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1.
Curr Opin Oncol ; 36(5): 430-436, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39007226

RESUMO

PURPOSE OF REVIEW: Antibody-drug conjugates (ADCs), consisting of monoclonal antibodies (mAbs) covalently linked to cytotoxic drugs via chemical linkers, are a kind of promising tumor immunotherapy. ADCs also face a number of challenges, including unavoidable adverse effects, drug resistance, tumor targeting and payload release. To address these issues, in addition to optimizing the individual components of ADCs, such as new payloads, linkage sites and new targets, and using bispecific antibodies to increase precision, attention should be paid to optimizing the dosage of ADCs. RECENT FINDINGS: There are currently 7 ADCs approved for marketing by the Food and Drug Administration (FDA) for hematological malignancies, and dozens of other ADCs are either in clinical trials or in the process of applying for marketing. In recent clinical studies targeting ADCs in hematologic malignancies, in addition to validating effectiveness in different indications, researchers have attempted to combine ADCs with other chemotherapeutic agents in anticipation of increased therapeutic efficacy. Furthermore, the availability of bispecific antibodies may increase the safety and efficacy of ADCs. SUMMARY: This review summarized the progress of research on ADCs in hematological malignancies, the challenges being faced, and possible future directions to improve the efficacy of ADCs, which can provide novel insight into the future exploration of ADCs in the treatment of hematological malignancies.


Assuntos
Neoplasias Hematológicas , Imunoconjugados , Humanos , Neoplasias Hematológicas/tratamento farmacológico , Neoplasias Hematológicas/imunologia , Imunoconjugados/uso terapêutico , Anticorpos Biespecíficos/uso terapêutico , Antineoplásicos Imunológicos/uso terapêutico
2.
Mod Pathol ; 37(11): 100594, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39147032

RESUMO

Alveolar rhabdomyosarcoma (ARMS) with FOXO1 gene rearrangements is an aggressive pediatric rhabdomyosarcoma subtype that is prognostically distinct from embryonal rhabdomyosarcoma and fusion-negative ARMS. Here, we report 2 cases of ARMS with PAX3::MAML3 fusions. The tumors arose in an infant and an adolescent as stage IV metastatic disease (by Children's Oncology Group staging system). Histologically, both cases were small round blue cell tumors arranged in vague nests and solid sheets that were diffusely positive for desmin and myogenin. By methylation profiling and unsupervised clustering analysis, the tumors clustered with ARMS with classic FOXO1 rearrangements and ARMS with variant PAX3::NCOA1/INO80D fusions, but not with biphenotypic sinonasal sarcoma (BSNS) with PAX3::MAML3/NCOA2/FOXO1/YAP1 fusions nor with other small round blue cell tumors, including embryonal rhabdomyosarcoma. The differentially methylated genes between ARMS and BSNS were highly enriched in genes involved in myogenesis, and 21% of these genes overlap with target genes of the PAX3::FOXO1 fusion transcription factor. On follow-up after initiation of vincristine/actinomycin/cyclophosphamide chemotherapy, the tumors showed partial and complete clinical responses, consistent with typical upfront chemotherapy responsiveness of ARMS with the classic FOXO1 rearrangement. We conclude that PAX3::MAML3 is a novel variant fusion of ARMS, which displays a methylation signature distinct from BSNS despite sharing similar PAX3 fusions. These findings highlight the utility of methylation profiling in classifying ARMS with noncanonical fusions.

3.
Angew Chem Int Ed Engl ; 63(14): e202319690, 2024 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-38320965

RESUMO

Given the scarcity of novel antibiotics, the eradication of bacterial biofilm infections poses formidable challenges. Upon bacterial infection, the host restricts Fe ions, which are crucial for bacterial growth and maintenance. Having coevolved with the host, bacteria developed adaptive pathways like the hemin-uptake system to avoid iron deficiency. Inspired by this, we propose a novel strategy, termed iron nutritional immunity therapy (INIT), utilizing Ga-CT@P nanocomposites constructed with gallium, copper-doped tetrakis (4-carboxyphenyl) porphyrin (TCPP) metal-organic framework, and polyamine-amine polymer dots, to target bacterial iron intakes and starve them. Owing to the similarity between iron/hemin and gallium/TCPP, gallium-incorporated porphyrin potentially deceives bacteria into uptaking gallium ions and concurrently extracts iron ions from the surrounding bacteria milieu through the porphyrin ring. This strategy orchestrates a "give and take" approach for Ga3+/Fe3+ exchange. Simultaneously, polymer dots can impede bacterial iron metabolism and serve as real-time fluorescent iron-sensing probes to continuously monitor dynamic iron restriction status. INIT based on Ga-CT@P nanocomposites induced long-term iron starvation, which affected iron-sulfur cluster biogenesis and carbohydrate metabolism, ultimately facilitating biofilm eradication and tissue regeneration. Therefore, this study presents an innovative antibacterial strategy from a nutritional perspective that sheds light on refractory bacterial infection treatment and its future clinical application.


Assuntos
Infecções Bacterianas , Gálio , Porfirinas , Humanos , Ferro/metabolismo , Hemina/metabolismo , Bactérias/metabolismo , Antibacterianos/metabolismo , Biofilmes , Gálio/farmacologia , Porfirinas/farmacologia , Porfirinas/metabolismo , Infecções Bacterianas/tratamento farmacológico , Homeostase , Íons/metabolismo , Polímeros/metabolismo
4.
BMC Cardiovasc Disord ; 23(1): 156, 2023 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-36973644

RESUMO

BACKGROUND AND OBJECTIVES: Real-time blood flow variation is crucial for understanding the dynamic development of coronary atherosclerosis. The main objective of this study is to investigate the effect of varying extent of stenosis on the hemodynamic features in left anterior descending coronary artery. METHODS: Various Computational fluid dynamics (CFD) models were constructed with patient-specific CT image data, using actual fractional flow reserve (FFR) as boundary conditions to provide a real-time quantitative description of hemodynamic properties. The hemodynamic parameters, such as the local and instantaneous wall shear stress (WSS), oscillating shear index (OSI) and relative residence time (RRT), blood flow velocity and pressure drop during various phases of cardiac cycle were provided in detail. RESULTS: There was no evident variation in hemodynamic parameters in the cases of less than 50% stenosis while there were abrupt and dramatic changes in hemodynamics when the stenosis aggravated from 60 to 70%. Furthermore, when the stenosis was beyond 70%, there existed substantial pressure difference, WSS, and blood flow velocity in the center of the stenosis. Although OSI and RRT increased along with the aggravation of stenosis, they appeared with obvious abnormalities across all cases, even in mild stenosis. CONCLUSION: The simulation could present a dynamic and comprehensive profile of how hemodynamic parameters vary in accordance with divergent severities of stenosis, which could serve as an effective reference for the clinicians to have a deeper insight into the pathological mechanism of coronary atherosclerosis and stenosis.


Assuntos
Doença da Artéria Coronariana , Estenose Coronária , Reserva Fracionada de Fluxo Miocárdico , Humanos , Vasos Coronários , Constrição Patológica , Modelos Cardiovasculares , Hemodinâmica , Velocidade do Fluxo Sanguíneo , Estresse Mecânico
5.
Int J Mol Sci ; 24(3)2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36769328

RESUMO

Both periodontitis and Coronavirus disease 2019 (COVID-19) pose grave threats to public health and social order, endanger human life, and place a significant financial strain on the global healthcare system. Since the COVID-19 pandemic, mounting research has revealed a link between COVID-19 and periodontitis. It is critical to comprehend the immunological mechanisms of the two illnesses as well as their immunological interaction. Much evidence showed that there are many similar inflammatory pathways between periodontitis and COVID-19, such as NF-κB pathway, NLRP3/IL-1ß pathway, and IL-6 signaling pathway. Common risk factors such as gender, lifestyle, and comorbidities contribute to the severity of both diseases. Revealing the internal relationship between the two diseases is conducive to the treatment of the two diseases in an emergency period. It is also critical to maintain good oral hygiene and a positive attitude during treatment. This review covers four main areas: immunological mechanisms, common risk factors, evidence of the association between the two diseases, and possible interventions and potential targets. These will provide potential ideas for drug development and clinical treatment of the two diseases.


Assuntos
COVID-19 , Periodontite , Humanos , SARS-CoV-2 , Pandemias , Periodontite/epidemiologia , NF-kappa B
6.
Planta ; 256(4): 77, 2022 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-36088613

RESUMO

MAIN CONCLUSION: This study displayed the transcriptional regulation network of key regulators and downstream pathway in seedling morphogenesis of Brassica napus under different light quality. Plants undergo photomorphogenesis upon the presence of light, mediated by different light (e.g., blue, red, and far-red) signaling pathways. Although the light signaling pathway has been well documented in Arabidopsis, the underlying mechanisms were studied to a less extent in other plant species including Brassica napus. In this study, we investigated the effect of different light qualities (white, blue, red, and far-red light) on the hypocotyl elongation in B. napus, and performed the transcriptomic analysis of seedlings in response to different light qualities. The results showed that hypocotyl elongation was slightly inhibited by red light, while it was strongly inhibited by blue/far-red light. Transcriptome analysis identified 9748 differentially expressed genes (DEGs) among treatments. Gene ontology (GO) enrichment analysis of DEGs showed that light-responsive and photosynthesis-related genes were highly expressed in response to blue/far-red light rather than in red light. Furthermore, the key genes in light signaling (i.e., PHYB, HY5, HYH, HFR1, and PIF3) exhibited distinct expression patterns between blue/far-red and red light treatments. In addition, subgenome dominant expression of homoeologous genes were observed for some genes, such as PHYA, PHYB, HFR1, and BBXs. The current study displayed a comprehensive dissection of light-mediated transcriptional regulation network, including light signaling, phytohormone, and cell elongation/modification, which improved the understanding on the underlying mechanism of light-regulated hypocotyl growth in B. napus.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Brassica napus , Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Brassica napus/genética , Brassica napus/metabolismo , Regulação da Expressão Gênica de Plantas , Hipocótilo , Plântula/genética , Plântula/metabolismo
7.
Int J Cancer ; 146(10): 2810-2821, 2020 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-31465111

RESUMO

Chemotherapy-induced peripheral neuropathy (CIPN) is a significant side effect of chemotherapeutics. The mechanisms of CIPN remain substantially unidentified, although inflammation-induced peripheral sensitization has been indicated as an important factor. Here, we aimed to illustrate the role of the matrix metalloproteinase (MMP)-9-related signaling pathway in the process of CIPN. Oxaliplatin (L-OHP) was administered to mice to establish the CIPN model. Gelatin zymography was used to measure MMP-9/2 activities. Western blotting and immunohistochemistry were used to measure the expression of high-mobility group box-1 (HMGB-1), calcitonin gene-related peptide and ionized calcium-binding adapter molecule 1. Mechanical withdrawal was measured by von Frey hairs testing. Raw 264.7 cells and SH-SY5Y cells were cultured to investigate cell signaling in vitro. Here, we report that L-OHP-induced mechanical pain in mice with significant MMP-9/2 activation in dorsal root ganglion (DRG) neurons. MMP-9 inhibition or knockout alleviated the occurrence of CIPN directly. MMP-9/2 were released from macrophages and neurons in the DRG via the HMGB-1-toll-like receptor 4 (TLR4)-phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) axis, because MMP-9/2 activities could be reduced by macrophage scavengers or PI3Kγ knockout in CIPN mice. The in vitro data revealed that induced MMP-9 activity by recombinant HMGB-1 could be abolished by TLR4, PI3K or Akt inhibitors. Finally, it was shown that N-acetyl-cysteine (NAC) could reduce MMP-9/2 activities and attenuate CIPN effectively and safely. The HMGB-1-TLR4-PI3K/Akt-MMP-9 axis is involved in the crosstalk between macrophages and neurons in the pathological process of CIPN in mice. Direct inhibition of MMP-9 by NAC may be a potential therapeutic regimen for CIPN treatment.


Assuntos
Antineoplásicos/toxicidade , Gânglios Espinais/metabolismo , Doenças do Sistema Nervoso Periférico/induzido quimicamente , Doenças do Sistema Nervoso Periférico/metabolismo , Transdução de Sinais/efeitos dos fármacos , Animais , Gânglios Espinais/efeitos dos fármacos , Proteína HMGB1/efeitos dos fármacos , Proteína HMGB1/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Metaloproteinase 9 da Matriz/efeitos dos fármacos , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Oxaliplatina/toxicidade , Fosfatidilinositol 3-Quinases/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Células RAW 264.7 , Transdução de Sinais/fisiologia , Receptor 4 Toll-Like/efeitos dos fármacos , Receptor 4 Toll-Like/metabolismo
8.
Int J Cancer ; 144(11): 2707-2717, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-30565669

RESUMO

Our previous study of DNA methylation in the pediatric soft tissue tumor rhabdomyosarcoma (RMS) demonstrated that fusion-positive (FP) and fusion-negative (FN) RMS tumors exhibit distinct DNA methylation patterns. To further examine the significance of DNA methylation differences in RMS, we investigated genome-wide DNA methylation profiles in discovery and validation cohorts. Unsupervised analysis of DNA methylation data identified novel distinct subsets associated with the specific fusion subtype in FP RMS and with RAS mutation status in FN RMS. Furthermore, the methylation pattern in normal muscle is most similar to the FN subset with wild-type RAS mutation status. Several biologically relevant genes were identified with methylation and expression differences between the two fusion subtypes of FP RMS or between the RAS wild-type and mutant subsets of FN RMS. Genomic localization studies showed that promoter and intergenic regions were hypomethylated and the 3' untranslated regions were hypermethylated in FP compared to FN tumors. There was also a significant difference in the distribution of PAX3-FOXO1 binding sites between genes with and without differential methylation. Moreover, genes with PAX3-FOXO1 binding sites and promoter hypomethylation exhibited the highest frequency of overexpression in FP tumors. Finally, a comparison of RMS model systems revealed that patient-derived xenografts most closely recapitulate the DNA methylation patterns found in human RMS tumors compared to cell lines and cell line-derived xenografts. In conclusion, these findings highlight the interaction of epigenetic changes with mutational alterations and transcriptional organization in RMS tumors, and contribute to improved molecular categorization of these tumors.


Assuntos
Metilação de DNA , Regulação Neoplásica da Expressão Gênica , Neoplasias Musculares/genética , Proteínas de Fusão Oncogênica/genética , Fatores de Transcrição Box Pareados/genética , Rabdomiossarcoma/genética , Animais , Linhagem Celular Tumoral , Proliferação de Células , Criança , Conjuntos de Dados como Assunto , Epigênese Genética , Humanos , Neoplasias Musculares/patologia , Músculo Estriado/patologia , Mutação Puntual , Regiões Promotoras Genéticas/genética , Rabdomiossarcoma/patologia , Análise Serial de Tecidos , Ensaios Antitumorais Modelo de Xenoenxerto , Proteínas ras
9.
Mod Pathol ; 28(9): 1214-24, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26226845

RESUMO

Rhabdomyosarcoma comprises two major subtypes, fusion positive (PAX3-FOXO1 or PAX7-FOXO1) and fusion negative. To investigate the significance of DNA methylation in these subtypes, we analyzed methylation profiles of 37 rhabdomyosarcoma tumors and 10 rhabdomyosarcoma cell lines, as well as 8 normal tissues. Unsupervised clustering of DNA methylation clearly distinguished the fusion-positive and fusion-negative subsets. The fusion-positive tumors showed substantially lower overall levels of methylation compared with fusion-negative tumors. Comparison with the methylation pattern of normal skeletal muscle and bone marrow indicates that fusion-negative rhabdomyosarcoma is more similar to these normal tissues compared with fusion-positive rhabdomyosarcoma, and suggests that many of the methylation differences between these subtypes arise from 'aberrant' hyper- and hypomethylation events in fusion-positive rhabdomyosarcoma. Integrative methylation and gene expression analysis revealed that methylation differences between fusion-positive and fusion-negative tumors could either be positively or negatively associated with mRNA expression. There was no significant difference in the distribution of PAX3-FOXO1-binding sites between genes with and without differential methylation. However, the finding that PAX3-FOXO1-binding sites were enriched among genes that were both differentially methylated and differentially expressed suggests that the fusion protein interacts with DNA methylation to regulate target gene expression. An 11-gene DNA methylation signature, classifying the rhabdomyosarcoma tumors into fusion-positive and fusion-negative subsets, was established and validated by pyrosequencing assays. Notably, EMILIN1 (part of the 11-gene signature) showed higher methylation and lower mRNA expression in fusion-positive compared with fusion-negative tumors, and demonstrated demethylation and re-expression in multiple fusion-positive cell lines after treatment with 5-aza-2'-deoxycytidine. In conclusion, our study demonstrates that fusion-positive and fusion-negative rhabdomyosarcoma tumors possess characteristic methylation profiles that contribute to the expression differences between these fusion subtypes. These findings indicate an important relationship between fusion status and epigenetic changes in rhabdomyosarcoma, present a novel approach for ascertaining fusion status, and may identify new therapeutic targets in rhabdomyosarcoma.


Assuntos
Metilação de DNA/genética , Rabdomiossarcoma/genética , Neoplasias de Tecidos Moles/genética , Análise por Conglomerados , Humanos , Hibridização in Situ Fluorescente , Análise de Sequência com Séries de Oligonucleotídeos , Proteínas de Fusão Oncogênica , Fatores de Transcrição Box Pareados , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transcriptoma
10.
Zhonghua Yi Xue Za Zhi ; 95(29): 2363-7, 2015 Aug 04.
Artigo em Zh | MEDLINE | ID: mdl-26711071

RESUMO

OBJECTIVE: To assess the feasibility of individual contrast injection protocols in triple-rule-out computed tomography examination using a dual-source Flash-chest-pain technique. METHODS: From April to August 2014, 63 patients with undifferentiated acute chest pain underwent ECG-synchronized dual-spiral chest CT angiography. 31 Patients, who all had low (<65 bpm) and stable heart rate underwent TRO CT angiography in a Flash mode, with an individual triphasic contrast protocol based on weight (350 mgI/ml, A: 0.7 ml/kg, setting 10 s duration time; B: 8 s mixture of the contrast agent and saline at the same rate; C: 6-7 s saline at the same rate). In contrast, the other patients, who had random heart rate, underwent TRO CT angiography in a traditional retrospectively mode with an identical biphasic contrast protocol (350 mgI/ml, A: contrast agent 90 ml, B: saline 40 ml, injection rate 5 ml/s). Quantitative image analysis assessed vessel attenuation of aorta, coronary and pulmonary artery, signal-to-noise ratio (SNR) and contrast-to noise ratio (CNR). Subjective image was assessed on a 5 point scale (1: excellent, 5:non-diagnosis) by two blind observers. The effective dose was calculated from the dose length product (DLP) using a conversion coefficient of 0.017 mSv·mGy(-1)·cm(-1). RESULTS: There was no significant difference of aorta and coronary artery attenuation, noise, SNR, CNR or subjective image quality between both patient groups. Pulmonary artery attenuation was lower in test group than in control group, but it also can meet the diagnostic criteria. Moreover, the mean contrast agent and the effective dose were lower in test group than in control group (72±10) vs (90±0) ml, P<0.01 and (3.0±0.3) vs (18.8±2.7) mSv, P<0.01. CONCLUSION: As to patients with low and stable heart rate, this individual contrast protocol along with dual-source high-pith technique, is capable of achieving satisfactory image which could meet the diagnostic requirements with lower contrast agent and lower effective dose.


Assuntos
Angiografia , Dor no Peito , Meios de Contraste , Frequência Cardíaca , Humanos , Injeções Intravenosas , Artéria Pulmonar , Estudos Retrospectivos , Tomografia Computadorizada Espiral
11.
Zhonghua Yi Xue Za Zhi ; 95(11): 810-3, 2015 Mar 24.
Artigo em Zh | MEDLINE | ID: mdl-26080910

RESUMO

OBJECTIVE: To compare the image qualities of different contrast medium injection protocols for 128-slice dual-source computed tomography (DSCT) in children with Tetralogy of Fallot (TOF). METHODS: A total of 60 patients with TOF were randomly divided into groups A, B and C (n = 20 each). And 128-slice DSCT angiography was performed with sequential mode according to the contrast injection protocols: the volume of contrast medium was 1.2, 1.2 and 1.5 ml/kg and the injection time 10, 12 and 15 s respectively. Contrast medium was followed by a saline bolus for 10 s. Enhancement and noise of ascending aorta, main pulmonary artery, descending aorta and left ventricle were quantified. Signal-to-noise ratio (SNR), dose-length product (DLP) and effective dose (ED) were calculated. The absolute difference of left and right ventricular attenuations was calculated to represent the image uniformity. Subjective image quality was assessed by two radiologists in consensus. RESULTS: No significant difference existed in attenuation or SNR between three groups in the same evaluated anatomic regions. No significant difference existed in image quality of heart chamber and great vessels. The image uniformity (81 ± 65) and subjective image quality of artifacts of superior vena cava were significantly better in group B than those in groups A and C (179 ± 178, 106 ± 66, P < 0.05). CONCLUSION: The contrast medium injection protocol of 1.2 ml/kg volume contrast medium injected within 12 s may enhance the image quality of 128-slice dual-source CT in children with TOF.


Assuntos
Tetralogia de Fallot , Tomografia Computadorizada por Raios X , Angiografia , Criança , Meios de Contraste , Humanos , Injeções
12.
Cancer Commun (Lond) ; 2024 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-39073258

RESUMO

Immune checkpoints are differentially expressed on various immune cells to regulate immune responses in tumor microenvironment. Tumor cells can activate the immune checkpoint pathway to establish an immunosuppressive tumor microenvironment and inhibit the anti-tumor immune response, which may lead to tumor progression by evading immune surveillance. Interrupting co-inhibitory signaling pathways with immune checkpoint inhibitors (ICIs) could reinvigorate the anti-tumor immune response and promote immune-mediated eradication of tumor cells. As a milestone in tumor treatment, ICIs have been firstly used in solid tumors and subsequently expanded to hematological malignancies, which are in their infancy. Currently, immune checkpoints have been investigated as promising biomarkers and therapeutic targets in hematological malignancies, and novel immune checkpoints, such as signal regulatory protein α (SIRPα) and tumor necrosis factor-alpha-inducible protein 8-like 2 (TIPE2), are constantly being discovered. Numerous ICIs have received clinical approval for clinical application in the treatment of hematological malignancies, especially when used in combination with other strategies, including oncolytic viruses (OVs), neoantigen vaccines, bispecific antibodies (bsAb), bio-nanomaterials, tumor vaccines, and cytokine-induced killer (CIK) cells. Moreover, the proportion of individuals with hematological malignancies benefiting from ICIs remains lower than expected due to multiple mechanisms of drug resistance and immune-related adverse events (irAEs). Close monitoring and appropriate intervention are needed to mitigate irAEs while using ICIs. This review provided a comprehensive overview of immune checkpoints on different immune cells, the latest advances of ICIs and highlighted the clinical applications of immune checkpoints in hematological malignancies, including biomarkers, targets, combination of ICIs with other therapies, mechanisms of resistance to ICIs, and irAEs, which can provide novel insight into the future exploration of ICIs in tumor treatment.

13.
Front Oncol ; 14: 1399442, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39224814

RESUMO

Introduction: Alternative lengthening of telomeres (ALT) occurs in sarcomas and ALT cancers share common mechanisms of therapy resistance or sensitivity. Telomeric DNA C-circles are self-primed circular telomeric repeats detected with a PCR assay that provide a sensitive and specific biomarker exclusive to ALT cancers. We have previously shown that 23% of high-risk neuroblastomas are of the ALT phenotype. Here, we investigate the frequency of ALT in Ewing's family sarcoma (EFS), rhabdomyosarcoma (RMS), and osteosarcoma (OS) by analyzing DNA from fresh frozen primary tumor samples utilizing the real-time PCR C-circle Assay (CCA). Methods: We reviewed prior publications on ALT detection in pediatric sarcomas. DNA was extracted from fresh frozen primary tumors, fluorometrically quantified, C-circles were selectively enriched by isothermal rolling cycle amplification and detected by real-time PCR. Results: The sample cohort consisted of DNA from 95 EFS, 191 RMS, and 87 OS primary tumors. One EFS and 4 RMS samples were inevaluable. Using C-circle positive (CC+) cutoffs previously defined for high-risk neuroblastoma, we observed 0 of 94 EFS, 5 of 187 RMS, and 62 of 87 OS CC+ tumors. Conclusions: Utilizing the ALT-specific CCA we observed ALT in 0% of EFS, 2.7% of RMS, and 71% of OS. These data are comparable to prior studies in EFS and OS using less specific ALT markers. The CCA can provide a robust and sensitive means of identifying ALT in sarcomas and has potential as a companion diagnostic for ALT targeted therapeutics.

14.
Adv Mater ; 36(13): e2310529, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38145555

RESUMO

Metal nanoclusters (NCs) are well-recognized novel nano-agents that hold great promise for applications in nanomedicine because of their ultrafine size, low toxicity, and high renal clearance. As foreign substances, however, an in-depth understanding of the bioresponses to metal NCs is necessary but is still far from being realized. Herein, this review is deployed to summarize the biofates of metal NCs at various biological levels, emphasizing their multiscale bioresponses at the molecular, cellular, and organismal levels. In the parts-to-whole schema, the interactions between biomolecules and metal NCs are discussed, presenting typical protein-dictated nano-bio interfaces, hierarchical structures, and in vivo trajectories. Then, the accumulation, internalization, and metabolic evolution of metal NCs in the cellular environment and as-imparted theranostic functionalization are demonstrated. The organismal metabolism and transportation processes of the metal NCs are subsequently distilled. Finally, this review ends with the conclusions and perspectives on the outstanding issues of metal NC-mediated bioresponses in the near future. This review is expected to provide inspiration for tailoring the customization of metal NC-based nano-agents to meet practical requirements in different sectors of nanomedicine.


Assuntos
Nanopartículas Metálicas , Nanopartículas Metálicas/química , Metais , Nanomedicina , Proteínas , Medicina de Precisão
15.
mSphere ; 9(6): e0076223, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38747590

RESUMO

The RNA chaperone Hfq acts as a global regulator of numerous biological processes, such as carbon/nitrogen metabolism and environmental adaptation in plant-associated diazotrophs; however, its target RNAs and the mechanisms underlying nitrogen fixation remain largely unknown. Here, we used enhanced UV cross-linking immunoprecipitation coupled with high-throughput sequencing to identify hundreds of Hfq-binding RNAs probably involved in nitrogen fixation, carbon substrate utilization, biofilm formation, and other functions. Collectively, these processes endow strain A1501 with the requisite capabilities to thrive in the highly competitive rhizosphere. Our findings revealed a previously uncharted landscape of Hfq target genes. Notable among these is nifM, encoding an isomerase necessary for nitrogenase reductase solubility; amtB, encoding an ammonium transporter; oprB, encoding a carbohydrate porin; and cheZ, encoding a chemotaxis protein. Furthermore, we identified more than 100 genes of unknown function, which expands the potential direct regulatory targets of Hfq in diazotrophs. Our data showed that Hfq directly interacts with the mRNA of regulatory proteins (RsmA, AlgU, and NifA), regulatory ncRNA RsmY, and other potential targets, thus revealing the mechanistic links in nitrogen fixation and other metabolic pathways. IMPORTANCE: Numerous experimental approaches often face challenges in distinguishing between direct and indirect effects of Hfq-mediated regulation. New technologies based on high-throughput sequencing are increasingly providing insight into the global regulation of Hfq in gene expression. Here, enhanced UV cross-linking immunoprecipitation coupled with high-throughput sequencing was employed to identify the Hfq-binding sites and potential targets in the root-associated Pseudomonas stutzeri A1501 and identify hundreds of novel Hfq-binding RNAs that are predicted to be involved in metabolism, environmental adaptation, and nitrogen fixation. In particular, we have shown Hfq interactions with various regulatory proteins' mRNA and their potential targets at the posttranscriptional level. This study not only enhances our understanding of Hfq regulation but, importantly, also provides a framework for addressing integrated regulatory network underlying root-associated nitrogen fixation.


Assuntos
Regulação Bacteriana da Expressão Gênica , Fator Proteico 1 do Hospedeiro , Fixação de Nitrogênio , Raízes de Plantas , Pseudomonas stutzeri , Pseudomonas stutzeri/genética , Pseudomonas stutzeri/metabolismo , Fator Proteico 1 do Hospedeiro/genética , Fator Proteico 1 do Hospedeiro/metabolismo , Fixação de Nitrogênio/genética , Raízes de Plantas/microbiologia , RNA Bacteriano/genética , RNA Bacteriano/metabolismo , Perfilação da Expressão Gênica , Redes Reguladoras de Genes , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala , Transcriptoma , Rizosfera
16.
Adv Healthc Mater ; 12(6): e2202652, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36373219

RESUMO

The rising dangers of bacterial infections have created an urgent need for the development of a new generation of antibacterial technologies and therapeutics. Antibacterial photodynamic therapy (PDT), considered as a noninvasive treatment with no drug resistance, has become a new promising photochemistry-involved treatment strategy. Titanium oxide (TiO2 ) is proved to be a very efficient PDT agent among the photosensitive materials, while the property of a large bandgap of TiO2 makes it only be excited by ultraviolet light, which is harmful to organisms. In this work, a novel ligand-to-metal charge transfer (LMCT) mediated TiO2 PDT strategy is proposed via the harmless near-infrared light irradiation. By choosing a mussel-inspired material, polydopamine (PDA) is involved in forming mesoporous TiO2 @PDA nanoparticles (mTiO2 @PDA NPs). The catechol groups of PDA can attach the TiO2 tightly even in colloidal environments, and can also form the LMCT bridge, exciting TiO2 to exert PDT function via 808 nm irradiation. Combining the sonodynamic therapy (SDT) of TiO2 and the photothermal therapy properties of PDA, this simple structure mTiO2 @PDA enables synergistic antibacterial applications with multiple functions under the dual excitation of NIR and ultrasound. This reliable all-in-one NPs can achieve great antibacterial effect and a rapid repair of infected wounds.


Assuntos
Nanocompostos , Fotoquimioterapia , Bactérias , Antibacterianos/farmacologia , Antibacterianos/química , Nanocompostos/uso terapêutico , Nanocompostos/química , Cicatrização
17.
J Nutr Biochem ; 117: 109351, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37087074

RESUMO

Resveratrol (RES) is one of the best-known bioactive polyphenols that has received much attention in recent years because of its importance to anti-obesity. However, the exact mechanism underlying this effect and whether it can improve lipid metabolism by regulating the long-chain noncoding RNA (lncRNA) remains unclear. In this study, 24 healthy crossbred castrated boars were fed a basal diet (control) and a basal diet supplemented with 200 mg, 400 mg or 600 mg RES per Kilogram (kg) of feed for 41 d, respectively. We found that 400 mg/kg and 600 mg/kg RES-supplemented diet did not affect growth rate, but reduced significantly subcutaneous adipose thickness, carcass fat rate, greater dramatically the serum concentration of adiponectin and high-density lipoprotein in pigs. Further, we verified that RES could inhibit the formation and accumulation of lipid droplets by AdipoQ-AdipoR1-AMPKα and AdipoQ-AdipoR2-PPARα signal pathway in vivo and vitro (3T3-L1 preadipocytes). Transcriptome analyses found that 5 differently expressed (DE) lncRNAs and 77 mRNAs in subcutaneous adipose between control group and 400 mg/kg RES group, which mainly involved in "adipocytokine signaling pathway," "Wnt signaling pathway," "PI3K-Akt signaling pathway" and "MAPK signaling pathway." In conclusion, RES can inhibit the formation and accumulation of lipid droplets through AdipoQ signal pathway and lipid metabolism-related lncRNAs. Our results provide a new insight on the molecular mechanism of RES as a nutritional agents to the prevention and treatment for obesity.


Assuntos
Metabolismo dos Lipídeos , RNA Longo não Codificante , Masculino , Animais , Suínos , Metabolismo dos Lipídeos/genética , RNA Longo não Codificante/genética , Resveratrol/farmacologia , Gotículas Lipídicas/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Obesidade/metabolismo , Transdução de Sinais
18.
Genes (Basel) ; 14(2)2023 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-36833242

RESUMO

MicroRNAs (miRNAs) are small non-coding RNAs that post-transcriptionally regulate several pathway intermediates and affect the skeletal muscle development in mice, pigs, sheep, and cattle. However, to date, only a small number of miRNAs have been reported in the muscle development of goats. In this report, the longissimus dorsi transcripts of one- and ten-month-old goats were analyzed by sequencing RNAs and miRNAs. The results showed that the ten-month-old Longlin goats had 327 up- and 419 down-regulated differentially expressed genes (DEGs) compared with the one-month-old. In addition, 20 co-up-regulated and 55 co-down-regulated miRNAs involved in the muscle fiber hypertrophy of goats were identified in ten-month-old Longlin and Nubian goats compared with one-month-old. Five miRNA-mRNA pairs (chi-let-7b-3p-MIRLET7A, chi-miR193b-3p-MMP14, chi-miR-355-5p-DGAT2, novel_128-LOC102178119, novel_140-SOD3) involved in the goat skeletal muscle development were identified by miRNA-mRNA negative correlation network analysis. Our results provided new insight into the functional roles of goat muscle-associated miRNAs, allowing a deeper understanding of the transformation of miRNA roles during mammalian muscle development.


Assuntos
MicroRNAs , Suínos , Animais , Bovinos , Camundongos , Ovinos/genética , MicroRNAs/genética , Perfilação da Expressão Gênica , RNA Mensageiro/genética , Cabras/genética , Fibras Musculares Esqueléticas/metabolismo , Hipertrofia
19.
Clin Cancer Res ; 29(2): 472-487, 2023 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-36322002

RESUMO

PURPOSE: PAX-fusion negative rhabdomyosarcoma (FN RMS) is driven by alterations in the RAS/MAP kinase pathway and is partially responsive to MEK inhibition. Overexpression of IGF1R and its ligands is also observed in FN RMS. Preclinical and clinical studies have suggested that IGF1R is itself an important target in FN RMS. Our previous studies revealed preclinical efficacy of the MEK1/2 inhibitor, trametinib, and an IGF1R inhibitor, BMS-754807, but this combination was not pursued clinically due to intolerability in preclinical murine models. Here, we sought to identify a combination of an MEK1/2 inhibitor and IGF1R inhibitor, which would be tolerated in murine models and effective in both cell line and patient-derived xenograft models of RAS-mutant FN RMS. EXPERIMENTAL DESIGN: Using proliferation and apoptosis assays, we studied the factorial effects of trametinib and ganitumab (AMG 479), a mAb with specificity for human and murine IGF1R, in a panel of RAS-mutant FN RMS cell lines. The molecular mechanism of the observed synergy was determined using conventional and capillary immunoassays. The efficacy and tolerability of trametinib/ganitumab was assessed using a panel of RAS-mutated cell-line and patient-derived RMS xenograft models. RESULTS: Treatment with trametinib and ganitumab resulted in synergistic cellular growth inhibition in all cell lines tested and inhibition of tumor growth in four of six models of RAS-mutant RMS. The combination had little effect on body weight and did not produce thrombocytopenia, neutropenia, or hyperinsulinemia in tumor-bearing SCID beige mice. Mechanistically, ganitumab treatment prevented the phosphorylation of AKT induced by MEK inhibition alone. Therapeutic response to the combination was observed in models without a mutation in the PI3K/PTEN axis. CONCLUSIONS: We demonstrate that combined trametinib and ganitumab is effective in a genomically diverse panel of RAS-mutated FN RMS preclinical models. Our data also show that the trametinib/ganitumab combination likely has a favorable tolerability profile. These data support testing this combination in a phase I/II clinical trial for pediatric patients with relapsed or refractory RAS-mutated FN RMS.


Assuntos
Rabdomiossarcoma , Humanos , Animais , Camundongos , Criança , Linhagem Celular Tumoral , Camundongos SCID , Rabdomiossarcoma/tratamento farmacológico , Rabdomiossarcoma/genética , Rabdomiossarcoma/patologia , Inibidores de Proteínas Quinases/farmacologia , Quinases de Proteína Quinase Ativadas por Mitógeno
20.
Cell Death Discov ; 8(1): 53, 2022 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-35136045

RESUMO

N6-Methyladenosine (m6A) modification is the most abundant RNA modification in eukaryotic cells. IGF2BP3, a well-known m6A reader, is deregulated in many cancers, but its role in nasopharyngeal carcinoma (NPC) remains unclear. In this work, IGF2BP3 was upregulated in NPC tissues and cells. The high level of IGF2BP3 was positively related to late clinical stages, node metastasis, and poor outcomes. Moreover, IGF2BP3 accelerated NPC cell tumor progression and metastasis in vitro and vivo. Upstream mechanism analyses indicated that the high expression of IGF2BP3 in head and neck tumors was mainly due to mRNA level amplification. Luciferase assay and chromatin immunoprecipitation assay (CHIP) depicted that MYC was effectively bound to the promoter of IGF2BP3, thereby improving its transcriptional activity. Results also showed that IGF2BP3 was not only positively correlated with KPNA2 expression but also modulated the expression of KPNA2. m6A RNA immunoprecipitation (MeRIP) and RNA stability experiments verified that silencing IGF2BP3 significantly inhibited the m6A modification level of KPNA2, thereby stabilizing the mRNA stability of KPNA2. Rescue experiments proved that the effect of inhibiting or overexpressing IGF2BP3 on NPC cells was partly reversed by KPNA2. Collectively, MYC-activated IGF2BP3 promoted NPC cell proliferation and metastasis by influencing the stability of m6A-modified KPNA2. Our findings offer new insights that IGF2BP3 may serve as a new molecular marker and potential therapeutic target for NPC treatment.

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