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1.
Invest New Drugs ; 38(1): 70-78, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31102120

RESUMO

Purpose Among alkaloids, abundant secondary metabolites in plants, aporphines constitute a class of compounds with interesting biological activities, including anticancer effects. The present study evaluated the anticancer activities of 14 substances, including four aporphine derivatives acquired through the biomonitoring of (±)-apomorphine hydrochloride total synthesis from 2-phenethylamine and 3,4-dimethoxybenzaldehyde against head and neck squamous cell carcinoma (HNSCC). Methods The cytotoxic effects of compounds against a panel of HNSCC cell lines were determined by PrestoBlue cell viability assay, while the genotoxicity of substances was evaluated by micronucleus test. Cell death was detected by flow cytometry (Annexin V/7AAD) and western blot analysis was used to detect the presence of cleaved Caspase-3 molecules. Results The aporphine and isoquinoline derivatives APO, C1, and A5 significantly reduced HNSCC cell viability and promoted DNA damages in these cells. Further, by activating the Caspase-3 pathway, these substances were able to induce apoptosis. Conclusion Our results revealed that APO, C1, and A5 exhibit cytotoxic effects in HNSCC cells. The mechanisms of action appear to be partly via the generation of DNA damages and apoptosis induction through Caspase-3 pathway activation. This study provides preclinical data that suggest a potential therapeutic role for APO, C1, and A5 against head and neck cancer cells.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Aporfinas/química , Neoplasias de Cabeça e Pescoço/patologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Antineoplásicos Fitogênicos/química , Apoptose , Aporfinas/farmacologia , Caspase 3/metabolismo , Proliferação de Células , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/metabolismo , Humanos , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo , Células Tumorais Cultivadas
2.
Carcinogenesis ; 40(12): 1452-1461, 2019 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-31436806

RESUMO

Management of locally advanced head and neck squamous cell carcinoma (HNSCC) requires a multi-prong approach comprising surgery, radiation and/or chemotherapy, yet outcomes are limited. This is largely due to a paucity of biomarkers that can predict response to specific treatment modalities. Here, we evaluated TGFß3 protein levels in extracellular vesicles (EVs) released by HNSCC cells as a predictor for response to chemoradiation therapy (CRT). To this end, specific EV-fractions were isolated from cell lines or HNSCC patient plasma, and TGFß3 protein was quantified. In patients treated with CRT, TGFß3 levels were found to be significantly higher in plasma EV-fractions or non-responders compared with responders. High levels of TGFß3 levels in Annexin V-EVs were associated with the worst progression-free survival. In vitro experiments demonstrated that TGFß3 silencing sensitized HNSCC cells to cytotoxic therapies, and this phenotype could be rescued by treatment with exogenous. In addition, specific EV-fractions shed by cisplatin-resistant cells were sufficient to transfer the resistant phenotype to sensitive cells through activation of TGFß-signaling pathway. Therefore, our data show that TGFß3 transmitted through EV plays a significant role in response to cytotoxic therapy, which can be exploited as a potential biomarker for CRT response in HNSCC patients treated with curative intent.


Assuntos
Biomarcadores Tumorais/sangue , Vesículas Extracelulares/metabolismo , Neoplasias de Cabeça e Pescoço/terapia , Carcinoma de Células Escamosas de Cabeça e Pescoço/terapia , Fator de Crescimento Transformador beta3/sangue , Adulto , Idoso , Quimiorradioterapia/métodos , Cisplatino/administração & dosagem , Resistencia a Medicamentos Antineoplásicos/fisiologia , Feminino , Neoplasias de Cabeça e Pescoço/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Paclitaxel/administração & dosagem , Tolerância a Radiação/fisiologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/sangue
3.
BMC Cancer ; 19(1): 373, 2019 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-31014274

RESUMO

BACKGROUND: There is a paucity of plasma-based biomarkers that prospectively segregate the outcome of patients with head and neck squamous-cell carcinoma (HNSCC) treated with chemoradiation therapy (CRT). Plasma extracellular vesicles (EVs) might be an alternative source for discovery of new specific markers present in patients with HNSCC, which could help to re-direct patients to appropriate curative therapies without delay. METHODS: In order to identify new markers in plasma compartments, Cholerae toxin B chain (CTB) and Annexin V (AV) were used to isolate EVs from pooled plasma samples from patients with locally advanced HNSCC who responded (CR, n = 6) or presented incomplete response (NR, n = 6) to CRT. The crude plasma and EVs cargo were screened by antibody array. RESULTS: Of the 370 polypeptides detected, 119 proteins were specific to NR patients while 38 were exclusive of the CR subjects. The Gene Set Enrichment Analysis (GSEA) and Search Tool for the Retrieval of Interacting Genes (STRING) database analysis indicated that the content of circulating plasma EVs might have a relevant function for the tumor intercellular communication in the HNSCC patients. CONCLUSION: This study provides a list of potential markers present in plasma compartments that might contribute to the development of tools for prediction and assessment of CRT response and potentially guide therapeutic decisions in this context.


Assuntos
Biomarcadores Tumorais/sangue , Carcinoma de Células Escamosas/patologia , Quimiorradioterapia/métodos , Vesículas Extracelulares/metabolismo , Neoplasias de Cabeça e Pescoço/patologia , Adulto , Idoso , Carcinoma de Células Escamosas/sangue , Carcinoma de Células Escamosas/terapia , Ensaios Clínicos Fase II como Assunto , Vesículas Extracelulares/patologia , Feminino , Seguimentos , Neoplasias de Cabeça e Pescoço/sangue , Neoplasias de Cabeça e Pescoço/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Análise Serial de Proteínas , Mapas de Interação de Proteínas
4.
BMC Med ; 13: 108, 2015 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-25956054

RESUMO

BACKGROUND: The presence of metastatic disease in cervical lymph nodes of head and neck squamous cell carcinoma (HNSCC) patients is a very important determinant in therapy choice and prognosis, with great impact in overall survival. Frequently, routine lymph node staging cannot detect occult metastases and the post-surgical histologic evaluation of resected lymph nodes is not sensitive in detecting small metastatic deposits. Molecular markers based on tissue-specific microRNA expression are alternative accurate diagnostic markers. Herein, we evaluated the feasibility of using the expression of microRNAs to detect metastatic cells in formalin-fixed paraffin-embedded (FFPE) lymph nodes and in fine-needle aspiration (FNA) biopsies of HNSCC patients. METHODS: An initial screening compared the expression of 667 microRNAs in a discovery set comprised by metastatic and non-metastatic lymph nodes from HNSCC patients. The most differentially expressed microRNAs were validated by qRT-PCR in two independent cohorts: i) 48 FFPE lymph node samples, and ii) 113 FNA lymph node biopsies. The accuracy of the markers in identifying metastatic samples was assessed through the analysis of sensitivity, specificity, accuracy, negative predictive value, positive predictive value, and area under the curve values. RESULTS: Seven microRNAs highly expressed in metastatic lymph nodes from the discovery set were validated in FFPE lymph node samples. MiR-203 and miR-205 identified all metastatic samples, regardless of the size of the metastatic deposit. Additionally, these markers also showed high accuracy when FNA samples were examined. CONCLUSIONS: The high accuracy of miR-203 and miR-205 warrant these microRNAs as diagnostic markers of neck metastases in HNSCC. These can be evaluated in entire lymph nodes and in FNA biopsies collected at different time-points such as pre-treatment samples, intraoperative sentinel node biopsy, and during patient follow-up. These markers can be useful in a clinical setting in the management of HNSCC patients from initial disease staging and therapy planning to patient surveillance.


Assuntos
Biomarcadores Tumorais/análise , Carcinoma de Células Escamosas/patologia , Neoplasias de Cabeça e Pescoço/patologia , Metástase Linfática/diagnóstico , MicroRNAs , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Carcinoma de Células Escamosas/genética , Feminino , Neoplasias de Cabeça e Pescoço/genética , Humanos , Linfonodos/patologia , Metástase Linfática/genética , Masculino , Pessoa de Meia-Idade , Prognóstico , Sensibilidade e Especificidade , Carcinoma de Células Escamosas de Cabeça e Pescoço
5.
J Transl Med ; 13: 262, 2015 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-26264462

RESUMO

PURPOSE: Definitive radiation therapy is the mainstay of treatment for early stage laryngeal squamous cell carcinoma (LSCC). However, up to 30% of the patients do not respond to radiotherapy. Unfortunately, we are unable to predict which tumors are likely to respond to radiation, and which will be resistant and persist. Therefore, the development of novel markers to predict response to radiotherapy is urgently needed. This study was designed to evaluate the expression pattern of microRNAs (miRNAs) in LSCC in order to identify markers capable of segregating radioresistant and radiosensitive tumors and to investigate the relationship between the expression of these miRNAs and the prognosis of LSCC. METHODS: The expression profile of 667 miRNAs was determined in an initial screening of nine early-stage LSCC samples (5 radioresistant and 4 radiosensitive) using TaqMan Low-Density Array (TLDA). Real-time polymerase chain reactions were performed to validate the expression of selected miRNAs in an expanded LSCC cohort (20 radioresistant and 14 radiosensitive). The miRNA expression level was scored as high or low based on the median of the expression in the LSCC samples. RESULTS: A comprehensive miRNA expression profiling enabled the identification of four miRNAs (miR-296-5p miR-452, miR-183* and miR-200c) differentially expressed in radioresistant LSCC. Moreover, the analysis of additional 34 LSCC samples, confirmed the expression of miR-296-5p as significantly related to radioresistance (p = 0.002) as well as an association of this marker with recurrence (p = 0.025) in early stage laryngeal cancer. CONCLUSIONS: This study indicates that miR-296-5p expression is associated with resistance to radiotherapy and tumor recurrence in early stage LSCC, showing the feasibility of this marker as a novel prognostic factor for this malignance. Furthermore, miR-296-5p expression could be helpful in the identification of tumors resistant to radiotherapy; thus aiding the clinicians in the choice of the best therapeutic scheme to be used in each case.


Assuntos
Biomarcadores Tumorais/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Laríngeas/genética , Neoplasias Laríngeas/radioterapia , MicroRNAs/genética , Tolerância a Radiação/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Perfilação da Expressão Gênica , Humanos , Neoplasias Laríngeas/patologia , Masculino , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias de Células Escamosas/genética , Neoplasias de Células Escamosas/patologia , Neoplasias de Células Escamosas/radioterapia , Prognóstico , Análise de Sobrevida
6.
Carcinogenesis ; 34(1): 20-7, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23042095

RESUMO

Hypermethylation in the promoter regions of genes is associated with suppression of gene expression and has been considered a potential molecular marker for several tumor types, including head and neck squamous cell carcinomas (HNSCC). Moreover, hypermethylation can be detected in body fluids such as saliva and can be useful for the diagnosis and prognosis of patients suffering from cancer. To evaluate the hypermethylation profile as a tool for early detection of tumor recurrences, this study determines the methylation status of 24 genes in salivary rinses collected from HNSCC patients at diagnosis, just after the last curative treatment and in the patients' follow-up visit at 6 months after treatment. In the analysis of salivary rinse samples taken at diagnosis of HNSCC patients, five genes (CCNA1, DAPK, DCC, MGMT and TIMP3) showed high specificity and sensitivity. Hypermethylation in any of these five genes was correlated with the presence of tumors in the oral cavity. Patients with TIMP3 methylation in samples collected 6 months after the last curative treatment had lower local recurrence-free survival (P = 0.008). Multivariate analysis confirmed that this hypermethylation pattern remained as an independent prognostic factor for local recurrence (P = 0.025). This study presents, for the first time, the detection of TIMP3 promoter hypermethylation in post-treatment salivary rinse as an independent prognostic maker for local recurrence-free survival in patients with HNSCC, justifying the use of DNA hypermethylation detection in saliva as a tool for identifying and monitoring HNSCC patients' subgroups with high risk of developing local recurrence.


Assuntos
Carcinoma de Células Escamosas/genética , Metilação de DNA , Neoplasias de Cabeça e Pescoço/genética , Saliva/metabolismo , Inibidor Tecidual de Metaloproteinase-3/genética , Carcinoma de Células Escamosas/patologia , Feminino , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Prognóstico , Recidiva
7.
J Transl Med ; 11: 316, 2013 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-24359512

RESUMO

BACKGROUND: Hypermethylation in the promoter regions is associated with the suppression of gene expression and has been considered a potential molecular marker for several tumor types, including head and neck squamous cell carcinomas (HNSCC). METHODS: To evaluate the gene hypermethylation profile as a prognostic marker, this retrospective study used a QMSP approach to determine the methylation status of 19 genes in 70 HNSCC patients. RESULTS: The methylation profile analysis of primary HNSCC revealed that genes CCNA1, DAPK, MGMT, TIMP3 and SFRP1 were frequently hypermethylated, with high specificity and sensitivity. TIMP3 and CCNA1 hypermethylation was significantly associated with lower rates of second primary tumor-free survival (p = 0.007 and p = 0.001; log-rank test, respectively). CONCLUSION: This study, for the first time, presents CCNA1 and TIMP3 hypermethylation as a helpful tool to identify HNSCC subjects at risk of developing second primary carcinomas.


Assuntos
Carcinoma de Células Escamosas/genética , Ciclina A1/genética , Metilação de DNA , Neoplasias de Cabeça e Pescoço/genética , Segunda Neoplasia Primária/genética , Inibidor Tecidual de Metaloproteinase-3/genética , Carcinoma de Células Escamosas/epidemiologia , Feminino , Neoplasias de Cabeça e Pescoço/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Segunda Neoplasia Primária/epidemiologia , Reação em Cadeia da Polimerase , Estudos Retrospectivos
8.
Sci Rep ; 12(1): 21113, 2022 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-36477472

RESUMO

Glioblastoma (GBM) is the most aggressive and common primary malignant brain tumor with limited available therapeutic approaches. Despite improvements in therapeutic options for GBM patients, efforts to develop new successful strategies remain as major unmet medical needs. Based on the cytotoxic properties of aporphine compounds, we evaluated the biological effect of 12 compounds obtained through total synthesis of ( ±)-apomorphine hydrochloride (APO) against GBM cells. The compounds 2,2,2-trifluoro-1-(1-methylene-3,4-dihydroisoquinolin-2(1H)-yl)ethenone (A5) and ( ±)-1-(10,11-dimethoxy-6a,7-dihydro-4H-dibenzo[de,g]quinolin-6(5H)-yl)ethenone (C1) reduced the viability of GBM cells, with 50% inhibitory concentration ranging from 18 to 48 µM in patient-derived GBM cultures. Our data show that APO, A5 or C1 modulate the expression of DNA damage and apoptotic markers, impair 3D-gliomasphere growth and reduce the expression of stemness markers. Potential activity and protein targets of A5, C1 or APO were predicted in silico based on PASS and SEA software. Dopamine receptors (DRD1 and 5), CYP2B6, CYP2C9 and ABCB1, whose transcripts were differentially expressed in the GBM cells, were among the potential A5 or C1 target proteins. Docking analyses (HQSAR and 3D-QSAR) were performed to characterize possible interactions of ABCB1 and CYP2C9 with the compounds. Notably, A5 or C1 treatment, but not temozolomide (TMZ), reduced significantly the levels of extracellular ATP, suggesting ABCB1 negative regulation, which was correlated with stronger cytotoxicity induced by the combination of TMZ with A5 or C1 on GBM cells. Hence, our data reveal a potential therapeutic application of A5 and C1 as cytotoxic agents against GBM cells and predicted molecular networks that can be further exploited to characterize the pharmacological effects of these isoquinoline-containing substances.


Assuntos
Temozolomida , Humanos , Temozolomida/farmacologia
9.
Onco Targets Ther ; 14: 455-467, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33488100

RESUMO

INTRODUCTION: Multiple myeloma (MM) remains an incurable disease, and patient survival requires a better understanding of this malignancy's molecular aspects. Heparanase (HPSE) is highly expressed in aggressive MM cells and related to tumor growth, metastasis, and bortezomib (BTZ) resistance. Thus, targeting HPSE seems to be a promising approach for MM treatment, and because microRNAs (miRNAs) have emerged as potential regulators of HPSE expression, the use of extracellular vesicles (EVs) can allow the efficient delivery of therapeutic miRNAs. METHODS: We used prediction algorithms to identify potential miRNAs that regulate negatively HPSE expression. RT-qPCR was performed to assess miRNAs and HPSE expression in MM lines (U266 and RPMI-8226). Synthetic miRNA mimics were electroporated in MM cells to understand the miRNA contribution in HPSE expression, glycosaminoglycans (GAGs) profile, cell proliferation, and cell death induced by BTZ. EVs derived from HEK293T cells were engineered with miRNAs to evaluate their therapeutic potential combined with BTZ. RESULTS: It revealed a direct association between BTZ sensitivity, HPSE, and miR-1252-5p expressions. Moreover, overexpression of miR-1252-5p significantly reduced HPSE expression and HPSE enzymatic activity in MM cells. The higher level of miR-1252-5p was correlated with a reduction of cell viability and higher sensitivity to BTZ. Further, EVs carrying miR-1252-5p increased MM cells' sensitivity to BTZ treatment. CONCLUSION: These results showed that miR-1252-5p could negatively regulate HPSE in MM, indicating the use of EVs carrying miR-1252-5p as a potential novel BTZ sensitization approach in MM cells.

10.
Sci Rep ; 11(1): 16415, 2021 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-34385507

RESUMO

Evaluate the biological action of valproic acid in the acetylation of histones and in the methylation of tumor suppressor genes via oral rinse in patients with a previous history of head and neck squamous cell carcinoma (HNSCC). Forty-two active or former smokers were included in this randomized, double-blind, placebo-controlled trial. Oral rinse samples were collected prior to treatment with valproic acid or placebo and after 90 days of treatment. The methylation status of five tumor suppressor genes and histone acetylation were evaluated by pyrosequencing and ELISA techniques, respectively. Differences between the 90-day and baseline oral rinse acetylation and methylation results were analyzed by comparing groups. Thirty-four patients were considered for analysis. The mean percentage adherence in the valproic and placebo groups was 93.4 and 93.0, respectively (p = 0.718). There was no statistically significant difference between groups when comparing the medians of the histone acetylation ratio and the methylation ratio for most of the studied genes. A significant reduction in the DCC methylation pattern was observed in the valproic group (p = 0.023). The use of valproic acid was safe and accompanied by good therapeutic adherence. DCC methylation was lower in the valproic acid group than in the placebo group.


Assuntos
Acetilação/efeitos dos fármacos , Metilação de DNA/efeitos dos fármacos , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Ácido Valproico/uso terapêutico , Método Duplo-Cego , Feminino , Neoplasias de Cabeça e Pescoço/metabolismo , Histonas/metabolismo , Humanos , Masculino , Estudos Prospectivos , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo
11.
Curr Res Immunol ; 2: 175-183, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35492395

RESUMO

The content of tumor-derived extracellular vesicles (EVs) can regulate the tumor microenvironment and functionally acts in favor of cancer aggressiveness. To better elucidate the role of EVs in the interplay between immune system and tumor microenvironment, the purpose of this study was to analyze the effect of head and neck squamous cells carcinoma (HNSCC)-derived EVs on the modulation of inflammasomes - mediators of pyroptosis and secretion of inflammatory factors by macrophages. Our results showed that macrophages treated with the Vesicular Secretome Fraction (VSF) isolated from patient-derived HNSCC presented a reduction in the secretion of mature IL-1ß and caspase-1 without affecting cell viability. An analysis of the protein content of HNSCC-derived VSF by antibody array revealed that some of the most expressed proteins share a correlation with Transforming Growth Factor-beta (TGF-ß) activity. Since TGF-ß is related to the inhibition of the NF-kB-related pathways, including those required for the priming phase of the inflammasomes, we sought to evalute the interference of the VSF in the induction of inflammasome components. In fact, HNSCC-derived VSF inhibited the induction of pro-IL-1ß and pro-caspase-1 proteins and NLRP3 gene expression during the priming phase of inflammasome activation. Thus, our findings contribute to a better understanding of how tumor-derived EVs modulate inflammatory response by demonstrating their role in inhibiting NLRP3 inflammasomes.

13.
Histopathology ; 57(5): 689-98, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21083599

RESUMO

AIMS: Claudins, a large family of essential tight junction (TJ) proteins, are abnormally regulated in human carcinomas, especially claudin-7. The aim of this study was to investigate claudin-7 expression and alterations in oral squamous cell carcinoma (OSCC). METHODS AND RESULTS: Expression of claudin-7 was analysed in 132 cases of OSCC organized in a tissue microarray. Claudin-7 mRNA transcript was evaluated using real-time polymerase chain reaction and the methylation status of the promoter was also assessed. Claudin-7 was negative in 58.3% of the cases. Loss of claudin-7 protein expression was associated with recurrence (P = 0.019), tumour size (P = 0.014), clinical stage of OSCC (P = 0.055) and disease-free survival (P = 0.015). Down-regulation of the claudin-7 mRNA transcripts was observed in 78% of the cases, in accordance with immunoexpression. Analysis of the methylation status of the promoter region of claudin-7 revealed that treatment of O28 cells (that did not express claudin-7 mRNA transcripts) with 5-Aza-2'-Deoxycytidine (5-Aza-dC) led to the re-expression of claudin-7 mRNA transcript. CONCLUSION: Loss of claudin-7 expression is associated with important subcellular processes in OSCC with impact on clinical parameters.


Assuntos
Carcinoma de Células Escamosas/genética , Regulação para Baixo , Proteínas de Membrana/genética , Neoplasias Bucais/genética , Adulto , Idoso , Azacitidina/análogos & derivados , Azacitidina/metabolismo , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Claudinas , Decitabina , Feminino , Humanos , Imuno-Histoquímica , Masculino , Proteínas de Membrana/metabolismo , Pessoa de Meia-Idade , Neoplasias Bucais/patologia , RNA Mensageiro/metabolismo
14.
Mol Med Rep ; 19(6): 5023-5029, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31059005

RESUMO

Multiple myeloma (MM) is an incurable disease; a better understanding of the molecular aspects of this hematological malignancy could contribute to the development of new treatment strategies and help to improve the survival rates of patients with MM. Previously, the methylation status of the deleted in colorectal cancer (DCC) gene was correlated with the survival rate of patients with MM, thus the main goal of this study was to understand DCC contribution to MM tumorigenesis, and to assess the impact of DCC inhibition in the MM response to treatment with bortezomib. Our results demonstrated that hypermethylation of the DCC promoter inhibits gene expression, and DCC silencing is significantly correlated with a reduction in cell viability and an increase in cell death induced by bortezomib. In conclusion, our results suggested that hypermethylation is an important mechanism of DCC expression regulation in MM and that the absence of DCC contributes to the enhanced sensitivity to treatment with bortezomib.


Assuntos
Bortezomib/farmacologia , Receptor DCC/metabolismo , Regulação para Baixo/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Receptor DCC/antagonistas & inibidores , Receptor DCC/genética , Metilação de DNA/efeitos dos fármacos , Humanos , Mieloma Múltiplo/metabolismo , Mieloma Múltiplo/patologia , Regiões Promotoras Genéticas , Interferência de RNA , RNA Interferente Pequeno/metabolismo
15.
Head Neck ; 41(5): 1199-1205, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30803092

RESUMO

BACKGROUND: There is a paucity of plasma-based biomarkers that predict outcome in patients with head and neck squamous cell carcinoma (HNSCC) treated with chemoradiation therapy (CRT). Here, we evaluate the prognostic potential of plasma Melanoma-Antigen Recognized by T-cells 1 (MLANA) in this setting. METHODS: MLANA expression in HNSCC lines were evaluated by reverse transcription polymerase chain reaction, whereas plasma levels were quantified using ELISA in 48 patients with locally advanced HNSCC undergoing a phase 2 trial with CRT. RESULTS: MLANA is expressed at variable levels in a panel of HNSCC lines. In plasma, levels were elevated in patients with tumor relapse compared to those without (P < .004); 73.9% of the patients expressing high plasma MLANA levels progressed with recurrent disease (P = .020). Multivariate analysis showed that plasma MLANA levels and tumor resectability were independent prognostic factors for progression free survival. CONCLUSION: Plasma MLANA expression appears to be an effective noninvasive biomarker for outcomes in patients treated with CRT, and could potentially guide therapeutic decisions in this context.


Assuntos
Quimiorradioterapia , Neoplasias de Cabeça e Pescoço/sangue , Antígeno MART-1/sangue , Carcinoma de Células Escamosas de Cabeça e Pescoço/sangue , Adulto , Idoso , Biomarcadores Tumorais/sangue , Linhagem Celular Tumoral , Progressão da Doença , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Quimioterapia de Indução , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Carcinoma de Células Escamosas de Cabeça e Pescoço/terapia
16.
Mol Carcinog ; 47(10): 757-67, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18348187

RESUMO

The clear cell subtype of renal cell carcinoma (RCC) is the most lethal and prevalent cancer of the urinary system. To investigate the molecular changes associated with malignant transformation in clear cell RCC, the gene expression profiles of matched samples of tumor and adjacent non-neoplastic tissue were obtained from six patients. A custom-built cDNA microarray platform was used, comprising 2292 probes that map to exons of genes and 822 probes for noncoding RNAs mapping to intronic regions. Intronic transcription was detected in all normal and neoplastic renal tissues. A subset of 55 transcripts was significantly down-regulated in clear cell RCC relative to the matched nontumor tissue as determined by a combination of two statistical tests and leave-one-out patient cross-validation. Among the down-regulated transcripts, 49 mapped to untranslated or coding exons and 6 were intronic relative to known exons of protein-coding genes. Lower levels of expression of SIN3B, TRIP3, SYNJ2BP and NDE1 (P < 0.02), and of intronic transcripts derived from SND1 and ACTN4 loci (P < 0.05), were confirmed in clear cell RCC by Real-time RT-PCR. A subset of 25 transcripts was deregulated in additional six nonclear cell RCC samples, pointing to common transcriptional alterations in RCC irrespective of the histological subtype or differentiation state of the tumor. Our results indicate a novel set of tumor suppressor gene candidates, including noncoding intronic RNAs, which may play a significant role in malignant transformations of normal renal cells.


Assuntos
Regulação para Baixo , Íntrons , Neoplasias Renais/genética , RNA não Traduzido/genética , Etiquetas de Sequências Expressas , Perfilação da Expressão Gênica , Humanos , Neoplasias Renais/patologia , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
17.
J Mol Neurosci ; 66(3): 383-389, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30284228

RESUMO

Glioblastoma (GBM) is an incurable disease ranked among the deadliest solid cancers worldwide. A better understanding on the molecular aspects of this malignancy could contribute to the development of new treatment strategies and help to improve survival rates. Previously, our group had shown that GBM patients expressing the cancer/testis antigen Opa Interacting Protein 5 (OIP5) present a longer survival period than the OIP5-negative group. The main goal of this study was to evaluate the OIP5 contribution to GBM tumorigenesis and assess the role of OIP5 in GBM cell response to lomustine, an alkylating agent used in the treatment of this malignancy. So, the effect of OIP5 knockdown was evaluated in A172 and T98G GBM cell lines. Our results demonstrated that downregulation of the OIP5 stimulates glioma cell viability and inhibits cell death-induced necrosis prompted by lomustine. In conclusion, our data shows that OIP5 expression in GBM cells seems to be able to enhance lomustine cytotoxic effects, reinforcing that this gene is a potential therapeutic target and putative molecular biomarker for treatment response in GBM.


Assuntos
Neoplasias Encefálicas/metabolismo , Proteínas Cromossômicas não Histona/genética , Resistencia a Medicamentos Antineoplásicos/genética , Glioblastoma/metabolismo , Antineoplásicos Alquilantes/farmacologia , Neoplasias Encefálicas/genética , Proteínas de Ciclo Celular , Linhagem Celular Tumoral , Proteínas Cromossômicas não Histona/metabolismo , Humanos , Lomustina/farmacologia
18.
Cancer Lett ; 245(1-2): 96-102, 2007 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-16494995

RESUMO

A TP53 germline mutation, R337H, has been previously described in children from southern Brazil with adrenocortical tumours but no documented familial history of other cancers. Here, we have screened for TP53 mutation 45 Brazilian unrelated individuals with family histories fulfilling the clinical definitions of Li-Fraumeni (LFS) or Li-Fraumeni-like (LFL) syndromes. Mutations were found in 13 patients (28.9%), including six (46.1%) R337H mutations, and four novel germline mutations (V173M, V197M, G244D and IVS6+1G>T). Families with the R337H mutation presented a wide spectrum of tumours, including breast cancers (30.4%), brain cancers (10.7%), soft tissue sarcomas (10.7%) and adrenocortical carcinomas (8.9%). Testing of 53 Brazilian subjects with no cancer history showed that R337H was not a common polymorphism in that population. Moreover, loss of heterozygocity with retention of the R337H allele was observed in a breast adenocarcinoma, supporting a role for this mutation in breast tumorigenesis. These results show that the TP53 R337H germline mutation predisposes to a larger spectrum of tumours, similar to the one reported for other TP53 mutations.


Assuntos
Mutação em Linhagem Germinativa , Síndrome de Li-Fraumeni/genética , Proteína Supressora de Tumor p53/genética , Sequência de Bases , Brasil , Análise Mutacional de DNA , Feminino , Predisposição Genética para Doença/genética , Humanos , Síndrome de Li-Fraumeni/patologia , Masculino , Mutação de Sentido Incorreto , Síndromes Neoplásicas Hereditárias/genética , Síndromes Neoplásicas Hereditárias/patologia
19.
Cancer Discov ; 7(10): 1116-1135, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28667006

RESUMO

Cholangiocarcinoma (CCA) is a hepatobiliary malignancy exhibiting high incidence in countries with endemic liver-fluke infection. We analyzed 489 CCAs from 10 countries, combining whole-genome (71 cases), targeted/exome, copy-number, gene expression, and DNA methylation information. Integrative clustering defined 4 CCA clusters-fluke-positive CCAs (clusters 1/2) are enriched in ERBB2 amplifications and TP53 mutations; conversely, fluke-negative CCAs (clusters 3/4) exhibit high copy-number alterations and PD-1/PD-L2 expression, or epigenetic mutations (IDH1/2, BAP1) and FGFR/PRKA-related gene rearrangements. Whole-genome analysis highlighted FGFR2 3' untranslated region deletion as a mechanism of FGFR2 upregulation. Integration of noncoding promoter mutations with protein-DNA binding profiles demonstrates pervasive modulation of H3K27me3-associated sites in CCA. Clusters 1 and 4 exhibit distinct DNA hypermethylation patterns targeting either CpG islands or shores-mutation signature and subclonality analysis suggests that these reflect different mutational pathways. Our results exemplify how genetics, epigenetics, and environmental carcinogens can interplay across different geographies to generate distinct molecular subtypes of cancer.Significance: Integrated whole-genome and epigenomic analysis of CCA on an international scale identifies new CCA driver genes, noncoding promoter mutations, and structural variants. CCA molecular landscapes differ radically by etiology, underscoring how distinct cancer subtypes in the same organ may arise through different extrinsic and intrinsic carcinogenic processes. Cancer Discov; 7(10); 1116-35. ©2017 AACR.This article is highlighted in the In This Issue feature, p. 1047.


Assuntos
Neoplasias dos Ductos Biliares/genética , Colangiocarcinoma/genética , Epigenômica/métodos , Estudo de Associação Genômica Ampla/métodos , Ilhas de CpG , Metilação de DNA , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Humanos , Receptor ErbB-2/genética , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/genética , Proteína Supressora de Tumor p53/genética
20.
Mol Cancer Ther ; 14(3): 828-34, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25564441

RESUMO

Despite significant advances in the treatment of head and neck squamous cell carcinoma (HNSCC), the survival rate has not changed in the last decades. Therefore, the development of novel therapeutic strategies is pursued. Cancer-testis antigens (CTA) are strong immunogenic proteins with a tumor-restricted expression pattern, and are considered ideal targets for tumor-specific immunotherapeutic approaches. In this study, using an in silico approach, we selected, among 139 previously described CTA, candidates to be evaluated in 89 HNSCC and 20 normal mucosa samples. SPANX-CD (71.9%), MAGEB2 (44.9%), MAGEA1 (44.9%), MAGEB6 (32.6%), and CXORF48 (27.0%) were found frequently expressed in HNSCC, and over 85% of the tumors expressed at least one of these five CTAs. The mRNA positivity of CXORF48, MAGEB6, and CRISP2 presented significant associations with recognized clinical features for poor outcome. Furthermore, MAGEA3/6 positivity was associated with significantly better disease-free survival (DFS, P = 0.014), and the expression of this antigen was shown to be an independent prognostic factor for tumor recurrence. In conclusion, one of five selected CTAs is expressed in at least 85% of the HNSCCs, suggesting a possible usage as target for immunotherapeutic approaches, and the mRNA-positivity for MAGEA3/6 is shown to be an independent marker for DFS.


Assuntos
Antígenos de Neoplasias/genética , Biomarcadores Tumorais/genética , Carcinoma de Células Escamosas/genética , Neoplasias de Cabeça e Pescoço/genética , Proteínas de Neoplasias/genética , Recidiva Local de Neoplasia/diagnóstico , Recidiva Local de Neoplasia/genética , Testículo/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/metabolismo , Estudos de Casos e Controles , Intervalo Livre de Doença , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Neoplasias de Cabeça e Pescoço/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Mucosa/metabolismo , RNA Mensageiro/genética , Estudos Retrospectivos , Carcinoma de Células Escamosas de Cabeça e Pescoço
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