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1.
Cancer Immunol Immunother ; 69(4): 653-662, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32025849

RESUMO

Immune checkpoint inhibitors, including ipilimumab (IPI), achieve a clinical benefit in a small proportion of melanoma patients highlighting the need to investigate predictive biomarkers. In this study, we characterized tumor infiltrating lymphocytes (TILs), focusing on the CTLA-4+ subset, and evaluated their possible predictive significance. We characterized TIL density, cell type, and localization in 40 melanoma lesions from 17 patients treated with IPI. Associations of TILs with IPI timing, tissue localization, and response to IPI were estimated using a linear mixed-effects modelling approach. We found that most of TIL subsets increased in situ upon IPI therapy, with particular reference to FoxP3+ cells. TILs and TIL subsets, such as CD3+, CD45RO+, CTLA-4+, CD4+, CD8+ T cells, CD20+ B cells, and NKp46+ NK cells, showed significantly different spatial distributions in the tumor microenvironment being higher at the invasive margin (IM) as compared to the tumor center (TC) (P value < 0.001 for TIL score and P value < 0.05 for all subsets). Remarkably, high TIL score and density of CD3+, CD8+ T cells, and CTLA-4+ immune cells were significantly associated with a better response to IPI (P values = 0.002, 0.023, 0.007, and 0.001, respectively, for responders vs non-responders). In conclusion, we provide a detailed analysis of CTLA-4+ TIL distribution in melanoma tissues taking into account localization, relationship with CD3+/CD8+ TILs, and changes in response to IPI treatment. We identified that CTLA-4+ TILs may represent a marker of IPI response, alone or with CD3+/CD8+ subsets, although this requires confirmation in larger studies.


Assuntos
Antígeno CTLA-4/antagonistas & inibidores , Ipilimumab/uso terapêutico , Linfócitos do Interstício Tumoral/efeitos dos fármacos , Melanoma/tratamento farmacológico , Microambiente Tumoral/efeitos dos fármacos , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos Imunológicos/uso terapêutico , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Antígeno CTLA-4/imunologia , Antígeno CTLA-4/metabolismo , Feminino , Humanos , Células Matadoras Naturais/efeitos dos fármacos , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Masculino , Melanoma/imunologia , Melanoma/metabolismo , Pessoa de Meia-Idade , Estudos Retrospectivos , Microambiente Tumoral/imunologia
2.
Aging (Albany NY) ; 11(13): 4382-4406, 2019 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-31284268

RESUMO

Epigenetic mechanisms, such as DNA methylation, affect tubular maladaptive response after Acute Kidney Injury (AKI) and accelerate renal aging. Upon ischemia/reperfusion (I/R) injury, Complement activation leads to C5a release that mediates damage; however, little is known about the effect of C5a-C5a Receptor (C5aR) interaction in Renal Tubular Epithelial Cells (RTEC).Through a whole-genome DNA methylation analysis in cultured RTEC, we found that C5a induced aberrant methylation, particularly in regions involved in cell cycle control, DNA damage and Wnt signaling. The most represented genes were BCL9, CYP1B1 and CDK6. C5a stimulation of RTEC led to up-regulation of SA-ß Gal and cell cycle arrest markers such as p53 and p21. C5a increased also IL-6, MCP-1 and CTGF gene expression, consistent with SASP development. In accordance, in a swine model of renal I/R injury, we found the increased expression of Wnt4 and ßcatenin correlating with SA-ß Gal, p21, p16 and IL-6 positivity. Administration of Complement Inhibitor (C1-Inh), antagonized SASP by reducing SA-ß Gal, p21, p16, IL-6 and abrogating Wnt4/ßcatenin activation.Thus, C5a affects the DNA methylation of genes involved in tubular senescence. Targeting epigenetic programs and Complement may offer novels strategies to protect tubular cells from accelerated aging and to counteract progression to Chronic Kidney Disease.


Assuntos
Injúria Renal Aguda/metabolismo , Complemento C5a/fisiologia , Metilação de DNA , Túbulos Renais/metabolismo , Traumatismo por Reperfusão/metabolismo , Injúria Renal Aguda/etiologia , Células Cultivadas , Senescência Celular , Quinase 6 Dependente de Ciclina/metabolismo , Citocromo P-450 CYP1B1/metabolismo , Epigênese Genética , Células Epiteliais/metabolismo , Humanos , Traumatismo por Reperfusão/etiologia , Fatores de Transcrição/metabolismo , Via de Sinalização Wnt
3.
Cancers (Basel) ; 11(6)2019 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-31238504

RESUMO

Lysine histone demethylases (KDMs) are considered potential therapeutic targets in several tumors, including glioblastoma (GB). In particular, KDM5A is involved in the acquisition of temozolomide (TMZ) resistance in adult GB cells and UDX/KDM6B regulates H3K27 methylation, which is involved in the pediatric diffuse intrinsic pontine glioma (DIPG). Synthetic inhibitors of KDM5A (JIB 04 and CPI-455) efficiently block the proliferation of native and TMZ-resistant cells and the KDM6B inhibitor GSK J4 improves survival in a model of DIPG. The aim of our work was to determine if GSK J4 could be effective against GB cells that have acquired TMZ resistance and if it could synergize with TMZ or JIB 04 to increase the clinical utility of these molecules. Standard functional and pharmacological analytical procedures were utilized to determine the efficacy of the molecules under study when used alone or in combination against native GB cells and in a model of drug resistance. The results of this study indicated that although GSK J4 is active against native and TMZ-resistant cells, it does so at a lower efficacy than JIB 04. Drug combination studies revealed that GSK J4, differently from JIB 04, does not synergize with TMZ. Interestingly, GSK J4 and JIB 04 strongly synergize and are a potent combination against TMZ-resistant cells. Further studies in animal models will be necessary to determine if this combination of molecules might foster the development of novel therapeutic approaches for glioblastoma.

4.
Cancer Immunol Immunother ; 68(1): 97-107, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30311027

RESUMO

CTLA-4 blockade by means of ipilimumab (IPI) potentiates the immune response and improves overall survival (OS) in a minority of metastatic melanoma (MM) patients. We investigated the role of soluble CTLA-4 (sCTLA-4) as a possible biomarker for identifying this subset of patients. sCTLA-4 levels were analyzed at baseline in sera from 113 IPI-treated MM patients by ELISA, and the median value (200 pg/ml) was used to create two equally sized subgroups. Associations of sCTLA-4 with best overall response (BOR) to IPI and immune-related adverse events (irAEs) were evaluated through logistic regression. Kaplan-Meier and Cox regression methods were used to analyze OS. A remarkable association between sCTLA-4 levels and BOR was found. Specifically, the proportion of patients with sCTLA-4 > 200 pg/ml in irSD or irPD (immune-related stable or progressive disease) was, respectively, 80% (OR = 0.23; 95%CL = 0.03-1.88) and 89% (OR = 0.11; 95%CL = 0.02-0.71) and was lower than that observed among patients in irCR/irPR (immune-related complete/partial response). sCTLA-4 levels increased during IPI treatment, since the proportion of patients showing sCTLA > 200 pg/ml after 3 cycles was 4 times higher (OR = 4.41, 95%CL = 1.02-19.1) than that after 1 cycle. Moreover, a significantly lower death rate was estimated for patients with sCTLA-4 > 200 pg/ml (HR = 0.61, 95%CL = 0.39-0.98). Higher baseline sCTLA-4 levels were also associated with the onset of any irAE (p value = 0.029), in particular irAEs of the digestive tract (p value = 0.041). In conclusion, our results suggest that high sCTLA-4 serum levels might predict favorable clinical outcome and higher risk of irAEs in IPI-treated MM patients.


Assuntos
Biomarcadores Tumorais/metabolismo , Antígeno CTLA-4/metabolismo , Ipilimumab/uso terapêutico , Melanoma/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos Imunológicos/uso terapêutico , Biomarcadores Tumorais/sangue , Antígeno CTLA-4/sangue , Feminino , Humanos , Itália , Estimativa de Kaplan-Meier , Masculino , Melanoma/metabolismo , Melanoma/patologia , Pessoa de Meia-Idade , Metástase Neoplásica , Valor Preditivo dos Testes , Solubilidade , Adulto Jovem
5.
Front Oncol ; 8: 448, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30386738

RESUMO

Glioblastoma is one of the first tumors where the biological changes accompanying a single epigenetic modification, the methylation of the MGMT gene, were found to be of clinical relevance. The exploration of the epigenomic landscape of glioblastoma has allowed to identify patients carrying a diffuse hypermethylation at gene promoters and with better outcome. Epigenetic and genetic data have led to the definition of major subgroups of glioma and were the basis of the current WHO classification of CNS tumors and of a novel classification based solely on DNA methylation data that shows a remarkable diagnostic precision.The reversibility of epigenetic modifications is considered a therapeutic opportunity in many tumors also because these alterations have been mechanistically linked to the biological characteristics of glioblastoma. Several alterations like IDH1/2 mutations that interfere with "epigenetic modifier" enzymes, the mutations of the histone 3 variants H3.1 and H3.3 that alter the global H3K27me3 levels and the altered expression of histone methyltransferases and demethylases are considered potentially druggable targets in glioma and molecules targeting these alterations are being tested in preclinical and clinical trials. The recent advances on the knowledge of the players of the "epigenetic orchestra" and of their mutual interactions are indicating new paths that may eventually open new therapeutic options for this invariably lethal cancer.

6.
Front Oncol ; 8: 464, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30406030

RESUMO

Targeting the Immune Checkpoint molecules (ICs; CTLA-4, PD-1, PD-L1/2, and others) which provide inhibitory signals to T cells, dramatically improves survival in hard-to-treat tumors. The establishment of an immunosuppressive environment prevents endogenous immune response in glioblastoma; therefore, manipulating the host immune system seems a reasonable strategy also for this tumor. In glioma patients the accumulation of CD4+/CD8+ T cells and Treg expressing high levels of CTLA-4 and PD-1, or the high expression of PD-L1 in glioma cells correlates with WHO high grade and short survival. Few clinical studies with IC inhibitors (ICis) were completed so far. Notably, the first large-scale randomized trial (NCT 02017717) that compared PD-1 blockade and anti-VEGF, did not show an OS increase in the patients treated with anti-PD-1. Several factors could have contributed to the failure of this trial and must be considered to design further clinical studies. In particular the possibility of targeting at the same time different ICs was pre-clinically tested in an animal model were inhibitors against IDO, CTLA-4 and PD-L1 were combined and showed persistent and significant antitumor effects in glioma-bearing mice. It is reasonable to hypothesize that the immunological characterization of the tumor in terms of type and level of expressed IC molecules on the tumor and TIL may be useful to design the optimal ICi combination for a given subset of tumor to overcome the immunosuppressive milieu of glioblastoma and to efficiently target a tumor with such high cellular complexity.

8.
Genes Chromosomes Cancer ; 57(8): 387-400, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29689622

RESUMO

Uveal melanoma (UM) exhibits recurring chromosomal abnormalities and gene driver mutations, which are related to tumor evolution/progression. Almost half of the patients with UM develop distant metastases, predominantly to the liver, and so far there are no effective adjuvant therapies. An accurate UM genetic profile could assess the individual patient's metastatic risk, and provide the basis to determine an individualized targeted therapeutic strategy for each UM patient. To investigate the presence of specific chromosomal and gene alterations, BAP1 protein expression, and their relationship with distant progression free survival (DPFS), we analyzed tumor samples from 63 UM patients (40 men and 23 women, with a median age of 64 years), who underwent eye enucleation by a single cancer ophthalmologist from December 2005 to June 2016. UM samples were screened for the presence of losses/gains in chromosomes 1p, 3, 6p, and 8q, and for mutations in GNAQ, GNA11, BAP1, SF3B1, and EIF1AX. BAP1 protein expression was detected by immunohistochemistry (IHC). Multivariate analysis showed that the presence of monosomy 3, 8q gain, and loss of BAP1 protein were significantly associated to DPFS, while BAP1 gene mutation was not, mainly due to the presence of metastatic UM cases with negative BAP1 IHC and no BAP1 mutation detected by Sanger sequencing. Loss of BAP1 protein expression and monosomy 3 represent the strongest predictors of metastases, and may have important implications for implementation of patient surveillance, properly designed clinical trials enrollment, and adjuvant therapy.


Assuntos
Aberrações Cromossômicas , Melanoma/genética , Mutação , Proteínas Supressoras de Tumor/genética , Ubiquitina Tiolesterase/genética , Neoplasias Uveais/genética , Idoso , Deleção Cromossômica , Cromossomos Humanos Par 3/genética , Análise Mutacional de DNA , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Melanoma/metabolismo , Melanoma/mortalidade , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Transcriptoma , Proteínas Supressoras de Tumor/biossíntese , Ubiquitina Tiolesterase/biossíntese , Neoplasias Uveais/metabolismo , Neoplasias Uveais/mortalidade
10.
Int J Genomics ; 2017: 7639084, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29234674

RESUMO

Glioblastoma is the most aggressive brain tumor and, even with the current multimodal therapy, is an invariably lethal cancer with a life expectancy that depends on the tumor subtype but, even in the most favorable cases, rarely exceeds 2 years. Epigenetic factors play an important role in gliomagenesis, are strong predictors of outcome, and are important determinants for the resistance to radio- and chemotherapy. The latest addition to the epigenetic machinery is the noncoding RNA (ncRNA), that is, RNA molecules that are not translated into a protein and that exert their function by base pairing with other nucleic acids in a reversible and nonmutational mode. MicroRNAs (miRNA) are a class of ncRNA of about 22 bp that regulate gene expression by binding to complementary sequences in the mRNA and silence its translation into proteins. MicroRNAs reversibly regulate transcription through nonmutational mechanisms; accordingly, they can be considered as epigenetic effectors. In this review, we will discuss the role of miRNA in glioma focusing on their role in drug resistance and on their potential applications in the therapy of this tumor.

11.
Front Immunol ; 8: 386, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28446908

RESUMO

Ipilimumab (IPI) blocks CTLA-4 immune checkpoint resulting in T cell activation and enhanced antitumor immunity. IPI improves overall survival (OS) in 22% of patients with metastatic melanoma (MM). We investigated the association of CTLA-4 single nucleotide variants (SNVs) with best overall response (BOR) to IPI and OS in a cohort of 173 MM patients. Patients were genotyped for six CTLA-4 SNVs (-1661A>G, -1577G>A, -658C>T, -319C>T, +49A>G, and CT60G>A). We assessed the association between SNVs and BOR through multinomial logistic regression (MLR) and the prognostic effect of SNVs on OS through Kaplan-Meier method. Both -1577G>A and CT60G>A SNVs were found significantly associated with BOR. In particular, the proportion of responders was higher in G/G genotype while that of stable patients was higher in A/A genotype. The frequency of patients experiencing progression was similar in all genotypes. MLR evidenced a strong downward trend in the probability of responsiveness/progression, in comparison to disease stability, as a function of the allele A "dose" (0, 1, or 2) in both SNVs with reductions of about 70% (G/A vs G/G) and about 95% (A/A vs G/G). Moreover, -1577G/G and CT60G/G genotypes were associated with long-term OS, the surviving patients being at 3 years 29.8 and 30.8%, respectively, as compared to 12.9 and 14.4% of surviving patients carrying -1577G/A and CT60G/A, respectively. MM patients carrying -1577G/G or CT60G/G genotypes may benefit from IPI treatment in terms of BOR and long-term OS. These CTLA-4 SNVs may serve as potential biomarkers predictive of favorable outcome in this subset of patients.

12.
Oncotarget ; 8(21): 34896-34910, 2017 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-28432280

RESUMO

In glioblastoma several histone demethylase genes (KDM) are overexpressed compared to normal brain tissue and the development of Temozolomide (TMZ) resistance is accompanied by the transient further increased expression of KDM5A and other KDMs following a mechanism that we defined as "epigenetic resilience". We hypothesized that targeting KDMs may kill the cells that survive the cytotoxic therapy.We determined the effect of JIB 04 and CPI-455, two KDM inhibitors, on glioblastoma cells and found that both molecules are more effective against TMZ-resistant rather than native cells.Because of its lower IC50, we focused on JIB 04 that targets KDM5A and other KDMs as well. We have shown that this molecule activates autophagic and apoptotic pathways, interferes with cell cycle progression, inhibits cell clonogenicity and dephosphorylates Akt thus inactivating a potent pro-survival pathway. We performed combination temozolomide/JIB 04 in vitro treatments showing that these two molecules, under certain conditions, have a strong synergic effect and we hypothesize that JIB 04 intercepts the cells that escape the G2 block exerted by TMZ. Finally we studied the permeability of JIB 04 across the blood-brain barrier and found that this molecule reaches bioactive concentration in the brain; furthermore a pilot in vivo experiment in an orthotopic GB xenograft model showed a trend toward longer survival in treated mice with an Hazard Ratio of 0.5.In conclusion we propose that the combination between cytotoxic drugs and molecules acting on the epigenetic landscape may offer the opportunity to develop new therapies for this invariably lethal disease.


Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Dacarbazina/análogos & derivados , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Inibidores Enzimáticos/administração & dosagem , Glioblastoma/tratamento farmacológico , Bibliotecas de Moléculas Pequenas/administração & dosagem , Aminopiridinas/administração & dosagem , Aminopiridinas/farmacologia , Animais , Barreira Hematoencefálica/efeitos dos fármacos , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Dacarbazina/administração & dosagem , Dacarbazina/farmacologia , Sinergismo Farmacológico , Inibidores Enzimáticos/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioblastoma/metabolismo , Histona Desmetilases/antagonistas & inibidores , Humanos , Hidrazonas/administração & dosagem , Hidrazonas/farmacologia , Camundongos , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteína 2 de Ligação ao Retinoblastoma/antagonistas & inibidores , Proteína 2 de Ligação ao Retinoblastoma/genética , Bibliotecas de Moléculas Pequenas/farmacologia , Temozolomida , Ensaios Antitumorais Modelo de Xenoenxerto
13.
Oncotarget ; 7(50): 83330-83341, 2016 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-27829219

RESUMO

Neuroblastoma is the most common human extracranial solid tumor during infancy. Involvement of several miRNAs in its pathogenesis has been ascertained. Interestingly, most of their encoding genes reside in hypermethylated genomic regions: thus, their tumor suppressor function is normally disallowed in these tumors. To date, the therapeutic role of the demethylating agent 5'-Aza-2 deoxycytidine (5'-AZA) and its effects on miRNAome modulation in neuroblastoma have not been satisfactorily explored. Starting from a high-throughput expression profiling of 754 miRNAs and based on a proper selection, we focused on miR-29a-3p, miR-34b-3p, miR-181c-5p and miR-517a-3p as candidate miRNAs for our analysis. They resulted downregulated in four neuroblastoma cell lines with respect to normal adrenal gland. MiRNAs 29a-3p and 34b-3p also resulted downregulated in vivo in a murine neuroblastoma progression model. Unlike the amount of methylation of their encoding gene promoters, all these miRNAs were significantly overexpressed following treatment with 5'-AZA. Transfection with candidate miRNAs mimics significantly decreased neuroblastoma cells proliferation rate. A lower expression of miR-181c was significantly associated to a worse overall survival in a public dataset of 498 neuroblastoma samples (http://r2.amc.nl). Our data strongly suggest that CDK6, DNMT3A, DNMT3B are targets of miR-29a-3p, while CCNE2 and E2F3 are targets of miR-34b-3p. Based on all these data, we propose that miR-29a-3p, miR-34b-3p, miR-181c-5p and miR-517a-3p are disallowed tumor suppressor genes in neuroblastoma and suggest them as new therapeutic targets in neuroblastoma.


Assuntos
Metilação de DNA , Epigênese Genética , MicroRNAs/genética , Neuroblastoma/genética , Regiões Promotoras Genéticas , Animais , Azacitidina/análogos & derivados , Azacitidina/farmacologia , Linhagem Celular Tumoral , Proliferação de Células , Biologia Computacional , Ilhas de CpG , Metilação de DNA/efeitos dos fármacos , Metilases de Modificação do DNA/antagonistas & inibidores , Metilases de Modificação do DNA/metabolismo , Bases de Dados Genéticas , Decitabina , Inibidores Enzimáticos/farmacologia , Epigênese Genética/efeitos dos fármacos , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Predisposição Genética para Doença , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Estimativa de Kaplan-Meier , Camundongos , MicroRNAs/metabolismo , Neuroblastoma/metabolismo , Neuroblastoma/mortalidade , Neuroblastoma/terapia , Fenótipo , Prognóstico , Mapas de Interação de Proteínas , Transdução de Sinais , Fatores de Tempo
14.
Biochim Biophys Acta ; 1859(12): 1502-1514, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27751904

RESUMO

In neuroblastoma, the epigenetic landscape is more profoundly altered in aggressive compared to lower grade tumors and the concomitant hypermethylation of many genes, defined as "methylator phenotype", has been associated with poor outcome. DNA methylation can interfere with gene expression acting at distance through the methylation or demethylation of the regulatory regions of miRNAs. The multiplicity of miRNA targets may result in the simultaneous alteration of many biological pathways like cell proliferation, apoptosis, migration and differentiation. We have analyzed the methylation status of a set of miRNAs in a panel of neuroblastoma cell lines and identified a subset of hypermethylated and down-regulated miRNAs (miRNA 34b-3p, miRNA 34b-5p, miRNA34c-5p, and miRNA 124-2-3p) involved in the regulation of cell cycle, apoptosis and in the control of MYCN expression. These miRNAs share, in part, some of the targets whose expression is inversely correlated to the methylation and expression of the corresponding miRNA. To simulate the effect of the demethylation of miRNAs, we transfected the corresponding miRNA-mimics in the same cell lines and observed the down-regulation of a set of their target genes as well as the partial block of the cell cycle and the activation of the apoptotic pathway. The epigenetic alterations of miRNAs described in the present study were found also in a subset of patients at high risk of progression. Our data disclosed a complex network of interactions between epigenetically altered miRNAs and target genes, that could interfere at multiple levels in the control of cell homeostasis.


Assuntos
Metilação de DNA/genética , Epigênese Genética , MicroRNAs/genética , Neuroblastoma/genética , Apoptose/genética , Diferenciação Celular/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , MicroRNAs/classificação , Neuroblastoma/patologia , Fatores de Risco , Análise de Sobrevida
15.
Cancer Immunol Immunother ; 65(8): 909-17, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27207606

RESUMO

CTLA-4 function as a negative regulator of T cell-mediated immune response is well established, whereas much less is known about the immunoregulatory role of its soluble isoform (sCTLA-4). No data are available on CTLA-4 expression and prognostic impact in malignant pleural mesothelioma (MPM). We investigated, by immunohistochemistry, CTLA-4 expression in tumor tissues and, by ELISA, sCTLA-4 levels in sera and matched pleural effusions from 45 MPM patients. Prognostic effect of CTLA-4 expression on overall survival (OS) was assessed through Cox regression and prognostic significance expressed as death rate ratio (HR). We found that 56.0 % of MPM tissues expressed CTLA-4 with variable intensity and percentage of positive cells estimated by the immunoreactive score. sCTLA-4 levels were significantly higher in sera (S-sCTLA-4) than in pleural effusions (PE-sCTLA-4) (geometric mean ratio = 2.70, P value = 0.020). CTLA-4 expression at the tissue level was higher in the epithelioid histological subtype than in the sarcomatoid, whereas at the serum level, it was higher in the sarcomatoid subtype. A homogeneous favorable prognostic effect was found for CTLA-4 overexpression in tissue, serum and pleural effusion. Interestingly, only the PE-sCTLA-4 was found to be a statistically significant positive prognostic factor (HR = 0.37, 95 % CI = 0.18-0.77, P value = 0.007). Indeed, PE-sCTLA-4 correlated with CTLA-4 expression in tissues, whereas this latter expression showed a weak association with OS. To confirm our findings, further experimental evidences obtained from a larger cohort of MPM patients are required. However, our results would indicate a positive correlation of PE-sCTLA-4 levels and OS in MPM patients.


Assuntos
Antígeno CTLA-4/metabolismo , Mesotelioma/genética , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Mesotelioma/mortalidade , Mesotelioma/patologia , Pessoa de Meia-Idade , Prognóstico , Análise de Sobrevida
17.
Oncotarget ; 7(4): 4746-59, 2016 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-26683098

RESUMO

MiR-671-5p is encoded by a gene localized at 7q36.1, a region amplified in human glioblastoma multiforme (GBM), the most malignant brain cancer. To investigate whether expression of miR-671-5p were altered in GBM, we analyzed biopsies from a cohort of forty-five GBM patients and from five GBM cell lines. Our data show significant overexpression of miR-671-5p in both biopsies and cell lines. By exploiting specific miRNA mimics and inhibitors, we demonstrated that miR-671-5p overexpression significantly increases migration and to a less extent proliferation rates of GBM cells. Through a combined in silico and in vitro approach, we identified CDR1-AS, CDR1, VSNL1 as downstream miR-671-5p targets in GBM. Expression of these genes significantly decreased both in GBM biopsies and cell lines and negatively correlated with that of miR-671-5p. Based on our data, we propose that the axis miR-671-5p / CDR1-AS / CDR1 / VSNL1 is functionally altered in GBM cells and is involved in the modification of their biopathological profile.


Assuntos
Autoantígenos/metabolismo , Neoplasias Encefálicas/genética , Encéfalo/metabolismo , Glioblastoma/genética , MicroRNAs/genética , Proteínas do Tecido Nervoso/metabolismo , Neurocalcina/metabolismo , Apoptose , Autoantígenos/genética , Biomarcadores Tumorais , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Estudos de Casos e Controles , Proliferação de Células , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Estadiamento de Neoplasias , Proteínas do Tecido Nervoso/genética , Neurocalcina/genética , Prognóstico , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas , Cicatrização
18.
Cell Cycle ; 14(21): 3418-29, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26566863

RESUMO

Notwithstanding current multimodal treatment, including surgery, radiotherapy and chemotherapy with temozolomide (TMZ), median survival of glioblastoma (GBM) patients is about 14 months, due to the rapid emergence of cell clones resistant to treatment. Therefore, understanding the mechanisms underlying chemoresistance is mandatory to improve treatments' outcome. We generated TMZ resistant cells (TMZ-R) from a GBM cell line and from cancer stem cell-enriched cultures isolated from human GBMs. We demonstrated that TMZ resistance is partially reverted by "drug wash-out" suggesting the contribution of epigenetic mechanisms in drug resistance and supporting the possibility of TMZ rechallenge in GBM patients after prior drug exposure. The expression of histone lysine demethylase genes (KDMs) was increased in TMZ-R cells compared to parental cells, and TMZ resistance or restored sensitivity was mimicked by over-expressing or inactivating KDM5A. Methylation and expression of O6-methylguanine-DNA methyltransferase (MGMT) and drug efflux mechanisms were not altered in TMZ-R cells compared to parental TMZ sensitive cells. TMZ-R cells transiently acquired morphologic and molecular characteristics of differentiated tumor cells, features that were lost after drug wash-out. In conclusion, we demonstrated that treatment-induced TMZ resistance in GBM involves epigenetic mechanisms in a subset of slow-cycling and transiently partially differentiated cells that escape drug cytotoxicity, overcome G2 checkpoint and sustain clonal growth. We found that TMZ-R cells are sensitive to histone deacethylase inhibitors (HDACi) that synergize with TMZ. This strong synergism could be exploited to develop novel combined adjuvant therapies for this rapidly progressing and invariably lethal cancer.


Assuntos
Antineoplásicos Alquilantes/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Dacarbazina/análogos & derivados , Resistencia a Medicamentos Antineoplásicos , Glioblastoma/tratamento farmacológico , Células-Tronco Neoplásicas/efeitos dos fármacos , Proteína 2 de Ligação ao Retinoblastoma/metabolismo , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias Encefálicas/enzimologia , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Ciclo Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Forma Celular/efeitos dos fármacos , Metilação de DNA/efeitos dos fármacos , Dacarbazina/farmacologia , Relação Dose-Resposta a Droga , Resistencia a Medicamentos Antineoplásicos/genética , Sinergismo Farmacológico , Epigênese Genética/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Genótipo , Glioblastoma/enzimologia , Glioblastoma/genética , Glioblastoma/patologia , Inibidores de Histona Desacetilases/farmacologia , Humanos , Células-Tronco Neoplásicas/enzimologia , Células-Tronco Neoplásicas/patologia , Fenótipo , Interferência de RNA , Proteína 2 de Ligação ao Retinoblastoma/antagonistas & inibidores , Proteína 2 de Ligação ao Retinoblastoma/genética , Temozolomida , Fatores de Tempo , Transfecção
19.
J Transl Med ; 13: 324, 2015 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-26450443

RESUMO

BACKGROUND: Trastuzumab is a humanized monoclonal antibody (mAb) currently used for the treatment of breast cancer (BC) patients with HER-2 overexpressing tumor subtype. Previous data reported the involvement of FcγRIIIA/IIA gene polymorphisms and/or antibody-dependent cellular cytotoxicity (ADCC) in the therapeutic efficacy of trastuzumab, although results on these issues are still controversial. This study was aimed to evaluate in vitro the functional relationships among FcγRIIIA/IIA polymorphisms, ADCC intensity and HER-2 expression on tumor target cells and to correlate them with response to trastuzumab. PATIENTS AND METHODS: Twenty-five patients with HER-2 overexpressing BC, receiving trastuzumab in a neoadjuvant (NEO) or metastatic (MTS) setting, were genotyped for the FcγRIIIA 158V>F and FcγRIIA 131H>R polymorphisms by a newly developed pyrosequencing assay and by multiplex Tetra-primer-ARMS PCR, respectively. Trastuzumab-mediated ADCC of patients' peripheral blood mononuclear cells (PBMCs) was evaluated prior to therapy and measured by (51)Chromium release using as targets three human BC cell lines showing different levels of reactivity with trastuzumab. RESULTS: We found that the FcγRIIIA 158F and/or the FcγRIIA 131R variants, commonly reported as unfavorable in BC, may actually behave as ADCC favorable genotypes, in both the NEO (P ranging from 0.009 to 0.039 and from 0.007 to 0.047, respectively) and MTS (P ranging from 0.009 to 0.032 and P = 0.034, respectively) patients. The ADCC intensity was affected by different levels of trastuzumab reactivity with BC target cells. In this context, the MCF-7 cell line, showing the lowest reactivity with trastuzumab, resulted the most suitable cell line for evaluating ADCC and response to trastuzumab. Indeed, we found a statistically significant correlation between an increased frequency of patients showing ADCC of MCF-7 and complete response to trastuzumab in the NEO setting (P = 0.006). CONCLUSIONS: Although this study was performed in a limited number of patients, it would indicate a correlation of FcγR gene polymorphisms to the ADCC extent in combination with the HER-2 expression levels on tumor target cells in BC patients. However, to confirm our findings further experimental evidences obtained from a larger cohort of BC patients are mandatory.


Assuntos
Citotoxicidade Celular Dependente de Anticorpos/imunologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Receptor ErbB-2/metabolismo , Receptores de IgG/genética , Trastuzumab/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/uso terapêutico , Neoplasias da Mama/metabolismo , Estudos de Casos e Controles , Linhagem Celular Tumoral , Estudos de Coortes , Feminino , Citometria de Fluxo , Frequência do Gene , Genótipo , Humanos , Imuno-Histoquímica , Células K562 , Leucócitos Mononucleares/citologia , Células MCF-7 , Pessoa de Meia-Idade , Metástase Neoplásica , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA
20.
Biomed Res Int ; 2015: 587983, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26339624

RESUMO

Epigenetics provides the key to transform the genetic information into phenotype and because of its reversibility it is considered an ideal target for therapeutic interventions. This paper reviews the basic mechanisms of epigenetic control: DNA methylation, histone modifications, chromatin remodeling, and ncRNA expression and their role in disease development. We describe also the influence of the environment, lifestyle, nutritional habits, and the psychological influence on epigenetic marks and how these factors are related to cancer and other diseases development. Finally we discuss the potential use of natural epigenetic modifiers in the chemoprevention of cancer to link together public health, environment, and lifestyle.


Assuntos
Metilação de DNA/genética , Meio Ambiente , Epigenômica , Neoplasias/genética , Cromatina/genética , Histonas/metabolismo , Humanos , Estilo de Vida , Neoplasias/epidemiologia , Neoplasias/prevenção & controle , Fenótipo , Saúde Pública
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