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1.
Cell ; 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38971151

RESUMO

Homologous recombination deficiency (HRD) is prevalent in cancer, sensitizing tumor cells to poly (ADP-ribose) polymerase (PARP) inhibition. However, the impact of HRD and related therapies on the tumor microenvironment (TME) remains elusive. Our study generates single-cell gene expression and T cell receptor profiles, along with validatory multimodal datasets from >100 high-grade serous ovarian cancer (HGSOC) samples, primarily from a phase II clinical trial (NCT04507841). Neoadjuvant monotherapy with the PARP inhibitor (PARPi) niraparib achieves impressive 62.5% and 73.6% response rates per RECIST v.1.1 and GCIG CA125, respectively. We identify effector regulatory T cells (eTregs) as key responders to HRD and neoadjuvant therapies, co-occurring with other tumor-reactive T cells, particularly terminally exhausted CD8+ T cells (Tex). TME-wide interferon signaling correlates with cancer cells upregulating MHC class II and co-inhibitory ligands, potentially driving Treg and Tex fates. Depleting eTregs in HRD mouse models, with or without PARP inhibition, significantly suppresses tumor growth without observable toxicities, underscoring the potential of eTreg-focused therapeutics for HGSOC and other HRD-related tumors.

2.
Plant J ; 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38985498

RESUMO

ERFs (ethylene-responsive factors) are known to play a key role in orchestrating cold stress signal transduction. However, the regulatory mechanisms and target genes of most ERFs are far from being well deciphered. In this study, we identified a cold-induced ERF, designated as PtrERF110, from trifoliate orange (Poncirus trifoliata L. Raf., also known as Citrus trifoliata L.), an elite cold-hardy plant. PtrERF110 is a nuclear protein with transcriptional activation activity. Overexpression of PtrERF110 remarkably enhanced cold tolerance in lemon (Citrus limon) and tobacco (Nicotiana tabacum), whereas VIGS (virus-induced gene silencing)-mediated knockdown of PtrERF110 drastically impaired the cold tolerance. RNA sequence analysis revealed that PtrERF110 overexpression resulted in global transcriptional reprogramming of a range of stress-responsive genes. Three of the genes, including PtrERD6L16 (early responsive dehydration 6-like transporters), PtrSPS4 (sucrose phosphate synthase 4), and PtrUGT80B1 (UDP-glucose: sterol glycosyltransferases 80B1), were confirmed as direct targets of PtrERF110. Consistently, PtrERF110-overexpressing plants exhibited higher levels of sugars and sterols compared to their wild type counterparts, whereas the VIGS plants had an opposite trend. Exogenous supply of sucrose restored the cold tolerance of PtrERF110-silencing plants. In addition, knockdown of PtrSPS4, PtrERD6L16, and PtrUGT80B1 substantially impaired the cold tolerance of P. trifoliata. Taken together, our findings indicate that PtrERF110 positively modulates cold tolerance by directly regulating sugar and sterol synthesis through transcriptionally activating PtrERD6L16, PtrSPS4, and PtrUGT80B1. The regulatory modules (ERF110-ERD6L16/SPS4/UGT80B1) unraveled in this study advance our understanding of the molecular mechanisms underlying sugar and sterol accumulation in plants subjected to cold stress.

3.
Plant Physiol ; 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38875157

RESUMO

Citrus is one of the most important fruit crop genera in the world, but many Citrus species are vulnerable to cold stress. Ichang papeda (Citrus ichangensis), a cold-hardy citrus species, holds great potential for identifying valuable metabolites that are critical for cold tolerance in Citrus. However, the metabolic changes and underlying mechanisms that regulate Ichang papeda cold tolerance remain largely unknown. In this study, we compared the metabolomes and transcriptomes of Ichang papeda and HB pummelo (Citrus grandis 'Hirado Buntan', a cold-sensitive species) to explore the critical metabolites and genes responsible for cold tolerance. Metabolomic analyses led to the identification of common and genotype-specific metabolites, consistent with transcriptomic alterations. Compared to HB pummelo under cold stress, Ichang papeda accumulated more sugars, flavonoids, and unsaturated fatty acids, which are well-characterized metabolites involved in stress responses. Interestingly, sphingosine and chlorogenic acid substantially accumulated only in Ichang papeda. Knockdown of CiSPT (C. ichangensis serine palmitoyltransferase) and CiHCT2 (C. ichangensis hydroxycinnamoyl-CoA: shikimate hydroxycinnamoyltransferase2), two genes involved in sphingosine and chlorogenic acid biosynthesis, dramatically decreased endogenous sphingosine and chlorogenic acid levels, respectively. This reduction in sphingosine and chlorogenic acid notably compromised the cold tolerance of Ichang papeda, whereas exogenous application of these metabolites increased plant cold tolerance. Taken together, our findings indicate that greater accumulation of a spectrum of metabolites, particularly sphingosine and chlorogenic acid, promotes cold tolerance in cold-tolerant citrus species. These findings broaden our understanding of plant metabolic alterations in response to cold stress and provide valuable targets that can be manipulated to improve Citrus cold tolerance.

4.
Artigo em Inglês | MEDLINE | ID: mdl-38958784

RESUMO

BACKGROUND: Cancer stem cells (CSCs) in triple-negative breast cancer (TNBC) are recognized as a highly challenging subset of cells, renowned for their heightened propensity for relapse and unfavorable prognosis. Monensin, an ionophoric antibiotic, has been reported to exhibit significant therapeutic efficacy against various cancers, especially CSCs. Erlotinib is classified as one of the EGFR-TKIs and has been previously identified as a promising therapeutic target for TNBC. Our research aims to assess the effectiveness of combination of monensin and erlotinib as a potential treatment strategy for TNBC. METHODS: The combination of monensin and erlotinib was assessed for its potential anticancer activity through various in vitro assays, including cytotoxicity assay, colony formation assay, wound healing assay, transwell assay, mammosphere formation assay, and proportion of CSCs assay. Additionally, an in vivo study using tumor-bearing nude mice was conducted to evaluate the inhibitory effect of the monensin and erlotinib combination on tumor growth. RESULTS: The results indicated that combination of monensin with erlotinib synergistically inhibited cell proliferation, the migration rate, the invasion ability and decreased the CSCs proportion, and CSC markers SOX2 and CD133 in vivo and in vitro. Furthermore, the primary proteins involved in the signaling pathways of the EGFR/ERK and PI3K/AKT are simultaneously inhibited by the combination treatment of monensin and erlotinib in vivo and in vitro. CONCLUSIONS: The simultaneous inhibition of the EGFR/ERK and PI3K/AKT/mTOR signaling pathways by the combination of monensin and erlotinib exhibited a synergistic effect on suppressing tumor proliferation and cancer cell stemness in TNBC.

5.
Plant Physiol ; 191(1): 591-609, 2023 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-36102815

RESUMO

ß-Amylase (BAM)-mediated starch degradation is a main source of soluble sugars that help plants adapt to environmental stresses. Here, we demonstrate that dehydration-induced expression of PtrBAM3 in trifoliate orange (Poncirus trifoliata (L.) Raf.) functions positively in drought tolerance via modulation of starch catabolism. Two transcription factors, PtrABF4 (P. trifoliata abscisic acid-responsive element-binding factor 4) and PtrABR1 (P. trifoliata ABA repressor 1), were identified as upstream transcriptional activators of PtrBAM3 through yeast one-hybrid library screening and protein-DNA interaction assays. Both PtrABF4 and PtrABR1 played a positive role in plant drought tolerance by modulating soluble sugar accumulation derived from BAM3-mediated starch decomposition. In addition, PtrABF4 could directly regulate PtrABR1 expression by binding to its promoter, leading to a regulatory cascade to reinforce the activation of PtrBAM3. Moreover, PtrABF4 physically interacted with PtrABR1 to form a protein complex that further promoted the transcriptional regulation of PtrBAM3. Taken together, our finding reveals that a transcriptional cascade composed of ABF4 and ABR1 works synergistically to upregulate BAM3 expression and starch catabolism in response to drought condition. The results shed light on the understanding of the regulatory molecular mechanisms underlying BAM-mediated soluble sugar accumulation for rendering drought tolerance in plants.


Assuntos
Fatores de Transcrição , beta-Amilase , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Resistência à Seca , Amilases/genética , Proteínas de Plantas/metabolismo , Ácido Abscísico/metabolismo , Carboidratos , Secas , Açúcares , beta-Amilase/genética , Amido/metabolismo , Regulação da Expressão Gênica de Plantas , Plantas Geneticamente Modificadas/metabolismo , Estresse Fisiológico
6.
Artigo em Inglês | MEDLINE | ID: mdl-38924426

RESUMO

OBJECTIVE: The aim of this study was to develop and validate an interpretable and highly generalizable multimodal radiomics model for predicting the prognosis of patients with cerebral hemorrhage. METHODS: This retrospective study involved 237 patients with cerebral hemorrhage from 3 medical centers, of which a training cohort of 186 patients (medical center 1) was selected and 51 patients from medical center 2 and medical center 3 were used as an external testing cohort. A total of 1762 radiomics features were extracted from nonenhanced computed tomography using Pyradiomics, and the relevant macroscopic imaging features and clinical factors were evaluated by 2 experienced radiologists. A radiomics model was established based on radiomics features using the random forest algorithm, and a radiomics-clinical model was further trained by combining radiomics features, clinical factors, and macroscopic imaging features. The performance of the models was evaluated using area under the curve (AUC), sensitivity, specificity, and calibration curves. Additionally, a novel SHAP (SHAPley Additive exPlanations) method was used to provide quantitative interpretability analysis for the optimal model. RESULTS: The radiomics-clinical model demonstrated superior predictive performance overall, with an AUC of 0.88 (95% confidence interval, 0.76-0.95; P < 0.01). Compared with the radiomics model (AUC, 0.85; 95% confidence interval, 0.72-0.94; P < 0.01), there was a 0.03 improvement in AUC. Furthermore, SHAP analysis revealed that the fusion features, rad score and clinical rad score, made significant contributions to the model's decision-making process. CONCLUSION: Both proposed prognostic models for cerebral hemorrhage demonstrated high predictive levels, and the addition of macroscopic imaging features effectively improved the prognostic ability of the radiomics-clinical model. The radiomics-clinical model provides a higher level of predictive performance and model decision-making basis for the risk prognosis of cerebral hemorrhage.

7.
BMC Cancer ; 23(1): 887, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37730543

RESUMO

BACKGROUND: The relationship between migraine and breast cancer risk has generated conflicting findings. We attempted to assess the association between migraine and breast cancer risk using Mendelian randomization (MR) analysis. METHODS: We selected genetic instruments associated with migraine from a recently published genome-wide association studies (GWAS). Inverse variant weighted (IVW) analysis was adopted as the main method, and we also performed the weighted-median method and the MR‒Egger, MR pleiotropy residual sum and outlier (MR-PRESSO), and MR Robust Adjusted Profile Score (MR-RAPS) methods as supplements. RESULTS: Our MR suggested that any migraine (AM) was a risk factor for overall breast cancer (IVW: odds ratio (OR) = 1.072, 95% confidence intervals (CI) = 1.035-1.110, P = 8.78 × 10- 5, false discovery rate (FDR) = 7.36 × 10- 4) and estrogen receptor-positive (ER+) breast cancer (IVW: OR = 1.066, 95% CI = 1.023-1.111, P = 0.0024; FDR = 0.0108) but not estrogen receptor-negative (ER-) breast cancer. In its subtype analysis, women with a history of migraine without aura (MO) had an increased risk of ER- breast cancer (IVW: OR = 1.089, 95% CI = 1.019-1.163, P = 0.0118, FDR = 0.0354), and MO was suggestively associated with the risk of overall breast cancer (FDR > 0.05 and IVW P < 0.05). No significant heterogeneity or horizontal pleiotropy was found in the sensitivity analysis. CONCLUSION: This study suggested that women with AM have an increased risk of overall breast cancer and ER + breast cancer. MO was suggestively associated with the risk of overall breast cancer and ER- breast cancer.


Assuntos
Neoplasias da Mama , Transtornos de Enxaqueca , Feminino , Humanos , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/genética , Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Mama , Transtornos de Enxaqueca/complicações , Transtornos de Enxaqueca/genética
8.
Mol Cell ; 60(6): 914-29, 2015 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-26687600

RESUMO

Multicellular organisms have multiple homologs of the yeast ATG8 gene, but the differential roles of these homologs in autophagy during development remain largely unknown. Here we investigated structure/function relationships in the two C. elegans Atg8 homologs, LGG-1 and LGG-2. lgg-1 is essential for degradation of protein aggregates, while lgg-2 has cargo-specific and developmental-stage-specific roles in aggregate degradation. Crystallography revealed that the N-terminal tails of LGG-1 and LGG-2 adopt the closed and open form, respectively. LGG-1 and LGG-2 interact differentially with autophagy substrates and Atg proteins, many of which carry a LIR motif. LGG-1 and LGG-2 have structurally distinct substrate binding pockets that prefer different residues in the interacting LIR motif, thus influencing binding specificity. Lipidated LGG-1 and LGG-2 possess distinct membrane tethering and fusion activities, which may result from the N-terminal differences. Our study reveals the differential function of two ATG8 homologs in autophagy during C. elegans development.


Assuntos
Autofagia , Proteínas de Caenorhabditis elegans/química , Caenorhabditis elegans/metabolismo , Proteínas Associadas aos Microtúbulos/química , Animais , Família da Proteína 8 Relacionada à Autofagia , Sítios de Ligação , Caenorhabditis elegans/química , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Cristalografia por Raios X , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Modelos Moleculares , Mutação , Conformação Proteica , Proteínas Serina-Treonina Quinases/metabolismo , Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/genética
9.
Molecules ; 28(13)2023 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-37446845

RESUMO

At present, it is still a challenge to prepare multifunctional composite nanomaterials with simple composition and favorable structure. Here, multifunctional Fe3O4@nitrogen-doped carbon (N-C) nanocomposites with hollow porous core-shell structure and significant electrochemical, adsorption and sensing performances were successfully synthesized through the hydrothermal method, polymer coating, then thermal annealing process in nitrogen (N2) and lastly etching in hydrochloric acid (HCl). The morphologies and properties of the as-obtained Fe3O4@N-C nanocomposites were markedly affected by the etching time of HCl. When the Fe3O4@N-C nanocomposites after etching for 30 min (Fe3O4@N-C-3) were applied as the anodes for lithium-ion batteries (LIBs), the invertible capacity could reach 1772 mA h g-1 after 100 cycles at the current density of 0.2 A g-1, which is much better than that of Fe3O4@N-C nanocomposites etched, respectively, for 15 min and 45 min (948 mA h g-1 and 1127 mA h g-1). Additionally, the hollow porous Fe3O4@N-C-3 nanocomposites also exhibited superior rate capacity (950 mA h g-1 at 0.6 A g-1). The excellent electrochemical properties of Fe3O4@N-C nanocomposites are attributed to their distinctive hollow porous core-shell structure and appropriate N-doped carbon coating, which could provide high-efficiency transmission channels for ions/electrons, improve the structural stability and accommodate the volume variation in the repeated Li insertion/extraction procedure. In addition, the Fe3O4@N-C nanocomposites etched by HCl for different lengths of time, especially Fe3O4@N-C-3 nanocomposites, also show good performance as adsorbents for the removal of the organic dye (methyl orange, MO) and surface-enhanced Raman scattering (SERS) substrates for the determination of a pesticide (thiram). This work provides reference for the design and preparation of multifunctional materials with peculiar pore structure and uncomplicated composition.


Assuntos
Lítio , Nanocompostos , Porosidade , Análise Espectral Raman , Eletrodos , Carbono , Ácido Clorídrico , Íons , Nitrogênio
10.
J Sci Food Agric ; 103(5): 2473-2482, 2023 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-36658470

RESUMO

BACKGROUND: Myosin is the most important component of myofibrillar protein, with excellent gelling properties. To date, heating treatment remains the mainstream method for forming gel in meat products, and it has the most extensive application in the field of meat industry. However, at present, there are few reports on the effects of heating rates on myosin self-assembly and aggregation behavior during heating treatment. RESULTS: The present study aimed to investigate the effects of different heating rates (1, 2, 3 and 5 °C min-1 ) on the self-assembly behavior, physicochemical, structural and gelling properties of myosin. At the lowest heating rate of 1 °C min-1 , the myosin gel had a dense microstructure, the highest elastic modulus (G') and water holding capacity compared to higher heating rates (2, 3 and 5 °C min-1 ). At higher temperatures (40, 45 °C), the surface hydrophobicity, turbidity, particle size distribution and self-assembly behavior of myosin in pre-gelling solutions showed that myosin had sufficient time to denature, underwent full structure unfolding before aggregation at the heating rate of 1°C min-1 , and formed regular and homogeneous spherical aggregates. Therefore, the myosin gel also had a better three-dimensional network. CONCLUSION: The heating rates had an important effect on the quality of myosin gels, and had theoretical implications for improving the quality of meat gel products. © 2023 Society of Chemical Industry.


Assuntos
Calefação , Miosinas , Animais , Bovinos , Miosinas/química , Temperatura Alta , Interações Hidrofóbicas e Hidrofílicas , Géis/química
11.
Zhonghua Nan Ke Xue ; 29(3): 195-201, 2023 Mar.
Artigo em Zh | MEDLINE | ID: mdl-38597699

RESUMO

OBJECTIVE: To investigate the effects of different concentrations of Rauwolfia extract (RE) on the proliferation of prostate cells in the rat model of benign prostatic hyperplasia (BPH). METHODS: We randomly divided 48 male SD rats into six groups of an equal number, BPH model control, finasteride, low-concentration RE, medium-concentration RE, high-concentration RE and normal control, and established a BPH model in the former five groups by subcutaneous injection of testosterone propionate following castration. We treated the rats of the finasteride and RE groups intragastrically with finasteride solution at 5 mg/kg and RE at 5, 10 and 20 mg/kg respectively, and those of the model control and normal control groups with an equal dose of normal saline, all once a day for 28 consecutive days. Then, we killed all the animals, collected their prostate tissue, obtained the wet weight and volume of the prostate, the prostate index and the contents of serum T and dihydrotestosterone (DHT), observed the morphological changes of the prostate tissue by HE staining, counted the glands in the prostate tissue, measured the intraglandular area, and determined the expressions of PCNA and α-SMA by immunohistochemistry. RESULTS: Compared with the rats of the normal control group, the BPH model controls showed significantly increased wet weight (ï¼»0.923 ± 0.15ï¼½ vs ï¼»1.455 ± 0.52ï¼½ g, P < 0.05), volume (ï¼»1.035 ± 0.29ï¼½ vs ï¼»1.687 ± 0.31ï¼½ ml, P < 0.05) and index of the prostate (ï¼»0.23 ± 0.04ï¼½% vs ï¼»0.37 ± 0.15ï¼½%, P < 0.05), dilation, hyperemia and edema of the prostatic stroma and vessels, and proliferation rate of the prostatic cells, but remarkably decreased number of glands (ï¼»20.35 ± 3.83ï¼½ vs ï¼»12.56 ± 2.58ï¼½, P < 0.05), epithelial thickness (ï¼»39.76 ± 5.20ï¼½ vs ï¼»19.52 ± 1.52ï¼½ µm, P < 0.05) and intraglandular area (ï¼»12.3 ± 1.21ï¼½ vs ï¼»5.96 ± 0.34ï¼½ ×103µm2, P < 0.05). In comparison with the BPH model controls, the animals treated with RE, especially in the high-concentration RE group, exhibited marked decreases in the weight (ï¼»1.455 ± 0.52ï¼½ vs ï¼»0.862 ± 0.31ï¼½ g, P < 0.05), volume ( ï¼»1.687 ± 0.31ï¼½ vs ï¼»0.952 ± 0.28ï¼½ ml, P < 0.05) and index of the prostate (ï¼»0.37 ± 0.15ï¼½% vs ï¼»0.22 ± 0.07ï¼½%, P < 0.05), dramatic improvement in the number of glands (ï¼»12.56 ± 2.58ï¼½ vs ï¼»18.36 ± 1.25ï¼½, P < 0.05), epithelial thickness (ï¼»39.76 ± 5.20ï¼½ vs ï¼»19.04 ± 3.89ï¼½ µm, P < 0.05) and intraglandular area (ï¼»5.96 ± 0.34ï¼½ vs ï¼»10.25 ± 0.98ï¼½ ×103µm2, P<0.05ï¼½, P < 0.05), remarkable down-regulation of the expressions of PCNA and α-SMA, and significant reduction of the contents of serum T (ï¼»19.147 ± 3.214ï¼½ vs ï¼»6.016 ± 1.978ï¼½ ng/ml, P < 0.05) and DHT (ï¼»9.052 ± 0.633ï¼½ vs ï¼»2.532 ± 0.386ï¼½ ng/ml, P < 0.05). CONCLUSION: Rauwolfia extract can inhibit the proliferation of prostate cells and relieve BPH symptoms in a concentration-dependent manner in rats with BPH.


Assuntos
Alcaloides , Hiperplasia Prostática , Rauwolfia , Humanos , Ratos , Masculino , Animais , Próstata/metabolismo , Hiperplasia Prostática/metabolismo , Finasterida/farmacologia , Rauwolfia/metabolismo , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Antígeno Nuclear de Célula em Proliferação/metabolismo , Ratos Sprague-Dawley , Alcaloides/uso terapêutico , Di-Hidrotestosterona , Proliferação de Células , Testosterona
12.
Chembiochem ; 23(21): e202200387, 2022 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-36073901

RESUMO

Gene therapy offers an alternative and promising avenue to lung cancer treatment. Here, we used dibenzocyclooctyne (DBCO)-branched primers to construct a PTEN gene nanovector (NP-PTEN) through branch-PCR. NP-PTEN showed the nanoscale structure with biocompatible size (84.7±11.2 nm) and retained the improved serum stability compared to linear DNA. When transfected into NCI-H1299 cancer cells, NP-PTEN could overexpress PTEN protein to restore PTEN functions through the deactivation of PI3K-AKT-mTOR signaling pathway to inhibit cell proliferation and induce cell apoptosis. The apoptosis rate of NCI-H1299 cancer cells could reach up to 54.5 %±4.6 % when the transfection concentration of NP-PTEN was 4.0 µg/mL. In mice bearing NCI-H1299 tumor xenograft intratumorally administrated with NP-PTEN, the average tumor volume and tumor weight was separately reduced by 61.7 % and 63.9 %, respectively, compared with the PBS group on the 18th  day of administration. The anticancer efficacy of NP-PTEN in NCI-H1299 tumor xenograft suggests the promising therapeutic potential of branch-PCR assembled PTEN gene nanovectors in lung cancer gene therapy and also provided more opportunities to introduce two or more tumor suppressor genes as an all-in-one gene nanovector for multiple gene-based cancer gene therapy.


Assuntos
Neoplasias Pulmonares , Fosfatidilinositol 3-Quinases , Humanos , Camundongos , Animais , Fosfatidilinositol 3-Quinases/genética , Linhagem Celular Tumoral , Neoplasias Pulmonares/terapia , Neoplasias Pulmonares/tratamento farmacológico , Proliferação de Células , Apoptose , Pulmão/metabolismo , Reação em Cadeia da Polimerase , Genes Neoplásicos , Proteínas Proto-Oncogênicas c-akt/metabolismo , PTEN Fosfo-Hidrolase/genética
13.
New Phytol ; 235(6): 2331-2349, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35695205

RESUMO

Invertase (INV)-mediated sucrose (Suc) hydrolysis, leading to the irreversible production of glucose (Glc) and fructose (Frc), plays an essential role in abiotic stress tolerance of plants. However, the regulatory network associated with the Suc catabolism in response to cold environment remains largely elusive. Herein, the cold-induced alkaline/neutral INV gene PtrA/NINV7 of trifoliate orange (Poncirus trifoliata (L.) Raf.) was shown to function in cold tolerance via mediating the Suc hydrolysis. Meanwhile, a nuclear matrix-associated region containing A/T-rich sequences within its promoter was indispensable for the cold induction of PtrA/NINV7. Two AT-Hook Motif Containing Nuclear Localized (AHL) proteins, PtrAHL14 and PtrAHL17, were identified as upstream transcriptional activators of PtrA/NINV7 by interacting with the A/T-rich motifs. PtrAHL14 and PtrAHL17 function positively in the cold tolerance by modulating PtrA/NINV7-mediated Suc catabolism. Furthermore, both PtrAHL14 and PtrAHL17 could form homo- and heterodimers between each other, and interacted with two histone acetyltransferases (HATs), GCN5 and TAF1, leading to elevated histone3 acetylation level under the cold stress. Taken together, our findings unraveled a new cold-responsive signaling module (AHL14/17-HATs-A/NINV7) for orchestration of Suc catabolism and cold tolerance, which shed light on the molecular mechanisms underlying Suc catabolism catalyzed by A/NINVs under cold stress.


Assuntos
Citrus , Poncirus , Citrus/genética , Temperatura Baixa , Resposta ao Choque Frio/fisiologia , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Poncirus/genética , Poncirus/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Sacarose/metabolismo , beta-Frutofuranosidase/metabolismo
14.
Org Biomol Chem ; 20(20): 4128-4134, 2022 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-35510487

RESUMO

The thiolysis of NBD piperazinyl amine (NBD-PZ) is highly selective for H2S over GSH and has been widely used for the development of many H2S fluorescent probes. Whether the NBD amine in H2S-specific probes could be a fluorescent quencher should be further clarified, because NBD amines have been used as environment-sensitive fluorophores for many years. Here, we compared the properties of NBD-based secondary and tertiary amines under the same conditions. For example, the emission of NBD-N(Et)2 is much smaller in water and less responsive to changes in polarity than that of NBD-NHEt. The emission of NBD-PZ-TPP is also smaller than that of NBD-NH-TPP both in aqueous buffer and in live cells. In addition, confocal bioimaging signals of NBD-PZ-TPP with excitation at 405 nm and 454 nm are much weaker than that at 488 nm. Based on these results as well as the previous work on NBD-based probes, we discuss and summarize the design strategies and sensing mechanisms for different NBD-based H2S probes. Moreover, NBD-PZ-TPP may be a useful tool for reaction with and imaging of mitochondrial H2S in live cells. This work should be useful for clarification of the roles of NBD in H2S-specific fluorescent probes as well as for facilitating the development of future NBD-based probes.


Assuntos
Corantes Fluorescentes , Sulfeto de Hidrogênio , Aminas , Ionóforos , Mitocôndrias
15.
World J Surg Oncol ; 20(1): 361, 2022 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-36372891

RESUMO

BACKGROUND: Many studies have reported the relationship between prognosis and Slug protein expression in breast cancer patients, but the results are discrepant. Therefore, there is a need for meta-analyses with high statistical power to investigate and further explore their relationship. METHODS: We used PubMed, Embase, the Cochrane Library, Scopus, MEDLINE, and the Web of Science to find studies on breast cancer and Slug. Overall survival (OS) and disease-free survival (DFS) were the study's primary endpoints. We pooled hazard ratios (HRs) and odds ratios (ORs) to assess the association between Slug protein expression and prognostic and clinicopathological parameters. This study was performed using STATA version 14.0 for data analysis. (Stata Corporation, TX, USA). RESULTS: We conducted a literature search by searching six online databases. Ultimately, we obtained eight studies including 1458 patients through strict exclusion criteria. The results showed that increased Slug protein expression resulted in poorer OS (HR = 2.21; 95% CI = 1.47-3.33; P < 0.001) and DFS (HR = 2.03; 95% CI = 1.26-3.28; P = 0.004) in breast cancer patients. In addition, the results suggested that breast cancer patients with increased Slug protein expression had a higher TNM stage (I-II vs III-IV; OR = 0.42; 95% CI = 0.25-0.70; P = 0.001), a greater tendency to have axillary lymph node metastases (N+ vs N0; OR = 2.16; 95% CI = 1.31-3.56; P = 0.003) and were more prone to estrogen receptor deficiency (positive vs negative; OR = 0.67; 95% CI = 0.45-0.99; P = 0.042). However, Slug protein expression was not associated with age, histological grade, tumor size, progesterone receptor status, or human epidermal growth factor receptor 2 status in breast cancer patients. CONCLUSION: This meta-analysis showed that elevated Slug protein expression may be related to poor outcomes in patients with breast cancer. Therefore, Slug is not only an indicator of patient survival but may also become a new target for breast cancer therapy.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Prognóstico , Neoplasias da Mama/patologia , Intervalo Livre de Doença , Metástase Linfática , Receptores de Estrogênio
16.
J Cell Mol Med ; 25(18): 8836-8849, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34378321

RESUMO

Colorectal cancer (CRC) is the third most malignant tumour worldwide, with high mortality and recurrence. Chemoresistance is one of the main factors leading to metastasis and poor prognosis in advanced CRC patients. By analysing the Gene Expression Omnibus data set, we found higher hexokinase 2 (HK2) expression levels in patients with metastatic CRC than in those with primary CRC. Moreover, we observed higher enrichment in oxaliplatin resistance-related gene sets in metastatic CRC than in primary CRC. However, the underlying relationship has not yet been elucidated. In our study, HK2 expression was significantly elevated in CRC patients. Gene set enrichment analysis (GSEA) revealed multi-drug resistance and epithelial-mesenchymal transition (EMT) pathways related to high HK2 expression. Our results showed that knockdown of HK2 significantly inhibited vimentin and Twist1 expression and promoted TJP1 and E-cadherin expression in CRC cells. Additionally, transcriptional and enzymatic inhibition of HK2 by 3-bromopyruvate (3-bp) impaired oxaliplatin resistance in vitro and in vivo. Mechanistically, HK2 interacts with and stabilized Twist1 by preventing its ubiquitin-mediated degradation, which is related to oxaliplatin resistance, in CRC cells. Overexpression of Twist1 reduced the apoptosis rate by HK2 knockdown in CRC cells. Collectively, we discovered that HK2 is a crucial regulator that mediates oxaliplatin resistance through Twist1. These findings identify HK2 and Twist1 as promising drug targets for CRC chemoresistance.


Assuntos
Neoplasias Colorretais/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos , Regulação Neoplásica da Expressão Gênica , Hexoquinase/metabolismo , Proteínas Nucleares/metabolismo , Oxaliplatina/farmacologia , Proteína 1 Relacionada a Twist/metabolismo , Animais , Linhagem Celular Tumoral , Humanos , Camundongos , Camundongos Endogâmicos BALB C
17.
BMC Gastroenterol ; 21(1): 297, 2021 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-34301194

RESUMO

BACKGROUND: Approximately 5.0-24.2% of colorectal cancers (CRCs) have inactivating mutations in SMAD4, making it one of the frequently mutated genes in CRC. We thus carried out a comprehensive system review and meta-analysis investigating the prognostic significance and clinicopathological features of SMAD4 gene mutation in CRC patients. METHODS: A detailed literature search was conducted in PubMed, Web of Science and Embase databases to study the relationship between SMAD4 mutations and the demographic and clinicopathological characteristics in CRC patients. The hazard ratios (HRs) with 95% confidence intervals (CI) were used to evaluate the effect of SMAD4 mutations on overall survival (OS) and progression-free survival (PFS)/recurrence-free survival (RFS). RESULTS: Ten studies enrolling 4394 patients were eligible for inclusion. Data on OS were available from 5 studies and data on PFS/RFS were available from 3 studies. Comparing SMAD4-mutated CRC patients with SMAD4 wild-type CRC patients, the summary HR for OS was 1.46 (95% CI 1.28-1.67, P = 0.001), the summary HR for PFS/RFS was 1.59 (95% CI 1.14-2.22, P = 0.006). In terms of clinicopathology parameters, 9 studies have data that can be extracted, SMAD4 mutations were associated with tumor location (odds ratio [OR] = 1.15, colon/rectum, 95% CI 1.01-1.31, P = 0.042), TNM stage (OR = 1.28, stage IV/I-III, 95% CI 1.03-1.58, P = 0.025), lymph node metastasis (OR = 1.42, N1 + N2/N0, 95% CI 1.20-1.67, P < 0.001), mucinous differentiation (OR = 2.23, 95% CI 1.85-2.70, P < 0.001) and rat sarcoma viral oncogene homolog (RAS) mutation status (OR = 2.13, 95% CI 1.37-3.34, P = 0.001). No connection was found with age, gender, tumor grade, microsatellite instability status and b-viral oncogene homolog B1 mutation status. Besides, publication bias was not observed in any study. CONCLUSIONS: This meta-analysis suggests that SMAD4 mutation was associated with OS, PFS/RFS, and clinicopathological parameters, including tumor site, disease stage, RAS status, lymph node metastasis and mucinous differentiation. Our meta-analysis indicated that SMAD4 mutations could predict the poor prognosis and aggressive clinicopathological characteristics of CRC. More large-sample cohort studies are needed to confirm this conclusion. Since SMAD4 mutations are closely related to RAS mutations, their relationship warrants further investigation.


Assuntos
Neoplasias Colorretais , Proteína Smad4 , Biomarcadores Tumorais/genética , Neoplasias Colorretais/genética , Humanos , Instabilidade de Microssatélites , Mutação , Prognóstico , Proteína Smad4/genética
18.
Environ Res ; 200: 111424, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34126049

RESUMO

As the emerging contaminants, the behavior and fate of microplastics (MPs) were highly related to the interactions with surrounding organic matters. However, information on the effects of molecular sizes of organic matters on the interaction is still lacking. In this study, the bulk algal-derived organic matter (AOM) samples were obtained and further fractionated into high molecular weight (HMW-, 1kDa-0.45 µm) and low molecular weight (LMW-, < 1 kDa) fractions. The interaction between MPs [polyethylene (PE) and polystyrene (PS)] and these MW-fractionated AOMs were characterized by dissolved organic carbon, fluorescence and absorbance spectroscopy, and fourier transform infrared (FTIR) analysis. Results showed that presence of AOM could effectively inhibit the release of additives from MPs. Further analysis found that the inhibition extents decreased in the order of HMW- > bulk > LMW-AOM. The absorbance and fluorescence spectroscopy showed that aromatic protein-like substances in HMW fraction exhibited higher adsorption affinity to MPs than the bulk and LMW counterparts. The strong sorption of aromatic substances may offer more binding sites for additives to inhibit the release of organic substances. Moreover, two dimensional FTIR correlation spectroscopy revealed that the HMW non-aromatic substances were preferentially adsorbed onto PS, which led to an enhanced adsorption capacity to additives by forming H-bonding. Therefore, the MW- and component-dependent heterogeneities of AOM samples must be fully considered in evaluating the environmental behavior of MPs.


Assuntos
Microplásticos , Poluentes Químicos da Água , Adsorção , Peso Molecular , Plásticos , Poliestirenos , Poluentes Químicos da Água/análise
19.
Mar Drugs ; 19(5)2021 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-34066101

RESUMO

Gracilariopsis lemaneiformis polysaccharides (GLP) were degraded using pectinase, glucoamylase, cellulase, xylanase, and ß-dextranase into low-molecular-weight polysaccharides, namely, GPP, GGP, GCP, GXP, and GDP, respectively, and their antioxidant capacities were investigated. The degraded GLP showed higher antioxidant activities than natural GLP, and GDP exhibited the highest antioxidant activity. After the optimization of degradation conditions through single-factor and orthogonal optimization experiments, four polysaccharide fractions (GDP1, GDP2, GDP3, and GDP4) with high antioxidant abilities (hydroxyl radical scavenging activity, DPPH radical scavenging activity, reduction capacity, and total antioxidant capacity) were obtained. Their cytoprotective activities against H2O2-induced oxidative damage in human fetal lung fibroblast 1 (HFL1) cells were examined. Results suggested that GDP pretreatment can significantly improve cell viability, reduce reactive oxygen species and malonaldehyde levels, improve antioxidant enzyme activity and mitochondria membrane potential, and alleviate oxidative damage in HFL1 cells. Thus, the enzyme degradation of GLP with ß-dextranase can significantly improve its antioxidant activity, and GDP might be a suitable source of natural antioxidants.


Assuntos
Antioxidantes/metabolismo , Antioxidantes/farmacologia , Polissacarídeos/metabolismo , Polissacarídeos/farmacologia , Rodófitas/química , Antioxidantes/análise , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Glicosídeo Hidrolases/metabolismo , Humanos , Peróxido de Hidrogênio/toxicidade , Hidrólise , Radical Hidroxila/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Peso Molecular , Estresse Oxidativo/efeitos dos fármacos , Polissacarídeos/análise , Espécies Reativas de Oxigênio/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier
20.
J Cell Mol Med ; 24(13): 7405-7416, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32463161

RESUMO

As an outcome of chronic liver disease, liver fibrosis involves the activation of hepatic stellate cells (HSCs) caused by a variety of chronic liver injuries. It is important to explore approaches to inhibit the activation and proliferation of HSCs for the treatment of liver fibrosis. PLK1 is overexpressed in many human tumour cells and has become a popular drug target in tumour therapy. Therefore, further study of the function of PLK1 in the cell cycle is valid. In the present study, we found that PLK1 expression was elevated in primary HSCs isolated from CCl4 -induced liver fibrosis mice and LX-2 cells stimulated with TGF-ß1. Knockdown of PLK1 inhibited α-SMA and Col1α1 expression and reduced the activation of HSCs in CCl4 -induced liver fibrosis mice and LX-2 cells stimulated with TGF-ß1. We further showed that inhibiting the expression of PLK1 reduced the proliferation of HSCs and promoted HSCs apoptosis in vivo and in vitro. Furthermore, we found that the Wnt/ß-catenin signalling pathway may be essential for PLK1-mediated HSCs activation. Together, blocking PLK1 effectively suppressed liver fibrosis by inhibiting HSC activation, which may provide a new treatment strategy for liver fibrosis.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Células Estreladas do Fígado/enzimologia , Células Estreladas do Fígado/patologia , Cirrose Hepática/enzimologia , Cirrose Hepática/patologia , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Via de Sinalização Wnt , Animais , Apoptose , Tetracloreto de Carbono , Linhagem Celular , Proliferação de Células , Humanos , Masculino , Camundongos Endogâmicos C57BL , Modelos Biológicos , Fator de Crescimento Transformador beta1/metabolismo , Regulação para Cima , Quinase 1 Polo-Like
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