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1.
Int J Mol Sci ; 19(3)2018 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-29534015

RESUMO

Classical Hodgkin lymphoma (cHL) cells overexpress heat-shock protein 90 (HSP90), an important intracellular signaling hub regulating cell survival, which is emerging as a promising therapeutic target. Here, we report the antitumor effect of celastrol, an anti-inflammatory compound and a recognized HSP90 inhibitor, in Hodgkin and Reed-Sternberg cell lines. Two disparate responses were recorded. In KM-H2 cells, celastrol inhibited cell proliferation, induced G0/G1 arrest, and triggered apoptosis through the activation of caspase-3/7. Conversely, L428 cells exhibited resistance to the compound. A proteomic screening identified a total of 262 differentially expressed proteins in sensitive KM-H2 cells and revealed that celastrol's toxicity involved the suppression of the MAPK/ERK (extracellular signal regulated kinase/mitogen activated protein kinase) pathway. The apoptotic effects were preceded by a decrease in RAS (proto-oncogene protein Ras), p-ERK1/2 (phospho-extracellular signal-regulated Kinase-1/2), and c-Fos (proto-oncogene protein c-Fos) protein levels, as validated by immunoblot analysis. The L428 resistant cells exhibited a marked induction of HSP27 mRNA and protein after celastrol treatment. Our results provide the first evidence that celastrol has antitumor effects in cHL cells through the suppression of the MAPK/ERK pathway. Resistance to celastrol has rarely been described, and our results suggest that in cHL it may be mediated by the upregulation of HSP27. The antitumor properties of celastrol against cHL and whether the disparate responses observed in vitro have clinical correlates deserve further research.


Assuntos
Antineoplásicos/farmacologia , Resistencia a Medicamentos Antineoplásicos , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Doença de Hodgkin/metabolismo , Células de Reed-Sternberg/metabolismo , Triterpenos/farmacologia , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Humanos , Sistema de Sinalização das MAP Quinases , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Triterpenos Pentacíclicos , Proteoma , Proto-Oncogene Mas , Células de Reed-Sternberg/efeitos dos fármacos , Proteínas ras/metabolismo
2.
Oncology ; 89(3): 175-86, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25833149

RESUMO

AIM: To show additional prognostic information about the mutational profile and new International Association for the Study of Lung Cancer/American Thoracic Society/European Respiratory Society (IASLC/ATS/ERS) classification of adenocarcinoma (ADC) in patients without epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor treatments. METHODS: In human lung ADC patients (n = 125), including 24 lepidic, 67 acinar, 23 papillary, and 11 solid predominant subtypes, EGFR and KRAS were sequenced, and anaplastic lymphoma kinase (ALK) rearrangements were screened using fluorescence in situ hybridization (FISH). RESULTS: EGFR was mutated in 21.6% of patients with 19.57% showing a mean expression. The most frequent EGFR mutation was a deletion in exon 19, followed by an L858R amino acid substitution in exon 21. KRAS was mutated in 26.4% of patients with 50% displaying mean expression. ALK rearrangement was detected in 6 patients (4.8%). Predominant acinar ADC was strongly associated with EGFR and KRAS mutation. Clinical stage, lymph node metastases, and EGFR mutation in exon 18 showed a significant difference in disease-free and overall survival, but only a trend significance for EGFR and KRAS mutations. Multivariate analysis revealed that men aged >71 years, with a history of smoking (<72 packs/year), clinical stage I/II, and acinar histologic subtype presented better survival than women aged ≤ 71 years, with a history of smoking (>72 packs/year), and having a predominant solid ADC and EGFR mutation in exon 18. CONCLUSIONS: These results indicate that the mutational profile and new IASLC/ATS/ERS classification provide additional prognostic information about lung ADC.


Assuntos
Adenocarcinoma/classificação , Adenocarcinoma/genética , Receptores ErbB/genética , Rearranjo Gênico , Neoplasias Pulmonares/classificação , Neoplasias Pulmonares/genética , Mutação , Proteínas Proto-Oncogênicas/genética , Receptores Proteína Tirosina Quinases/genética , Transcriptoma , Proteínas ras/genética , Adenocarcinoma/etiologia , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Adenocarcinoma de Pulmão , Adenocarcinoma Papilar/genética , Idoso , Idoso de 80 Anos ou mais , Substituição de Aminoácidos , Quinase do Linfoma Anaplásico , Brasil , Carcinoma de Células Acinares/genética , Intervalo Livre de Doença , Feminino , Deleção de Genes , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/etiologia , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Taxa de Mutação , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Prognóstico , Proteínas Proto-Oncogênicas p21(ras) , Fatores de Risco , Fumar/efeitos adversos , Análise de Sobrevida
3.
Lancet Oncol ; 14(5): 391-436, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23628188

RESUMO

Non-communicable diseases, including cancer, are overtaking infectious disease as the leading health-care threat in middle-income and low-income countries. Latin American and Caribbean countries are struggling to respond to increasing morbidity and death from advanced disease. Health ministries and health-care systems in these countries face many challenges caring for patients with advanced cancer: inadequate funding; inequitable distribution of resources and services; inadequate numbers, training, and distribution of health-care personnel and equipment; lack of adequate care for many populations based on socioeconomic, geographic, ethnic, and other factors; and current systems geared toward the needs of wealthy, urban minorities at a cost to the entire population. This burgeoning cancer problem threatens to cause widespread suffering and economic peril to the countries of Latin America. Prompt and deliberate actions must be taken to avoid this scenario. Increasing efforts towards prevention of cancer and avoidance of advanced, stage IV disease will reduce suffering and mortality and will make overall cancer care more affordable. We hope the findings of our Commission and our recommendations will inspire Latin American stakeholders to redouble their efforts to address this increasing cancer burden and to prevent it from worsening and threatening their societies.


Assuntos
Planejamento em Saúde , Programas Nacionais de Saúde/organização & administração , Neoplasias/prevenção & controle , Reforma dos Serviços de Saúde , Humanos , América Latina/epidemiologia , Modelos Organizacionais , Neoplasias/epidemiologia , Neoplasias/mortalidade , Melhoria de Qualidade , Índias Ocidentais/epidemiologia
5.
BMC Cancer ; 12: 507, 2012 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-23130941

RESUMO

BACKGROUND: PCA3 is a non-coding RNA (ncRNA) that is highly expressed in prostate cancer (PCa) cells, but its functional role is unknown. To investigate its putative function in PCa biology, we used gene expression knockdown by small interference RNA, and also analyzed its involvement in androgen receptor (AR) signaling. METHODS: LNCaP and PC3 cells were used as in vitro models for these functional assays, and three different siRNA sequences were specifically designed to target PCA3 exon 4. Transfected cells were analyzed by real-time qRT-PCR and cell growth, viability, and apoptosis assays. Associations between PCA3 and the androgen-receptor (AR) signaling pathway were investigated by treating LNCaP cells with 100 nM dihydrotestosterone (DHT) and with its antagonist (flutamide), and analyzing the expression of some AR-modulated genes (TMPRSS2, NDRG1, GREB1, PSA, AR, FGF8, CdK1, CdK2 and PMEPA1). PCA3 expression levels were investigated in different cell compartments by using differential centrifugation and qRT-PCR. RESULTS: LNCaP siPCA3-transfected cells significantly inhibited cell growth and viability, and increased the proportion of cells in the sub G0/G1 phase of the cell cycle and the percentage of pyknotic nuclei, compared to those transfected with scramble siRNA (siSCr)-transfected cells. DHT-treated LNCaP cells induced a significant upregulation of PCA3 expression, which was reversed by flutamide. In siPCA3/LNCaP-transfected cells, the expression of AR target genes was downregulated compared to siSCr-transfected cells. The siPCA3 transfection also counteracted DHT stimulatory effects on the AR signaling cascade, significantly downregulating expression of the AR target gene. Analysis of PCA3 expression in different cell compartments provided evidence that the main functional roles of PCA3 occur in the nuclei and microsomal cell fractions. CONCLUSIONS: Our findings suggest that the ncRNA PCA3 is involved in the control of PCa cell survival, in part through modulating AR signaling, which may raise new possibilities of using PCA3 knockdown as an additional therapeutic strategy for PCa control.


Assuntos
Antígenos de Neoplasias/metabolismo , Neoplasias da Próstata/metabolismo , RNA não Traduzido/metabolismo , Receptores Androgênicos/metabolismo , Antígenos de Neoplasias/genética , Linhagem Celular Tumoral , Sobrevivência Celular/genética , Humanos , Immunoblotting , Masculino , Neoplasias da Próstata/genética , RNA Interferente Pequeno , RNA não Traduzido/genética , Reação em Cadeia da Polimerase em Tempo Real , Receptores Androgênicos/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/genética , Transfecção
6.
Toxicol Pathol ; 40(5): 731-41, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22549973

RESUMO

The development of bleomycin-induced pulmonary fibrosis (BLEO-PF) has been associated with differences in genetic background and oxidative stress status. The authors' aim was to investigate the crosstalk between the redox profile, lung histology, and respiratory function in BLEO-PF in C57BL/6, DBA/2, and BALB/c mice. BLEO-PF was induced with a single intratracheal dose of bleomycin (0.1 U/mouse). Twenty-one days after bleomycin administration, the mortality rate was over 50% in C57BL/6 and 20% in DBA/2 mice, and BLEO-PF was not observed in BALB/c. There was an increase in lung static elastance (p < .001), viscoelastic/inhomogeneous pressure (p < .05), total pressure drop after flow interruption (p < .01), and ΔE (p < .05) in C57BL/6 mice. The septa volume increased in C57BL/6 (p < .05) and DBA/2 (p < .001). The levels of IFN-γ were reduced in C57BL/6 mice (p < .01). OH-proline levels were increased in C57BL/6 and DBA/2 mice (p < .05). SOD activity and expression were reduced in C57BL/6 and DBA/2 mice (p < .001 and p < .001, respectively), whereas catalase was reduced in all strains 21 days following bleomycin administration compared with the saline groups (C57BL/6: p < .05; DBA/2: p < .01; BALB/c: p < .01). GPx activity and GPx1/2 expression decreased in C57BL/6 (p < .001). The authors conclude that BLEO-PF resistance may also be related to the activity and expression of SOD in BALB/c mice.


Assuntos
Bleomicina/efeitos adversos , Estresse Oxidativo , Fibrose Pulmonar/patologia , Fenômenos Fisiológicos Respiratórios/efeitos dos fármacos , Animais , Bleomicina/metabolismo , Regulação da Expressão Gênica , Glutationa Peroxidase/metabolismo , Pulmão/efeitos dos fármacos , Pulmão/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Oxirredução , Fibrose Pulmonar/induzido quimicamente , Superóxido Dismutase/metabolismo , Glutationa Peroxidase GPX1
7.
Mol Cancer ; 10: 151, 2011 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-22185378

RESUMO

BACKGROUND: Clinical studies have shown antineoplastic effectiveness of monoclonal antibodies (MAbs) against EGFR for different indications. Several MAbs directed to EGFR were developed recently, such as matuzumab, but there is still lack of information on preclinical data on its combination with chemo-radiation. Thus, the present study intended to examine the molecular pathways triggered by matuzumab alone or associated to chemo-radiotherapy in gynecological cell lines and its impact on cell growth and signaling. RESULTS: Combination of matuzumab with radiation and cisplatin did not enhance its cytostatic effects on A431, Caski and C33A cells (high, intermediate and low EGFR expression, respectively) in clonogenic assays, when compared to controls. The lack of effect was mediated by persistent signaling through EGFR due to its impaired degradation. In spite of the fact that matuzumab inhibited phosphorylation of EGFR, it had no effect upon cell viability. To analyze which downstream molecules would be involved in the EGFR signaling in the presence of matuzumab, we have tested it in combination with either PD98059 (MAPK inhibitor), or LY294002 (PI3K inhibitor). Matuzumab exhibited a synergic effect with LY294002, leading to a reduction of Akt phosphorylation that was followed by a decrease in A431 and Caski cells survival. The combination of PD98059 and matuzumab did not show the same effect suggesting that PI3K is an important effector of EGFR signaling in matuzumab-treated cells. Nonetheless, matuzumab induced ADCC in Caski cells, but not in the C33A cell line, suggesting that its potential therapeutic effects in vitro are indeed dependent on EGFR expression. CONCLUSIONS: Matuzumab combined with chemoradiation did not induce cytotoxic effects on gynecological cancer cell lines in vitro, most likely due to impaired EGFR degradation. However, a combination of matuzumab and PI3K inhibitor synergistically inhibited pAkt and cell survival, suggesting that the use of PI3K/Akt inhibitors could overcome intrinsic resistance to matuzumab in vitro. Altogether, data presented here can pave the way to a rational design of clinical strategies in patients with resistant profile to anti-EGFR inhibitors based on combination therapy.


Assuntos
Anticorpos Monoclonais Humanizados/farmacologia , Antineoplásicos/farmacologia , Resistencia a Medicamentos Antineoplásicos , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular , Regulação para Baixo , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/metabolismo , Humanos , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais
8.
Anal Biochem ; 415(2): 203-5, 2011 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-21596015

RESUMO

Cell death by apoptosis triggers the engagement of a conserved intracellular machinery of execution, involving mainly the activation of the caspase family of cysteine proteases. Caspase-3 is a common effector of most of the apoptotic pathways and is able to cleave several target proteins whose degradation will contribute to the execution phase of the cell demise program. Here we present a modification of the Western blot protocol to improve sensitivity of caspase-3 detection, providing a valuable tool to access its activation in biological specimens.


Assuntos
Western Blotting/métodos , Caspase 3/análise , Glutaral/química , Anticorpos/imunologia , Antineoplásicos/farmacologia , Caspase 3/imunologia , Caspase 3/metabolismo , Linhagem Celular Tumoral , Humanos , Imunoensaio/métodos , Proteínas Recombinantes/análise , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/metabolismo
9.
Inhal Toxicol ; 23(14): 918-26, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22122305

RESUMO

The aim of the present study was to investigate the involvement of oxidative stress in acute lung injury (ALI) induced by lipopolysaccharide (LPS) and its effects upon cell structure, function and inflammation. In total, 108 male C57BL/6 mice were divided into seven groups: CTR Group (50 µL of saline) administered intratracheally (i.t.), LPS 6 h (10 µg of LPS - i.t.), LPS 12 h (10 µg of LPS - i.t.), LPS 24 h (10 µg of LPS - i.t.), LPS 48 h (10 µg of LPS - i.t.), LPS 24 h (10 µg - i.t.) + NAC 40 mg/kg (gavage) and 24 h LPS (10 µg - i.t.) + NAC 100 mg/kg (gavage). The antioxidant treatment protected the lungs from stress in the first 12 h, but significant oxidative stress induction was observed at the 24-hour time point, and, after 48 h, there was no protection exerted by the antioxidant treatment. NAC (N-acetylcysteine) reversed the elastance parameters, and ΔP1 and ΔP2 compared with 24 h LPS alone. NAC reduced the number of inflammatory cells in histology analysis when compared with the 24 h LPS alone-treated group. NAC also inhibited the transcription of NFκB, IL-6, TNF-α and COX2 usually induced by LPS. Our results suggest that oxidative stress plays an important role in structural, functional and inflammatory responses in the ALI model.


Assuntos
Acetilcisteína/farmacologia , Lesão Pulmonar Aguda/induzido quimicamente , Antioxidantes/farmacologia , Lipopolissacarídeos/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Lesão Pulmonar Aguda/patologia , Lesão Pulmonar Aguda/fisiopatologia , Animais , Líquido da Lavagem Broncoalveolar/química , Líquido da Lavagem Broncoalveolar/citologia , Catalase/metabolismo , Citocinas/genética , Modelos Animais de Doenças , Expressão Gênica/efeitos dos fármacos , Glutationa/metabolismo , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Masculino , Malondialdeído/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Nitritos/metabolismo , Oxirredução , Peroxidase/metabolismo , Superóxido Dismutase/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
10.
Rev Assoc Med Bras (1992) ; 66(3): 338-344, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32520155

RESUMO

The first confirmed case of coronavirus disease 2019 (COVID-19) in Brasil was reported on February 25th, 2020, and by April 3rd, 8076 were confirmed in the country. As COVID-19 disease incidence escalates in Brasil, management of cancer patients requires immediate action and oncology clinics are urged to establish a contingency plan. We have installed a COVID-19 Management Committee to elaborate and implement best practices to assist cancer outpatients as well as to provide a safe environment for clinical staff and other employees at the outpatient clinics. The challenges of cancer treatment in the midst of COVID-19 global pandemic highlight the importance of a rapid response by institutions, where organizational structure, strategic planning, agility in guidelines implementation and alternative ways to protect and support clinical staff, employees and patients may be the key to mitigate pandemic effects.


Assuntos
Betacoronavirus , Infecções por Coronavirus/prevenção & controle , Oncologia/normas , Neoplasias/terapia , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Brasil , COVID-19 , Humanos , Oncologia/métodos , Oncologia/organização & administração , Gestão de Riscos , SARS-CoV-2
11.
J Glob Oncol ; 5: 1-9, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31770067

RESUMO

PURPOSE: Physicians rarely receive formal training in leadership skills. Çitaku and colleagues have identified a set of leadership competencies (LCs) providing validity evidence in North American (NA) and European Union (EU) medical education institutions. We aim to apply this same survey to a sample of Latin American (LA) medical leaders from the oncology community and related areas, compare the results with those of the previous survey, and perform subgroup analyses within the LA cohort. METHODS: The survey was sent to nearly 8,000 physicians of participating professional organizations. In addition to the 63 questions, we also collected data on the type of institution, country, specialty, sex, age, years of experience in oncology, and leadership position. RESULTS: The 217 LA respondents placed the highest value on task management competencies (91.37% reported these as important or very important v 87.0% of NA/EU respondents; P < .0001), followed by self-management (87.45% of LA respondents v 87.55% of NA/EU respondents; P = not significant [NS]), social responsibility (86.83% of LA respondents v 87.48% of NA/EU respondents; P = NS), innovation (86.69% of LA respondents v 85.31% of NA/EU respondents; P = NS), and leading others (83.31% of LA respondents v 84.71% of NA/EU respondents; P = NS). Social responsibility, which was first in importance in the NA/EU survey, was only third in the LA survey. Subgroup analyses showed significant variations in the ratings of specific LCs within the LA population. CONCLUSION: LCs valued by LA leaders somewhat differ from those valued by their NA and EU counterparts, implying that cultural aspects might influence the perception of desired LCs. We also detected variations in the responses within the LA population. Our data indicate that current physician leadership training programs should be tailored to suit specific needs and cultural aspects of each region. Further validity studies of this instrument with other samples and cultures are warranted.


Assuntos
Educação Médica , Liderança , Médicos , Competência Profissional , Comparação Transcultural , Inteligência Emocional , Europa (Continente) , Feminino , Humanos , América Latina , Masculino , Pessoa de Meia-Idade , América do Norte , Inquéritos e Questionários
12.
Oncotarget ; 9(55): 30594-30609, 2018 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-30093972

RESUMO

Cisplatin-based chemoradiation is the standard treatment for cervical cancer, but chemosensitizing strategies are needed to improve patient survival. EGFR (Epidermal Growth Factor Receptor) is an oncogene overexpressed in cervical cancer that is involved in chemoresistance. Recent studies showed that EGFR upregulates multiple elements of the coagulation cascade, including tissue factor (TF) and the protease-activated receptors (PAR) 1 and 2. Moreover, many G protein-coupled receptors, including PARs, have been implicated in EGFR transactivation. However, the role of coagulation proteins in the progression of cervical cancer has been poorly investigated. Herein we employed cervical cancer cell lines and The Cancer Genome Atlas (TCGA) database to evaluate the role of EGFR, TF and PAR2 in chemoresistance. The SLIGKL-NH2 peptide (PAR2-AP) and coagulation factor VIIa (FVIIa) were used as PAR2 agonists, while cetuximab was used to inhibit EGFR. The more aggressive cell line CASKI showed higher expression levels of EGFR, TF and PAR2 than that of C33A. PAR2 transactivated EGFR, which further upregulated cyclooxygenase-2 (COX2) expression. PAR2-AP decreased cisplatin-induced apoptosis through an EGFR- and COX2-dependent mechanism. Furthermore, treatment of CASKI cells with EGF upregulated TF expression, while treatment with cetuximab decreased the TF protein levels. The RNA-seq data from 309 TCGA samples showed a strong positive correlation between EGFR and TF expression (P = 0.0003). In addition, the increased expression of EGFR, PAR2 or COX2 in cervical cancer patients was significantly correlated with poor overall survival. Taken together, our results suggest that EGFR and COX2 are effectors of the TF/FVIIa/PAR2 signaling pathway, promoting chemoresistance.

13.
Pharmacol Rep ; 70(3): 409-417, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29627688

RESUMO

BACKGROUND: Epithelial ovarian cancer (EOC) remains the most lethal gynecologic malignancy. Primary cytoreductive surgery with adjuvant taxane-platinum chemotherapy is the standard treatment to fight ovarian cancer, however, their side effects are severe, and chemoresistance emerges at high rates. Therefore, EOC clinic urges for novel treatment strategies to reverse chemoresistance and to improve the survival rates. Metformin has been shown to act in synergy with certain anti-cancer agents, overcoming chemoresistance in various types of tumors. This paper aims to investigate the use of metformin as a new treatment option for cisplatin- and paclitaxel-resistant ovarian cancer. METHODS: The effects of metformin alone or in combination with conventional drugs on resistant EOC cell lines were investigated using the MTT assay for cell proliferation; Flow Cytometry analysis for cell cycle and the mRNA expression was analyzed using the real-time PCR technique. RESULTS: We found that metformin exhibited antiproliferative effects in paclitaxel-resistant A2780-PR, and in cisplatin-resistant ACRP cell lines. The combined therapy containing conventional drugs and metformin improved the effect of the treatment in cell proliferation rate, especially in the resistant cells. We found that metformin, in clinical relevant doses, could significantly reduce the mRNA expression of inflammatory cytokines and NF-κB signaling pathway. CONCLUSIONS: Taken together, our observations suggest that metformin inhibits the inflammatory pathway induced by paclitaxel and cisplatin treatment. Furthermore, metformin in combination with paclitaxel or cisplatin improved the sensitivity in drug-resistant ovarian cancer cells. Therefore, metformin may be beneficial treatment strategy, particularly in patients with tumors refractory to platinum and taxanes.


Assuntos
Antineoplásicos/farmacologia , Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Metformina/farmacologia , Neoplasias Ovarianas/tratamento farmacológico , Paclitaxel/farmacologia , Carcinoma Epitelial do Ovário , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , NF-kappa B/metabolismo , Neoplasias Epiteliais e Glandulares/tratamento farmacológico , Neoplasias Epiteliais e Glandulares/metabolismo , Neoplasias Ovarianas/metabolismo , Transdução de Sinais/efeitos dos fármacos , Taxa de Sobrevida
14.
Rev Assoc Med Bras (1992) ; 63(1): 70-77, 2017 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-28225882

RESUMO

INTRODUCTION: Patients who are treating cancer have often used alternative therapies. In the internet era, information can be broadcasted widely, and this happened with phosphoethanolamine in Brazil, where this substance was claimed by the population to be the "cure for cancer." METHOD: This is a cross-sectional study developed by the Brazilian Society of Clinical Oncology (SBOC). An objectively structured questionnaire was sent by e-mail and SMS to active MDs members of the SBOC. Descriptive statistics was used to evaluate the data. Statistical significance between the variables was tested by Pearson's Chi-squared test (p<0.05 was considered significance). RESULTS: The survey was sent to 1,072 oncologists, and 398 (37.1%) answered at least part of it. One hundred and fifteen (28.9%) had followed patients who had used phosphoethanolamine. Among these, 14 (12.2%) observed adverse events and four (3.5%) attributed clinical benefit to the substance. Most of the oncologists (n=331; 83.2%) believe that it should only be used as part of a clinical trial protocol. Most physicians did not recommend this drug to their patients (n=311; 78.1%). Oncologists in Southeast, South and Midwest Brazil were more likely to have patients taking the drug compared to the Northern and Northeastern regions. CONCLUSION: This is the first survey to assess the opinion and experience of oncologists about this alternative therapy. Most oncologists in Brazil do not believe that synthetic phosphoethanolamine is active in cancer treatment, do not recommend its use without proper evaluation, and state that it should only be available to patients in the context of clinical trials.


Assuntos
Antineoplásicos/uso terapêutico , Etanolaminas/uso terapêutico , Oncologistas/estatística & dados numéricos , Padrões de Prática Médica , Brasil , Distribuição de Qui-Quadrado , Terapias Complementares/estatística & dados numéricos , Estudos Transversais , Drogas em Investigação , Feminino , Humanos , Masculino , Sociedades Médicas , Inquéritos e Questionários
15.
Oncol Rep ; 38(1): 402-410, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28560416

RESUMO

The process of lung carcinogenesis is still not well understood and involves different levels of regulation of several genes. The search for molecular biomarkers, which can be applicable to clinical practice, has been the focus of various studies. XIAP-associated factor 1 (XAF1) was previously shown to be downregulated in many types of tumors, including squamous cell lung cancer. XAF1 is a pro-apoptotic protein and its restoration was found to sensitize cancer cells to apoptotic stimuli; however, the precise mechanism involved in the downregulation of XAF1 in tumors is unknown and promoter hypermethylation or heat-shock transcription factor 1 (HSF1) may be involved. Therefore, the aim of the present study was to evaluate the expression of XAF1 in tumors and adjacent non-tumor specimens from non-small cell lung cancer (NSCLC) patients, and its potential association with various factors including clinicopathological characteristics and other genes involved in NSCLC. Our results indicated that XAF1 expression was markedly altered in NSCLC tumor samples when compared to that found in normal lung tissues. Predominantly, XAF1 was downregulated in the tumors, except in never-smoker patients. In addition, XAF1 may also be important in the whole cell stress mechanism where the p53 status is crucial.


Assuntos
Carcinogênese/patologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma de Células Escamosas/patologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Neoplasias Pulmonares/patologia , Proteínas de Neoplasias/metabolismo , Proteínas Adaptadoras de Transdução de Sinal , Adulto , Idoso , Apoptose , Proteínas Reguladoras de Apoptose , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Metilação de DNA , Regulação para Baixo , Feminino , Fatores de Transcrição de Choque Térmico/metabolismo , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Regiões Promotoras Genéticas/genética , Estudos Prospectivos , Proteína Supressora de Tumor p53/metabolismo
16.
Mol Clin Oncol ; 6(4): 494-502, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28413655

RESUMO

The enzyme cyclooxygenase 2 (COX-2) is known to be involved in tumorigenesis and metastasis in certain types of cancer. Nevertheless, the prognostic value of COX-2 overexpression and its polymorphisms in patients with non-small cell lung cancer (NSCLC) have yet to be fully elucidated. The aim of the present study was to investigate the association between the three most commonly studied COX-2 gene polymorphisms (-1195 G/A, -765 G/C and 8473 T/C) with COX-2 expression and lung cancer risk in a Brazilian cohort. In the present hospital based, case-control retrospective study, 104 patients with NSCLC and 202 cancer free control subjects were genotyped for -1195 G/A, -765 G/C and 8473 T/C polymorphisms using allelic discrimination with a reverse transcription quantitative polymerase chain reaction method. COX-2 mRNA expression was analyzed in surgically resected tumors from 34 patients with NSCLC. The results revealed that COX-2 expression levels were higher in tumor tissue compared with normal lung tissue. However, this overexpression of COX-2 was not associated with the patient outcome, and furthermore, none of the analyzed polymorphisms were associated with the risk of developing lung cancer, COX-2 overexpression, or the overall survival of the patients with NSCLC. Taken together, the findings described in the present study do not support a major role for COX-2 polymorphisms and COX-2 overexpression in lung carcinogenesis within the Brazilian population.

17.
Leuk Res ; 30(5): 583-95, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16249029

RESUMO

MicroRNAs (miRNAs) are abundant small regulatory RNAs with multiple roles in cell fate determination. The processes regulating cellular miRNA levels are still unclear and experimental oligonucleotide tools to readily mimic their effects are not yet available. Here, we report that thapsigargin-induced intracellular Ca(++) release suppressed pre-miR-181a levels in human promegakaryotic Meg-01 cells, induced differentiation-associated nuclear endoreduplication and caspase-3 activation and replaced the acetylcholinesterase 3' splice variant AChE-S with AChE-R. AChE, PKC and PKA inhibitors all attenuated the pre-miR-181a decline and the induced differentiation. AChmiON, a synthetic 23-mer 2'-oxymethylated oligonucleotide mimicking the miR-181a sequence, blocked the calcium-induced differentiation while elevating cellular pre-miR-181a levels and inducing DNA fragmentation and cell death. Moreover, when added to RW 264.7 macrophages, AChmiON at 100 nM induced nitric oxide production with efficiency close to that of bacterial endotoxin, demonstrating physiologically relevant activities also in blood-born monocytes/macrophages. The stress-induced modulation of hematopoietic miR-181a levels through AChE, PKC and PKA cascade(s) suggests using miRNA mimics for diverting the fate of hematopoietic tumor cells towards differentiation and/or apoptosis.


Assuntos
Acetilcolinesterase/metabolismo , Megacariócitos/metabolismo , MicroRNAs/metabolismo , Oligonucleotídeos/farmacologia , Acetilcolinesterase/efeitos dos fármacos , Acetilcolinesterase/genética , Animais , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Cálcio/metabolismo , Cálcio/farmacologia , Caspase 3 , Caspases/efeitos dos fármacos , Caspases/metabolismo , Diferenciação Celular/efeitos dos fármacos , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Células Cultivadas , Proteínas Quinases Dependentes de AMP Cíclico/antagonistas & inibidores , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Inibidores Enzimáticos/farmacologia , Humanos , Macrófagos/efeitos dos fármacos , Megacariócitos/efeitos dos fármacos , Camundongos , MicroRNAs/efeitos dos fármacos , MicroRNAs/genética , Óxido Nítrico/biossíntese , Oligonucleotídeos/síntese química , Proteína Quinase C/antagonistas & inibidores , Proteína Quinase C/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Tapsigargina/antagonistas & inibidores , Tapsigargina/farmacologia
18.
Cancer Res ; 76(11): 3189-99, 2016 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-27197187

RESUMO

Activating mutations of K-ras are the most common oncogenic alterations found in lung cancer. Unfortunately, attempts to target K-ras-mutant lung tumors have thus far failed, clearly indicating the need for new approaches in patients with this molecular profile. We have previously shown NF-κB activation, release of IL6, and activation of its responsive transcription factor STAT3 in K-ras-mutant lung tumors, which was further amplified by the tumor-enhancing effect of chronic obstructive pulmonary disease (COPD)-type airway inflammation. These findings suggest an essential role for this inflammatory pathway in K-ras-mutant lung tumorigenesis and its enhancement by COPD. Therefore, here we blocked IL6 using a monoclonal anti-IL6 antibody in a K-ras-mutant mouse model of lung cancer in the absence or presence of COPD-type airway inflammation. IL6 blockade significantly inhibited lung cancer promotion, tumor cell-intrinsic STAT3 activation, tumor cell proliferation, and angiogenesis markers. Moreover, IL6 inhibition reduced expression of protumor type 2 molecules (arginase 1, Fizz 1, Mgl, and IDO), number of M2-type macrophages and granulocytic myeloid-derived suppressor cells, and protumor T-regulatory/Th17 cell responses. This was accompanied by increased expression of antitumor type 1 molecule (Nos2), and antitumor Th1/CD8 T-cell responses. Our study demonstrates that IL6 blockade not only has direct intrinsic inhibitory effect on tumor cells, but also reeducates the lung microenvironment toward an antitumor phenotype by altering the relative proportion between protumor and antitumor immune cells. This information introduces IL6 as a potential druggable target for prevention and treatment of K-ras-mutant lung tumors. Cancer Res; 76(11); 3189-99. ©2016 AACR.


Assuntos
Anticorpos Monoclonais/farmacologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Interleucina-6/antagonistas & inibidores , Neoplasias Pulmonares/patologia , Mutação/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Microambiente Tumoral/efeitos dos fármacos , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/genética , Adenocarcinoma/patologia , Animais , Apoptose , Western Blotting , Carcinogênese , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Proliferação de Células , Modelos Animais de Doenças , Progressão da Doença , Humanos , Técnicas Imunoenzimáticas , Interleucina-6/genética , Interleucina-6/imunologia , Interleucina-6/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Camundongos , NF-kappa B/genética , NF-kappa B/metabolismo , Estadiamento de Neoplasias , Prognóstico , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Doença Pulmonar Obstrutiva Crônica/genética , Doença Pulmonar Obstrutiva Crônica/patologia , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Taxa de Sobrevida , Células Tumorais Cultivadas
19.
Rev. Assoc. Med. Bras. (1992, Impr.) ; 66(3): 338-344, Mar. 2020. graf
Artigo em Inglês | SES-SP, LILACS | ID: biblio-1136202

RESUMO

SUMMARY The first confirmed case of coronavirus disease 2019 (COVID-19) in Brasil was reported on February 25th, 2020, and by April 3rd, 8076 were confirmed in the country. As COVID-19 disease incidence escalates in Brasil, management of cancer patients requires immediate action and oncology clinics are urged to establish a contingency plan. We have installed a COVID-19 Management Committee to elaborate and implement best practices to assist cancer outpatients as well as to provide a safe environment for clinical staff and other employees at the outpatient clinics. The challenges of cancer treatment in the midst of COVID-19 global pandemic highlight the importance of a rapid response by institutions, where organizational structure, strategic planning, agility in guidelines implementation and alternative ways to protect and support clinical staff, employees and patients may be the key to mitigate pandemic effects.


RESUMO O primeiro caso confirmado de Doença Associada ao Coronavírus 2019 (COVID-19) no Brasil foi confirmado em 25 de fevereiro de 2020 e em 3 de abril já haviam 8076 casos confirmados no país. A medida que a incidência de COVID-19 aumenta no Brasil, o tratamento de pacientes com câncer exige ação imediata e as clínicas oncológicas são instadas a estabelecer um plano de contingência. Instalamos um Comitê de Manejo de COVID-19 para elaborar e implementar as melhores práticas para ajudar pacientes ambulatoriais com câncer, bem como proporcionar um ambiente seguro para a equipe clínica e outros funcionários das clínicas ambulatoriais. Os desafios do tratamento do câncer em meio à pandemia global do COVID-19 destacam a importância de uma resposta rápida das instituições, onde a estrutura organizacional, o planejamento estratégico, a agilidade na implementação de diretrizes e formas alternativas de proteger e apoiar a equipe clínica, funcionários e pacientes podem ser a chave para mitigar os efeitos da pandemia.


Assuntos
Humanos , Pneumonia Viral/prevenção & controle , Infecções por Coronavirus/prevenção & controle , Pandemias/prevenção & controle , Betacoronavirus , Oncologia/normas , Neoplasias/terapia , Gestão de Riscos , Brasil , Infecções por Coronavirus , Oncologia/métodos , Oncologia/organização & administração
20.
Cancer Treat Rev ; 40(4): 548-57, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24360358

RESUMO

Although the inhibition of angiogenesis is an established modality of cancer treatment, concerns regarding toxicity and drug resistance still constitute barriers to be overcome. For almost a decade since the approval of bevacizumab in 2004, the efforts on antiangiogenic therapeutics have been mainly focused in inhibiting the VEGF pathway. The ongoing understanding of the complexity of the angiogenic process has broadened the spotlight to include concurrent and downstream players to the list of targeted inhibitors. In this review, we summarize the currently existing and the promising antiangiogenic treatments, envisioning an apparent evolutionary trend towards the development of angiogenesis inhibitors of three modalities: single-target, multi-target, and broad-spectrum agents. The clinical efficacy and some structural aspects of monoclonal antibodies, small molecules, endogenous and synthetic angiogenesis inhibitors and their molecular targets are discussed, and the targeting of endothelial cells with the use of cytotoxic drugs in a metronomic schedule is appraised. The reader is invited to revisit current expectations about antiangiogenic therapy in an attempt to set consistent clinical endpoints from which patients could gain real and lasting clinical benefits.


Assuntos
Inibidores da Angiogênese/farmacologia , Neoplasias/irrigação sanguínea , Neoplasias/tratamento farmacológico , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Inibidores da Angiogênese/uso terapêutico , Animais , Humanos , Neovascularização Patológica/tratamento farmacológico
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