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1.
Proc Natl Acad Sci U S A ; 119(33): e2203203119, 2022 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-35947614

RESUMO

Human cells encode up to 15 DNA polymerases with specialized functions in chromosomal DNA synthesis and damage repair. In contrast, complex DNA viruses, such as those of the herpesviridae family, encode a single B-family DNA polymerase. This disparity raises the possibility that DNA viruses may rely on host polymerases for synthesis through complex DNA geometries. We tested the importance of error-prone Y-family polymerases involved in translesion synthesis (TLS) to human cytomegalovirus (HCMV) infection. We find most Y-family polymerases involved in the nucleotide insertion and bypass of lesions restrict HCMV genome synthesis and replication. In contrast, other TLS polymerases, such as the polymerase ζ complex, which extends past lesions, was required for optimal genome synthesis and replication. Depletion of either the polζ complex or the suite of insertion polymerases demonstrate that TLS polymerases suppress the frequency of viral genome rearrangements, particularly at GC-rich sites and repeat sequences. Moreover, while distinct from HCMV, replication of the related herpes simplex virus type 1 is impacted by host TLS polymerases, suggesting a broader requirement for host polymerases for DNA virus replication. These findings reveal an unexpected role for host DNA polymerases in ensuring viral genome stability.


Assuntos
Dano ao DNA , Replicação do DNA , Vírus de DNA , DNA Polimerase Dirigida por DNA , Genoma Viral , Citomegalovirus/genética , Citomegalovirus/fisiologia , Reparo do DNA , Vírus de DNA/genética , Vírus de DNA/fisiologia , DNA Polimerase Dirigida por DNA/metabolismo , Humanos , Replicação Viral
2.
Br J Cancer ; 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38969867

RESUMO

BACKGROUND: Resistance to chemotherapy is a major problem in the treatment of patients with triple-negative breast cancer (TNBC). Preclinical data suggest that TNBC is dependent on proteasomes; however, clinical observations indicate that the efficacy of proteasome inhibitors in TNBC may be limited, suggesting the need for combination therapies. METHODS: We compared bortezomib and carfilzomib and their combinations with nelfinavir and lopinavir in TNBC cell lines and primary cells with regard to their cytotoxic activity, functional proteasome inhibition, and induction of the unfolded protein response (UPR). Furthermore, we evaluated the involvement of sXBP1, ABCB1, and ABCG2 in the cytotoxic activity of drug combinations. RESULTS: Carfilzomib, via proteasome ß5 + ß2 inhibition, is more cytotoxic in TNBC than bortezomib, which inhibits ß5 + ß1 proteasome subunits. The cytotoxicity of carfilzomib was significantly potentiated by nelfinavir or lopinavir. Carfilzomib with lopinavir induced endoplasmic reticulum stress and pro-apoptotic UPR through the accumulation of excess proteasomal substrate protein in TNBC in vitro. Moreover, lopinavir increased the intracellular availability of carfilzomib by inhibiting carfilzomib export from cells that express high levels and activity of ABCB1, but not ABCG2. CONCLUSION: Proteasome inhibition by carfilzomib combined with nelfinavir/lopinavir represents a potential treatment option for TNBC, warranting further investigation.

3.
Neoplasma ; 70(2): 179-187, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36812229

RESUMO

miRNA expression in triple-negative breast cancers (TNBC) has mainly been studied from a methodological viewpoint. However, it has not been considered that miRNA expression profile may be associated with a specific morphological entity inside every tumor. The verification of this hypothesis on a set of 25 TNBCs was the subject of our previous work, where we confirmed specific expression of the studied miRNAs in 82 samples of different morphologies including inflammatory infiltrate, spindle cell, clear cell, and metastases after RNA extraction and purification as well as microchip and biostatistical analysis. In the current work, we demonstrate a low suitability of in situ hybridization method for miRNA detection compared to RT-qPCR, and in detail discuss the biological role of 8 miRNAs with the most significant changes of expression.


Assuntos
MicroRNAs , Neoplasias de Mama Triplo Negativas , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia
4.
Eur J Public Health ; 32(6): 852-857, 2022 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-36374643

RESUMO

BACKGROUND: As a system of European Reference Networks (ERNs) emerges, the differences in quality of care for patients with rare cancers may increase at national level. We aimed to elucidate the processes and healthcare planning principles through which the reference centres (RCs) for rare cancers are embedded in national health systems. METHODS: We used a multiple case-study design based on the experiences of Czechia, Finland, France, Italy, Lithuania and Spain. Using sarcoma as an example of rare cancer, 52 semi-structured interviews were conducted during on-site visits, including a multidisciplinary group of professionals, Ministry of Health professionals, patient representatives and European policymakers. RESULTS: The comparative analysis showed substantial heterogeneity in the processes for formalizing RCs' status and in their levels of integration in the different health systems, but two models (centre-based and the network-based) can be envisaged at national level. RCs for rare cancers were legally established only in France and Spain. Expert clinicians cooperate in a structured way, using network mechanisms, in France and Italy, and these countries, plus Finland and Lithuania, had a referral system to facilitate patients' access from non-expert centres to RCs. Seven key healthcare planning principles in instituting RCs at the national level were identified. CONCLUSIONS: The conditions governing patient access to treatment centres-whether RCs or not-are decided at the national level. It is advisable to progressively align the European and national levels so that the RCs that participate in the ERNs also play a significant role at the national level.


Assuntos
Neoplasias , Humanos , Espanha , Itália , Encaminhamento e Consulta , França
5.
J Med Internet Res ; 22(11): e20709, 2020 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-33196452

RESUMO

BACKGROUND: eHealth mindfulness-based programs (eMBPs) are on the rise in complex oncology and palliative care. However, we are still at the beginning of answering the questions of how effective eMBPs are and for whom, and what kinds of delivery modes are the most efficient. OBJECTIVE: This systematic review aims to examine the feasibility and efficacy of eMBPs in improving the mental health and well-being of patients with cancer, to describe intervention characteristics and delivery modes of these programs, and to summarize the results of the included studies in terms of moderators, mediators, and predictors of efficacy, adherence, and attrition. METHODS: In total, 4 databases (PubMed, PsycINFO, Scopus, and Web of Knowledge) were searched using relevant search terms (eg, mindfulness, program, eHealth, neoplasm) and their variations. No restrictions were imposed on language or publication type. The results of the efficacy of eMBPs were synthesized through the summarizing effect estimates method. RESULTS: A total of 29 published papers describing 24 original studies were included in this review. In general, the results indicate that eMBPs have the potential to reduce the levels of stress, anxiety, depression, fatigue, sleep problems, and pain, and improve the levels of mindfulness, posttraumatic growth, and some parameters of general health. The largest median of Cohen d effect sizes were observed in reducing anxiety and depression (within-subject: median -0.38, IQR -0.62 to -0.27; between-group: median -0.42, IQR -0.58 to -0.22) and facilitating posttraumatic growth (within-subject: median 0.42, IQR 0.35 to 0.48; between-group: median 0.32, IQR 0.22 to 0.39). The efficacy of eMBP may be comparable with that of parallel, face-to-face MBPs in some cases. All studies that evaluated the feasibility of eMBPs reported that they are feasible for patients with cancer. Potential moderators, mediators, and predictors of the efficacy, attrition, and adherence of eMBPs are discussed. CONCLUSIONS: Although the effects of the reviewed studies were highly heterogeneous, the review provides evidence that eMBPs are an appropriate way for mindfulness practice to be delivered to patients with cancer. Thus far, existing eMBPs have mostly attempted to convert proven face-to-face mindfulness programs to the eHealth mode. They have not yet fully exploited the potential of eHealth technology.


Assuntos
Atenção Plena/métodos , Neoplasias/psicologia , Telemedicina/métodos , Estudos de Avaliação como Assunto , Humanos
6.
Int J Mol Sci ; 20(18)2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31510013

RESUMO

MicroRNAs (miRNAs) are small non-coding RNAs that post-transcriptionally regulate gene expression. Each step of their production and maturation has to be strictly regulated, as any disruption of control mechanisms may lead to cancer. Thus, we have measured the expression of 19 genes involved in miRNAs biogenesis pathway in tumor tissues of 239 colorectal cancer (CRC) patients, 17 CRC patients with liver metastases and 239 adjacent tissues using real-time PCR. Subsequently, the expression of analyzed genes was correlated with the clinical-pathological features as well as with the survival of patients. In total, significant over-expression of all analyzed genes was observed in tumor tissues as well as in liver metastases except for LIN28A/B. Furthermore, it was shown that the deregulated levels of some of the analyzed genes significantly correlate with tumor stage, grade, location, size and lymph node positivity. Finally, high levels of DROSHA and TARBP2 were associated with shorter disease-free survival, while the over-expression of XPO5, TNRC6A and DDX17 was detected in tissues of patients with shorter overall survival and poor prognosis. Our data indicate that changed levels of miRNA biogenesis genes may contribute to origin as well as progression of CRC; thus, these molecules could serve as potential therapeutic targets.


Assuntos
Vias Biossintéticas/genética , Neoplasias Colorretais/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas/genética , MicroRNAs/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Colorretais/patologia , Feminino , Humanos , Estimativa de Kaplan-Meier , Carioferinas/genética , Neoplasias Hepáticas/secundário , Masculino , Pessoa de Meia-Idade , Prognóstico , Ribonuclease III/genética
7.
J Cell Mol Med ; 22(3): 2033-2038, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29363887

RESUMO

Urinary microRNAs (miRNAs) are emerging as clinically useful tool for early and non-invasive detection of various types of cancer including bladder cancer (BCA). In this study, 205 patients with BCA and 99 healthy controls were prospectively enrolled. Expression profiles of urinary miRNAs were obtained using Affymetrix miRNA microarrays (2578 miRNAs) and candidate miRNAs further validated in independent cohorts using qRT-PCR. Whole-genome profiling identified 76 miRNAs with significantly different concentrations in urine of BCA compared to controls (P < 0.01). In the training and independent validation phase of the study, miR-31-5p, miR-93-5p and miR-191-5p were confirmed to have significantly higher levels in urine of patients with BCA in comparison with controls (P < 0.01). We further established 2-miRNA-based urinary DxScore (miR-93-5p, miR-31-5p) enabling sensitive BCA detection with AUC being 0.84 and 0.81 in the training and validation phase, respectively. Moreover, DxScore significantly differed in the various histopathological subgroups of BCA and decreased post-operatively. In conclusion, we identified and independently validated cell-free urinary miRNAs as promising biomarkers enabling non-invasive detection of BCA.


Assuntos
Biomarcadores Tumorais/genética , Carcinoma/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Neoplasias da Bexiga Urinária/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/urina , Carcinoma/diagnóstico , Carcinoma/patologia , Carcinoma/urina , Estudos de Casos e Controles , Feminino , Genoma Humano , Estudo de Associação Genômica Ampla , Humanos , Masculino , MicroRNAs/urina , Pessoa de Meia-Idade , Gradação de Tumores , Estudos Prospectivos , Neoplasias da Bexiga Urinária/diagnóstico , Neoplasias da Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/urina
8.
Br J Cancer ; 118(6): 813-819, 2018 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-29462126

RESUMO

Background:The intratumoural heterogeneity, often driven by epithelial-to-mesenchymal transition (EMT), significantly contributes to chemoresistance and disease progression in adenocarcinomas. Methods:We introduced a high-throughput screening platform to identify surface antigens that associate with epithelial­mesenchymal plasticity in well-defined pairs of epithelial cell lines and their mesenchymal counterparts. Using multicolour flow cytometry, we then analysed the expression of 10 most robustly changed antigens and identified a 10-molecule surface signature, in pan-cytokeratin-positive/EpCAM-positive and -negative fractions of dissociated breast tumours. Results:We found that surface CD9, CD29, CD49c, and integrin ß5 are lost in breast cancer cells that underwent EMT in vivo. The tetraspanin family member CD9 was concordantly downregulated both in vitro and in vivo and associated with epithelial phenotype and favourable prognosis. Conclusions:We propose that overall landscape of 10-molecule surface signature expression reflects the epithelial­mesenchymal plasticity in breast cancer.


Assuntos
Antígenos de Neoplasias/biossíntese , Antígenos de Superfície/biossíntese , Neoplasias da Mama/genética , Neoplasias da Mama/imunologia , Antígenos de Neoplasias/imunologia , Antígenos de Superfície/imunologia , Biomarcadores Tumorais , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Plasticidade Celular/imunologia , Reprogramação Celular/fisiologia , Transição Epitelial-Mesenquimal/imunologia , Feminino , Citometria de Fluxo , Ensaios de Triagem em Larga Escala , Humanos , Metástase Neoplásica , Tetraspanina 29/biossíntese , Tetraspanina 29/imunologia , Transcrição Gênica
9.
Breast Cancer Res Treat ; 163(3): 475-484, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28349272

RESUMO

PURPOSE: The basal-A subtype of triple-negative breast cancer is characterized by high levels of ΔNp63. Various functions have been proposed for p63 in breast cancer initiation and growth, and p63 mediates chemotherapeutic response in a subset of triple-negative breast cancers. We investigated the signaling pathways that are controlled by ΔNp63 in basal-A triple-negative breast cancer. METHODS: Human basal-A triple-negative breast cancer cell lines with ΔNp63α induction or inhibition were studied, along with primary human triple-negative breast cancer tissues. Proteomic, phospho-kinase array, mRNA measurements, and immunohistochemistry were employed. RESULTS: Global phosphoproteomics identified increased EGFR phosphorylation in MDA-MB-468 cells expressing ΔNp63α. ΔNp63α expression increased EGFR mRNA, total EGFR protein, and phospho-EGFR(Y1086), whereas silencing endogenous ΔNp63 in HCC1806 cells reduced both total and phospho-EGFR levels and inhibited the ability of EGF to activate EGFR. EGFR pathway gene expression analysis indicated that ΔNp63 alters EGFR-regulated genes involved in cell adhesion, migration, and angiogenesis. Addition of EGF or neutralizing EGFR antibodies demonstrated that EGFR activation is responsible for ΔNp63-mediated loss of cellular adhesion. Finally, immunohistochemical staining showed that p63-positive triple-negative breast cancers were more likely to express high levels of EGFR than p63-negative cancers, corroborated by in silico analysis of gene expression profiling data. CONCLUSIONS: These data identify EGFR as a major target for ΔNp63 regulation that influences cancer cell adhesion in basal-like triple-negative breast cancer.


Assuntos
Fator de Crescimento Epidérmico/genética , Receptores ErbB/genética , Proteínas de Membrana/genética , Neoplasias de Mama Triplo Negativas/genética , Adesão Celular/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Fator de Crescimento Epidérmico/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Invasividade Neoplásica/genética , Metástase Neoplásica , Proteômica , Transdução de Sinais , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/patologia
10.
Tumour Biol ; 39(10): 1010428317727479, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29025359

RESUMO

A broad spectrum of tumors develop resistance to classic chemotherapy, necessitating the discovery of new therapies. One successful strategy exploits the synthetic lethality between poly(ADP-ribose) polymerase 1/2 proteins and DNA damage response genes, including BRCA1, a factor involved in homologous recombination-mediated DNA repair, and CDK12, a transcriptional kinase known to regulate the expression of DDR genes. CHK1 inhibitors have been shown to enhance the anti-cancer effect of DNA-damaging compounds. Since loss of BRCA1 increases replication stress and leads to DNA damage, we tested a hypothesis that CDK12- or BRCA1-depleted cells rely extensively on S-phase-related CHK1 functions for survival. The silencing of BRCA1 or CDK12 sensitized tumor cells to CHK1 inhibitors in vitro and in vivo. BRCA1 downregulation combined with CHK1 inhibition induced excessive amounts of DNA damage, resulting in an inability to complete the S-phase. Therefore, we suggest CHK1 inhibition as a strategy for targeting BRCA1- or CDK12-deficient tumors.


Assuntos
Proteína BRCA1/genética , Quinase 1 do Ponto de Checagem/genética , Neoplasias Colorretais/genética , Quinases Ciclina-Dependentes/genética , Animais , Proteína BRCA1/antagonistas & inibidores , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Quinases Ciclina-Dependentes/antagonistas & inibidores , Dano ao DNA/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Inativação Gênica , Células HCT116 , Humanos , Camundongos , Poli(ADP-Ribose) Polimerase-1/genética , Pirazóis/administração & dosagem , Pirimidinas/administração & dosagem , Ensaios Antitumorais Modelo de Xenoenxerto
11.
BMC Cancer ; 17(1): 880, 2017 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-29268716

RESUMO

BACKGROUND: It is well known that patient characteristics and survival outcomes in randomized trials may not necessarily be similar to those in real-life clinical practice. The aim of the present study was to analyse second line treatment strategies in the real-world practice and to estimate the outcomes of patients treated with second-line targeted therapy for metastatic renal cell carcinoma (mRCC). METHODS: This is a retrospective, registry-based study using data from the national registry of targeted therapies for mRCC. The RENIS registry contains data on 3049 patients who started the therapy with at least one targeted agent before 31 December, 2014. Of these patients, 1029 had a record of at least two different targeted therapies and sufficient data for analysis. Survival analysis was carried out using the Kaplan-Meier method. Statistical significance of differences in survival between subgroups was assessed using the log-rank test. RESULTS: The median overall survival from the start of second-line treatment was 17.0 months (95% confidence interval [CI] 14.5-19.5 months), 17.1 months (95% CI 14.5-19.8), and 15.4 months (95% CI 11.0-19.7) for second-line everolimus, sorafenib, and sunitinib, respectively. Patients receiving second-line everolimus were older at the start of second-line treatment, more likely to have metachronous disease, and less likely to be previously treated with cytokines or to continue to third-line treatment than patients treated with second-line sunitinib or sorafenib. Progression-free survival (PFS) correlated with PFS on first-line treatment only for everolimus. CONCLUSIONS: In this retrospective study, no significant differences in survival were observed between the cohorts treated with different second-line agents including everolimus, sorafenib, and sunitinib.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Papilar/secundário , Carcinoma de Células Renais/patologia , Neoplasias Renais/secundário , Terapia de Alvo Molecular , Sistema de Registros/estatística & dados numéricos , Terapia de Salvação , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Papilar/tratamento farmacológico , Carcinoma de Células Renais/tratamento farmacológico , Feminino , Seguimentos , Humanos , Neoplasias Renais/tratamento farmacológico , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida
12.
Carcinogenesis ; 37(10): 941-950, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27485599

RESUMO

Early detection of colorectal cancer is the main prerequisite for successful treatment and reduction of mortality. Circulating microRNAs were previously identified as promising diagnostic, prognostic and predictive biomarkers. The purpose of this study was to identify serum microRNAs enabling early diagnosis and prognosis prediction of colon cancer. In total, serum samples from 427 colon cancer patients and 276 healthy donors were included in three-phase biomarker study. Large-scale microRNA expression profiling was performed using Illumina small RNA sequencing. Diagnostic and prognostic potential of identified microRNAs was validated on independent training and validation sets of samples using RT-qPCR. Fifty-four microRNAs were found to be significantly deregulated in serum of colon cancer patients compared to healthy donors (P < 0.01). A diagnostic four-microRNA signature consisting of miR-23a-3p, miR-27a-3p, miR-142-5p and miR-376c-3p was established (AUC = 0.917), distinguishing colon cancer patients from healthy donors with sensitivity of 89% and specificity of 81% (AUC = 0.922). This panel of microRNAs exhibited high diagnostic performance also when analyzed separately in colon cancer patients in early stages of the disease (T1-4N0M0; AUC = 0.877). Further, a prognostic panel based on the expression of miR-23a-3p and miR-376c-3p independent of TNM stage was established (HR 2.30; 95% CI 1.44-3.66; P < 0.0004). In summary, highly sensitive signatures of circulating microRNAs enabling non-invasive early detection and prognosis prediction of colon cancer were identified.


Assuntos
Biomarcadores Tumorais/sangue , Neoplasias do Colo/sangue , MicroRNAs/sangue , Idoso , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Detecção Precoce de Câncer , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico
13.
Tumour Biol ; 37(11): 14653-14658, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27619681

RESUMO

MicroRNAs (miRNAs) have been proven to be important oncogenes and tumor suppressors in wide range of cancers, including renal cell carcinoma (RCC). In our study, we evaluated miRNA-429 as potential diagnostic/prognostic biomarker in 172 clear cell RCC patients and as a potential regulator of epithelial-mesenchymal transition (EMT) in vitro. We demonstrated that miR-429 is down-regulated in tumor tissue samples (P < 0.0001) and is significantly associated with cancer metastasis (P < 0.0001), shorter disease-free (P = 0.0105), and overall survival (P = 0.0020). In addition, ectopic expression of miR-429 in 786-0 RCC cells followed by TGF-ß treatment led to increase in the levels of E-cadherin expression (P < 0.0001) and suppression of cellular migration (P < 0.0001) in comparison to TGF-ß-treated controls. Taken together, our findings suggest that miR-429 may serve as promising diagnostic and prognostic biomarker in RCC patients. We further suggest that miR-429 has a capacity to inhibit loss of E-cadherin in RCC cells undergoing EMT and consequently attenuate their motility.


Assuntos
Carcinoma de Células Renais/secundário , Movimento Celular , Transição Epitelial-Mesenquimal , Regulação Neoplásica da Expressão Gênica , Neoplasias Renais/patologia , MicroRNAs/genética , Recidiva Local de Neoplasia/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos CD , Biomarcadores Tumorais , Caderinas/genética , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/terapia , Estudos de Casos e Controles , Proliferação de Células , Terapia Combinada , Regulação para Baixo , Feminino , Seguimentos , Humanos , Neoplasias Renais/genética , Neoplasias Renais/terapia , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Invasividade Neoplásica , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/terapia , Estadiamento de Neoplasias , Prognóstico , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Taxa de Sobrevida , Fator de Crescimento Transformador beta/genética , Células Tumorais Cultivadas
14.
Tumour Biol ; 37(10): 13385-13390, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27460088

RESUMO

Long non-coding RNA TUG1 is involved in the development and progression of a variety of tumors. Little is known about TUG1 function in high-grade muscle-invasive bladder cancer (MIBC). The aims of our study were to determine expression levels of long non-coding RNA TUG1 in tumor tissue, to evaluate its relationship with clinico-pathological features of high-grade MIBC, and to describe its function in MIBC cells in vitro. TUG1 expression levels were determined in paired tumor and adjacent non-tumor bladder tissues of 47 patients with high-grade MIBC using real-time PCR. Cell line T-24 and siRNA silencing were used to study the TUG1 function in vitro. We observed significantly increased levels of TUG1 in tumor tissue in comparison to adjacent non-tumor bladder tissue (P < 0.0001). TUG1 levels were significantly increased in metastatic tumors (P = 0.0147) and were associated with shorter overall survival of MIBC patients (P = 0.0241). TUG1 silencing in vitro led to 34 % decrease in cancer cell proliferation (P = 0.0004) and 23 % reduction in migration capacity of cancer cells (P < 0.0001). We did not observe any significant effects of TUG1 silencing on cell cycle distribution and number of apoptotic cells. Our study confirmed overexpression of TUG1 in MIBC tumor tissue and described its association with worse overall survival in high-grade MIBC patients. Together with in vitro observations, these data suggest an oncogenic role of TUG1 and its potential usage as biomarker or therapeutic target in MIBC.


Assuntos
Biomarcadores Tumorais/genética , Movimento Celular , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Neoplasias Musculares/patologia , RNA Longo não Codificante/genética , Neoplasias da Bexiga Urinária/patologia , Apoptose , Ciclo Celular , Progressão da Doença , Feminino , Humanos , Neoplasias Musculares/genética , Invasividade Neoplásica , Estadiamento de Neoplasias , Prognóstico , RNA Longo não Codificante/antagonistas & inibidores , RNA Mensageiro/genética , RNA Interferente Pequeno/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas , Neoplasias da Bexiga Urinária/genética
15.
Tumour Biol ; 37(6): 7719-27, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26692101

RESUMO

Glioblastoma multiforme (GBM) is the most aggressive form of brain tumor. Despite radical surgery and radiotherapy supported by chemotherapy, the disease still remains incurable with an extremely low median survival rate of 12-15 months from the time of initial diagnosis. The main cause of treatment failure is considered to be the presence of cells that are resistant to the treatment. MicroRNAs (miRNAs) as regulators of gene expression are involved in the tumor pathogenesis, including GBM. MiR-338 is a brain-specific miRNA which has been described to target pathways involved in proliferation and differentiation. In our study, miR-338-3p and miR-338-5p were differentially expressed in GBM tissue in comparison to non-tumor brain tissue. Overexpression of miR-338-3p with miRNA mimic did not show any changes in proliferation rates in GBM cell lines (A172, T98G, U87MG). On the other hand, pre-miR-338-5p notably decreased proliferation and caused cell cycle arrest. Since radiation is currently the main treatment modality in GBM, we combined overexpression of pre-miR-338-5p with radiation, which led to significantly decreased cell proliferation, increased cell cycle arrest, and apoptosis in comparison to irradiation-only cells. To better elucidate the mechanism of action, we performed gene expression profiling analysis that revealed targets of miR-338-5p being Ndfip1, Rheb, and ppp2R5a. These genes have been described to be involved in DNA damage response, proliferation, and cell cycle regulation. To our knowledge, this is the first study to describe the role of miR-338-5p in GBM and its potential to improve the sensitivity of GBM to radiation.


Assuntos
Neoplasias Encefálicas/patologia , Dano ao DNA/genética , Regulação Neoplásica da Expressão Gênica/genética , Glioblastoma/patologia , MicroRNAs/genética , Proteínas de Neoplasias/biossíntese , RNA Neoplásico/genética , Tolerância a Radiação/genética , Neoplasias Encefálicas/genética , Proteínas de Transporte/biossíntese , Proteínas de Transporte/genética , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos da radiação , Divisão Celular/efeitos dos fármacos , Divisão Celular/efeitos da radiação , Linhagem Celular Tumoral , Feminino , Perfilação da Expressão Gênica , Glioblastoma/genética , Humanos , Masculino , Proteínas de Membrana/biossíntese , Proteínas de Membrana/genética , Pessoa de Meia-Idade , Proteínas Monoméricas de Ligação ao GTP/biossíntese , Proteínas Monoméricas de Ligação ao GTP/genética , Proteínas de Neoplasias/genética , Neuropeptídeos/biossíntese , Neuropeptídeos/genética , Proteína Fosfatase 2/biossíntese , Proteína Fosfatase 2/genética , Proteína Enriquecida em Homólogo de Ras do Encéfalo
16.
Tumour Biol ; 37(6): 8007-18, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26711784

RESUMO

Esophageal cancer is a malignant disease with poor prognosis, increasing incidence, and ineffective treatment options. MicroRNAs are post-transcriptional regulators of gene expression involved in many biological processes including carcinogenesis. We determined miR-205 expression levels in tumor/non-tumor tissues of 45 esophageal cancer patients using qPCR and found that decreased level of miR-205 in tumor tissue correlates with poor overall survival in esophageal adenocarcinoma patients. Further, we observed significantly higher levels of miR-205 in tumor tissue of esophageal squamous cell carcinoma. Ectopic overexpression of miR-205 in adenocarcinoma cell line SK-GT-4 led to decreased cell proliferation, cell cycle arrest in G1, and decreased migration ability. Conversely, in squamous cell line KYSE-150, same effects like inhibition of proliferation, migration, and colony-forming potential and cell cycle arrest in G2 were observed after silencing of miR-205. We performed global gene expression profiling and revealed that suppressive functioning of miR-205 in adenocarcinoma could be realized through regulation of epithelial-mesenchymal transition (EMT), whereas oncogenic in squamous cell carcinoma by regulation of metalloproteinase 10. Our results suggest that miR-205 could serve as biomarker in esophageal cancer and acts as a tumor suppressor in esophageal adenocarcinoma and oncogene in esophageal squamous cell carcinoma.


Assuntos
Adenocarcinoma/patologia , Carcinoma de Células Escamosas/patologia , Neoplasias Esofágicas/patologia , MicroRNAs/fisiologia , Oncogenes/genética , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Adulto , Idoso , Apoptose/genética , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Ciclo Celular/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Transição Epitelial-Mesenquimal/genética , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/metabolismo , Carcinoma de Células Escamosas do Esôfago , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica/fisiologia , Genes Supressores de Tumor , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase em Tempo Real , Taxa de Sobrevida
17.
Carcinogenesis ; 36(5): 521-7, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25784377

RESUMO

Esophageal adenocarcinoma (EAC) is highly aggressive malignancy that frequently develops from Barrett's esophagus (BE), a premalignant pathologic change occurring in the lower end of the esophagus. MicroRNAs (miRNAs) are small, non-coding RNAs that function as posttranscriptional regulators of gene expression and were repeatedly proved to play key roles in pathogenesis of BE as well as EAC. In our study, we used Affymetrix GeneChip miRNA arrays to obtain miRNA expression profiles in total of 119 tissue samples [24 normal esophageal mucosa (EM), 60 BE and 35 EAC]. We identified a number of miRNAs, that showed altered expression progressively in sequence EM, BE and EAC, including for instance miR-21, miR-25, miR-194 and miR-196a with increasing levels (P < 0.0015) and miR-203, miR-205, miR-210 and miR-378 with decreasing levels (P < 0.0001). The subsequent analysis revealed four diagnostic miRNA signatures enabling to distinguish EM and BE [12 miRNAs, area under curve (AUC) = 0.971], EM and EAC (13 miRNAs, AUC = 1.0), BE without and BE with dysplasia (21 miRNAs, AUC = 0.856) and BE without dysplastic changes and BE with dysplasia together with EAC (2 miRNAs, AUC = 0.886). We suggest that miRNA expression profiling expands current knowledge in molecular pathology of Barrett's-based carcinogenesis and enables identification of molecular biomarkers for early detection of BE dysplasia and progression to EAC.


Assuntos
Adenocarcinoma/genética , Esôfago de Barrett/genética , Biomarcadores Tumorais/genética , Neoplasias Esofágicas/genética , Esôfago/metabolismo , Perfilação da Expressão Gênica , MicroRNAs/genética , Adenocarcinoma/patologia , Idoso , Esôfago de Barrett/patologia , Estudos de Casos e Controles , Progressão da Doença , Neoplasias Esofágicas/patologia , Esôfago/patologia , Feminino , Seguimentos , Regulação Neoplásica da Expressão Gênica , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Análise de Sequência com Séries de Oligonucleotídeos , Prognóstico , Curva ROC , Estudos Retrospectivos
18.
Tumour Biol ; 36(6): 4243-52, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25616695

RESUMO

Neither targeted therapies nor predictors for chemotherapy sensitivity are available for triple-negative breast cancer (TNBC). Our study included 187 patients with TNBC, 164 of whom were treated with anthracycline-based adjuvant chemotherapy. Eleven molecular biomarkers were analyzed. BCL2, epidermal growth factor receptor (EGFR), MYC, TOP2A, and Ki-67 protein expression was evaluated by immunohistochemistry. The status of the EGFR, MYC, and TOP2A genes and chromosomes 7, 8, and 17 was assessed using fluorescence in situ hybridization. High BCL2 expression predicted poor relapse-free survival (RFS) in patients treated with anthracycline-based adjuvant chemotherapy (p = 0.035), poor breast cancer-specific survival (BCSS) (p = 0.048), and a trend to poor overall survival (OS) (p = 0.085). High levels of BCL2 expression predicted poor OS in basal-like (BL) TNBC patients treated with adjuvant anthracycline-based regimens (log-rank p = 0.033, hazard ratio (HR) 3.04, 95 % confidence interval (CI) 1.04-8.91) and a trend to poor RFS (log-rank p = 0.079) and poor BCSS (log-rank p = 0.056). Multivariate analysis showed that BCL2 status, tumor size, and nodal status all had independent predictive significance for RFS (p = 0.005, p = 0.091, p = 0.003, respectively; likelihood ratio test for the whole model, p = 0.003), BCSS (p = 0.012, p = 0.077, p = 0.01, respectively; likelihood ratio test for the whole model, p = 0.016), and OS (p = 0.008, p = 0.004, p = 0.004, respectively; likelihood ratio test for the whole model, p = 0.0006). Similarly, multivariate analysis for BL TNBC showed BCL2, tumor size, and nodal status all had independent predictive significance for RFS (likelihood ratio test for the whole model, p = 0.00125), BCSS (p = 0.00035), and OS (p = 0.00063). High EGFR expression was associated with poor BCSS (p = 0.039) in patients treated with anthracycline-based adjuvant chemotherapy. Patients who underwent anthracycline-based adjuvant chemotherapy and exhibited CMYC amplification had a trend to worse BCSS (p = 0.066). In conclusion, high BCL2 expression is a significant independent predictor of poor outcome in TNBC patients treated with anthracycline-based adjuvant chemotherapy, and this is the first study showing the BCL2 prediction in BL TNBC. BCL2 expression analysis could facilitate decision making on adjuvant treatment in TNBC patients.


Assuntos
Antraciclinas/administração & dosagem , Recidiva Local de Neoplasia/genética , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Neoplasias de Mama Triplo Negativas/genética , Adulto , Idoso , Quimioterapia Adjuvante , Intervalo Livre de Doença , Receptores ErbB/biossíntese , Receptores ErbB/genética , Feminino , Humanos , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/patologia , Proteínas Proto-Oncogênicas c-bcl-2/genética , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/patologia
19.
BMC Cancer ; 15: 808, 2015 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-26508446

RESUMO

BACKGROUND: The anti-epidermal growth factor receptor (EGFR) monoclonal antibodies (moAbs) cetuximab or panitumumab are administered to colorectal cancer (CRC) patients who harbor wild-type RAS proto-oncogenes. However, a percentage of patients do not respond to this treatment. In addition to mutations in the RAS genes, mutations in other genes, such as BRAF, PI3KCA, or PTEN, could be involved in the resistance to anti-EGFR moAb therapy. METHODS: In order to develop a comprehensive approach for the detection of mutations and to eventually identify other genes responsible for resistance to anti-EGFR moAbs, we investigated a panel of 21 genes by parallel sequencing on the Ion Torrent Personal Genome Machine platform. We sequenced 65 CRCs that were treated with cetuximab or panitumumab. Among these, 37 samples were responsive and 28 were resistant. RESULTS: We confirmed that mutations in EGFR-pathway genes (KRAS, NRAS, BRAF, PI3KCA) were relevant for conferring resistance to therapy and could predict response (p = 0.001). After exclusion of KRAS, NRAS, BRAF and PI3KCA combined mutations could still significantly associate to resistant phenotype (p = 0.045, by Fisher exact test). In addition, mutations in FBXW7 and SMAD4 were prevalent in cases that were non-responsive to anti-EGFR moAb. After we combined the mutations of all genes (excluding KRAS), the ability to predict response to therapy improved significantly (p = 0.002, by Fisher exact test). CONCLUSIONS: The combination of mutations at KRAS and at the five gene panel demonstrates the usefulness and feasibility of multigene sequencing to assess response to anti-EGFR moAbs. The application of parallel sequencing technology in clinical practice, in addition to its innate ability to simultaneously examine the genetic status of several cancer genes, proved to be more accurate and sensitive than the presently in use traditional approaches.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Biomarcadores Tumorais/genética , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Receptores ErbB/antagonistas & inibidores , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados/farmacologia , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Cetuximab/farmacologia , Cetuximab/uso terapêutico , Neoplasias Colorretais/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Panitumumabe , Valor Preditivo dos Testes , Resultado do Tratamento
20.
Int J Mol Sci ; 16(10): 23382-9, 2015 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-26426010

RESUMO

Serum microRNAs are emerging as a clinically useful tool for early and non-invasive detection of various cancer types including renal cell carcinoma (RCC). Based on our previous results, we performed the study to analyze circulating serum miR-378 and miR-210 in patients with various histological subtypes of RCC. RNA was purified from blood serum samples of 195 RCC patients and 100 healthy controls. The levels of miR-378 and miR-210 in serum were determined absolutely using quantitative real-time PCR. Pre- and postoperative levels of both microRNAs were compared in 20 RCC patients. Significantly increased serum levels of both miR-378 and miR-210 enabled to clearly distinguish RCC patients and healthy controls with 80% sensitivity and 78% specificity if analyzed in combination (p<0.0001), and their levels significantly decreased in the time period of three months after radical nephrectomy (p<0.0001). Increased level of miR-378 positively correlates with disease-free survival (p=0.036) and clinical stage (p=0.0476). The analysis of serum miR-378 and miR-210 proved their potential to serve as powerful non-invasive diagnostic and prognostic biomarkers in RCC.


Assuntos
Carcinoma de Células Renais/sangue , Neoplasias Renais/sangue , MicroRNAs/sangue , Biomarcadores Tumorais/sangue , Carcinoma de Células Renais/genética , Estudos de Casos e Controles , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Renais/genética , Masculino , Pessoa de Meia-Idade
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