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1.
BMC Oral Health ; 24(1): 341, 2024 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-38493083

RESUMO

BACKGROUND: Oral squamous carcinoma (OSCC) is often diagnosed at late stages and bone erosion or invasion of the jawbone is frequently present. Computed tomography (CT) and magnetic resonance imaging (MRI) are known to have high diagnostic sensitivities, specificities, and accuracies in detecting these bone affections in patients suffering from OSCC. To date, the existing data regarding the impact of cone-beam computed tomography (CBCT) have been weak. Therefore, this study aimed to investigate whether CBCT is a suitable tool to detect bone erosion or invasion in patients with OSCC. METHODS: We investigated in a prospective trial the impact of CBCT in the diagnosis of bone erosion or invasion in patients with OSCC who underwent surgery. Every participant received a CBCT, CT, and MRI scan during staging. Imaging modalities were evaluated by two specialists in oral and maxillofacial surgery (CBCT) and two specialists in radiology (CT and MRI) in a blinded way, to determine whether a bone affection was present or not. Reporting used the following 3-point system: no bony destruction ("0"), cortical bone erosion ("1"), or medullary bone invasion ("2"). Histological examination or a follow-up served to calculate the sensitivities, specificities, and accuracies of the imaging modalities. RESULTS: Our results revealed high diagnostic sensitivities (95.6%, 84.4%, and 88.9%), specificities (87.0%, 91.7%, and 91.7%), and accuracies (89.5%, 89.5%, and 90.8%) for CBCT, CT, and MRI. A pairwise comparison found no statistical difference between CBCT, CT, and MRI. CONCLUSION: Our data support the routine use of CBCT in the diagnosis of bone erosion and invasion in patients with OSCC as diagnostic accuracy is equal to CT and MRI, the procedure is cost-effective, and it can be performed during initial contact with the patient.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Bucais , Tomografia Computadorizada de Feixe Cônico Espiral , Humanos , Carcinoma de Células Escamosas/diagnóstico por imagem , Carcinoma de Células Escamosas/patologia , Tomografia Computadorizada de Feixe Cônico , Células Epiteliais , Imageamento por Ressonância Magnética , Neoplasias Bucais/diagnóstico por imagem , Neoplasias Bucais/patologia , Estudos Prospectivos , Carcinoma de Células Escamosas de Cabeça e Pescoço , Tomografia Computadorizada por Raios X
2.
J Am Chem Soc ; 145(28): 15094-15108, 2023 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-37401816

RESUMO

Pharmacological modulation of cannabinoid receptor type 2 (CB2R) holds promise for the treatment of neuroinflammatory disorders, such as Alzheimer's disease. Despite the importance of CB2R, its expression and downstream signaling are insufficiently understood in disease- and tissue-specific contexts. Herein, we report the first ligand-directed covalent (LDC) labeling of CB2R enabled by a novel synthetic strategy and application of platform reagents. The LDC modification allows visualization and study of CB2R while maintaining its ability to bind other ligands at the orthosteric site. We employed in silico docking and molecular dynamics simulations to guide probe design and assess the feasibility of LDC labeling of CB2R. We demonstrate selective, covalent labeling of a peripheral lysine residue of CB2R by exploiting fluorogenic O-nitrobenzoxadiazole (O-NBD)-functionalized probes in a TR-FRET assay. The rapid proof-of-concept validation with O-NBD probes inspired incorporation of advanced electrophiles suitable for experiments in live cells. To this end, novel synthetic strategies toward N-sulfonyl pyridone (N-SP) and N-acyl-N-alkyl sulfonamide (NASA) LDC probes were developed, which allowed covalent delivery of fluorophores suitable for cellular studies. The LDC probes were characterized by a radioligand binding assay and TR-FRET experiments. Additionally, the probes were applied to specifically visualize CB2R in conventional and imaging flow cytometry as well as in confocal fluorescence microscopy using overexpressing and endogenously expressing microglial live cells.


Assuntos
Corantes Fluorescentes , Transdução de Sinais , Ligantes , Ligação Proteica , Corantes Fluorescentes/química , Receptores de Canabinoides
3.
J Am Chem Soc ; 145(40): 21937-21944, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37767920

RESUMO

Targeted protein degradation relies on small molecules that induce new protein-protein interactions between targets and the cellular protein degradation machinery. Most of these small molecules feature specific ligands for ubiquitin ligases. Recently, the attachment of cysteine-reactive chemical groups to pre-existing small molecule inhibitors has been shown to drive specific target degradation. We demonstrate here that different cysteine-reactive groups can specify target degradation via distinct ubiquitin ligases. By focusing on the bromodomain ligand JQ1, we identify cysteine-reactive functional groups that drive BRD4 degradation by either DCAF16 or DCAF11. Unlike proteolysis-targeting chimeric molecules (PROTACs), the new compounds use a single small molecule ligand with a well-positioned cysteine-reactive group to induce protein degradation. The finding that nearly identical compounds can engage multiple ubiquitination pathways suggests that targeting cellular pathways that search for and eliminate chemically reactive proteins is a feasible avenue for converting existing small molecule drugs into protein degrader molecules.

4.
Clin Oral Investig ; 27(10): 5991-5998, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37603167

RESUMO

OBJECTIVES: Different platelet-rich fibrin (PRF) protocols exist and are known to differ in resulting mechanical and bioactive properties. Centrifugation parameters may also influence drug release, in particular antibiotics, when using PRF as a bio-carrier. We thus evaluated three common protocols regarding effects on the bio-carrier properties. MATERIALS AND METHODS: In a prospective trial comprising 33 patients, we compared different protocols for PRF as a bio-carrier for ampicillin/sulbactam (SAM). Blood samples were taken shortly after a single dose of ampicillin/sulbactam (2 g/1 g) was administered to patients intravenously. PRF was obtained by centrifugation and three protocols were used: protocol A (1300 rpm, 8 min, RCF-max = 208 g), B (2300 rpm, 12 min, RCF-max = 652 g), and C (1500 rpm, 14 min, RCF-max = 276 g). The antibacterial activity of PRF was investigated against five oral species in vitro, based on agar diffusion methodology. RESULTS: The study demonstrates that a single dose of SAM is sufficient to reach high concentrations in PRF in all protocols (150 µg/ml), which is comparable to the plasma SAM concentration. Antibacterial activity was inferred from the diameter of inhibition zones seen in agar diffusion tests using PRF discs. Protocol B resulted in the largest inhibition zones. One-way ANOVA revealed statistically improved results for protocol B for some bacteria. CONCLUSIONS: The study provides valuable data on PRF antibiotic enrichment, notably SAM. A single dose of SAM is sufficient to reach clinically relevant concentrations in PRF. CLINICAL RELEVANCE: These findings potentially extend the application of PRF, for example in patients with osteonecrosis of the jaw or in oral surgery (e.g., stick bone).


Assuntos
Fibrina Rica em Plaquetas , Humanos , Sulbactam/farmacologia , Ágar , Estudos Prospectivos , Peptídeos e Proteínas de Sinalização Intercelular , Centrifugação/métodos , Antibacterianos/farmacologia , Ampicilina/farmacologia
5.
J Shoulder Elbow Surg ; 32(6): 1262-1270, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36914048

RESUMO

PURPOSE: To evaluate midterm outcome of lateral ulnar collateral ligament (LUCL) repair with triceps autograft in patients with PLRI under recalcitrant lateral epicondylitis. METHODS: In total, 25 elbows (23 patients) with recalcitrant epicondylitis longer than 12 months were included into this retrospective study. All patients underwent arthroscopic instability examination. In 18 elbows (16 patients, mean age 47.4 years, range 25-60), PLRI was verified, and an LUCL repair using an autologous triceps tendon graft was performed. Clinical outcome was evaluated before and at least 3 years after surgery using the American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form-Elbow Score (ASES-E), Liverpool Elbow Score (LES), Mayo Elbow Performance Index (MEPI), Patient-Rated Elbow Evaluation score (PREE), Subjective Elbow Value (SEV), quick Disabilities of the Arm, Shoulder, and Hand score (qDASH), and the visual analog scale (VAS) for pain. Postoperative satisfaction with the procedure and complications were recorded. RESULTS: Seventeen patients were available at a mean follow-up of 66.4 months (range 48-81). Patient satisfaction postoperatively was reported in 15 elbows as excellent (90%-100%) and 2 as moderate, with 93.1% overall. All scores of the 3 female and 12 male patients significantly increased from pre- to the postoperative follow-up (ASES: 28.3 ± 10.7 to 54.6 ± 12.1, P < .001; MEPI: 49.2 ± 8.3 to 90.5 ± 15.4, P < .001; PREE: 66.1 ± 14.9 to 11.3 ± 23.5, P < .001; qDASH: 63.2 ± 21.1 to 11.5 ± 22.6, P < .001; VAS: 8.75 ± 1.0 to 1.5 ± 2.0, P < .001). All patients suffered from high extension pain preoperatively, which was reported to be relieved after surgery. No recurrent instability or major complication occurred. CONCLUSION: The repair and augmentation of the LUCL with a triceps tendon autograft reached significant improvements; hence, it seems to be a good treatment option for posterolateral elbow rotatory instability with promising midterm results under a low rate of recurrent instability.


Assuntos
Ligamento Colateral Ulnar , Ligamentos Colaterais , Articulação do Cotovelo , Instabilidade Articular , Cotovelo de Tenista , Reconstrução do Ligamento Colateral Ulnar , Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Reconstrução do Ligamento Colateral Ulnar/efeitos adversos , Cotovelo de Tenista/cirurgia , Cotovelo de Tenista/complicações , Braço/cirurgia , Autoenxertos , Estudos Retrospectivos , Ligamento Colateral Ulnar/cirurgia , Tendões/transplante , Articulação do Cotovelo/cirurgia , Instabilidade Articular/etiologia , Ligamentos Colaterais/cirurgia
6.
Actas Dermosifiliogr ; 114(4): 291-298, 2023 Apr.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-36529273

RESUMO

BACKGROUND AND OBJECTIVE: Primary cutaneous lymphomas (PCL) are uncommon. Observations based on the first year of data from the Spanish Registry of Primary Cutaneous Lymphomas (RELCP, in its Spanish abbreviation) of the Spanish Academy of Dermatology and Venereology (AEDV) were published in February 2018. This report covers RELCP data for the first 5 years. PATIENTS AND METHODS: RELCP data were collected prospectively and included diagnosis, treatments, tests, and the current status of patients. We compiled descriptive statistics of the data registered during the first 5 years. RESULTS: Information on 2020 patients treated at 33 Spanish hospitals had been included in the RELCP by December 2021. Fifty-nine percent of the patients were men; the mean age was 62.2 years. The lymphomas were grouped into 4 large diagnostic categories: mycosis fungoides/Sézary syndrome, 1112 patients (55%); primary B-cell cutaneous lymphoma, 547 patients (27.1%); primary CD30+lymphoproliferative disorders, 222 patients (11%), and other T-cell lymphomas, 116 patients (5.8%). Nearly 75% of the tumors were registered in stage I. After treatment, 43.5% achieved complete remission and 27% were stable at the time of writing. Treatments prescribed were topical corticosteroids (1369 [67.8%]), phototherapy (890 patients [44.1%]), surgery (412 patients [20.4%]), and radiotherapy (384 patients [19%]). CONCLUSION: The characteristics of cutaneous lymphomas in Spain are similar to those reported for other series. The large size of the RELCP registry at 5 years has allowed us to give more precise descriptive statistics than in the first year. This registry facilitates the clinical research of the AEDV's lymphoma interest group, which has already published articles based on the RELCP data.


Assuntos
Dermatologia , Linfoma Cutâneo de Células T , Micose Fungoide , Neoplasias Cutâneas , Venereologia , Masculino , Humanos , Pessoa de Meia-Idade , Feminino , Linfoma Cutâneo de Células T/diagnóstico , Linfoma Cutâneo de Células T/epidemiologia , Linfoma Cutâneo de Células T/terapia , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/epidemiologia , Neoplasias Cutâneas/terapia , Sistema de Registros , Micose Fungoide/patologia
7.
Bioconjug Chem ; 33(6): 1210-1221, 2022 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-35658441

RESUMO

Inhibition of intracellular nicotinamide phosphoribosyltransferase (NAMPT) represents a new mode of action for cancer-targeting antibody-drug conjugates (ADCs) with activity also in slowly proliferating cells. To extend the repertoire of available effector chemistries, we have developed a novel structural class of NAMPT inhibitors as ADC payloads. A structure-activity relationship-driven approach supported by protein structural information was pursued to identify a suitable attachment point for the linker to connect the NAMPT inhibitor with the antibody. Optimization of scaffolds and linker structures led to highly potent effector chemistries which were conjugated to antibodies targeting C4.4a (LYPD3), HER2 (c-erbB2), or B7H3 (CD276) and tested on antigen-positive and -negative cancer cell lines. Pharmacokinetic studies, including metabolite profiling, were performed to optimize the stability and selectivity of the ADCs and to evaluate potential bystander effects. Optimized NAMPTi-ADCs demonstrated potent in vivo antitumor efficacy in target antigen-expressing xenograft mouse models. This led to the development of highly potent NAMPT inhibitor ADCs with a very good selectivity profile compared with the corresponding isotype control ADCs. Moreover, we demonstrate─to our knowledge for the first time─the generation of NAMPTi payload metabolites from the NAMPTi-ADCs in vitro and in vivo. In conclusion, NAMPTi-ADCs represent an attractive new payload class designed for use in ADCs for the treatment of solid and hematological cancers.


Assuntos
Antineoplásicos , Imunoconjugados , Neoplasias , Nicotinamida Fosforribosiltransferase , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Antígenos B7 , Linhagem Celular Tumoral , Humanos , Imunoconjugados/química , Imunoconjugados/farmacologia , Camundongos , Neoplasias/tratamento farmacológico , Neoplasias/enzimologia , Nicotinamida Fosforribosiltransferase/antagonistas & inibidores , Nicotinamida Fosforribosiltransferase/química , Relação Estrutura-Atividade , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Nat Chem Biol ; 16(5): 497-506, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32231343

RESUMO

We recently described glutathione peroxidase 4 (GPX4) as a promising target for killing therapy-resistant cancer cells via ferroptosis. The onset of therapy resistance by multiple types of treatment results in a stable cell state marked by high levels of polyunsaturated lipids and an acquired dependency on GPX4. Unfortunately, all existing inhibitors of GPX4 act covalently via a reactive alkyl chloride moiety that confers poor selectivity and pharmacokinetic properties. Here, we report our discovery that masked nitrile-oxide electrophiles, which have not been explored previously as covalent cellular probes, undergo remarkable chemical transformations in cells and provide an effective strategy for selective targeting of GPX4. The new GPX4-inhibiting compounds we describe exhibit unexpected proteome-wide selectivity and, in some instances, vastly improved physiochemical and pharmacokinetic properties compared to existing chloroacetamide-based GPX4 inhibitors. These features make them superior tool compounds for biological interrogation of ferroptosis and constitute starting points for development of improved inhibitors of GPX4.


Assuntos
Inibidores Enzimáticos/farmacologia , Nitrilas/química , Nitrilas/farmacologia , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/antagonistas & inibidores , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/metabolismo , Animais , Linhagem Celular Tumoral , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacocinética , Ferroptose/efeitos dos fármacos , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Camundongos SCID , Sondas Moleculares/química , Terapia de Alvo Molecular , Óxidos/química , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/química , Pró-Fármacos/química , Ratos Wistar , Selenocisteína/química , Selenocisteína/metabolismo , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologia , Relação Estrutura-Atividade
9.
BMC Pregnancy Childbirth ; 22(1): 253, 2022 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-35346075

RESUMO

BACKGROUND: Physical activity (PA) interventions are an important but underutilised component in the management of gestational diabetes mellitus (GDM). The challenge remains how to deliver cost effective PA interventions that have impact on individual behaviour. Digital technologies can support and promote PA remotely at scale. We describe the development of a behaviourally informed smartphone application (Stay-Active) for women attending an NHS GDM clinic. Stay-Active will support an existing motivational interviewing intervention to increase and maintain PA in this population. METHODS: The behaviour change wheel (BCW) eight step theoretical approach was used to design the application. It provided a systematic approach to understanding the target behaviour, identifying relevant intervention functions, and specifying intervention content. The target behaviour was to increase and maintain PA. To obtain a behavioural diagnosis, qualitative evidence was combined with focus groups on the barriers and facilitators to PA in women with GDM. The findings were mapped onto the Capability Opportunity Motivation-Behaviour (COM-B) model and Theoretical Domains Framework to identify what needs to change for the target behaviour and linked to appropriate intervention functions. Finally, behaviour changes techniques (BCT) and modes of delivery that are most likely to serve the intervention functions were selected. Current evidence, patient focus groups and input from key stakeholders informed Stay-Active's development. RESULTS: We found that psychological capability, reflective and automatic motivation, social and physical opportunity needed to change to increase PA in women with GDM. The four key intervention functions identified were Enablement, Education, Persuasion and Training. Stay-Active incorporates these four intervention functions delivering ten BCTs including: goal setting, credible source, self-monitoring, action planning, prompts and cues. The final design of Stay-Active delivers these BCTs via an educational resource centre, with goal setting and action planning features, personalised performance feedback and individualised promotional messages. CONCLUSION: The BCW has enabled the systematic and comprehensive development of Stay-Active to promote PA in women with GDM within an NHS Maternity service. The next phase is to conduct a trial to assess the feasibility and acceptability of a multi-component intervention that combines Stay-Active with PA Motivational Interviewing.


Assuntos
Diabetes Gestacional , Terapia Comportamental/métodos , Diabetes Gestacional/terapia , Exercício Físico/psicologia , Feminino , Humanos , Motivação , Gravidez , Smartphone
10.
Proc Natl Acad Sci U S A ; 116(7): 2551-2560, 2019 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-30683722

RESUMO

Since the late 1980s, mutations in the RAS genes have been recognized as major oncogenes with a high occurrence rate in human cancers. Such mutations reduce the ability of the small GTPase RAS to hydrolyze GTP, keeping this molecular switch in a constitutively active GTP-bound form that drives, unchecked, oncogenic downstream signaling. One strategy to reduce the levels of active RAS is to target guanine nucleotide exchange factors, which allow RAS to cycle from the inactive GDP-bound state to the active GTP-bound form. Here, we describe the identification of potent and cell-active small-molecule inhibitors which efficiently disrupt the interaction between KRAS and its exchange factor SOS1, a mode of action confirmed by a series of biophysical techniques. The binding sites, mode of action, and selectivity were elucidated using crystal structures of KRASG12C-SOS1, SOS1, and SOS2. By preventing formation of the KRAS-SOS1 complex, these inhibitors block reloading of KRAS with GTP, leading to antiproliferative activity. The final compound 23 (BAY-293) selectively inhibits the KRAS-SOS1 interaction with an IC50 of 21 nM and is a valuable chemical probe for future investigations.


Assuntos
Proteínas Proto-Oncogênicas p21(ras)/antagonistas & inibidores , Proteína SOS1/antagonistas & inibidores , Linhagem Celular , Cristalografia por Raios X , Descoberta de Drogas , Transferência Ressonante de Energia de Fluorescência , Ensaios de Triagem em Larga Escala , Humanos , Ligação Proteica , Proteínas Proto-Oncogênicas p21(ras)/química , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Proteína SOS1/química , Proteína SOS1/metabolismo , Transdução de Sinais
11.
Clin Oral Investig ; 26(12): 7033-7044, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35941396

RESUMO

OBJECTIVES: Mechanisms of wound healing are often impaired in patients with osteonecrosis of the jaw (ONJ). According to the guidelines for the treatment of this disease, early surgical intervention is indicated. However, surgery often faces complications such as wound healing disorders. The application of platelet-rich fibrin (PRF) after necrosectomy between bone and mucosa may constitute a promising approach to improve surgical results. An aspect that was not investigated until now is that PRF acts as a "bio-carrier" for antibiotics previously applied intravenously. MATERIALS AND METHODS: We investigated the antimicrobial properties of PRF in 24 patients presenting ONJ undergoing systemic antibiosis with ampicillin/sulbactam. We measured the concentration of ampicillin/sulbactam in plasma and PRF and performed agar diffusion tests. Ampicillin/sulbactam was applied intravenously to the patient 10 minutes for blood sampling for PRF. No further incorporation of patients' blood or PRF product with antibiotic drugs was obtained. Four healthy patients served as controls. RESULTS: Our results revealed that PRF is highly enriched with ampicillin/sulbactam that is released to the environment. The antibiotic concentration in PRF was comparable to the plasma concentration of ampicillin/sulbactam. The inhibition zone (IZ) of PRF was comparable to the standard ampicillin/sulbactam discs used in sensitivity testing. CONCLUSIONS: The results of our study demonstrated that PRF is a reliable bio-carrier for systemic applied antibiotics and exhibits a large antimicrobial effect. CLINICAL RELEVANCE: We describe a clinically useful feature of PRF as a bio-carrier for antibiotics. Especially when applied to poorly perfused tissues and bone such as in ONJ, the local release of antibiotics can reduce wound healing disorders like infections.


Assuntos
Fibrina Rica em Plaquetas , Humanos , Sulbactam/farmacologia , Ampicilina/farmacologia , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico
12.
Int J Mol Sci ; 23(2)2022 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-35054968

RESUMO

The enzyme pyruvate kinase M2 (PKM2) plays a major role in the switch of tumor cells from oxidative phosphorylation to aerobic glycolysis, one of the hallmarks of cancer. Different allosteric inhibitors or activators and several posttranslational modifications regulate its activity. Head and neck squamous cell carcinoma (HNSCC) is a common disease with a high rate of recurrence. To find out more about PKM2 and its modulation in HNSCC, we examined a panel of HNSCC cells using real-time cell metabolic analysis and Western blotting with an emphasis on phosphorylation variant Tyr105 and two reagents known to impair PKM2 activity. Our results show that in HNSCC, PKM2 is commonly phosphorylated at Tyrosine 105. Its levels depended on tyrosine kinase activity, emphasizing the importance of growth factors such as EGF (epidermal growth factor) on HNSCC metabolism. Furthermore, its correlation with the expression of CD44 indicates a role in cancer stemness. Cells generally reacted with higher glycolysis to PKM2 activator DASA-58 and lower glycolysis to PKM2 inhibitor Compound 3k, but some were more susceptible to activation and others to inhibition. Our findings emphasize the need to further investigate the role of PKM2 in HNSCC, as it could aid understanding and treatment of the disease.


Assuntos
Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/etiologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo , Hormônios Tireóideos/genética , Hormônios Tireóideos/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Biomarcadores , Linhagem Celular Tumoral , Suscetibilidade a Doenças , Relação Dose-Resposta a Droga , Descoberta de Drogas , Metabolismo Energético/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Variação Genética , Humanos , Fosforilação , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Proteínas de Ligação a Hormônio da Tireoide
13.
J Am Chem Soc ; 143(2): 736-743, 2021 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-33399457

RESUMO

Cannabinoid receptor 2 (CB2) is a promising target for the treatment of neuroinflammation and other diseases. However, a lack of understanding of its complex signaling in cells and tissues complicates the therapeutic exploitation of CB2 as a drug target. We show for the first time that benchmark CB2 agonist HU308 increases cytosolic Ca2+ levels in AtT-20(CB2) cells via CB2 and phospholipase C. The synthesis of photoswitchable derivatives of HU308 from the common building block 3-OTf-HU308 enables optical control over this pathway with spatiotemporal precision, as demonstrated in a real-time Ca2+ fluorescence assay. Our findings reveal a novel messenger pathway by which HU308 and its derivatives affect cellular excitability, and they demonstrate the utility of chemical photoswitches to control and monitor CB2 signaling in real-time.


Assuntos
Cálcio/metabolismo , Agonistas de Receptores de Canabinoides/farmacologia , Canabinoides/farmacologia , Receptor CB2 de Canabinoide/agonistas , Agonistas de Receptores de Canabinoides/síntese química , Agonistas de Receptores de Canabinoides/química , Canabinoides/síntese química , Canabinoides/química , Humanos , Estrutura Molecular , Processos Fotoquímicos
14.
Eur J Nucl Med Mol Imaging ; 48(12): 3951-3960, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34050405

RESUMO

PURPOSE: While [18F]-fluorodeoxyglucose ([18F]FDG) is the standard for positron emission tomography/computed tomography (PET/CT) imaging of oral squamous cell carcinoma (OSCC), diagnostic specificity is hampered by uptake in inflammatory cells such as neutrophils or macrophages. Recently, molecular imaging probes targeting fibroblast activation protein α (FAP), which is overexpressed in a variety of cancer-associated fibroblasts, have become available and might constitute a feasible alternative to FDG PET/CT. METHODS: Ten consecutive, treatment-naïve patients (8 males, 2 females; mean age, 62 ± 9 years) with biopsy-proven OSCC underwent both whole-body [18F]FDG and [68Ga]FAPI-04 (FAP-directed) PET/CT for primary staging prior to tumor resection and cervical lymph node dissection. Detection of the primary tumor, as well as the presence and number of lymph node and distant metastases was analysed. Intensity of tracer accumulation was assessed by means of maximum (SUVmax) and peak (SUVpeak) standardized uptake values. Histological work-up including immunohistochemical staining for FAP served as standard of reference. RESULTS: [18F]FDG and FAP-directed PET/CT detected all primary tumors with a SUVmax of 25.5 ± 13.2 (FDG) and 20.5 ± 6.4 (FAP-directed) and a SUVpeak of 16.1 ± 10.3 ([18F]FDG) and 13.8 ± 3.9 (FAP-directed), respectively. Regarding cervical lymph node metastases, FAP-directed PET/CT demonstrated comparable sensitivity (81.3% vs. 87.5%; P = 0.32) and specificity (93.3% vs. 81.3%; P = 0.16) to [18F]FDG PET/CT. FAP expression on the cell surface of cancer-associated fibroblasts in both primary lesions as well as lymph nodes metastases was confirmed in all samples. CONCLUSION: FAP-directed PET/CT in OSCC seems feasible. Future research to investigate its potential to improve patient staging is highly warranted.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Bucais , Idoso , Carcinoma de Células Escamosas/diagnóstico por imagem , Feminino , Fibroblastos , Fluordesoxiglucose F18 , Humanos , Linfonodos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/diagnóstico por imagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Tomografia por Emissão de Pósitrons , Quinolinas , Compostos Radiofarmacêuticos , Sensibilidade e Especificidade
15.
BJU Int ; 128(3): 352-360, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33706408

RESUMO

OBJECTIVE: To develop a new digital biomarker based on the analysis of primary tumour tissue by a convolutional neural network (CNN) to predict lymph node metastasis (LNM) in a cohort matched for already established risk factors. PATIENTS AND METHODS: Haematoxylin and eosin (H&E) stained primary tumour slides from 218 patients (102 N+; 116 N0), matched for Gleason score, tumour size, venous invasion, perineural invasion and age, who underwent radical prostatectomy were selected to train a CNN and evaluate its ability to predict LN status. RESULTS: With 10 models trained with the same data, a mean area under the receiver operating characteristic curve (AUROC) of 0.68 (95% confidence interval [CI] 0.678-0.682) and a mean balanced accuracy of 61.37% (95% CI 60.05-62.69%) was achieved. The mean sensitivity and specificity was 53.09% (95% CI 49.77-56.41%) and 69.65% (95% CI 68.21-71.1%), respectively. These results were confirmed via cross-validation. The probability score for LNM prediction was significantly higher on image sections from N+ samples (mean [SD] N+ probability score 0.58 [0.17] vs 0.47 [0.15] N0 probability score, P = 0.002). In multivariable analysis, the probability score of the CNN (odds ratio [OR] 1.04 per percentage probability, 95% CI 1.02-1.08; P = 0.04) and lymphovascular invasion (OR 11.73, 95% CI 3.96-35.7; P < 0.001) proved to be independent predictors for LNM. CONCLUSION: In our present study, CNN-based image analyses showed promising results as a potential novel low-cost method to extract relevant prognostic information directly from H&E histology to predict the LN status of patients with prostate cancer. Our ubiquitously available technique might contribute to an improved LN status prediction.


Assuntos
Aprendizado Profundo , Metástase Linfática , Redes Neurais de Computação , Neoplasias da Próstata/patologia , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Prognóstico , Estudos Retrospectivos
16.
J Med Internet Res ; 23(3): e21695, 2021 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-33764307

RESUMO

BACKGROUND: Studies have shown that artificial intelligence achieves similar or better performance than dermatologists in specific dermoscopic image classification tasks. However, artificial intelligence is susceptible to the influence of confounding factors within images (eg, skin markings), which can lead to false diagnoses of cancerous skin lesions. Image segmentation can remove lesion-adjacent confounding factors but greatly change the image representation. OBJECTIVE: The aim of this study was to compare the performance of 2 image classification workflows where images were either segmented or left unprocessed before the subsequent training and evaluation of a binary skin lesion classifier. METHODS: Separate binary skin lesion classifiers (nevus vs melanoma) were trained and evaluated on segmented and unsegmented dermoscopic images. For a more informative result, separate classifiers were trained on 2 distinct training data sets (human against machine [HAM] and International Skin Imaging Collaboration [ISIC]). Each training run was repeated 5 times. The mean performance of the 5 runs was evaluated on a multi-source test set (n=688) consisting of a holdout and an external component. RESULTS: Our findings showed that when trained on HAM, the segmented classifiers showed a higher overall balanced accuracy (75.6% [SD 1.1%]) than the unsegmented classifiers (66.7% [SD 3.2%]), which was significant in 4 out of 5 runs (P<.001). The overall balanced accuracy was numerically higher for the unsegmented ISIC classifiers (78.3% [SD 1.8%]) than for the segmented ISIC classifiers (77.4% [SD 1.5%]), which was significantly different in 1 out of 5 runs (P=.004). CONCLUSIONS: Image segmentation does not result in overall performance decrease but it causes the beneficial removal of lesion-adjacent confounding factors. Thus, it is a viable option to address the negative impact that confounding factors have on deep learning models in dermatology. However, the segmentation step might introduce new pitfalls, which require further investigations.


Assuntos
Melanoma , Neoplasias Cutâneas , Algoritmos , Inteligência Artificial , Dermoscopia , Humanos , Redes Neurais de Computação , Neoplasias Cutâneas/diagnóstico por imagem
17.
J Med Internet Res ; 23(7): e20708, 2021 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-34255646

RESUMO

BACKGROUND: Recent years have been witnessing a substantial improvement in the accuracy of skin cancer classification using convolutional neural networks (CNNs). CNNs perform on par with or better than dermatologists with respect to the classification tasks of single images. However, in clinical practice, dermatologists also use other patient data beyond the visual aspects present in a digitized image, further increasing their diagnostic accuracy. Several pilot studies have recently investigated the effects of integrating different subtypes of patient data into CNN-based skin cancer classifiers. OBJECTIVE: This systematic review focuses on the current research investigating the impact of merging information from image features and patient data on the performance of CNN-based skin cancer image classification. This study aims to explore the potential in this field of research by evaluating the types of patient data used, the ways in which the nonimage data are encoded and merged with the image features, and the impact of the integration on the classifier performance. METHODS: Google Scholar, PubMed, MEDLINE, and ScienceDirect were screened for peer-reviewed studies published in English that dealt with the integration of patient data within a CNN-based skin cancer classification. The search terms skin cancer classification, convolutional neural network(s), deep learning, lesions, melanoma, metadata, clinical information, and patient data were combined. RESULTS: A total of 11 publications fulfilled the inclusion criteria. All of them reported an overall improvement in different skin lesion classification tasks with patient data integration. The most commonly used patient data were age, sex, and lesion location. The patient data were mostly one-hot encoded. There were differences in the complexity that the encoded patient data were processed with regarding deep learning methods before and after fusing them with the image features for a combined classifier. CONCLUSIONS: This study indicates the potential benefits of integrating patient data into CNN-based diagnostic algorithms. However, how exactly the individual patient data enhance classification performance, especially in the case of multiclass classification problems, is still unclear. Moreover, a substantial fraction of patient data used by dermatologists remains to be analyzed in the context of CNN-based skin cancer classification. Further exploratory analyses in this promising field may optimize patient data integration into CNN-based skin cancer diagnostics for patients' benefits.


Assuntos
Melanoma , Neoplasias Cutâneas , Dermoscopia , Humanos , Melanoma/diagnóstico , Redes Neurais de Computação , Neoplasias Cutâneas/diagnóstico
18.
J Am Chem Soc ; 142(40): 16953-16964, 2020 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-32902974

RESUMO

Pharmacological modulation of cannabinoid type 2 receptor (CB2R) holds promise for the treatment of numerous conditions, including inflammatory diseases, autoimmune disorders, pain, and cancer. Despite the significance of this receptor, researchers lack reliable tools to address questions concerning the expression and complex mechanism of CB2R signaling, especially in cell-type and tissue-dependent contexts. Herein, we report for the first time a versatile ligand platform for the modular design of a collection of highly specific CB2R fluorescent probes, used successfully across applications, species, and cell types. These include flow cytometry of endogenously expressing cells, real-time confocal microscopy of mouse splenocytes and human macrophages, as well as FRET-based kinetic and equilibrium binding assays. High CB2R specificity was demonstrated by competition experiments in living cells expressing CB2R at native levels. The probes were effectively applied to FACS analysis of microglial cells derived from a mouse model relevant to Alzheimer's disease.


Assuntos
Doença de Alzheimer/metabolismo , Corantes Fluorescentes/química , Microglia/metabolismo , Receptor CB2 de Canabinoide/análise , Animais , Células CHO , Cricetulus , Modelos Animais de Doenças , Citometria de Fluxo , Transferência Ressonante de Energia de Fluorescência , Humanos , Ligantes , Camundongos , Simulação de Acoplamento Molecular , Sondas Moleculares/química , Imagem Óptica , Sensibilidade e Especificidade , Transdução de Sinais
19.
Chemistry ; 26(6): 1380-1387, 2020 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-31961047

RESUMO

The endocannabinoid (eCB) system is implied in various human diseases ranging from central nervous system to autoimmune disorders. Cannabinoid receptor 2 (CB2 R) is an integral component of the eCB system. Yet, the downstream effects elicited by this G protein-coupled receptor upon binding of endogenous or synthetic ligands are insufficiently understood-likely due to the limited arsenal of reliable biological and chemical tools. Herein, we report the design and synthesis of CB2 R-selective cannabinoids along with their in vitro pharmacological characterization (binding and functional studies). They combine structural features of HU-308 and AM841 to give chimeric ligands that emerge as potent CB2 R agonists with high selectivity over the closely related cannabinoid receptor 1 (CB1 R). The synthesis work includes convenient preparation of substituted resorcinols often found in cannabinoids. The utility of the synthetic cannabinoids in this study is showcased by preparation of the most selective high-affinity fluorescent probe for CB2 R to date.


Assuntos
Aminas/química , Canabinoides/química , Dronabinol/análogos & derivados , Receptor CB2 de Canabinoide/metabolismo , Sítios de Ligação , Canabinoides/metabolismo , Dronabinol/química , Dronabinol/metabolismo , Humanos , Cinética , Ligantes , Simulação de Acoplamento Molecular , Ligação Proteica , Estrutura Terciária de Proteína , Receptor CB1 de Canabinoide/química , Receptor CB1 de Canabinoide/metabolismo , Receptor CB2 de Canabinoide/química
20.
J Eur Acad Dermatol Venereol ; 34(4): 762-768, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31591786

RESUMO

BACKGROUND: Reliable prognostic factors for patients with primary cutaneous anaplastic large cell lymphoma (PCALCL) are lacking. OBJECTIVE: To identify prognostic factors for specific survival in patients with PCALCL. METHODS: Using the convenience sampling method, patients with PCALCL diagnosed from May 1986 to August 2017 in 16 University Departments were retrospectively reviewed. RESULTS: One hundred eight patients were included (57 males). Median age at diagnosis was 58 years. All of them showed T1-3N0M0 stages. Seventy per cent of the cases presented with a solitary lesion, mostly at the limbs. Complete response rate after first-line treatment was 87%, and no advantage was observed for any of them (surgery, radiotherapy, chemotherapy or other approaches). Nodal and visceral progression rate was 11% and 2%, respectively. 5-year specific survival (SSV) reached 93%; 97% for T1 patients and 84% for T2/T3 patients (P = 0.031). Five-year SSV for patients developing early cutaneous relapse was 64%; for those with late or no relapse, 96% (P = 0.001). Estimated median SSV for patients showing nodal progression was 103 months (95% CI: 51-155 months); for patients without nodal progression, estimated SSV did not reach the median (P < 0.001). Nodal progression was an independent predictive parameter for shorter survival (P = 0.011). CONCLUSION: Multiple cutaneous lesions at presentation, early skin relapse and nodal progression portrait worse prognosis in patients with PCALCL.


Assuntos
Linfoma Anaplásico Cutâneo Primário de Células Grandes/mortalidade , Linfoma Anaplásico Cutâneo Primário de Células Grandes/patologia , Progressão da Doença , Feminino , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Espanha , Taxa de Sobrevida
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