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Frontiers in Neurology 2020Tau protein, a neuronal microtubule-associated protein, becomes hyperphosphorylated in several neurodegenerative diseases called tauopathies. Hyperphosphorylation of tau...
Similarities and Differences in the Pattern of Tau Hyperphosphorylation in Physiological and Pathological Conditions: Impacts on the Elaboration of Therapies to Prevent Tau Pathology.
Tau protein, a neuronal microtubule-associated protein, becomes hyperphosphorylated in several neurodegenerative diseases called tauopathies. Hyperphosphorylation of tau is correlated to its redistribution from the axon to the somato-dendritic compartment at early stages of tauopathies. Interestingly, tau hyperphosphorylation begins in different regions of the brain in each tauopathy. In some regions, both neurons and glial cells develop tau hyperphosphorylation. Tau hyperphosphorylation is also observed in physiological conditions such as hibernation and brain development. In the first section of present article, we will review the spatiotemporal and cellular distribution of hyperphosphorylated tau in the most frequent tauopathies. In the second section, we will compare the pattern of tau hyperphosphorylation in physiological and pathological conditions and discuss the sites that could play a pivotal role in the conversion of non-toxic to toxic forms of hyperphosphorylated tau. Furthermore, we will discuss the role of hyperphosphorylated tau in physiological and pathological conditions and the fact that tau hyperphosphorylation is reversible in physiological conditions but not in a pathological ones. In the third section, we will speculate how the differences and similarities between hyperphosphorylated tau in physiological and pathological conditions could impact the elaboration of therapies to prevent tau pathology. In the fourth section, the different therapeutic approaches using tau as a direct or indirect therapeutic target will be presented.
PubMed: 33488502
DOI: 10.3389/fneur.2020.607680 -
European Journal of Human Genetics :... Jun 2021Since a substantial difference in the prevalence of genetic causes of rod-cone dystrophy (RCD) was found among different populations, we conducted a systematic review of...
Since a substantial difference in the prevalence of genetic causes of rod-cone dystrophy (RCD) was found among different populations, we conducted a systematic review of the genetic findings associated with RCD in Arab countries. Of the 816 articles retrieved from PubMed, 31 studies conducted on 407 participants from 11 countries were reviewed. Next-generation sequencing (NGS) was the most commonly used technique (68%). Autosomal recessive pattern was the most common pattern of inheritance (97%) and half of the known genes associated with RCD (32/63) were identified. In the Kingdom of Saudi Arabia, in addition to RP1 (20%) and TULP1 (20%), gene defects in EYS (8%) and CRB1 (7%) were also prevalently mutated. In North Africa, the main gene defects were in MERTK (18%) and RLBP1 (18%). Considering all countries, RP1 and TULP1 remained the most prevalently mutated. Variants in TULP1, RP1, EYS, MERTK, and RLBP1 were the most prevalent, possibly because of founder effects. On the other hand, only ten Individuals were found to have dominant or X-linked RCD. This is the first time a catalog of RCD genetic variations has been established in subjects from the Arabi countries. Although the last decade has seen significant interest, expertise, and an increase in RCD scientific publication, much work needs to be conducted.
Topics: Carrier Proteins; Cone-Rod Dystrophies; Eye Proteins; Female; Gene Frequency; Genetic Heterogeneity; Genetic Testing; Humans; Male; Microtubule-Associated Proteins; Middle East; Mutation; c-Mer Tyrosine Kinase
PubMed: 33188265
DOI: 10.1038/s41431-020-00754-0 -
Expert Review of Anticancer Therapy Nov 2018Cisplatin-based chemotherapy administered concomitantly to thoracic radiotherapy is the treatment recommended by the European guidelines for fit patients with...
Cisplatin-based chemotherapy administered concomitantly to thoracic radiotherapy is the treatment recommended by the European guidelines for fit patients with unresectable stage III non-small cell lung cancer (NSCLC). Cisplatin may be combined with etoposide, vinorelbine or other vinca alkaloids, which act also as radiation sensitizers. Initially administered intravenously, vinorelbine is also available as oral formulation and is the only orally available microtubule-targeting agent. In addition, the oral formulation avoids the risk of extravasation and phlebitis. Areas covered: A literature search has been performed for articles reporting phase II-III trials aimed to evaluate efficacy and safety of oral vinorelbine-based chemoradiotherapy in unresectable locally advanced NSCLC. Expert commentary: In a series of trials with various protocols published from 2008 to 2018, mostly phase II studies, oral vinorelbine demonstrated a significant activity in concomitant chemoradiotherapy for unresectable locally advanced NSCLC typically as part of combination schedules with cisplatin. Main toxicities were hematologic (neutropenia and anemia); non-hematological toxicities included esophagitis and gastro-duodenal adverse events. Large prospective phase III trials are needed to confirm the role of vinorelbine-based chemotherapy associated to thoracic radiotherapy in unresectable stage III NSCLC and more particularly trials with metronomic oral vinorelbine.
Topics: Administration, Oral; Antineoplastic Combined Chemotherapy Protocols; Carcinoma, Non-Small-Cell Lung; Chemoradiotherapy; Cisplatin; Humans; Lung Neoplasms; Neoplasm Staging; Vinorelbine
PubMed: 30173589
DOI: 10.1080/14737140.2018.1518714 -
OncoTargets and Therapy 2015Ovarian cancer is the most lethal gynecologic malignancy; consequently, there is a need for effective therapies. Epothilones are microtubule-stabilizing agents that...
Ovarian cancer is the most lethal gynecologic malignancy; consequently, there is a need for effective therapies. Epothilones are microtubule-stabilizing agents that inhibit cell growth. Currently, patupilone and its four synthetic derivatives ixabepilone, BMS-310705, sagopilone, 20-desmethyl-20-methylsulfanyl epothilone B and epothilone D, as well as its derivative KOS-1584, are under clinical evaluation. This is the first systematic review conducted in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines that synthesizes all available data emerging from trials and evaluates the efficacy and safety of epothilones in epithelial ovarian, primary fallopian tube, and primary peritoneal cancer. Despite the fact that epothilones have proven active in taxane-resistant settings in preclinical models, it is not yet clear from Phase II/III studies reviewed here that their clinical activity is superior to that of taxanes. Nevertheless, responses to epothilones have been observed in platinum-refractory/resistant ovarian cancer patients. Moreover, despite the shared mechanism of action of epothilones, their clinical profile seems clearly different, with diarrhea being the most common dose-limiting toxicity encountered with patupilone, whereas neutropenia and sensory neuropathy are the most common toxic effects observed with the other epothilones. In any case, randomized trials comparing epothilones with standard treatments seem warranted to define further the role of these agents, whereas biomarker analysis might further optimize patient selection.
PubMed: 26316786
DOI: 10.2147/OTT.S77342