RESUMO
Altered metabolic pathways in cancer such as exacerbated glycolytic flux and increased glutamine metabolism are promising targets for anti-cancer therapies. While commonly observed in glycolytic tumors, extracellular acidosis has never been considered as a potential modulator of anti-metabolic drug activity such as dichloroacetate (DCA). Using cancer cells from various origins selected for their ability to proliferate under acidic conditions, we found that DCA exerts greater inhibitory effects on the growth of these acid-adapted cells than in parental cells. Moreover, daily DCA administration to mice led to a significant decrease in tumor growth from acid-adapted cells but not from parental cells. 13C-tracer studies revealed that DCA induced a double metabolic shift, diminishing glycolysis and increasing intracellular glutamine in acid-adapted cells. As a consequence, DCA reduced the pentose phosphate pathway activity more extensively and increased apoptosis in acid-adapted cells. Finally, the combination of DCA with a glutaminase inhibitor significantly enhanced the cytotoxic effects of DCA. Overall, the interplay between acidosis and DCA exposure leads to metabolic reprogramming that considerably alters cellular fitness.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Ácido Dicloroacético/farmacologia , Neoplasias/tratamento farmacológico , Sulfetos/farmacologia , Tiadiazóis/farmacologia , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ácido Dicloroacético/uso terapêutico , Sinergismo Farmacológico , Feminino , Glutaminase/antagonistas & inibidores , Glutaminase/metabolismo , Glutamina/metabolismo , Glicólise/efeitos dos fármacos , Humanos , Concentração de Íons de Hidrogênio , Camundongos , Neoplasias/patologia , Via de Pentose Fosfato/efeitos dos fármacos , Piruvato Desidrogenase Quinase de Transferência de Acetil/antagonistas & inibidores , Piruvato Desidrogenase Quinase de Transferência de Acetil/metabolismo , Sulfetos/uso terapêutico , Tiadiazóis/uso terapêutico , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
BACKGROUND: BRAF inhibitors (BRAFi) improve survival in metastatic melanoma patients (MMP) but the duration of clinical benefit is limited by development of drug resistance. Here, we investigated whether the expression of programmed death-ligand 1 (PD-L1) and the density of tumor-infiltrating mononuclear cells (TIMC) predict the occurrence of resistance, hence affecting the clinical outcome in BRAFi-treated MMP. METHODS: PD-L1 expression (cutoff 5%) was analyzed by immunohistochemistry with two different antibodies in BRAF(V600)-mutated formalin-fixed and paraffin-embedded samples from 80 consecutive MMP treated with BRAFi at a single institution. TIMC were evaluated by conventional hematoxylin and eosin staining. RESULTS: Forty-six and 34 patients received vemurafenib and dabrafenib, respectively. Membranous expression of PD-L1 was detected in 28/80 (35%) of patients. At multivariate analysis, absence of tumoral PD-L1 staining [odd ratio (OR) 10.8, 95% confidence interval (CI) 2.7-43.3, P < 0.001] and the presence of TIMC (OR 6.5, 95% CI 1.7-24.3, P < 0.005) were associated with a better response to treatment. Median progression-free survival (PFS) and overall survival were 10 and 15 months, respectively. By multivariate assessment, PD-L1 expression [hazard ratio (HR) 4.3, 95% CI 2.1-8.7, P < 0.0001] and absence of TIMC (HR 2.5, 95% CI 1.4-4.7, P < 0.002) correlated with shorter PFS. PD-L1 overexpression (HR 6.2, 95% CI 2.8-14.2, P < 0.0001) and absence of TIMC (HR 3.1, 95% CI 1.5-6.5, P < 0.002) were independent prognostic factors for melanoma-specific survival. CONCLUSION: Our results provide the first proof-of-principle evidence for the predictive and prognostic relevance of PD-L1 immunohistochemical expression and density of immune cell infiltration in BRAF(V600)-mutated MMP treated with BRAFi.
Assuntos
Antígeno B7-H1/biossíntese , Linfócitos do Interstício Tumoral/imunologia , Melanoma/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/metabolismo , Intervalo Livre de Doença , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Humanos , Imidazóis/uso terapêutico , Indóis/uso terapêutico , Contagem de Linfócitos , Masculino , Melanoma/genética , Melanoma/mortalidade , Pessoa de Meia-Idade , Oximas/uso terapêutico , Proteínas Proto-Oncogênicas B-raf/genética , Estudos Retrospectivos , Sulfonamidas/uso terapêutico , Vemurafenib , Adulto JovemAssuntos
Fatores de Transcrição Kruppel-Like/genética , Linfoma de Zona Marginal Tipo Células B/genética , Mutação , Neoplasias Esplênicas/genética , Alelos , Transformação Celular Neoplásica , Análise Mutacional de DNA , Deleção de Genes , Dosagem de Genes , Células HEK293 , Humanos , Hibridização in Situ Fluorescente , Células Jurkat , Polimorfismo de Nucleotídeo ÚnicoRESUMO
BACKGROUND: Programmed cell death ligand 1 (PD-L1) is a cell surface molecule that plays a critical role in suppressing immune responses, mainly through binding of the PD-1 receptor on T lymphocytes. PD-L1 may be expressed by metastatic melanoma (MM). However, its clinical and biological significance remains unclear. Here, we investigated whether expression of PD-L1 in MM identifies a biologically more aggressive form of the disease, carrying prognostic relevance. PATIENTS AND METHODS: PD-L1 expression was analyzed by immunohistochemistry using two different antibodies in primary tumors and paired metastases from 81 melanoma patients treated at a single institution. Protein expression levels were correlated with PD-L1 mRNA, BRAF mutational status and clinical outcome. PD-L1(+) and PD-L1(-) subsets of the A375 cell line were stabilized in vitro and compared using gene expression profiling and functional assays. Results were confirmed using xenograft models. RESULTS: PD-L1 membrane positivity was detected in 30/81 (37%) of patients. By multivariate analysis, Breslow thickness and PD-L1 membrane positivity were independent risk factors for melanoma-specific death {PD-L1 5% cutoff [hazard ratio (HR) 3.92, confidence interval (CI) 95% 1.61-9.55 P < 0.003], PD-L1 as continuous variable (HR 1.03, 95% CI 1.02-1.04 P < 0.002)}. PD-L1 expression defined a subset of the BRAF-mutated A375 cell line characterized by a highly invasive phenotype and by enhanced ability to grow in xenograft models. CONCLUSIONS: PD-L1 is an independent prognostic marker in melanoma. If confirmed, our clinical and experimental data suggest that PD-L1(+) melanomas should be considered a disease subset with distinct genetic and morpho-phenotypic features, leading to enhanced aggressiveness and invasiveness.
Assuntos
Antígeno B7-H1/metabolismo , Biomarcadores Tumorais/metabolismo , Melanoma/metabolismo , Humanos , Melanoma/genética , Melanoma/patologia , Invasividade Neoplásica , Metástase Neoplásica , Análise de SobrevidaRESUMO
Vaccination with tumor-loaded dendritic cells (DC) is a promising treatment strategy for patients with renal cell carcinoma (RCC). Cells undergoing cell death proved useful as a source of tumor antigen for DC loading. Both apoptotic and necrotic tumor cells have been shown to efficiently load RCC-tumor antigens on DC. However, no direct comparison of these two kinds of death has been attempted in the same RCC. We compared DC pulsed with apoptotic cells, whole cell lysates or their supernatants of the cell line K1, derived from a patient with clear cell RCC, to determine their ability to activate T cells. Monocyte-derived DCs were pulsed with the different sources of tumor antigen, matured and co-cultured with autologouos peripheral blood lymphocytes. After three weekly re-stimulations with DCs, generation of cytotoxic T lymphocytes CTL was assessed by IFN-gamma release in an ELISpot assay in the presence of the sensitizing target. By comparison with lysate, apoptotic tumor cells induced a higher frequency of MHC class I-restricted IFN-gamma releasing lymphocytes. A higher CTL response was induced by pulsing DCs with cell lysate supernatant compared with whole cell lysate. These results indicate that, although necrotic death has been regarded as highly permissive when compared to apoptotic death, the immunogenicity of the death treatment may vary from one tumor to another.
Assuntos
Células Apresentadoras de Antígenos/fisiologia , Apoptose/fisiologia , Carcinoma de Células Renais/imunologia , Carcinoma de Células Renais/patologia , Neoplasias Renais/imunologia , Neoplasias Renais/patologia , Anticorpos Monoclonais/farmacologia , Antígenos de Neoplasias/farmacologia , Linhagem Celular Tumoral , Membrana Celular/efeitos dos fármacos , Membrana Celular/patologia , Proliferação de Células/efeitos dos fármacos , Técnicas de Cocultura , Citocinas/farmacologia , Células Dendríticas/efeitos dos fármacos , Ensaio de Imunoadsorção Enzimática , Humanos , Interferon gama/biossíntese , Teste de Cultura Mista de Linfócitos , Necrose , Fenótipo , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Linfócitos T/metabolismoRESUMO
Eight children with human immunodeficiency virus (HIV) and recurrent bacterial pulmonary infections were treated using a Positive Expiratory Pressure (PEP)-mask twice a day for 12 months. At the end of the study, a reduction in the number of pulmonary infections [mean (SD) 2.1 (0.9) vs 4.5 (1) p < 0.0001] and antibiotic courses [mean (SD) 1.5 (0.7) vs 2.4 (0.9) p < 0.021] was noted. The PEP-mask is a chest physiotherapy technique for removing infected secretions and optimizing airway functions that is also useful in HIV-infected children.