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1.
Life Sci ; 242: 117190, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31863773

RESUMO

The alteration of PTEN expression may be a vital part of the pathological and physiological mechanisms in infertility-related with endometriosis. However, the potential mechanisms underlying abnormal expression of PTEN and its role in progesterone-resistant endometriosis have not been thoroughly elucidated. In this study, our data showed the PTEN messenger RNA (mRNA) level and protein expression was reduced in progesterone-resistant endometriosis tissue and primary stomal cells. Low levels of PTEN in endometrial stromal cells led to higher cell proliferation and resistance to progesterone. In terms of PTEN suppression in progesterone-resistant endometriosis, the mRNA level of miR-92a was correlated negatively with PTEN level. Transfection of miR-92a mimic reduced PTEN expression and made the stromal cells more resistant to progesterone treatment. Inhibition of miR-92a by its antagomir had the opposite effects. Results of the luciferase reporter assay for the 3'-nontranslated region suggested that miR-92a directly modulated PTEN levels. Moreover, miR-92a inhibition by its antagomir enhanced the therapeutic effect of progesterone, which suppressed stromal cell proliferation, and reduced the formation of ectopic lesions in the mouse model of endometriosis. Hence, this study revealed that miR-92a contributed to the development of progesterone resistant endometriosis by suppression of PTEN expression, and modulation of miR-92a might be a potential medical method of treating endometriosis.


Assuntos
Endometriose/tratamento farmacológico , MicroRNAs/metabolismo , PTEN Fosfo-Hidrolase/metabolismo , Progesterona/uso terapêutico , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/fisiologia , Adulto , Animais , Células Cultivadas , Modelos Animais de Doenças , Resistência a Medicamentos , Endometriose/metabolismo , Feminino , Humanos , Immunoblotting , Camundongos , MicroRNAs/fisiologia , PTEN Fosfo-Hidrolase/fisiologia , Proteínas Proto-Oncogênicas c-akt/fisiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Estromais/metabolismo
2.
Life Sci ; 242: 117184, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31870775

RESUMO

AIMS: Diabetes mellitus leads to impaired osteogenic differentiation and alveolar bone absorption. Periostin (POSTN) is important for bone and tooth maintenance. This study aims to elucidate the expression of POSTN in high glucose and the effects of both high glucose and POSTN on osteogenesis in hPDLSCs, as well as the underlying mechanism. MAIN METHODS: Cells were incubated with glucose under physiological (5.5 mM normal glucose) or diabetic (30 mM high glucose) conditions in the presence or absence of recombinant human POSTN (rPOSTN). Cell migration was assessed by a scratch assay. Reactive oxygen species (ROS) was used to assess HG-induced oxidative damage. Osteogenesis was evaluated by alkaline phosphatase (ALP) activity and ALP staining, Alizarin Red staining (ARS), as well osteogenic related genes and proteins. KEY FINDINGS: POSTN expression was inhibited during a long-term culture with HG. HG diminished the migration and osteogenesis of hPDLSCs as indicated by decreases in ALP activity and ALP staining, ARS and expression of COL I, RUNX2, OSX, OPN and OCN, but an increase in reactive oxygen species overproduction. All of which were reversed by addition of rPOSTN. POSTN knockdown suppressed migration and osteogenesis of hPDLSCs. Moreover, HG inhibited activation of AKT, which was rescued by addition of POSTN. AKT inhibitor significantly reduced POSTN-mediated osteogenic differentiation. SIGNIFICANCE: rPOSTN could be a therapeutic regime for defective periodontal and peri-implant bone regeneration in diabetes mellitus.


Assuntos
Moléculas de Adesão Celular/metabolismo , Osteogênese , Ligamento Periodontal/crescimento & desenvolvimento , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Adolescente , Western Blotting , Criança , Glucose/farmacologia , Humanos , Ligamento Periodontal/metabolismo , Proteínas Proto-Oncogênicas c-akt/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Células-Tronco/metabolismo , Adulto Jovem
3.
Cancer Sci ; 110(12): 3695-3707, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31571328

RESUMO

Polycomb repressive complex 2 (PRC2) components, EZH2 and its homolog EZH1, and PI3K/Akt signaling pathway are focal points as therapeutic targets for multiple myeloma. However, the exact crosstalk between their downstream targets remains unclear. We herein elucidated some epigenetic interactions following Akt inhibition and demonstrated the efficacy of the combined inhibition of Akt and PRC2. We found that TAS-117, a potent and selective Akt inhibitor, downregulated EZH2 expression at the mRNA and protein levels via interference with the Rb-E2F pathway, while EZH1 was compensatively upregulated to maintain H3K27me3 modifications. Consistent with these results, the dual EZH2/EZH1 inhibitor, UNC1999, but not the selective EZH2 inhibitor, GSK126, synergistically enhanced TAS-117-induced cytotoxicity and provoked myeloma cell apoptosis. RNA-seq analysis revealed the activation of the FOXO signaling pathway after TAS-117 treatment. FOXO3/4 mRNA and their downstream targets were upregulated with the enhanced nuclear localization of FOXO3 protein after TAS-117 treatment. ChIP assays confirmed the direct binding of FOXO3 to EZH1 promoter, which was enhanced by TAS-117 treatment. Moreover, FOXO3 knockdown repressed EZH1 expression. Collectively, the present results reveal some molecular interactions between Akt signaling and epigenetic modulators, which emphasize the benefits of targeting PRC2 full activity and the Akt pathway as a therapeutic option for multiple myeloma.


Assuntos
Compostos Heterocíclicos com 3 Anéis/uso terapêutico , Mieloma Múltiplo/tratamento farmacológico , Complexo Repressor Polycomb 2/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Sinergismo Farmacológico , Proteína Potenciadora do Homólogo 2 de Zeste/antagonistas & inibidores , Proteína Potenciadora do Homólogo 2 de Zeste/fisiologia , Proteína Forkhead Box O3/fisiologia , Humanos , Mieloma Múltiplo/patologia , Complexo Repressor Polycomb 2/genética , Complexo Repressor Polycomb 2/fisiologia , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas c-akt/fisiologia , Piridonas/uso terapêutico
4.
Phytother Res ; 33(10): 2775-2782, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31373419

RESUMO

Diabetic nephropathy (DN) is one of the major complications of diabetes mellitus. The progression of DN has been found to be associated with high glucose (HG)-induced oxidative stress and inflammation in diabetes mellitus. Eriodictyol is a flavonoid that possesses antioxidant and anti-inflammatory effects. However, the effect of eriodictyol on DN remains unknown. In the present study, we evaluated the role of eriodictyol in mesangial cells (MCs) in response to HG condition. The results showed that eriodictyol repressed cell proliferation of HG-stimulated MCs. Treatment with eriodictyol attenuated oxidative stress, which was evidenced by increased superoxide dismutase activity as well as decreased production of reactive oxygen species (ROS) and malondialdehyde. Besides, eriodictyol suppressed the expressions of two NADPH oxidase (NOX) isoforms, NOX2 and NOX4, which are responsible for the generation of ROS. Eriodictyol suppressed the production of extracellular matrix proteins including fibronectin and Collagen IV, as well as the secretion of inflammatory cytokines including TNF-α, IL-1ß, and IL-6 in HG-induced MCs. Moreover, the HG-induced activation of Akt/NF-κB pathway was mitigated by eriodictyol. In conclusion, eriodictyol protected MCs from HG stimulation though inhibition of Akt/NF-κB pathway.


Assuntos
Matriz Extracelular/metabolismo , Flavanonas/farmacologia , Inflamação/prevenção & controle , Células Mesangiais/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Células Cultivadas , Citocinas/metabolismo , Matriz Extracelular/efeitos dos fármacos , Fibronectinas/metabolismo , Humanos , Células Mesangiais/metabolismo , NF-kappa B/antagonistas & inibidores , NF-kappa B/fisiologia , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/fisiologia
5.
Biochimie ; 165: 229-234, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31401189

RESUMO

Epithelial-mesenchymal transition (EMT) is a critical process in the development of many tissues and organs in multicellular organisms that its important role in the pathogenesis of metastasis and tumor cell migration has been firmly established. Decreased adhesive capacity, cytoskeletal reorganization, and increased mobility are hallmarks of the EMT. Several molecular mechanisms promote EMT, Including regulation of the levels of specific cell-surface proteins, ECM-degrading enzymes, and altering the expression of certain transcription factors and microRNAs. EMT process is modulated through multiple signaling pathways including the AKT/mTOR pathway. AKT is a key component in numerous processes which was recently shown to regulate the EMT through suppression of the expression of E-cadherin via EMT transcription factors. On the other hand, mTOR complexes can also regulate the EMT through the regulation of cell's actin cytoskeleton by altering the PKC phosphorylation state and direct phosphorylation and activation of Akt. Here we review the effect of AKT and mTOR on EMT and consequently metastasis and cell motility.


Assuntos
Transição Epitelial-Mesenquimal/fisiologia , Proteínas Proto-Oncogênicas c-akt/fisiologia , Serina-Treonina Quinases TOR/fisiologia , Movimento Celular/fisiologia , Humanos , Metástase Neoplásica/patologia , Transdução de Sinais
6.
J Mol Histol ; 50(4): 369-374, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31190160

RESUMO

The first cell lineage differentiation occurs during the development of mouse 8-cell embryo to blastocyst. Akt is a potent kinase whose role during blastocyst formation has not been elucidated. In the present study, immunofluorescence results showed that the Akt protein was specifically localized to the outer cells of the morula. Akt-specific inhibitor MK2206 significantly inhibited mouse blastocyst formation and resulted in decreased expression of the trophectoderm marker Cdx2 and led to granular distribution of ERα in the cytoplasm. Furthermore, knockdown of ERα by siRNA microinjection can also lead to a decrease in the development rate of mouse blastocysts, accompanied by a decrease in the expression level of Yap protein. We conclude that Akt may be indispensable for the first cell lineage differentiation of mouse.


Assuntos
Diferenciação Celular , Linhagem da Célula , Embrião de Mamíferos/citologia , Proteínas Proto-Oncogênicas c-akt/fisiologia , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Blastocisto/citologia , Proteínas de Ciclo Celular/metabolismo , Desenvolvimento Embrionário , Regulação da Expressão Gênica no Desenvolvimento , Camundongos , Mórula/química
7.
BMC Ophthalmol ; 19(1): 130, 2019 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-31208396

RESUMO

BACKGROUND: Nerve growth factor (NGF), produced by Müller cells, and internal limiting membrane (ILM) have fundamental roles in the development of full-thickness macular hole (FTMH). However, the potential crosstalk between NGF and ILM in FTMH is unclear. This study aimed to explore the mechanism and effects of NGF on the proliferation of Müller cells co-cultured with ILM. METHODS: Primary Müller cells and ILM from New Zealand rabbits were extracted and authenticated with specific staining. Müller cells co-cultured with or without ILM were exposed to NGF and then analysed. Müller cell viability was estimated using cell counting kit-8. Cell cycle analysis was performed by flow cytometry. The levels of cell cycle-related gene were detected using qRT-PCR. The TrK-A/Akt signal axis and downstream signaling cascades such as p21, CyclinE, CDK2, CyclinD1, and CDK4 were investigated by western blotting. RESULTS: ILM treatment alone induced the proliferation of Müller cells following the promotion of phosphorylated Akt, while growth of Müller cells was enhanced by activation of the Trk-A/Akt pathway under the stimulation of NGF or NGF + ILM. Additionally, the ratio of S-phase cells was increased, while G2-phase cells decreased upon the treatment with either ILM or NGF alone, or with NGF + ILM co-treatment. Cell cycle-related genes such as CyclinD1, CyclinE, CDK2, and CDK4 were all upregulated, but p21 expression was downregulated in the presence of NGF, ILM, or NGF + ILM. There was an additive effect on cell proliferation and cell cycle in the group of Müller cells exposed to NGF co-cultured with ILM compared with either NGF or ILM treatment alone. However, both K252ɑ (inhibitors of Trk-A) and LY294002 (inhibitor for Akt) counteracted the effect of NGF or NGF + ILM on the protein levels of Trk-A, Akt, CyclinD1, CyclinE, CDK2, and p21. CONCLUSIONS: Müller cells co-cultured with ILM or NGF promoted cell proliferation by regulating cell cycle-correlated proteins via the PI3K/Akt pathway. ILM + NGF further amplified the PI3K/Akt signaling pathway by binding to Trk-A, leading to more cell growth. This study provides new insight into the potential mechanism of NGF-mediated proliferation of Müller cells co-cultured with or without ILM, which may have considerable impact on therapies for FTMH.


Assuntos
Membrana Basal , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Ependimogliais/efeitos dos fármacos , Fator de Crescimento Neural/farmacologia , Fosfatidilinositol 3-Quinases/fisiologia , Proteínas Proto-Oncogênicas c-akt/fisiologia , Animais , Membrana Basal/efeitos dos fármacos , Membrana Basal/fisiologia , Técnicas de Cocultura , Células Ependimogliais/citologia , Coelhos
8.
Int Urol Nephrol ; 51(6): 1071-1078, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31089945

RESUMO

PURPOSE: The aim of this study was to investigate the effects and possible mechanism of tea polyphenols (TPs) on the senescence of human glomerular mesangial cells (HGMCs) under high glucose conditions. METHODS: HGMCs were divided into the normal group (NG, 5.5 mmol/L glucose), mannitol group (MNT, 5.5 mmol/L glucose and 24.5 mmol/L mannitol), TP group (TP, 30 mmol/L glucose and 5 µg/mL TP) and high-dose D-glucose group (HG, 30 mmol/L glucose). The effects of TP on the cell morphology of HGMCs; the percentage of cells positive for senescence-associated ß-galactosidase (SA-ß-gal); the ratio of G1 phase of cell cycle; telomere length; and the expression of p-Akt, p53, p21 and Rb proteins of the Akt-p53-p21 signaling pathway and the expression miR-126 were examined. RESULTS: High glucose led to premature senescence of HGMCs, as evident from the increase in the percentage of SA-ß-gal-positive cells, decrease in telomere length, cell cycle arrest at G1 phase,decrease in the expression of miR-126 and p-Akt and increase in the expression of p53, p21 and Rb proteins in the HG group. In contrast, in the TP group, these effects of high glucose treatment were abrogated and this indicates that TP had a protective effect on HGMCs. CONCLUSIONS: High glucose induces the senescence of HGMCs in vitro via the miR-126 and Akt-p53-p21 signaling pathways. TP can delay the high glucose-induced senescence of HGMCs by regulating the activity of these signaling pathways. Thus, the polyphenols present in tea may have potential for the treatment of diabetic nephropathies associated with premature senescence.


Assuntos
Senescência Celular/efeitos dos fármacos , MicroRNAs/fisiologia , Polifenóis/farmacologia , Proteínas Proto-Oncogênicas c-akt/fisiologia , Proteína Supressora de Tumor p53/fisiologia , Células Cultivadas , Humanos , Hiperglicemia , Células Mesangiais , Transdução de Sinais , Chá
9.
Arterioscler Thromb Vasc Biol ; 39(7): 1458-1474, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31092013

RESUMO

Objective- In response to tissue injury, the appropriate progression of events in angiogenesis is controlled by a careful balance between pro and antiangiogenic factors. We aimed to identify and characterize microRNAs that regulate angiogenesis in response to tissue injury. Approach and Results- We show that in response to tissue injury, microRNA-615-5p (miR-615-5p) is rapidly induced and serves as an antiangiogenic microRNA by targeting endothelial cell VEGF (vascular endothelial growth factor)-AKT (protein kinase B)/eNOS (endothelial nitric oxide synthase) signaling in vitro and in vivo. MiR-615-5p expression is increased in wounds of diabetic db/db mice, in plasma of human subjects with acute coronary syndromes, and in plasma and skin of human subjects with diabetes mellitus. Ectopic expression of miR-615-5p markedly inhibited endothelial cell proliferation, migration, network tube formation in Matrigel, and the release of nitric oxide, whereas miR-615-5p neutralization had the opposite effects. Mechanistic studies using transcriptomic profiling, bioinformatics, 3' untranslated region reporter and microribonucleoprotein immunoprecipitation assays, and small interfering RNA dependency studies demonstrate that miR-615-5p inhibits the VEGF-AKT/eNOS signaling pathway in endothelial cells by targeting IGF2 (insulin-like growth factor 2) and RASSF2 (Ras-associating domain family member 2). Local delivery of miR-615-5p inhibitors, markedly increased angiogenesis, granulation tissue thickness, and wound closure rates in db/db mice, whereas miR-615-5p mimics impaired these effects. Systemic miR-615-5p neutralization improved skeletal muscle perfusion and angiogenesis after hindlimb ischemia in db/db mice. Finally, modulation of miR-615-5p expression dynamically regulated VEGF-induced AKT signaling and angiogenesis in human skin organoids as a model of tissue injury. Conclusions- These findings establish miR-615-5p as an inhibitor of VEGF-AKT/eNOS-mediated endothelial cell angiogenic responses and that manipulating miR-615-5p expression could provide a new target for angiogenic therapy in response to tissue injury. Visual Overview- An online visual overview is available for this article.


Assuntos
Células Endoteliais/fisiologia , MicroRNAs/fisiologia , Neovascularização Fisiológica , Óxido Nítrico Sintase Tipo III/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Animais , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Óxido Nítrico Sintase Tipo III/fisiologia , Fosforilação , Proteínas Proto-Oncogênicas c-akt/fisiologia , Transdução de Sinais/fisiologia , Proteínas Supressoras de Tumor/fisiologia , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Fator A de Crescimento do Endotélio Vascular/fisiologia
10.
Oncogene ; 38(26): 5321-5337, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30971761

RESUMO

In IBD patients, integration between a hyper-activated immune system and epithelial cell plasticity underlies colon cancer development. However, molecular regulation of such a circuity remains undefined. Claudin-1 (Cld-1), a tight-junction integral protein deregulation alters colonic epithelial cell (CEC) differentiation, and promotes colitis severity while impairing colitis-associated injury/repair. Tumorigenesis is a product of an unregulated wound-healing process and therefore we postulated that upregulated Cld-1 levels render IBD patients susceptible to the colitis-associated cancer (CAC). Villin Cld-1 mice are used to carryout overexpressed studies in mice. The role of deregulated Cld-1 expression in CAC and the underlying mechanism was determined using a well-constructed study scheme and mouse models of DSS colitis/recovery and CAC. Using an inclusive investigative scheme, we here report that upregulated Cld-1 expression promotes susceptibility to the CAC and its malignancy. Increased mucosal inflammation and defective epithelial homeostasis accompanied the increased CAC in Villin-Cld-1-Tg mice. We further found significantly increased levels of protumorigenic M2 macrophages and ß-cateninSer552 (ß-CatSer552) expression in the CAC in Cld-1Tg vs. WT mice. Mechanistic studies identified the role of PI3K/Akt signaling in Cld-1-dependent activation of the ß-CatSer552, which, in turn, was dependent on proinflammatory signals. Our studies identify a critical role of Cld-1 in promoting susceptibility to CAC. Importantly, these effects of deregulated Cld-1 were not associated with altered tight junction integrity, but on its noncanonical role in regulating Notch/PI3K/Wnt/ ß-CatSer552 signaling. Overall, outcome from our current studies identifies Cld-1 as potential prognostic biomarker for IBD severity and CAC, and a novel therapeutic target.


Assuntos
Claudina-1/genética , Colite/complicações , Neoplasias do Colo/etiologia , Proteínas Proto-Oncogênicas c-akt/fisiologia , Receptores Notch/fisiologia , beta Catenina/metabolismo , Animais , Biomarcadores Tumorais/genética , Células Cultivadas , Colite/diagnóstico , Colite/genética , Colite/metabolismo , Neoplasias do Colo/diagnóstico , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , Regulação Neoplásica da Expressão Gênica , Células HT29 , Humanos , Doenças Inflamatórias Intestinais/complicações , Doenças Inflamatórias Intestinais/diagnóstico , Doenças Inflamatórias Intestinais/genética , Doenças Inflamatórias Intestinais/patologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Fosforilação , Prognóstico , Processamento de Proteína Pós-Traducional , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores Notch/metabolismo , Transdução de Sinais/genética , Regulação para Cima/genética
11.
Oncogene ; 38(26): 5250-5264, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30894683

RESUMO

As a transcription factor critical for embryonic and adult stem cell self-renewal and function, SOX2 gene amplification has been recognized as a driving factor for various cancers including esophageal cancer. SOX2 overexpression occurs more broadly in cancer than gene amplification, but the mechanism is poorly understood. Here we showed that in esophageal cancer cell lines the levels of SOX2 proteins are not directly correlated to the copy numbers of SOX2 genes and are strongly influenced by proteostasis. We showed that AKT is a major determinant for SOX2 overexpression and does so by protecting SOX2 from ubiquitin-dependent protein degradation. We identified UBR5 as a major ubiquitin E3 ligase that induces SOX2 degradation through ubiquitinating SOX2 at lysine 115. Phosphorylation of SOX2 at threonine 116 by AKT inhibits the interaction of UBR5 with SOX2 and thus stabilizes SOX2. We provided evidence that AKT inhibitor can effectively downregulate SOX2 and suppress esopheageal cancer cell proliferation and stemness. Taken together, our study provides new insight into the mechanism of SOX2 overexpression in cancer and evidence for targeting AKT as a potential therapeutic strategy for SOX2-positive cancers.


Assuntos
Neoplasias Esofágicas/patologia , Células-Tronco Neoplásicas/patologia , Proteínas Proto-Oncogênicas c-akt/fisiologia , Fatores de Transcrição SOXB1/genética , Fatores de Transcrição SOXB1/metabolismo , Ubiquitina-Proteína Ligases/fisiologia , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/metabolismo , Amplificação de Genes , Dosagem de Genes , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Humanos , Células-Tronco Neoplásicas/metabolismo , Proteólise , Células Tumorais Cultivadas , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação , Regulação para Cima/genética
12.
Gene ; 698: 120-128, 2019 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-30849534

RESUMO

Phosphatidylinositol 3-kinases (PI3Ks) are crucial coordinators of intracellular signalling in response to the extracellular stimulators. Hyperactivation of PI3K signalling cascades is one among the most ordinary events in human cancers. Focusing on the PI3K pathway remains both a chance and a challenge for cancer therapy. The high recurrence of phosphoinositide 3-kinase (PI3K) pathway adjustments in cancer has led to a surge in the progression of PI3K inhibitors. Recent developments incorporate a re-assessment of the oncogenic mechanisms behind PI3K pathway modifications. Receptor tyrosine kinases upstream of PI3K, the p110a catalytic fractional unit of PI3K, the downstream kinase, AKT, and therefore the negative regulator, PTEN, are all often altered in cancer. In this review, we consider about the phosphoinositide 3-kinases family and mechanisms of PI3K-Akt stimulation in cancer.


Assuntos
Neoplasias/metabolismo , Fosfatidilinositol 3-Quinases/fisiologia , Proteínas Proto-Oncogênicas c-akt/fisiologia , Classe I de Fosfatidilinositol 3-Quinases/metabolismo , Humanos , Recidiva Local de Neoplasia/metabolismo , PTEN Fosfo-Hidrolase/metabolismo , Inibidores de Proteínas Quinases/metabolismo , Receptores Proteína Tirosina Quinases/fisiologia , Transdução de Sinais/fisiologia , Serina-Treonina Quinases TOR/fisiologia
13.
Pestic Biochem Physiol ; 154: 67-77, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30765058

RESUMO

The ß-carboline alkaloids are a large group of naturally occurring and synthetic indole alkaloids with remarkable pharmacological properties. Furthermore, these alkaloids have also been reported to be effective agents for controlling many pests and plant pathogenic nematodes. However, studies on these potential insecticidal components are scarce. The previous finding that these bioactive compounds can induce programmed cell death in cancer cell lines provided a new insight for exploration of their toxicological mechanisms on insects. In the present study, the cytotoxicity of five natural harmala alkaloids was measured, and the autophagy-inducing effect was confirmed in the Spodoptera frugiperda Sf9 cultured cell line. The results demonstrated that these alkaloids inhibited the proliferation of Sf9 cells in a dose- and time-dependent manner, and the unsaturated ß-carboline alkaloids, harmine and harmol, exhibited stronger autophagy induction activity based on monodansylcadaverineand LysoTracker Red staining. Many autophagy-related genes were increased after ß-carbolines treatment at the RNA level, and the protein expression of Sf-Atg8 was also confirmed to increase after treatment. In addition, the primary autophagic signaling pathway, the PI3K/Akt/mTOR pathway, was altered during the procedure. Furthermore, experiments with special inhibitors and activators were performed to confirm the effect of ß-carbolines on this pathway. The results suggested that the PI3K/Akt/mTOR pathway primarily regulated harmine-induced autophagy in insect cells, and this finding may potentially benefit the application of these promising bioactivity components.


Assuntos
Alcaloides/farmacologia , Autofagia/efeitos dos fármacos , Carbolinas/farmacologia , Fosfatidilinositol 3-Quinases/fisiologia , Proteínas Proto-Oncogênicas c-akt/fisiologia , Serina-Treonina Quinases TOR/fisiologia , Animais , Células Sf9 , Transdução de Sinais/efeitos dos fármacos , Spodoptera
14.
Acta Cir Bras ; 34(1): e20190010000005, 2019 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-30785506

RESUMO

PURPOSE: To investigate the role of PI3k/Akt signal pathway in the protective effects of propofol on intestinal and lung injury induced by intestinal ischemia/reperfusion(I/R). METHODS: Male Sprague-Dawley rats were subjected to 45 min of ischemia by occluding the superior mesenteric artery and to 2h of reperfusion to establish the model of I/R. Twenty four rats were randomly divided into four groups: Sham, intestinal I/R (II/R), propofol (P), wortmannin (W). In groups P, W, propofol was injected intravenously and continuously at the onset of reperfusion via infusion pump. PI3K inhibitor (wortmannin) was administered intravenously in group W 25 min before ischemia. Intestinal tissues and lung tissues were obtained for determination of histologic injury, wet/dry weight ratio, malondialdehyde (MDA) levels, superoxide dismutase (SOD) and myeloperoxidase (MPO) activities. Meanwhile, the expressions of caspase-3 and phosphorylated Akt (p-Akt) in intestines and lungs were detected by western blot. RESULTS: Propofol treatment alleviated intestinal and lung morphological changes which were observed in II/R group,Moreover, wet/dry weight ratio, the MDA level, MPO activity and expression of caspase-3 were significantly decreased whereas the SOD activity and p-Akt expression were significantly increased. Notably, the protections were significantly reversed by pretreatment of wortmannin. CONCLUSION: PI3K/Akt pathway activation play a critical role in the protective effects of propofol on intestinal and lung injury induced by ischemia/reperfusion.


Assuntos
Anestésicos Intravenosos/farmacologia , Lesão Pulmonar/prevenção & controle , Isquemia Mesentérica/tratamento farmacológico , Fosfatidilinositol 3-Quinases/fisiologia , Propofol/farmacologia , Proteínas Proto-Oncogênicas c-akt/fisiologia , Traumatismo por Reperfusão/tratamento farmacológico , Animais , Modelos Animais de Doenças , Masculino , Isquemia Mesentérica/metabolismo , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/metabolismo , Transdução de Sinais/fisiologia
15.
J Environ Pathol Toxicol Oncol ; 38(1): 69-81, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30806292

RESUMO

The risk of cancer development in offspring due to carcinogen exposure during pregnancy is a serious issue. In this study, we explored the involvement of the phosphatidylinositol 3-kinase (PI3K)/Akt pathway and microRNA-21 (miR-21) in transplacental lung tumorigenesis and its prevention by dietary compound inositol hexaphosphate (IP6) in F1 mice. Balb/c mice were exposed to the N-ethyl-N-nitrosourea (ENU) intraperitoneally on the 17th day of gestation. After weaning, half of the litters were fed with oral 2% IP6. At the end of 30, 120, or 240 days, we did not observe any effect on fetal viability or weight between ENU-exposed and non-exposed litters and the same was true of IP6. Altered expressions of the PI3K/Akt pathway were observed in F1 mice. Further, miR-21 expressions were found to be modulated at the respective time as well, along with the activation of matrix metalloproteinase (MMP-9) and vascular endothelial growth factor expression. Akt activation also enhanced the expression of cyclin D1, cyclooxygenase-2 (COX-2), nuclear factor-κB (NF-κBp50), and mammalian target of rapamycin (mTOR). IP6-fed F1 mice showed reduced tumorigenesis along with reduced expression of the PI3K/Akt pathway miR-21 and downstream targets. The PI3K/Akt pathway and miR-21 are involved in transplacental lung tumorigenesis, whereas IP6 seemed to affect lung tumorigenesis by suppressing the expression of the PI3K/Akt pathway in F1 mice.


Assuntos
Neoplasias Pulmonares/metabolismo , MicroRNAs/fisiologia , Fosfatidilinositol 3-Quinases/fisiologia , Ácido Fítico/farmacologia , Proteínas Proto-Oncogênicas c-akt/fisiologia , Animais , Carcinogênese/efeitos dos fármacos , Carcinogênese/genética , Feminino , Neoplasias Pulmonares/patologia , Camundongos Endogâmicos BALB C , MicroRNAs/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo
16.
Biol Res ; 52(1): 8, 2019 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-30808417

RESUMO

BACKGROUND: Cervical cancer (CC) ranks third in the morbidity and mortality of female cancer around the world. Derlin1 has been found to be overexpressed in several human cancers. However, it is still unclear about its roles in CC. The research aims to explore the relationship between Derlin1 and CC. METHODS: We purchased a human CC tissues microarray, which contained CC tissues and corresponding para-cancerous tissues from 93 patients with primary cervical squamous cell carcinoma. Immunohistochemical staining was used to confirm the expression of Derlin1 in these tissues. And we detected the differential expression of Derlin1 in cervical cancer cell lines and normal cervical epithelial cells (H8). Further, the cervical cancer cell lines SiHa and C33A were used as an in vitro model, which was down-regulated the expression of Derlin1 using siRNA interference technology. The effects of Derlin1 down-regulating in CC cell lines on cell proliferation and migration were detected by CCK8 assay and transwell assay, respectively. The effect of Derlin1 down-regulating on apoptosis was analyzed by flow cytometry, and apoptosis-related proteins were detected using western blotting. In-depth mechanisms were studied using western blotting. In addition, the effects of Derlin1 up-regulating in normal cervical epithelial cells also were exposed. RESULTS: Derlin1 was significantly elevated in CC tissues (81.7%, 76/93), and the expression of Derlin1 was positively correlated with the tumor size, pathological grade, and lymph node metastasis in CC patients. And Derlin1 was high expressed in cervical cancer cell lines compared to H8 cells. Knockdown of Derlin1 in cervical cancer cell lines inhibited cell proliferation and migration. Moreover, knockdown of Derlin1 induced apoptosis and affected the expression of apoptosis-related proteins, including Bcl-2, Bax, Bim, caspase3 and caspase9. Further experiments showed that AKT/mTOR signal pathway might be involve in this processes that knockdown of Derlin1 inhibited the expression of p-AKT and p-mTOR. Over-expression of Derlin1 in H8 cells promoted cell proliferation and migration via up-regulated the expression of p-AKT and p-mTOR. CONCLUSION: Derlin1 is an oncogene in CC via AKT/mTOR pathway. It might be a potential therapeutic target for CC.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Proteínas de Membrana/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/fisiologia , Serina-Treonina Quinases TOR/metabolismo , Neoplasias do Colo do Útero/metabolismo , Apoptose , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Humanos , Imuno-Histoquímica , Análise Serial de Proteínas , Proteínas Proto-Oncogênicas c-akt/fisiologia , Neoplasias do Colo do Útero/patologia
17.
Chin Med J (Engl) ; 132(4): 454-465, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30707166

RESUMO

BACKGROUND: Long noncoding RNAs (lncRNAs) play pivotal roles in various malignant tumors. Epidermal growth factor receptor (EGFR) signaling is associated with the pathogenesis of cutaneous squamous cell carcinoma (cSCC). This study aimed to explore the role of LINC00520 in the development of cSCC via EGFR and phosphoinositide 3-kinase-protein kinase B (PI3K/Akt) signaling pathways. METHODS: A microarray analysis was applied to screen differentially expressed lncRNAs in cSCC samples. The A431 cSCC cell line was transfected and assigned different groups. The expression patterns of LINC00520, EGFR, and intermediates in the PI3K/Akt pathway were characterized using reverse transcription quantitative polymerase chain reaction (RT-qPCR) and Western blotting analysis. Cell proliferation, migration, and invasion were detected using the MTT assay, scratch test, and Transwell assay, respectively. Cell-based experiments and a tumorigenicity assay were conducted to assess the effect of LINC00520 on cSCC progression. This study was ended in September 2017. Comparisons between two groups were analyzed with t-test and comparisons among multiple groups were analyzed using one-way analysis of variance. The nonparametric Wilcoxon rank sum test was used to analyze skewed data. The enumerated data were analyzed using the chi-square test or Fisher exact test. RESULTS: Data from chip GSE66359 revealed depletion of LINC00520 in cSCC. Cells transfected with LINC00520 vector and LINC00520 vector + si-EGFR showed elevated LINC00520 level but decreased levels of the EGFR, PI3K, AKT, VEGF, MMP-2 and MMP-9 mRNAs and proteins, and inhibition of the growth, migration and adhesion of cSCC cells, while the si-LINC00520 group showed opposite trends (all P < 0.05). Compared with the LINC00520 vector group, the LINC00520 vector + si-EGFR group showed decreased levels of the EGFR, PI3K, AKT, VEGF, MMP-2 and MMP-9 mRNAs and proteins, and inhibition of the growth, migration and adhesion of cSCC cells, while the LINC00520 vector + EGFR vector group showed opposite results (all P < 0.05). CONCLUSION: Based on our results, LINC00520-targeted EGFR inhibition might result in the inactivation of the PI3K/Akt pathway, thus inhibiting cSCC development.


Assuntos
Carcinoma de Células Escamosas/prevenção & controle , Receptores ErbB/antagonistas & inibidores , Fosfatidilinositol 3-Quinases/fisiologia , Proteínas Proto-Oncogênicas c-akt/fisiologia , RNA Longo não Codificante/fisiologia , Transdução de Sinais/fisiologia , Neoplasias Cutâneas/prevenção & controle , Animais , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Progressão da Doença , Feminino , Humanos , Metástase Linfática , Camundongos , Invasividade Neoplásica , Neoplasias Cutâneas/patologia
18.
Glia ; 67(7): 1277-1295, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30761608

RESUMO

Multiple extracellular and intracellular signals regulate the functions of oligodendrocytes as they progress through the complex process of developmental myelination and then maintain a functionally intact myelin sheath throughout adult life, preserving the integrity of the axons. Recent studies suggest that Mek/ERK1/2-MAPK and PI3K/Akt/mTOR intracellular signaling pathways play important, often overlapping roles in the regulation of myelination. However, it remains poorly understood whether they function independently, sequentially, or converge using a common mechanism to facilitate oligodendrocyte differentiation, myelin growth, and maintenance. To address these questions, we analyzed multiple genetically modified mice and asked whether the deficits due to the conditional loss-of-function of ERK1/2 or mTOR could be abrogated by simultaneous constitutive activation of PI3K/Akt or Mek, respectively. From these studies, we concluded that while PI3K/Akt, not Mek/ERK1/2, plays a key role in promoting oligodendrocyte differentiation and timely initiation of myelination through mTORC1 signaling, Mek/ERK1/2-MAPK functions largely independently of mTORC1 to preserve the integrity of the myelinated axons during adulthood. However, to promote the efficient growth of the myelin sheath, these two pathways cooperate with each other converging at the level of mTORC1, both in the context of normal developmental myelination or following forced reactivation of the myelination program during adulthood. Thus, Mek/ERK1/2-MAPK and the PI3K/Akt/mTOR signaling pathways work both independently and cooperatively to maintain a finely tuned, temporally regulated balance as oligodendrocytes progress through different phases of developmental myelination into adulthood. Therapeutic strategies aimed at targeting remyelination in demyelinating diseases are expected to benefit from these findings.


Assuntos
MAP Quinase Quinase Quinases/fisiologia , Sistema de Sinalização das MAP Quinases/fisiologia , Bainha de Mielina/fisiologia , Fosfatidilinositol 3-Quinases/fisiologia , Proteínas Proto-Oncogênicas c-akt/fisiologia , Serina-Treonina Quinases TOR/fisiologia , Fatores Etários , Animais , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Fibras Nervosas Mielinizadas/fisiologia , Transdução de Sinais/fisiologia
19.
Phytother Res ; 33(3): 768-778, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30637828

RESUMO

Total aralosides of Aralia elata (Miq) Seem (TASAESs) possess multiple pharmacological activity, such as anti-inflammation, antioxidation, and antiapoptosis. However, there is no literature reporting the antiatherosclerotic effect and mechanism of TASAES so far. The aim of this study was to investigate the antiatherosclerotic effects in high-fat diet-induced ApoE-/- mice and potential mechanism of TASAES in ox-LDL-injured endothelial cells. In vivo assay, our data demonstrated that TASAES significantly reduced the atherosclerotic plaque size and caspase-3 expression level in aortic valve. In vitro, we found that TASAES could increase endothelial cell viability, attenuated mitochondrial membrane potential depolarization, and endothelial cells apoptosis. In addition, we found that TASAES could activate SIRT1/AMPK and Akt/eNOS signaling pathways. Importantly, EX527, SIRT1 siRNA, and LY294002, Akt siRNA, remarkably abolished the antiapoptotic effects of TASAES. In conclusion, this study demonstrated that SIRT1/AMPK and Akt/eNOS signaling pathways are involved in endothelial protection of TASAES against atherosclerotic mice, suggesting that TASAES is a candidate drug for atherosclerosis treatment.


Assuntos
Proteínas Quinases Ativadas por AMP/fisiologia , Aralia/química , Aterosclerose/tratamento farmacológico , Células Endoteliais/efeitos dos fármacos , Óxido Nítrico Sintase Tipo III/fisiologia , Proteínas Proto-Oncogênicas c-akt/fisiologia , Saponinas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Sirtuína 1/fisiologia , Animais , Apolipoproteínas E/fisiologia , Aterosclerose/etiologia , Dieta Hiperlipídica , Masculino , Camundongos , Camundongos Endogâmicos C57BL
20.
Invest Ophthalmol Vis Sci ; 60(1): 82-92, 2019 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-30640966

RESUMO

Purpose: Profibrotic activation is essential for pterygium development. In this study, we investigated the role of the mechanistic target of rapamycin (mTOR) in regulating TGF-ß1-induced myofibroblastic responses in human pterygium fibroblasts (HPFs) and elucidated the relative contributions of mTOR signaling components. Methods: HPFs were pretreated with the mTOR inhibitors rapamycin and Torin2, and TGF-ß1-induced expression of profibrotic markers, including α-smooth muscle actin (α-SMA) and fibronectin, was evaluated. RNA interference-based approaches targeting raptor and rictor, regulatory subunits of mTOR complex 1 (mTORC1) and 2 (mTORC2), respectively, were used to determine the impact of each mTOR complex on HPFs. The contractile phenotype of HPFs was assessed by a collagen gel contraction assay. Results: The mTOR active-site inhibitor Torin2, which suppresses both mTORC1 and mTORC2 activity in HPFs, inhibited TGF-ß1-induced expression of α-SMA and fibronectin. The allosteric inhibitor rapamycin only partially suppressed mTORC1 activity and exhibited a minimal effect on the induction of profibrotic markers. The induction of α-SMA and fibronectin in HPFs was abrogated by RNA interference-mediated knockdown of rictor but was only moderately affected by raptor knockdown. Akt inhibition mimicked the effect of Torin2 and rictor knockdown on myofibroblast differentiation of HPFs. mTOR inhibition potently reduced the contractile ability of HPFs in collagen gel contraction assays. Conclusions: This study found that mTOR signaling promoted profibrotic activation of HPFs and confirmed the importance of the mTORC2-Akt axis in TGF-ß1-induced myofibroblast differentiation. Therefore, our study may open up new avenues for the development of novel therapeutic strategies involving targeting of mTOR signaling to treat pterygium.


Assuntos
Diferenciação Celular/fisiologia , Fibroblastos/metabolismo , Alvo Mecanístico do Complexo 2 de Rapamicina/fisiologia , Miofibroblastos/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/fisiologia , Pterígio/metabolismo , Transdução de Sinais/fisiologia , Fator de Crescimento Transformador beta1/farmacologia , Actinas/metabolismo , Adulto , Idoso , Western Blotting , Fibronectinas/metabolismo , Citometria de Fluxo , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Pessoa de Meia-Idade , Naftiridinas/farmacologia , Interferência de RNA , Reação em Cadeia da Polimerase em Tempo Real , Sirolimo/farmacologia , Fator de Crescimento Transformador beta1/antagonistas & inibidores
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