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1.
Ann Surg ; 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38771951

RESUMO

OBJECTIVE: We aimed to assess the levels of MDM2-DNA within extracellular vesicles (EVs) isolated from the serum of retroperitoneal liposarcoma (RLS) patients versus healthy donors, as well as within the same patients at the time of surgery versus post-operative surveillance visits. To determine whether EV-MDM2 may serve as a possible first-ever biomarker of liposarcoma recurrence. BACKGROUND: A hallmark of well-differentiated and de-differentiated (WD/DD) retroperitoneal liposarcoma is elevated MDM2 due to genome amplification, with recurrence rates of >50% even after complete resection. Imaging technologies frequently cannot resolve recurrent WD/DD-RLS versus postoperative scarring. Early detection of recurrent lesions, for which biomarkers are lacking, would guide surveillance and treatment decisions. METHODS: WD/DD-RLS serum samples were collected both at the time of surgery and during follow-up visits from 42 patients, along with sera from healthy donors (n=14). EVs were isolated, DNA purified and MDM2-DNA levels determined through q-PCR analysis. Non-parametric tests were employed to compare EV-MDM2 DNA levels from patients versus control group, as well as the time of surgery versus post-surgery conditions. RESULTS: EV-MDM2 levels were significantly higher in WD/DD-RLS than controls (P= 0.00085). Moreover, EV-MDM2 levels were remarkably decreased in WD/DD-RLS patients after resection (P=0.00036), reaching values comparable to control group (P=0.124). During post-operative surveillance, significant increases of EV-MDM2 was observed in some patients, correlating with CT scan evidence of recurrent or persistent post-resection disease. CONCLUSIONS: Serum EV-MDM2 may serve as a potential biomarker of early recurrent or post-operatively persistent WD/DD-RLS, a disease currently lacking such determinants.

2.
Front Cell Dev Biol ; 12: 1362696, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38500686

RESUMO

Background: Dedifferentiated liposarcoma is a formidable sarcoma subtype due to its high local recurrence rate and resistance to medical treatment. While 2D cell cultures are still commonly used, 3D cell culture systems have emerged as a promising alternative, particularly scaffold-based techniques that enable the creation of 3D models with more accurate cell-stroma interactions. Objective: To investigate how 3D structures with or without the scaffold existence would affect liposarcoma cell lines growth morphologically and biologically. Methods: Lipo246 and Lipo863 cell lines were cultured in 3D using four different methods; Matrigel® ECM scaffold method, Collagen ECM scaffold method, ULA plate method and Hanging drop method, in addition to conventional 2D cell culture methods. All samples were processed for histopathological analysis (HE, IHC and DNAscope™), Western blot, and qPCR; moreover, 3D collagen-based models were treated with different doses of SAR405838, a well-known inhibitor of MDM2, and cell viability was assessed in comparison to 2D model drug response. Results: Regarding morphology, cell lines behaved differently comparing the scaffold-based and scaffold-free methods. Lipo863 formed spheroids in Matrigel® but not in collagen, while Lipo246 did not form spheroids in either collagen or Matrigel®. On the other hand, both cell lines formed spheroids using scaffold-free methods. All samples retained liposarcoma characteristic, such as high level of MDM2 protein expression and MDM2 DNA amplification after being cultivated in 3D. 3D collagen samples showed higher cell viability after SAR40538 treatment than 2D models, while cells sensitive to the drug died by apoptosis or necrosis. Conclusion: Our results prompt us to extend our investigation by applying our 3D models to further oncological relevant applications, which may help address unresolved questions about dedifferentiated liposarcoma biology.

3.
Dental press j. orthod. (Impr.) ; 29(1): e24spe1, 2024. graf
Artigo em Inglês | LILACS-Express | LILACS, BBO - Odontologia | ID: biblio-1534311

RESUMO

ABSTRACT Introduction: The use of clear aligners as an alternative to fixed orthodontic appliances has become popular due to the aesthetic demands of adult patients seeking orthodontic treatment. However, orthodontists' lack of knowledge about the legal consequences of their activities, and the lack of solid scientific evidence raise concerns regarding civil liability in this type of treatment. Marketing campaigns of manufacturing companies often exaggerate promises of results, and ignore the lack of scientific evidence. Patients, as consumers, are protected by the Consumer Protection Code, whereas orthodontists are considered treatment providers. Therefore, they can be held liable for damage caused to patients, whether by subjective or objective fault. Objective: This article aims to identify the civil responsibilities of orthodontists and aligner manufacturing companies, by means of a literature review, providing basic legal guidance to help professionals protect themselves from possible lawsuits related to treatment with orthodontic aligners. Conclusions: The study highlights the importance of knowledge of legal notions in treatments with orthodontic aligners by orthodontists, who should legally safeguard themselves through individual written contracts, avoiding obligation of results. In addition, in cases of legal claims, it is possible that the manufacturing companies are jointly and severally liable for possible damages claimed by the patient.


RESUMO Introdução: O uso de alinhadores transparentes como alternativa aos aparelhos ortodônticos fixos tem se tornado popular, devido às demandas estéticas dos pacientes adultos em busca de tratamento ortodôntico. No entanto, a falta de conhecimento dos ortodontistas sobre as consequências jurídicas de suas atividades, e a falta de evidências científicas sólidas levantam preocupações em relação à responsabilidade civil nesse tipo de tratamento. Muitas vezes, as campanhas de marketing das empresas fabricantes exageram nas promessas de resultados e desconsideram a falta de evidências científicas. O paciente, como consumidor, é protegido pelo Código de Defesa do Consumidor, e o ortodontista é considerado um fornecedor de tratamento. Portanto, ele pode ser responsabilizado por danos causados ao paciente, seja por culpa subjetiva ou objetiva. Objetivo: Identificar, por meio de uma revisão bibliográfica, as responsabilidades civis dos ortodontistas e das empresas fabricantes de alinhadores, fornecendo orientações jurídicas básicas para ajudar os profissionais a se protegerem de possíveis demandas judiciais relacionadas ao tratamento com alinhadores ortodônticos. Conclusões: O estudo destaca a importância do conhecimento de noções jurídicas em tratamentos com alinhadores ortodônticos, devendo o profissional resguardar-se juridicamente por meio de contratos individuais por escrito, prevenindo-se de assumir uma obrigação de resultado com o paciente. Além disso, em casos de demandas judiciais, é possível que as empresas fabricantes respondam solidariamente a possíveis danos reclamados pelo paciente.

4.
Hum Cell ; 36(3): 1081-1089, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36763259

RESUMO

Sarcomas are rare malignancies, the number of reports is limited, and this rarity makes further research difficult even though liposarcoma is one of major sarcomas. 2D cell culture remains an important role in establishing basic tumor biology research, but its various shortcomings and limitations are still of concern, and it is now well-accepted that the behavior of 3D-cultured cells is more reflective of in vivo cellular responses compared to 2D models. This study aimed to establish 3D cell culture of liposarcomas using two different methods: scaffold-based (Matrigel extracellular matrix [ECM] scaffold method) and scaffold-free (Ultra-low attachment [ULA] plate). Lipo246, Lipo224 and Lipo863 cell lines were cultured, and distinctive differences in structures were observed in Matrigel 3D model: Lipo224 and Lipo863 formed spheroids, whereas Lipo246 grew radially without forming spheres. In ULA plate approaches, all cell lines formed spheroids, but Lipo224 and Lipo863 spheroids showed bigger size and looser aggregation than Lipo246. Formalin fixed, paraffin embedded (FFPE) blocks were obtained from all 3D models, confirming the spheroid structures. The expression of MDM2, Ki-67 positivity and MDM2 amplification were confirmed by IHC and DNAscope™, respectively. Protein and DNA were extracted from all samples and MDM2 upregulation was confirmed by western blot and qPCR analysis. After treatment with MDM2 inhibitor SAR405838, DDLPS spheroids demonstrated different sensitivity patterns from 2D models. Taken together, we believed that 3D models would have a possibility to provide us a new predictability of efficacy and toxicity, and considered as one important process in in vitro pre-clinical phase prior to moving forward to clinical trials.


Assuntos
Lipossarcoma , Sarcoma , Neoplasias de Tecidos Moles , Humanos , Lipossarcoma/genética , Lipossarcoma/terapia , Sarcoma/patologia , Linhagem Celular , Esferoides Celulares/patologia
5.
Rev. Assoc. Med. Bras. (1992, Impr.) ; 69(2): 308-313, Feb. 2023. tab
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1422617

RESUMO

SUMMARY OBJECTIVE: This study aimed to evaluate the influence of chronic pain on functionality and its consequences on work and patient income. METHODS: A total of 103 patients from the Multidisciplinary Pain Center of the Clinics Hospital of Universidade Federal de Minas Gerais were interviewed between January 2020 and June 2021, applying questionnaires on mobile devices. Socioeconomic data, multidimensional characterization of pain, and instruments for assessing pain functionality and intensity were analyzed. Pain intensity was categorized as mild, moderate, or intense for comparative analysis. Ordinal logistic regression was used to identify risk factors and variables that jointly influence the outcome of pain intensity. RESULTS: The patients had a median age of 55 years, were predominantly female, married or in a stable relationship, white race, and completed high school. The median family income was R$2,200. Most patients were retired due to disability and pain-related causes. Functionality analysis showed severe disability directly associated with pain intensity. The financial impacts observed were correlated with the pain intensity of the patients. Age was a risk factor for pain intensity, while sex, family income, and duration of pain served as protective factors. CONCLUSION: Chronic pain was associated with severe disability, decreased productivity, and exit from the labor market, with a negative impact on financial condition. Age, sex, family income, and duration of pain were directly associated with pain intensity.

6.
Braz. j. oral sci ; 21: e226415, jan.-dez. 2022. tab
Artigo em Inglês | LILACS, BBO - Odontologia | ID: biblio-1354995

RESUMO

Aim: Facial orthopaedic treatments based on the stimulation or restrictions of craniofacial bone growth are more effective when carried out during the pubertal growth spurt. The aim of this cross-sectional study was to evaluate the reproducibility of two cervical vertebrae methods (CVM) with manual tracing and direct visual inspection. Methods: A sample of 60 lateral cephalometric radiographs (10 of each of the 6 CVM stages) was randomly selected from 171 records. 5 orthodontists classified these radiographs according to the skeletal maturation stage in 2002 and 2005, and the application of both methods was conducted by direct visual inspection and evaluation through manual tracing. Results: The average reliability of the two methods determination and the two forms of evaluation was substantial. The direct visual inspection evaluation showed the highest reliability and agreement interexaminer values for both methods, as well as the intraexaminers evaluation. Conclusion: The reproducibility of CVM method was substantial, indicating its clinical use to determine the skeletal maturity and the ideal moment for treatment execution


Assuntos
Desenvolvimento Ósseo , Vértebras Cervicais , Reprodutibilidade dos Testes
7.
PLoS One ; 17(10): e0276047, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36240209

RESUMO

Mutation in the CTNNB1 gene, leading to a deregulation of the WTN/ß-catenin pathway, is a common feature of desmoid tumors (DTs). Many ß-catenin inhibitors have recently been tested in clinical studies; however, BC2059 (also referred as Tegavivint), a selective inhibitor of nuclear ß-catenin that works through binding TBL-1, is the only one being evaluated in a clinical study, specifically for treatment of desmoid tumor patients. Preclinical studies on BC2059 have shown activity in multiple myeloma, acute myeloid leukemia and osteosarcoma. Our preclinical studies provide data on the efficacy of BC2059 in desmoid cell lines, which could help provide insight regarding antitumor activity of this therapy in desmoid tumor patients. In vitro activity of BC2059 was evaluated using desmoid tumor cell lines. Ex vivo activity of BC2059 was assessed using an explant tissue culture model. Pharmacological inhibition of the nuclear ß-catenin activity using BC2059 markedly inhibited cell viability, migration and invasion of mutated DT cells, but with lower effect on wild-type DTs. The decrease in cell viability of mutated DT cells caused by BC2059 was due to apoptosis. Treatment with BC2059 led to a reduction of ß-catenin-associated TBL1 in all mutated DT cells, resulting in a reduction of nuclear ß-catenin. mRNA and protein levels of AXIN2, a ß-catenin target gene, were also found to be downregulated after BC2059 treatment. Taken together, our results demonstrate that nuclear ß-catenin inhibition using BC2059 may be a novel therapeutic strategy for desmoid tumor treatment, especially in patients with CTNNB1 mutation.


Assuntos
Neoplasias Ósseas , Fibromatose Agressiva , Fibromatose Agressiva/patologia , Humanos , Mutação , RNA Mensageiro/genética , Via de Sinalização Wnt , beta Catenina/metabolismo
8.
J Invertebr Pathol ; 194: 107827, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36108793

RESUMO

Aedes aegypti transmits arbovirus, which is a public health concern. Certain filamentous fungi have the potential to control the disease. Here, the effects of Metarhizium anisopliae s.l. CG 153, Beauveria bassiana s.l. CG 206 and Schinus molle L. were investigated against Aedes aegypti larvae. In addition, the effect of essential oil on fungal development was analyzed. Fungal germination was assessed after combination with essential oil at 0.0025 %, 0.0075 %, 0.005 %, or 0.01 %; all of the oil concentrations affected germination except 0.0025 % (v/v). Larvae were exposed to 0.0025 %, 0.0075 %, 0.005 %, or 0.01 % of the essential oil or Tween 80 at 0.01 %; however, only the essential oil at 0.0025 % achieved similar results as the control. Larvae were exposed to fungi at 107 conidia mL-1 alone or in combination with the essential oil at 0.0025 %. Regardless of the combination, M. anisopliae reduced the median survival time of mosquitoes more than B. bassiana. The cumulative survival of mosquitoes exposed to M. anisopliae alone or in combination with essential oil was 7.5 % and 2 %, respectively, and for B. bassiana, it was 75 % and 71 %, respectively. M. anisopliae + essential oil had a synergistic effect against larvae, whereas B. bassiana + essential oil was antagonistic. Scanning and transmission electron microscopy, and histopathology confirmed that the interaction of M. anisopliae was through the gut and hemocoel. In contrast, the mosquito's gut was the main route for invasion by B. bassiana. Results from gas chromatography studies demonstrated sabinene and bicyclogermacrene as the main compounds of S. molle, and the in-silico investigation found evidence that both compounds affect a wide range of biological activity. For the first time, we demonstrated the potential of S. molle and its interaction with both fungal strains against A. aegypti larvae. Moreover, for the first time, we reported that S. molle might be responsible for significant changes in larval physiology. This study provides new insights into host-pathogen interplay and contributes to a better understanding of pathogenesis in mosquitoes, which have significant consequences for biological control strategies.


Assuntos
Aedes , Anacardiaceae , Beauveria , Metarhizium , Óleos Voláteis , Aedes/microbiologia , Animais , Beauveria/fisiologia , Larva/microbiologia , Metarhizium/fisiologia , Óleos Voláteis/farmacologia , Controle Biológico de Vetores/métodos , Polissorbatos/farmacologia
9.
J Extracell Vesicles ; 11(9): e12251, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36043432

RESUMO

EVs have emerged as an important component in tumour initiation, progression and metastasis. Although notable progresses have been made, the detection of EV cargoes remain significantly challenging for researchers to practically use; faster and more convenient methods are required to validate the EV cargoes, especially as biomarkers. Here we show, the possibility of examining embedded EVs as substrates to be used for detecting DNA amplification through ultrasensitive in situ hybridization (ISH). This methodology allows the visualization of DNA targets in a more direct manner, without time consuming optimization steps or particular expertise. Additionally, formalin-fixed paraffin-embedded (FFPE) blocks of EVs allows long-term preservation of samples, permitting future studies. We report here: (i) the successful isolation of EVs from liposarcoma tissues; (ii) the EV embedding in FFPE blocks (iii) the successful selective, specific ultrasensitive ISH examination of EVs derived from tissues, cell line, and sera; (iv) and the detection of MDM2 DNA amplification in EVs from liposarcoma tissues, cell lines and sera. Ultrasensitive ISH on EVs would enable cargo study while the application of ISH to serum EVs, could represent a possible novel methodology for diagnostic confirmation. Modification of probes may enable researchers to detect targets and specific DNA alterations directly in tumour EVs, thereby facilitating detection, diagnosis, and improved understanding of tumour biology relevant to many cancer types.


Assuntos
Vesículas Extracelulares , Lipossarcoma , DNA/metabolismo , Vesículas Extracelulares/metabolismo , Humanos , Hibridização In Situ , Lipossarcoma/diagnóstico
10.
Rev. med. (Säo Paulo) ; 101(4): e-175074, jul.-ago. 2022.
Artigo em Inglês, Português | LILACS-Express | LILACS | ID: biblio-1392163

RESUMO

Linfomas cutâneos primários são a segunda forma mais comum de linfomas extranodais, sendo os linfomas de células B, (CBCLs) representantes de 20 a 30% dos casos. O linfoma cutâneo difuso de grandes células B, Tipo Perna (PCDLBCL-LT), representa o tipo mais agressivo de CBCLs. Na maioria dos casos, a apresentação clínica é caracterizada por placas ou tumores solitários, ora ulcerados, em uma ou ambas as pernas, de rápido crescimento. O diagnóstico é confirmado através do estudo histopatológico e imunohistoquímico. O tratamento é realizado por meio de quimioterapia e seu prognóstico é reservado com uma sobrevida de 50% a 60% em 05 anos. O objetivo deste trabalho é relatar um caso atendido de linfoma cutâneo primário difuso de grandes células B, tipo perna em um paciente de 75 anos, do sexo masculino com apresentação clínica clássica e desfecho desfavorável, realizar uma revisão bibliográfica do período de 2010 a 2020 na base de dados PUBMED sobre o assunto, dada sua raridade e agressividade ímpar. As informações foram obtidas através de revisão do prontuário, registro fotográfico e revisão da literatura. Por tudo isso, pode-se concluir a importância de estudos multidisciplinares, envolvendo dermatologistas, hematologistas, oncologistas e patologistas para que o diagnóstico e tratamento sejam instituídos o mais precoce possível, visto a raridade e agressividade do PCDLBCL-LT. [au]


Primary cutaneous lymphomas are the second most common form of extranodal lymphomas; with B cell lymphomas (CBCLs) representing 20 to 30% of cases. Diffuse cutaneous large B cell lymphoma, leg type (PCDLBCL-LT), represents the most aggressive type of CBCLs. In most cases, the clinical presentation is characterized by solitary plaques or tumors, sometimes ulcerated, on one or both legs, of rapid growth. The diagnosis is confirmed through histopathological and immunohistochemistry studies. Treatment is carried out through chemotherapy and its prognosis is reserved with a 50% to 60% survival in 5 years. The objective of this work is to report a case of diffuse primary B-cell cutaneous lymphoma, leg type in a 75-year-old male patient with a classic clinical presentation and unfavorable outcome, to perform a literary review from 2010 to 2020 in the PUBMED database on the subject, given its rarity and unique aggressiveness. The data was obtained by reviewing the medical record, photographic record and literature review. For all this, it is possible to conclude the importance of multidisciplinary studies, involving dermatologists, hematologists, oncologists and pathologists so that the diagnosis and treatment are instituted as early as possible, given the rarity and aggressiveness of the PCDLBCL-LT. [au]

11.
Cancers (Basel) ; 14(6)2022 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-35326514

RESUMO

Liposarcoma (LPS) is the most prevalent soft tissue sarcoma histological subtype. When it occurs in the abdomen the overall survival rate is as low as 10% at 10 years and is fraught with high rates of recurrence, particularly for the more aggressive dedifferentiated subtype. Surgery remains the mainstay of treatment. Systemic therapies for the treatment of metastatic or unresectable disease have low response rates. Deep understanding of well-differentiated and de-differentiated LPS (WDLPS and DDLPS, respectively) oncologic drivers is necessary for the development of new efficacious targeted therapies for the management of this disease. This review discusses the current treatments under evaluation for retroperitoneal DDLPS and the potential targetable pathways in DDLPS.

12.
J Surg Oncol ; 125(2): 239-245, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34586640

RESUMO

Soft tissue sarcomas (STS) are a heterogeneous group of tumors that arise from mesenchymal tissue. Investigation at the molecular level has been challenging due to the rarity of STS and the number of histologic subtypes. However, recent research has provided new insight into potential genomic, proteomic, and immunological biomarkers of STS. The identification of biomarkers can improve diagnosis, prognosis, and prediction of recurrence and treatment response. This review provides an understanding of biomarkers, discussing the current status of biomarker research in STS.


Assuntos
Biomarcadores Tumorais , Sarcoma/diagnóstico , Antígeno B7-H1/análise , Ácidos Nucleicos Livres/análise , DNA Tumoral Circulante/análise , Vesículas Extracelulares/fisiologia , Humanos , MicroRNAs/análise , Proteínas Proto-Oncogênicas c-mdm2/análise , Proteínas Proto-Oncogênicas c-mdm2/genética , Sarcoma/genética
13.
Braz. J. Pharm. Sci. (Online) ; 58: e20400, 2022. tab
Artigo em Inglês | LILACS | ID: biblio-1403737

RESUMO

Abstract Cardiovascular diseases (CVD) are one of the main causes of mortality in the world. Dyslipidemia treatment can reduce the number of deaths caused by CVD, by decreasing the lipid profile. Evaluate the pharmacotherapeutic follow-up effectiveness in patients with dyslipidemia, regarding clinical and laboratory aspects. A quasi-experimental trial was performed in 12 months. The studied population was included patients with dyslipidemia who received a pharmacotherapeutic follow-up, which was evaluated according to the Pharmacotherapy Workup developed by the Brazilian Ministry of Health. Clinical and laboratory evaluations were performed at the baseline, after a 6 and 12-months period. The statistical analyzes were performed with the normality test of Lilliefors, Cramer Von Misses, and Anderson Darling, later the t-paired test. This study demonstrated that after 6-months of intervention, statistically significant results were verified in the reduction of LDL-cholesterol, total cholesterol, increase in HDL-cholesterol, and reduction in the blood pressure. It was observed that for high-risk patients, the achievement of targets in the lipid profile and HbA1C occurred only after 12-months, because, this population needs more aggressive targets and expressive interventions. Pharmacotherapeutic follow-up in patients with dyslipidemia reduced lipid blood levels and promoted positive clinical and laboratory outcomes.


Assuntos
Pacientes/classificação , Sistema Único de Saúde , Atenção à Saúde , Tratamento Farmacológico , Dislipidemias/diagnóstico , Necessidades e Demandas de Serviços de Saúde
14.
Toxins (Basel) ; 13(12)2021 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-34941695

RESUMO

Cathepsin L (CatL) is a lysosomal cysteine protease primarily involved in the terminal degradation of intracellular and endocytosed proteins. More specifically, in humans, CatL has been implicated in cancer progression and metastasis, as well as coronary artery diseases and others. Given this, the search for potent CatL inhibitors is of great importance. In the search for new molecules to perform proteolytic activity regulation, salivary secretions from hematophagous animals have been an important source, as they present protease inhibitors that evolved to disable host proteases. Based on the transcriptome of the Haementeria vizzotoi leech, the cDNA of Cystatin-Hv was selected for this study. Cystatin-Hv was expressed in Pichia pastoris and purified by two chromatographic steps. The kinetic results using human CatL indicated that Cystatin-Hv, in its recombinant form, is a potent inhibitor of this protease, with a Ki value of 7.9 nM. Consequently, the present study describes, for the first time, the attainment and the biochemical characterization of a recombinant cystatin from leeches as a potent CatL inhibitor. While searching out for new molecules of therapeutic interest, this leech cystatin opens up possibilities for the future use of this molecule in studies involving cellular and in vivo models.


Assuntos
Inibidores de Cisteína Proteinase/química , Sanguessugas/química , Saccharomycetales/metabolismo , Animais , Catepsina L , Cistatinas/química , Cistatinas/genética , Cistatinas/metabolismo , DNA Complementar , Humanos , Sanguessugas/genética , Proteínas Recombinantes
15.
Int J Oncol ; 58(6)2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33786613

RESUMO

Acute myeloid leukemia (AML) is a complex hematological disorder characterized by blockage of differentiation and high proliferation rates of myeloid progenitors. Anthracycline and cytarabine­based therapy has remained the standard treatment for AML over the last four decades. Although this treatment strategy has increased survival rates, patients often develop resistance to these drugs. Despite efforts to understand the mechanisms underlying cytarabine resistance, there have been few advances in the field. The present study developed an in vitro AML cell line model resistant to cytarabine (HL­60R), and identified chromosomal aberrations by karyotype evaluation and potential molecular mechanisms underlying chemoresistance. Cytarabine decreased cell viability, as determined by MTT assay, and induced cell death and cell cycle arrest in the parental HL­60 cell line, as revealed by Annexin V/propidium iodide (PI) staining and PI DNA incorporation, respectively, whereas no change was observed in the HL­60R cell line. In addition, the HL­60R cell line exhibited a higher tumorigenic capacity in vivo compared with the parental cell line. Notably, no reduction in tumor volume was detected in mice treated with cytarabine and inoculated with HL­60R cells. In addition, western blotting revealed that the protein expression levels of Bcl­2, X­linked inhibitor of apoptosis protein (XIAP) and c­Myc were upregulated in HL­60R cells compared with those in HL­60 cells, along with predominant nuclear localization of the p50 and p65 subunits of NF­κB in HL­60R cells. Furthermore, the antitumor effect of LQB­118 pterocarpanquinone was investigated; this compound induced apoptosis, a reduction in cell viability and a decrease in XIAP expression in cytarabine­resistant cells. Taken together, these data indicated that acquired cytarabine resistance in AML was a multifactorial process, involving chromosomal aberrations, and differential expression of apoptosis and cell proliferation signaling pathways. Furthermore, LQB­118 could be a potential alternative therapeutic approach to treat cytarabine­resistant leukemia cells.


Assuntos
Aberrações Cromossômicas , Leucemia Mieloide Aguda/tratamento farmacológico , Naftoquinonas/farmacologia , Pterocarpanos/farmacologia , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Citarabina/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HL-60 , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Masculino , Camundongos , Naftoquinonas/uso terapêutico , Pterocarpanos/uso terapêutico , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/genética , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Crit Rev Oncol Hematol ; 160: 103281, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33667660

RESUMO

Acute myeloid leukemia (AML) is one of the most common hematological neoplasia causing death worldwide. The long-term overall survival is unsatisfactory due to many factors including older age, genetic heterogeneity and molecular characteristics comprising additional mutations, and resistance to chemotherapeutic drugs. The expression of ABCB1/P-glycoprotein, ABCC1/MRP1, ABCG2/BCRP and LRP transporter proteins is considered the major reason for multidrug resistance (MDR) in AML, however conflicting data have been reported. Here, we review the main issues about drug transporter proteins in AML clinical scenario, and highlight the clinicopathological significance of MDR phenotype associated with ABCB1 polymorphisms and FLT3 mutation.


Assuntos
Leucemia Mieloide Aguda , Preparações Farmacêuticas , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP , Idoso , Resistencia a Medicamentos Antineoplásicos , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo
17.
Int J Mol Sci ; 22(2)2021 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-33477394

RESUMO

Protease inhibitors (PIs) are ubiquitous regulatory proteins present in all kingdoms. They play crucial tasks in controlling biological processes directed by proteases which, if not tightly regulated, can damage the host organism. PIs can be classified according to their targeted proteases or their mechanism of action. The functions of many PIs have now been characterized and are showing clinical relevance for the treatment of human diseases such as arthritis, hepatitis, cancer, AIDS, and cardiovascular diseases, amongst others. Other PIs have potential use in agriculture as insecticides, anti-fungal, and antibacterial agents. PIs from tick salivary glands are special due to their pharmacological properties and their high specificity, selectivity, and affinity to their target proteases at the tick-host interface. In this review, we discuss the structure and function of PIs in general and those PI superfamilies abundant in tick salivary glands to illustrate their possible practical applications. In doing so, we describe tick salivary PIs that are showing promise as drug candidates, highlighting the most promising ones tested in vivo and which are now progressing to preclinical and clinical trials.


Assuntos
Inibidores de Proteases/isolamento & purificação , Inibidores de Proteases/uso terapêutico , Saliva/metabolismo , Animais , Interações Hospedeiro-Parasita/genética , Interações Hospedeiro-Parasita/imunologia , Humanos , Saliva/química , Glândulas Salivares/metabolismo , Carrapatos/metabolismo , Transcriptoma/genética
18.
Rev. bioét. (Impr.) ; 28(4): 628-636, out.-dez. 2020.
Artigo em Português | LILACS | ID: biblio-1155742

RESUMO

Resumo Neste artigo pretende-se analisar problemas bioéticos relativos às populações em situação de rua a partir dos conceitos de homo sacer, de Giorgio Agamben, e de hospitalidade incondicional, de Jacques Derrida. Como elementos-chave destacam-se a invisibilidade dessas populações e o reconhecimento de que profissionais e instituições de saúde devem operar em lógica de cultura hospitaleira, que considere o cuidado às pessoas em situação de rua como significativa ação ética.


Abstract This article aims to analyze bioethical issues related to homeless persons based on the concepts of homo sacer, by Giorgio Agamben, and unconditional hospitality, by Jacques Derrida. We considered the following key elements: the invisibility of these people and the recognition that health professionals and institutions must operate within the logic of a hospitable culture, considering care for this population as a significant ethical action.


Resumen En este artículo, se pretende analizar los problemas bioéticos relativos a las personas sin hogar con base en los conceptos de homo sacer, de Giorgio Agamben, y hospitalidad incondicional, de Jacques Derrida. Como elementos clave se destacan la invisibilidad de dichas poblaciones y el reconocimiento de que los profesionales e instituciones de salud deben operar en una lógica de la cultura hospitalaria, que tenga en cuenta el cuidado a las personas sin hogar como significativa acción ética.


Assuntos
Humanos , Masculino , Feminino , Atenção Primária à Saúde , Pessoas Mal Alojadas , Ética
19.
Einstein (Sao Paulo) ; 18: eRC5409, 2020.
Artigo em Inglês, Português | MEDLINE | ID: mdl-33174970

RESUMO

Percutaneous endoscopic gastrostomy is used to provide enteral nutritional support for patients with obstructive oropharyngeal or esophageal neoplasms. The placement of the catheter is considered safe, with few complications. Despite this, a specific complication that is considered rare, has been increasingly described in the literature, i.e., metastasis of head and neck cancer in the gastrostomy stoma. In this report, we described a case of metastasis of squamous cell carcinoma of the larynx in the gastrostomy site, and discussed the possible etiologies and alternatives, seeking to reduce the incidence of this complication.


Assuntos
Carcinoma de Células Escamosas/secundário , Neoplasias Esofágicas/patologia , Gastrostomia/efeitos adversos , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias Laríngeas/patologia , Neoplasias Orofaríngeas/patologia , Neoplasias Gástricas/secundário , Carcinoma de Células Escamosas/diagnóstico por imagem , Carcinoma de Células Escamosas/terapia , Nutrição Enteral/efeitos adversos , Neoplasias de Cabeça e Pescoço/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Neoplasias Gástricas/cirurgia
20.
Oncogene ; 39(34): 5589-5600, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32651460

RESUMO

Wnt/ß-catenin signaling is one of the key cascades regulating embryogenesis and tissue homeostasis; it has also been intimately associated with carcinogenesis. This pathway is deregulated in several tumors, including colorectal cancer, breast cancer, and desmoid tumors. It has been shown that CTNNB1 exon 3 mutations are associated with an aggressive phenotype in several of these tumor types and may be associated with therapeutic tolerance. Desmoid tumors typically have a stable genome with ß-catenin mutations as a main feature, making these tumors an ideal model to study the changes associated with different types of ß-catenin mutations. Here, we show that the apoptosis mechanism is deregulated in ß-catenin S45F mutants, resulting in decreased induction of apoptosis in these cells. Our findings also demonstrate that RUNX3 plays a pivotal role in the inhibition of apoptosis found in the ß-catenin S45F mutants. Restoration of RUNX3 overcomes this inhibition in the S45F mutants, highlighting it as a potential therapeutic target for malignancies harboring this specific CTNNB1 mutation. While the regulatory effect of RUNX3 in ß-catenin is already known, our results suggest the possibility of a feedback loop involving these two genes, with the CTNNB1 S45F mutation downregulating expression of RUNX3, thus providing additional possible novel therapeutic targets for tumors having deregulated Wnt/ß-catenin signaling induced by this mutation.


Assuntos
Neoplasias Abdominais/genética , Polipose Adenomatosa do Colo/genética , Apoptose/genética , Subunidade alfa 3 de Fator de Ligação ao Core/genética , Fibromatose Agressiva/genética , Mutação de Sentido Incorreto , Via de Sinalização Wnt/genética , beta Catenina/genética , Neoplasias Abdominais/metabolismo , Neoplasias Abdominais/patologia , Polipose Adenomatosa do Colo/metabolismo , Polipose Adenomatosa do Colo/patologia , Linhagem Celular Tumoral , Subunidade alfa 3 de Fator de Ligação ao Core/metabolismo , Regulação para Baixo , Fibromatose Agressiva/metabolismo , Fibromatose Agressiva/patologia , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Humanos , beta Catenina/metabolismo
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