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1.
Cell Cycle ; 23(1): 43-55, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38263737

RESUMO

Sunitinib resistance creates a major clinical challenge for the treatment of advanced clear cell renal cell carcinoma (ccRCC) and functional and metabolic changes linked to sunitinib resistance are not fully understood. We sought to characterize the molecular and metabolic changes induced by the development of sunitinib resistance in ccRCC by developing and characterizing two human ccRCC cell lines resistant to sunitinib. Consistent with the literature, sunitinib-resistant ccRCC cell lines presented an aberrant overexpression of Axl and PD-L1, as well as a metabolic rewiring characterized by enhanced OXPHOS and glutamine metabolism. Therapeutic challenges of sunitinib-resistant ccRCC cell lines in vitro using small molecule inhibitors targeting Axl, AMPK and p38, as well as using PD-L1 blocking therapeutic antibodies, showed limited CTL-mediated cytotoxicity in a co-culture model. However, the AMPK activator metformin appears to sensitize the effect of PD-L1 blocking therapeutic antibodies and to enhance CTLs' cytotoxic effects on ccRCC cells. These effects were not broadly observed with the Axl and the p38 inhibitors. Taken together, these data suggest that targeting certain pathways aberrantly activated by sunitinib resistance such as the AMPK/PDL1 axis might sensitize ccRCC to immunotherapies as a second-line therapeutic approach.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Humanos , Sunitinibe/farmacologia , Sunitinibe/uso terapêutico , Carcinoma de Células Renais/patologia , Antígeno B7-H1 , Neoplasias Renais/patologia , Proteínas Quinases Ativadas por AMP , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos
2.
Life (Basel) ; 13(5)2023 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-37240841

RESUMO

Opioids are commonly prescribed for extended periods of time to patients with advanced clear cell renal cell carcinoma to assist with pain management. Because extended opioid exposure has been shown to affect the vasculature and to be immunosuppressive, we investigated how it may affect the metabolism and physiology of clear cell renal cell carcinoma. RNA sequencing of a limited number of archived patients' specimens with extended opioid exposure or non-opioid exposure was performed. Immune infiltration and changes in the microenvironment were evaluated using CIBERSORT. A significant decrease in M1 macrophages and T cells CD4 memory resting immune subsets was observed in opioid-exposed tumors, whereas the changes observed in other immune cells were not statistically significant. Further RNA sequencing data analysis showed that differential expression of KEGG signaling pathways was significant between non-opioid-exposed specimens and opioid-exposed specimens, with a shift from a gene signature consistent with aerobic glycolysis to a gene signature consistent with the TCA cycle, nicotinate metabolism, and the cAMP signaling pathway. Together, these data suggest that extended opioid exposure changes the cellular metabolism and immune homeostasis of ccRCC, which might impact the response to therapy of these patients, especially if the therapy is targeting the microenvironment or metabolism of ccRCC tumors.

3.
Elife ; 122023 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-36735294

RESUMO

Newborns are unable to reach the adult-level humoral immune response partly due to the potent immunoregulatory role of IL-10. Increased IL-10 production by neonatal B cells has been attributed to the larger population of IL-10-producting CD43+ B-1 cells in neonates. Here, we show that neonatal mouse CD43- non-B-1 cells also produce substantial amounts of IL-10 following B cell antigen receptor (BCR) activation. In neonatal mouse CD43- non-B-1 cells, BCR engagement activated STAT5 under the control of phosphorylated forms of signaling molecules Syk, Btk, PKC, FAK, and Rac1. Neonatal STAT5 activation led to IL-6 production, which in turn was responsible for IL-10 production in an autocrine/paracrine fashion through the activation of STAT3. In addition to the increased IL-6 production in response to BCR stimulation, elevated expression of IL-6Rα expression in neonatal B cells rendered them highly susceptible to IL-6-mediated STAT3 phosphorylation and IL-10 production. Finally, IL-10 secreted from neonatal mouse CD43- non-B-1 cells was sufficient to inhibit TNF-α secretion by macrophages. Our results unveil a distinct mechanism of IL-6-dependent IL-10 production in BCR-stimulated neonatal CD19+CD43- B cells.


Assuntos
Interleucina-10 , Interleucina-6 , Animais , Camundongos , Animais Recém-Nascidos , Antígenos CD19/metabolismo , Interleucina-10/metabolismo , Interleucina-6/metabolismo , Fosforilação , Receptores de Antígenos de Linfócitos B/metabolismo , Fator de Transcrição STAT5/metabolismo , Leucossialina/imunologia
4.
Front Oncol ; 12: 858379, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35656514

RESUMO

The immune checkpoint programmed death-ligand 1 (PD-L1) is expressed on the cell surface of tumor cells and is key for maintaining an immunosuppressive microenvironment through its interaction with the programmed death 1 (PD-1). Clear cell renal cell carcinoma (ccRCC) is a highly immunogenic cancer characterized by an aberrant aerobic glycolytic metabolism and is known to overexpress PD-L1. Multiple immunotherapies have been approved for the treatment of ccRCC, including cytokines and immune checkpoint inhibitors. Recently the intrinsic role of PD-L1 and interferon gamma (IFNγ) signaling have been studied in several types of tumor cells, yet it remains unclear how they affect the metabolism and signaling pathways of ccRCC. Using metabolomics, metabolic assays and RNAseq, we showed that IFNγ enhanced aerobic glycolysis and tryptophan metabolism in ccRCC cells in vitro and induced the transcriptional expression of signaling pathways related to inflammation, cell proliferation and cellular energetics. These metabolic and transcriptional effects were partially reversed following transient PD-L1 silencing. Aerobic glycolysis, as well as signaling pathways related to inflammation, were not induced by IFNγ when PD-L1 was silenced, however, tryptophan metabolism and activation of Jak2 and STAT1 were maintained. Our data demonstrate that PD-L1 expression is required to mediate some of IFNγ's effect in ccRCC cells and highlight the importance of PD-L1 signaling in regulating the metabolism of ccRCC cells in response to inflammatory signals.

5.
AAPS J ; 23(2): 44, 2021 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-33719006

RESUMO

Anthracyclines are a class of chemotherapy drugs that are highly effective for the treatment of human cancers, but their clinical use is limited by associated dose-dependent cardiotoxicity. The precise mechanisms by which individual anthracycline induces cardiotoxicity are not fully understood. Human-induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) are emerging as a physiologically relevant model to assess drugs cardiotoxicity. Here, we describe an assay platform by coupling hiPSC-CMs and impedance measurement, which allows real-time monitoring of cardiomyocyte cellular index, beating amplitude, and beating rate. Using this approach, we have performed comparative studies on a panel of four anthracycline drugs (doxorubicin, epirubicin, idarubicin, and daunorubicin) which share a high degree of structural similarity but are associated with distinct cardiotoxicity profiles and maximum cumulative dose limits. Notably, results from our hiPSC-CMs impedance model (dose-dependent responses and EC50 values) agree well with the recommended clinical dose limits for these drugs. Using time-lapse imaging and RNAseq, we found that the differences in anthracycline cardiotoxicity are closely linked to extent of cardiomyocyte uptake and magnitude of activation/inhibition of several cellular pathways such as death receptor signaling, ROS production, and dysregulation of calcium signaling. The results provide molecular insights into anthracycline cardiac interactions and offer a novel assay system to more robustly assess potential cardiotoxicity during drug development.


Assuntos
Antraciclinas/efeitos adversos , Antibióticos Antineoplásicos/efeitos adversos , Cardiotoxicidade/etiologia , Miócitos Cardíacos/efeitos dos fármacos , Bioensaio/métodos , Sinalização do Cálcio/efeitos dos fármacos , Diferenciação Celular , Células Cultivadas , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos/métodos , Impedância Elétrica , Humanos , Células-Tronco Pluripotentes Induzidas/fisiologia , Microscopia Intravital/métodos , Miócitos Cardíacos/fisiologia , Estresse Oxidativo/efeitos dos fármacos , RNA-Seq , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Imagem com Lapso de Tempo
6.
Nat Commun ; 12(1): 832, 2021 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-33547304

RESUMO

The two T cell inhibitory receptors PD-1 and TIM-3 are co-expressed during exhausted T cell differentiation, and recent evidence suggests that their crosstalk regulates T cell exhaustion and immunotherapy efficacy; however, the molecular mechanism is unclear. Here we show that PD-1 contributes to the persistence of PD-1+TIM-3+ T cells by binding to the TIM-3 ligand galectin-9 (Gal-9) and attenuates Gal-9/TIM-3-induced cell death. Anti-Gal-9 therapy selectively expands intratumoral TIM-3+ cytotoxic CD8 T cells and immunosuppressive regulatory T cells (Treg cells). The combination of anti-Gal-9 and an agonistic antibody to the co-stimulatory receptor GITR (glucocorticoid-induced tumor necrosis factor receptor-related protein) that depletes Treg cells induces synergistic antitumor activity. Gal-9 expression and secretion are promoted by interferon ß and γ, and high Gal-9 expression correlates with poor prognosis in multiple human cancers. Our work uncovers a function for PD-1 in exhausted T cell survival and suggests Gal-9 as a promising target for immunotherapy.


Assuntos
Adenocarcinoma/terapia , Neoplasias do Colo/terapia , Galectinas/imunologia , Regulação Neoplásica da Expressão Gênica/imunologia , Proteína Relacionada a TNFR Induzida por Glucocorticoide/imunologia , Receptor Celular 2 do Vírus da Hepatite A/imunologia , Receptor de Morte Celular Programada 1/imunologia , Adenocarcinoma/genética , Adenocarcinoma/imunologia , Adenocarcinoma/mortalidade , Animais , Anticorpos/farmacologia , Antineoplásicos Imunológicos/farmacologia , Neoplasias do Colo/genética , Neoplasias do Colo/imunologia , Neoplasias do Colo/mortalidade , Galectinas/antagonistas & inibidores , Galectinas/genética , Proteína Relacionada a TNFR Induzida por Glucocorticoide/agonistas , Proteína Relacionada a TNFR Induzida por Glucocorticoide/genética , Receptor Celular 2 do Vírus da Hepatite A/genética , Humanos , Imunoterapia/métodos , Células Jurkat , Melanoma Experimental/genética , Melanoma Experimental/imunologia , Melanoma Experimental/mortalidade , Melanoma Experimental/terapia , Camundongos , Camundongos Endogâmicos BALB C , Receptor de Morte Celular Programada 1/genética , Ligação Proteica , Transdução de Sinais , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/imunologia , Neoplasias Cutâneas/mortalidade , Neoplasias Cutâneas/terapia , Análise de Sobrevida , Linfócitos T Citotóxicos/efeitos dos fármacos , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/patologia , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/patologia
7.
ACS Sens ; 5(2): 296-302, 2020 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-32073836

RESUMO

While monoclonal antibodies are the fastest-growing class of therapeutic agents, we lack a method that can directly quantify the on- and off-target binding affinities of newly developed therapeutic antibodies in crude cell lysates. As a result, some therapeutic antibody candidates could have a moderate on-target binding affinity but a high off-target binding affinity, which not only gives a reduced efficacy but triggers unwanted side effects. Here, we report a single-molecule counting method that precisely quantifies antibody-bound receptors, free receptors, and unbound antibodies in crude cell lysates, termed digital receptor occupancy assay (DRO). Compared to the traditional flow cytometry-based binding assay, DRO assay enables direct and digital quantification of the three molecular species in solution without the additional antibodies for competitive binding. When characterizing the therapeutic antibody, cetuximab, using DRO assay, we found the on-target binding ratio to be 65% and the binding constant (Kd) to be 2.4 nM, while the off-target binding causes the binding constant to decrease by 0.3 nM. Other than cultured cells, the DRO assay can be performed on tumor mouse xenograft models. Thus, DRO is a simple and highly quantitative method for cell-based antibody binding analysis which can be broadly applied to screen and validate new therapeutic antibodies.


Assuntos
Anticorpos/uso terapêutico , Afinidade de Anticorpos/fisiologia , Animais , Anticorpos/farmacologia , Humanos , Camundongos
8.
Cancer Cell ; 36(2): 168-178.e4, 2019 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-31327656

RESUMO

Reactivation of T cell immunity by PD-1/PD-L1 immune checkpoint blockade has been shown to be a promising cancer therapeutic strategy. However, PD-L1 immunohistochemical readout is inconsistent with patient response, which presents a clinical challenge to stratify patients. Because PD-L1 is heavily glycosylated, we developed a method to resolve this by removing the glycan moieties from cell surface antigens via enzymatic digestion, a process termed sample deglycosylation. Notably, deglycosylation significantly improves anti-PD-L1 antibody binding affinity and signal intensity, resulting in more accurate PD-L1 quantification and prediction of clinical outcome. This proposed method of PD-L1 antigen retrieval may provide a practical and timely approach to reduce false-negative patient stratification for guiding anti-PD-1/PD-L1 therapy.


Assuntos
Anticorpos/imunologia , Antígeno B7-H1/metabolismo , Imuno-Histoquímica , Neoplasias/metabolismo , Peptídeo-N4-(N-acetil-beta-glucosaminil) Asparagina Amidase/metabolismo , Processamento de Proteína Pós-Traducional , Manejo de Espécimes/métodos , Células A549 , Especificidade de Anticorpos , Antineoplásicos Imunológicos/uso terapêutico , Antígeno B7-H1/antagonistas & inibidores , Antígeno B7-H1/imunologia , Tomada de Decisão Clínica , Reações Falso-Negativas , Glicosilação , Humanos , Células Jurkat , Células MCF-7 , Neoplasias/tratamento farmacológico , Neoplasias/imunologia , Seleção de Pacientes , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Células THP-1
9.
Sci Rep ; 9(1): 3395, 2019 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-30833579

RESUMO

Derailed transmembrane receptor trafficking could be a hallmark of tumorigenesis and increased tumor invasiveness, but receptor dynamics have not been used to differentiate metastatic cancer cells from less invasive ones. Using single-particle tracking techniques, we  developed a phenotyping asssay named Transmembrane Receptor Dynamics (TReD), studied the dynamics of epidermal growth factor receptor (EGFR) in seven breast epithelial cell lines and developed a phenotyping assay named Transmembrane Receptor Dynamics (TReD). Here we show a clear evidence that increased EGFR diffusivity and enlarged EGFR confinement size in the plasma membrane (PM) are correlated with the enhanced metastatic potential in these cell lines. By comparing the TReD results with the gene expression profiles, we found a clear negative correlation between the EGFR diffusivities and the breast cancer luminal differentiation scores (r = -0.75). Upon the induction of epithelial-mesenchymal transition (EMT), EGFR diffusivity significantly increased for the non-tumorigenic MCF10A (99%) and the non-invasive MCF7 (56%) cells, but not for the highly metastatic MDA-MB-231 cell. We believe that the reorganization of actin filaments during EMT modified the PM structures, causing the receptor dynamics to change. TReD can thus serve as a new biophysical marker to probe the metastatic potential of cancer cells and even to monitor the transition of metastasis.


Assuntos
Neoplasias da Mama/metabolismo , Receptores ErbB/metabolismo , Actinas/metabolismo , Neoplasias da Mama/genética , Linhagem Celular Tumoral , Transição Epitelial-Mesenquimal/genética , Transição Epitelial-Mesenquimal/fisiologia , Receptores ErbB/genética , Feminino , Imunofluorescência , Regulação Neoplásica da Expressão Gênica/genética , Regulação Neoplásica da Expressão Gênica/fisiologia , Humanos
10.
Biosens Bioelectron ; 117: 97-103, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-29890396

RESUMO

Protein expression level is critically related to the cell physiological function. However, current methodologies such as Western blot (WB) and Immunohistochemistry (IHC) in analyzing the protein level are rather semi-quantitative and without the information of actual protein concentration. We have developed a microfluidic technique termed a "flow-proteometric platform for analyzing protein concentration (FAP)" that can measure the concentration of a target protein in cells or tissues without the requirement of a calibration standard, e.g., the purified target molecules. To validate our method, we tested a number of control samples with known target protein concentrations and showed that the FAP measurement resulted in concentrations that well matched the actual concentrations in the control samples (coefficient of determination [R2], 0.998), demonstrating a dynamic range of concentrations from 0.13 to 130 pM of a detection for 2 min. We successfully determined a biomarker protein (for predicting the treatment response of cancer immune check-point therapy) PD-L1 concentration in cancer cell lines (HeLa PD-L1 and MDA-MB-231) and breast cancer patient tumor tissues without any prior process of sample purification and standard line construction. Therefore, FAP is a simple, faster, and reliable method to measure the protein concentration in cells and tissues, which can support the conventional methods such as WB and IHC to determine the actual protein level.


Assuntos
Antígeno B7-H1/análise , Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , Proteômica , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Células HeLa , Humanos , Limite de Detecção
11.
Cancer Cell ; 33(4): 752-769.e8, 2018 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-29606349

RESUMO

Pancreatic ribonuclease (RNase) is a secreted enzyme critical for host defense. We discover an intrinsic RNase function, serving as a ligand for epidermal growth factor receptor (EGFR), a member of receptor tyrosine kinase (RTK), in pancreatic ductal adenocarcinoma (PDAC). The closely related bovine RNase A and human RNase 5 (angiogenin [ANG]) can trigger oncogenic transformation independently of their catalytic activities via direct association with EGFR. Notably, high plasma ANG level in PDAC patients is positively associated with response to EGFR inhibitor erlotinib treatment. These results identify a role of ANG as a serum biomarker that may be used to stratify patients for EGFR-targeted therapies, and offer insights into the ligand-receptor relationship between RNase and RTK families.


Assuntos
Carcinoma Ductal Pancreático/patologia , Cloridrato de Erlotinib/farmacologia , Neoplasias Pancreáticas/patologia , Ribonuclease Pancreático/sangue , Ribonuclease Pancreático/metabolismo , Animais , Sítios de Ligação , Biomarcadores/sangue , Carcinoma Ductal Pancreático/sangue , Carcinoma Ductal Pancreático/tratamento farmacológico , Bovinos , Linhagem Celular Tumoral , Receptores ErbB/química , Receptores ErbB/metabolismo , Cloridrato de Erlotinib/uso terapêutico , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HeLa , Humanos , Camundongos , Transplante de Neoplasias , Neoplasias Pancreáticas/sangue , Neoplasias Pancreáticas/tratamento farmacológico , Ribonuclease Pancreático/química , Transdução de Sinais
12.
Cancer Cell ; 33(2): 187-201.e10, 2018 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-29438695

RESUMO

Protein glycosylation provides proteomic diversity in regulating protein localization, stability, and activity; it remains largely unknown whether the sugar moiety contributes to immunosuppression. In the study of immune receptor glycosylation, we showed that EGF induces programmed death ligand 1 (PD-L1) and receptor programmed cell death protein 1 (PD-1) interaction, requiring ß-1,3-N-acetylglucosaminyl transferase (B3GNT3) expression in triple-negative breast cancer. Downregulation of B3GNT3 enhances cytotoxic T cell-mediated anti-tumor immunity. A monoclonal antibody targeting glycosylated PD-L1 (gPD-L1) blocks PD-L1/PD-1 interaction and promotes PD-L1 internalization and degradation. In addition to immune reactivation, drug-conjugated gPD-L1 antibody induces a potent cell-killing effect as well as a bystander-killing effect on adjacent cancer cells lacking PD-L1 expression without any detectable toxicity. Our work suggests targeting protein glycosylation as a potential strategy to enhance immune checkpoint therapy.


Assuntos
Anticorpos Monoclonais/farmacologia , Linfócitos do Interstício Tumoral/efeitos dos fármacos , Receptor de Morte Celular Programada 1/imunologia , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/imunologia , Animais , Linhagem Celular Tumoral , Feminino , Humanos , Linfócitos do Interstício Tumoral/imunologia , Camundongos Endogâmicos BALB C , N-Acetilglucosaminiltransferases/efeitos dos fármacos , N-Acetilglucosaminiltransferases/metabolismo , Neoplasias de Mama Triplo Negativas/metabolismo
13.
Soft Robot ; 4(4): 390-399, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29251562

RESUMO

Collagen microparticles have recently gained more attention as viable cell confinement blocks in many biomedical research fields. Small volume and high surface area of collagen structure improve cell confinement, viability, and proliferation. Moreover, dense collagen fiber structure can protect cells from immune destruction. The ability to produce collagen microparticles in an accurate and reliable way is of upmost importance to the advancement of many biomedical researches, especially cancer research and tissue engineering. Currently, no such fabrication technique exists due to inherent fragility of collagen. Herein, we report the very first platform, pneumatically actuated soft micromold (PASMO) device, which addresses challenges in collagen microparticle production. Our new platform uses a soft micromold with a pneumatic actuator that can produce arbitrary shapes of collagen microstructures precisely from 100 µm to over 2 mm in range and can encapsulate cells inside without damaging the shape. The duplication accuracy of more than 96% in dimensions and 90% in depth has been demonstrated. The density of collagen fiber distribution is determined to be 86.57%, which is higher than that of collagen microparticles produced by other methods. We have confirmed cell viability in collagen microparticles. We also produce Matrigel™ particles as tool to develop a xenograft cancer model. The results demonstrate that Matrigel particles created by the PASMO device can reduce cell scattering for the xenograft model and the uniformity of tumors developed in mice is 12-fold improved, which can lead to an increased accuracy of cancer metastasis studies and drug screening research. These breakthroughs in the production of modular microparticles will push the boundaries of cancer research in the near future.

14.
Mol Cell ; 67(5): 733-743.e4, 2017 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-28844863

RESUMO

Nuclear receptors recruit multiple coactivators sequentially to activate transcription. This "ordered" recruitment allows different coactivator activities to engage the nuclear receptor complex at different steps of transcription. Estrogen receptor (ER) recruits steroid receptor coactivator-3 (SRC-3) primary coactivator and secondary coactivators, p300/CBP and CARM1. CARM1 recruitment lags behind the binding of SRC-3 and p300 to ER. Combining cryo-electron microscopy (cryo-EM) structure analysis and biochemical approaches, we demonstrate that there is a close crosstalk between early- and late-recruited coactivators. The sequential recruitment of CARM1 not only adds a protein arginine methyltransferase activity to the ER-coactivator complex, it also alters the structural organization of the pre-existing ERE/ERα/SRC-3/p300 complex. It induces a p300 conformational change and significantly increases p300 HAT activity on histone H3K18 residues, which, in turn, promotes CARM1 methylation activity on H3R17 residues to enhance transcriptional activity. This study reveals a structural role for a coactivator sequential recruitment and biochemical process in ER-mediated transcription.


Assuntos
Proteínas Adaptadoras de Sinalização CARD/metabolismo , Proteína p300 Associada a E1A/metabolismo , Receptor alfa de Estrogênio/metabolismo , Guanilato Ciclase/metabolismo , Coativador 3 de Receptor Nuclear/metabolismo , Transcrição Gênica , Acetilação , Sítios de Ligação , Proteínas Adaptadoras de Sinalização CARD/química , Proteínas Adaptadoras de Sinalização CARD/genética , Microscopia Crioeletrônica , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Proteína p300 Associada a E1A/química , Proteína p300 Associada a E1A/genética , Receptor alfa de Estrogênio/química , Receptor alfa de Estrogênio/genética , Guanilato Ciclase/química , Guanilato Ciclase/genética , Células HEK293 , Células HeLa , Histonas/química , Histonas/metabolismo , Humanos , Células MCF-7 , Metilação , Modelos Moleculares , Complexos Multiproteicos , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Coativador 3 de Receptor Nuclear/química , Coativador 3 de Receptor Nuclear/genética , Regiões Promotoras Genéticas , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Relação Estrutura-Atividade , Fatores de Tempo , Fatores de Transcrição , Ativação Transcricional , Transfecção
15.
Clin Cancer Res ; 23(14): 3711-3720, 2017 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-28167507

RESUMO

Purpose: To explore whether a cross-talk exists between PARP inhibition and PD-L1/PD-1 immune checkpoint axis, and determine whether blockade of PD-L1/PD-1 potentiates PARP inhibitor (PARPi) in tumor suppression.Experimental Design: Breast cancer cell lines, xenograft tumors, and syngeneic tumors treated with PARPi were assessed for PD-L1 expression by immunoblotting, IHC, and FACS analyses. The phospho-kinase antibody array screen was used to explore the underlying mechanism of PARPi-induced PD-L1 upregulation. The therapeutic efficacy of PARPi alone, PD-L1 blockade alone, or their combination was tested in a syngeneic tumor model. The tumor-infiltrating lymphocytes and tumor cells isolated from syngeneic tumors were analyzed by CyTOF and FACS to evaluate the activity of antitumor immunity in the tumor microenvironment.Results: PARPi upregulated PD-L1 expression in breast cancer cell lines and animal models. Mechanistically, PARPi inactivated GSK3ß, which in turn enhanced PARPi-mediated PD-L1 upregulation. PARPi attenuated anticancer immunity via upregulation of PD-L1, and blockade of PD-L1 resensitized PARPi-treated cancer cells to T-cell killing. The combination of PARPi and anti-PD-L1 therapy compared with each agent alone significantly increased the therapeutic efficacy in vivoConclusions: Our study demonstrates a cross-talk between PARPi and tumor-associated immunosuppression and provides evidence to support the combination of PARPi and PD-L1 or PD-1 immune checkpoint blockade as a potential therapeutic approach to treat breast cancer. Clin Cancer Res; 23(14); 3711-20. ©2017 AACR.


Assuntos
Antígeno B7-H1/imunologia , Neoplasias da Mama/tratamento farmacológico , Poli(ADP-Ribose) Polimerase-1/imunologia , Inibidores de Poli(ADP-Ribose) Polimerases/administração & dosagem , Receptor de Morte Celular Programada 1/imunologia , Animais , Antígeno B7-H1/genética , Neoplasias da Mama/genética , Neoplasias da Mama/imunologia , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Terapia de Imunossupressão , Linfócitos do Interstício Tumoral/efeitos dos fármacos , Linfócitos do Interstício Tumoral/imunologia , Camundongos , Poli(ADP-Ribose) Polimerase-1/antagonistas & inibidores , Inibidores de Poli(ADP-Ribose) Polimerases/imunologia , Receptor de Morte Celular Programada 1/genética , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/imunologia , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Am J Cancer Res ; 7(12): 2587-2599, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29312811

RESUMO

Arginine methylation of the epidermal growth factor receptor (meEGFR) increases the binding affinity of EGFR ligands and is reported to have a role in predicting response to anti-EGFR agents. This study investigated the predictive impact of meEGFR in metastatic colorectal cancer (mCRC) patients treated with anti-EGFR agents. Two patient cohorts were evaluated. Cohort 1 consisted of mCRC patients with documented disease progression following anti-EGFR treatment. Circulating tumor cells (CTCs) were isolated and distinguished based on CD45- and Epcam+. Cohort 2 consisted of formalin fixed paraffin-embedded (FFPE) blocks from a prospective cohort. meEGFR in both cohorts was identified by positive staining for me-R198/200 EGFR signal. CTCs were identified in 30 out of 47 cases in cohort 1. Of those 30, meEGFR-CTCs were identified in 19 cases. Mean total meEGFR-CTCs counts was 2.3 (range 0-30) cells per 7.5 ml. There was no association between meEGFR-CTCs and clinic-pathological-molecular features. In RASwt/BRAFwt patients with high levels of meEGFR-CTCs ratio (≥ 0.23) had significantly inferior PFS with anti-EGFR treatment (HR = 3.4, 95% CI 1.5-7.9, P = 0.004). By contrast, high levels of meEGFR in the untreated tumor tissues had no correlation with anti-EGFR treatment duration in cohort 2. Therefore, meEGFR-CTCs may have the potential to serve as a "liquid biopsy" biomarker to predict anti-EGFR treatment efficacy.

17.
Biophys J ; 111(10): 2214-2227, 2016 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-27851944

RESUMO

Whereas important discoveries made by single-particle tracking have changed our view of the plasma membrane organization and motor protein dynamics in the past three decades, experimental studies of intracellular processes using single-particle tracking are rather scarce because of the lack of three-dimensional (3D) tracking capacity. In this study we use a newly developed 3D single-particle tracking method termed TSUNAMI (Tracking of Single particles Using Nonlinear And Multiplexed Illumination) to investigate epidermal growth factor receptor (EGFR) trafficking dynamics in live cells at 16/43 nm (xy/z) spatial resolution, with track duration ranging from 2 to 10 min and vertical tracking depth up to tens of microns. To analyze the long 3D trajectories generated by the TSUNAMI microscope, we developed a trajectory analysis algorithm, which reaches 81% segment classification accuracy in control experiments (termed simulated movement experiments). When analyzing 95 EGF-stimulated EGFR trajectories acquired in live skin cancer cells, we find that these trajectories can be separated into three groups-immobilization (24.2%), membrane diffusion only (51.6%), and transport from membrane to cytoplasm (24.2%). When EGFRs are membrane-bound, they show an interchange of Brownian diffusion and confined diffusion. When EGFRs are internalized, transitions from confined diffusion to directed diffusion and from directed diffusion back to confined diffusion are clearly seen. This observation agrees well with the model of clathrin-mediated endocytosis.


Assuntos
Receptores ErbB/metabolismo , Imageamento Tridimensional , Microscopia , Algoritmos , Linhagem Celular Tumoral , Membrana Celular/metabolismo , Citoplasma/metabolismo , Humanos , Transporte Proteico
18.
Cancer Res ; 76(23): 7049-7058, 2016 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-27758883

RESUMO

The oncogenic transcription factor Gli1 is a critical effector in the Hedgehog (Hh) pathway, which is necessary for the development and progression of pancreatic ductal adenocarcinoma (PDAC). Although TGFß and K-Ras are known regulators of Gli1 gene transcription in this setting, it is not understood how Gli1 functional activity is regulated. Here, we report the identification of Gli1 as a substrate for the protein arginine N-methyltransferase PRMT1 in PDAC. We found that PRMT1 methylates Gli1 at R597, promoting its transcriptional activity by enhancing the binding of Gli1 to its target gene promoters. Interruption of Gli1 methylation attenuates oncogenic functions of Gli1 and sensitizes PDAC cells to gemcitabine treatment. In human PDAC specimens, the levels of both total Gli1 and methylated Gli1 were correlated positively with PRMT1 protein levels. Notably, PRMT1 regulated Gli1 independently of the canonical Hh pathway as well as the TGFß/Kras-mediated noncanonical Hh pathway, thereby signifying a novel regulatory mechanism for Gli1 transcriptional activity. Taken together, our results identified a new posttranslational modification of Gli1 that underlies its pivotal oncogenic functions in PDAC. Cancer Res; 76(23); 7049-58. ©2016 AACR.


Assuntos
Adenocarcinoma/genética , Carcinogênese/genética , Neoplasias Pancreáticas/genética , Proteína GLI1 em Dedos de Zinco/genética , Adenocarcinoma/patologia , Humanos , Metilação , Neoplasias Pancreáticas/patologia , Transdução de Sinais , Transfecção , Proteína GLI1 em Dedos de Zinco/metabolismo , Neoplasias Pancreáticas
19.
Curr Protoc Mol Biol ; 114: 20.11.1-20.11.22, 2016 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-27038387

RESUMO

Signal transduction is essential for maintaining normal cell physiological functions, and deregulation of signaling can lead to diseases such as diabetes and cancers. Some of the major players in signal delivery are molecular complexes composed of proteins and nucleic acids. This unit describes a technique called microchannel for multiparameter analysis of proteins in a single complex (mMAPS) for analyzing and quantifying individual target signaling complexes. mMAPS is a flow-proteometric system that allows detection of individual proteins or complexes flowing through a microfluidic channel. Specific target proteins and nucleic acids labeled by fluorescent tags are harvested from tissues or cultured cells for analysis by the mMAPS system. Overall, mMAPS enables both detection of multiple components within a single complex and direct quantification of different populations of molecular complexes in one setting in a short timeframe and requiring very low sample input.


Assuntos
Técnicas Analíticas Microfluídicas , Proteínas , Proteômica/métodos , Animais , Calibragem , Células Cultivadas , Humanos , Proteínas/química , Proteínas/metabolismo , Proteômica/instrumentação , Controle de Qualidade
20.
Cancer Res ; 76(6): 1451-62, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26759241

RESUMO

Epithelial-to-mesenchymal transition (EMT) is an essential physiologic process that promotes cancer cell migration, invasion, and metastasis. Several lines of evidence from both cellular and genetic studies suggest that AKT1/PKBα, but not AKT2 or AKT3, serves as a negative regulator of EMT and breast cancer metastasis. However, the underlying mechanism by which AKT1 suppresses EMT remains poorly defined. Here, we demonstrate that phosphorylation of Twist1 by AKT1 is required for ß-TrCP-mediated Twist1 ubiquitination and degradation. The clinically used AKT inhibitor MK-2206, which possesses higher specificity toward AKT1, stabilized Twist1 and enhanced EMT in breast cancer cells. However, we discovered that resveratrol, a naturally occurring compound, induced ß-TrCP-mediated Twist1 degradation to attenuate MK-2206-induced EMT in breast cancer cells. Taken together, our findings demonstrate that resveratrol counteracts the unexpected metastatic potential induced by anti-AKT therapy and therefore suggest that the addition of resveratrol to an anti-AKT therapeutic regimen may provide extra support for limiting EMT.


Assuntos
Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Transição Epitelial-Mesenquimal/fisiologia , Fosforilação/fisiologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteína 1 Relacionada a Twist/metabolismo , Animais , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Movimento Celular/fisiologia , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Feminino , Compostos Heterocíclicos com 3 Anéis/farmacologia , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Fosforilação/efeitos dos fármacos , Proteólise/efeitos dos fármacos , Resveratrol , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Estilbenos/farmacologia , Proteínas Contendo Repetições de beta-Transducina/metabolismo
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