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1.
Cancer Res ; 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38657099

RESUMO

Extranodal NK/T-cell lymphoma (ENKTCL) is an Epstein-Barr virus (EBV)-related neoplasm with male dominance and a poor prognosis. A better understanding of the genetic alterations and their functional roles in ENKTCL could help improve patient stratification and treatments. Here, we performed comprehensive genetic analysis of 177 ENKTCL cases to delineate the landscape of mutations, copy number alterations (CNAs), and structural variations, identifying 34 driver genes including six previously unappreciated ones, namely HLA-B, HLA-C, ROBO1, CD58, POT1, and MAP2K1. Among them, CD274 (24%) was the most frequently altered, followed by TP53 (20%), CDKN2A (19%), ARID1A (15%), HLA-A (15%), BCOR (14%), and MSN (14%). Chromosome X (chrX) losses were the most common arm-level CNAs in females (~40%), and alterations of four X-linked driver genes (MSN, BCOR, DDX3X, and KDM6A) were more frequent in males and females harboring chrX losses. Among X-linked drivers, MSN was the most recurrently altered, and its expression was lost in approximately one-third of cases using immunohistochemical analysis. Functional studies of human cell lines demonstrated that MSN disruption promoted cell proliferation and NF-κB activation. Moreover, MSN inactivation increased sensitivity to NF-κB inhibition in vitro and in vivo. In addition, recurrent deletions were observed at the origin of replication in the EBV genome (6%). Finally, by integrating the 34 drivers and 19 significant arm-level CNAs, non-negative matrix factorization and consensus clustering identified two molecular groups with different genetic features and prognosis irrespective of clinical prognostic factors. Together, these findings could help improve diagnostic and therapeutic strategies in ENKTCL.

2.
Appl Opt ; 62(15): 3989-3999, 2023 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-37706710

RESUMO

Multispectral quantitative phase imaging (MS-QPI) is a high-contrast label-free technique for morphological imaging of the specimens. The aim of the present study is to extract spectral dependent quantitative information in single-shot using a highly spatially sensitive digital holographic microscope assisted by a deep neural network. There are three different wavelengths used in our method: λ=532, 633, and 808 nm. The first step is to get the interferometric data for each wavelength. The acquired datasets are used to train a generative adversarial network to generate multispectral (MS) quantitative phase maps from a single input interferogram. The network was trained and validated on two different samples: the optical waveguide and MG63 osteosarcoma cells. Validation of the present approach is performed by comparing the predicted MS phase maps with numerically reconstructed (F T+T I E) phase maps and quantifying with different image quality assessment metrices.


Assuntos
Aprendizado Profundo , Holografia , Interferometria , Redes Neurais de Computação
3.
Langmuir ; 39(19): 6691-6697, 2023 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-37129583

RESUMO

A wide variety of cues from the extracellular matrix (ECM) have been known to affect the differentiation of stem cells in vivo. In particular, the biophysical cues and cell shape have been known to affect the stem cell function, yet very little is known about the interplay between how these cues control differentiation. For the first time, by using photolithography to pattern poly(ethylene glycol) (PEG), patterns of square and triangular geometries were created, and the effect of these structures and the biophysical cues arising were utilized to differentiate cells into multiple lineages inside a same pattern without the use of any adhered protein or growth factors. The data from these studies showed that the cells present at the edges were well elongated, exhibit high aspect ratios, and differentiated into osteogenic lineage, whereas the cells present at the center exhibit lower aspect ratio and were primarily adipogenic lineage regardless of the geometry. This was correlated to the higher expression of focal adhesion proteins at the edges, the expression of which have been known to affect the osteogenic differentiation. By showing MSC lineage commitment relationships due to physical signals, this study highlights the importance of these cues and cell shape in further understanding stem cell behavior for tissue engineering applications.


Assuntos
Células-Tronco Mesenquimais , Osteogênese , Sinais (Psicologia) , Diferenciação Celular , Células-Tronco , Matriz Extracelular/metabolismo
4.
Front Immunol ; 13: 956919, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35874778

RESUMO

Allogeneic hematopoietic stem cell transplantation (HSCT) is the treatment of preference for numerous malignant and non-malignant hemopathies. The outcome of this approach is significantly hampered by not only graft-versus-host disease (GvHD), but also infections and relapses that may occur because of persistent T-cell immunodeficiency following transplantation. Reconstitution of a functional T-cell repertoire can take more than 1 year. Thus, the major challenge in the management of allogeneic HSCT relies on the possibility of shortening the window of immune deficiency through the acceleration of T-cell recovery, with diverse, self-tolerant, and naïve T cells resulting from de novo thymopoiesis from the donor cells. In this context, adoptive transfer of cell populations that can give rise to mature T cells faster than HSCs while maintaining a safety profile compatible with clinical use is of major interest. In this review, we summarize current advances in the characterization of thymus seeding progenitors, and their ex vivo generated counterparts, T-cell progenitors. Transplantation of the latter has been identified as a worthwhile approach to shorten the period of immune deficiency in patients following allogeneic HSCT, and to fulfill the clinical objective of reducing morbimortality due to infections and relapses. We further discuss current opportunities for T-cell progenitor-based therapy manufacturing, including iPSC cell sources and off-the-shelf strategies. These opportunities will be analyzed in the light of results from ongoing clinical studies involving T-cell progenitors.


Assuntos
Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Transferência Adotiva , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Transplante de Células-Tronco Hematopoéticas/métodos , Humanos , Recidiva , Linfócitos T
5.
ACS Appl Bio Mater ; 5(6): 2870-2879, 2022 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-35679315

RESUMO

Designing smart bioinks, which can provide multifunctionality and instructive cues to cells, is a current need of the tissue engineering field. Addressing these parameters, this work aims at developing a smart dual 3D bioprinted scaffold that is capable of differentiating human mesenchymal stem cells into two different lineages within the same construct without providing any exogenous cues. Here, biocompatible alginate- and silk-based bioinks were developed to print self-standing structures with the ability of spatially controlled differentiation of the encapsulated hMSCs. We present this proof of concept and have demonstrated a smart design where the incorporation of phosphate groups enhanced the osteogenic differentiation, whereas the addition of silk promoted the chondrogenic differentiation. Altogether, the present work suggests the potential of the developed bioinks for use in creating clinically viable osteochondral grafts.


Assuntos
Bioimpressão , Células-Tronco Mesenquimais , Alginatos/farmacologia , Humanos , Osteogênese , Seda/química
6.
Mater Sci Eng C Mater Biol Appl ; 128: 112344, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34474894

RESUMO

A micron scale alginate based 3D platform embedded with a carbon dot pH sensor, that enables continuous growth monitoring of encapsulated cells in real time is reported. The alginate based 3D micro-scaffold closely mimics a tumor microenvironment by providing a spatial demarcation and making it possible to encapsulate different cells in close proximity. The micro-scaffold contains carbon dot based nanosensors that enable real time monitoring of pH change in the tumor microenvironment avoiding the need for end-point assays for studying cellular growth. The micro-scaffolds have heterogeneous architecture and a hypoxic core region can be observed in as less as 96 h of culture. In this completely synthetic platform, there also exist the flexibility of artificially modifying the porosity of the micro-scaffold as per the requirement of the studies where a denser ECM mimic is required. The micro-scaffolds were conducive for cell growth as suggested by the enhanced functional profile of hepatocellular carcinoma cells and positively influence the genetic expression of the cell specific markers. Additionally, similar to a 3D tumor, non-homogeneous diffusion of molecules is also observed making this an ideal platform for cancer modelling and drug screening.


Assuntos
Alginatos , Neoplasias , Técnicas de Cultura de Células , Proliferação de Células , Humanos , Porosidade , Alicerces Teciduais , Microambiente Tumoral
7.
Cell Mol Immunol ; 18(7): 1662-1676, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34117371

RESUMO

Several obstacles to the production, expansion and genetic modification of immunotherapeutic T cells in vitro have restricted the widespread use of T-cell immunotherapy. In the context of HSCT, delayed naïve T-cell recovery contributes to poor outcomes. A novel approach to overcome the major limitations of both T-cell immunotherapy and HSCT would be to transplant human T-lymphoid progenitors (HTLPs), allowing reconstitution of a fully functional naïve T-cell pool in the patient thymus. However, it is challenging to produce HTLPs in the high numbers required to meet clinical needs. Here, we found that adding tumor necrosis factor alpha (TNFα) to a DL-4-based culture system led to the generation of a large number of nonmodified or genetically modified HTLPs possessing highly efficient in vitro and in vivo T-cell potential from either CB HSPCs or mPB HSPCs through accelerated T-cell differentiation and enhanced HTLP cell cycling and survival. This study provides a clinically suitable cell culture platform to generate high numbers of clinically potent nonmodified or genetically modified HTLPs for accelerating immune recovery after HSCT and for T-cell-based immunotherapy (including CAR T-cell therapy).


Assuntos
Transplante de Células-Tronco Hematopoéticas , Fator de Necrose Tumoral alfa , Técnicas de Cultura de Células , Diferenciação Celular , Humanos , Imunoterapia , Linfócitos T
8.
Acta Biomater ; 121: 579-591, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33285325

RESUMO

Nanoparticles with longer blood circulation, high loading capacity, controlled release at the targeted site, and preservation of camptothecin (CPT) in its lactone form are the key characteristics for the effective delivery of CPT. In this regard, natural membrane-derived nanovesicles, particularly those derived from RBC membrane, are important. RBC membrane can be engineered to form vesicles or can be coated over synthetic nanoparticles, without losing their basic structural features and can have prolonged circulation time. Here, we developed a hybrid system to encapsulate CPT inside the amphiphilic micelle and coat it with RBC membrane. Thus, it uses the dual ability of polymeric micelles to preserve CPT in its active form, while maintaining its "stealth" effect due to conserved RBC membrane coating. The hybrid system stabilized 60% of the drug in its active form even after 30 h of incubation in serum, in contrast to 15% active form present in free drug formulation after 1 h of incubation. It showed strong retention inside the Ehrlich Ascites Carcinoma (EAC) mice models for at least 72 h, suggesting camouflaging ability conferred by RBC membrane. Additionally, the nano formulation retarded the tumor growth rate more efficiently than free drug, with no evident signs of necrotic skin lesions. Histopathological analysis showed a significant reduction in cardiac atrophy, hepato-renal degeneration, and lung metastasis, which resulted in the increased overall survival of mice treated with the nano formulation. Hence, CPT-loaded polymeric micelles when coated with RBC membrane can prove to be a better system for the delivery of poorly soluble drug camptothecin.


Assuntos
Camptotecina , Nanopartículas , Animais , Camptotecina/farmacologia , Camundongos , Micelas , Polímeros , Inibidores da Topoisomerase
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