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1.
World J Stem Cells ; 16(5): 551-559, 2024 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-38817332

RESUMEN

BACKGROUND: Embryonic stem cells (ESCs) serve as a crucial ex vivo model, representing epiblast cells derived from the inner cell mass of blastocyst-stage embryos. ESCs exhibit a unique combination of self-renewal potency, unlimited proliferation, and pluripotency. The latter is evident by the ability of the isolated cells to differentiate spontaneously into multiple cell lineages, representing the three primary embryonic germ layers. Multiple regulatory networks guide ESCs, directing their self-renewal and lineage-specific differentiation. Apoptosis, or programmed cell death, emerges as a key event involved in sculpting and forming various organs and structures ensuring proper embryonic development. However, the molecular mechanisms underlying the dynamic interplay between differentiation and apoptosis remain poorly understood. AIM: To investigate the regulatory impact of apoptosis on the early differentiation of ESCs into cardiac cells, using mouse ESC (mESC) models - mESC-B-cell lymphoma 2 (BCL-2), mESC-PIM-2, and mESC-metallothionein-1 (MET-1) - which overexpress the anti-apoptotic genes Bcl-2, Pim-2, and Met-1, respectively. METHODS: mESC-T2 (wild-type), mESC-BCL-2, mESC-PIM-2, and mESC-MET-1 have been used to assess the effect of potentiated apoptotic signals on cardiac differentiation. The hanging drop method was adopted to generate embryoid bodies (EBs) and induce terminal differentiation of mESCs. The size of the generated EBs was measured in each condition compared to the wild type. At the functional level, the percentage of cardiac differentiation was measured by calculating the number of beating cardiomyocytes in the manipulated mESCs compared to the control. At the molecular level, quantitative reverse transcription-polymerase chain reaction was used to assess the mRNA expression of three cardiac markers: Troponin T, GATA4, and NKX2.5. Additionally, troponin T protein expression was evaluated through immunofluorescence and western blot assays. RESULTS: Our findings showed that the upregulation of Bcl-2, Pim-2, and Met-1 genes led to a reduction in the size of the EBs derived from the manipulated mESCs, in comparison with their wild-type counterpart. Additionally, a decrease in the count of beating cardiomyocytes among differentiated cells was observed. Furthermore, the mRNA expression of three cardiac markers - troponin T, GATA4, and NKX2.5 - was diminished in mESCs overexpressing the three anti-apoptotic genes compared to the control cell line. Moreover, the overexpression of the anti-apoptotic genes resulted in a reduction in troponin T protein expression. CONCLUSION: Our findings revealed that the upregulation of Bcl-2, Pim-2, and Met-1 genes altered cardiac differentiation, providing insight into the intricate interplay between apoptosis and ESC fate determination.

2.
Front Immunol ; 15: 1324093, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38361928

RESUMEN

Pancreatic adenocarcinoma (PDAC) is an aggressive tumor with poor survival and limited treatment options. PDAC resistance to immunotherapeutic strategies is multifactorial, but partially owed to an immunosuppressive tumor immune microenvironment (TiME). However, the PDAC TiME is heterogeneous and harbors favorable tumor-infiltrating lymphocyte (TIL) populations. Tertiary lymphoid structures (TLS) are organized aggregates of immune cells that develop within non-lymphoid tissue under chronic inflammation in multiple contexts, including cancers. Our current understanding of their role within the PDAC TiME remains limited; TLS are complex structures with multiple anatomic features such as location, density, and maturity that may impact clinical outcomes such as survival and therapy response in PDAC. Similarly, our understanding of methods to manipulate TLS is an actively developing field of research. TLS may function as anti-tumoral immune niches that can be leveraged as a therapeutic strategy to potentiate both existing chemotherapeutic regimens and potentiate future immune-based therapeutic strategies to improve patient outcomes. This review seeks to cover anatomy, relevant features, immune effects, translational significance, and future directions of understanding TLS within the context of PDAC.


Asunto(s)
Adenocarcinoma , Neoplasias Pancreáticas , Estructuras Linfoides Terciarias , Humanos , Neoplasias Pancreáticas/patología , Oncología Médica , Microambiente Tumoral
3.
Front Oncol ; 13: 1274783, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38074633

RESUMEN

Introduction: Pancreatic adenocarcinoma (PDAC) is an aggressive tumor with limited response to both chemotherapy and immunotherapy. Pre-treatment tumor features within the tumor immune microenvironment (TiME) may influence treatment response. We hypothesized that the pre-treatment TiME composition differs between metastatic and primary lesions and would be associated with response to modified FOLFIRINOX (mFFX) or gemcitabine-based (Gem-based) therapy. Methods: Using RNAseq data from a cohort of treatment-naïve, advanced PDAC patients in the COMPASS trial, differential gene expression analysis of key immunomodulatory genes in were analyzed based on multiple parameters including tumor site, response to mFFX, and response to Gem-based treatment. The relative proportions of immune cell infiltration were defined using CIBERSORTx and Dirichlet regression. Results: 145 samples were included in the analysis; 83 received mFFX, 62 received Gem-based therapy. Metastatic liver samples had both increased macrophage (1.2 times more, p < 0.05) and increased eosinophil infiltration (1.4 times more, p < 0.05) compared to primary lesion samples. Further analysis of the specific macrophage phenotypes revealed an increased M2 macrophage fraction in the liver samples. The pre-treatment CD8 T-cell, dendritic cell, and neutrophil infiltration of metastatic samples were associated with therapy response to mFFX (p < 0.05), while mast cell infiltration was associated with response to Gem-based therapy (p < 0.05). Multiple immunoinhibitory genes such as ADORA2A, CSF1R, KDR/VEGFR2, LAG3, PDCD1LG2, and TGFB1 and immunostimulatory genes including C10orf54, CXCL12, and TNFSF14/LIGHT were significantly associated with worse survival in patients who received mFFX (p = 0.01). There were no immunomodulatory genes associated with survival in the Gem-based cohort. Discussion: Our evidence implies that essential differences in the PDAC TiME exist between primary and metastatic tumors and an inflamed pretreatment TiME is associated with mFFX response. Defining components of the PDAC TiME that influence therapy response will provide opportunities for targeted therapeutic strategies that may need to be accounted for in designing personalized therapy to improve outcomes.

4.
Sensors (Basel) ; 23(16)2023 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-37631575

RESUMEN

With the proliferation of IoT devices, ensuring the security and privacy of these devices and their associated data has become a critical challenge. In this paper, we propose a federated sampling and lightweight intrusion-detection system for IoT networks that use K-meansfor sampling network traffic and identifying anomalies in a semi-supervised way. The system is designed to preserve data privacy by performing local clustering on each device and sharing only summary statistics with a central aggregator. The proposed system is particularly suitable for resource-constrained IoT devices such as sensors with limited computational and storage capabilities. We evaluate the system's performance using the publicly available NSL-KDD dataset. Our experiments and simulations demonstrate the effectiveness and efficiency of the proposed intrusion-detection system, highlighting the trade-offs between precision and recall when sharing statistics between workers and the coordinator. Notably, our experiments show that the proposed federated IDS can increase the true-positive rate up to 10% when the workers and the coordinator collaborate.

5.
JCI Insight ; 8(6)2023 03 22.
Artículo en Inglés | MEDLINE | ID: mdl-36749632

RESUMEN

We assessed vaccine-induced antibody responses to the SARS-CoV-2 ancestral virus and Omicron variant before and after booster immunization in 57 patients with B cell malignancies. Over one-third of vaccinated patients at the pre-booster time point were seronegative, and these patients were predominantly on active cancer therapies such as anti-CD20 monoclonal antibody. While booster immunization was able to induce detectable antibodies in a small fraction of seronegative patients, the overall booster benefit was disproportionately evident in patients already seropositive and not receiving active therapy. While ancestral virus- and Omicron variant-reactive antibody levels among individual patients were largely concordant, neutralizing antibodies against Omicron tended to be reduced. Interestingly, in all patients, including those unable to generate detectable antibodies against SARS-CoV-2 spike, we observed comparable levels of EBV- and influenza-reactive antibodies, demonstrating that B cell-targeting therapies primarily impair de novo but not preexisting antibody levels. These findings support rationale for vaccination before cancer treatment.


Asunto(s)
COVID-19 , Neoplasias , Humanos , Vacunas contra la COVID-19 , Formación de Anticuerpos , SARS-CoV-2 , Neoplasias/terapia , Anticuerpos Monoclonales , Anticuerpos Antivirales
6.
Cancer Discov ; 12(5): 1184-1186, 2022 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-35491648

RESUMEN

Dose-limiting toxicities are thought to temper the efficacy of single-agent 4-1BB agonists. To overcome this hurdle, in this issue of Cancer Discovery, Muik and colleagues report preclinical and clinical studies describing a first-in-class bispecific fusion protein targeting 4-1BB and PD-L1. See related article by Muik et al., p. 1248 (9).


Asunto(s)
Anticuerpos Biespecíficos , Neoplasias , Antígeno B7-H1/genética , Humanos , Inmunoterapia , Neoplasias/tratamiento farmacológico , Neoplasias/genética
7.
J Immunol ; 208(6): 1362-1370, 2022 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-35228263

RESUMEN

The oncotherapeutic promise of IL-15, a potent immunostimulant, is limited by a short serum t 1/2 The fusion protein N-803 is a chimeric IL-15 superagonist that has a >20-fold longer in vivo t 1/2 versus IL-15. This phase 1 study characterized the pharmacokinetic (PK) profile and safety of N-803 after s.c. administration to healthy human volunteers. Volunteers received two doses of N-803, and after each dose, PK and safety were assessed for 9 d. The primary endpoint was the N-803 PK profile, the secondary endpoint was safety, and immune cell levels and immunogenicity were measures of interest. Serum N-803 concentrations peaked 4 h after administration and declined with a t 1/2 of ∼20 h. N-803 did not cause treatment-emergent serious adverse events (AEs) or grade ≥3 AEs. Injection site reactions, chills, and pyrexia were the most common AEs. Administration of N-803 was well tolerated and accompanied by proliferation of NK cells and CD8+ T cells and sustained increases in the number of NK cells. Our results suggest that N-803 administration can potentiate antitumor immunity.


Asunto(s)
Linfocitos T CD8-positivos , Interleucina-15 , Voluntarios Sanos , Humanos , Proteínas Recombinantes de Fusión
8.
Int J Mol Sci ; 22(14)2021 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-34299287

RESUMEN

Organoids represent one of the most important advancements in the field of stem cells during the past decade. They are three-dimensional in vitro culturing models that originate from self-organizing stem cells and can mimic the in vivo structural and functional specificities of body organs. Organoids have been established from multiple adult tissues as well as pluripotent stem cells and have recently become a powerful tool for studying development and diseases in vitro, drug screening, and host-microbe interaction. The use of stem cells-that have self-renewal capacity to proliferate and differentiate into specialized cell types-for organoids culturing represents a major advancement in biomedical research. Indeed, this new technology has a great potential to be used in a multitude of fields, including cancer research, hereditary and infectious diseases. Nevertheless, organoid culturing is still rife with many challenges, not limited to being costly and time consuming, having variable rates of efficiency in generation and maintenance, genetic stability, and clinical applications. In this review, we aim to provide a synopsis of pluripotent stem cell-derived organoids and their use for disease modeling and other clinical applications.


Asunto(s)
Evaluación Preclínica de Medicamentos/métodos , Técnicas de Cultivo de Órganos/métodos , Organoides/citología , Células Madre Pluripotentes/citología , Animales , Humanos , Modelos Biológicos , Organoides/efectos de los fármacos , Organoides/metabolismo , Células Madre Pluripotentes/efectos de los fármacos , Células Madre Pluripotentes/metabolismo
9.
Front Genet ; 12: 652747, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33841508

RESUMEN

Prostate cancer (PCa) is by far the most commonly diagnosed cancer in men worldwide. Despite sensitivity to androgen deprivation, patients with advanced disease eventually develop resistance to therapy and may die of metastatic castration-resistant prostate cancer (mCRPC). A key challenge in the management of PCa is the clinical heterogeneity that is hard to predict using existing biomarkers. Defining molecular biomarkers for PCa that can reliably aid in diagnosis and distinguishing patients who require aggressive therapy from those who should avoid overtreatment is a significant unmet need. Mechanisms underlying the development of PCa are not confined to cancer epithelial cells, but also involve the tumor microenvironment. The crosstalk between epithelial cells and stroma in PCa has been shown to play an integral role in disease progression and metastasis. A number of key markers of reactive stroma has been identified including stem/progenitor cell markers, stromal-derived mediators of inflammation, regulators of angiogenesis, connective tissue growth factors, wingless homologs (Wnts), and integrins. Here, we provide a synopsis of the stromal-epithelial crosstalk in PCa focusing on the relevant molecular biomarkers pertaining to the tumor microenvironment and their role in diagnosis, prognosis, and therapy development.

10.
SN Compr Clin Med ; 2(11): 2005-2014, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33015555

RESUMEN

Coronavirus disease 2019 (COVID-19) has infected millions of people worldwide and emerged to be the biggest global health threat claiming hundreds of thousands of lives at exponential rates. The severity of the disease increases with old age and presence of underlying health conditions, such as cancer. Managing cancer patients under these circumstances is rather challenging, given their compromised immunity and the overwhelmed health care services by COVID-19 community transmission. Thus, it is prudent to establish common guidelines for the monitoring and treatment of cancer patients. In this review, we comprehensively investigate the various aspects of cancer care during the COVID-19 pandemic, discuss challenges faced while treating cancer patients, and propose potential approaches to manage COVID-19 among this vulnerable population. We also discuss molecular aberrations and genetic changes associated with cancer and their role in affecting the virus' infectivity and severity. Lastly, we shed light on therapeutic approaches that can encompass both diseases without compromising one over the other.

11.
Cells ; 9(10)2020 10 20.
Artículo en Inglés | MEDLINE | ID: mdl-33092038

RESUMEN

Adipose tissue is contemplated as a dynamic organ that plays key roles in the human body. Adipogenesis is the process by which adipocytes develop from adipose-derived stem cells to form the adipose tissue. Adipose-derived stem cells' differentiation serves well beyond the simple goal of producing new adipocytes. Indeed, with the current immense biotechnological advances, the most critical role of adipose-derived stem cells remains their tremendous potential in the field of regenerative medicine. This review focuses on examining the physiological importance of adipogenesis, the current approaches that are employed to model this tightly controlled phenomenon, and the crucial role of adipogenesis in elucidating the pathophysiology and potential treatment modalities of human diseases. The future of adipogenesis is centered around its crucial role in regenerative and personalized medicine.


Asunto(s)
Adipogénesis , Modelos Biológicos , Adipocitos/citología , Animales , Ensayos Clínicos como Asunto , Humanos , Organoides/metabolismo , Células Madre/metabolismo
12.
Placenta ; 90: 90-97, 2020 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-32056558

RESUMEN

INTRODUCTION: The placenta is a transitory organ essential for proper fetal maturation and growth. Trophoblasts, the main cell type of the placenta, differentiate along the villous or extravillous pathways. The ability of villous cytotrophoblasts to undergo an epithelial-to-mesenchymal transition to form the invasive extravillous trophoblasts is vital for a successful pregnancy outcome. Many trophoblastic cell lines, including HTR-8/SVneo, have been widely used to investigate extravillous trophoblast biology and functions. We have previously reported that HTR-8/SVneo cell line contains a mixed populations of epithelial and mesenchymal cells. Uncovering the mechanisms underlying this heterogeneity is essential for the proper study of normal and pathological placental function. METHODS: HTR-8/SVneo was subjected to monoclonal isolation, spheroid formation assay and cell sorting to isolate pure epithelial and mesenchymal populations. These fractions were maintained in culture and assessed for expression of epithelial and mesenchymal markers using quantitative real-time PCR and immunofluorescence. In addition, the implication of TGFß in the EMT process was investigated using a selective inhibitor of TGF-ßR1 (A83-01). RESULTS: Passaging of the pure epithelial population maintained under normal culture condition resulted in a shift to a mesenchymal phenotype. This transition was reduced upon inhibiting TGF-ßR1. Similarly, E-cadherin positive HTR-8/SVneo spheroids plated in 2D culture resulted in the emergence of streams of invading mesenchymal cells. DISCUSSION: HTR-8/SVneo cell line is undergoing EMT under normal culture condition and TGFß is a key mediator of this process. Our results raise the possibility of using HTR-8/SVneo cell line as a model to investigate EMT in extravillous trophoblast cells.


Asunto(s)
Transición Epitelial-Mesenquimal/fisiología , Placenta/citología , Trofoblastos/citología , Cadherinas/metabolismo , Línea Celular , Femenino , Humanos , Placenta/metabolismo , Embarazo , Trofoblastos/metabolismo
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