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1.
Invest New Drugs ; 40(6): 1185-1193, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35976541

RESUMO

Macrocyclic compounds meso-(p-acetamidophenyl)-calix[4]pyrrole and meso-(m-acetamidophenyl)-calix[4]pyrrole have previously been reported to exhibit cytotoxic properties towards lung cancer cells. Here, we report pre-clinical in vitro and in vivo studies showing that these calixpyrrole derivatives can inhibit cell growth in both PC3 and DU145 prostatic cancer cell lines. We explored the impact of these compounds on programmed cell death, as well as their ability to inhibit cellular invasion. In this study we have demonstrated the safety of these macrocyclic compounds by cytotoxicity tests on ex-vivo human peripheral blood mononuclear cells (PBMCs), and by in vivo subcutaneous administration. Preliminary in vivo tests demonstrated no hepato-, no nephro- and no genotoxicity in Balb/c mice compared to controls treated with cisplatin. These findings suggest these calixpyrroles might be novel therapeutic tools for the treatment of prostate cancer and of particular interest for the treatment of androgen-independent castration-resistant prostate cancer.


Assuntos
Antineoplásicos , Poríferos , Neoplasias de Próstata Resistentes à Castração , Masculino , Camundongos , Animais , Humanos , Pirróis/uso terapêutico , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/metabolismo , Linhagem Celular Tumoral , Leucócitos Mononucleares , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Camundongos Endogâmicos BALB C
2.
Clin Immunol ; 215: 108428, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32344017

RESUMO

The expression of the immune checkpoint molecule CTLA-4 has been almost exclusively studied in the T cell lineage, but increasing evidence has shown its expression on tumors with implications for immunotherapy. To date, the degree of expression of CTLA-4 on tumor cells as a predictive biomarker of response to immune checkpoint inhibitors has not been studied. In this report, we analyzed this issue in melanoma patients treated with CTLA-4 inhibitor Ipilimumab (IPI). We show that the level of CTLA-4 expression on melanoma cells is higher than that on tumor infiltrating lymphocytes (TIL) and it is associated with clinical response to IPI therapy supporting the idea of its possible role as a predictive biomarker.


Assuntos
Antineoplásicos Imunológicos/uso terapêutico , Antígeno CTLA-4/metabolismo , Ipilimumab/uso terapêutico , Melanoma/tratamento farmacológico , Melanoma/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/metabolismo , Feminino , Humanos , Imunoterapia/métodos , Masculino , Pessoa de Meia-Idade
3.
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
4.
Molecules ; 25(22)2020 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-33198146

RESUMO

Colorectal cancer is a malignancy with a high incidence. Currently, the drugs used in chemotherapy are often accompanied by strong side effects. Natural secondary metabolites can interfere with chemotherapeutic drugs and intensify their cytotoxic effects. This study aimed to profile the secondary metabolites from the methanol extract of Scabiosa atropurpurea and investigate their in vitro activities, alone or in combination with the chemotherapeutic agent doxorubicin. MTT assay was used to determine the cytotoxic activities. Annexin-V/PI double-staining analysis was employed to evaluate the apoptotic concentration. Multicaspase assay, quantitative reverse transcription real-time PCR (RT-qPCR), and ABC transporter activities were also performed. LC-MS analysis revealed 31 compounds including phenolic acids, flavonoids, and saponins. S. atropurpurea extract intensified doxorubicin anti-proliferative effects against resistant tumor cells and enhanced the cytotoxic effects towards Caco-2 cells after 48 h. The mRNA expression levels of Bax, caspase-3, and p21 were increased significantly whereas Bcl-2 expression level was decreased. Furthermore, the methanol extract reversed P-glycoprotein or multidrug resistance-associated protein in Caco-2 cells. In conclusion, S. atropurpurea improved chemosensitivity and modulated multidrug resistance in Caco-2 cells which makes it a good candidate for further research in order to develop a new potential cancer treatment.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Neoplasias Colorretais/patologia , Dipsacaceae/química , Doxorrubicina/administração & dosagem , Doxorrubicina/farmacologia , Resistencia a Medicamentos Antineoplásicos , Extratos Vegetais/farmacologia , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Apoptose , Células CACO-2 , Caspases/metabolismo , Proliferação de Células , Neoplasias Colorretais/tratamento farmacológico , Combinação de Medicamentos , Resistência a Múltiplos Medicamentos , Humanos , Concentração Inibidora 50 , Metanol/química , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Folhas de Planta/química , Polifenóis/química
5.
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
6.
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
7.
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
8.
Clin Sci (Lond) ; 130(9): 733-46, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26846681

RESUMO

IgAN (IgA nephropathy) is the most common form of primary glomerulonephritis worldwide and has a strong genetic component. In this setting, DNA methylation could also be an important factor influencing this disease. We performed a genome-wide screening for DNA methylation in CD4(+) T-cells from IgAN patients and found three regions aberrantly methylated influencing genes involved in the response and proliferation of CD4(+) T-cells. Two hypomethylated regions codified genes involved in TCR (T-cell receptor) signalling, TRIM27 (tripartite motif-containing 27) and DUSP3 (dual-specificity phosphatase 3), and an hypermethylated region included the VTRNA2-1 (vault RNA 2-1) non-coding RNA, also known as miR-886 precursor. We showed that the aberrant methylation influences the expression of these genes in IgAN patients. Moreover, we demonstrated that the hypermethylation of the miR-886 precursor led to a decreased CD4(+) T-cell proliferation following TCR stimulation and to the overexpression of TGFß (transforming growth factor ß). Finally, we found a Th1/Th2 imbalance in IgAN patients. The IL (interleukin)-2/IL-5 ratio was notably higher in IgAN patients and clearly indicated a Th1 shift. In conclusion, we identified for the first time some specific DNA regions abnormally methylated in IgAN patients that led to the reduced TCR signal strength of the CD4(+) T-cells and to their anomalous response and activation that could explain the T-helper cell imbalance. The present study reveals new molecular mechanisms underlying the abnormal CD4(+) T-cell response in IgAN patients.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Metilação de DNA/genética , Glomerulonefrite por IGA/genética , Glomerulonefrite por IGA/imunologia , Ativação Linfocitária/imunologia , Adulto , Estudos de Casos e Controles , Linhagem Celular , Ilhas de CpG/genética , Demografia , Feminino , Regulação da Expressão Gênica , Genoma Humano , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes
9.
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
10.
Int J Mol Sci ; 16(12): 28765-82, 2015 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-26633390

RESUMO

Next-generation sequencing (NGS) is a cost-effective technology capable of screening several genes simultaneously; however, its application in a clinical context requires an established workflow to acquire reliable sequencing results. Here, we report an optimized NGS workflow analyzing 22 lung cancer-related genes to sequence critical samples such as DNA from formalin-fixed paraffin-embedded (FFPE) blocks and circulating free DNA (cfDNA). Snap frozen and matched FFPE gDNA from 12 non-small cell lung cancer (NSCLC) patients, whose gDNA fragmentation status was previously evaluated using a multiplex PCR-based quality control, were successfully sequenced with Ion Torrent PGM™. The robust bioinformatic pipeline allowed us to correctly call both Single Nucleotide Variants (SNVs) and indels with a detection limit of 5%, achieving 100% specificity and 96% sensitivity. This workflow was also validated in 13 FFPE NSCLC biopsies. Furthermore, a specific protocol for low input gDNA capable of producing good sequencing data with high coverage, high uniformity, and a low error rate was also optimized. In conclusion, we demonstrate the feasibility of obtaining gDNA from FFPE samples suitable for NGS by performing appropriate quality controls. The optimized workflow, capable of screening low input gDNA, highlights NGS as a potential tool in the detection, disease monitoring, and treatment of NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Biologia Computacional/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Neoplasias Pulmonares/genética , Adulto , Idoso , Carcinoma Pulmonar de Células não Pequenas/patologia , Biologia Computacional/normas , Humanos , Neoplasias Pulmonares/patologia , Pessoa de Meia-Idade , Mutação , Estadiamento de Neoplasias , Polimorfismo de Nucleotídeo Único , Controle de Qualidade , Sensibilidade e Especificidade , Fluxo de Trabalho
11.
Arch Dermatol Res ; 316(7): 414, 2024 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-38880834

RESUMO

Previous studies showed an association between single nucleotide gene variants (SNVs) of PD-1 and cancer susceptibility. We analyzed PD1.5 C > T and PD1.7 T > C SNVs to investigate their association with the risk of developing metastatic melanoma (MM). Utilizing a cohort of 125 MM patients treated with anti-PD-1 agents and 84 healthy controls, we examined genotype/allele frequencies through a modified Poisson regression model, adjusted for age and sex. Our findings indicate that the PD1.5 T allele is associated with a reduced risk of MM, showing a significantly lower risk in both codominant (RR = 0.56, 95%CL: 0.37-0.87) and dominant (RR = 0.73 95%CL: 0.59-0.90) models. Conversely, the PD1.7 C allele is linked to an increased risk of MM, with the C/C genotype exhibiting a higher risk in the codominant (RR = 1.65, 95%CL: 1.32-2.05) and allelic (RR = 1.23, 95%CL: 1.06-1.43) models. These results are consistent with previous meta-analyses on other cancer types, mainly highlighting the PD1.5 SNV's potential role in promoting anti-tumor immunity through increased PD1-positive circulating effector T cell activity.


Assuntos
Frequência do Gene , Predisposição Genética para Doença , Melanoma , Polimorfismo de Nucleotídeo Único , Receptor de Morte Celular Programada 1 , Neoplasias Cutâneas , Humanos , Melanoma/genética , Receptor de Morte Celular Programada 1/genética , Feminino , Masculino , Pessoa de Meia-Idade , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia , Idoso , Estudos de Casos e Controles , Adulto , Genótipo , Inibidores de Checkpoint Imunológico/uso terapêutico , Alelos
12.
Int J Mol Sci ; 14(4): 7492-505, 2013 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-23567267

RESUMO

Medulloblastoma (MB) is a malignant pediatric brain tumor arising in the cerebellum consisting of four distinct subgroups: WNT, SHH, Group 3 and Group 4, which exhibit different molecular phenotypes. We studied the expression of Dickkopf (DKK) 1-4 family genes, inhibitors of the Wnt signaling cascade, in MB by screening 355 expression profiles derived from four independent datasets. Upregulation of DKK1, DKK2 and DKK4 mRNA was observed in the WNT subgroup, whereas DKK3 was downregulated in 80% MBs across subgroups with respect to the normal cerebellum (p < 0.001). Since copy number aberrations targeting the DKK3 locus (11p15.3) are rare events, we hypothesized that epigenetic factors could play a role in DKK3 regulation. Accordingly, we studied 77 miRNAs predicting to repress DKK3; however, no significant inverse correlation between miRNA/mRNA expression was observed. Moreover, the low methylation levels in the DKK3 promoters (median: 3%, 5% and 5% for promoter 1, 2 and 3, respectively) excluded the downregulation of gene expression by methylation. On the other hand, the treatment of MB cells with Trichostatin A (TSA), a potent inhibitor of histone deacetylases (HDAC), was able to restore both DKK3 mRNA and protein. In conclusion, DKK3 downregulation across all MB subgroups may be due to epigenetic mechanisms, in particular, through chromatin condensation.


Assuntos
Montagem e Desmontagem da Cromatina , Regulação Neoplásica da Expressão Gênica , Inativação Gênica , Peptídeos e Proteínas de Sinalização Intercelular/biossíntese , Meduloblastoma/metabolismo , Proteínas de Neoplasias/biossíntese , Proteínas Adaptadoras de Transdução de Sinal , Adolescente , Adulto , Idoso , Linhagem Celular Tumoral , Quimiocinas , Criança , Pré-Escolar , Bases de Dados Genéticas , Feminino , Perfilação da Expressão Gênica , Humanos , Lactente , Peptídeos e Proteínas de Sinalização Intercelular/genética , Masculino , Meduloblastoma/genética , Meduloblastoma/patologia , Metilação , Pessoa de Meia-Idade , Proteínas de Neoplasias/genética , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , RNA Neoplásico/biossíntese
13.
J Mol Diagn ; 25(4): 217-226, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36739964

RESUMO

Epithelial ovarian cancers (EOCs) harboring germline or somatic pathogenic variants in BRCA1 and BRCA2 genes show sensitivity to poly(ADP-ribose) polymerase inhibition. It has been suggested that BRCA1 promoter methylation is perhaps a better determinant of therapy response, because of its intrinsic dynamic feature, with respect to genomic scars or gene mutation. Conflicting evidence was reported so far, and the lack of a validated assay to measure promoter methylation was considered a main confounding factor in data interpretation. To contribute to the validation process of a pyrosequencing assay for BRCA1 promoter methylation, 109 EOCs from two Italian centers were reciprocally blindly investigated. By comparing two different pyrosequencing assays, addressing a partially overlapping region of BRCA1 promoter, an almost complete concordance of results was obtained. Moreover, the clinical relevance of this approach was also supported by the finding of BRCA1 transcript down-regulation in BRCA1-methylated EOCs. These findings could lead to the development of a simple and cheap pyrosequencing assay for diagnostics, easily applicable to formalin-fixed, paraffin-embedded tissues. This technique may be implemented in routine clinical practice in the near future to identify EOCs sensitive to poly(ADP-ribose) polymerase inhibitor therapy, thus increasing the subset of women affected by EOCs who could benefit from such treatment.


Assuntos
Antineoplásicos , Neoplasias Ovarianas , Feminino , Humanos , Mutação em Linhagem Germinativa , Proteína BRCA1/genética , Mutação , Metilação de DNA/genética , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Antineoplásicos/uso terapêutico , Sequenciamento de Nucleotídeos em Larga Escala , Neoplasias Ovarianas/diagnóstico , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/tratamento farmacológico , Proteína BRCA2/genética
14.
J Exp Clin Cancer Res ; 42(1): 67, 2023 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-36934257

RESUMO

BACKGROUND: The combination of Programmed Cell Death 1 (PD-1) and Cytotoxic T-Lymphocyte Antigen 4 (CTLA-4) blockade has dramatically improved the overall survival rate for malignant melanoma. Immune checkpoint blockers (ICBs) limit the tumor's immune escape yet only for approximately a third of all tumors and, in most cases, for a limited amount of time. Several approaches to overcome resistance to ICBs are being investigated among which the addition of epigenetic drugs that are expected to act on both immune and tumor cells. Guadecitabine, a dinucleotide prodrug of a decitabine linked via phosphodiester bond to a guanosine, showed promising results in the phase-1 clinical trial, NIBIT-M4 (NCT02608437). METHODS: We used the syngeneic B16F10 murine melanoma model to study the effects of immune checkpoint blocking antibodies against CTLA-4 and PD-1 in combination, with and without the addition of Guadecitabine. We comprehensively characterized the tumor's and the host's responses under different treatments by flow cytometry, multiplex immunofluorescence and methylation analysis. RESULTS: In combination with ICBs, Guadecitabine significantly reduced subcutaneous tumor growth as well as metastases formation compared to ICBs and Guadecitabine treatment. In particular, Guadecitabine greatly enhanced the efficacy of combined ICBs by increasing effector memory CD8+ T cells, inducing effector NK cells in the spleen and reducing tumor infiltrating regulatory T cells and myeloid derived suppressor cells (MDSC), in the tumor microenvironment (TME). Guadecitabine in association with ICBs increased serum levels of IFN-γ and IFN-γ-induced chemokines with anti-angiogenic activity. Guadecitabine led to a general DNA-demethylation, in particular of sites of intermediate methylation levels. CONCLUSIONS: These results indicate Guadecitabine as a promising epigenetic drug to be added to ICBs therapy.


Assuntos
Melanoma , Células Supressoras Mieloides , Animais , Camundongos , Antígeno CTLA-4 , Melanoma/patologia , Linfócitos T Reguladores , Células Matadoras Naturais/patologia , Microambiente Tumoral
15.
Lab Invest ; 92(3): 458-65, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22157715

RESUMO

Epigenetic alterations are hallmarks of cancer and powerful biomarkers, whose clinical utilization is made difficult by the absence of standardization and of common methods of data interpretation. The coordinate methylation of many loci in cancer is defined as 'CpG island methylator phenotype' (CIMP) and identifies clinically distinct groups of patients. In neuroblastoma (NB), CIMP is defined by a methylation signature, which includes different loci, but its predictive power on outcome is entirely recapitulated by the PCDHB cluster only. We have developed a robust and cost-effective pyrosequencing-based assay that could facilitate the clinical application of CIMP in NB. This assay permits the unbiased simultaneous amplification and sequencing of 17 out of 19 genes of the PCDHB cluster for quantitative methylation analysis, taking into account all the sequence variations. As some of these variations were at CpG doublets, we bypassed the data interpretation conducted by the methylation analysis software to assign the corrected methylation value at these sites. The final result of the assay is the mean methylation level of 17 gene fragments in the protocadherin B cluster (PCDHB) cluster. We have utilized this assay to compare the methylation levels of the PCDHB cluster between high-risk and very low-risk NB patients, confirming the predictive value of CIMP. Our results demonstrate that the pyrosequencing-based assay herein described is a powerful instrument for the analysis of this gene cluster that may simplify the data comparison between different laboratories and, in perspective, could facilitate its clinical application. Furthermore, our results demonstrate that, in principle, pyrosequencing can be efficiently utilized for the methylation analysis of gene clusters with high internal homologies.


Assuntos
Caderinas/genética , Metilação de DNA , Neuroblastoma/diagnóstico , Análise de Sequência de DNA/métodos , Criança , Pré-Escolar , Ilhas de CpG , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Família Multigênica , Neuroblastoma/genética , Fenótipo , Medição de Risco
16.
Eur J Cancer ; 170: 27-41, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35580369

RESUMO

BACKGROUND AND AIM OF THE STUDY: Mutations in the Gα-genes GNAQ and GNA11 are found in 85-90% of uveal melanomas (UM). Aim of the study is to understand whether the mutations in both genes differentially affect tumor characteristics and outcome and if so, to identify potential mechanisms. METHODS: We analyzed the association between GNAQ and GNA11 mutations with disease-specific survival, gene expression profiles, and cytogenetic alterations in 219 UMs. We used tandem-affinity-purification, mass spectrometry and immunoprecipitation to identify protein interaction partners of the two G-proteins and analyzed their impact on DNA-methylation. RESULTS: GNA11 mutation was associated with: i) an increased frequency of loss of BRCA1-associated protein 1 (BAP1) expression (p = 0.0005), ii) monosomy of chromosome 3 (p < 0.001), iii) amplification of chr8q (p = 0.038), iv) the combination of the latter two (p = 0.0002), and inversely with v) chr6p gain (p = 0.003). Our analysis also showed a shorter disease-specific survival of GNA11-mutated cases as compared to those carrying a GNAQ mutation (HR = 1.97 [95%CI 1.12-3.46], p = 0.02). GNAQ and GNA11 encoded G-proteins have different protein interaction partners. Specifically, the Tet Methylcytosine Dioxygenase 2 (TET2), a protein that is involved in DNA demethylation, physically interacts with the GNAQ protein but not with GNA11, as confirmed by immunoprecipitation analyses. High-risk UM cases show a clearly different DNA-methylation pattern, suggesting that a different regulation of DNA methylation by the two G-proteins might convey a different risk of progression. CONCLUSIONS: GNA11 mutated uveal melanoma has worse prognosis and is associated with high risk cytogenetic, mutational and molecular tumor characteristics that might be determined at least in part by differential DNA-methylation.


Assuntos
Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP , Subunidades alfa de Proteínas de Ligação ao GTP , Melanoma , Neoplasias Uveais , Aberrações Cromossômicas , Análise Mutacional de DNA , Subunidades alfa de Proteínas de Ligação ao GTP/genética , Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP/genética , Humanos , Melanoma/patologia , Mutação , Proteínas Supressoras de Tumor/genética , Ubiquitina Tiolesterase/genética , Neoplasias Uveais/genética , Neoplasias Uveais/patologia
18.
Metabolites ; 12(1)2021 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-35050128

RESUMO

Fanconi Anemia (FA) is a rare recessive genetic disorder characterized by aplastic anemia due to a defective DNA repair system. In addition, dysfunctional energy metabolism, lipid droplets accumulation, and unbalanced oxidative stress are involved in FA pathogenesis. Thus, to modulate the altered metabolism, Fanc-A lymphoblast cell lines were treated with quercetin, a flavonoid compound, C75 (4-Methylene-2-octyl-5-oxotetrahydrofuran-3-carboxylic acid), a fatty acid synthesis inhibitor, and rapamycin, an mTOR inhibitor, alone or in combination. As a control, isogenic FA cell lines corrected with the functional Fanc-A gene were used. Results showed that: (i) quercetin recovered the energy metabolism efficiency, reducing oxidative stress; (ii) C75 caused the lipid accumulation decrement and a slight oxidative stress reduction, without improving the energy metabolism; (iii) rapamycin reduced the aerobic metabolism and the oxidative stress, without increasing the energy status. In addition, all molecules reduce the accumulation of DNA double-strand breaks. Two-by-two combinations of the three drugs showed an additive effect compared with the action of the single molecule. Specifically, the quercetin/C75 combination appeared the most efficient in the mitochondrial and lipid metabolism improvement and in oxidative stress production reduction, while the quercetin/rapamycin combination seemed the most efficient in the DNA breaks decrement. Thus, data reported herein suggest that FA is a complex and multifactorial disease, and a multidrug strategy is necessary to correct the metabolic alterations.

19.
J Cancer Res Clin Oncol ; 147(2): 459-468, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33216211

RESUMO

PURPOSE: Programmed death-ligand 1 (PD-L1) protein plays a central role in the antitumor immune response, and appears to be a predictor of prognosis and efficacy for PD-L1 and programmed death 1 (PD-1) blockade therapy. The immunoregulatory role and prognostic impact of PD-L1 soluble form (sPD-L1) have been investigated in biological fluids of patients with different tumors. In malignant pleural mesothelioma (MPM), circulating sPD-L1 has been recently reported in patients' sera, but no data are available in pleural effusions (PE). In our study, we evaluated the baseline expression levels of sPD-L1 in PE from 84 MPM patients and correlated them with PD-L1-status in matched tumors and patients' overall survival (OS). METHODS: sPD-L1 in PE was determined by ELISA and tumor PD-L1 by immunohistochemistry. Association of sPD-L1 with OS was estimated using the Cox regression model. RESULTS: We observed that sPD-L1 was variably expressed in all the PE and tended to be higher (by 30%) in patients with PD-L1-positive tumors (cut-off ≥ 1% stained cells) as compared to patients with PD-L1-negative tumors (geometric mean ratio = 1.28, P value = 0.288). sPD-L1 levels were significantly higher than those of sPD-1 (P value = 0.001) regardless of the MPM histotypes and they were positively correlated (r = 0.50, P value < 0.001). Moreover, high PE sPD-L1 concentrations were associated with a trend towards increased OS (hazard ratio 0.79, 95% CL 0.62-1.01, P value = 0.062). CONCLUSIONS: Our study documents the presence of sPD-L1 in PE of MPM patients, and suggests its possible biological and prognostic role in MPM.


Assuntos
Antígeno B7-H1/fisiologia , Mesotelioma Maligno/imunologia , Derrame Pleural/metabolismo , Idoso , Idoso de 80 Anos ou mais , Antígeno B7-H1/análise , Feminino , Humanos , Imuno-Histoquímica , Masculino , Mesotelioma Maligno/mortalidade , Pessoa de Meia-Idade , Prognóstico , Receptor de Morte Celular Programada 1/análise , Modelos de Riscos Proporcionais
20.
Int J Cancer ; 126(3): 656-68, 2010 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-19626586

RESUMO

The aim of our study was to identify threshold levels of DNA methylation predictive of the outcome to better define the risk group of stage 4 neuroblastic tumor patients. Quantitative pyrosequencing analysis was applied to a training set of 50 stage 4, high risk patients and to a validation cohort of 72 consecutive patients. Stage 4 patients at lower risk and ganglioneuroma patients were included as control groups. Predictive thresholds of methylation were identified by ROC curve analysis. The prognostic end points of the study were the overall and progression-free survival at 60 months. Data were analyzed with the Cox proportional hazard model. In a multivariate model the methylation threshold identified for the SFN gene (14.3.3sigma) distinguished the patients presenting favorable outcome from those with progressing disease, independently from all known predictors (Training set: Overall Survival HR 8.53, p = 0.001; Validation set: HR 4.07, p = 0.008). The level of methylation in the tumors of high-risk patients surviving more than 60 months was comparable to that of tumors derived from lower risk patients and to that of benign ganglioneuroma. Methylation above the threshold level was associated with reduced SFN expression in comparison with samples below the threshold. Quantitative methylation is a promising tool to predict survival in neuroblastic tumor patients. Our results lead to the hypothesis that a subset of patients considered at high risk-but displaying low levels of methylation-could be assigned at a lower risk group.


Assuntos
Biomarcadores Tumorais/genética , Metilação de DNA , Exonucleases/genética , Ganglioneuroblastoma/genética , Ganglioneuroma/genética , Proteínas de Neoplasias/genética , Neuroblastoma/genética , Neoplasias de Tecidos Moles/genética , Proteínas 14-3-3 , Azacitidina/farmacologia , Biomarcadores Tumorais/biossíntese , Linhagem Celular Tumoral/efeitos dos fármacos , Linhagem Celular Tumoral/metabolismo , Criança , Pré-Escolar , Estudos de Coortes , Ilhas de CpG , Metilação de DNA/efeitos dos fármacos , DNA de Neoplasias/química , DNA de Neoplasias/genética , Exonucleases/biossíntese , Exorribonucleases , Feminino , Ganglioneuroblastoma/mortalidade , Ganglioneuroblastoma/patologia , Ganglioneuroma/mortalidade , Ganglioneuroma/patologia , Humanos , Lactente , Estimativa de Kaplan-Meier , Masculino , Proteínas de Neoplasias/biossíntese , Neuroblastoma/mortalidade , Neuroblastoma/patologia , Prognóstico , Modelos de Riscos Proporcionais , Risco , Medição de Risco , Análise de Sequência de DNA , Neoplasias de Tecidos Moles/mortalidade , Neoplasias de Tecidos Moles/patologia , Sobreviventes/estatística & dados numéricos
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