794 results
Search Results
2. Neutrophils extracellular traps and ferroptosis in diabetic wounds.
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Huang, Yumeng, Ding, Youjun, Wang, Beizhi, Ji, Qian, Peng, Chen, and Tan, Qian
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DIABETES complications ,WOUND healing ,INFLAMMATION ,APOPTOSIS ,HEMOSTASIS ,NEUTROPHILS ,CELL proliferation ,EXTRACELLULAR space ,WOUNDS & injuries ,CELL death - Abstract
Wound healing is an extremely complex process involving multiple levels of cells and tissues. It is mainly completed through four stages: haemostasis, inflammation, proliferation, and remodelling. When any one of these stages is impaired, it may lead to delayed healing or even transformation into chronic refractory wounds. Diabetes is a kind of common metabolic disease that affects approximately 500 million people worldwide, 25% of whom develop skin ulcers that break down repeatedly and are difficult to heal, making it a growing public health problem. Neutrophils extracellular traps and ferroptosis are new types of programmed cell death identified in recent years and have been found to interact with diabetic wounds. In this paper, the normal wound healing and interfering factors of the diabetic refractory wound were outlined. The mechanism of two kinds of programmed cell death was also described, and the interaction mechanism between different types of programmed cell death and diabetic refractory wounds was discussed. [ABSTRACT FROM AUTHOR]
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- 2023
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3. YAP/TAZ: Molecular pathway and disease therapy.
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Wei, Yuzi, Hui, Victoria Lee Zhi, Chen, Yilin, Han, Ruiying, Han, Xianglong, and Guo, Yongwen
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GENE regulatory networks ,CARRIER proteins ,EPIGENETICS ,CELL proliferation ,MYOFIBROBLASTS - Abstract
The Yes‐associated protein and its transcriptional coactivator with PDZ‐binding motif (YAP/TAZ) are two homologous transcriptional coactivators that lie at the center of a key regulatory network of Hippo, Wnt, GPCR, estrogen, mechanical, and metabolism signaling. YAP/TAZ influences the expressions of downstream genes and proteins as well as enzyme activity in metabolic cycles, cell proliferation, inflammatory factor expression, and the transdifferentiation of fibroblasts into myofibroblasts. YAP/TAZ can also be regulated through epigenetic regulation and posttranslational modifications. Consequently, the regulatory function of these mechanisms implicates YAP/TAZ in the pathogenesis of metabolism‐related diseases, atherosclerosis, fibrosis, and the delicate equilibrium between cancer progression and organ regeneration. As such, there arises a pressing need for thorough investigation of YAP/TAZ in clinical settings. In this paper, we aim to elucidate the signaling pathways that regulate YAP/TAZ and explore the mechanisms of YAP/TAZ‐induce diseases and their potential therapeutic interventions. Furthermore, we summarize the current clinical studies investigating treatments targeting YAP/TAZ. We also address the limitations of existing research on YAP/TAZ and propose future directions for research. In conclusion, this review aims to provide fresh insights into the signaling mediated by YAP/TAZ and identify potential therapeutic targets to present innovative solutions to overcome the challenges associated with YAP/TAZ. [ABSTRACT FROM AUTHOR]
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- 2023
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4. Application of stem cells in regeneration medicine.
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Jin, Ye, Li, Shuangyang, Yu, Qixuan, Chen, Tianli, and Liu, Da
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STEM cells ,INFLAMMATION ,CELL proliferation ,TISSUE remodeling ,BIOAVAILABILITY - Abstract
Regeneration is a complex process affected by many elements independent or combined, including inflammation, proliferation, and tissue remodeling. Stem cells is a class of primitive cells with the potentiality of differentiation, regenerate with self‐replication, multidirectional differentiation, and immunomodulatory functions. Stem cells and their cytokines not only inextricably linked to the regeneration of ectodermal and skin tissues, but also can be used for the treatment of a variety of chronic wounds. Stem cells can produce exosomes in a paracrine manner. Stem cell exosomes play an important role in tissue regeneration, repair, and accelerated wound healing, the biological properties of which are similar with stem cells, while stem cell exosomes are safer and more effective. Skin and bone tissues are critical organs in the body, which are essential for sustaining life activities. The weak repairing ability leads a pronounced impact on the quality of life of patients, which could be alleviated by stem cell exosomes treatment. However, there are obstacles that stem cells and stem cells exosomes trough skin for improved bioavailability. This paper summarizes the applications and mechanisms of stem cells and stem cells exosomes for skin and bone healing. We also propose new ways of utilizing stem cells and their exosomes through different nanoformulations, liposomes and nanoliposomes, polymer micelles, microspheres, hydrogels, and scaffold microneedles, to improve their use in tissue healing and regeneration. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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5. Retraction: Silencing of Prrx1b suppresses cellular proliferation, migration, invasion and epithelial–mesenchymal transition in triple‐negative breast cancer.
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TRIPLE-negative breast cancer ,EPITHELIAL-mesenchymal transition ,CELL proliferation ,CHROMOSOME duplication - Abstract
Zhi‐Dong Lv, Zhao‐Chuan Yang, Xiang‐Ping Liu, Li‐Ying Jin, Qian Dong, Hui‐Li Qu, Fu‐Nian Li, Bin Kong, Jiao Sun, Jiao‐Jiao Zhao, Hai‐Bo Wang, Silencing of Prrx1b suppresses cellular proliferation, migration, invasion and epithelial–mesenchymal transition in triple‐negative breast cancer. Journal of Cellular and Molecular Medicine, 20: 1640–1650. https://doi.org/10.1111/jcmm.12856 The above article, published online on 29 March 2016 in Wiley Online Library (wileyonlinelibrary.com), has been retracted by agreement between the authors, the journal Editor‐in‐Chief, Stefan Constantinescu, The Foundation for Cellular and Molecular Medicine and John Wiley and Sons Ltd. In 2022, the authors asked to retract the article as they found that some images were mistakenly duplicated from their previously published papers. Subsequently, an investigation into concerns raised by a third party, revealed inappropriate duplications of image panels within the article (Figures 2A,B and 4D) as well as between this (Figure 1B) and three other articles (with the same first or corresponding author) that were published previously in a different scientific context. Due to the number and the level of errors identified in the published figures, the editors consider the conclusions of this manuscript substantially compromised. Although the authors initially asked for the retraction, they did not agree to the retraction wording. [ABSTRACT FROM AUTHOR]
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- 2024
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6. The adaptive strategies of cells in the face of CIN.
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Storchová, Zuzana
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CHROMOSOME segregation ,CELL proliferation - Abstract
An increased frequency of chromosome segregation errors, known as chromosomal instability (CIN), leads to accumulation of aneuploid cells with abnormal chromosomal numbers, which impairs viability through negative effects on survival and proliferation under most conditions. Two recent papers find by independent approaches that the key to surviving high levels of CIN is reducing the instability itself, showcasing the remarkable adaptability of the chromosome segregation machinery, in particular the microtubule–kinetochore interface, and highlighting the crucial role that maintaining chromosomal stability plays in cell proliferation. [ABSTRACT FROM AUTHOR]
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- 2023
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7. AM3, a natural glycoconjugate, induces the functional maturation of human dendritic cells
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Martín-Vilchez, S., Molina-Jiménez, Francisca, Alonso-Lebrero, José Luis, Sanz-Cameno, P., Rodríguez-Muñoz, Y., Benedicto, Ignacio, Roda-Navarro, P., Trapero, M., Aragoneses-Fenoll, Laura, González, Salvador, Pivel, J.P., Corbí, Angel L., López Cabrera, Manuel, Moreno-Otero, R., and Majano, P.L.
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Calcium Phosphates ,hepatitis C virus ,T-Lymphocytes ,Blotting, Western ,Glycopeptides ,chemical and pharmacologic phenomena ,Enzyme-Linked Immunosorbent Assay ,Middle Aged ,Flow Cytometry ,immunomodulation ,Research Papers ,Hepatitis C ,Toll-Like Receptor 4 ,Adjuvants, Immunologic ,Gene Expression Regulation ,Humans ,Receptors, Chemokine ,dendritic cells ,Chemokines ,Aged ,Cell Proliferation ,glycoconjugate - Abstract
11 páginas, 8 figuras, 1 tabla -- PAGS nros. 698-708, Background and purpose: Dendritic cells (DCs) are dedicated antigen-presenting cells able to initiate specific immune responses and their maturation is critical for the induction of antigen-specific T-lymphocyte responses. Here, we have investigated the effects of Inmunoferon-active principle (AM3), the active agent of a commercial immunomodulatory drug, on human monocyte-derived DCs (MDDCs). Experimental approach: MDDCs derived from healthy and hepatitis C virus (HCV)-infected patients were stimulated with AM3. We analysed the expression of cell surface proteins by flow cytometry, that of cytokine production by ELISA, and the expression of chemokines and chemokine receptors by RNase protection assays. T-lymphocyte proliferation was assessed in mixed lymphocyte reactions, protein expression by western blot and luciferase-based reporter methods, and Toll-like receptor (TLR)-blocking antibodies were employed to analyse TLR activity. Key results: In MDDCs, AM3 induced or enhanced expression of CD54, CD83, CD86, HLA-DR, chemokines and chemokine receptors, interleukin (IL)-12p70 and IL-10. Furthermore, AM3 stimulated MDDCs to increase proliferation of allogenic T cells. AM3 triggered nuclear translocation of NF-κB and phosphorylation of p38 mitogen-activated protein kinase. AM3 promoted NF-κB activation in a TLR-4-dependent manner, and blocking TLR-4 activity attenuated the enhanced expression of CD80, CD83 and CD86 induced by AM3. AM3 enhanced the expression of maturation-associated markers in MDDCs from HCV-infected patients and increased the proliferation of T lymphocytes induced by these MDDCs. Conclusions and implications: These results underline the effects of AM3 in promoting maturation of MDDCs and suggest that AM3 might be useful in regulating immune responses in pathophysiological situations requiring DC maturation, This work was supported in part by Grants from Industrial Farmacéutica Cantabria (IFC), from CIBER-EHD to Dr R Moreno and Dr M López-Cabrera, from the Ministerio de Educación y Ciencia SAF2007-61201 to M L-C and from the Instituto Salud Carlos III CP 03/0020 and the Ministerio de Educación y Ciencia SAF2007-60677 to Dr Pedro Majano
- Published
- 2008
8. A forceful connection: mechanoregulation of oncogenic YAP.
- Author
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Böttcher, Ralph Thomas, Sun, Zhiqi, and Fässler, Reinhard
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NUCLEAR proteins ,PROTEINS ,CELL proliferation ,ONCOGENES ,CANCER genes ,MYOCARDIN - Abstract
The Yes-associated protein ( YAP) is an important transcriptional co-activator that mediates the cellular response to mechanical and cytoskeletal cues. In two recent papers published in The EMBO Journal, Dae-Sik Lim and colleagues show how YAP activity affects cancer formation and metastasis via a crosstalk with myocardin-related transcription factors (MRTFs; Kim et al, 2017) and SKP2-dependent cell cycle progression (Jang et al, 2017). [ABSTRACT FROM AUTHOR]
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- 2017
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9. Effect of B2O3 on the structural and in vitro biological assessment of mesoporous bioactive glass nanospheres.
- Author
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Bai, Nuonan, Chen, Weirong, Luo, Lijin, Tong, Wei, Wen, Cuilian, Zhan, Xuan, and Sa, Baisheng
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BIOACTIVE glasses ,PERIODONTAL ligament ,SOL-gel processes ,MOLECULAR dynamics ,BODY fluids ,CELL proliferation - Abstract
In this paper, the boron‐containing mesoporous bioactive glass (MBG) nanospheres have been successfully synthesized by modified sol‐gel method assisted by surfactant, and the effect of boron substitution on structure and bioactivity was evaluated by combining experiments and ab initio molecular dynamics (AIMD) simulations. All of the samples exhibit regularly uniform mesoporous spherical microstructure with an average size of about 60 nm, and the boron‐containing MBGs show higher specific surface area with the value up to 416.20 m2/g. The simulated body fluid (SBF) immersion test confirms that the deposited hydroxyapatite (HA) evidently increases with the increasing of boron content, indicating that the biological behavior has been significantly improved resulting from incorporation of boron. Additionally, our results also reveal that B2O3 substitution has positive impact on cell proliferation of human periodontal ligament cells (hPDLCs) at lower extracted concentration. Furthermore, AIMD simulation is employed to understand the relationship between structural changes and in vitro bioactivity in terms of structural information, especially the boron coordination number. The results illustrate that the boron‐containing MBG nanospheres with excellent bioactivity are great potential for biomedical applications. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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10. Advances in IKBKE as a potential target for cancer therapy.
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Yin, Min, Wang, Xin, and Lu, Jie
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DRUG resistance in cancer cells ,CANCER treatment ,NF-kappa B ,CANCER ,CELL proliferation ,METABOLIC disorders - Abstract
IKBKE (inhibitor of nuclear factor kappa‐B kinase subunit epsilon), a member of the nonclassical IKK family, plays an important role in the regulation of inflammatory reactions, activation and proliferation of immune cells, and metabolic diseases. Recent studies have demonstrated that IKBKE plays a crucial regulatory role in malignant tumor development. In recent years, IKBKE, an important oncoprotein in several kinds of tumors, has been widely found to regulate a variety of cytokines and signaling pathways. IKBKE promotes the growth, proliferation, invasion, and drug resistance of various cancers. This paper makes a detailed review that focuses on the recent discoveries of IKBKE in the malignant tumors, and puts forward that IKBKE is becoming an important therapeutic target for clinical treatment, which has been more and more realized. [ABSTRACT FROM AUTHOR]
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- 2020
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11. PagARGOS promotes low‐lignin wood formation in poplar.
- Author
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Yao, Xiaomin, Zhang, Guifang, Zhang, Geng, Sun, Qian, Liu, Cuimei, Chu, Jinfang, Jing, Yanping, Niu, Shihui, Fu, Chunxiang, Lew, Tedrick Thomas Salim, Lin, Jinxing, and Li, Xiaojuan
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WOOD ,POPLARS ,EUROPEAN aspen ,WOOD chemistry ,GENETIC overexpression ,BIOMASS production ,CELL division - Abstract
Summary: Wood formation, which occurs mainly through secondary xylem development, is important not only for supplying raw material for the 'ligno‐chemical' industry but also for driving the storage of carbon. However, the complex mechanisms underlying the promotion of xylem formation remain to be elucidated. Here, we found that overexpression of Auxin‐Regulated Gene involved in Organ Size (ARGOS) in hybrid poplar 84 K (Populus alba × Populus tremula var. glandulosa) enlarged organ size. In particular, PagARGOS promoted secondary growth of stems with increased xylem formation. To gain further insight into how PagARGOS regulates xylem development, we further carried out yeast two‐hybrid screening and identified that the auxin transporter WALLS ARE THIN1 (WAT1) interacts with PagARGOS. Overexpression of PagARGOS up‐regulated WAT1, activating a downstream auxin response promoting cambial cell division and xylem differentiation for wood formation. Moreover, overexpressing PagARGOS caused not only higher wood yield but also lower lignin content compared with wild‐type controls. PagARGOS is therefore a potential candidate gene for engineering fast‐growing and low‐lignin trees with improved biomass production. [ABSTRACT FROM AUTHOR]
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- 2024
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12. Deletion of endothelial IGFBP5 protects against ischaemic hindlimb injury by promoting angiogenesis.
- Author
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Song, Fei, Hu, Yu, Hong, Yi‐Xiang, Sun, Hu, Han, Yue, Mao, Yi‐Jie, Wu, Wei‐Yin, Li, Gang, and Wang, Yan
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INSULIN-like growth factor-binding proteins ,SOMATOMEDIN ,NEOVASCULARIZATION ,VASCULAR remodeling ,HINDLIMB - Abstract
Background: Angiogenesis is critical for forming new blood vessels from antedating vascular vessels. The endothelium is essential for angiogenesis, vascular remodelling and minimisation of functional deficits following ischaemia. The insulin‐like growth factor (IGF) family is crucial for angiogenesis. Insulin‐like growth factor‐binding protein 5 (IGFBP5), a binding protein of the IGF family, may have places in angiogenesis, but the mechanisms are not yet completely understood. We sought to probe whether IGFBP5 is involved in pathological angiogenesis and uncover the molecular mechanisms behind it. Methods and results: IGFBP5 expression was elevated in the vascular endothelium of gastrocnemius muscle from critical limb ischaemia patients and hindlimb ischaemic (HLI) mice and hypoxic human umbilical vein endothelial cells (HUVECs). In vivo, loss of endothelial IGFBP5 (IGFBP5EKO) facilitated the recovery of blood vessel function and limb necrosis in HLI mice. Moreover, skin damage healing and aortic ring sprouting were faster in IGFBP5EKO mice than in control mice. In vitro, the genetic inhibition of IGFBP5 in HUVECs significantly promoted tube formation, cell proliferation and migration by mediating the phosphorylation of IGF1R, Erk1/2 and Akt. Intriguingly, pharmacological treatment of HUVECs with recombinant human IGFBP5 ensued a contrasting effect on angiogenesis by inhibiting the IGF1 or IGF2 function. Genetic inhibition of IGFBP5 promoted cellular oxygen consumption and extracellular acidification rates via IGF1R‐mediated glycolytic adenosine triphosphate (ATP) metabolism. Mechanistically, IGFBP5 exerted its role via E3 ubiquitin ligase Von Hippel‐Lindau (VHL)‐regulated HIF1α stability. Furthermore, the knockdown of the endothelial IGF1R partially abolished the reformative effect of IGFBP5EKO mice post‐HLI. Conclusion: Our findings demonstrate that IGFBP5 ablation enhances angiogenesis by promoting ATP metabolism and stabilising HIF1α, implying IGFBP5 is a novel therapeutic target for treating abnormal angiogenesis‐related conditions. [ABSTRACT FROM AUTHOR]
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- 2024
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13. Joint modeling of tumor dynamics and progression‐free survival in advanced breast cancer: Leveraging data from amcenestrant early phase I–II trials.
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Cerou, Marc, Thai, Hoai‐Thu, Deyme, Laure, Fliscounakis‐Huynh, Sophie, Comets, Emmanuelle, Cohen, Patrick, Cartot‐Cotton, Sylvaine, and Veyrat‐Follet, Christine
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METASTATIC breast cancer ,PROGRESSION-free survival ,BREAST ,TUMOR growth ,CELL proliferation ,TUMORS ,VALIDITY of statistics - Abstract
A joint modeling framework was developed using data from 75 patients of early amcenestrant phase I–II AMEERA‐1‐2 dose escalation and expansion cohorts. A semi‐mechanistic tumor growth inhibition (TGI) model was developed. It accounts for the dynamics of sensitive and resistant tumor cells, an exposure‐driven effect on tumor proliferation of sensitive cells, and a delay in the initiation of treatment effect to describe the time course of target lesion tumor size (TS) data. Individual treatment exposure overtime was introduced in the model using concentrations predicted by a population pharmacokinetic model of amcenestrant. This joint modeling framework integrated complex RECISTv1.1 criteria information, linked TS metrics to progression‐free survival (PFS), and was externally evaluated using the randomized phase II trial AMEERA‐3. We demonstrated that the instantaneous rate of change in TS (TS slope) was an important predictor of PFS and the developed joint model was able to predict well the PFS of amcenestrant phase II monotherapy trial using only early phase I–II data. This provides a good modeling and simulation tool to inform early development decisions. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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14. Use of aspirin in the prevention of colorectal cancer through TIGIT‐CD155 pathway.
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Ma, Bin, Duan, Xiangguo, Zhou, Qiunan, Liu, Juanxi, Yang, Xiaojuan, Zhang, Dong, Yang, Shaoqi, Du, Yong, Li, Hai, and Su, Chunxia
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ASPIRIN ,COLORECTAL cancer ,CANCER prevention ,PROGRAMMED cell death 1 receptors ,T cell receptors ,CANCER cell proliferation ,CANCER cell migration - Abstract
Colorectal cancer (CRC) is one of the most widespread malignant cancers, with a high incidence and mortality all over the world. Aspirin (ASA) otherwise known as acetylsalicylic acid, is a non‐steroidal anti‐inflammatory drug that has shown promising results in the prevention of chronic diseases, including several cancers. In previous studies, aspirin has been shown to reduce the incidence of CRC. Immune checkpoint blockade of T cell Ig and ITIM domain receptor (TIGIT) alone or combined with other immune checkpoint blockades moleculars has gained impressive results in the treatment of the melanoma and glioblastoma. Here, we found that TIGIT and Poliovirus receptor (PVR, CD155) are expressed in tumour cells; the TIGIT and CD155 protein expression in cancer tissue has been found to be significantly higher than that in the precancerous tissue. T cell Ig and ITIM domain receptor and CD226 were expressed in the lymphocytes near the tumour tissue and the adjacent tissues. Aspirin has been found to inhibit cancer cell viability and promote CRC cell apoptosis.Similarly, aspirin has also been found to increase pro‐apoptotic protein Bax's expression. We found that the expression of TIGIT decreased with an increase in the concentration of aspirin and that the suppression of TIGIT can affect the effect of aspirin on cell proliferation. In this paper, we found that aspirin attenuates cancer cell proliferation and induces CRC cells apoptosis by down‐regulating the expression of TIGIT, which provides new evidence for the application of aspirin in cancer treatment. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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15. MCLPMDA: A novel method for miRNA‐disease association prediction based on matrix completion and label propagation.
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Yu, Sheng‐Peng, Liang, Cheng, Xiao, Qiu, Li, Guang‐Hui, Ding, Ping‐Jian, and Luo, Jia‐Wei
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MICRORNA ,CELL proliferation ,MEDICAL care ,GENE expression ,APOPTOSIS - Abstract
MiRNAs are a class of small non‐coding RNAs that are involved in the development and progression of various complex diseases. Great efforts have been made to discover potential associations between miRNAs and diseases recently. As experimental methods are in general expensive and time‐consuming, a large number of computational models have been developed to effectively predict reliable disease‐related miRNAs. However, the inherent noise and incompleteness in the existing biological datasets have inevitably limited the prediction accuracy of current computational models. To solve this issue, in this paper, we propose a novel method for miRNA‐disease association prediction based on matrix completion and label propagation. Specifically, our method first reconstructs a new miRNA/disease similarity matrix by matrix completion algorithm based on known experimentally verified miRNA‐disease associations and then utilizes the label propagation algorithm to reliably predict disease‐related miRNAs. As a result, MCLPMDA achieved comparable performance under different evaluation metrics and was capable of discovering greater number of true miRNA‐disease associations. Moreover, case study conducted on Breast Neoplasms further confirmed the prediction reliability of the proposed method. Taken together, the experimental results clearly demonstrated that MCLPMDA can serve as an effective and reliable tool for miRNA‐disease association prediction. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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16. Naphthalene diimide‐derivatives G‐quadruplex ligands induce cell proliferation inhibition, mild telomeric dysfunction and cell cycle perturbation in U251MG glioma cells.
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Muoio, Daniela, Berardinelli, Francesco, Leone, Stefano, Coluzzi, Elisa, di Masi, Alessandra, Doria, Filippo, Freccero, Mauro, Sgura, Antonella, Folini, Marco, and Antoccia, Antonio
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NAPHTHALENE derivatives ,LIGANDS (Biochemistry) ,CELL proliferation ,TELOMERASE ,CELL cycle ,GLIOMAS - Abstract
In the present paper, the biological effects of three different naphthalene diimides (NDIs) G‐quadruplex (G4) ligands (H‐NDI‐Tyr, H‐NDI‐NMe2, and tetra‐NDI‐NMe2) were comparatively evaluated to those exerted by RHPS4, a well‐characterized telomeric G4‐ligand, in an in vitro model of glioblastoma. Data indicated that NDIs were very effective in blocking cell proliferation at nanomolar concentrations, although displaying a lower specificity for telomere targeting compared to RHPS4. In addition, differently from RHPS4, NDIs failed to enhance the effect of ionizing radiation, thus suggesting that additional targets other than telomeres could be involved in the strong NDI‐mediated anti‐proliferative effects. In order to test telomeric off‐target action of NDIs, a panel of genes involved in tumor progression, DNA repair, telomere maintenance, and cell‐cycle regulation were evaluated at transcriptional and translational level. Specifically, the compounds were able to cause a marked reduction of TERT and BCL2 amounts as well as to favor the accumulation of proteins involved in cell cycle control. A detailed cytofluorimetric analysis of cell cycle progression by means of bromodeoxyuridine (BrdU) incorporation and staining of phospho‐histone H3 indicated that NDIs greatly reduce the progression through S‐phase and lead to G1 accumulation of BrdU‐positive cells. Taken together, these data indicated that, besides effects on telomeres and oncogenes such as Tert and Bcl2, nanomolar concentrations of NDIs determined a sustained block of cell proliferation by slowing down cell cycle progression during S‐phase. In conclusion, our data indicate that NDIs G4‐ligands are powerful antiproliferative agents, which act through mechanisms that ultimately lead to altered cell‐cycle control. The effect of different telomeric G‐quadruplex (G4) ligands (three naphthalene diimides (NDIs) derivatives and RHPS4), were comparatively evaluated in radio‐resistant U251MG glioblastoma cells. Although displaying a lower than RHPS4 specificity for telomeric G4 and absence of radio‐sensitization potential, NDIs were very effective in blocking cell proliferation through the deregulation of proteins involved in cell‐cycle control and the slow‐down of cell‐cycle progression through the S phase. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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17. Generating anatomical variation through mutations in networks - implications for evolution.
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Bard, Jonathan
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GENETIC mutation ,ANIMAL genetics ,CELL proliferation ,APOPTOSIS ,CELL differentiation ,GENETIC regulation - Abstract
Genetic mutation leads to anatomical variation only indirectly because many proteins involved in generating anatomical structures in embryos operate cooperatively within molecular networks. These include gene-regulatory or control networks ( CNs) for timing, signaling and patterning together with the process networks ( PNs) for proliferation, apoptosis, differentiation and morphogenesis that they control. This paper argues that anatomical variation is achieved through a two-stage process: mutation alters the outputs of CNs and perhaps the proliferation network, and such changed outputs alter the ways that PNs construct tissues. This systems-biology approach has several implications: first, because networks contain many cooperating proteins, they amplify the effects of genetic variation so enabling mutation to generate a wider range of phenotypes than a single changed protein acting alone could. Second, this amplification helps explain how novel phenotypes can be produced relatively rapidly. Third, because even organisms with novel anatomical phenotypes derive from variants in standard networks, there is no genetic barrier to their producing viable offspring. This approach also clarifies a terminological difficulty: classical evolutionary genetics views genes in terms of phenotype heritability rather than as DNA sequences. This paper suggests that the molecular phenotype of the classical concept of a gene is often a protein network, with a mutation leading to an alteration in that network's dynamics. [ABSTRACT FROM AUTHOR]
- Published
- 2014
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18. AFAP1-AS1: A novel oncogenic long non-coding RNA in human cancers.
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Fuyou Zhang, Jianfa Li, Huizhong Xiao, Yifan Zou, Yuchen Liu, and Weiren Huang
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NON-coding RNA ,NUCLEOTIDES ,CELL proliferation ,APOPTOSIS ,ANTISENSE RNA ,ESOPHAGEAL cancer - Abstract
Long non-coding RNAs (lncRNAs), a group of non-protein- coding RNAs with more than 200 nucleotides in length, are involved in multiple biological processes, such as the proliferation, apoptosis, migration and invasion. Moreover, numerous studies have shown that lncRNAs play important roles as oncogenes or tumour suppressor genes in human cancers. In this paper, we concentrate on actin filament-associated protein 1-antisense RNA 1 (AFAP1-AS1), a well-known long non-coding RNA that is overexpressed in various tumour tissues and cell lines, including oesophageal cancer, pancreatic ductal adenocarcinoma, nasopharyngeal carcinoma, lung cancer, hepatocellular carcinoma, ovarian cancer, colorectal cancer, biliary tract cancer and gastric cancer. Moreover, high expression of AFAP1-AS1 was associated with the clinicopathological features and cancer progression. In this review, we sum up the current studies on the characteristics of AFAP1-AS1 in the biological function and mechanism of human cancers. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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19. Correction to "Curcumin induces ferroptosis in non‐small‐cell lung cancer via activating autophagy".
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AUTOPHAGY ,APOPTOSIS ,CANCER patient medical care ,CELL proliferation ,CURCUMIN ,LUNG cancer - Published
- 2024
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20. Circ‐POSTN promotes the progression and reduces radiosensitivity in esophageal cancer by regulating the miR‐876‐5p/FYN axis.
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Chu, Alan, Sun, Chen, Liu, Zongwen, Liu, Shijia, Li, Mengxi, Song, Rui, Gan, Lanlan, Wang, Yongtai, and Fan, Ruitai
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FLOW cytometry ,BIOLOGICAL models ,RESEARCH funding ,MICRORNA ,CIRCULAR RNA ,CELL proliferation ,APOPTOSIS ,POLYMERASE chain reaction ,PERIOSTIN ,ESOPHAGEAL tumors ,IN vivo studies ,XENOGRAFTS ,MICE ,WESTERN immunoblotting ,ANIMAL experimentation ,BIOLOGICAL assay ,DISEASE progression ,PRECIPITIN tests - Abstract
Background: Circular RNAs (circRNAs) play critical roles in the tumorigenesis and radiosensitivity of multiple cancers. Nevertheless, the biological functions of circRNA periostin (circ‐POSTN) in esophageal cancer (EC) progression and radiosensitivity have not been well elucidated. Methods: The expression of circ‐POSTN, microRNA‐876‐5p (miR‐876‐5p), and proto‐oncogene tyrosine‐protein kinase (FYN) was analyzed by quantitative reverse transcription PCR (RT‐qPCR). Cell proliferation was assessed by MTT, colony formation, and 5‐ethynyl‐2′‐deoxyuridine (EDU) assays. All protein levels were detected by western blot assay. Cell apoptosis and invasion were assessed by flow cytometry analysis and transwell assay, respectively. Dual‐luciferase reporter and RNA immunoprecipitation (RIP) assays were used to validate the interaction between miR‐876‐5p and circ‐POSTN or FYN. The role of circ‐POSTN in vivo was explored by establishing mice xenograft model. Results: Circ‐POSTN was overexpressed in EC tissues and cells. Knockdown of circ‐POSTN inhibited cell proliferation and invasion and elevated apoptosis and radiosensitivity in EC cells. MiR‐876‐5p was a direct target of circ‐POSTN, and its knockdown reversed the role of sh‐circ‐POSTN in EC cells. FYN was a direct target of miR‐876‐5p, and FYN elevation weakened the effects of miR‐876‐5p overexpression on the progression and radiosensitivity of EC cells. Moreover, circ‐POSTN acted as a miR‐876‐5p sponge to regulate FYN expression. Circ‐POSTN interference also suppressed tumor growth and enhanced radiosensitivity in vivo. Conclusion: Circ‐POSTN knockdown inhibited proliferation and invasion, but increased apoptosis and enhanced radiosensitivity in EC cells via modulating miR‐876‐5p/FYN axis, which might be a potential diagnostic and therapeutic target for EC. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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21. Exosomal miR‐1470 is a diagnostic biomarker and promotes cell proliferation and metastasis in colorectal cancer.
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Wu, Yawen, Zhang, Jie, Lin, Fanfeng, Zhao, Yajing, Zheng, Baibing, Zhou, Na, Zhang, Zhe, Li, Guanghao, and Xie, Li
- Subjects
COLORECTAL cancer ,EXOSOMES ,RECEIVER operating characteristic curves ,CELL proliferation ,BIOMARKERS - Abstract
Background: In recent years,the lack of specific markers for the diagnosis of colorectal cancer has led to an upward trend in both morbidity and mortality from this condition. There is an urgent need to identify molecular biomarkers that contribute to early cancer detection. This study aimed to identify specific exosomal microRNAs that hold potential as diagnostic biomarkers for CRC. Methods: We screened for differentially expressed miRNAs using the CRC exosome dataset GSE39833. To validate the results in the public database, we collected serum from 168 CRC patients and 168 healthy volunteers. The expression levels of exosomal miR‐1470 in healthy volunteers and CRC patients were analyzed using qRT‐PCR. To evaluate the diagnostic potential of the selected miR‐1470 in distinguishing CRC patients from healthy controls, we analyzed its receiver operating characteristic curve. To explore the biological functions of miR‐1470 in CRC cell lines, we detected the miR‐1470's ability to regulate the growth and metastasis of CRC cells by CCK8, transwell and other assays after transfection of miR‐1470 in SW480, HCT‐116 cells. Results: Exosomal miR‐1470 exhibited significant up‐regulation in CRC patients compared to healthy volunteers. The ROC curve analysis revealed an area under the curve (AUC) of 0.74 (95% confidence interval: 0.6876–0.7920) for exosomal miR‐1470, indicating its potential as a diagnostic biomarker. Furthermore, the expression level of miR‐1470 in CRC patients showed correlations with age, metastasis, and HDL content. We overexpressed miR‐1470 in CRC cell lines. CCK8 proliferation assay showed that miR‐1470 promoted the proliferation ability of SW480 and HCT‐116 cells. Transwell assay showed that miR‐1470 promoted the migration and invasion ability of SW480 and HCT‐116 cells. Conclusion: This suggested that non‐invasive diagnosis of CRC is possible by detecting the level of miR‐1470 in exosomes, which has important implications for early detection and treatment of this disease. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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22. Fibronectin Connecting Cell Sheet Based on Click Chemistry for Wound Repair.
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Xu, Wei, He, Meng, and Lu, Qinghua
- Subjects
WOUND healing ,CLICK chemistry ,FIBRONECTINS ,HAIR follicles ,CELL migration ,BLOOD vessels ,CELL proliferation - Abstract
As a living repair material, cell sheet exhibits significant potential in wound repair. Nonetheless, wound healing is a complicated and protracted process that necessitates specific repair functions at each stage, including hemostasis and antibacterial activity. In this work, on the basis of harvesting the cell sheet via a photothermal response strategy, a fibronectin attached cell sheet (FACS) is prepared to enhance its wound repair capability. For this purpose, the azide group (N3) is initially tagged onto the cell surface through metabolic glycoengineering of unnatural sugars, and then the conjugate (DBCO‐fibronectin) comprises of the dibenzocyclooctyne (DBCO) and fibronectin with multiple wound repair functions is linked to N3 using click chemistry. Biological evaluations following this demonstrates that the FACS preparation exhibits excellent biocompatibility, and the fibronectin modification enhances the capacity for cell proliferation and migration. Moreover, in vivo wound healing experiment confirms the reparative efficacy of FACS. It not only has a wound closure rate 1.46 times that of a conventional cell sheet but also reduces inflammatory cell infiltration, promotes hair follicle and blood vessel regeneration, and encourages collagen deposition. This strategy holds enormous clinical potential and paves the way for advanced functional modifications of cell sheets. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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23. hsa_circ_0000092 promotes hepatocellular carcinoma progression through up‐regulating HN1 expression by binding to microRNA‐338‐3p.
- Author
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Pu, Jian, Wang, Jianchu, Li, Wenchuan, Lu, Yuan, Wu, Xianjian, Long, Xidai, Luo, Chunying, and Wei, Huamei
- Subjects
HEPATOCELLULAR carcinoma ,COMPETITIVE endogenous RNA ,CIRCULAR RNA ,NORTHERN blot ,CELL proliferation - Abstract
Circular RNAs (circRNAs) have been identified in diverse cancers for their role in regulating multiple cellular processes by antagonizing microRNAs (miRNAs or miRs). However, the role of circRNA hsa_circ_0000092 in hepatocellular carcinoma (HCC) still remains enigmatic. Therefore, we aimed to investigate the specific mechanism of hsa_circ_0000092 in HCC. Differentially expressed circRNAs associated to HCC were initially analysed. The expression of hsa_circ_0000092, miR‐338‐3p and HN1 in HCC tissues and cell lines was examined. Next, the interaction among hsa_circ_0000092, miR‐338‐3p and HN1 was determined by dual‐luciferase reporter, RNA pull‐down and northern blot assays. Subsequently, a series of mimic, inhibitor or siRNA plasmids were delivered into HCC cells to validate the effects of hsa_circ_0000092, miR‐338‐3p and HN1 in controlling cell proliferation, migration, invasion and angiogenesis in vitro. Furthermore, the role of hsa_circ_0000092 in tumour growth of HCC in vivo was assessed with hsa_circ_0000092 depleted with siRNA. The hsa_circ_0000092/miR‐338‐3p/HN1 axis was predicted to participate in the development of HCC. hsa_circ_0000092 and HN1 were highly expressed while miR‐338‐3p was poorly expressed in HCC tissues and cell lines. hsa_circ_0000092 could competitively bind to miR‐338‐3p to up‐regulate HN1 expression. Moreover, depleted hsa_circ_0000092 or elevated miR‐338‐3p was shown to suppress HCC cell proliferation, migration, invasion and angiogenesis in vitro via down‐regulation of HN1. Furthermore, silencing hsa_circ_0000092 was demonstrated to suppress tumour growth in HCC in vivo. The results of this study suggested that hsa_circ_0000092 impaired miR‐338‐3p‐mediated HN1 inhibition to aggravate the development of HCC, indicating that hsa_circ_0000092 is a potential candidate marker and therapeutic target for HCC. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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24. Horizontal necklines correction with absorbable braided polydioxanone threads: Case series.
- Author
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Yi, Kyu‐Ho, Kim, Soo‐Bin, Chua, Deborah, Stefanelli, Matthieu Beustes, Alfertshofer, Michael, and Vachiramon, Vasanop
- Subjects
WRINKLES (Skin) ,BRAIDED structures ,CELL migration ,CELL proliferation ,THREAD ,FACELIFT - Abstract
Introduction: The prevalence of horizontal neck lines as a cosmetic concern is widely acknowledged, yet the available treatment options are limited, and no studies have investigated the use of polydioxanone‐barbed threads. These threads, characterized by a finely braided structure, function as a scaffold to attract regenerative factors and facilitate the migration and proliferation of cells. This study aims to evaluate the outcomes of concurrent application of braided polydioxanone‐barbed threads for addressing horizontal neck wrinkles. Methodology: A retrospective case series involving four female participants (aged 41, 43, 45, and 46) treated with polydioxanone‐barbed threads for horizontal neck wrinkles between January 2023 and July 2023 was conducted. Adult patients were assessed at an 8‐week follow‐up, revealing a significant reduction in wrinkle intensity based on the Horizontal Neck Wrinkle Severity Scale. Results: The analysis of horizontal neck lines demonstrated a notable decrease in wrinkle intensity according to the Horizontal Neck Wrinkle Severity Scale at the 8‐week mark, and this improvement maintained statistical significance. Both patient Global Aesthetic Improvement Scale (GAIS) scores (90%–100%) and physician GAIS scores (100%) were rated as excellent. Conclusion: The subdermal application of polydioxanone‐barbed threads for horizontal neck lines proves to be a secure and efficacious approach for treating horizontal neck wrinkles, with no observed Tyndall effect. This technique shows promise for rejuvenating the skin in the horizontal neckline region. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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25. CD8+ T cell infiltration and proliferation in the brainstem during experimental cerebral malaria.
- Author
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Wang, Jun, Zhu, Qinghao, Shen, Yan, Liang, Jiao, Wang, Yi, Huang, Yuxiao, Tong, Guodong, Wang, Xu, Zhang, Ningning, Yu, Kangjie, Li, Yinghui, and Zhao, Ya
- Subjects
CEREBRAL malaria ,T cells ,IMMUNE checkpoint proteins ,CELL proliferation ,BRAIN stem - Abstract
Introduction: Cerebral malaria (CM) is a lethal neuroinflammatory disease caused by Plasmodium infection. Immune cells and brain parenchyma cells contribute to the pathogenesis of CM. However, a systematic examination of the changes that occur in the brain parenchyma region during CM at the single‐cell resolution is still poorly studied. Aims: To explore cell composition and CD8+ T cell infiltration, single‐cell RNA sequencing (scRNA‐seq) was performed on the brainstems of healthy and experimental cerebral malaria (ECM) mice. Then CD8+ T cell infiltration was confirmed by flow cytometry and immunofluorescence assays. Subsequently, the characteristics of the brain‐infiltrated CD8+ T cells were analyzed. Finally, the interactions between parenchyma cells and brain‐infiltrated CD8+ T cells were studied with an astrocytes‐CD8+ T cell cocultured model. Results: The brainstem is the most severely damaged site during ECM. ScRNA‐seq revealed a large number of CD8+ T cells infiltrating into the brainstem in ECM mice. Brain‐infiltrated CD8+ T cells were highly activated according to scRNA‐seq, immunofluorescence, and flow cytometry assays. Further analysis found a subset of ki‐67+ CD8+ T cells that have a higher transcriptional level of genes related to T cell function, activation, and proliferation, suggesting that they were exposed to specific antigens presented by brain parenchyma cells. Brain‐infiltrated CD8+ T cells were the only prominent source of IFN‐γ in this single‐cell analysis. Astrocytes, which have a high interferon response, act as cross‐presenting cells to recruit and re‐activate brain‐infiltrated CD8+ T cells. We also found that brain‐infiltrated CD8+ T cells were highly expressed immune checkpoint molecule PD‐1, while parenchyma cells showed up‐regulation of PD‐L1 after infection. Conclusions: These findings reveal a novel interaction between brain‐infiltrated CD8+ T cells and parenchyma cells in the ECM brainstem, suggesting that the PD‐1/PD‐L1 signal pathway is a promising adjunctive therapeutic strategy for ECM targeting over‐activated CD8+ T cells. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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26. A simple device to rapidly prepare whole mounts of murine intestine.
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Rudling, R., Hassan, A. B., Kitau, J., Mandir, N., and Goodlad, R. A.
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LABORATORY mice ,GASTROINTESTINAL system ,TUMORS ,CANCER cells ,CELL proliferation - Abstract
Many mouse models of neoplasia and pre-neoplasia require the examination of whole mounts of the gastrointestinal tract. A simple device has been produced to facilitate the rapid preparation of mouse intestines for subsequent quantification of tumours and pre-neoplastic lesions such as aberrant crypt foci. The device greatly speeds up the production of whole mounts and also provides far more consistent and better-quality preparations. [ABSTRACT FROM AUTHOR]
- Published
- 2006
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27. Purinergic signalling.
- Author
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Burnstock, Geoffrey
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PURINES ,ADENOSINE triphosphate ,NEUROTRANSMITTERS ,NERVES ,BLADDER ,PYRIMIDINES ,BLOOD platelet aggregation ,CELL proliferation - Abstract
While there were early papers about the extracellular actions of purines, the role of ATP as a purinergic neurotransmitter in nonadrenergic, noncholinergic nerves in the gut and bladder in 1972 was a landmark discovery, although it met considerable resistance for the next 20 years. In the early 1990s, receptors for purines were cloned: four P1 receptor subtypes and seven P2X ionotropic and eight P2Y metabotropic receptor subtypes are currently recognized and characterized. The mechanisms underlying ATP release and breakdown are discussed. Purines and pyrimidines have major roles in the activities of non-neuronal cells as well as neurons. This includes fast signalling roles in exocrine and endocrine secretion, platelet aggregation, vascular endothelial cell-mediated vasodilation and nociceptive mechanosensory transduction, as well as acting as a cotransmitter and neuromodulator in most, if not all, nerve types in the peripheral and central nervous systems. More recently, slow (trophic) purinergic signalling has been implicated in cell proliferation, migration, differentiation and death in embryological development, wound healing, restenosis, atherosclerosis, ischaemia, cell turnover of epithelial cells in skin and visceral organs, inflammation, neuroprotection and cancer.British Journal of Pharmacology (2006) 147, S172–S187. doi:10.1038/sj.bjp.0706429 [ABSTRACT FROM AUTHOR]
- Published
- 2006
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28. Retracted: MicroRNA-491 and microRNA-1306 target hTERT to inhibit proliferation and invasion in ovarian cancer cells.
- Subjects
MICRORNA ,OVARIAN cancer ,CELL proliferation ,PUBLISHED articles ,ELECTRONIC publications - Abstract
The following Accepted Article from FEBS Open Bio, 'MicroRNA-491 and microRNA-1306 target hTERT to inhibit proliferation and invasion in ovarian cancer cells' by Lin Bai, Hui Wang, Ai-Hua Wang, Luo-Ying Zhang and Jie Bai, published online on 10 November 2016 in Wiley Online Library (), has been retracted by agreement between the authors, the journal Executive Editor Mary Purton and John Wiley & Sons. The retraction has been agreed due to inconsistencies in the data for miR-1306 contained in this paper with recent results in other ovarian cancer cell lines as yet unpublished. This paper has been withdrawn until further confirmatory experiments are carried out. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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29. Protein kinase Cδ promotes proliferation and induces malignant transformation in skeletal muscle.
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Czifra G, Szöllősi A, Nagy Z, Boros M, Juhász I, Kiss A, Erdődi F, Szabó T, Kovács I, Török M, Kovács L, Blumberg PM, and Bíró T
- Subjects
- Animals, Cell Line, Tumor, Cells, Cultured, Humans, Mice, Cell Proliferation physiology, Cell Transformation, Neoplastic metabolism, Cell Transformation, Neoplastic pathology, Muscle, Skeletal metabolism, Protein Kinase C-delta metabolism
- Abstract
In this paper, we investigated the isoform-specific roles of certain protein kinase C (PKC) isoforms in the regulation of skeletal muscle growth. Here, we provide the first intriguing functional evidence that nPKCδ (originally described as an inhibitor of proliferation in various cells types) is a key player in promoting both in vitro and in vivo skeletal muscle growth. Recombinant overexpression of a constitutively active nPKCδ in C2C12 myoblast increased proliferation and inhibited differentiation. Conversely, overexpression of kinase-negative mutant of nPKCδ (DN-nPKCδ) markedly inhibited cell growth. Moreover, overexpression of nPKCδ also stimulated in vivo tumour growth and induced malignant transformation in immunodeficient (SCID) mice whereas that of DN-nPKCδ suppressed tumour formation. The role of nPKCδ in the formation of rhabdomyosarcoma was also investigated where recombinant overexpression of nPKCδ in human rhabdomyosarcoma RD cells also increased cell proliferation and enhanced tumour formation in mouse xenografts. The other isoforms investigated (PKCα, β, ε) exerted only minor (mostly growth-inhibitory) effects in skeletal muscle cells. Collectively, our data introduce nPKCδ as a novel growth-promoting molecule in skeletal muscles and invite further trials to exploit its therapeutic potential in the treatment of skeletal muscle malignancies., (© 2015 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.)
- Published
- 2015
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30. The T-cell response to haptenated insulins II. THE ANTIBODY RESPONSE.
- Author
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Florys, M., Wallace, G.R., Oettel, K., and Chain, B.M.
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T cells ,INSULIN ,IMMUNOGLOBULINS ,LYMPHOCYTES ,GLYCINE ,CELL proliferation - Abstract
As described in an accompanying paper, trinitrophenyl (TNP) modification of pork insulin (PI) at the A1 glycine position allows this molecule to stimulate a proliferative response in H-2
b (B10) mice. We now show that this antigen stimulates low IgG responses in the same strain of mice. Our results show that T-cell help and proliferation may therefore be regulated independently. [ABSTRACT FROM AUTHOR]- Published
- 1989
31. Delineation of two defects responsible for T-cell hyporesponsiveness to concanavalin A in MRL congenic mice.
- Author
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Cameron, R. and Waterfield, J. D.
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T cells ,IMMUNOGLOBULINS ,CELL proliferation ,MICE ,GENETICS ,CYTOLOGY - Abstract
MRL-lpr mice and their congenic counterparts MRL- + spontaneously develop an autoimmune disease that resembles systemic lupus erythematosus in humans. The two strains, although congenic, differ by a considerable number of disease parameters, reflecting the expression of the lpr autosomal recessive gene. One paradox that has developed out of the work utilizing the congenic mice is that the gene responsible for lymphoproliferation also appears to be responsible for the inability of T cells to respond to proliferative signals in vitro. In this paper we investigated a possible lpr gene-encoded macrophage defect in these mice. It was found, however, that both the MRL- + and MRL-lpr mice failed to divide in response to Con A, the lack of division correlating with an inability to secrete the growth promoter interleukin-2. In MRL- + mice and young MRL-lpr mice this non-responsiveness was corrected by the addition of normal CRA PEC. The defect could not be explained by a failure of M RL- + or M RL-lpr peritoneal exudate cells to quantitatively or qualitatively provide a source of interleukin-1 to Con A-activated T cells or by the possibility that the peritoneal exudate cells were blocked in their function by the presence of sera-derived autoantibodies and/or immune complexes on their membranes. We postulate that the inability of T cells to proliferate in MRL congenic mice can be explained by two defects: (i) the failure of antigen-presenting cells in MRL- + and MRL-lpr to provide the necessary signals to immunocompetent T cells, this defect not being associated with the lpr gene, and (ii) the lpr gene controlled outgrowth of a unique T-cell population that cannot respond in our assay system. [ABSTRACT FROM AUTHOR]
- Published
- 1986
32. Quercetin and its derivatives for wound healing in rats/mice: Evidence from animal studies and insight into molecular mechanisms.
- Author
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Huang, He‐chen, Chen, Yan, Hu, Jie, Guo, Xiu‐tian, Zhou, Shao‐rong, Yang, Qi‐qi, Du, Yu‐qing, Jin, Yu, Liu, Guo‐bin, and Peng, Yun‐hua
- Subjects
WOUND healing ,ONLINE information services ,INTERLEUKINS ,COLLAGEN ,MEDICAL information storage & retrieval systems ,META-analysis ,FIBROBLASTS ,ANIMAL experimentation ,SYSTEMATIC reviews ,NEOVASCULARIZATION ,INFLAMMATION ,QUERCETIN ,RESEARCH funding ,CELL proliferation ,WOUNDS & injuries ,MEDLINE ,DATA analysis software ,VASCULAR endothelial growth factors ,MICE - Abstract
Aimed to clarify the effect of quercetin and its derivatives on wound healing in animal experiments. PubMed, Embase, Science Direct, Web of Science, SinoMed, Vip Journal Integration Platform, China National Knowledge Infrastructure and WanFang databases were searched for animal experiments investigating the effect of quercetin and its derivatives on wound healing to April 2023. The Review Manager 5.4 software was used to conduct meta‐analysis. Eighteen studies were enrolled in this article. According to the SYRCLE's RoB tool assessment, these studies exposed relatively low methodological quality. It was shown that animals with cutaneous wound receiving quercetin had faster wound healing in wound closure (%) than the control group. Moreover, the difference in efficacy gradually emerged after third day (WMD = 7.13 [5.52, 8.74]), with a peak reached on the tenth day after wounding (WMD = 19.78 [17.82, 21.74]). Subgroup analysis revealed that quercetin for wound closure (%) was independent of the types of rats and mice, wound area and with or without diabetes. Clear conclusion was also shown regarding the external application of quercetin for wound healing (WMD = 17.77 [11.11, 24.43]). A significant reduction in the distribution of inflammatory cells occurred in the quercetin group. Quercetin could increase blood vessel density (WMD = 1.85 [0.68, −3.02]), fibroblast distribution and collagen fraction. Biochemical indicators, including IL‐1β, IL‐10, TNF‐α, TGF‐β, vascular endothelial growth factor (VEGF), hydroxyproline and alpha‐smooth muscle actin (α‐SMA), had the consistent results. Quercetin and its derivatives could promote the recovery of cutaneous wound in animals, through inhibiting inflammatory response and accelerating angiogenesis, proliferation of fibroblast and collagen deposition. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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33. Polarity reversal of canine intestinal organoids reduces proliferation and increases cell death.
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Csukovich, Georg, Wagner, Maximilian, Walter, Ingrid, Burger, Stefanie, Tschulenk, Waltraud, Steinborn, Ralf, Pratscher, Barbara, and Burgener, Iwan Anton
- Subjects
CELL death ,CELL proliferation ,ORGANOIDS ,IMMUNOSTAINING ,INTESTINES - Abstract
Apical‐out intestinal organoids are a relatively simple method of gaining access to the apical cell surface and have faced increasing scientific interest over the last few years. Apical‐out organoids can thus be used for disease modelling to compare differing effects on the basolateral versus the apical cell surface. However, these 'inside‐out' organoids die relatively quickly and cannot be propagated as long as their basal‐out counterparts. Here, we show that apical‐out organoids have drastically reduced proliferative potential, as evidenced by immunohistochemical staining and the incorporation of the thymidine analogue EdU. At the same time, cell death levels are increased. Nevertheless, these phenomena cannot be explained by an induction of differentiation, as the gene expression of key marker genes for various cell types does not change over time. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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34. Urethral Microenvironment Adapted Sodium Alginate/Gelatin/Reduced Graphene Oxide Biomimetic Patch Improves Scarless Urethral Regeneration.
- Author
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Wang, Liyang, Wang, Kai, Yang, Ming, Yang, Xi, Li, Danyang, Liu, Meng, Niu, Changmei, Zhao, Weixin, Li, Wenyao, Fu, Qiang, and Zhang, Kaile
- Subjects
GRAPHENE oxide ,GELATIN ,SODIUM alginate ,STRUCTURAL stability ,URETHRA stricture ,CELL survival ,CELL proliferation - Abstract
The nasty urine microenvironment (UME) is an inherent obstacle that hinders urethral repair due to fibrosis and swelling of the oftentimes adopted hydrogel‐based biomaterials. Here, using reduced graphene oxide (rGO) along with double‐freeze‐drying to strengthen a 3D‐printed patch is reported to realize scarless urethral repair. The sodium alginate/gelatin/reduced graphene oxide (SA/Gel/rGO) biomaterial features tunable stiffness, degradation profile, and anti‐fibrosis performance. Interestingly, the 3D‐printed alginate‐containing composite scaffold is able to respond to Ca2+ present in the urine, leading to enhanced structural stability and strength as well as inhibiting swelling. The investigations present that the swelling behaviors, mechanical properties, and anti‐fibrosis efficacy of the SA/Gel/rGO patch can be modulated by varying the concentration of rGO. In particular, rGO in optimal concentration shows excellent cell viability, migration, and proliferation. In‐depth mechanistic studies reveal that the activation of cell proliferation and angiogenesis‐related proteins, along with inhibition of fibrosis‐related gene expressions, play an important role in scarless repair by the 3D‐printed SA/Gel/rGO patch via promoting urothelium growth, accelerating angiogenesis, and minimizing fibrosis in vivo. The proposed strategy has the potential of resolving the dilemma of necessary biomaterial stiffness and unwanted fibrosis in urethral repair. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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- View/download PDF
35. Engineering Heterogeneous Tumor Models for Biomedical Applications.
- Author
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Wu, Zhuhao, Huang, Danqing, Wang, Jinglin, Zhao, Yuanjin, Sun, Weijian, and Shen, Xian
- Subjects
TISSUE engineering ,TUMOR microenvironment ,TUMORS ,SCIENTIFIC models ,CELLULAR signal transduction ,CELL proliferation - Abstract
Tumor tissue engineering holds great promise for replicating the physiological and behavioral characteristics of tumors in vitro. Advances in this field have led to new opportunities for studying the tumor microenvironment and exploring potential anti‐cancer therapeutics. However, the main obstacle to the widespread adoption of tumor models is the poor understanding and insufficient reconstruction of tumor heterogeneity. In this review, the current progress of engineering heterogeneous tumor models is discussed. First, the major components of tumor heterogeneity are summarized, which encompasses various signaling pathways, cell proliferations, and spatial configurations. Then, contemporary approaches are elucidated in tumor engineering that are guided by fundamental principles of tumor biology, and the potential of a bottom‐up approach in tumor engineering is highlighted. Additionally, the characterization approaches and biomedical applications of tumor models are discussed, emphasizing the significant role of engineered tumor models in scientific research and clinical trials. Lastly, the challenges of heterogeneous tumor models in promoting oncology research and tumor therapy are described and key directions for future research are provided. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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- View/download PDF
36. Down‐regulation of miR‐21‐5p by pirfenidone to inhibit fibroblast proliferation in the treatment of acquired tracheal stenosis.
- Author
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Li, Wentao, Huang, Pingping, Wei, Jinmei, Tan, Sen, Liu, Guangnan, Yang, Qiu, and Wang, Guangfa
- Subjects
TRACHEAL stenosis ,FIBROBLASTS ,GENE expression ,POLYMERASE chain reaction ,MESSENGER RNA ,FIBROSIS - Abstract
Objective: Treatment options for acquired tracheal stenosis (ATS) are limited due to a series of pathophysiological changes including inflammation and cell proliferation. Micro ribonucleic acid‐21‐5p (miR‐21‐5p) may promote the excessive proliferation of fibroblasts. However, various types of fibrosis can be prevented with pirfenidone (PFD). Currently, the effect of PFD on miR‐21‐5p and its biological function has not been clarified. In this study, PFD was evaluated as a potential treatment for ATS by inducing fibroblast proliferation in lipopolysaccharide (LPS)‐induced fibroblasts by targeting miR‐21‐5p. Methods: For 48 h, 1 g/ml LPS was used to generate fibroblasts in vitro, followed by the separation of cells into four groups: control, PFD, mimic, and mimic + PFD. The Cell Counting Kit‐8 (CCK‐8) technique was adopted to measure the proliferation of fibroblasts. Real‐time quantitative polymerase chain reaction (RT‐qPCR) and Western blot (WB) were used to measure the relative expressions of tumor necrosis factor‐α (TNF‐α), transforming growth factor‐β1 (TGF‐β1), drosophila mothers against decapentaplegic 7 (Smad7) and collagen type I alpha 1(COL1A1) messenger RNA (mRNA) and proteins, respectively. Results: (1) At 0, 24, 48, and 72 h, fibroblast growth was assessed using the CCK‐8 method. Compared with the control group, the mimic group showed the highest fibroblast viability, and the PFD group showed the lowest fibroblast viability. However, fibroblast viability increased in the mimic + PFD group but decreased in the mimic one. (2) RT‐qPCR and WB showed that the mimic group exhibited a significant up‐regulation in the relative expressions of TNF‐α, TGF‐β1, and COL1A1 mRNA and proteins but a down‐regulation in the relative expression of Smad7 mRNA and protein compared with the control one. In the PFD group, the results were the opposite. Nevertheless, the relative expressions of TNF‐α, TGF‐β1, and COL1A1 mRNA and proteins were increased, whereas that of Smad7 mRNA was decreased in the mimic + PFD group. The change was less in the mimic group. Conclusion: PFD may have a preventive and curative effect on ATS by inhibiting fibroblast proliferation and the fibrotic process and possibly through down‐regulating miR‐21‐5p and up‐regulating Smad7 and its mediated fibrotic and inflammatory responses. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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37. Fabrication of Cu/ZnO‐loaded chitosan hydrogel for an effective wound dressing material to advanced wound care and healing efficiency after caesarean section surgery.
- Author
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Wang, Qiaoying, Li, Qingqing, Zhu, Lingping, Lin, Chenxiao, Chen, Qiaoling, and Chen, Hong
- Subjects
WOUND healing ,POLYSACCHARIDES ,CELL migration ,HYDROCOLLOID surgical dressings ,ZINC oxide ,MICROBIOLOGICAL assay ,POSTOPERATIVE care ,ANTI-infective agents ,GRAM-positive bacterial infections ,SURGICAL site ,CELL proliferation ,CESAREAN section ,GRAM-negative bacterial diseases ,NANOPARTICLES - Abstract
Wound infections and delayed complications after caesarean section surgical procedure to mothers would have a prevalence of discomfort, stress and dissatisfaction in the postpartum period. In this report, one‐pot synthesis is used for the preparation of chitosan (CS)‐based copper nanoparticles (nCu), which was used for the preparation of zinc oxide (ZnO) hydrogel as wound dressing materials after surgery. The antibacterial activity of (CS‐nCu/ZnO) developed hydrogels was studied zone of inhibition, against gram‐positive and gram‐negative bacteria. The antibacterial activity of the CS‐nCu/ZnO hydrogel demonstrated that nanoformulated hydrogel materials have provided excellent bactericidal action against clinically approved bacterial pathogens. The biocompatibility and in vitro wound healing potential of the developed wound closure materials were studied by MTT assay and wound scratch assay methods, respectively. The MTT assay and cell migration assay results demonstrated that CS‐nCu/ZnO hydrogel material induces cell compatibility and effective cell proliferation ability. These findings suggest that the CS‐nCu/ZnO hydrogel outperforms CS‐ZnO in terms of wound healing and could be used as a wound closure material in caesarean section wound treatment. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
38. BDH1‐mediated LRRC31 regulation dependent on histone lysine β‐hydroxybutyrylation to promote lung adenocarcinoma progression.
- Author
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Huang, Jingjing, Liang, Lu, Jiang, Shiyao, Liu, Yueying, He, Hua, Sun, Xiaoyan, Li, Yi, Xie, Li, Tao, Yongguang, Cong, Li, and Jiang, Yiqun
- Subjects
LEUCINE ,LYSINE ,BUTYRATES ,ADENOCARCINOMA ,LUNGS ,LUNG cancer ,CELL proliferation - Abstract
Lung adenocarcinoma (LUAD) is the most common form of lung cancer, with a consistently low 5‐year survival rate. Therefore, we aim to identify key genes involved in LUAD progression to pave the way for targeted therapies in the future. BDH1 plays a critical role in the conversion between acetoacetate and β‐hydroxybutyrate. The presence of β‐hydroxybutyrate is essential for initiating lysine β‐hydroxybutyrylation (Kbhb) modifications. Histone Kbhb at the H3K9 site is attributed to transcriptional activation. We unveiled that β‐hydroxybutyrate dehydrogenase 1 (BDH1) is not only conspicuously overexpressed in LUAD, but it also modulates the overall intracellular Kbhb modification levels. The RNA sequencing analysis revealed leucine‐rich repeat‐containing protein 31 (LRRC31) as a downstream target gene regulated by BDH1. Ecologically expressed BDH1 hinders the accumulation of H3K9bhb in the transcription start site of LRRC31, consequently repressing the transcriptional expression of LRRC31. Furthermore, we identified potential BDH1 inhibitors, namely pimozide and crizotinib, which exhibit a synergistic inhibitory effect on the proliferation of LUAD cells exhibiting high expression of BDH1. In summary, this study elucidates the molecular mechanism by which BDH1 mediates LUAD progression through the H3K9bhb/LRRC31 axis and proposes a therapeutic strategy targeting BDH1‐high‐expressing LUAD, providing a fresh perspective for LUAD treatment. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
39. Fabrication of Zein‐Based Fibrous Scaffolds for Biomedical Applications—A Review.
- Author
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Rahman, Mustafijur, Dip, Tanvir Mahady, Haase, Tina, Truong, Yen Bach, Le, Tu C., and Houshyar, Shadi
- Subjects
TISSUE scaffolds ,CELL adhesion ,CELL proliferation ,MEDICAL research ,ELECTROSPINNING ,BIOCOMPATIBILITY - Abstract
Zein, which accounts for around 80% of the total protein composition in corn, is a biocompatible and biodegradable substance derived from renewable sources. Although insoluble in water, its amphiphilic characteristics are utilized to generate nanoparticles, nanofibers, microparticles, and even films. Numerous recent studies have demonstrated the potential of zein as a prospective biomaterial to develop fibrous scaffolds for biomedical functions owing to its biocompatibility, fibrous formation, and encapsulating qualities. Fabrication of zein‐based fibrous scaffolds for biomedical applications is achieved by a wide variety of techniques, including electrospinning, wet spinning, freeze drying, and additive manufacturing. This article overviews current advancements in manufacturing techniques for zein‐based fibrous scaffolds. In addition, it summarizes the most recent biomedical applications and research activities utilizing zein‐based fibrous scaffolds. Overall, zein is proposed as a potential biomaterial for the production of fibrous scaffolds that stimulate cell adhesion and proliferation in a number of exciting biomedical applications due to its biodegradability, biocompatibility, and other unique features related to its structure. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
40. ETV5 regulates proliferation and cell cycle genes in the INS‐1 (832/13) cell line independently of the concentration of secreted insulin.
- Author
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Díaz‐López, Yael E., Pérez‐Figueroa, Gloria Erandi, Cázares‐Domínguez, Vicenta, Frigolet, María E., and Gutiérrez‐Aguilar, Ruth
- Subjects
CELL cycle ,CELL proliferation ,INSULIN ,CELL lines ,CELL size ,CELL cycle regulation - Abstract
The transcription factor E‐twenty‐six variant 5 (ETV5) regulates acute insulin secretion. Adequate insulin secretion is dependent on pancreatic β‐cell size and cell proliferation, but the effects of ETV5 on proliferation, cell number, and viability, as well as its relationship with insulin secretion, have not been established yet. Here, we partially silenced ETV5 in the INS‐1 (832/13) cell line by siRNA transfection and then measured secreted insulin concentration at different time points, observing similar levels to control cells. After 72 h of ETV5 silencing, we observed decreased cell number and proliferation, without any change in viability or apoptosis. Thus, partial silencing of ETV5 modulates cell proliferation in INS‐1 (832/13) independently of secreted insulin levels via upregulation of E2F1 and of inhibitors of the cyclin/CDKs complexes (p21Cdkn1a, p27Cdkn1b, and p57Cdkn1c) and downregulation of cell cycle activators (PAK3 and FOS). [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
41. Biogenic Imaging Contrast Agents.
- Author
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Dan, Qing, Jiang, Xinpeng, Wang, Run, Dai, Zhifei, and Sun, Desheng
- Subjects
CONTRAST media ,REPORTER genes ,MAGNETIC resonance imaging ,ULTRASONIC imaging ,FLUORESCENT proteins ,CELL proliferation - Abstract
Imaging contrast agents are widely investigated in preclinical and clinical studies, among which biogenic imaging contrast agents (BICAs) are developing rapidly and playing an increasingly important role in biomedical research ranging from subcellular level to individual level. The unique properties of BICAs, including expression by cells as reporters and specific genetic modification, facilitate various in vitro and in vivo studies, such as quantification of gene expression, observation of protein interactions, visualization of cellular proliferation, monitoring of metabolism, and detection of dysfunctions. Furthermore, in human body, BICAs are remarkably helpful for disease diagnosis when the dysregulation of these agents occurs and can be detected through imaging techniques. There are various BICAs matched with a set of imaging techniques, including fluorescent proteins for fluorescence imaging, gas vesicles for ultrasound imaging, and ferritin for magnetic resonance imaging. In addition, bimodal and multimodal imaging can be realized through combining the functions of different BICAs, which helps overcome the limitations of monomodal imaging. In this review, the focus is on the properties, mechanisms, applications, and future directions of BICAs. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
42. Cell proliferation in in vivo-like three-dimensional cell culture is regulated by sequestration of ERK1/2 to lipid rafts.
- Author
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Skrobanska, R., Evangelatov, A., Stefanova, N., Topouzova‐Hristova, T., Momchilova, A., and Pankov, R.
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CELL proliferation ,CELL culture ,FIBROSIS ,FIBROBLASTS ,EXTRACELLULAR matrix ,IMMUNOHISTOCHEMISTRY ,IMMUNOFLUORESCENCE - Abstract
Objectives Regulatory mechanisms of cell proliferation have been extensively studied as they represent major challenges when dealing with pathologies such as fibrosis, tumourigenesis or tissue regeneration. Numerous in vitro studies still exploit conventional, two-dimensional cell cultures where cells are forced to adhere to unnaturally stiff and flat surfaces of culture dishes. In the living organism, however, each cell is in contact with components of the extracellular matrix and/or neighbouring cells, thus creating a complex three-dimensional (3D) tissue structure. The current paper describes a native 3D culture of cells, based on the GD25β1 fibroblast cell line, and its use for investigating cell proliferation in in vivo-like conditions. Materials and methods Four-day post-confluent culture of GD25β1 fibroblasts resulted in formation of a 3D system of cells embedded in naturally synthesized extracellular matrix. Morphological characterization of the culture was performed by histochemistry, immunohistochemistry and immunofluorescence. Viability/proliferation was assayed by MTT testing, FACS analysis and Western blotting for determination of expression levels and activation status of the relevant signalling molecules. Results GD25b1 fibroblasts, grown as 3D culture, gave rise to tissue-like structures characterized by low level of apoptosis, low senescence and development of 3D matrix adhesions, typical of living tissues. Transition to three-dimensionality led to a switch from exponential to linear culture growth, accompanied by accumulation of activated ERK1/2 into caveolin-containing raft domains. Disruption of raft domains as well as reverse transition from 3D back to monolayer culture led to release of phosphorylated ERK1/2 from rafts, activation of cyclin D1 expression and increase in proliferation levels. Conclusions These results imply that under in vivo-like conditions, cells might achieve reduction of their proliferation level by sequestering activated ERK1/2 to lipid rafts. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
43. New treatments for autosomal dominant polycystic kidney disease.
- Author
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Chang, Ming-Yang and Ong, Albert C. M.
- Subjects
POLYCYSTIC kidney disease ,GENETIC mutation ,CELL proliferation ,EXTRACELLULAR matrix ,FIBROSIS - Abstract
Autosomal dominant polycystic kidney disease ( ADPKD) is the most common inherited kidney disease and results from mutations in PKD1 or PKD2. Cyst initiation and expansion arise from a combination of abnormal cell proliferation, fluid secretion and extracellular matrix defects and results in kidney enlargement and interstitial fibrosis. Since its first description over 200 years ago, ADPKD has been considered an untreatable condition and its management is limited to blood pressure reduction and symptomatic treatment of disease complications. Results of the recently reported TEMPO 3/4 trial thus represent a paradigm shift in demonstrating for the first time that cystic disease and loss of renal function can be slowed in humans. In this paper, we review the major therapeutic strategies currently being explored in ADPKD including a range of novel approaches in preclinical models. It is anticipated that the clinical management of ADPKD will undergo a revolution in the next decade with the translation of new treatments into routine clinical use. [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF
44. Radiation sensitivity increases with proliferation-associated telomere dysfunction in nontransformed human epithelial cells.
- Author
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Soler D, Pampalona J, Tusell L, and Genescà A
- Subjects
- Cell Line, Cellular Senescence, DNA Damage, Epithelial Cells cytology, Epithelial Cells metabolism, Genome, Human radiation effects, Humans, Cell Proliferation radiation effects, Epithelial Cells radiation effects, Radiation Tolerance, Telomere radiation effects
- Abstract
Epidemiological studies have demonstrated age differences among human adults in susceptibility to radiation, with cancer cases attributable to radiation being more frequent for older individuals at time of exposure. In addition to the notion that susceptibility increases because of progressive decline in DNA monitoring and immunosurveillance, telomere function is now emerging as a new and important factor in modulating cellular and organism sensitivity to ionizing radiation. The link between telomeres and radiosensitivity is well-documented in humans, but the causal events remain elusive. In this paper, it is shown that irradiated human epithelial cells with short dysfunctional telomeres derived from normal mammary gland display elevated DNA damage. An approach identifying the specific chromosomes with critically shortened telomeres in each donor has allowed us to conclude that short dysfunctional telomeres in human epithelial cells join radiation-induced DNA broken ends, thus interfering with their efficient repair. These findings argue against telomeres participating as sensors or transducers of DNA damage, as previously suggested. Rather, our current findings give support to the idea that dysfunctional telomeres, by acting as an additional joining option, reduce the repair fidelity of DNA broken-ends induced by radiation throughout the genome. In the mammary gland, age-dependent telomere attrition due to epithelial turnover, together with the accretion of checkpoint deficiencies, might render the accumulation of short dysfunctional telomeres. This implies that the risks associated with mammography screening could be higher than previously assumed. Our results have the possibility of imprinting a temporal dimension onto radiation sensitivity, namely, that shortened telomeres in aged cells may more easily compromise normal tissue function in the elderly.
- Published
- 2009
- Full Text
- View/download PDF
45. Mechanisms regulating epidermal stem cells.
- Author
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Beck, Benjamin and Blanpain, Cédric
- Subjects
STEM cells ,EPIDERMIS ,HAIR follicles ,SEBACEOUS glands ,CELL proliferation ,CELL differentiation ,CHROMATIN - Abstract
The skin epidermis contains different appendages such as the hair follicle and the sebaceous glands. Recent studies demonstrated that several types of stem cells (SCs) exist in different niches within the epidermis and maintain discrete epidermal compartments, but the exact contribution of each SC populations under physiological conditions is still unclear. In addition, the precise mechanisms controlling the balance between proliferation and differentiation of epidermal SC still remain elusive. Recent studies provide new insights into these important questions by showing the contribution of hair follicle SC to the sebaceous lineage and the importance of chromatin modifications and micro-RNAs (miRs) in regulating epidermal SCs renewal and differentiation. In this review, we will discuss the importance of these papers to our understanding of the mechanisms that control epidermal SC functions. [ABSTRACT FROM AUTHOR]
- Published
- 2012
- Full Text
- View/download PDF
46. Induction of contact-dependent CD8+ regulatory T cells through stimulation with staphylococcal and streptococcal superantigens.
- Author
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Taylor, Amanda L., Cross, Elizabeth L. A., and Llewelyn, Martin J.
- Subjects
STAPHYLOCOCCAL disease treatment ,CYTOTOXIC T cells ,GENETIC regulation ,SUPERANTIGENS ,TOXIC shock syndrome ,CELL proliferation ,BIOMARKERS - Abstract
Summary The bacterial superantigen exotoxins of Staphylococcus aureus and Streptococcus pyogenes are potent stimulators of polyclonal T-cell proliferation. They are the causes of toxic shock syndrome but also induce CD25
+ FOXP3+ regulatory cells in the CD4 compartment. Several studies have recently described different forms of antigen-induced regulatory CD8+ T cells in the context of inflammatory diseases and chronic viral infections. In this paper we show that bacterial superantigens are potent inducers of human regulatory CD8+ T cells. We used four prototypic superantigens of S. aureus (toxic shock syndrome toxin-1 and staphylococcal enterotoxin A) and Str. pyogenes (streptococcal pyrogenic exotoxins A and K/L). At concentrations below 1 ng/ml each toxin triggers concentration-dependent T-cell receptor Vβ-specific expression of CD25 and FOXP3 on CD8+ T cells. This effect is independent of CD4+ T-cell help but requires antigen-presenting cells for maximum effect. The cells also express the activation/regulatory markers cytotoxic T-lymphocyte antigen-4 and glucocorticoid-induced tumour necrosis factor receptor-related protein and skin homing adhesins CD103 and cutaneous lymphocyte-associated antigen. Superantigen-induced CD25+ FOXP3+ CD8+ T cells were as potent as freshly prepared naturally occurring CD4+ regulatory T cells in suppressing proliferation of CD4+ CD25− T cells in response to anti-CD3 stimulation. Although superantigen-induced CD8+ CD25+ FOXP3+ express interleukin-10 and interferon-γ their suppressive function is cell contact dependent. Our findings indicate that regulatory CD8+ T cells may be a feature of acute bacterial infections contributing to immune evasion by the microbe and disease pathogenesis. The presence and magnitude of regulatory CD8+ T-cell responses may represent a novel biomarker in such infections. Superantigen-induced regulatory CD8+ T cells also have therapeutic potential. [ABSTRACT FROM AUTHOR]- Published
- 2012
- Full Text
- View/download PDF
47. Activation of p38 mitogen-activated protein kinase is critical step for acquisition of effector function in cytokine-activated T cells, but acts as a negative regulator in T cells activated through the T-cell receptor.
- Author
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Li, Ching, Beavis, Paul, Palfreeman, Andrew C., Amjadi, Parisa, Kennedy, Alan, and Brennan, Fionula M.
- Subjects
MITOGEN-activated protein kinases ,CYTOKINES ,T cell receptors ,CD4 antigen ,TUMOR necrosis factors ,CELL proliferation ,CELLULAR signal transduction - Abstract
Peripheral blood CD4 CD45RO T cells activated in vitro are able to induce expression of tumour necrosis factor-α (TNF-α) in monocytes via a contact-dependent mechanism. Activation is achieved either with interleukin-2 (IL-2)/IL-6/TNF-α over an 8-day period or cross-linking CD3 using anti-CD3 antibody for 48 hr. In this paper, we show that the p38 mitogen-activated protein kinase (MAPK) signalling pathway played different roles in the generation of effector function in these two types of activated T cells. In anti-CD3 activated T cells, p38 MAPK is a negative regulator for anti-CD3 induced cell proliferation and has no significant effect on the acquisition of either the effector function (induction of monocyte-derived TNF-α) or production of T-cell cytokines. In contrast, the p38 MAPK signalling pathway is required for the acquisition of cytokine-induced effector function and promotes cell proliferation and cytokine production. [ABSTRACT FROM AUTHOR]
- Published
- 2011
- Full Text
- View/download PDF
48. Nitric oxide is required for, and promotes auxin-mediated activation of, cell division and embryogenic cell formation but does not influence cell cycle progression in alfalfa cell cultures.
- Author
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Ötvös, Krisztina, Pasternak, Taras P., Miskolczi, Pál, Domoki, Mónika, Dorjgotov, Dulguun, Szűcs, Attila, Bottka, Sándor, Dudits, Dénes, and Fehér, Attila
- Subjects
NITRIC oxide ,PLANT cells & tissues ,CELL proliferation ,CELL cycle ,BIOLOGICAL rhythms ,CELL cycle regulation ,PLANT hormones - Abstract
It is now well established that nitric oxide (NO) serves as a signaling molecule in plant cells. In this paper experimental data are presented which indicate that NO can stimulate the activation of cell division and embryogenic cell formation in leaf protoplast-derived cells of alfalfa in the presence of auxin. It was found that various NO-releasing compounds promoted auxin-dependent division (as shown by incorporation of bromodeoxyuridine) of leaf protoplast-derived alfalfa cells. In contrast, application of NO scavenger or NO synthesis inhibitor inhibited the same process. Both the promotion and the inhibition of cell cycle activation correlated with the amount and activity of the cognate alfalfa p34
cdc2 protein Medsa;CDKA;1,2. The effect of l-NG-monomethyl- l-arginine ( l-NMMA) was transient, and protoplast-derived cells spending more than 3 days in culture become insensitive to the inhibitor as far as cell cycle progression was concerned. l-NMMA had no effect on the cell cycle parameters of cycling suspension-cultured cells, but had a moderate transient inhibitory effect on cells re-entering the cell cycle following phosphate starvation. Cycling cultured cells, however, could respond to NO, as indicated by the sodium nitroprusside (SNP)- and 2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (PTIO)-dependent accumulation of the ferritin protein. Based on these observations, it is hypothesized that l-NMMA-sensitive generation of NO is involved in the activation, but not the progression of the plant cell division cycle. In addition, SNP promoted and l-NMMA delayed the exogenous auxin [2,4-dichlorophenoxyacetic acid (2,4-D)] concentration-dependent formation of embryogenic cell clusters expressing the MsSERK1 gene; this further supports a link between auxin- and NO-dependent signaling pathways in plant cells. [ABSTRACT FROM AUTHOR]- Published
- 2005
- Full Text
- View/download PDF
49. Training of yeast cell dynamics.
- Author
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Reijenga, Karin A., Bakker, Barbara M., van der Weijden, Coen C., and Westerhoff, Hans V.
- Subjects
YEAST ,CELL proliferation ,LEAVENING agents ,CELLS ,MICROORGANISMS ,GENETICS - Abstract
In both industrial fermenters and in their natural habitats, microorganisms often experience an inhomogeneous and fluctuating environment.In this paper we mimicked one aspect of this nonideal behaviour by imposing a low and oscillating extracellular glucose concentration on nonoscillating suspensions of yeast cells. The extracellular dynamics changed the intracellular dynamics– which was monitored through NADH fluorescence– from steady to equally dynamic; the latter followed the extracellular dynamics at the frequency of glucose pulsing. Interestingly, the amplitude of the oscillation of the NADH fluorescence increased with time. This increase in amplitude was sensitive to inhibition of protein synthesis, and was due to a change in the cells rather than in the medium; the cell population was‘trained’ to respond to the extracellular dynamics. To examine the mechanism behind this‘training’, we subjected the cells to a low and constant extracellular glucose concentration. Seventy-five minutes of adaptation to a low and constant glucose concentration induced the same increase of the amplitude of the forced NADH oscillations as did the train of glucose pulses. Furthermore, 75 min of adaptation to a low (oscillating or continuous) glucose concentration decreased theK
M of the glucose transporter from 26 mmto 3.5 mm. When subsequently the apparentKM was increased by addition of maltose, the amplitude of the forced oscillations dropped to its original value. This demonstrated that the increased affinity of glucose transport was essential for the training of the cells' dynamics. [ABSTRACT FROM AUTHOR]- Published
- 2005
- Full Text
- View/download PDF
50. ABSTRACTS Abstracts of the 26th Meeting of the European Study Group for Cell Proliferation (ESGCP).
- Subjects
CELL proliferation ,CONFERENCES & conventions ,STEM cell research ,GRANULOCYTE-colony stimulating factor ,BONE marrow ,CELL cycle - Abstract
Presents abstracts of paper submitted to the 26th Meeting of the European Study Group for Cell Proliferation. Adult stem cell research with expectation of reversing organ damage caused by old age and disease; Morphology of the bone marrow during stimulation with G-CSF in mice; Advances in cell cycle control.
- Published
- 2004
- Full Text
- View/download PDF
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