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1.
Am J Hum Genet ; 108(9): 1611-1630, 2021 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-34343493

RESUMO

Genome-wide association studies (GWASs) have identified a melanoma-associated locus on chromosome band 7p21.1 with rs117132860 as the lead SNP and a secondary independent signal marked by rs73069846. rs117132860 is also associated with tanning ability and cutaneous squamous cell carcinoma (cSCC). Because ultraviolet radiation (UVR) is a key environmental exposure for all three traits, we investigated the mechanisms by which this locus contributes to melanoma risk, focusing on cellular response to UVR. Fine-mapping of melanoma GWASs identified four independent sets of candidate causal variants. A GWAS region-focused Capture-C study of primary melanocytes identified physical interactions between two causal sets and the promoter of the aryl hydrocarbon receptor (AHR). Subsequent chromatin state annotation, eQTL, and luciferase assays identified rs117132860 as a functional variant and reinforced AHR as a likely causal gene. Because AHR plays critical roles in cellular response to dioxin and UVR, we explored links between this SNP and AHR expression after both 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and ultraviolet B (UVB) exposure. Allele-specific AHR binding to rs117132860-G was enhanced following both, consistent with predicted weakened AHR binding to the risk/poor-tanning rs117132860-A allele, and allele-preferential AHR expression driven from the protective rs117132860-G allele was observed following UVB exposure. Small deletions surrounding rs117132860 introduced via CRISPR abrogates AHR binding, reduces melanocyte cell growth, and prolongs growth arrest following UVB exposure. These data suggest AHR is a melanoma susceptibility gene at the 7p21.1 risk locus and rs117132860 is a functional variant within a UVB-responsive element, leading to allelic AHR expression and altering melanocyte growth phenotypes upon exposure.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Carcinoma de Células Escamosas/genética , Cromossomos Humanos Par 7 , Loci Gênicos , Melanócitos/metabolismo , Melanoma/genética , Receptores de Hidrocarboneto Arílico/genética , Neoplasias Cutâneas/genética , Alelos , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Carcinogênese/genética , Carcinogênese/metabolismo , Carcinogênese/patologia , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Cromatina/química , Cromatina/metabolismo , Regulação da Expressão Gênica , Predisposição Genética para Doença , Genoma Humano , Estudo de Associação Genômica Ampla , Humanos , Melanócitos/efeitos dos fármacos , Melanócitos/patologia , Melanócitos/efeitos da radiação , Melanoma/metabolismo , Melanoma/patologia , Dibenzodioxinas Policloradas/toxicidade , Polimorfismo de Nucleotídeo Único , Cultura Primária de Células , Regiões Promotoras Genéticas , Receptores de Hidrocarboneto Arílico/metabolismo , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia , Banho de Sol , Raios Ultravioleta/efeitos adversos
2.
Nat Commun ; 12(1): 4031, 2021 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-34188042

RESUMO

The response of patients with recurrent glioblastoma multiforme to neoadjuvant immune checkpoint blockade has been challenging to interpret due to the inter-patient and intra-tumor heterogeneity. We report on a comparative analysis of tumor tissues collected from patients with recurrent glioblastoma and high-risk melanoma, both treated with neoadjuvant checkpoint blockade. We develop a framework that uses multiplex spatial protein profiling, machine learning-based image analysis, and data-driven computational models to investigate the pathophysiological and molecular factors within the tumor microenvironment that influence treatment response. Using melanoma to guide the interpretation of glioblastoma analyses, we interrogate the protein expression in microscopic compartments of tumors, and determine the correlates of cytotoxic CD8+ T cells, tumor growth, treatment response, and immune cell-cell interaction. This work reveals similarities shared between glioblastoma and melanoma, immunosuppressive factors that are unique to the glioblastoma microenvironment, and potential co-targets for enhancing the efficacy of neoadjuvant immune checkpoint blockade.


Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Antígeno CTLA-4/antagonistas & inibidores , Glioblastoma/tratamento farmacológico , Inibidores de Checkpoint Imunológico/uso terapêutico , Melanoma/tratamento farmacológico , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Adulto , Idoso , Antineoplásicos Imunológicos/uso terapêutico , Biomarcadores Tumorais/análise , Neoplasias Encefálicas/patologia , Linfócitos T CD8-Positivos/imunologia , Feminino , Glioblastoma/patologia , Humanos , Ipilimumab/uso terapêutico , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/patologia , Nivolumabe/uso terapêutico , Resultado do Tratamento , Microambiente Tumoral/imunologia
3.
Nat Commun ; 12(1): 346, 2021 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-33436641

RESUMO

Anti-PD-1 therapy is used as a front-line treatment for many cancers, but mechanistic insight into this therapy resistance is still lacking. Here we generate a humanized (Hu)-mouse melanoma model by injecting fetal liver-derived CD34+ cells and implanting autologous thymus in immune-deficient NOD-scid IL2Rγnull (NSG) mice. Reconstituted Hu-mice are challenged with HLA-matched melanomas and treated with anti-PD-1, which results in restricted tumor growth but not complete regression. Tumor RNA-seq, multiplexed imaging and immunohistology staining show high expression of chemokines, as well as recruitment of FOXP3+ Treg and mast cells, in selective tumor regions. Reduced HLA-class I expression and CD8+/Granz B+ T cells homeostasis are observed in tumor regions where FOXP3+ Treg and mast cells co-localize, with such features associated with resistance to anti-PD-1 treatment. Combining anti-PD-1 with sunitinib or imatinib results in the depletion of mast cells and complete regression of tumors. Our results thus implicate mast cell depletion for improving the efficacy of anti-PD-1 therapy.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Linfócitos do Interstício Tumoral/imunologia , Mastócitos/imunologia , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Animais , Linfócitos B/efeitos dos fármacos , Linfócitos B/imunologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Humanos , Inibidores de Checkpoint Imunológico/farmacologia , Linfócitos do Interstício Tumoral/efeitos dos fármacos , Mastócitos/efeitos dos fármacos , Melanoma/imunologia , Melanoma/patologia , Melanoma/terapia , Camundongos Transgênicos , Receptor de Morte Celular Programada 1/metabolismo , Sunitinibe/farmacologia , Sunitinibe/uso terapêutico , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia
4.
Environ Toxicol ; 35(11): 1225-1233, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32697429

RESUMO

Hepatocellular carcinoma is the second leading cause of cancer-related mortality worldwide. Lagerstroemia speciosa Pers. (Lythraceae) commonly known as Banaba has been used in different forms in traditional medicinal systems for treating various diseases which include diabetes and obesity. In this study, we investigated the cytotoxic potential of ethanolic Banaba leaf extract (EBLE) in HepG2 cells. The phytochemical analysis of EBLE was performed by HPTLC. HepG2 cells were treated with EBLE at 25, 50, 100, and 150 µg/mL concentrations, and cytotoxicity was evaluated by MTT assay. Oxidative stress was assessed by the evaluation of lipid peroxidation, superoxide dismutase, and reduced glutathione. Apoptosis-related morphology was investigated by acridine orange and ethidium bromide (AO/EB) dual staining. Mitochondrial membrane potential (ΔΨm) was evaluated by JC-1 staining. Apoptosis-related marker genes were evaluated by qPCR. HPTLC analysis confirmed the presence of corosolic acid (12.87 µg/mg), berberine (3.19 µg/mg), and gallic acid (2.94 µg/mg) in EBLE. EBLE treatments caused significant and concentration-dependent cytotoxicity and oxidative stress in HepG2 cells. Dual staining with AO/EB confirmed membrane distortion and nuclear chromatin condensation upon EBLE treatments. JC-I staining revealed the loss of ΔΨm. Furthermore, at a molecular level, EBLE treatments interfere with Bax/Bcl-2 homeostasis and induced the pro-apoptotic marker genes such as cytochrome c, Apaf-1, and caspases 9 and 3. EBLE treatments caused cytotoxicity in HepG2 cells, and this could be due to the induction of oxidative stress and apoptosis via the intrinsic or mitochondrial pathway.


Assuntos
Antineoplásicos/toxicidade , Extratos Vegetais/toxicidade , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular/patologia , Caspase 9 , Células Hep G2 , Humanos , Lagerstroemia , Neoplasias Hepáticas/patologia , Mitocôndrias/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2 , Triterpenos
5.
Nat Commun ; 11(1): 853, 2020 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-32051401

RESUMO

Although immune checkpoint inhibitors (ICIs) have achieved unprecedented results in melanoma, the biological features of the durable responses initiated by these drugs remain unknown. Here we show the genetic and phenotypic changes induced by treatment with programmed cell death-1 (PD-1) blockade in a genetically engineered mouse model of melanoma driven by oncogenic BRAF. In this controlled system anti-PD-1 treatment yields responses in ~35% of the tumors, and prolongs survival in ~27% of the animals. We identify increased stroma remodeling and reduced expression of proliferation markers as features associated with prolonged response. These traits are corroborated in two independent early on-treatment anti-PD-1 melanoma patient cohorts. These insights into the biological responses of tumors to ICI provide a strategy for identification of durable response early during the course of treatment and could improve patient stratification for checkpoint inhibitory drugs.


Assuntos
Divisão Celular/fisiologia , Melanoma/metabolismo , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Células Estromais/metabolismo , Animais , Linfócitos T CD4-Positivos , Linfócitos T CD8-Positivos , Proliferação de Células , Modelos Animais de Doenças , Exoma/genética , Feminino , Humanos , Imunoterapia , Camundongos
6.
Nature ; 577(7791): 549-555, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31942075

RESUMO

Treatment with immune checkpoint blockade (ICB) has revolutionized cancer therapy. Until now, predictive biomarkers1-10 and strategies to augment clinical response have largely focused on the T cell compartment. However, other immune subsets may also contribute to anti-tumour immunity11-15, although these have been less well-studied in ICB treatment16. A previously conducted neoadjuvant ICB trial in patients with melanoma showed via targeted expression profiling17 that B cell signatures were enriched in the tumours of patients who respond to treatment versus non-responding patients. To build on this, here we performed bulk RNA sequencing and found that B cell markers were the most differentially expressed genes in the tumours of responders versus non-responders. Our findings were corroborated using a computational method (MCP-counter18) to estimate the immune and stromal composition in this and two other ICB-treated cohorts (patients with melanoma and renal cell carcinoma). Histological evaluation highlighted the localization of B cells within tertiary lymphoid structures. We assessed the potential functional contributions of B cells via bulk and single-cell RNA sequencing, which demonstrate clonal expansion and unique functional states of B cells in responders. Mass cytometry showed that switched memory B cells were enriched in the tumours of responders. Together, these data provide insights into the potential role of B cells and tertiary lymphoid structures in the response to ICB treatment, with implications for the development of biomarkers and therapeutic targets.


Assuntos
Linfócitos B/imunologia , Carcinoma de Células Renais/tratamento farmacológico , Carcinoma de Células Renais/imunologia , Imunoterapia , Melanoma/tratamento farmacológico , Melanoma/imunologia , Estruturas Linfoides Terciárias/imunologia , Linfócitos B/citologia , Linfócitos B/metabolismo , Biomarcadores Tumorais/análise , Carcinoma de Células Renais/patologia , Carcinoma de Células Renais/cirurgia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/imunologia , Células Clonais/citologia , Células Clonais/imunologia , Células Clonais/metabolismo , Células Dendríticas Foliculares/citologia , Células Dendríticas Foliculares/imunologia , Regulação Neoplásica da Expressão Gênica , Humanos , Memória Imunológica/imunologia , Espectrometria de Massas , Melanoma/patologia , Melanoma/cirurgia , Metástase Neoplásica/genética , Fenótipo , Prognóstico , RNA-Seq , Receptores Imunológicos/imunologia , Análise de Célula Única , Linfócitos T/citologia , Linfócitos T/imunologia , Transcriptoma
7.
Clin Cancer Res ; 25(24): 7424-7435, 2019 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-31515461

RESUMO

PURPOSE: Previously identified transcriptomic signatures have been based on primary and metastatic melanomas with relatively few American Joint Committee on Cancer (AJCC) stage I tumors, given difficulties in sampling small tumors. The advent of adjuvant therapies has highlighted the need for better prognostic and predictive biomarkers, especially for AJCC stage I and stage II disease. EXPERIMENTAL DESIGN: A total of 687 primary melanoma transcriptomes were generated from the Leeds Melanoma Cohort (LMC). The prognostic value of existing signatures across all the AJCC stages was tested. Unsupervised clustering was performed, and the prognostic value of the resultant signature was compared with that of sentinel node biopsy (SNB) and tested as a biomarker in three published immunotherapy datasets. RESULTS: Previous Lund and The Cancer Genome Atlas signatures predicted outcome in the LMC dataset (P = 10-8 to 10-4) but showed a significant interaction with AJCC stage (P = 0.04) and did not predict outcome in stage I tumors (P = 0.3-0.7). Consensus-based classification of the LMC dataset identified six classes that predicted outcome, notably in stage I disease. LMC class was a similar indicator of prognosis when compared with SNB, and it added prognostic value to the genes reported by Gerami and colleagues. One particular LMC class consistently predicted poor outcome in patients receiving immunotherapy in two of three tested datasets. Biological characterization of this class revealed high JUN and AXL expression and evidence of epithelial-to-mesenchymal transition. CONCLUSIONS: A transcriptomic signature of primary melanoma was identified with prognostic value, including in stage I melanoma and in patients undergoing immunotherapy.


Assuntos
Biomarcadores Tumorais/genética , Biologia Computacional/métodos , Regulação Neoplásica da Expressão Gênica , Imunoterapia/mortalidade , Melanoma/patologia , Neoplasias Cutâneas/patologia , Transcriptoma , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Humanos , Masculino , Melanoma/genética , Melanoma/terapia , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/terapia , Taxa de Sobrevida , Resultado do Tratamento , Adulto Jovem
8.
Colloids Surf B Biointerfaces ; 120: 110-7, 2014 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-24905685

RESUMO

Resveratrol, a dietary non-flavonoid polyphenolic phytoalexin, has gained attention in cancer chemoprevention. However, poor aqueous solubility and cellular bioavailability has limited its therapeutic application. We formulated a lipid based delivery system of resveratrol with self nanoemulsifying ability. Several edible and safe lipids, surfactants and cosolvents were screened for solubilization of resevratrol. Developed formulation comprised of Acrysol K 150 as a lipid and mixture of Labrasol and Transcutol HP as the surfactant system, as these components showed higher solubility. Pseudoternary phase diagram was constructed to identify the region of nanoemulsification. The formulations showed rapid emulsification with an average globule diameter; 85nm to 120nm and slight negative zeta potential. The nanocompositions exhibited cloud point above 55°C and were stable toward the gastrointestinal pH and thermodynamic stress testing. As compared to pristine resveratrol, the developed delivery system showed significant increase in vitro cytotoxicity in MCF-7 breast cancer cells. In vivo chick chorioallantoic membrane assay revealed enhanced antiangiogenic activity of composition with high lipid level. Briefly, lipid based nanoemulsifying resveratrol dramatically enhanced the anticancer and antiangiogenic activities, thus increasing its potential application in cancer chemotherapy.


Assuntos
Inibidores da Angiogênese/farmacologia , Fenômenos Químicos/efeitos dos fármacos , Lipídeos/química , Estilbenos/farmacologia , Compostos de Alumínio/química , Animais , Antineoplásicos/farmacologia , Morte Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Galinhas , Membrana Corioalantoide/efeitos dos fármacos , Sistemas de Liberação de Medicamentos , Emulsões , Etilenoglicóis/química , Glicerídeos , Humanos , Concentração de Íons de Hidrogênio , Células MCF-7 , Compostos de Magnésio/química , Compostos Orgânicos/química , Tamanho da Partícula , Transição de Fase/efeitos dos fármacos , Resveratrol , Silicatos/química , Solubilidade , Eletricidade Estática , Termodinâmica
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