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1.
Nucleic Acids Res ; 51(21): 11568-11583, 2023 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-37850650

RESUMEN

The cistrome consists of all cis-acting regulatory elements recognized by transcription factors (TFs). However, only a portion of the cistrome is active for TF binding in a specific tissue. Resolving the active cistrome in plants remains challenging. In this study, we report the assay sequential extraction assisted-active TF identification (sea-ATI), a low-input method that profiles the DNA sequences recognized by TFs in a target tissue. We applied sea-ATI to seven plant tissues to survey their active cistrome and generated 41 motif models, including 15 new models that represent previously unidentified cis-regulatory vocabularies. ATAC-seq and RNA-seq analyses confirmed the functionality of the cis-elements from the new models, in that they are actively bound in vivo, located near the transcription start site, and influence chromatin accessibility and transcription. Furthermore, comparing dimeric WRKY CREs between sea-ATI and DAP-seq libraries revealed that thermodynamics and genetic drifts cooperatively shaped their evolution. Notably, sea-ATI can identify not only positive but also negative regulatory cis-elements, thereby providing unique insights into the functional non-coding genome of plants.


Asunto(s)
Plantas , Factores de Transcripción , Vocabulario , Cromatina , Unión Proteica/genética , Secuencias Reguladoras de Ácidos Nucleicos , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Plantas/genética
2.
Mol Carcinog ; 63(4): 563-576, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38085124

RESUMEN

Oral squamous cell carcinoma is the predominant subtype of head and neck squamous cell carcinoma, characterized by a challenging prognosis. In this study, we established a murine model of oral carcinogenesis using 4-nitroquinoline-1-oxide (4-NQO) induction to investigate the impact of immunotherapy on microenvironmental alterations. Mice in the precancerous condition were randomly divided into two groups: one receiving programmed death-1 (PD1) monoclonal antibody treatment and the other, control immunoglobulin G. Our observations showed that while PD1 blockade effectively delayed the progression of carcinogenesis, it did not completely impede or reverse it. To unravel the underlying reasons for the limited effectiveness of PD1 blockade, we collected tongue lesions and applied mass cytometry (CyTOF) and RNA sequencing (RNA-seq) to characterize the microenvironment. CyTOF analysis revealed an increased macrophage subset (expressing high levels of IFNγ and iNOS) alongside a diminished Th1-like subset (exhibiting low expression of TCF7) and three myeloid-derived suppressor cell subsets (displaying low expression of MHC Class II or IFNγ) following anti-PD1 treatment. Notably, we observed an increased presence of cancer-associated fibroblasts (CAFs) expressing collagen-related genes after PD1 blockade. Furthermore, we found a negative correlation between the infiltration levels of CAFs and CD8+ T cells. These findings were validated in murine tongue tissue slides, and publicly available multi-omics datasets. Our results suggest that CAFs may impair the therapeutic efficacy of PD1 blockade in oral carcinogenesis by the remodeling of the extracellular matrix.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias de Cabeza y Cuello , Neoplasias de la Boca , Ratones , Animales , Carcinoma de Células Escamosas/patología , Neoplasias de la Boca/inducido químicamente , Neoplasias de la Boca/genética , Linfocitos T CD8-positivos , Carcinogénesis , Carcinoma de Células Escamosas de Cabeza y Cuello , Perfilación de la Expresión Génica , Microambiente Tumoral
3.
Phys Chem Chem Phys ; 26(14): 11078-11083, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38529830

RESUMEN

The electronic and magnetic properties of d0 dilute magnetic semiconductors formed by rock-salt structured magnesium oxide (MgO) doped with C are systematically studied based on first-principles calculations and the Ising model. It is shown that the electronic holes of p states are generated due to the impurity carbon replacing oxygen in MgO, and the magnetic moment of 2µB is introduced by each C impurity. The polarization energy and formation energy of C-doped MgO are calculated, and the magnetization energy of C-doped MgO is also calculated which is used to obtain the exchange constant between C impurities. By means of the Ising model, we simulated the magnetization and the susceptibility of the doped system with increasing temperature and obtained the Curie temperature of C-doped MgO.

4.
Nature ; 559(7715): 637-641, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-30022161

RESUMEN

Diabetes is a complex metabolic syndrome that is characterized by prolonged high blood glucose levels and frequently associated with life-threatening complications1,2. Epidemiological studies have suggested that diabetes is also linked to an increased risk of cancer3-5. High glucose levels may be a prevailing factor that contributes to the link between diabetes and cancer, but little is known about the molecular basis of this link and how the high glucose state may drive genetic and/or epigenetic alterations that result in a cancer phenotype. Here we show that hyperglycaemic conditions have an adverse effect on the DNA 5-hydroxymethylome. We identify the tumour suppressor TET2 as a substrate of the AMP-activated kinase (AMPK), which phosphorylates TET2 at serine 99, thereby stabilizing the tumour suppressor. Increased glucose levels impede AMPK-mediated phosphorylation at serine 99, which results in the destabilization of TET2 followed by dysregulation of both 5-hydroxymethylcytosine (5hmC) and the tumour suppressive function of TET2 in vitro and in vivo. Treatment with the anti-diabetic drug metformin protects AMPK-mediated phosphorylation of serine 99, thereby increasing TET2 stability and 5hmC levels. These findings define a novel 'phospho-switch' that regulates TET2 stability and a regulatory pathway that links glucose and AMPK to TET2 and 5hmC, which connects diabetes to cancer. Our data also unravel an epigenetic pathway by which metformin mediates tumour suppression. Thus, this study presents a new model for how a pernicious environment can directly reprogram the epigenome towards an oncogenic state, offering a potential strategy for cancer prevention and treatment.


Asunto(s)
Adenilato Quinasa/metabolismo , Proteínas de Unión al ADN/química , Proteínas de Unión al ADN/metabolismo , Diabetes Mellitus/metabolismo , Glucosa/metabolismo , Neoplasias/metabolismo , Proteínas Proto-Oncogénicas/química , Proteínas Proto-Oncogénicas/metabolismo , 5-Metilcitosina/análogos & derivados , 5-Metilcitosina/metabolismo , Animales , ADN/química , ADN/metabolismo , Metilación de ADN , Diabetes Mellitus/genética , Dioxigenasas , Estabilidad de Enzimas , Epigénesis Genética , Hemoglobina Glucada/análisis , Humanos , Hiperglucemia/metabolismo , Metformina/farmacología , Metformina/uso terapéutico , Ratones , Ratones Desnudos , Neoplasias/tratamiento farmacológico , Neoplasias/genética , Fosforilación , Fosfoserina/metabolismo , Especificidad por Sustrato , Ensayos Antitumor por Modelo de Xenoinjerto
5.
J Hepatol ; 79(5): 1096-1109, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37463623

RESUMEN

BACKGROUND & AIMS: The molecular mechanisms underlying the progression of simple steatosis to non-alcoholic steatohepatitis (NASH) remain incompletely understood, though the potential role of epigenetic regulation by microRNA (miRNAs) is an area of increasing interest. In the present study, we aimed to investigate the role of miRNAs during steatosis-to-NASH progression, as well as underlying mechanisms. METHODS: miR-145a-5p was identified as an important checkpoint in steatosis-to-NASH progression. In vivo loss-of-function and gain-of-function studies were performed to explore the role of miR-145a-5p and Nr4a2 in NASH progression. RNA-sequencing and bioinformatic analysis were used to investigate the targets of miR-145a-5p. RESULTS: Suppression of miR-145a-5p in the liver aggravated lipid accumulation and activated hepatic inflammation, liver injury and fibrosis in steatotic mice, whereas its restoration markedly attenuated diet-induced NASH pathogenesis. Mechanistically, miR-145a-5p was able to downregulate the nuclear receptor Nr4a2 and thus inhibit the expression of NASH-associated genes. Similarly, Nr4a2 overexpression promoted steatosis-to-NASH progression while liver-specific Nr4a2 knockout mice were protected from diet-induced NASH. This role of the miR-145a-5p/Nr4a2 regulatory axis was also confirmed in primary human hepatocytes. Furthermore, the expression of miR-145a-5p was reduced and the expression of Nr4a2 was increased in the livers of patients with NASH, while their expression levels significantly negatively and positively correlated with features of liver pathology, respectively. CONCLUSIONS: Our findings highlight the role of the miR-145a-5p/Nr4a2 regulatory axis in steatosis-to-NASH progression, suggesting that either supplementation of miR-145a-5p or pharmacological inhibition of Nr4a2 in hepatocytes may provide a promising therapeutic approach for the treatment of NASH. IMPACT AND IMPLICATIONS: Non-alcoholic fatty liver disease (NAFLD) is a dynamic spectrum of chronic liver diseases ranging from simple steatosis to non-alcoholic steatohepatitis (NASH). Unfortunately, there are currently no approved drugs for NASH. Our current study identified miR-145a-5p as a novel regulator that inhibits steatosis-to-NASH progression. We found that miR-145a-5p was able to downregulate the nuclear receptor Nr4a2 to suppress the expression of NASH-associated genes. The differential expression of miR-145a-5p and Nr4a2 was further confirmed in patients with NASH, raising the possibility that supplementation of miR-145a-5p or suppression of Nr4a2 in hepatocytes might provide novel strategies for treating NASH.

6.
Plant Cell ; 32(10): 3273-3289, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32732308

RESUMEN

RNA-dependent RNA polymerase 6 (RDR6) is a core component of the small RNA biogenesis pathway, but its function in meiosis is unclear. Here, we report a new allele of OsRDR6 (Osrdr6-meiosis [Osrdr6-mei]), which causes meiosis-specific phenotypes in rice (Oryza sativa). In Osrdr6-mei, meiotic double-strand break (DSB) formation is partially blocked. We created a biallelic mutant with more severe phenotypes, Osrdr6-bi, by crossing Osrdr6-mei with a knockout mutant, Osrdr6-edit In Osrdr6-bi meiocytes, 24 univalents were observed, and no histone H2AX phosphorylation foci were detected. Compared with the wild type, the number of 21-nucleotide small RNAs in Osrdr6-mei was dramatically lower, while the number of 24-nucleotide small RNAs was significantly higher. Thousands of differentially methylated regions (DMRs) were discovered in Osrdr6-mei, implying that OsRDR6 plays an important role in DNA methylation. There were 457 genes downregulated in Osrdr6-mei, including three genes, CENTRAL REGION COMPONENT1, P31 comet , and O. sativa SOLO DANCERS, related to DSB formation. Interestingly, the downregulated genes were associated with a high level of 24-nucleotide small RNAs but less strongly associated with DMRs. Therefore, we speculate that the alteration in expression of small RNAs in Osrdr6 mutants leads to the defects in DSB formation during meiosis, which might not be directly dependent on RNA-directed DNA methylation.


Asunto(s)
Roturas del ADN de Doble Cadena , Reparación del ADN , Meiosis , Oryza/genética , Proteínas de Plantas/genética , ARN Polimerasa Dependiente del ARN/genética , Metilación de ADN , Reparación del ADN/fisiología , Regulación de la Expresión Génica de las Plantas , Mutación , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente , ARN de Planta/biosíntesis , ARN Polimerasa Dependiente del ARN/metabolismo
7.
Inorg Chem ; 62(4): 1323-1327, 2023 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-36657021

RESUMEN

Herein, we report an unprecedented asymmetric guanidinium polyiodate, namely, C(NH2)3(I3O8)(HI3O8)(H2I2O6)(HIO3)4·3H2O (1). The title compound was obtained via the hybridization of polyiodate anions and planar π-conjugated C(NH2)3+; meanwhile, its strong second-harmonic-generation (SHG) response (2.1 × KDP, where KDP = KH2PO4) and wide band gap (3.89 eV) were mainly dominated by the synergy effect of the aforementioned structural units.

8.
Inorg Chem ; 62(12): 4757-4761, 2023 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-36916671

RESUMEN

We herein report a mixed organic cationic hybrid nitrate, namely, [C(NH2)2NHNO2][C(NH2)3](NO3)2 (1). It was successfully achieved via combining three different planar groups: [(C(NH2)2NHNO2]+, C(NH2)3+, and NO3-. First-principles calculations confirm that the [(C(NH2)2NHNO2]+ group is an excellent cationic nonlinear-optical (NLO)-active unit. The title compound exhibits a moderate second-harmonic-generation (SHG) response (1.5 × KDP), a wide band gap (3.58 eV), and a suitable birefringence of 0.071 at 550 nm. Theoretical calculations indicate that the synergy effect between the [(C(NH2)2NHNO2]+ and C(NH2)3+ groups dominates the SHG process.

9.
Gastric Cancer ; 26(6): 904-917, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37572185

RESUMEN

BACKGROUND: Peroxisome proliferator-activated receptor delta (PPARδ) promotes inflammation and carcinogenesis in many organs, but the underlying mechanisms remains elusive. In stomachs, PPARδ significantly increases chemokine Ccl20 expression in gastric epithelial cells while inducing gastric adenocarcinoma (GAC). CCR6 is the sole receptor of CCL20. Here, we examine the role of PPARδ-mediated Ccl20/Ccr6 signaling in GAC carcinogenesis and investigate the underlying mechanisms. METHODS: The effects of PPARδ inhibition by its specific antagonist GSK3787 on GAC were examined in the mice with villin-promoter-driven PPARδ overexpression (PpardTG). RNAscope Duplex Assays were used to measure Ccl20 and Ccr6 levels in stomachs and spleens. Subsets of stomach-infiltrating immune cells were measured via flow cytometry or immunostaining in PpardTG mice fed GSK3787 or control diet. A panel of 13 optimized proinflammatory chemokines in mouse sera were quantified by an enzyme-linked immunosorbent assay. RESULTS: GSK3787 significantly suppressed GAC carcinogenesis in PpardTG mice. PPARδ increased Ccl20 level to chemoattract Ccr6+ immunosuppressive cells, including tumor-associated macrophages, myeloid-derived suppressor cells and T regulatory cells, but decreased CD8+ T cells in gastric tissues. GSK3787 suppressed PPARδ-induced gastric immunosuppression by inhibiting Ccl20/Ccr6 axis. Furthermore, Ccl20 protein levels increased in sera of PpardTG mice starting at the age preceding gastric tumor development and further increased with GAC progression as the mice aged. GSK3787 decreased the PPARδ-upregulated Ccl20 levels in sera of the mice. CONCLUSIONS: PPARδ dysregulation of Ccl20/Ccr6 axis promotes GAC carcinogenesis by remodeling gastric tumor microenvironment. CCL20 might be a potential biomarker for the early detection and progression of GAC.


Asunto(s)
Adenocarcinoma , PPAR delta , Neoplasias Gástricas , Humanos , Animales , Ratones , Quimiocina CCL20/genética , Quimiocina CCL20/metabolismo , PPAR delta/genética , Linfocitos T CD8-positivos , Microambiente Tumoral , Carcinogénesis , Receptores CCR6/genética , Receptores CCR6/metabolismo
10.
Phys Chem Chem Phys ; 25(28): 18932-18941, 2023 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-37408492

RESUMEN

The stopping power of energetic He ions traversing an Al film is studied by combining the time-dependent density-functional theory method with molecular dynamics simulations. We investigated the dependence of the semicore electron excitation of the Al film on the projectile's trajectory and its charge state. Our results show that for the off-channeling trajectories the semicore electrons contribute significantly to the stopping power of the Al film as the He+ ion velocity exceeds 1.0 a.u, and in contrast, it is negligible for the channeling trajectories. Most importantly, we found two unexpected effects of semicore electrons on the stopping power in helium-irradiated aluminum nanosheets, i.e., (1) the semicore electrons can contribute to the energy loss for both high and low energy projectiles under the off-channeling trajectory; (2) as the projectile velocity increases from 0.4 a.u. to 2.0 a.u. although semicore electron excitation (including transition in the target, ionization away from the target and transfer to the projectile ion) of the target atom is gradually inhibited, the influence of semicore electrons on valence electron excitation is gradually enhanced. Our finding allows us to gain new insights into the stopping of ions in metals.

11.
Phys Chem Chem Phys ; 25(13): 9043-9050, 2023 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-36883618

RESUMEN

The electronic stopping power of palladium (Pd) for protons is investigated based on time-dependent density functional theory combined with Ehrenfest molecular dynamics simulations. The electronic stopping power of Pd with explicitly considering inner electrons for protons is calculated and the excitation mechanism for the inner electrons of Pd is revealed. The velocity proportionality of the low-energy stopping power of Pd is reproduced. Our study verified that the inner electron excitation contributes significantly to the electronic stopping power of Pd in the high energy range, which is strongly dependent on the impact parameter. The electronic stopping power obtained from the off-channeling geometry is in quantitative agreement with the experimental data in a wide velocity range, and the discrepancy around the stopping maximum is further reduced by considering the relativistic correction on the binding energy of inner electrons. The velocity dependence of the mean steady-state charge of protons is quantified, and the results showed that the participation of 4p-electrons reduces the mean steady-state charge of protons, and consequently decreases the electronic stopping power of Pd in the low energy range.

12.
J Nanobiotechnology ; 21(1): 188, 2023 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-37303049

RESUMEN

BACKGROUND: Ferroptosis, a unique form of non-apoptotic cell death, is dependent on iron and lipoperoxidation, and has been shown to be associated with the pathogenesis of inflammatory bowel disease (IBD). Human umbilical cord mesenchymal stem cell-derived exosomes (hucMSC-Ex) are involved in cell survival, immune conditioning, and damage repair. However, the relationship between hucMSC-Ex, IBD, and ferroptosis is unknown. This paper explores the role of hucMSC-Ex in the repair of IBD through the regulation of the ferroptosis signaling pathway. RESULTS: In this study, we used small RNA sequencing to find that miR-129-5p was highly expressed in hucMSC-Ex, and by predicting its targeting to ACSL4, we verified the effect of miR-129-5p on mice IBD in vitro and human colonic epithelial cells (HCoEpiC) in vivo. We found that miR-129-5p reduces ferroptosis in intestinal epithelial cells by targeting ACSL4 to repair IBD, which provides new strategies for the prevention and treatment of IBD. CONCLUSION: In conclusion, our results demonstrate that hucMSC-Ex relieves IBD by targeting ACSL4 with miR-129-5p to inhibit lipid peroxidation (LPO) and ferroptosis, reducing intestinal inflammation and repairing damages. Mechanism of hucMSC-Ex inhibiting ferroptosis in intestinal epithelial cells. System Xc- mediates the transport of extracellular cystine into the cell, which gets reduced to cysteine to participate in GSH-mediated metabolism. GPX4 strongly inhibits ferroptosis by helping scavenge reactive oxygen species. The depletion of GSH correlates with decreased GPX4, and the imbalance of the antioxidant system leads to the formation of toxic phospholipid hydroperoxide, which promotes the occurrence of ferroptosis with the participation of irons. HucMSC-Ex has the ability to relieve GSH and GPX4 depletion and repair the intracellular antioxidant system. Ferric ions enter the cytosol through DMT1 and participate in lipid peroxidation. HucMSC-Ex can reduce the expression of DMT1 and alleviate this process. HucMSC-Ex-derived miR-129-5p targets ACSL4 and reduces the expression of ACSL4, an enzyme that mediates the conversion of PUFAs into phospholipids in intestinal epithelial cells, and is a positive regulator of lipid peroxidation. ABBREVIATIONS: GSH, glutathione; GPX4, glutathione peroxidase 4; GSSG, oxidized glutathione; DMT1, divalent metal transporter 1; ACSL4, acyl-CoA synthetase long-chain family member 4; PUFAs, polyunsaturated fatty acids; ALOXs, lipoxygenases; CoA, coenzyme A; PL, phospholipid; PLOOH, hydroperoxides, LOH, phospholipid alcohols; LPO, lipid peroxidation.


Asunto(s)
Exosomas , Ferroptosis , Enfermedades Inflamatorias del Intestino , Células Madre Mesenquimatosas , MicroARNs , Humanos , Animales , Ratones , Antioxidantes , Enfermedades Inflamatorias del Intestino/terapia , Glutatión , MicroARNs/genética
13.
Adv Exp Med Biol ; 1433: 15-49, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37751134

RESUMEN

Lysine-specific demethylase 1 (LSD1) was the first histone demethylase discovered and the founding member of the flavin-dependent lysine demethylase family (KDM1). The human KDM1 family includes KDM1A and KDM1B, which primarily catalyze demethylation of histone H3K4me1/2. The KDM1 family is involved in epigenetic gene regulation and plays important roles in various biological and disease pathogenesis processes, including cell differentiation, embryonic development, hormone signaling, and carcinogenesis. Malfunction of many epigenetic regulators results in complex human diseases, including cancers. Regulators such as KDM1 have become potential therapeutic targets because of the reversibility of epigenetic control of genome function. Indeed, several classes of KDM1-selective small molecule inhibitors have been developed, some of which are currently in clinical trials to treat various cancers. In this chapter, we review the discovery, biochemical, and molecular mechanisms, atomic structure, genetics, biology, and pathology of the KDM1 family of lysine demethylases. Focusing on cancer, we also provide a comprehensive summary of recently developed KDM1 inhibitors and related preclinical and clinical studies to provide a better understanding of the mechanisms of action and applications of these KDM1-specific inhibitors in therapeutic treatment.


Asunto(s)
Lisina , Neoplasias , Humanos , Histonas , Neoplasias/tratamiento farmacológico , Neoplasias/genética , Histona Demetilasas/genética , Histona Demetilasas/química , Histona Demetilasas/metabolismo
14.
Plant Physiol ; 187(1): 247-262, 2021 09 04.
Artículo en Inglés | MEDLINE | ID: mdl-34618133

RESUMEN

The reproductive transition is an important event that is crucial for plant survival and reproduction. Relative to the thorough understanding of the vegetative phase transition in angiosperms, a little is known about this process in perennial conifers. To gain insight into the molecular basis of the regulatory mechanism in conifers, we used temporal dynamic transcriptome analysis with samples from seven different ages of Pinus tabuliformis to identify a gene module substantially associated with aging. The results first demonstrated that the phase change in P. tabuliformis occurred as an unexpectedly rapid transition rather than a slow, gradual progression. The age-related gene module contains 33 transcription factors and was enriched in genes that belong to the MADS (MCMl, AGAMOUS, DEFICIENS, SRF)-box family, including six SOC1-like genes and DAL1 and DAL10. Expression analysis in P. tabuliformis and a late-cone-setting P. bungeana mutant showed a tight association between PtMADS11 and reproductive competence. We then confirmed that MADS11 and DAL1 coordinate the aging pathway through physical interaction. Overexpression of PtMADS11 and PtDAL1 partially rescued the flowering of 35S::miR156A and spl1,2,3,4,5,6 mutants in Arabidopsis (Arabidopsis thaliana), but only PtMADS11 could rescue the flowering of the ft-10 mutant, suggesting PtMADS11 and PtDAL1 play different roles in flowering regulatory networks in Arabidopsis. The PtMADS11 could not alter the flowering phenotype of soc1-1-2, indicating it may function differently from AtSOC1 in Arabidopsis. In this study, we identified the MADS11 gene in pine as a regulatory mediator of the juvenile-to-adult transition with functions differentiated from the angiosperm SOC1.


Asunto(s)
Proteínas de Dominio MADS/genética , Pinus/fisiología , Proteínas de Plantas/genética , Proteínas de Dominio MADS/metabolismo , Pinus/genética , Proteínas de Plantas/metabolismo , Reproducción/genética
15.
Mol Pharm ; 19(2): 484-493, 2022 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-35084199

RESUMEN

Human umbilical cord mesenchymal stem cell-derived exosome (hucMSC-Ex) plays an important role in tissue repair and immunomodulation, leading to the mitigation of inflammatory bowel disease. However, the preventive function of hucMSC-Ex in the onset and progression of colitis-associated colon cancer (CAC) is poorly understood. In the current study, dextran sodium sulfate/azoxymethane-induced colitis mouse model was established, and the mice disease activity index, body weight, colon length, tumor counts, survival curve, tissue H&E/immunohistochemistry, and cytokines expression were analyzed to evaluate the effects of hucMSC-Ex on CAC. In addition, miR-146a mimics were transfected into colonic epithelial cells (fetal human cells) to evaluate their role in the hucMSC-Ex-mediated regulation of SUMO1. The results showed that hucMSC-Ex inhibits the expression of SUMO1 to reduce the process of CAC progression. Further analysis indicated that miR-146a targets and inhibits SUMO1 expression and its binding to ß-catenin. In conclusion, our findings showed that hucMSC-Ex is effective in alleviating the deterioration of colitis via the miR-146a-mediated inhibition of SUMO1, which is crucial in this disease process.


Asunto(s)
Colitis , Exosomas , Células Madre Mesenquimatosas , MicroARNs , Proteína SUMO-1 , Animales , Colitis/metabolismo , Colitis/patología , Colitis/terapia , Exosomas/metabolismo , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/metabolismo , Ratones , MicroARNs/metabolismo , Proteína SUMO-1/metabolismo , Transducción de Señal , Cordón Umbilical/citología
16.
Inorg Chem ; 61(26): 10182-10189, 2022 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-35708526

RESUMEN

The combination of organic and inorganic nonlinear active units to obtain organic-inorganic hybrid materials has been proved to be a very effective method to obtain nonlinear optical (NLO) materials with excellent properties. Herein we reported two hybrid melamine-based compounds, namely, acentric (C3H7N6)6(H2PO4)4(HPO4)·4H2O (1) and centrosymmetric (C3H7N6)2SO4·2H2O (2), which were synthesized via facile solvent evaporation method. Compound 1 features a three-dimensional (3D) network structure composed of ∞[(H2PO4)4(HPO4)(H2O)4]6- layers which are further linked with ∞[(C3H7N6)6]6+ layers via hydrogen bonds. Compound 2 displays a 3D structure composed of [(C3H7N6)2(SO4)(H2O)2]∞ layers further linked with each other by hydrogen bonds. Compound 1 presents a second harmonic generation signal of about 0.1 × KDP. Furthermore, UV-vis and infrared spectra, thermal analyses, and theoretical calculation were also adopted to evaluate its NLO performance. The theoretical calculations showed that the SHG response and large birefringence of 1 were primarily caused by the (C3H7N6)+, (H2PO4)-, and (HPO4)2- groups.

17.
Inorg Chem ; 61(37): 14880-14886, 2022 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-36054831

RESUMEN

In order to meet the growing needs for the laser technology and optics industries, the goal is to find suitable fundamental building blocks with large nonlinear-optical (NLO) coefficients and birefringence for an excellent-performance NLO or birefringent system. Via preliminary investigations and calculations, it has been found that the planar π-conjugated group (C9H5O6)- possesses large polarizability anisotropy (δ) and hyperpolarizability (ßmax), comparable to well-known groups such as (B3O6)3-, (C3N3O3)3-, etc. Herein, we report a new alkali-metal 3,5-dicarboxybenzoate, KC9H5O6(H2O) (KH2BTC), which crystallized in the acentric space group Pna21. Second-harmonic-generation (SHG) measurements of KH2BTC under 1064 nm laser radiation show that the SHG response of KH2BTC is 1.2 times that of KDP with type I phase-matching behavior. Birefringence measurements show that KH2BTC owns a large birefringence of about 0.372 at 550 nm. The band gap of KH2BTC obtained by ultraviolet (UV) diffuse-reflectance spectroscopy is 3.91 eV, indicating that KH2BTC has potential applications as UV NLO or birefringent materials. Theoretical calculation further confirmed that the impressive optical properties of KH2BTC are derived from the large polarizability anisotropy of the (C9H5O6)- anions.

18.
Bioorg Chem ; 127: 106008, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35868106

RESUMEN

As the traditional conservative remedy for endometrial carcinoma (EC), progesterone has great limitations due to its poor performance, and a new strategy is urgently needed. Our previous work revealed that the antipsychotic drug chlorpromazine (CPZ) has stronger antitumor activity on EC than progesterone does, which may provide a promising conservative alternative for EC patients. Unfortunately, the severe extrapyramidal symptoms (EPSs) at concentrations (>5 mg/kg) that are required for anticarcinoma activity limited its repurposing. Therefore, a series of novel CPZ derivatives were designed and synthesized to avoid EPS and retain its antitumor activity. Among them, 11·2HCl and 18 displayed greater inhibitory activity by modulating SOS1. Notably, even at a dose of 100 mg/kg, 11·2HCl/18 had little effect on the extrapyramidal system. In conclusion, 11·2HCl and 18 greatly repressed the malignant features of endometrial carcinoma and decreased extrapyramidal side effects compared with the original drug CPZ.


Asunto(s)
Antipsicóticos , Carcinoma , Antipsicóticos/farmacología , Antipsicóticos/uso terapéutico , Carcinoma/tratamiento farmacológico , Clorpromazina/efectos adversos , Humanos , Progesterona
19.
Carcinogenesis ; 42(6): 891-902, 2021 06 21.
Artículo en Inglés | MEDLINE | ID: mdl-33993220

RESUMEN

Oral squamous cell carcinoma (OSCC) is one of the most common malignancies in the head and neck with a poor prognosis. Oral cancer development is a multistep process involving carcinogenesis. Though significant advances in cancer immunotherapy over the years, there is lack of evidence for T-cell exhaustion during oral carcinogenesis. Clinical specimens from healthy donors and patients diagnosed with oral leukoplakia (OLK) or OSCC were collected for immunohistochemical staining with PD-L1, CD86, CD8, PD-1 and CTLA-4 antibodies. Meanwhile, chemically induced mouse models of oral carcinogenesis were constructed with 4-nitroquinolone-N-oxide induction. Exhaustion status of T cells was measured by flow cytometry for spleens and by multiplex immunohistochemistry for formalin-fixed paraffin-embedded lesions in multiple stages of oral carcinogenesis. The efficacy of PD-1 blockade with or without cisplatin treatment was evaluated on the mice in precancerous and OSCC stages. We observed higher expression of PD-1 in the human OLK and OSCC tissues compared with the normal, while low expression CTLA-4 in all oral mucosa tissues. Animal experiments showed that the exhausted CD4+ T cells existed much earlier than exhausted CD8+ T cells, and an increased ratio of stem-like exhausted T cells and partially exhausted T cells were detected in the experimental groups. Besides, the expression of immune checkpoint markers (PDCD1, CTLA4 and HAVCR2) was strongly positively correlated with cytokines (IFNG and IL-2). In summary, T-cell exhaustion plays a vital role in oral carcinogenesis, and PD-1 blockade can prevent the progression of oral carcinogenesis.


Asunto(s)
Carcinogénesis/efectos de los fármacos , Carcinoma de Células Escamosas/prevención & control , Inhibidores de Puntos de Control Inmunológico/farmacología , Leucoplasia Bucal/prevención & control , Mucosa Bucal/efectos de los fármacos , Neoplasias de la Boca/prevención & control , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Animales , Carcinogénesis/inmunología , Carcinogénesis/metabolismo , Carcinogénesis/patología , Carcinoma de Células Escamosas/inmunología , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patología , Estudios de Casos y Controles , Humanos , Leucoplasia Bucal/inmunología , Leucoplasia Bucal/metabolismo , Leucoplasia Bucal/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Neoplasias de la Boca/inmunología , Neoplasias de la Boca/metabolismo , Neoplasias de la Boca/patología
20.
J Transl Med ; 19(1): 254, 2021 06 10.
Artículo en Inglés | MEDLINE | ID: mdl-34112196

RESUMEN

BACKGROUND: Recent studies reporting the intricate crosstalk between cellular and molecular mediators and the lymphatic endothelium in the development of inflammatory bowel diseases (IBD) suggest altered inflammatory cell drainage and lymphatic vasculature, implicating the lymphatic system as a player in the occurrence, development, and recurrence of intestinal diseases. This article aims to review recent data on the modulatory functions of cellular and molecular components of the IBD microenvironment on the lymphatic system, particularly lymphangiogenesis. It serves as a promising therapeutic target for IBD management and treatment. The interaction with gut microbiota is also explored. MAIN TEXT: Evidence shows that cells of the innate and adaptive immune system and certain non-immune cells participate in the complex processes of inflammatory-induced lymphangiogenesis through the secretion of a wide spectrum of molecular factors, which vary greatly among the various cells. Lymphangiogenesis enhances lymphatic fluid drainage, hence reduced infiltration of immunomodulatory cells and associated-inflammatory cytokines. Interestingly, some of the cellular mediators, including mast cells, neutrophils, basophils, monocytes, and lymphatic endothelial cells (LECs), are a source of lymphangiogenic molecules, and a target as they express specific receptors for lymphangiogenic factors. CONCLUSION: The effective target of lymphangiogenesis is expected to provide novel therapeutic interventions for intestinal inflammatory conditions, including IBD, through both immune and non-immune cells and based on cellular and molecular mechanisms of lymphangiogenesis that facilitate inflammation resolution.


Asunto(s)
Enfermedades Inflamatorias del Intestino , Vasos Linfáticos , Células Endoteliales , Humanos , Inflamación , Linfangiogénesis
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