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2.
Mol Cell Endocrinol ; 592: 112296, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38844096

RESUMO

Ovarian cancer (OC) adjusts energy metabolism in favor of its progression and dissemination. Because melatonin (Mel) has antitumor actions, we investigated its impact on energy metabolism and kinase signaling in OC cells (SKOV-3 and CAISMOV-24). Cells were divided into control and Mel-treated groups, in the presence or absence of the antagonist luzindole. There was a decrease in the levels of HIF-1α, G6PDH, GAPDH, PDH, and CS after Mel treatment even in the presence of luzindole in both OC cells. Mel treatment also reduced the activity of OC-related enzymes including PFK-1, G6PDH, LDH, CS, and GS whereas PDH activity was increased. Lactate and glutamine levels dropped after Mel treatment. Mel further promoted a reduction in the concentrations of CREB, JNK, NF-kB, p-38, ERK1/2, AKT, P70S6K, and STAT in both cell lines. Mel reverses Warburg-type metabolism and possibly reduces glutaminolysis, thereby attenuating various oncogenic molecules associated with OC progression and invasion.

3.
Immunol Cell Biol ; 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38873699

RESUMO

Antibiotic resistance is a major public health threat, and alternatives to antibiotic therapy are urgently needed. Immunotherapy, particularly the blockade of inhibitory immune checkpoints, is a leading treatment option in cancer and autoimmunity. In this study, we used a murine model of Salmonella Typhimurium infection to investigate whether immune checkpoint blockade could be applied to bacterial infection. We found that the immune checkpoint T-cell immunoglobulin and ITIM domain (TIGIT) was significantly upregulated on lymphocytes during infection, particularly on CD4+ T cells, drastically limiting their proinflammatory function. Blockade of TIGIT in vivo using monoclonal antibodies was able to enhance immunity and improve bacterial clearance. The efficacy of anti-TIGIT was dependent on the capacity of the antibody to bind to Fc (fragment crystallizable) receptors, giving important insights into the mechanism of anti-TIGIT therapy. This research suggests that targeting immune checkpoints, such as TIGIT, has the potential to enhance immune responses toward bacteria and restore antibacterial treatment options in the face of antibiotic resistance.

4.
Immunol Cell Biol ; 102(6): 444-447, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38693888

RESUMO

Natural killer (NK) cells possess potent cytotoxicity against infected and cancerous cells and hold promise in the development of new immunotherapies. This article for the Highlights of 2023 Series focuses on current advances in NK cell biology in cancerous and infectious settings and highlights opportunities for therapeutic interventions, including engineered NK cell therapies and advancements in feeder cell technologies.


Assuntos
Engenharia Celular , Imunoterapia , Células Matadoras Naturais , Neoplasias , Humanos , Células Matadoras Naturais/imunologia , Imunoterapia/métodos , Neoplasias/terapia , Neoplasias/imunologia , Animais , Citotoxicidade Imunológica , Imunoterapia Adotiva/métodos
5.
EBioMedicine ; 104: 105176, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38810560

RESUMO

BACKGROUND: Natural killer (NK) cells are important innate immunity players and have unique abilities to recognize and eliminate cancer cells, particularly in settings of antibody-opsonization and antibody-dependant cellular cytotoxicity (ADCC). However, NK cell-based responses in bladder cancers to therapeutic antibodies are typically immunosuppressed, and these immunosuppressive mechanisms are largely unknown. METHODS: Single cell RNA sequencing (scRNA-seq) and high-dimensional flow cytometry were used to investigate the phenotype of tumour-infiltrating NK cells in patients with bladder cancer. Further, in vitro, and in vivo models of this disease were used to validate these findings. FINDINGS: NK cells within bladder tumours displayed reduced expression of FcγRIIIa/CD16, the critical Fc receptor involved in ADCC-mediated cytotoxicity, on both transcriptional and protein levels. Transcriptional signatures of transforming growth factor (TGF)-ß-signalling, a pleiotropic cytokine known for its immunosuppressive and tissue residency-inducing effects, were upregulated in tumour-infiltrating NK cells. TGF-ß mediated CD16 downregulation on NK cells, was further validated in vitro, which was accompanied by a transition into a tissue residency phenotype. This CD16 downregulation was also abrogated by TGF-ßR signalling inhibition, which could also restore the ADCC ability of NK cells subject to TGF-ß effects. In a humanized mouse model of bladder cancer, mice treated with a TGF-ß inhibitor exhibited increased ADCC activity compared to mice treated only with antibodies. INTERPRETATION: This study highlights how TGF-ß-rich bladder cancers inhibit NK cell-mediated ADCC by downregulating CD16. TGF-ß inhibition represents new avenues to reverse immunosuppression and enhance the tumoricidal capacity of NK cells in bladder cancer. FUNDING: The Guimaraes Laboratory is funded by a US Department of Defense-Breast Cancer Research Program-Breakthrough Award Level 1 (#BC200025), a grant (#2019485) awarded through the Medical Research Future Fund (MRFF, with the support of the Queensland Children's Hospital Foundation, Microba Life Sciences, Richie's Rainbow Foundation, Translational Research Institute (TRI) and UQ), and a grant (#RSS_2023_085) funded by a Metro South Health Research Support Scheme. J.K.M.W. is funded by a UQ Research Training Program PhD Scholarship and N.O. is funded by a NHMRC Postgraduate Scholarship (#2021932).


Assuntos
Células Matadoras Naturais , Receptores de IgG , Transdução de Sinais , Fator de Crescimento Transformador beta , Neoplasias da Bexiga Urinária , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Neoplasias da Bexiga Urinária/imunologia , Neoplasias da Bexiga Urinária/metabolismo , Humanos , Animais , Camundongos , Fator de Crescimento Transformador beta/metabolismo , Receptores de IgG/metabolismo , Citotoxicidade Celular Dependente de Anticorpos/imunologia , Linhagem Celular Tumoral , Modelos Animais de Doenças , Proteínas Ligadas por GPI/metabolismo , Proteínas Ligadas por GPI/genética , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Regulação Neoplásica da Expressão Gênica , Análise de Célula Única , Feminino
6.
Aesthet Surg J ; 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38470860

RESUMO

BACKGROUND: Polyurethane (PU)-coated breast implants are known for their strong integration into breast tissue and the formation of capsules around them. However, capsular contracture can pose both aesthetic and clinical challenges. OBJECTIVES: To analyze the biological and morphological characteristics of the capsular tissue surrounding PU-coated implants, irrespective of their contracture status, and to assess their potential suitability as a flap in revision breast surgery for capsular contracture. METHODS: A total of 23 tissue samples were harvested from the capsules surrounding PU-coated breast implants in 12 female patients during replacement or revision surgery. We evaluated collagen abundance, cellular and vascular density, inflammation, collagen band types and alignment, synovial metaplasia, capsule thickness, and the expression of inflammatory biomarkers and myofibroblasts using immunohistochemical techniques. Scanning electron microscopy was used to assess implant surface characteristics over time. RESULTS: We found a significant association of capsule contraction with longer implantation durations and greater implant surface roughness (p = 0.018 and p = 0.033, respectively). Synovial metaplasia was significantly more frequent in noncontracted capsules (p = 0.0049). Both capsule types consisted of paucicellular, type I collagen-rich compact fibrous tissue with low vascularization. There was a marked reduction in inflammatory cells within the foreign body granuloma. The expression of inflammatory biomarkers in the capsular tissue was negligible. CONCLUSIONS: Given the reduced levels of inflammatory and vascular components within the dense, fibrous capsular tissue, we consider them to be viable alternatives for use as capsular flaps in revision surgery. This strategy has the potential to mimic the reconstruction achieved with acellular dermal matrix.

7.
Clin Transl Immunology ; 13(3): e1501, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38525380

RESUMO

Objectives: Immunotherapies targeting natural killer (NK) cell receptors have shown promise against leukaemia. Unfortunately, cancer immunosuppressive mechanisms that alter NK cell phenotype prevent such approaches from being successful. The study utilises advanced cytometry to examine how cancer immunosuppressive pathways affect NK cell phenotypic changes in clinical samples. Methods: In this study, we conducted a high-dimensional examination of the cell surface expression of 16 NK cell receptors in paediatric patients with acute myeloid leukaemia and acute lymphoblastic leukaemia, as well as in samples of non-age matched adult peripheral blood (APB) and umbilical cord blood (UCB). An unsupervised analysis was carried out in order to identify NK cell populations present in paediatric leukaemias. Results: We observed that leukaemia NK cells clustered together with UCB NK cells and expressed relatively higher levels of the NKG2A receptor compared to APB NK cells. In addition, CD56dimCD16+CD57- NK cells lacking NKG2A expression were mainly absent in paediatric leukaemia patients. However, CD56br NK cell populations expressing high levels of NKG2A were highly represented in paediatric leukaemia patients. NKG2A expression on leukaemia NK cells was found to be positively correlated with the expression of its ligand, suggesting that the NKG2A-HLA-E interaction may play a role in modifying NK cell responses to leukaemia cells. Conclusion: We provide an in-depth analysis of NK cell populations in paediatric leukaemia patients. These results support the development of immunotherapies targeting immunosuppressive receptors, such as NKG2A, to enhance innate immunity against paediatric leukaemia.

10.
Trends Pharmacol Sci ; 45(2): 134-144, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38212196

RESUMO

Sarcomas are rare and heterogeneous cancers that arise from bone or soft tissue, and are the second most prevalent solid cancer in children and adolescents. Owing to the complex nature of pediatric sarcomas, the development of therapeutics for pediatric sarcoma has seen little progress in the past decades. Existing treatments are largely limited to chemotherapy, radiation, and surgery. Limited knowledge of the sarcoma tumor microenvironment (TME) and of well-defined target antigens in the different subtypes necessitates an alternative investigative approach to improve treatments. Recent advances in spatial omics technologies have enabled a more comprehensive study of the TME in multiple cancers. In this opinion article we discuss advances in our understanding of the TME of some cancers enabled by spatial omics technologies, and we explore how these technologies might advance the development of precision treatments for sarcoma, especially pediatric sarcoma.


Assuntos
Sarcoma , Criança , Adolescente , Humanos , Sarcoma/tratamento farmacológico , Sarcoma/patologia , Microambiente Tumoral
11.
Curr Opin Immunol ; 86: 102409, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38154421

RESUMO

Tumour necrosis factor (TNF) is a primary mediator of inflammatory processes by facilitating cell death, immune cell activation and triggering of inflammation. In the cancer context, research has revealed TNF as a multifaceted cytokine that can be both pro- or anti-tumorigenic depending on what context is observed. We explore the plethora of ways that TNF and its receptors manipulate the functional and phenotypic characteristics in the tumour microenvironment (TME) on both tumour cells and immune cells, promoting either tumour elimination or progression. Here, we discuss the latest cutting-edge TNF-focused biologics currently in clinical translation that modifies the TME to derive greater immune responses and therapeutic outcomes, and further give perspectives on the future of targeting TNF in the context of cancer by emerging technological approaches.


Assuntos
Neoplasias , Microambiente Tumoral , Humanos , Inflamação , Fator de Necrose Tumoral alfa/fisiologia , Citocinas , Neoplasias/terapia
12.
Cell Biosci ; 13(1): 132, 2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37480151

RESUMO

BACKGROUND: Metastatic cancer cells exploit Epithelial-mesenchymal-transition (EMT) to enhance their migration, invasion, and resistance to treatments. Recent studies highlight that elevated levels of copper are implicated in cancer progression and metastasis. Clinical trials using copper chelators are associated with improved patient survival; however, the molecular mechanisms by which copper depletion inhibits tumor progression and metastasis are poorly understood. This remains a major hurdle to the clinical translation of copper chelators. Here, we propose that copper chelation inhibits metastasis by reducing TGF-ß levels and EMT signaling. Given that many drugs targeting TGF-ß have failed in clinical trials, partly because of severe side effects arising in patients, we hypothesized that copper chelation therapy might be a less toxic alternative to target the TGF-ß/EMT axis. RESULTS: Our cytokine array and RNA-seq data suggested a link between copper homeostasis, TGF-ß and EMT process. To validate this hypothesis, we performed single-cell imaging, protein assays, and in vivo studies. Here, we used the copper chelating agent TEPA to block copper trafficking. Our in vivo study showed a reduction of TGF-ß levels and metastasis to the lung in the TNBC mouse model. Mechanistically, TEPA significantly downregulated canonical (TGF-ß/SMAD2&3) and non-canonical (TGF-ß/PI3K/AKT, TGF-ß/RAS/RAF/MEK/ERK, and TGF-ß/WNT/ß-catenin) TGF-ß signaling pathways. Additionally, EMT markers of MMP-9, MMP-14, Vimentin, ß-catenin, ZEB1, and p-SMAD2 were downregulated, and EMT transcription factors of SNAI1, ZEB1, and p-SMAD2 accumulated in the cytoplasm after treatment. CONCLUSIONS: Our study suggests that copper chelation therapy represents a potentially effective therapeutic approach for targeting TGF-ß and inhibiting EMT in a diverse range of cancers.

13.
Nat Commun ; 14(1): 2155, 2023 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-37059710

RESUMO

Acute myeloid leukemia (AML) is a genetically heterogeneous, aggressive hematological malignancy induced by distinct oncogenic driver mutations. The effect of specific AML oncogenes on immune activation or suppression is unclear. Here, we examine immune responses in genetically distinct models of AML and demonstrate that specific AML oncogenes dictate immunogenicity, the quality of immune response and immune escape through immunoediting. Specifically, expression of NrasG12D alone is sufficient to drive a potent anti-leukemia response through increased MHC Class II expression that can be overcome with increased expression of Myc. These data have important implications for the design and implementation of personalized immunotherapies for patients with AML.


Assuntos
Neoplasias Hematológicas , Leucemia Mieloide Aguda , Humanos , Leucemia Mieloide Aguda/patologia , Oncogenes , Neoplasias Hematológicas/genética
14.
Plast Reconstr Surg ; 152(1): 42e-50e, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-36728462

RESUMO

BACKGROUND: Silicone implants have been used to improve volume and body contour in buttocks for almost 45 years. Although the intramuscular plane continues to be the standard, surgeons still diverge on the best incision technique: using a vertical incision, and thus without the preservation of the intergluteal groove, or preserving this area through a triangular dissection. The goal of this research study was to evaluate and compare these techniques of intramuscular augmentation gluteoplasty. METHODS: Two randomized groups were formed with 53 patients in each group. One of the groups underwent intramuscular gluteoplasty with a vertical incision in the intergluteal groove, and therefore without the preservation of said intergluteal groove (group A). In the other group, intramuscular gluteoplasty was performed using a triangular dissection, thus preserving the intergluteal groove (group B). The groups were compared in relation to the incidence of complications (ie, dehiscence, hematoma, seroma, and infection). RESULTS: A total of 7.5% of patients in group A presented dehiscence and 1.9% presented seroma. In group B, however, 28.3% of patients presented dehiscence and 7.5% presented seroma and dehiscence during the first 21 days after surgery. No patient had hematoma or infection in either group. CONCLUSION: In the comparison between the groups of patients, the technique with a vertical incision in the intergluteal groove showed a lower number of surgical wounds, dehiscences, and seromas when compared with the technique that preserves the intergluteal groove. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, II.


Assuntos
Procedimentos de Cirurgia Plástica , Ferida Cirúrgica , Humanos , Nádegas/cirurgia , Próteses e Implantes , Seroma/epidemiologia , Seroma/etiologia , Ferida Cirúrgica/cirurgia
15.
Trends Biotechnol ; 41(1): 77-92, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35840426

RESUMO

Natural killer (NK) cells have emerged as a major target for cancer immunotherapies, particularly as cellular therapy modalities because they have relatively less toxicity than T lymphocytes. However, NK cell-based therapy suffers from many challenges, including problems with its activation, resistance to genetic engineering, and large-scale expansion needed for therapeutic purposes. Recently, nanobiomaterials have emerged as a promising solution to control the challenges associated with NK cells. This focused review summarises the recent advances in the field and highlights current and future perspectives of using nanobiomaterials to maximise anticancer responses of NK cells for safe and effective immunotherapy. Finally, we provide our opinion on the role of smart materials in activating NK cells as a potential cellular therapy of the future.


Assuntos
Neoplasias , Humanos , Neoplasias/terapia , Células Matadoras Naturais , Imunoterapia , Linfócitos T , Imunoterapia Adotiva
16.
Cell Mol Immunol ; 20(1): 65-79, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36471114

RESUMO

The cytokine granulocyte-macrophage-colony stimulating factor (GM-CSF) possesses the capacity to differentiate monocytes into macrophages (MØs) with opposing functions, namely, proinflammatory M1-like MØs and immunosuppressive M2-like MØs. Despite the importance of these opposing biological outcomes, the intrinsic mechanism that regulates the functional polarization of MØs under GM-CSF signaling remains elusive. Here, we showed that GM-CSF-induced MØ polarization resulted in the expression of cytokine-inducible SH2-containing protein (CIS) and that CIS deficiency skewed the differentiation of monocytes toward immunosuppressive M2-like MØs. CIS deficiency resulted in hyperactivation of the JAK-STAT5 signaling pathway, consequently promoting downregulation of the transcription factor Interferon Regulatory Factor 8 (IRF8). Loss- and gain-of-function approaches highlighted IRF8 as a critical regulator of the M1-like polarization program. In vivo, CIS deficiency induced the differentiation of M2-like macrophages, which promoted strong Th2 immune responses characterized by the development of severe experimental asthma. Collectively, our results reveal a CIS-modulated mechanism that clarifies the opposing actions of GM-CSF in MØ differentiation and uncovers the role of GM-CSF in controlling allergic inflammation.


Assuntos
Fator Estimulador de Colônias de Granulócitos e Macrófagos , Macrófagos , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Monócitos/metabolismo , Citocinas/metabolismo , Fatores Reguladores de Interferon/metabolismo , Diferenciação Celular
17.
Trends Cancer ; 9(2): 111-121, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36379852

RESUMO

Enhancing natural killer (NK) cell-based innate immunity has become a promising strategy for immunotherapy against hard-to-cure solid cancers. Monoclonal antibody (mAb) therapy has been used to activate NK-cell-mediated antibody-dependent cellular cytotoxicity (ADCC) towards solid cancers. Cancer cells, however, can subvert immunosurveillance using multiple immunosuppressive mechanisms, which may hamper NK cell ADCC. Mechanisms to safely enhance ADCC by NK cells, such as utilizing temporary inhibition of receptor endocytosis to increase antibody presentation from target to effector cells can now be used to enhance NK-cell-mediated ADCC against solid tumors. This review summarizes and discusses the recent advances in the field and highlights current and potential future use of immunotherapies to maximize the therapeutic efficacy of innate anticancer immunity.


Assuntos
Células Matadoras Naturais , Neoplasias , Humanos , Citotoxicidade Celular Dependente de Anticorpos , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/uso terapêutico , Neoplasias/tratamento farmacológico , Imunoterapia
18.
Cureus ; 15(12): e50007, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38186457

RESUMO

Leprosy, or Hansen's disease, mistakenly considered a disease from the past by some, is still common nowadays, especially in tropical and subtropical regions. In the absence of appropriate medical treatment, it may progress and cause permanent damage to multiple organs. This case report illustrates the diagnostic challenge of a south-american adult man who had been living in Europe for over 14 years. He was referred to the Hematology department due to persistent lymphocytosis and a CD5+ B-cell lymphoproliferative disorder was identified. During clinical surveillance, the patient developed skin lesions in his limbs with associated hypoesthesia. A histological diagnosis of lepromatous leprosy was made, and he underwent a long-term three-drug therapeutic regimen (dapsone, rifampicin, and clofazimine). Adding to the complexity of the case, the patient progressed with splenomegaly and constitutional symptoms, more than 7 years after development of lymphocytosis. Through a comprehensive evaluation, a definitive diagnosis of mantle cell lymphoma was established and received 6-cycle R-CHOP induction, followed by maintenance rituximab. Importantly, prophylaxis for leprosy reactivation was not administered as there were no recommendations in available guidelines. Eventually, the patient experienced a leprosy relapse while on maintenance therapy, 58 months after completing the initial anti-leprous treatment. Clinical response was attained with a new treatment regimen consisting of rifampicin, clofazimine, and minocycline.  Although leprosy is primarily observed in tropical and subtropical regions, the long incubation period of this disease combined with the global flow of migrants, made us consider it. Despite being rare, leprosy relapses can occur even after a few decades. The contribution of rituximab or previously administered chemotherapeutic agents is still unknown. The question remains whether antibiotic prophylaxis should be performed in patients undergoing immunochemotherapy for malignant diseases.

19.
Trends Immunol ; 43(11): 864-867, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36244891

RESUMO

Recent evidence suggests that cancer cell-derived extracellular vesicles might facilitate immunoevasion. Glycans are known to play a key role in immunomodulation, especially when tethered to biological membranes. However, the extracellular vesicle glycocode in cancer immunoevasion remains a largely unexplored area with promising potential for new putative diagnostic and therapeutic applications.


Assuntos
Vesículas Extracelulares , Neoplasias , Humanos , Neoplasias/terapia
20.
Cancers (Basel) ; 14(20)2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-36291837

RESUMO

Neoadjuvant chemotherapy (NACT) is offered to patients with operable or inoperable breast cancer (BC) to downstage the disease. Clinical responses to NACT may vary depending on a few known clinical and biological features, but the diversity of responses to NACT is not fully understood. In this study, 80 women had their metabolite profiles of pre-treatment sera analyzed for potential NACT response biomarker candidates in combination with immunohistochemical parameters using Nuclear Magnetic Resonance (NMR). Sixty-four percent of the patients were resistant to chemotherapy. NMR, hormonal receptors (HR), human epidermal growth factor receptor 2 (HER2), and the nuclear protein Ki67 were combined through machine learning (ML) to predict the response to NACT. Metabolites such as leucine, formate, valine, and proline, along with hormone receptor status, were discriminants of response to NACT. The glyoxylate and dicarboxylate metabolism was found to be involved in the resistance to NACT. We obtained an accuracy in excess of 80% for the prediction of response to NACT combining metabolomic and tumor profile data. Our results suggest that NMR data can substantially enhance the prediction of response to NACT when used in combination with already known response prediction factors.

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