Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 6 de 6
Filtrar
Mais filtros








Base de dados
Intervalo de ano de publicação
1.
Cell Rep ; 42(4): 112303, 2023 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-36952341

RESUMO

Oncogenes destabilize STING in epithelial cell-derived cancer cells, such as head and neck squamous cell carcinomas (HNSCCs), to promote immune escape. Despite the abundance of tumor-infiltrating myeloid cells, HNSCC presents notable resistance to STING stimulation. Here, we show how saturated fatty acids in the microenvironment dampen tumor response to STING stimulation. Using single-cell analysis, we found that obesity creates an IFN-I-deprived tumor microenvironment with a massive expansion of suppressive myeloid cell clusters and contraction of effector T cells. Saturated fatty acids, but not unsaturated fatty acids, potently inhibit the STING-IFN-I pathway in HNSCC cells. Myeloid cells from obese mice show dampened responses to STING stimulation and are more suppressive of T cell activation. In agreement, obese hosts exhibited increased tumor burden and lower responsiveness to STING agonist. As a mechanism, saturated fatty acids induce the expression of NLRC3, depletion of which results in a T cell inflamed tumor microenvironment and IFN-I-dependent tumor control.


Assuntos
Neoplasias de Cabeça e Pescoço , Interferon Tipo I , Camundongos , Animais , Carcinoma de Células Escamosas de Cabeça e Pescoço , Ácidos Graxos , Interferon Tipo I/metabolismo , Células Mieloides/metabolismo , Microambiente Tumoral
2.
Oncoimmunology ; 10(1): 1997385, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34858725

RESUMO

Type-I interferon (IFN-I) signaling is critical to maintaining antigen-presenting cell function for anti-tumor immunity. However, recent studies have suggested that IFN-I signaling may also contribute to more aggressive phenotypes, raising the possibility that IFN-I downstream signaling in cancer and myeloid cells may exert dichotomous functions.We analyzed the clinicopathologic correlation of cancer-specific IFN-I activation in 195 head and neck squamous cell carcinoma patients. We also characterized the immune impact of IFN-I receptor (IFNAR1)-deficiency in syngeneic tumor models using biochemistry, flow cytometry, and single-cell RNA-Seq. We stained HNSCC tissue microarrays with a sensitive IFN-I downstream signaling activation marker, MX1, and quantitated cancer cell-specific MX1 staining. Kaplan-Meier analysis revealed that MX1-high tumors exhibited worse survival, a phenotype that depends on the number of CD8+ intratumoral T-cells. We found that cancer-specific IFNAR1 engagement promotes cancer stemness and higher expression levels of suppressive immune checkpoint receptor ligands in cancer-derived exosomes. Notably, mice bearing Ifnar1-deficient tumors exhibited lower tumor burden, increased T-cell infiltration, reduced exhausted CD4+PD1high T-cells, and increased effector population CD8+IFN-γ+ T-cells. Then, we performed single-cell RNA-sequencing and discovered that cancer-specific IFN-I signaling not only restricts effector cells expansion but also dampens their functional fitness.The beneficial role of IFN-I activation is largely dependent on the myeloid compartment. Cancer-specific IFN-I receptor engagement promotes cancer stemness and the release of cancer-derived exosomes with high expression levels of immune checkpoint receptor ligands. Cancer-specific IFN-I activation is associated with poor immunogenicity and worse clinical outcomes in HNSCC.


Assuntos
Linfócitos T CD8-Positivos , Neoplasias de Cabeça e Pescoço , Animais , Humanos , Camundongos , Transdução de Sinais , Carcinoma de Células Escamosas de Cabeça e Pescoço
3.
Lab Chip ; 20(3): 634-646, 2020 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-31922156

RESUMO

The human-derived orthotopic xenograft mouse model is an effective platform for performing in vivo bladder cancer studies to examine tumor development, metastasis, and therapeutic effects of drugs. To date, the surveillance of tumor progression in real time for orthotopic bladder xenografts is highly dependent on semi-quantitative in vivo imaging technologies such as bioluminescence. While these imaging technologies can estimate tumor progression, they are burdened with requirements such as anesthetics, specialized equipment, and genetic modification of the injected cell line. Thus, a convenient and non-invasive technology to quantitatively monitor the growth of bladder cancer in orthotopic xenografts is highly desired. In this work, using a microfluidic chemiluminescent ELISA platform, we have successfully developed a rapid, multiparameter urine-based and non-invasive biomolecular prognostic technology for orthotopic bladder cancer xenografts. This method consists of two steps. First, the concentrations of a panel of four urinary biomarkers are quantified from the urine of mice bearing orthotopic bladder xenografts. Second, machine learning and principal component analysis (PCA) algorithms are applied to analyze the urinary biomarkers, and subsequently, a score is assigned to indicate the tumor growth. With this methodology, we have quantitatively monitored the orthotopic growth of human bladder cancer that was inoculated with low, medium, and high cancer cell numbers. We also employed this method and performed a proof of principle experiment to examine the in vivo therapeutic efficacy of the EGFR inhibitor, dacomitinib.


Assuntos
Neoplasias da Bexiga Urinária/urina , Animais , Linhagem Celular Tumoral , Ensaio de Imunoadsorção Enzimática , Humanos , Dispositivos Lab-On-A-Chip , Medições Luminescentes , Camundongos , Vigilância da População , Neoplasias da Bexiga Urinária/diagnóstico por imagem
4.
Nat Protoc ; 14(3): 738-755, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30683938

RESUMO

The invasion of bladder cancer into the sub-urothelial muscle and vasculature are key determinants leading to lethal metastatic progression. However, the molecular basis is poorly understood, partly because of the lack of uncomplicated and reliable models that recapitulate the biology of locally invasive disease. We developed a surgical grafting technique, characterized by a simple, rapid, reproducible and high-efficiency approach, to recapitulate the pathobiological events of human bladder cancer invasion in mice. This technique consists of a small laparotomy and direct implantation of human cancer cells into the bladder lumen. Unlike other protocols, it does not require debriding of the urothelial lining, injection into the bladder wall, specialized imaging equipment, bladder catheterization or costly surgical equipment. With minimal practice, the procedure can be executed in <10 min. Tumors develop with a high take rate, and most cell lines exhibit local invasion within 4 weeks of implantation.


Assuntos
Progressão da Doença , Neoplasias da Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/cirurgia , Ensaios Antitumorais Modelo de Xenoenxerto/métodos , Animais , Modelos Animais de Doenças , Humanos , Camundongos Endogâmicos NOD , Camundongos SCID , Invasividade Neoplásica
5.
Bladder Cancer ; 4(1): 77-90, 2018 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-29430509

RESUMO

BACKGROUND: The HER family of proteins (EGFR, HER2, HER3 and HER4) have long been thought to be therapeutic targets for bladder cancer, but previous clinical trials targeting these proteins have been disappointing. Second generation agents may be more effective. OBJECTIVE: The aim of this study was to evaluate responses to two second-generation irreversible tyrosine kinase inhibitors, dacomitinib and afatinib, in bladder cancer cell lines. METHODS: Cell lines were characterized by targeted next generation DNA sequencing, RNA sequencing, western blotting and flow cytometry. Cell survival responses to dacomitinib or afatinib were determined using (3-[4,5-dimethylthioazol-2-yl]-2,5-diphenyl tetrazolium bromide) (MTT) or [3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) and phenazine methosylfate (PMS) cell survival assays. RESULTS: Only two cell lines of 12 tested were sensitive to afatinib. Sensitivity to afatinib was significantly associated with mutation in either HER2 or HER3 (p < 0.05). The two cell lines sensitive to afatinib were also responsive to dacomitinib ralong with an additional 4 other cell lines out of 16 tested. No characteristic was associated with dacomitinib sensitivity. Molecular profiling demonstrated that only two genes were high in both afatinib and dacomitinib sensitive cells. Further rhigher expression of RAS pathway genes was noted for dacomitinib responsive cells. CONCLUSIONS: This study confirms that cell line screening can be useful in pre-clinical evaluation of targeted small molecule inhibitors and suggests that compounds with similar structure(s) and target(s) may have distinct sensitivity profiles. Further rcombinational targeting of additional molecularly relevant pathways may be important in enhancing responses to HER targeted agents in bladder cancer.

6.
Cancer Res ; 77(1): 74-85, 2017 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-27793843

RESUMO

Activation of the EGF receptors EGFR (ErbB1) and HER2 (ErbB2) drives the progression of multiple cancer types through complex mechanisms that are still not fully understood. In this study, we report that HER2 expression is elevated in bone metastases of prostate cancer independently of gene amplification. An examination of HER2 and NF-κB receptor (RANK) coexpression revealed increased levels of both proteins in aggressive prostate tumors and metastatic deposits. Inhibiting HER2 expression in bone tumor xenografts reduced proliferation and RANK expression while maintaining EGFR expression. In examining the role of EGFR in tumor-initiating cells (TIC), we found that EGFR expression was required for primary and secondary sphere formation of prostate cancer cells. EGFR expression was also observed in circulating tumor cells (CTC) during prostate cancer metastasis. Dual inhibition of HER2 and EGFR resulted in significant inhibition of tumor xenograft growth, further supporting the significance of these receptors in prostate cancer progression. Overall, our results indicate that EGFR promotes survival of prostate TIC and CTC that metastasize to bone, whereas HER2 supports the growth of prostate cancer cells once they are established at metastatic sites. Cancer Res; 77(1); 74-85. ©2016 AACR.


Assuntos
Receptores ErbB/biossíntese , Invasividade Neoplásica/patologia , Neoplasias da Próstata/patologia , Receptor ErbB-2/biossíntese , Animais , Western Blotting , Neoplasias Ósseas/secundário , Linhagem Celular Tumoral , Progressão da Doença , Citometria de Fluxo , Xenoenxertos , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Células Neoplásicas Circulantes/patologia , Células-Tronco Neoplásicas/patologia , Análise Serial de Tecidos , Regulação para Cima
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA