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1.
Eur J Immunol ; 50(6): 880-890, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32052406

RESUMO

NK cells are innate lymphocytes responsible for lysis of pathogen-infected and transformed cells. One of the major activating receptors required for target cell recognition is the NK group 2D (NKG2D) receptor. Numerous reports show the necessity of NKG2D for effective tumor immune surveillance. Further studies identified NKG2D as a key element allowing tumor immune escape. We here use a mouse model with restricted deletion of NKG2D in mature NKp46+ cells (NKG2DΔNK ). NKG2DΔNK NK cells develop normally, have an unaltered IFN-γ production but kill tumor cell lines expressing NKG2D ligands (NKG2DLs) less efficiently. However, upon long-term stimulation with IL-2, NKG2D-deficient NK cells show increased levels of the lytic molecule perforin. Thus, our findings demonstrate a dual function of NKG2D for NK cell cytotoxicity; while NKG2D is a crucial trigger for cytotoxicity of tumor cells expressing activating ligands it is also capable to limit perforin production in IL-2 activated NK cells.


Assuntos
Interleucina-2/farmacologia , Células Matadoras Naturais/imunologia , Subfamília K de Receptores Semelhantes a Lectina de Células NK/imunologia , Proteínas Citotóxicas Formadoras de Poros/imunologia , Animais , Linhagem Celular Tumoral , Imunidade Celular/efeitos dos fármacos , Imunidade Celular/genética , Interferon gama/genética , Interferon gama/imunologia , Células Matadoras Naturais/patologia , Camundongos , Camundongos Knockout , Subfamília K de Receptores Semelhantes a Lectina de Células NK/genética , Proteínas Citotóxicas Formadoras de Poros/genética
2.
Int J Mol Sci ; 22(5)2021 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-33668117

RESUMO

The term trogocytosis refers to a rapid bidirectional and active transfer of surface membrane fragment and associated proteins between cells. The trogocytosis requires cell-cell contact, and exhibits fast kinetics and the limited lifetime of the transferred molecules on the surface of the acceptor cells. The biological actions of trogocytosis include information exchange, cell clearance of unwanted tissues in embryonic development, immunoregulation, cancer surveillance/evasion, allogeneic cell survival and infectious pathogen killing or intercellular transmission. In the present review, we will extensively review all these aspects. In addition to its biological significance, aberrant trogocytosis in the immune system leading to autoimmunity and immune-mediated inflammatory diseases will also be discussed. Finally, the prospective investigations for further understanding the molecular basis of trogocytosis and its clinical applications will also be proposed.


Assuntos
Autoimunidade/imunologia , Membrana Celular/imunologia , Sistema Imunitário/imunologia , Ativação Linfocitária/imunologia , Linfócitos/imunologia , Animais , Apresentação de Antígeno , Comunicação Celular , Humanos
3.
Cell Immunol ; 352: 104081, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32143838

RESUMO

Mice that express a single transgenic T cell receptor have a low incidence of T cell lymphoma development. We investigated whether this tumor development is restricted by surveillance mechanisms that are exerted by IL-15-dependent cells. Lymphoma incidence was increased to between 30 and 60% when TCR transgenes were expressed in IL-15-deficient mice. Mice in which NK cells had been depleted genetically or with neutralizing antibodies allowed lymphoma growth while the absence of CD8 T cells was without consequence. Half of the emerged T cell lymphomas carried Notch1 mutations. The distinct phenotype of the lymphomas involved expression of PD1, CD30, CD24, the stress receptor ligand Mult1 and MHC class I down-regulation. NK cells were able to directly lyse lymphoma cells, and neutralizations of Mult1 and class I expression prevented NK cell degranulation. Together these data support an involvement of NK cells in tumor surveillance of nascent T cell lymphomas.


Assuntos
Células Matadoras Naturais/metabolismo , Linfoma de Células T/imunologia , Receptores de Antígenos de Linfócitos T/metabolismo , Animais , Linfócitos T CD8-Positivos/imunologia , Diferenciação Celular , Feminino , Humanos , Interleucina-15/imunologia , Interleucina-15/metabolismo , Células Matadoras Naturais/imunologia , Ativação Linfocitária , Linfoma/patologia , Linfoma de Células T/genética , Linfoma de Células T/prevenção & controle , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Receptor Notch1/genética , Receptor Notch1/metabolismo , Receptores de Antígenos de Linfócitos T/imunologia
4.
Semin Cancer Biol ; 44: 106-116, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28442298

RESUMO

Breast cancer ranks first among female cancer-related deaths in Western countries. As the primary tumor can often be controlled by surgical resection, the survival of women with breast cancer is closely linked to the incidence of distant metastases. Molecular screening by next generation sequencing highlighted the spatial and temporal heterogeneity of solid tumors as well as the clonal evolution of cancer cells during progression and under treatment pressure. Such findings question whether an optimal assessment of disease progression and a screening for druggable mutations should be based on molecular features of primary or recurrent/metastatic lesions and therefore represent a crucial element for failure or success of personalized medicine. In fact, new targeted therapies may induce only short-term benefit annulled by the emergence of resistant clones with new driver mutations which would need to be rapidly and reliably identified. Serial tissue sampling is therefore essential but, unfortunately, also represents a problem since biopsies from solid lesions, which are invasive and potentially painful and risky, cannot be easily repeatedly sampled, are inaccessible or may not fully reflect tumor heterogeneity. The need to early detect and strike this "moving target" is now directing the scientific community toward liquid biopsy-based biomarkers, which include circulating tumor cells (CTC) and cell-free circulating tumor DNA (ctDNA), can be repeatedly assessed through non-invasive and easy-to-perform procedures and may act as reliable read-outs of functional and molecular features of recurrent/metastatic lesions. In this review we summarize the outcome of CTCs and ctDNA in breast cancer, with special reference on their role on unveiling and overcoming tumor heterogeneity, on their potential relevance for tumor surveillance and monitoring, and for the selection of therapeutic options. Finally, we propose integration between blood-based molecular and clinical approaches for monitoring disease progression according to the specific pattern of recurrence of the most aggressive breast cancer molecular subtypes.


Assuntos
Biomarcadores Tumorais/sangue , Neoplasias da Mama/sangue , DNA Tumoral Circulante/sangue , Heterogeneidade Genética , Neoplasias da Mama/patologia , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Células Neoplásicas Circulantes/patologia
5.
Cell Physiol Biochem ; 51(3): 1103-1118, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30476917

RESUMO

BACKGROUND/AIMS: Cellular senescence, or permanent growth arrest, is known as an effective tumor suppressor mechanism that can be induced by different stressors, such as oncogenes, chemotherapeutics or cytokine cocktails. Previous studies demonstrated that the growth-repressing state of oncogene-induced senescent cells depends on argonaute protein 2 (Ago2)-mediated transcriptional gene silencing and Ago2/Rb corepression of E2F-dependent cell cycle genes. Cytokine-induced senescence (CIS) likewise depends on activation of the p16Ink4a/Rb pathway, and consecutive inactivation of the E2F family of transcription factors. In the present study, we therefore analyzed the role of Ago2 in CIS. METHODS: Human cancer cell lines were treated with interferon-gamma (IFN-γ) and tumor necrosis factor (TNF) to induce senescence. Senescence was determined by growth assays and measurement of senescence-associated ß-galactosidase (SA-ß-gal) activity, Ago2 translocation by Ago2/ Ki67 immunofluorescence staining and western blot analysis, and gene transcription by quantitative polymerase chain reaction (qPCR). RESULTS: IFN-γ and TNF permanently stopped cell proliferation and time-dependently increased SA-ß-gal activity. After 24 - 48 h of cytokine treatment, Ago2 translocated from the cytoplasm into the nucleus of Ki67-negative cells, an effect which was shown to be reversible. Importantly, the proinflammatory cytokine cocktail suppressed Ago2-regulated cell cycle control genes, and siRNA-mediated depletion of Ago2 interfered with cytokine-induced growth inhibition. CONCLUSION: IFN-γ and TNF induce a stable cell cycle arrest of cancer cells that is accompanied by a fast nuclear Ago2 translocation and repression of Ago2-regulated cell cycle control genes. As Ago2 downregulation impairs cytokine-induced growth regulation, Ago2 may contribute to tissue homeostasis in human cancers.


Assuntos
Proteínas Argonautas/metabolismo , Senescência Celular , Citocinas/metabolismo , Neoplasias/metabolismo , Transporte Ativo do Núcleo Celular , Proliferação de Células , Sobrevivência Celular , Humanos , Interferon gama/metabolismo , Células MCF-7 , Fatores de Necrose Tumoral/metabolismo
6.
Int Immunol ; 27(3): 161-6, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25568303

RESUMO

Drak2 is a promising therapeutic target to treat organ-specific autoimmune diseases such as type 1 diabetes and multiple sclerosis without causing generalized immune suppression. Inhibition of Drak2 may also prevent graft rejection following organ transplantation. However, Drak2 may function as a critical tumor suppressor, which would challenge the prospect of targeting Drak2 for therapeutic treatment. Thus, we examined the susceptibility of Drak2 (-/-) mice in several tumor models. We show that Drak2 is not required to prevent tumor formation in a variety of settings. Therefore, Drak2 does not function as an essential tumor suppressor in in vivo tumor models. These data further validate Drak2 as a viable therapeutic target to treat autoimmune disease and graft rejection. Importantly, these data also indicate that while Drak2 may induce apoptosis when overexpressed in cell lines, it is not an essential tumor suppressor.


Assuntos
Diabetes Mellitus Tipo 1/tratamento farmacológico , Rejeição de Enxerto/prevenção & controle , Vigilância Imunológica , Esclerose Múltipla/tratamento farmacológico , Transplante de Órgãos , Proteínas Serina-Treonina Quinases/metabolismo , Sarcoma/metabolismo , Animais , Apoptose , Linhagem Celular Tumoral , Modelos Animais de Doenças , Rejeição de Enxerto/etiologia , Humanos , Terapia de Imunossupressão , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Serina-Treonina Quinases/genética , Sarcoma/tratamento farmacológico , Proteínas Supressoras de Tumor/metabolismo
7.
Front Immunol ; 15: 1428653, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39185404

RESUMO

The p53 protein, encoded by TP53, is a tumor suppressor that plays a critical role in regulating apoptosis, cell cycle regulation, and angiogenesis in tumor cells via controlling various downstream signals. Natural killer (NK) cell-mediated immune surveillance is a vital self-defense mechanism against cancer and other diseases, with NK cell activity regulated by various mechanisms. Among these, p53 plays a significant role in immune regulation by maintaining the homeostasis and functionality of NK cells. It enhances the transcriptional activity of NK cell-activating ligands and downregulates inhibitory ligands to boost NK cell activation and tumor-killing efficacy. Additionally, p53 influences NK cell cytotoxicity by promoting apoptosis, autophagy, and ferroptosis in different tumor cells. p53 is involved in the regulation of NK cell activity and effector functions through multiple pathways. p53 also plays a pivotal role in the tumor microenvironment (TME), regulating the activity of NK cells. NK cells are critical components of the TME and are capable of directly killing tumor cells. And p53 mutates in numerous cancers, with the most common alteration being a missense mutation. These mutations are commonly associated with poor survival rates in patients with cancer. This review details p53's role in NK cell tumor immunosurveillance, summarizing how p53 enhances NK cell recognition and tumor destruction. We also explore the potential applications of p53 in tumor immunotherapy, discussing strategies for modulating p53 to enhance NK cell function and improve the efficacy of tumor immunotherapy, along with the associated challenges. Understanding the interaction between p53 and NK cells within the TME is crucial for advancing NK cell-based immunotherapy and developing p53-related novel therapeutics.


Assuntos
Células Matadoras Naturais , Neoplasias , Microambiente Tumoral , Proteína Supressora de Tumor p53 , Humanos , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/imunologia , Neoplasias/imunologia , Microambiente Tumoral/imunologia , Animais , Imunoterapia/métodos , Citotoxicidade Imunológica
8.
Front Immunol ; 13: 944872, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36131910

RESUMO

Structural and functional variability of human leukocyte antigen (HLA) is the foundation for competent adaptive immune responses against pathogen and tumor antigens as it assures the breadth of the presented immune-peptidome, theoretically sustaining an efficient and diverse T cell response. This variability is presumably the result of the continuous selection by pathogens, which over the course of evolution shaped the adaptive immune system favoring the assortment of a hyper-polymorphic HLA system able to elaborate efficient immune responses. Any genetic alteration affecting this diversity may lead to pathological processes, perturbing antigen presentation capabilities, T-cell reactivity and, to some extent, natural killer cell functionality. A highly variable germline HLA genotype can convey immunogenetic protection against infections, be associated with tumor surveillance or influence response to anti-neoplastic treatments. In contrast, somatic aberrations of HLA loci, rearranging the original germline configuration, theoretically decreasing its variability, can facilitate mechanisms of immune escape that promote tumor growth and immune resistance. The purpose of the present review is to provide a unified and up-to-date overview of the pathophysiological consequences related to the perturbations of the genomic heterogeneity of HLA complexes and their impact on human diseases, with a special focus on cancer.


Assuntos
Evasão da Resposta Imune , Neoplasias , Antígenos de Neoplasias , Antígenos HLA/genética , Antígenos de Histocompatibilidade Classe I , Antígenos de Histocompatibilidade Classe II , Humanos , Neoplasias/genética
9.
J Neuroimaging ; 32(6): 1185-1192, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36045502

RESUMO

BACKGROUND AND PURPOSE: High-grade glioma (HGG), including glioblastoma, is the most common primary brain neoplasm and has a dismal prognosis. After initial treatment, follow-up decisions are guided by longitudinal MRI performed at routine intervals. The Brain Tumor Reporting and Data System (BT-RADS) is a proposed structured reporting system for posttreatment brain MRIs. The purpose of this study is to determine the relationship between BT-RADS scores and overall survival in HGG patients. METHODS: Chart review of grade 4 glioma patients who had an MRI at a single institution from November 2018 to November 2019 was performed. BT-RADS scores, tumor characteristics, and overall survival were recorded. Likelihood of improvement, stability, or worsening on the subsequent study was calculated for each score. Survival analysis was performed using Kaplan-Meier method, log-rank test, and a time-dependent cox model. Significance level of .05 was used. RESULTS: The study identified 91 HGG patients who underwent a total of 538 MRIs. Mean age of patients was 57 years old. Score with the highest likelihood for worsening on the next follow-up was 3b. The risk of death was 53% higher with each incremental increase in BT-RADS scores (hazard ratio, 1.53; 95% confidence interval [CI], 1.07-2.19; p = .019). The risk of death was 167% higher in O-6-methylguanine-DNA-methyltransferase unmethylated tumors (hazard ratio, 2.67; 95% CI, 1.34-5.33; p = .005). CONCLUSIONS: BT-RADS scores can be used as a reference guide to anticipate whether patients' subsequent MRI will be improved, stable, or worsened. The scoring system can also be used to predict clinical outcomes and prognosis.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Glioma , Humanos , Pessoa de Meia-Idade , Glioma/diagnóstico por imagem , Glioma/patologia , Neoplasias Encefálicas/patologia , Prognóstico , Imageamento por Ressonância Magnética , Estudos Retrospectivos
10.
Clin Imaging ; 87: 1-4, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35439719

RESUMO

PURPOSE: To evaluate postoperative serum thyroglobulin (Tg) as a reliable tumor marker in low-risk differentiated thyroid cancer (DTC). METHODS: Two hundred and three patients met the selection criteria of >18 years old; who had undergone total or near total thyroidectomy; had a postoperative Tg, and had undergone 131I pre ablation whole body scan (PA-WBS). The primary endpoint was the correlation between Tg level and functional remnant thyroid tissues. Outcomes were categorized as concordant and discordant. Concordant results were positive Tg (>1 ng/ml) with positive PA-WBS or negative Tg (<1 ng/ml) with negative PA-WBS. Discordant results were negative Tg with a positive PA-WBS or positive Tg with a negative PA-WBS. To increase the sensitivity of Tg detection, we evaluated Tg in patients with high thyroid stimulating hormone (TSH) with serum level >30 mU/l on thyroxine withdrawal protocol. RESULTS: One hundred ten patients (54.1%) had discordant results (p < 0.05) with positive PA-WBS and Tg <1 ng/ml, while 93 patients (45.9%) had concordant results. For concordant results, 88 patients had positive PA-WBS and Tg >1 ng/ml, and 5 patients had negative PA-WBS and Tg <1 ng/ml. There was no patient with Tg >1 ng/ml and negative PA-WBS. There were 74 patients with high TSH (>30 mU/l) on abstention (thyroxine withdrawal protocol). Twenty-four (32.5%) had discordant results (p < 0.001) and 50 (67.5%) had concordant results. CONCLUSION: There is low correlation between postoperative Tg and PA-WBS. The sole use of Tg as a serum biomarker for postoperative disease status may not be reliable.


Assuntos
Adenocarcinoma , Tireoglobulina , Neoplasias da Glândula Tireoide , Humanos , Radioisótopos do Iodo/uso terapêutico , Cintilografia , Tireoglobulina/sangue , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/cirurgia , Tireotropina , Tiroxina , Imagem Corporal Total
11.
Cell Mol Immunol ; 19(8): 944-956, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35821253

RESUMO

Patients with type 2 diabetes mellitus (T2DM) have an increased risk of cancer. The effect of glucose metabolism on γδ T cells and their impact on tumor surveillance remain unknown. Here, we showed that high glucose induced Warburg effect type of bioenergetic profile in Vγ9Vδ2 T cells, leading to excessive lactate accumulation, which further inhibited lytic granule secretion by impairing the trafficking of cytolytic machinery to the Vγ9Vδ2 T-cell-tumor synapse by suppressing AMPK activation and resulted in the loss of antitumor activity in vitro, in vivo and in patients. Strikingly, activating the AMPK pathway through glucose control or metformin treatment reversed the metabolic abnormalities and restored the antitumor activity of Vγ9Vδ2 T cells. These results suggest that the impaired antitumor activity of Vγ9Vδ2 T cells induced by dysregulated glucose metabolism may contribute to the increased cancer risk in T2DM patients and that metabolic reprogramming by targeting the AMPK pathway with metformin may improve tumor immunosurveillance.


Assuntos
Diabetes Mellitus Tipo 2 , Metformina , Neoplasias , Proteínas Quinases Ativadas por AMP/farmacologia , Glucose , Humanos , Ativação Linfocitária , Metformina/farmacologia , Monitorização Imunológica , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo , Linfócitos T
12.
Cells ; 12(1)2022 12 29.
Artigo em Inglês | MEDLINE | ID: mdl-36611932

RESUMO

Colorectal cancer (CRC) is one of the most frequent tumor entities worldwide with only limited therapeutic options. CRC is not only a genetic disease with several mutations in specific oncogenes and/or tumor suppressor genes such as APC, KRAS, PIC3CA, BRAF, SMAD4 or TP53 but also a multifactorial disease including environmental factors. Cancer cells communicate with their environment mostly via soluble factors such as cytokines, chemokines or growth factors to generate a favorable tumor microenvironment (TME). The TME, a heterogeneous population of differentiated and progenitor cells, plays a critical role in regulating tumor development, growth, invasion, metastasis and therapy resistance. In this context, cytokines from cancer cells and cells of the TME influence each other, eliciting an inflammatory milieu that can either enhance or suppress tumor growth and metastasis. Additionally, several lines of evidence exist that the composition of the microbiota regulates inflammatory processes, controlled by cytokine secretion, that play a role in carcinogenesis and tumor progression. In this review, we discuss the cytokine networks between cancer cells and the TME and microbiome in colorectal cancer and the related treatment strategies, with the goal to discuss cytokine-mediated strategies that could overcome the common therapeutic resistance of CRC tumors.


Assuntos
Neoplasias Colorretais , Citocinas , Humanos , Citocinas/genética , Neoplasias Colorretais/patologia , Oncogenes , Mutação , Quimiocinas/genética , Microambiente Tumoral
13.
Cancers (Basel) ; 13(19)2021 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-34638500

RESUMO

(1) Background: about 10% of Wilms Tumor (WT) patients have a malformation or cancer predisposition syndrome (CPS) with causative germline genetic or epigenetic variants. Knowledge on CPS is essential for genetic counselling. (2) Methods: this retrospective analysis focused on 2927 consecutive patients with WTs registered between 1989 and 2017 in the SIOP/GPOH studies. (3) Results: Genitourinary malformations (GU, N = 66, 2.3%), Beckwith-Wiedemann spectrum (BWS, N = 32, 1.1%), isolated hemihypertrophy (IHH, N = 29, 1.0%), Denys-Drash syndrome (DDS, N = 24, 0.8%) and WAGR syndrome (N = 20, 0.7%) were reported most frequently. Compared to others, these patients were younger at WT diagnosis (median age 24.5 months vs. 39.0 months), had smaller tumors (349.4 mL vs. 487.5 mL), less often metastasis (8.2% vs. 18%), but more often nephroblastomatosis (12.9% vs. 1.9%). WT with IHH was associated with blastemal WT and DDS with stromal subtype. Bilateral WTs were common in WAGR (30%), DDS (29%) and BWS (31%). Chemotherapy induced reduction in tumor volume was poor in DDS (0.4% increase) and favorable in BWS (86.9% reduction). The event-free survival (EFS) of patients with BWS was significantly (p = 0.002) worse than in others. (4) Conclusions: CPS should be considered in WTs with specific clinical features resulting in referral to a geneticist. Their outcome was not always favorable.

14.
Cells ; 10(7)2021 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-34209393

RESUMO

The scope of therapeutic options for the treatment of hepatocellular carcinoma (HCC) has recently been expanded by immunotherapeutic regimens. T cell-based therapies, especially in combination with other treatments have achieved far better outcomes compared to conventional treatments alone. However, there is an emerging body of evidence that eliciting T cell responses in immunotherapeutic approaches is insufficient for favorable outcomes. Immune responses in HCC are frequently attenuated in the tumor microenvironment (TME) or may even support tumor progress. Hence, therapies with immune checkpoint inhibitors or adoptive cell therapies appear to necessitate additional modification of the TME to unlock their full potential. In this review, we focus on immunotherapeutic strategies, underlying molecular mechanisms of CD8 T cell immunity, and causes of treatment failure in HCC of viral and non-viral origin. Furthermore, we provide an overview of TME features in underlying etiologies of HCC patients that mediate therapy resistance to checkpoint inhibition and discuss strategies from the literature concerning current approaches to these challenges.


Assuntos
Carcinoma Hepatocelular/imunologia , Carcinoma Hepatocelular/terapia , Imunoterapia , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/terapia , Linfócitos T/imunologia , Animais , Biomarcadores Tumorais/metabolismo , Humanos , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Vigilância Imunológica/efeitos dos fármacos , Linfócitos T/efeitos dos fármacos
15.
Cell Rep ; 35(9): 109210, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34077737

RESUMO

Natural killer (NK) cells are cytotoxic lymphocytes capable of rapid cytotoxicity, cytokine secretion, and clonal expansion. To sustain such energetically demanding processes, NK cells must increase their metabolic capacity upon activation. However, little is known about the metabolic requirements specific to NK cells in vivo. To gain greater insight, we investigated the role of aerobic glycolysis in NK cell function and demonstrate that their glycolytic rate increases rapidly following viral infection and inflammation, prior to that of CD8+ T cells. NK cell-specific deletion of lactate dehydrogenase A (LDHA) reveals that activated NK cells rely on this enzyme for both effector function and clonal proliferation, with the latter being shared with T cells. As a result, LDHA-deficient NK cells are defective in their anti-viral and anti-tumor protection. These findings suggest that aerobic glycolysis is a hallmark of NK cell activation that is key to their function.


Assuntos
Glicólise , Células Matadoras Naturais/imunologia , Lactato Desidrogenase 5/metabolismo , Muromegalovirus/imunologia , Neoplasias/imunologia , Aerobiose , Animais , Linfócitos T CD8-Positivos/imunologia , Proliferação de Células , Células Clonais , Infecções por Citomegalovirus/imunologia , Infecções por Citomegalovirus/patologia , Infecções por Citomegalovirus/virologia , Homeostase , Camundongos Endogâmicos C57BL , Neoplasias/patologia , Regulação para Cima
16.
Wiley Interdiscip Rev RNA ; 11(2): e1558, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31231984

RESUMO

Protein kinase R (PKR), originally known as an antiviral protein, senses various stresses as well as pathogen-driven double-stranded RNAs. Thereby activated PKR provokes diverse downstream events, including eIF2α phosphorylation and nuclear factor kappa-light-chain-enhancer of activated B cells activation. Consequently, PKR induces apoptosis and inflammation, both of which are highly important in cancer as much as its original antiviral role. Therefore, cellular proteins and RNAs should tightly control PKR activity. PKR and its regulators are often dysregulated in cancer and it is undoubted that such dysregulation contributes to tumorigenesis. However, PKR's precise role in cancer is still in debate, due to incomprehensible and even contradictory data. In this review, we introduce important cellular PKR regulators and discuss about their roles in cancer. Among them, we pay particular attention to nc886, a PKR repressor noncoding RNA that has been identified relatively recently, because its expression pattern in cancer can explain interesting yet obscure oncologic aspects of PKR. Based on nc886 and its regulation of PKR, we have proposed a tumor surveillance model, which reconciles contradictory data about PKR in cancer. This article is categorized under: Regulatory RNAs/RNAi/Riboswitches > Regulatory RNAs RNA Interactions with Proteins and Other Molecules > Protein-RNA Interactions: Functional Implications.


Assuntos
Neoplasias/metabolismo , eIF-2 Quinase/metabolismo , Humanos , Microambiente Tumoral
17.
Curr Pharm Biotechnol ; 21(12): 1176-1185, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32351178

RESUMO

BACKGROUND: In the last decade, there have been accumulating data that the use of medicinal plants could bring additional benefits to the supportive treatment of various diseases. Nigella sativa (N. sativa, family Ranunculaceae) is one of these plants that has attracted considerable interest. The extracts and seeds of N. sativa and its active component thymoquinone have been studied extensively and the results suggest that N. sativa might carry some therapeutic potential for many diseases, including cancer. METHODS: The selection criteria for references were applied through Pubmed with "N. sativa and cancer", "N. sativa and breast cancer", "N. sativa and metastasis", "N. sativa and cytotoxicity of natural killer cells". The pathway analysis was performed using the PANTHER tool by using five randomly selected N. sativa affected genes (Cyclin D1, P53, p21 protein (Cdc42/Rac) activated kinase 1 (PAK1), B-cell lymphoma 2 (Bcl-2) and vascular endothelial growth factor (VEGF)) in order to elucidate further potentially affected signaling pathways. RESULTS: The aim of this review was to summarize studies regarding the effects of N. sativa in cancer generally, with a focus on breast cancer, its anti-metastatic effects, and how N. sativa modulates the cytotoxicity of Natural Killer cells that play a crucial role in tumor surveillance. CONCLUSION: In summary, the data suggest that N. sativa might be used for its anti-cancer and antimetastatic properties and as an immune system activator against cancer.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Benzoquinonas/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Células Matadoras Naturais/efeitos dos fármacos , Nigella sativa/química , Extratos Vegetais/uso terapêutico , Antineoplásicos Fitogênicos/isolamento & purificação , Benzoquinonas/isolamento & purificação , Neoplasias da Mama/imunologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/imunologia , Feminino , Humanos , Células Matadoras Naturais/imunologia , Metástase Neoplásica , Extratos Vegetais/isolamento & purificação , Plantas Medicinais , Sementes/química , Transdução de Sinais
18.
Methods Mol Biol ; 2055: 325-350, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31502159

RESUMO

MHC class I antigen abnormalities have been shown to be one of the major immune escape mechanisms murine and human cancer cells utilize to avoid recognition and destruction by host immune system. This mechanism has clinical relevance, since it is associated with poor prognosis and/or reduced patients' survival in many types of malignant diseases. The recent impressive clinical responses to T cell-based immunotherapies triggered by checkpoint inhibitors have rekindled tumor immunologists and clinical oncologists' interest in the analysis of the human leukocyte antigen (HLA) class I antigen processing machinery (APM) expression and function in malignant cells. Abnormalities in the expression, regulation and/or function of components of this machinery have been associated with the development of resistances to T cell-based immunotherapies. In this review, following the description of the human leukocyte antigen (HLA) class I APM organization and function, the information related to the frequency of defects in HLA class I APM component expression in various types of cancer and the underlying molecular mechanisms is summarized. Then the impact of these defects on clinical response to T cell-based immunotherapies and strategies to revert this immune escape process are discussed.


Assuntos
Antígenos de Histocompatibilidade Classe I/genética , Antígenos de Histocompatibilidade Classe I/metabolismo , Neoplasias/terapia , Linfócitos T/transplante , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Terapia Baseada em Transplante de Células e Tecidos , Regulação Neoplásica da Expressão Gênica , Humanos , Imunoterapia , Neoplasias/genética , Neoplasias/imunologia , Prognóstico , Linfócitos T/imunologia , Evasão Tumoral
19.
Urologe A ; 58(8): 943-952, 2019 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-31175377

RESUMO

Tumor follow-up in patients with non-muscle invasive bladder cancer (NMIBC) is a weighing up between the morbidity associated with invasive diagnostics and the risk of tumor recurrence and especially progression. The risk stratification into low, intermediate, and high-risk tumors enables a risk-adapted follow-up. For individual estimation of the risk of progression and recurrence, risk calculators should be used. Follow-up is still based on cystoscopy, which is recommended lifelong for high and intermediate-risk tumors and for up to 5 tumor-free years for low-risk tumors. Urine cytology has a high sensitivity and specificity for high-risk tumors and is recommended in the follow-up care. There is currently no recommendation for any commercially available urinary marker due to inadequate evidence. For the clarification of synchronous and metachronous tumors of the upper urinary tract computed tomography (CT) urography or alternatively magnetic resonance (MR) urography is recommended.


Assuntos
Assistência ao Convalescente , Biomarcadores Tumorais/urina , Cistoscopia , Neoplasias da Bexiga Urinária/terapia , Cistoscopia/métodos , Humanos , Recidiva Local de Neoplasia/patologia , Urografia
20.
Urologe A ; 58(9): 1093-1106, 2019 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-31399775

RESUMO

Follow-up care of patients with muscle-invasive bladder cancer is subdivided into oncological and functional surveillance. More than 80% of local relapses and distant metastases occur within the first 2 years. Recurrences in the remnant urothelium also occur several years after radical cystectomy. Urinary cytology and a computed tomography (CT) scan of the abdomen and thorax including a urography phase are the standard diagnostics for tumor follow-up. There is no clear evidence for a survival benefit for the detection of asymptomatic vs. symptomatic recurrences. After partial cystectomy or trimodal treatment, there is no established follow-up schedule; however, the relatively high incidence of intravesical recurrences should be considered as there are curative treatment approaches including salvage cystectomy. Functional surveillance, which should be carried out lifelong, encompasses prevention and diagnostics of metabolic complications, urethral/ureteral strictures, problems with the urinary stoma, urinary incontinence, sexual dysfunction and urinary tract infections.


Assuntos
Carcinoma de Células de Transição/patologia , Citodiagnóstico/métodos , Recidiva Local de Neoplasia/patologia , Neoplasias da Bexiga Urinária/patologia , Cistectomia , Seguimentos , Humanos
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