used to characterize the process of G protein-coupled receptor activation. Here, we used CAMs to study the link between activation and internalization of the angiotensin II AT(1A) receptor. The cellular localization of fluorescently tagged N111A, I245T, and L305Q mutants was determined by confocal microscopy.
View Article and Find Full Text PDFThe angiotensin II (Ang II) AT(1A) receptor was tagged at its C terminus with the enhanced green fluorescent protein (EGFP), and the corresponding chimeric cDNA was expressed in HEK-293 cells. This tagged receptor presents wild-type pharmacological and signaling properties and can be immunodetected by Western blotting and immunoprecipitation using EGFP antibodies. Therefore, this EGFP-tagged AT(1A) receptor is the perfect tool for analyzing in parallel the subcellular distributions of the receptor and its interacting G protein and their trafficking using confocal microscopy.
View Article and Find Full Text PDFThe constitutive activation of G-protein-coupled receptors is a major new approach to investigating their physiopathology and pharmacology. A large number of spontaneous and site-directed mutations resulting in constitutive activity have been identified, but systematic mapping of the amino acids involved for a given receptor would be extremely useful for complete elucidation of the molecular mechanisms underlying its activation. We carried out such mapping for the angiotensin II type 1A (AT(1A)) receptor by screening a randomly mutated cDNA library after expressing the mutated clones in eukaryotic cells.
View Article and Find Full Text PDFThe angiotensin II (AngII) AT1 receptor is a seven-transmembrane domain receptor coupled to a Gq/11 protein and phospholipase C, but also to other G proteins and to several tyrosine kinase pathways. These signaling pathways transduce inside the cells the classical actions of AngII (vasoconstriction, aldosterone secretion, etc.), but also the mitogenic action of this vasoactive peptide.
View Article and Find Full Text PDFEndothelin-converting-enzyme-1 (ECE-1) belongs to the family of zinc metallopeptidases and is responsible for generating endothelin (ET) peptides from their inactive precursors the big endothelins (bigET). The enzyme is a type II integral membrane protein consisting of a short amino-terminal cytosolic domain of 56 amino acids, a single transmembrane domain and a large putative extracellular domain containing the catalytic site. Recombinant and native ECE-1 are expressed as a dimer.
View Article and Find Full Text PDFEndothelin-1 (ET-1) is formed from its precursor preproET-1 via the cleavage of the intermediate bigET-1 by endothelin-converting enzyme (ECE-1). However, the subcellular site at which this step occurs is not clear: It could occur intravesicularly along the secretory pathway or bigET-1 might be released and processed extracellularly. To address this point, we have developed an integrated autocrine system that uses a recombinant Chinese hamster ovary (CHO) luciferase reporter cell line that permanently expresses the human ET(A) receptor.
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