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1.
Cancer Cell ; 41(5): 903-918.e8, 2023 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-36963399

RESUMO

Esophageal squamous-cell carcinoma (ESCC) develops through multistage epithelial cancer formation, i.e., from normal epithelium, low- and high-grade intraepithelial neoplasia to invasive carcinoma. However, how the precancerous lesions progress to carcinoma remains elusive. Here, we report a comprehensive single-cell RNA sequencing and spatial transcriptomic study of 79 multistage esophageal lesions from 29 patients with ESCC. We reveal a gradual and significant loss of ANXA1 expression in epithelial cells due to its transcription factor KLF4 suppression along the lesion progression. We demonstrate that ANXA1 is a ligand to formyl peptide receptor type 2 (FPR2) on fibroblasts that maintain fibroblast homeostasis. Loss of ANXA1 leads to uncontrolled transformation of normal fibroblasts into cancer-associated fibroblasts (CAFs), which can be enhanced by secreted TGF-ß from malignant epithelial cells. Given the role of CAFs in cancer, our study underscores ANXA1/FPR2 signaling as an important crosstalk mechanism between epithelial cells and fibroblasts in promoting ESCC.


Assuntos
Carcinoma in Situ , Neoplasias Esofágicas , Lesões Pré-Cancerosas , Humanos , Neoplasias Esofágicas/genética , Células Epiteliais , Fibroblastos
2.
J Mater Chem B ; 10(32): 6133-6142, 2022 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-35916212

RESUMO

Silk-elastin-like protein (SELP) is an excellent biocompatible and biodegradable material for hydrogels with tunable properties that can respond to multiple external stimuli. By integrating fully atomistic, replica exchange molecular dynamics simulations with detailed experiments, we predict and measure structural responses to changes in temperature and ion concentration of a novel SELP sequence, as well as a diazonium-coupled version. A single SELP molecule shrinks at high temperatures, whereas diazonium coupling decreases this thermo-responsiveness. Diazonium coupling weakens electrostatic interactions, leading to an insignificant ionic response in the single chain, while also decreasing gelation rates by reducing the number of exposed dityrosine crosslink sites and their solvent-accessible surface areas. With further data from our coarse-grained crosslinked SELP model and our experiments, we find that three effects are critical for SELP cluster's physical response to external stimuli: (1) the structural transition of SELPs at high temperature, (2) the geometry restraints in hydrogel networks, and (3) the electrostatic interactions between molecules. This molecular understanding of the thermal and ion response in single molecules of SELPs and their crosslinked networks may further improve and help innovate SELP's stimuli-responsive properties, creating significant opportunities for applications in biomedical devices and other engineering applications.


Assuntos
Elastina , Seda , Sequência de Aminoácidos , Elastina/química , Hidrogéis/química , Seda/química
3.
Artigo em Inglês | MEDLINE | ID: mdl-26099823

RESUMO

A chemosensor consisting of two terpyridines covalently linked to a dithienosilole unit (1) has been synthesized, and its optical and metal sensing properties have been investigated. Due to the metal-organic coordination function, 1 can bind with many transition metal ions and display different fluorescence responses that cause it to function as a "turn-off" fluorescent chemosensor. A significant bathochromic shift in the fluorescence spectra is observed in the presence of Zn(2+). Meanwhile, the emission of 1 is weakened upon exposure to Ag(+) and Fe(2+) and completely quenched by Ni(2+), Co(2+), and Cu(2+). Based on the observed results, several logic gates, such as XNOR, INHIBIT, and IMPLICATION, have been achieved by controlling the chemical inputs.

4.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 18(5): 1310-5, 2010 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-21129283

RESUMO

The aim of this study was to establish an efficient method for expansion in vitro of natural killer (NK) cells highly purified from human peripheral blood. The CD3-CD56+CD16+ NK cells purified by the negative sorting method of MACS (magnetic microbeads activated cells sorting) were expanded with the different combinations of IL-2, SCF, IL-15 in SCGM (stem cell growth medium) supplemented with 10% human AB serum for 18 days. Cultures were fed with fresh medium and cytokines every 3 days. The sum of cells was counted for evaluating the efficiency of expansion. Then the purity of the CD3-CD56+CD16+ NK cells were determined by flow cytometry and the cytotoxicity to K562 targets was detected by CCK-8 assay in the end. Furthermore, the same way was used to explore the relationship between the efficiency of expansion, cytotoxicity to K562 targets of NK cells and the dose of IL-2. The results showed that after peripheral blood mononuclear cells (PBMNC) were purified by the negative sorting method of MACS, the purity of CD3-CD56+CD16+ NK cells increased from (12.70±2.66)% to (93.03±1.72)%. The CD3-CD56+CD16+ NK cells purified by MACS were expanded with the different combinations of IL-2, SCF, IL-15 in SCGM supplemented with 10% human AB serum for 18 days. The expanding multiple of IL-2/IL-15/SCF group was significantly higher than other groups (p<0.05). The purity of NK cells in the groups with cytokines was not significantly lower than that before expansion (p>0.05). The cytotoxicity of the groups with cytokines was significantly higher than that before expansion. Especially, the cytotoxicity (%) of NK cells in IL-2/IL-15 group and IL-2/IL-15/SCF group was more than 90%. The expanding multiples of low-dose group, medium-dose group and high-dose group were significantly higher than that of zero-dose group (p<0.05), but no significant difference was found between themselves (p>0.05). The cytotoxicity of the groups with IL-2 was significantly higher than that before expansion. Cytotoxicity to K562 cells in high-dose group was significantly higher than that in others (p<0.05); there was no significant difference between low-dose group and medium-dose group (p>0.05). It is concluded that cytokines in the 4 groups were efficient for expansion and the cytotoxicity of highly purified NK cells in vitro. IL-2/SCF/IL-15 combination is the most efficient one among different combinations, and enhanced significantly the cytotoxicity of NK cells against K562 targets. The efficiency of expansion and the cytotoxicity in vitro of NK cells are not related with the dose of IL-2, when IL-2<1,000 U/ml. It is indicated that IL-2 of high-dose (≥1,000 U/ml) may enhance the cytotoxicity of NK cells in vitro more efficiently.


Assuntos
Técnicas de Cultura de Células/métodos , Separação Celular/métodos , Células Matadoras Naturais/citologia , Células Matadoras Naturais/imunologia , Complexo CD3/imunologia , Antígeno CD56/imunologia , Células Cultivadas , Humanos , Imunofenotipagem , Interleucina-2/farmacologia , Células K562 , Receptores de IgG/imunologia
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