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1.
Mol Cell ; 84(4): 760-775.e7, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38215751

RESUMO

Apart from the canonical serotonin (5-hydroxytryptamine [5-HT])-receptor signaling transduction pattern, 5-HT-involved post-translational serotonylation has recently been noted. Here, we report a glyceraldehyde-3-phosphate dehydrogenase (GAPDH) serotonylation system that promotes the glycolytic metabolism and antitumor immune activity of CD8+ T cells. Tissue transglutaminase 2 (TGM2) transfers 5-HT to GAPDH glutamine 262 and catalyzes the serotonylation reaction. Serotonylation supports the cytoplasmic localization of GAPDH, which induces a glycolytic metabolic shift in CD8+ T cells and contributes to antitumor immunity. CD8+ T cells accumulate intracellular 5-HT for serotonylation through both synthesis by tryptophan hydroxylase 1 (TPH1) and uptake from the extracellular compartment via serotonin transporter (SERT). Monoamine oxidase A (MAOA) degrades 5-HT and acts as an intrinsic negative regulator of CD8+ T cells. The adoptive transfer of 5-HT-producing TPH1-overexpressing chimeric antigen receptor T (CAR-T) cells induced a robust antitumor response. Our findings expand the known range of neuroimmune interaction patterns by providing evidence of receptor-independent serotonylation post-translational modification.


Assuntos
Linfócitos T CD8-Positivos , Serotonina , Linfócitos T CD8-Positivos/metabolismo , Serotonina/metabolismo , Serotonina/farmacologia , Processamento de Proteína Pós-Traducional , Transdução de Sinais
2.
Cell ; 166(6): 1471-1484.e18, 2016 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-27610571

RESUMO

The design of immunogens that elicit broadly reactive neutralizing antibodies (bnAbs) has been a major obstacle to HIV-1 vaccine development. One approach to assess potential immunogens is to use mice expressing precursors of human bnAbs as vaccination models. The bnAbs of the VRC01-class derive from the IGHV1-2 immunoglobulin heavy chain and neutralize a wide spectrum of HIV-1 strains via targeting the CD4 binding site of the envelope glycoprotein gp120. We now describe a mouse vaccination model that allows a germline human IGHV1-2(∗)02 segment to undergo normal V(D)J recombination and, thereby, leads to the generation of peripheral B cells that express a highly diverse repertoire of VRC01-related receptors. When sequentially immunized with modified gp120 glycoproteins designed to engage VRC01 germline and intermediate antibodies, IGHV1-2(∗)02-rearranging mice, which also express a VRC01-antibody precursor light chain, can support the affinity maturation of VRC01 precursor antibodies into HIV-neutralizing antibody lineages.


Assuntos
Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , HIV-1/imunologia , Imunização , Cadeias Pesadas de Imunoglobulinas/imunologia , Células Precursoras de Linfócitos B/imunologia , Animais , Anticorpos Monoclonais/genética , Linfócitos B/imunologia , Anticorpos Amplamente Neutralizantes , Linhagem Celular , Modelos Animais de Doenças , Regulação da Expressão Gênica/imunologia , Anticorpos Anti-HIV , Cadeias Pesadas de Imunoglobulinas/química , Cadeias Pesadas de Imunoglobulinas/genética , Concentração Inibidora 50 , Camundongos , Deleção de Sequência , Linfócitos T/imunologia
3.
Nature ; 582(7810): 124-128, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32494071

RESUMO

In most species, homologous chromosomes must recombine in order to segregate accurately during meiosis1. Because small chromosomes would be at risk of missegregation if recombination were randomly distributed, the double-strand breaks (DSBs) that initiate recombination are not located arbitrarily2. How the nonrandomness of DSB distributions is controlled is not understood, although several pathways are known to regulate the timing, location and number of DSBs. Meiotic DSBs are generated by Spo11 and accessory DSB proteins, including Rec114 and Mer2, which assemble on chromosomes3-7 and are nearly universal in eukaryotes8-11. Here we demonstrate how Saccharomyces cerevisiae integrates multiple temporally distinct pathways to regulate the binding of Rec114 and Mer2 to chromosomes, thereby controlling the duration of a DSB-competent state. The engagement of homologous chromosomes with each other regulates the dissociation of Rec114 and Mer2 later in prophase I, whereas the timing of replication and the proximity to centromeres or telomeres influence the accumulation of Rec114 and Mer2 early in prophase I. Another early mechanism enhances the binding of Rec114 and Mer2 specifically on the shortest chromosomes, and is subject to selection pressure to maintain the hyperrecombinogenic properties of these chromosomes. Thus, the karyotype of an organism and its risk of meiotic missegregation influence the shape and evolution of its recombination landscape. Our results provide a cohesive view of a multifaceted and evolutionarily constrained system that allocates DSBs to all pairs of homologous chromosomes.


Assuntos
Cromossomos Fúngicos/genética , Recombinação Homóloga , Meiose , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/genética , Centrômero/genética , Segregação de Cromossomos , Cromossomos Fúngicos/metabolismo , Quebras de DNA de Cadeia Dupla , Período de Replicação do DNA , Meiose/genética , Prófase Meiótica I/genética , Recombinases/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Telômero/genética , Fatores de Tempo
4.
Nucleic Acids Res ; 52(10): 5732-5755, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38597682

RESUMO

Expansion of a G4C2 repeat in the C9orf72 gene is associated with familial Amyotrophic Lateral Sclerosis (ALS) and Frontotemporal Dementia (FTD). To investigate the underlying mechanisms of repeat instability, which occurs both somatically and intergenerationally, we created a novel mouse model of familial ALS/FTD that harbors 96 copies of G4C2 repeats at a humanized C9orf72 locus. In mouse embryonic stem cells, we observed two modes of repeat expansion. First, we noted minor increases in repeat length per expansion event, which was dependent on a mismatch repair pathway protein Msh2. Second, we found major increases in repeat length per event when a DNA double- or single-strand break (DSB/SSB) was artificially introduced proximal to the repeats, and which was dependent on the homology-directed repair (HDR) pathway. In mice, the first mode primarily drove somatic repeat expansion. Major changes in repeat length, including expansion, were observed when SSB was introduced in one-cell embryos, or intergenerationally without DSB/SSB introduction if G4C2 repeats exceeded 400 copies, although spontaneous HDR-mediated expansion has yet to be identified. These findings provide a novel strategy to model repeat expansion in a non-human genome and offer insights into the mechanism behind C9orf72 G4C2 repeat instability.


Assuntos
Proteína C9orf72 , Expansão das Repetições de DNA , Instabilidade Genômica , Animais , Humanos , Camundongos , Esclerose Lateral Amiotrófica/genética , Proteína C9orf72/genética , Modelos Animais de Doenças , Quebras de DNA de Cadeia Dupla , Expansão das Repetições de DNA/genética , Demência Frontotemporal/genética , Técnicas de Introdução de Genes , Instabilidade Genômica/genética , Proteína 2 Homóloga a MutS/genética
5.
Mol Biol Evol ; 41(3)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38415852

RESUMO

Island organisms often evolve phenotypes divergent from their mainland counterparts, providing a useful system for studying adaptation under differential selection. In the white-winged fairywren (Malurus leucopterus), subspecies on two islands have a black nuptial plumage whereas the subspecies on the Australian mainland has a blue nuptial plumage. The black subspecies have a feather nanostructure that could in principle produce a blue structural color, suggesting a blue ancestor. An earlier study proposed independent evolution of melanism on the islands based on the history of subspecies divergence. However, the genetic basis of melanism and the origin of color differentiation in this group are still unknown. Here, we used whole-genome resequencing to investigate the genetic basis of melanism by comparing the blue and black M. leucopterus subspecies to identify highly divergent genomic regions. We identified a well-known pigmentation gene ASIP and four candidate genes that may contribute to feather nanostructure development. Contrary to the prediction of convergent evolution of island melanism, we detected signatures of a selective sweep in genomic regions containing ASIP and SCUBE2 not in the black subspecies but in the blue subspecies, which possesses many derived SNPs in these regions, suggesting that the mainland subspecies has re-evolved a blue plumage from a black ancestor. This proposed re-evolution was likely driven by a preexisting female preference. Our findings provide new insight into the evolution of plumage coloration in island versus continental populations, and, importantly, we identify candidate genes that likely play roles in the development and evolution of feather structural coloration.


Assuntos
Melanose , Passeriformes , Aves Canoras , Animais , Aves Canoras/genética , Austrália , Passeriformes/genética , Polimorfismo de Nucleotídeo Único , Plumas , Pigmentação , Cor
6.
FASEB J ; 38(10): e23705, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38805171

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive malignancies, with a notoriously dismal prognosis. As a competitive inhibitor of DNA synthesis, gemcitabine is the cornerstone drug for treating PDAC at all stages. The therapeutic effect of gemcitabine, however, is often hindered by drug resistance, and the underlying mechanisms remain largely unknown. It is unclear whether their response to chemotherapeutics is regulated by endocrine regulators, despite the association between PDAC risk and endocrine deregulation. Here, we show that prolactin receptor (PRLR) synergizes with gemcitabine in both in vitro and in vivo treatment of PDAC. Interestingly, PRLR promotes the expression of miR-4763-3p and miR-3663-5p, two novel miRNAs whose functions are unknown. Furthermore, the analysis of transcriptome sequencing data of tumors from lactating mouse models enriches the PPP pathway, a multifunctional metabolic pathway. In addition to providing energy, the PPP pathway mainly provides a variety of raw materials for anabolism. We demonstrate that two key enzymes of the pentose phosphate pathway (PPP), G6PD and TKT, are directly targeted by miR-4763-3p and miR-3663-5p. Notably, miR-4763-3p and miR-3663-5p diminish the nucleotide synthesis of the PPP pathway, thereby increasing gemcitabine sensitivity. As a result, PRLR harnesses these two miRNAs to suppress PPP and nucleotide synthesis, subsequently elevating the gemcitabine sensitivity of PDAC cells. Also, PDAC tissues and tumors from LSL-KrasG12D/+, LSL-Trp53R172H/+, and PDX1-cre (KPC) mice exhibit downregulation of PRLR. Bisulfite sequencing of PDAC tissues revealed that PRLR downregulation is due to epigenetic methylation. In this study, we show for the first time that the endocrine receptor PRLR improves the effects of gemcitabine by boosting two new miRNAs that block the PPP pathway and nucleotide synthesis by inhibiting two essential enzymes concurrently. The PRLR-miRNAs-PPP axis may serve as a possible therapeutic target to supplement chemotherapy advantages in PDAC.


Assuntos
Carcinoma Ductal Pancreático , Desoxicitidina , Gencitabina , Glucosefosfato Desidrogenase , MicroRNAs , Neoplasias Pancreáticas , Receptores da Prolactina , Animais , Feminino , Humanos , Camundongos , Antimetabólitos Antineoplásicos/farmacologia , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patologia , Linhagem Celular Tumoral , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glucosefosfato Desidrogenase/metabolismo , Glucosefosfato Desidrogenase/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Receptores da Prolactina/metabolismo , Receptores da Prolactina/genética , Camundongos Nus
7.
Neuroimage ; 291: 120588, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38537765

RESUMO

BACKGROUND: Parkinson's disease (PD) is associated with the loss of neuromelanin (NM) and increased iron in the substantia nigra (SN). Magnetization transfer contrast (MTC) is widely used for NM visualization but has limitations in brain coverage and scan time. This study aimed to develop a new approach called Proton-density Enhanced Neuromelanin Contrast in Low flip angle gradient echo (PENCIL) imaging to visualize NM in the SN. METHODS: This study included 30 PD subjects and 50 healthy controls (HCs) scanned at 3T. PENCIL and MTC images were acquired. NM volume in the SN pars compacta (SNpc), normalized image contrast (Cnorm), and contrast-to-noise ratio (CNR) were calculated. The change of NM volume in the SNpc with age was analyzed using the HC data. A group analysis compared differences between PD subjects and HCs. Receiver operating characteristic (ROC) analysis and area under the curve (AUC) calculations were used to evaluate the diagnostic performance of NM volume and CNR in the SNpc. RESULTS: PENCIL provided similar visualization and structural information of NM compared to MTC. In HCs, PENCIL showed higher NM volume in the SNpc than MTC, but this difference was not observed in PD subjects. PENCIL had higher CNR, while MTC had higher Cnorm. Both methods revealed a similar pattern of NM volume in SNpc changes with age. There were no significant differences in AUCs between NM volume in SNpc measured by PENCIL and MTC. Both methods exhibited comparable diagnostic performance in this regard. CONCLUSIONS: PENCIL imaging provided improved CNR compared to MTC and showed similar diagnostic performance for differentiating PD subjects from HCs. The major advantage is PENCIL has rapid whole-brain coverage and, when using STAGE imaging, offers a one-stop quantitative assessment of tissue properties.


Assuntos
Doença de Parkinson , Humanos , Doença de Parkinson/diagnóstico por imagem , Substância Negra/diagnóstico por imagem , Parte Compacta da Substância Negra , Imageamento por Ressonância Magnética/métodos , Melaninas
8.
J Am Chem Soc ; 146(30): 21120-21128, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39034829

RESUMO

Since the concept of "multiferroic" was first proposed in 1968, the coupling effect between different ferroic orders has attracted great interest in energy, information, and biomedical fields. However, the fully ferroelectric-fully ferroelastic effect has never been experimentally observed in hybrid perovskites, even though this effect was predicted to exist half a century ago. Realizing such cross-linking effects of polarization vectors and strain tensors has always been a huge challenge because of the complex difference in these two ferroic origins. Here, we report a multiferroic with full ferroelectricity and full ferroelasticity in two-dimensional (2D) hybrid perovskites based on ferroelectrochemistry. The dynamic molecular reorientations endow (cyclohexanemethylaminium)2PbCl4 with a desired symmetry change of 4̅2mFmm2 at a Curie temperature of 411.8 K. More strikingly, the switchable evolution of ferroelastic domains was directly observed under the control of either electric or mechanical fields, which is the first experimental observation of a fully ferroelectric-fully ferroelastic effect in hybrid perovskites. This work would provide new insights into understanding the intrinsic cross-linking mechanism between ferroelectricity and ferroelasticity toward the development of multichannel interactive microelectronic devices.

9.
J Am Chem Soc ; 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39141483

RESUMO

Ferroelectricity in metal-free perovskites (MFPs) has emerged as an academic hotspot for their lightweight, eco-friendly processability, flexibility, and degradability, with considerable progress including large spontaneous polarization, high Curie temperature, large piezoelectric response, and tailoring coercive field. However, their equivalent polarization axes as a key indicator are far from enough, although multiaxial ferroelectrics are highly preferred for performance output and application flexibility that profit from as many equivalent polarization directions as possible with easier reorientation. Here, by implementing the synergistic overlap of regulating anionic geometries (from spherical I- to octahedral [PF6]- and to tetrahedral [ClO4]- or [BF4]-) and cationic asymmetric modification, we successfully designed multiaxial MFP ferroelectrics CMDABCO-NH4-X3 (CMDABCO = N-chloromethyl-N'-diazabicyclo[2.2.2]octonium; X = [ClO4]- or [BF4]-) with the lowest P1 symmetry. More impressively, systemic characterizations indicate that they possess 24 equivalent polarization axes (Aizu notations of 432F1 and m3̅mF1, respectively)─the maximum number achievable for ferroelectrics. Benefiting from the multiaxial feature, CMDABCO-NH4-[ClO4]3 has been demonstrated to have excellent piezoelectric sensing performance in its polycrystalline sample and prepared composite device. Our study provides a feasible strategy for designing multiaxial MFP ferroelectrics and highlights their great promise for use in microelectromechanical, sensing, and body-compatible devices.

10.
J Am Chem Soc ; 146(37): 25832-25840, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39231362

RESUMO

The connectivity (valency) of building blocks for constructing 3D covalent organic frameworks (COFs) has long been limited to 4, 6, 8, and 12. Developing a higher connectivity remains a great challenge in the field of COF structural design. Herein, this work reports a hierarchical expansion strategy for making 16-connected building blocks to construct 3D COFs with sqc topology. The [16 + 2] construction achieved by condensation between a 16-connected carbazolyl dicyanobenzene-based building block (CzTPN) and linear diamino linkers (BD or Bpy) affords two 3D COFs (named CzBD COF and CzBpy COF). Furthermore, attributed to the well-organized donor-acceptor (D-A) heterojunction, the Ni chelated CzBpy COF (Ni@CzBpy COF) exhibits excellent performance for photoredox/Ni dual catalytic C(sp3)-C(sp2) cross-coupling of alkyltrifluoroborates with aryl halides, achieving a maximum 98% conversion and 94% yield for various substrates. This work developed the first case of high-connectivity COFs bearing 16-connected units, which is the highest connectivity reported until now, and achieved efficient photocatalysis applications, thus greatly enriching the possibilities of COFs.

11.
Neurobiol Dis ; 199: 106577, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38914171

RESUMO

Proper topographically organized neural connections between the thalamus and the cerebral cortex are mandatory for thalamus function. Thalamocortical (TC) fiber growth begins during the embryonic period and completes by the third trimester of gestation, so that human neonates at birth have a thalamus with a near-facsimile of adult functional parcellation. Whether congenital neocortical anomaly (e.g., lissencephaly) affects TC connection in humans is unknown. Here, via diffusion MRI fiber-tractography analysis of long-term formalin-fixed postmortem fetal brain diagnosed as lissencephaly in comparison with an age-matched normal one, we found similar topological patterns of thalamic subregions and of internal capsule parcellated by TC fibers. However, lissencephaly fetal brain showed white matter structural changes, including fewer/less organized TC fibers and optic radiations, and much less cortical plate invasion by TC fibers - particularly around the shallow central sulcus. Diffusion MRI fiber tractography of normal fetal brains at 15, 23, and 26 gestational weeks (GW) revealed dynamic volumetric change of each parcellated thalamic subregion, suggesting coupled developmental progress of the thalamus with the corresponding cortex. Moreover, from GW23 and GW26 normal fetal brains, TC endings in the cortical plate could be delineated to reflect cumulative progressive TC invasion of cortical plate. By contrast, lissencephaly brain showed a dramatic decrease in TC invasion of the cortical plate. Our study thus shows the feasibility of diffusion MRI fiber tractography in postmortem long-term formalin-fixed fetal brains to disclose the developmental progress of TC tracts coordinating with thalamic and neocortical growth both in normal and lissencephaly fetal brains at mid-gestational stage.


Assuntos
Córtex Cerebral , Imagem de Tensor de Difusão , Lisencefalia , Vias Neurais , Tálamo , Humanos , Tálamo/diagnóstico por imagem , Tálamo/patologia , Tálamo/embriologia , Córtex Cerebral/patologia , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/embriologia , Lisencefalia/patologia , Lisencefalia/diagnóstico por imagem , Vias Neurais/patologia , Vias Neurais/diagnóstico por imagem , Vias Neurais/embriologia , Imagem de Tensor de Difusão/métodos , Feto/patologia , Feto/diagnóstico por imagem , Idade Gestacional , Feminino , Masculino , Substância Branca/diagnóstico por imagem , Substância Branca/patologia , Substância Branca/embriologia , Imagem de Difusão por Ressonância Magnética/métodos
12.
Hum Mol Genet ; 31(18): 3161-3180, 2022 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-35567414

RESUMO

RTL1/PEG11, which has been associated with anxiety disorders, is a retrotransposon-derived imprinted gene in the placenta. However, imprinting patterns and functions of RTL1 in the brain have not been well-investigated. We found Rtl1 was paternally, but not maternally, expressed in brain stem, thalamus, and hypothalamus of mice, and imprinting status of RTL1 was maintained in human brain. Paternal Rtl1 knockout (Rtl1m+/p-) mice had higher neonatal death rates due to impaired suckling, and low body weights beginning on embryonic day 16.5. High paternal expression of Rtl1 was detected in the locus coeruleus (LC) and Rtl1m+/p- mice showed an increased delay in time of onset for action potentials and inward currents with decreased neuronal excitability of LC neurons. Importantly, Rtl1m+/p- mice exhibited behaviors associated with anxiety, depression, fear-related learning and memory, social dominance, and low locomotor activity. Taken together, our findings demonstrate RTL1 is imprinted in brain, mediates emotional and social behaviors, and regulates excitability in LC neurons.


Assuntos
Proteínas da Gravidez , Retroelementos , Animais , Ansiedade/genética , Transtornos de Ansiedade/genética , Feminino , Impressão Genômica , Humanos , Locus Cerúleo/metabolismo , Camundongos , Neurônios/metabolismo , Gravidez , Proteínas da Gravidez/genética , Proteínas da Gravidez/metabolismo , Comportamento Social
13.
J Clin Immunol ; 44(5): 117, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38758229

RESUMO

AIOLOS, a vital member of the IKAROS protein family, plays a significant role in lymphocyte development and function through DNA binding and protein-protein interactions. Mutations in the IKZF3 gene, which encodes AIOLOS, lead to a rare combined immunodeficiency often linked with infections and malignancy. In this study, we evaluated a 1-year-4-month-old female patient presenting with recurrent infections, diarrhea, and failure to thrive. Laboratory investigations revealed decreased T lymphocyte and immunoglobulin levels. Through whole-exome and Sanger sequencing, we discovered a de novo mutation in IKZF3 (NM_012481; exon 5 c.571G > C, p.Gly191Arg), corresponding to the third DNA-binding zinc finger region of the encoded protein AIOLOS. Notably, the patient with the AIOLOS G191R mutation showed reduced recent thymic emigrants in naïve CD4+T cells compared to healthy counterparts of the same age, while maintaining normal levels of Th1, Th2, Th17, Treg, and Tfh cells. This mutation also resulted in decreased switched memory B cells and lower CD23 and IgM expression. In vitro studies revealed that AIOLOS G191R does not impact the expression of AIOLOS but compromises its stability, DNA binding and pericentromeric targeting. Furthermore, AIOLOS G191R demonstrated a dominant-negative effect over the wild-type protein. This case represents the first reported instance of a mutation in the third DNA-binding zinc finger region of AIOLOS highlighting its pivotal role in immune cell functionality.


Assuntos
Fator de Transcrição Ikaros , Mutação , Humanos , Fator de Transcrição Ikaros/genética , Feminino , Mutação/genética , Lactente , Imunodeficiência Combinada Severa/genética , Imunodeficiência Combinada Severa/diagnóstico , Sequenciamento do Exoma , Linfócitos B/imunologia
14.
Lancet ; 401(10380): 917-927, 2023 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-36842439

RESUMO

BACKGROUND: Reirradiation in standard fractionation for locally advanced recurrent nasopharyngeal carcinoma after a previous course of high-dose radiotherapy is often associated with substantial late toxicity, negating its overall benefit. We therefore aimed to investigate the efficacy and safety of hyperfractionation compared with standard fractionation in intensity-modulated radiotherapy. METHODS: This multicentre, randomised, open-label, phase 3 trial was done in three centres in Guangzhou, China. Eligible patients were aged 18-65 years with histopathologically confirmed undifferentiated or differentiated, non-keratinising, advanced locally recurrent nasopharyngeal carcinoma. Participants were randomly assigned (1:1) to either receive hyperfractionation (65 Gy in 54 fractions, given twice daily with an interfractional time interval of at least 6 h) or standard fractionation (60 Gy in 27 fractions, given once a day). Intensity-modulated radiotherapy was used in both groups. A computer program generated the assignment sequence and randomisation was stratified by treatment centre, recurrent tumour stage (T2-T3 vs T4), and recurrent nodal stage (N0 vs N1-N2), determined at the time of randomisation. The two primary endpoints were the incidence of severe late complications defined as the incidence of grade 3 or worse late radiation-induced complications occurring 3 months after the completion of radiotherapy until the latest follow-up in the safety population, and overall survival defined as the time interval from randomisation to death due to any cause in the intention-to-treat population. This trial is registered with ClinicalTrials.gov, NCT02456506. FINDINGS: Between July 10, 2015, and Dec 23, 2019, 178 patients were screened for eligibility, 144 of whom were enrolled and randomly assigned to hyperfractionation or standard fractionation (n=72 in each group). 35 (24%) participants were women and 109 (76%) were men. After a median follow-up of 45·0 months (IQR 37·3-53·3), there was a significantly lower incidence of grade 3 or worse late radiation-induced toxicity in the hyperfractionation group (23 [34%] of 68 patients) versus the standard fractionation group (39 [57%] of 68 patients; between-group difference -23% [95% CI -39 to -7]; p=0·023). Patients in the hyperfractionation group had better 3-year overall survival than those in the standard fractionation group (74·6% [95% CI 64·4 to 84·8] vs 55·0% [43·4 to 66·6]; hazard ratio for death 0·54 [95% CI 0·33 to 0·88]; p=0·014). There were fewer grade 5 late complications in the hyperfractionation group (five [7%] nasal haemorrhage) than in the standard fractionation group (16 [24%], including two [3%] nasopharyngeal necrosis, 11 [16%] nasal haemorrhage, and three [4%] temporal lobe necrosis). INTERPRETATION: Hyperfractionated intensity-modulated radiotherapy could significantly decrease the rate of severe late complications and improve overall survival among patients with locally advanced recurrent nasopharyngeal carcinoma. Our findings suggest that hyperfractionated intensity-modulated radiotherapy could be used as the standard of care for these patients. FUNDING: Key-Area Research and Development of Guangdong Province, the National Natural Science Foundation of China, the Special Support Program for High-level Talents in Sun Yat-sen University Cancer Center, the Guangzhou Science and Technology Plan Project, and the National Ten Thousand Talents Program Science and Technology Innovation Leading Talents, Sun Yat-Sen University Clinical Research 5010 Program.


Assuntos
Neoplasias Nasofaríngeas , Radioterapia de Intensidade Modulada , Masculino , Humanos , Feminino , Carcinoma Nasofaríngeo/radioterapia , Radioterapia de Intensidade Modulada/efeitos adversos , Recidiva Local de Neoplasia/radioterapia , Neoplasias Nasofaríngeas/radioterapia , Hemorragia
15.
Cancer Immunol Immunother ; 73(11): 230, 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39249605

RESUMO

BACKGROUND: Adjuvant nivolumab reduces recurrence in patients with locoregional esophageal cancer who had pathological residual disease after neoadjuvant chemoradiotherapy and R0 resection. However, the efficacy of adjuvant anti-PD-1 therapy in patients at higher risk of recurrence remains unclear. METHODS: This phase II trial (ClinicalTrials.gov identifier: NCT03322267) enrolled patients with locally advanced esophageal squamous cell carcinoma (ESCC) received neoadjuvant chemoradiotherapy plus esophagectomy but still had various risk factors for recurrence, such as involved or close margins (≤ 1 mm), extranodal extension of the involved lymph nodes, and the ypN2-3 stage. Patients received adjuvant therapy composed of a course of cisplatin-based chemoradiotherapy and pembrolizumab (200 mg, IV every 3 weeks) for 18 cycles. The primary endpoint was 1-year relapse-free survival (RFS) rate. RESULTS: Twenty-five patients were enrolled. The risk factors were tumor margins of ≤ 1 mm (18 patients), extranodal extension of the involved lymph nodes (9 patients), and the ypN2-3 stage (9 patients). The median follow-up duration was 21.6 months (95% CI: 18.7-33.2). The rate of 1-year RFS was 60.0%. The median duration of RFS and overall survival was 14.3 (95% CI: 9.0-19.5) and 21.6 (95% CI: 0.0-45.5) months, respectively. Treatment-emergent adverse events of any grade and those of ≥ 3 grade occurred in 56% and 8% of all patients receiving cisplatin-based chemoradiotherapy and in 79.2% and 12.5% of those receiving pembrolizumab. CONCLUSIONS: Adjuvant chemoradiotherapy followed by pembrolizumab is feasible and may be associated with improved 1-year RFS rate in patients at high risk of recurrence after trimodality therapy for locally advanced ESCC. Trial registration number ClinicalTrials.gov (No. NCT03322267).


Assuntos
Anticorpos Monoclonais Humanizados , Quimiorradioterapia Adjuvante , Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Terapia Neoadjuvante , Recidiva Local de Neoplasia , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/efeitos adversos , Carcinoma de Células Escamosas do Esôfago/terapia , Carcinoma de Células Escamosas do Esôfago/mortalidade , Carcinoma de Células Escamosas do Esôfago/patologia , Idoso , Neoplasias Esofágicas/terapia , Neoplasias Esofágicas/mortalidade , Neoplasias Esofágicas/patologia , Recidiva Local de Neoplasia/terapia , Terapia Neoadjuvante/métodos , Quimiorradioterapia Adjuvante/métodos , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Esofagectomia
16.
Small ; 20(25): e2311056, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38377262

RESUMO

The poor efficiency and low immunogenicity of photodynamic therapy (PDT), and the immunosuppressive tumor microenvironment (ITM) lead to tumor recurrence and metastasis. In this work, TCPP-TER-Zn@RSV nanosheets (TZR NSs) that co-assembled from the endoplasmic reticulum (ER)-targeting photosensitizer TCPP-TER-Zn nanosheets (TZ NSs for short) and the autophagy promoting and indoleamine-(2, 3)-dioxygenase (IDO) inhibitor-like resveratrol (RSV) are fabricated to enhance antitumor PDT. TZR NSs exhibit improved therapeutic efficiency and amplified immunogenic cancer cell death (ICD) by ER targeting PDT and ER autophagy promotion. TZR NSs reversed the ITM with an increase of CD8+ T cells and reduce of immunosuppressive Foxp3 regulatory T cells, which effectively burst antitumor immunity thus clearing residual tumor cells. The ER-targeting TZR NSs developed in this paper presents a simple but valuable reference for high-efficiency tumor photodynamic immunotherapy.


Assuntos
Autofagia , Retículo Endoplasmático , Imunoterapia , Fotoquimioterapia , Microambiente Tumoral , Microambiente Tumoral/efeitos dos fármacos , Fotoquimioterapia/métodos , Imunoterapia/métodos , Autofagia/efeitos dos fármacos , Retículo Endoplasmático/metabolismo , Animais , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/uso terapêutico , Nanoestruturas/química , Humanos , Linhagem Celular Tumoral , Camundongos
17.
Bioconjug Chem ; 35(4): 453-456, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38491941

RESUMO

mRNA therapeutics hold great promise for disease treatment, yet a key challenge lies in achieving site-specific mRNA delivery to maximize therapeutic efficacy while minimizing off-target side effects. This viewpoint delves into multiple complementary targeting strategies to achieve precise site-specific mRNA delivery, covering topics of administration routes, passive targeting, and active targeting. It highlights the critical importance of rationally designed nanocarriers for obtaining desired therapeutic effects and accelerating the clinical translation of mRNA therapeutics.


Assuntos
Sistemas de Liberação de Medicamentos , Nanopartículas , Portadores de Fármacos
18.
Acc Chem Res ; 56(13): 1766-1779, 2023 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-37314368

RESUMO

Development of multifunctional nanoparticles (NPs) with desired properties is a significant topic in the field of nanotechnology and has been anticipated to revolutionize cancer diagnosis and treatment modalities. The surface character is one of the most important parameters of NPs that can directly affect their in vivo fate, bioavailability, and final theranostic outcomes and thus should be carefully tuned to maximize the diagnosis and treatment effects while minimizing unwanted side effects. Surface engineered NPs have utilized various surface functionality types and approaches to meet the requirements of cancer therapy and imaging. Despite the various strategies, these surface modifications generally serve similar purposes, namely, introducing therapeutic/imaging modules, improving stability and circulation, enhancing targeting ability, and achieving controlled functions. These surface engineered NPs hence could be applied in various cancer diagnosis and treatment scenarios and continuously contribute to the clinical translation of the next-generation NP-based platforms toward cancer theranostics.In this Account, we present recent advances and research efforts on the development of NP surface engineering toward cancer theranostics. First, we summarize the general strategies for NP surface engineering. Various types of surface functionalities have been applied including inorganic material-based functionality, organic material-based functionality like small molecules, polymers, nucleic acids, peptides, proteins, carbohydrates, antibodies, etc., and biomembrane-based functionality. These surface modifications can be realized by prefabrication or postfabrication functionalization, driven by covalent conjugations or noncovalent interactions. Second, we highlight the general aims of these different NPs surface functionalities. Different therapeutic and diagnostic modules, such as nanozymes, antibodies, and imaging contrast agents, have been modified on the surface of NPs to achieve theranostic function. Surface modification also can improve stability and circulation of NPs by protecting the NPs from immune recognition and clearance. In addition, to achieve targeted therapy and imaging, various targeting moieties have been attached on the NP surface to enhance active targeting ability to tissues or cells of interest. Furthermore, the NP surfaces can be tailored to achieve controlled functions which only respond to specific internal (e.g., pH, thermal, redox, enzyme, hypoxia) or external (e.g., light, ultrasound) triggers at the precise action sites. Finally, we present our perspective on the remaining challenges and future developments in this significant and rapidly evolving field. We hope this Account can offer an insightful overlook on the recent progress and an illuminating prospect on the advanced strategies, promoting more attention in this area and adoption by more scientists in various research fields, accelerating the development of NP surface engineering with a solid foundation and broad cancer theranostics applications.


Assuntos
Nanopartículas , Neoplasias , Humanos , Medicina de Precisão , Neoplasias/diagnóstico por imagem , Neoplasias/terapia , Nanopartículas/uso terapêutico , Nanopartículas/química , Engenharia
19.
Opt Lett ; 49(9): 2269-2272, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38691696

RESUMO

We proposed spectrally temporally cascaded optical parametric amplification (STOPA) using pump energy recycling to simultaneously increase spectral bandwidth and conversion efficiency in optical parametric amplification (OPA). Using BiB3O6 and KTiOAsO4 nonlinear crystals, near-single-cycle mid-infrared (MIR) pulses with maximum energy conversion efficiencies exceeding 25% were obtained in simulations. We successfully demonstrated sub-two-cycle, CEP-stable pulse generation at 1.8 µm using a four-step STOPA system in the experiment. This method provides a solution to solve the limitations of the gain bandwidth of nonlinear crystals and the low conversion efficiency in broadband OPA systems, which is helpful for intense attosecond pulse generation and strong laser field physics studies.

20.
J Neurol Neurosurg Psychiatry ; 95(3): 222-228, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-37875337

RESUMO

BACKGROUND: Tai Chi has shown beneficial effects on the motor and non-motor symptoms of Parkinson's disease (PD), but no study has reported the effect of long-term Tai Chi training. OBJECTIVE: To examine whether long-term Tai Chi training can maintain improvement in patients with PD. METHODS: Cohorts of patients with PD with Tai Chi training (n=143) and patients with PD without exercise as a control group (n=187) were built from January 2016. All subjects were assessed at baseline and in November 2019, October 2020 and June 2021. A logarithmic linear model was used to analyse rating scales for motor and non-motor symptoms. The need to increase antiparkinsonian therapies was presented as a Kaplan-Meier plot and as a box plot. The bootstrap method was used to resample for statistical estimation. RESULTS: Tai Chi training reduced the annual changes in the deterioration of the Unified Parkinson's Disease Rating Scale and delayed the need for increasing antiparkinsonian therapies. The annual increase in the levodopa equivalent daily dosage was significantly lower in the Tai Chi group. Moreover, patients benefited from Tai Chi training in motor symptoms, non-motor symptoms and complications. CONCLUSION: Tai Chi training has a long-term beneficial effect on PD, with an improvement in motor and non-motor symptoms and reduced complications. TRIAL REGISTRATION NUMBER: NCT05447975.


Assuntos
Doença de Parkinson , Tai Chi Chuan , Humanos , Tai Chi Chuan/métodos , Seguimentos , Doença de Parkinson/terapia , Terapia por Exercício/métodos , Antiparkinsonianos , Qualidade de Vida
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