PI3K/AKT Pathway Promotes Keloid Fibroblasts Proliferation by Enhancing Glycolysis Under Hypoxia

Abstract Background Keloids are disfiguring fibro-proliferative disorders characterized by glucose metabolism reprogramming, namely elevated glycolysis and compromised oxidative phosphorylation. Our previous study demonstrated altered glucose metabolism and enhanced phosphorylation of the PI3K/AKT pathway in keloid fibroblasts (KFb) under hypoxic conditions. However, whether the PI3K/AKT pathway influences KFb cell function by regulating glucose metabolism under hypoxic conditions remains unclear. Results Our findings revealed that when the PI3K/AKT pathway was inactivated with LY294002 under hypoxia, the protein expression of glycolytic enzymes GLUT1, HK2, PFKFB3, PGK1, ENO1, PKM2, and LDHA decreased under hypoxia, while the amount of mitochondria and mitochondrial membrane potential (MMP) increased, and mitochondrial ultrastructure in KFb remained unchanged. The key parameters of extracellular acidification rate (ECAR) markedly diminished, and those of oxygen consumption rate (OCR) significantly increased after inhibition of the PI3K/AKT pathway. When the PI3K/AKT pathway was suppressed, the levels of ROS and mitochondrial ROS were significantly increased. Meanwhile, cell proliferation, migration, and invasion were inhibited, and apoptosis was increased when the PI3K/AKT pathway was blocked. Additionally, cell proliferation was compromised when KFb were treated with both SC79 (an activator of the PI3K/AKT pathway) and 2-DG (an inhibitor of glycolysis), compared to the SC79 group. Moreover, a positive feedback mechanism was demonstrated in the PI3K/AKT pathway and HIF-1α. Conclusions Our data collectively demonstrated that the PI3K/AKT pathway promotes proliferation and inhibits apoptosis in KFb under hypoxia by regulating glycolysis, indicating that the PI3K/AKT signaling pathway could be a therapeutic target for keloids.

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Altered glucose metabolism and cell function in keloid fibroblasts under hypoxia

Redox Biology ◽

10.1016/j.redox.2020.101815 ◽

2021 ◽

Vol 38 ◽

pp. 101815

Author(s):

Qifei Wang ◽

Pu Wang ◽

Zelian Qin ◽

Xin Yang ◽

Bailin Pan ◽

...

Keyword(s):

Glucose Metabolism ◽

Cell Function ◽

Altered Glucose ◽

Keloid Fibroblasts

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MiR-489-3p inhibits cell proliferation, migration, and invasion, and induces apoptosis, by targeting the BDNF-mediated PI3K/AKT pathway in glioblastoma

Open Life Sciences ◽

10.1515/biol-2020-0024 ◽

2020 ◽

Vol 15 (1) ◽

pp. 274-283

Author(s):

Bo Zheng ◽

Tao Chen

Keyword(s):

Cell Proliferation ◽

Luciferase Reporter ◽

Akt Pathway ◽

Migration And Invasion ◽

Bdnf Mrna ◽

Protein Levels ◽

Rna Immunoprecipitation ◽

Underlying Mechanisms ◽

Induced Apoptosis ◽

Protein Cell

AbstractAmong astrocyte tumors, glioblastoma (GBM) is the most malignant glioma, highly aggressive and invasive, with extremely poor prognosis. Previous research has reported that microRNAs (miRNAs) participate in the progression of many cancers. Thus, this study aimed to explore the role and the underlying mechanisms of microRNA (miR)-489-3p in GBM progression. The expression of miR-489-3p and brain-derived neurotrophic factor (BDNF) mRNA was measured by quantitative real-time polymerase chain reaction. Western blot analysis was used to detect BDNF protein and the PI3K/AKT pathway-related protein. Cell proliferation, apoptosis, migration, and invasion were analyzed using CKK-8 assay, flow cytometry, and transwell assay, respectively. The interaction between BDNF and miR-489-3p was explored by luciferase reporter assay and RNA immunoprecipitation (RIP) assay. MiR-489-3p was down-regulated and BDNF was up-regulated in GBM tissues and cells. MiR-489-3p re-expression or BDNF knockdown inhibited GBM cell proliferation, migration, and invasion, and promoted apoptosis. BDNF was a target of miR-489-3p, and BDNF up-regulation reversed the effects of miR-489-3p on GBM cells. The protein levels of p-AKT and p-PI3K were notably reduced in GBM cells by overexpression of miR-489-3p, but were rescued following BDNF up-regulation. Therefore, miR-489-3p inhibited proliferation, migration, and invasion, and induced apoptosis, by targeting the BDNF-mediated PI3K/AKT pathway in GBM, providing new strategies for clinical treatment of GBM.

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Biomarker potential of lncRNA GNAS-AS1 in osteosarcoma prognosis and effect on cellular function

Journal of Orthopaedic Surgery and Research ◽

10.1186/s13018-021-02611-2 ◽

2021 ◽

Vol 16 (1) ◽

Author(s):

Zhanhu Mi ◽

Yanyun Dong ◽

Zhibiao Wang ◽

Peng Ye

Keyword(s):

Cell Proliferation ◽

Cell Function ◽

Cox Regression ◽

Bone Cancer ◽

Prognostic Indicator ◽

Migration And Invasion ◽

Rank Test ◽

Chi Square ◽

Invasion And Migration ◽

Novel Therapeutic Strategies

Abstract Background Osteosarcoma (OS) is a type of bone cancer that occurs in children and adolescents at a rate of 5%. The purpose of this study is to explore the lncRNA GNAS-AS1 expression profile, prognosis significance in OS, and biological effect on OS cell function. Methods One hundred eight pairs of tissues were collected, and OS cell lines were purchased. lncRNA GNAS-AS1 expression in these tissues and cells were analyzed by qRT-PCR. Clinical data were analyzed using chi-square tests, Kaplan-Meier curves (log-rank test), and Cox regression. CCK-8 and transwell assay were conducted to analyze the effect of lncRNA GNAS-AS1 on cell proliferation, invasion, and migration. The downstream miRNA was presumed. Results The expression of lncRNA GNAS-AS1 was significantly increased in OS cells and tissues, and related to Enneking staging and distant metastasis. Patients with high lncRNA GNAS-AS1 expression represented shorter overall survival and was an independent prognostic predictor of OS. LncRNA GNAS-AS1 knockdown inhibited cell proliferation, migration, and invasion by regulated miR-490-3p partly at least. Conclusions LncRNA GNAS-AS1 can be used as a prognostic indicator and its inhibition suppress the development of OS, suggesting its value as novel therapeutic strategies in OS.

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FOXD3 inhibits cell proliferation, migration, and invasion in nasopharyngeal carcinoma through regulation of the PI3K–Akt pathway

Biochemistry and Cell Biology ◽

10.1139/bcb-2020-0011 ◽

2020 ◽

Vol 98 (6) ◽

pp. 653-660 ◽

Cited By ~ 1

Author(s):

Xiaoxing Xie ◽

Gaoyun Xiong ◽

Wenjun Chen ◽

Hongdan Fu ◽

Mingqian Li ◽

...

Keyword(s):

Cell Proliferation ◽

Nasopharyngeal Carcinoma ◽

Cell Apoptosis ◽

Inhibitory Effect ◽

Akt Pathway ◽

Migration And Invasion ◽

Inhibitory Effects ◽

Protein Levels ◽

Flow Cytometric ◽

Phosphoinositide 3 Kinase

FOXD3 has been found previously to positively regulate miR-26b, a tumor inhibitor of nasopharyngeal carcinoma (NPC). However, FOXD3’s precise function and associated mechanism of action in NPC have not yet been investigated. In this study, the expression of FOXD3 mRNA and protein was evaluated using RT-qPCR, western blotting, and immunohistochemistry. Protein levels involved in the phosphoinositide 3-kinase – protein kinase B (PI3K–Akt) pathway were assessed by western blot, and cell proliferation was determined by MTT and colony forming assays. Additionally, cell apoptosis was assessed by flow cytometric assay. Finally, the migration and invasion capabilities of the NPC cells were determined using wound healing and Transwell assays. We found that FOXD3 levels were relatively low in NPC tissue and cells, while an increase caused the inhibition of the PI3K–Akt pathway. Functional experiments found that overexpression of FOXD3 suppressed cell proliferation, migration, and invasion and enhanced cell apoptosis in NPC C6661 cells. IGF-1, an activator of the PI3K–Akt pathway, reversed the inhibitory effect of FOXD3. Furthermore, we found upregulation of the PI3K–Akt pathway and upregulation of the inhibitory effects of FOXD3 on C6661 cellular activities. In conclusion, FOXD3 negatively affected the PI3K–Akt pathway to restrain the processes involved in C6661 cell pathology. These findings further exposed the function and downstream axis of FOXD3 in NPC and displayed a promising new target for NPC therapy.

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Lin28 Enhances Glucose Metabolism in Human Placental Mesenchymal Stem Cells during Hypoxia via the PI3K-Akt Pathway

10.21203/rs.3.rs-892582/v1 ◽

2021 ◽

Author(s):

Xi Zhou ◽

Junbo Li ◽

Jin Wang ◽

Huifang Yang ◽

Jingzeng Wang ◽

...

Keyword(s):

Stem Cells ◽

Mesenchymal Stem Cells ◽

Stem Cell ◽

Glucose Metabolism ◽

Ischemia Reperfusion ◽

Stem Cell Differentiation ◽

Akt Signaling ◽

Akt Pathway ◽

Western Blots ◽

Hypoxic Conditions

Abstract Mesenchymal stem cells (MSCs) are widely used to treat and prevent liver ischemia–reperfusion injury (LIRI), which commonly occurs after liver surgery. Lin28 is an RNA-binding protein crucial for early embryonic development, stem cell differentiation/reprogramming, tumorigenesis, and metabolism. However, whether Lin28 can enhance metabolism in human placental MSCs (PMSCs) during hypoxia to improve the protective effect against LIRI remains unclear. First, a Lin28 overexpression construct was introduced into PMSCs; glucose metabolism, the expression of glucose metabolism - and PI3K-AKT pathway-related proteins, and the levels of microRNA Let-7 family members were examined using a glucose metabolism kit, western blots, and real-time quantitative PCR, respectively. Next, treatment with an AKT inhibitor was performed to understand the association of Lin28 with the PI3K-Akt pathway. Subsequently, AML12 cells were co-cultured with PMSCs to construct an in vitro model of PMSC protecting liver cells from hypoxia injury. Finally, C57BL/6J mice were used to establish a partial warm hepatic ischemia–reperfusion model in vivo. Lin28 increased the glycolysis capacity of PMSCs, allowing these cells to produce more energy under hypoxic conditions. Lin28 also activated PI3K-Akt signaling under hypoxic conditions, and AKT inhibition attenuated the effects of Lin28. In addition, Lin28 overexpression was found to protect cells against LIRI-induced liver damage, inflammation, and apoptosis and attenuate hypoxia-induced hepatocyte injury. Inconclusion, Lin28 enhances glucose metabolism under hypoxic conditions in PMSCs, thereby providing protective effects against LIRI via the activation of the PI3K-Akt signaling pathway. Our study first reported the application of gene-modified mesenchymal stem cell-based therapy in LIRI.

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LncRNA NCRNA00173 is down-regulated in pediatric osteosarcoma and suppresses cell metastasis of osteosarcoma cells through regulating PI3k/Akt pathway

10.21203/rs.2.19195/v1 ◽

2019 ◽

Author(s):

Zhongquan Zhao ◽

Jiechao Chen ◽

Dezhi Xia

Keyword(s):

Cell Proliferation ◽

Protein Expression ◽

Tumor Growth ◽

Nude Mice ◽

Akt Pathway ◽

Migration And Invasion ◽

Kaplan Meier ◽

Disability Rate ◽

Cell Metastasis ◽

The Impact

Abstract Background: Osteosarcoma (OS) is a primary malignant tumor with high mortality and disability rate in childhood and adolescent, whereas the influence of LncRNA00173 (NCRNA00173) on pediatric OS progression is not obvious yet. Therefore, this study aimed to investigate the expression of NCRNA00173 in pediatric OS and its effect on OS progression. Methods: In our study, qRT-PCR was adopted to test the NCRNA00173 expression in 40 pairs of pediatric OS tissues and OS cell lines. Kaplan-Meier method and Cox proportional hazard model were performed to analyze the prognosis of pediatric OS patients. The cell proliferation, apoptosis, migration and invasion of U2OS and HOS cells were test by MTT assay, flow cytometry, wound-healing, and transwell assay, respectively. The protein expression levels of PI3K/Akt pathway were measured by western blot. In addition, tumor growth in nude mice was also detected. Results: The expression of NCRNA00173 was down-regulated and relevant with poor prognosis in pediatric OS. Overexpression of NCRNA00713 inhibited cell proliferation, migration and invasion, as well as accelerated cell apoptosis in U2OS and HOS cells. Overexpression of NCRNA00713 suppressed tumor growth in nude mice. The protein expression of p-PI3K and p-Akt were remarkedly decreased in U2OS and HOS cells after transfection with NCRNA00173. In addition, 740 Y-P (PI3K/Akt pathway activator) eliminated the impact of NCRNA00173 in HOS. Conclusions: NCRNA00173 was down-regulated in pediatric OS and suppressed metastasis of OS cells by regulating PI3k/Akt pathway.

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