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1.
Cureus ; 15(7): e42091, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37602129

RESUMO

Many cases of adenopathies, whose differential diagnosis includes a wide spectrum of pathologies (including some malignant conditions like lymphoproliferative diseases, e.g., lymphomas), resort to primary healthcare. Kikuchi-Fujimoto disease is a rare, benign, self-limiting entity characterized by adenopathies, mainly in the cervical region, which may be associated with constitutional symptoms. This specific pathology is very rare in primary care and is often overlooked. That is why it is essential to promote medical literacy and provide support in managing these cases, which we want to emphasize through this case presentation. This case report presents a 24-year-old female patient who sought a consultation at the Family Health Unit due to a painful swelling in the right cervical region that lasted two weeks. She denied a history of recent infections or constitutional symptoms. A painful and hard right submaxillary mass, measuring 2 cm in diameter, was identified upon palpation. An analytical study and ultrasound of the soft tissues of the cervical region were initially required. Analytically, there were no relevant changes; however, the ultrasound revealed "hypoechoic ganglion formations in the right laterocervical chains, from the retroauricular region to the lower region of the neck, the largest measuring 19x7mm". The patient was reassessed one month later, due to an increase in the number of adenopathies, and a new ultrasound was performed that revealed "supraclavicular adenopathy". After that, she was referred to Secondary Healthcare (Central Hospital), where a lymph node biopsy was performed, with histological results of Kikuchi-Fujimoto disease. The patient maintains a follow-up in a hemato-oncology consultation, with painless adenopathies that, according to her, get worse with anxiety symptoms. Currently, the patient is being treated symptomatically, with stabilization of adenopathies and anxious manifestations. These patients need long-term follow-up due to the possibility of disease recurrence or the development of autoimmune processes. Although it is a diagnosis of exclusion, this disease must always be considered, since it can be mistaken with other serious pathologies that require aggressive treatments. Regarding the relationship between anxiety disorder and the worsening of adenopathies, although no conclusive evidence was found in the literature, there are some studies that have established a connection between inflammation and the deterioration of certain depressive symptoms.

2.
J Med Chem ; 64(21): 15758-15771, 2021 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-34546755

RESUMO

Rose bengal is an anionic dye considered as a potential photosensitizer for anticancer photodynamic therapy. The clinical utility of rose bengal is hampered by its short half-life, limited transmembrane transport, aggregation, and self-quenching; consequently, efficient drug carriers that overcome these obstacles are urgently required. In this study, we performed multilevel in vitro and in silico characterization of interactions between rose bengal and cationic poly(amidoamine) (PAMAM) and poly(propyleneimine) (PPI) dendrimers of the third and fourth generation and assessed the ability of the resultant complexes to modulate the photosensitizing properties of the drug. We focused on explaining the molecular basis of this phenomenon and proved that the generation- and structure-dependent binding of the dye by the dendrimers increases the cellular uptake and production of singlet oxygen and intracellular reactive oxygen species, leading to an increase in phototoxicity. We conclude that the application of dendrimer carriers could enable the design of efficient photodynamic therapies based on rose bengal.


Assuntos
Dendrímeros/química , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacologia , Polipropilenos/química , Rosa Bengala/farmacologia , Carcinoma Basocelular/metabolismo , Carcinoma Basocelular/patologia , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Fármacos Fotossensibilizantes/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Rosa Bengala/metabolismo , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia
3.
BMC Cancer ; 18(1): 217, 2018 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-29466962

RESUMO

BACKGROUND: MYCN is amplified in small cell lung cancers and several pediatric tumors, including alveolar rhabdomyosarcomas and neuroblastomas. MYCN protein is known to play a key oncogenic role in both alveolar rhabdomyosarcomas and neuroblastomas. MYCN opposite strand (MYCNOS) is a gene located on the antisense strand to MYCN that encodes alternatively spliced transcripts, two of which (MYCNOS-01 and MYCNOS-02) are known to be expressed in neuroblastoma and small cell lung cancer with reciprocal regulation between MYCNOS-02 and MYCN reported for neuroblastomas. We sought to determine a functional role for MYCNOS-01 in alveolar rhabdomyosarcoma and neuroblastoma cells and identify any associated regulatory effects between MYCN and MYCNOS-01. METHODS: MYCNOS-01, MYCNOS-02 and MYCN expression levels were assessed in alveolar rhabdomyosarcoma and neuroblastoma cell lines and tumor samples from patients using Affymetrix microarray data and quantitative RT-PCR. Following MYCNOS-01 or MYCN siRNA knockdown and MYCNOS-01 overexpression, transcript levels were assayed by quantitative RT-PCR and MYCN protein expression assessed by Western blot and immunofluorescence. Additionally, effects on cell growth, apoptosis and cell cycle profiles were determined by a metabolic assay, caspase activity and flow cytometry, respectively. RESULTS: MYCNOS-01 transcript levels were generally higher in NB and RMS tumor samples and cell lines with MYCN genomic amplification. RNA interference of MYCNOS-01 expression did not alter MYCN transcript levels but decreased MYCN protein levels. Conversely, MYCN reduction increased MYCNOS-01 transcript levels, creating a negative feedback loop on MYCN protein levels. Reduction of MYCNOS-01 or MYCN expression decreased cell growth in MYCN-amplified alveolar rhabdomyosarcoma and neuroblastoma cell lines. This is consistent with MYCNOS-01-mediated regulation of MYCN contributing to the phenotype observed. CONCLUSIONS: An alternative transcript of MYCNOS, MYCNOS-01, post-transcriptionally regulates MYCN levels and affects growth in MYCN-amplified rhabdomyosarcoma and neuroblastoma cells.


Assuntos
Regulação Neoplásica da Expressão Gênica , Proteína Proto-Oncogênica N-Myc/genética , Neuroblastoma/metabolismo , RNA Longo não Codificante/metabolismo , Rabdomiossarcoma Alveolar/metabolismo , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Humanos , Proteína Proto-Oncogênica N-Myc/metabolismo , Neuroblastoma/genética , Neuroblastoma/fisiopatologia , Rabdomiossarcoma Alveolar/genética , Rabdomiossarcoma Alveolar/fisiopatologia
4.
PLoS One ; 12(5): e0177749, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28542375

RESUMO

PURPOSE: To differentiate the plasma metabolomic profile of patients with age related macular degeneration (AMD) from that of controls, by Nuclear Magnetic Resonance (NMR) spectroscopy. METHODS: Two cohorts (total of 396 subjects) representative of central Portugal and Boston, USA phenotypes were studied. For each cohort, subjects were grouped according to AMD stage (early, intermediate and late). Multivariate analysis of plasma NMR spectra was performed, followed by signal integration and univariate analysis. RESULTS: Small changes were detected in the levels of some amino acids, organic acids, dimethyl sulfone and specific lipid moieties, thus providing some biochemical information on the disease. The possible confounding effects of gender, smoking history and age were assessed in each cohort and found to be minimal when compared to that of the disease. A similar observation was noted in relation to age-related comorbidities. Furthermore, partially distinct putative AMD metabolite fingerprints were noted for the two cohorts studied, reflecting the importance of nutritional and other lifestyle habits in determining AMD metabolic response and potential biomarker fingerprints. Notably, some of the metabolite changes detected were noted as potentially differentiating controls from patients diagnosed with early AMD. CONCLUSION: For the first time, this study showed metabolite changes in the plasma of patients with AMD as compared to controls, using NMR. Geographical origins were seen to affect AMD patients´ metabolic profile and some metabolites were found to be valuable in potentially differentiating controls from early stage AMD patients. Metabolomics has the potential of identifying biomarkers for AMD, and further work in this area is warranted.


Assuntos
Degeneração Macular/sangue , Degeneração Macular/metabolismo , Metabolômica , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Estudos Transversais , Feminino , Humanos , Espectroscopia de Ressonância Magnética , Masculino , Pessoa de Meia-Idade
5.
Int J Cancer ; 139(2): 467-79, 2016 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-26933761

RESUMO

The tetrahydroisoquinoline trabectedin is a marine compound with approved activity against human soft-tissue sarcoma. It exerts antiproliferative activity mainly by specific binding to the DNA and inducing DNA double-strand breaks (DSB). As homologous recombination repair (HRR)-deficient tumors are more susceptible to trabectedin, hyperthermia-mediated on-demand induction of HRR deficiency represents a novel and promising strategy to boost trabectedin treatment. For the first time, we demonstrate enhancement of trabectedin effectiveness in human sarcoma cell lines by heat and characterize cellular events and molecular mechanisms related to heat-induced effects. Hyperthermic temperatures (41.8 or 43°C) enhanced significantly trabectedin-related clonogenic cell death and G2/M cell cycle arrest followed by cell type-dependent induction of apoptosis or senescence. Heat combination increased accumulation of γH2AX foci as key marker of DSBs. Expression of BRCA2 protein, an integral protein of the HRR machinery, was significantly decreased by heat. Consequently, recruitment of downstream RAD51 to γH2AX-positive repair foci was almost abolished indicating relevant impairment of HRR by heat. Accordingly, enhancement of trabectedin effectiveness was significantly augmented in BRCA2-proficient cells by hyperthermia and alleviated in BRCA2 knockout or siRNA-transfected BRCA2 knockdown cells. In peripheral blood mononuclear cells isolated from sarcoma patients, increased numbers of nuclear γH2AX foci were detected after systemic treatment with trabectedin and hyperthermia of the tumor region. The findings establish BRCA2 degradation by heat as a key factor for a novel treatment strategy that allows targeted chemosensitization to trabectedin and other DNA damaging antitumor drugs by on-demand induction of HRR deficiency.


Assuntos
Antineoplásicos Alquilantes/farmacologia , Proteína BRCA2/metabolismo , Dioxóis/farmacologia , Hipertermia Induzida , Reparo de DNA por Recombinação/efeitos dos fármacos , Reparo de DNA por Recombinação/efeitos da radiação , Tetra-Hidroisoquinolinas/farmacologia , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Caspases/metabolismo , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos da radiação , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Resistencia a Medicamentos Antineoplásicos/efeitos da radiação , Histonas/metabolismo , Humanos , Modelos Biológicos , Ligação Proteica , Transporte Proteico , Proteólise/efeitos dos fármacos , Proteólise/efeitos da radiação , Rad51 Recombinase/metabolismo , Sarcoma/metabolismo , Sarcoma/patologia , Sarcoma/terapia , Trabectedina
7.
Sarcoma ; 2011: 402508, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21647361

RESUMO

Ewing's sarcoma family of tumours comprises a group of very aggressive diseases that are potentially curable with multimodality treatment. Despite the undoubted success of current treatment, approximately 30% of patients will relapse and ultimately die of disease. The insulin-like growth factor 1 receptor (IGF-1R) has been implicated in the genesis, growth, proliferation, and the development of metastatic disease in Ewing's sarcoma. In addition, IGF1-R has been validated, both in vitro and in vivo, as a potential therapeutic target in Ewing's sarcoma. Phase I studies of IGF-1R monoclonal antibodies reported several radiological and clinical responses in Ewing's sarcoma patients, and initial reports of several Phase II studies suggest that about a fourth of the patients would benefit from IGF-1R monoclonal antibodies as single therapy, with approximately 10% of patients achieving objective responses. Furthermore, these therapies are well tolerated, and thus far severe toxicity has been rare. Other studies assessing IGF-1R monoclonal antibodies in combination with traditional cytotoxics or other targeted therapies are expected. Despite, the initial promising results, not all patients benefit from IGF-1R inhibition, and consequently, there is an urgent need for the identification of predictive markers of response.

8.
PLoS One ; 6(5): e19846, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21611203

RESUMO

Receptor endocytosis is critical for cell signaling. IGF1R mediates an autocrine loop that is de-regulated in Ewing Sarcoma (ES) cells. Here we study the impact of IGF1R internalization, mediated by clathrin and caveolin-1 (CAV1), in ES signaling. We used clathrin and CAV1-siRNA to interfere in clathrin- and caveolin-dependent endocytosis. Chlorpromazine (CPMZ) and methyl-beta-cyclo-dextrin (MCD) were also used in order to inhibit clathrin- and caveolin-dependent endocytosis, respectively. We analyzed IGF1R internalization and co-localization with clathrin and CAV1 upon ligand binding, as well as the status of the IGF1R pathway, cellular proliferation, and the apoptosis of interfered and inhibited ES cells. We performed a high-throughput tyrosine kinase phosphorylation assay to analyze the effects of combining the IGF1R tyrosine kinase inhibitor AEW541 (AEW) with CPMZ or MCD on the intracellular phospho-proteome. We observed that IGF1R is internalized upon ligand binding in ES cells and that this process is dependent on clathrin or CAV1. The blockage of receptor internalization inhibited AKT and MAPK phosphorylation, reducing the proliferative rate of ES cells and increasing the levels of apoptosis. Combination of AEW with CPMZ or MCD largely enhanced these effects. CAV1 and clathrin endocytosis controls IGF1R internalization and signaling and has a profound impact on ES IGF1R-promoted survival signaling. We propose the combination of tyrosine-kinase inhibitors with endocytosis inhibitors as a new therapeutic approach to achieve a stronger degree of receptor inhibition in this, or other neoplasms dependent on IGF1R signaling.


Assuntos
Caveolina 1/metabolismo , Clatrina/metabolismo , Endocitose , Receptor IGF Tipo 1/metabolismo , Sarcoma de Ewing/metabolismo , Transdução de Sinais , Apoptose/efeitos dos fármacos , Caveolina 1/antagonistas & inibidores , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Clatrina/antagonistas & inibidores , Endocitose/efeitos dos fármacos , Humanos , Microscopia Confocal , Modelos Biológicos , Fosforilação/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Proteoma/metabolismo , Receptor IGF Tipo 1/antagonistas & inibidores , Sarcoma de Ewing/patologia
9.
Sarcoma ; 2011: 209736, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21437217

RESUMO

Rhabdomyosarcomas (RMS) are a heterogeneous group of tumors that share features of skeletal myogenesis and represent the most common pediatric soft tissue sarcoma. Even though significant advances have been achieved in RMS treatment, prognosis remains very poor for many patients. Several elements of the Insulin-like Growth Factor (IGF) pathway are involved in sarcomas, including RMS. The IGF2 ligand is highly expressed in most, if not all, RMS, and frequent overexpression of the receptor IGF1R is also found. This is confirmed here through mining expression profiling data of a large series of RMS samples. IGF signaling is implicated in the genesis, growth, proliferation, and metastasis of RMS. Blockade of this pathway is therefore a potential therapeutic strategy for the treatment of RMS. In this paper we examine the biological rationale for targeting the IGF pathway in RMS as well as the current associated preclinical and clinical experience.

10.
Cancer ; 116(15): 3692-701, 2010 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-20564079

RESUMO

BACKGROUND: In KIT-expressing Ewing sarcoma cell lines, the addition of doxorubicin to imatinib increases apoptosis, compared with imatinib or doxorubicin alone. On the basis of these in vitro data, the authors conducted a phase 1-2 trial of doxorubicin with imatinib in patients with gastrointestinal sarcoma tumors refractory to high-dose imatinib therapy. METHODS: Patients with metastatic gastrointestinal sarcoma tumor resistant to imatinib at 400 mg by mouth (p.o.) twice a day were eligible for this multicenter study, and received imatinib (400 mg p.o. every day [q.d.]) concomitantly with doxorubicin 15-20 mg/m2/weekly for 4 cycles (monthly cycles), followed by imatinib (400 mg p.o. q.d.) maintenance in nonprogressive patients. Spiral computed tomography and positron emission tomography with F18-fluorodeoxyglucose were done basally and after 2 months of therapy to evaluate response. An in vitro study assessed the effect of combining imatinib and doxorubicin. RESULTS: Twenty-six patients with progressive gastrointestinal sarcoma tumor were entered in the study. Treatment was well tolerated. Three (14%) of 22 evaluable patients had partial responses per Response Evaluation Criteria in Solid Tumors, and 8 (36%) had clinical benefit (partial response or stable disease for >or=6 months). Median progression-free survival (PFS) was 100 days (95% confidence interval [CI], 62-138), and median survival was 390 days (95% CI, 264-516). Interestingly, PFS was 211 days (95% CI, 52-370) in patients with wild type (WT) KIT and 82 days (95% CI, 53-111) in non-WT patients (10 mutant, 6 not assessed). A synergistic effect on cell line proliferation and apoptosis was found with imatinib and doxorubicin combination. CONCLUSIONS: Low-dose chemobiotherapy combination showed promising activity in heavily pretreated gastrointestinal sarcoma tumor patients, especially in those with WT-KIT genotype.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Doxorrubicina/administração & dosagem , Tumores do Estroma Gastrointestinal/tratamento farmacológico , Piperazinas/administração & dosagem , Pirimidinas/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Benzamidas , Intervalo Livre de Doença , Esquema de Medicação , Resistencia a Medicamentos Antineoplásicos , Feminino , Tumores do Estroma Gastrointestinal/diagnóstico por imagem , Tumores do Estroma Gastrointestinal/genética , Humanos , Mesilato de Imatinib , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons , Proteínas Proto-Oncogênicas c-kit/genética
11.
Semin Diagn Pathol ; 25(4): 304-16, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19013896

RESUMO

Bone and soft tissue sarcomas are an infrequent and heterogeneous group of mesenchymal tumors, including more than a hundred different entities attending to histological patterns. Sarcomas are quite resistant to conventional chemotherapy (anthracycline and ifosfamide) with the exception of some subtypes, such as Ewing's sarcoma (ES). New drugs with proved efficacy against sarcomas include taxanes, gemcitabine, and ET-743. Preclinical studies have also identified key molecular events leading to the progression and development of sarcomas which are good candidates to targeted therapy. Inhibitors of the tyrosine kinase receptors, such as IGF-1R, c-kit, PDGFR, VEGFR, or the mTOR signaling pathway, proteasome, angiogenesis, and stress response proteins are under clinical evaluation against sarcomas. ES, a tumor characterized by chromosomal translocations that originate gene fusions (EWS-FLI1, EWS-ERG), is an example of a good chemotherapy responder tumor whose survival rate shows a plateau in recent years. Preclinical studies have identified that new targets such as HSP90 are of relevance to ES. On the other hand, recent studies showed the role of cancer stem cells (CSCs) in sarcomas and the relevance of the identification of reliable molecular markers and possible therapeutic targets. New therapeutic approaches could be directed against CSCs. This review describes more recent targeted therapy in sarcomas, with special emphasis on ES and the role of CSCs. We also emphasize the role of high throughput proteomic techniques in identifying new therapeutic targets.


Assuntos
Antineoplásicos/farmacologia , Biomarcadores Tumorais , Sistemas de Liberação de Medicamentos/tendências , Sarcoma/tratamento farmacológico , Sarcoma/genética , Animais , Ensaios Clínicos como Assunto , Sistemas de Liberação de Medicamentos/métodos , Humanos , Células-Tronco Neoplásicas/fisiologia
12.
Cancer Res ; 68(15): 6260-70, 2008 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-18676850

RESUMO

Ewing Sarcoma (ES) shows several deregulated autocrine loops mediating cell survival and proliferation. Therefore, their blockade is a promising therapeutic approach. We previously reported the in vitro effect of insulin-like growth factor 1 receptor (IGF1R)/KIT pathway blockade on ES cell lines, and we now extend our observations to changes induced by this treatment in interacting proteins/networks. A proteomic analysis revealed that Heat Shock Protein (HSP)90 was differentially expressed between ES cell lines sensitive and resistant to specific IGF1R/KIT inhibitors. We therefore inhibited HSP90 with 17-allylamino-17-demethoxygeldanamycin (17-AAG) and siRNA, and observed that ES cell line growth and survival were reduced, especially in the resistant cell lines. Conversely, HSP90 induced-expression conferred resistance to anti-IGF1R/KIT treatment in the sensitive cell lines. 17-AAG treatment induced HSP90 client protein degradation, including AKT, KIT, or IGF1R, by inhibiting their physical interaction with HSP90. Xenograft models developed with A673 ES cell line confirmed that HSP90 inhibition, alone or combined with IGF1R inhibition, significantly reduced tumor growth and expression of client proteins. Remarkably, using two independent clinical sample sets, we have found that nearly half of IGF1R-positive tumors also show HSP90 overexpression. This delineates a subset of patients that could benefit from combination of anti-HSP90 agents when considering IGF1R-targeting therapies. Importantly, sensitivity to drugs such as ADW/IMA depends not only on the levels of expression and basal activation of IGF1R/KIT, but also, and for the first time reported in ES, on the development of the stress response mechanism. Accordingly, HSP90 expression could be a predictive factor of response to IGF1R-targeting therapies.


Assuntos
Antineoplásicos/uso terapêutico , Resistencia a Medicamentos Antineoplásicos , Proteínas de Choque Térmico HSP90/fisiologia , Receptor IGF Tipo 1/antagonistas & inibidores , Sarcoma de Ewing/tratamento farmacológico , Apoptose , Benzamidas , Western Blotting , Proliferação de Células , Eletroforese em Gel Bidimensional , Humanos , Mesilato de Imatinib , Técnicas In Vitro , Piperazinas/uso terapêutico , Pirimidinas/uso terapêutico , Pirróis/uso terapêutico , Sarcoma de Ewing/patologia
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