scholarly journals PI3K/Akt inhibitor partly decreases TNF-α-induced activation of fibroblast-like synoviocytes in osteoarthritis

2019 ◽  
Vol 14 (1) ◽  
Author(s):  
Songyang Liu ◽  
Chenxi Cao ◽  
Yujun Zhang ◽  
Guangyu Liu ◽  
Weixia Ren ◽  
...  
Keyword(s):  
Cartilage Damage ◽  
Inhibitory Effect ◽  
Pi3k Inhibitor ◽  
Akt Pathway ◽  
Akt Inhibitor ◽  
Pi3k Inhibitor Ly294002 ◽  
Tnf Α ◽  
Invasive Capacity ◽  
And Cartilage ◽  
Fibroblast Like Synoviocytes

Abstract Background The Cadherin-11 and PI3K/Akt pathway are increasingly recognized as the potential therapeutic target of osteoarthritis (OA) synovitis. The study aimed to investigate the role of PI3K/Akt signaling pathway in the expression of Cadherin-11 and migration and invasive capacity of fibroblast-like synoviocytes (FLS) of OA patients under stimulation of TNF-α and to explore the effect of the PI3K/Akt inhibitor and Cadherin-11 antibody in the therapy of the collagenase-induced osteoarthritis (CIOA) mice. Methods FLS were primarily cultured from synovium of osteoarthritic patients during total knee arthroplasty. Under the simulation of TNF-α, with or without PI3K/Akt inhibitor LY294002, Cadherin-11 expression was detected by real-time PCR and Western blot, as well as the migration and invasive capacity changes of OA FLS. Cadherin-11 antibody was injected intraarticularly or LY294002 was injected intraperitoneally in CIOA mice to evaluate the changes of synovitis score, cartilage damage, and Cadherin-11 expression. Results TNF-α stimulation increased Cadherin-11 expression at mRNA and protein level in OA FLS and also increased the phosphorylation-dependent activation of Akt. PI3K inhibitor LY294002 attenuated TNF-α-induced overexpression of Cadherin-11 and decreased the invasive capacity of OA FLS. Intraperitoneal injection of PI3K inhibitor LY294002 could decrease the Cadherin-11 protein expression in synovium of CIOA mice, although it has no significant inhibitory effect on synovitis and cartilage damage. Intraarticular injection of Cadherin-11 antibody attenuated the synovitis and cartilage damage in the CIOA joints and decreased Cadherin-11 expression in the synovial lining. Conclusions PI3K/Akt pathway was associated with TNF-α-induced activation of OA FLS, which may involve in the pathogenesis of osteoarthritis. Anti-Cadherin-11 therapy in CIOA mice could attenuate the pathological changes of OA joints.

Molecular Mechanisms Regulating Resistance to the Akt Inhibitor Perifosine in Waldenstrom’s Macroglobulinemia, the Role of the ERK and PKC Pathways.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 2416-2416
Author(s):  
Xavier Leleu ◽  
Hai Ngo ◽  
Xiaoying Jia ◽  
Anne-Sophie Moreau ◽  
Evdoxia Hatjiharisi ◽  
...  
Keyword(s):  
Molecular Mechanisms ◽  
Mek Inhibitor ◽  
Pi3k Inhibitor ◽  
Erk Pathway ◽  
Waldenström’S Macroglobulinemia ◽  
Akt Inhibitor ◽  
Erk Activation ◽  
Pi3k Inhibitor Ly294002 ◽  
Akt Phosphorylation ◽  
Waldenström's Macroglobulinemia

Abstract Background: We have previously demonstrated activity of the new Akt inhibitor perifosine (NSC 639966; Keryx, NY) in Waldenstrom’s Macroglobulinemia (WM). Perifosine induced complete inhibition of Akt phosphorylation along with induction of apoptosis in WM cells. However, MAPK pathways and PKC proteins were activated in response to perifosine. MAPK and PKC pathways are known to promote cell proliferation. Therefore, understanding the mechanism by which perifosine induces MEK/ERK and PKC activation is important to better understand the mechanisms of response/resistance to this novel agent in ongoing clinical trials. Methods: WM cell lines (BCWM.1, WM-WSU) were treated with perifosine or with the specific Akt inhibitor Triciribine (Biomol, PA). In addition, knockdown of Akt was performed using shRNA silencing techniques (lentivirus shRNA vector, Invitrogen, Ca). The following inhibitors were also used: PI3K inhibitor LY294002 (Calbiochem, CA) and MEK inhibitor (U0126, Calbiochem, CA). Inhibition of proliferation was measured using the MTT assay. Immunoblotting was performed at different time points. Results: Perifosine induced cytotoxicity in WM cells and induced MEK/ERK activation and pPKC activation in a dose and time dependent fashion. We then treated WM cells with perifosine in the presence or absence of the MEK inhibitor U0126 and demonstrated that the combination of the two agents induced significant synergistic activity. We sought to identify the molecular mechanism by which perifosine induces MEK/ERK activation. We demonstrated that the specific AKT inhibitor Triciribine inhibited AKT and induced cytotoxicity in WM cells in a similar fashion to perifosine. However, unlike perifosine, it did not enhance MEK/ERK activity. Similarly, using Akt shRNA, we demonstrated that, despite inhibition of Akt activation, MEK/ERK was not activated. These data indicate that the effect of perifosine on MEK/ERK pathway is not through a compensatory feedback mechanism of Akt inhibition as previously thought. Therefore, we hypothesized that the effect of perifosine on the MEK/ERK pathway is through modulation of upstream pathways, specifically PI3K, PKC and c-Raf/MEK pathways. We first demonstrated that the specific PI3K inhibitor LY294002 (25mM for 15 minutes) completely abrogated Akt phosphorylation, while inducing significant ERK activation, indicating that the effect of perifosine on MEK/ERK may be similar to that of LY294002. We also demonstrated that perifosine and LY294002 activated c-Raf and pan-pPKC at 4 hrs. Conclusion: Based on this, we believe that in the presence of perifosine, growth receptor stimulation leads to PLC and RTK activation, which induces PIP2 stimulation. PIP2 is upstream of PI3K and PKC. Given that PI3K is blocked by perifosine, PIP2 leads to activation of PKC, which then induces growth stimulation, and activation of c-Raf and downstream MEK/ERK. In addition, growth receptors may also activate Raf through the Ras/Raf/MEK pathway, independent of PKC. These studies provide a better understanding of molecular mechanisms that regulate resistance to perifosine. Future combinations of perifosine with MEK inhibitors or PKC inhibitors such as AZD6244 and Enzastaurin may overcome this resistance and induce significant activity in WM.

Inhibition of Akt/Survivin Pathway Synergizes the Antileukemia Effect of Nutlin-3 in Acute Lymphoblastic Leukemia Cells.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 2790-2790
Author(s):  
Ningxi Zhu ◽  
Lubing Gu ◽  
Muxiang Zhou
Keyword(s):  
Acute Lymphoblastic Leukemia ◽  
Cell Lines ◽  
Lymphoblastic Leukemia ◽  
Pi3k Inhibitor ◽  
Pten Expression ◽  
Pten Gene ◽  
Akt Inhibitor ◽  
Cancer Cell Growth ◽  
Pi3k Inhibitor Ly294002 ◽  
Mdm2 Antagonist

PI3k/Akt and p53 pathways are known to play anti- and pro-apoptotic roles in cell death, respectively. High level of PI3k/Akt activation by loss of PTEN expression and inactivation of p53 by overexpression of MDM2 are associated with cancer cell growth and progression. Here, we report that inhibition of PI3k/Akt either by PI3k inhibitor Ly294002 or by expression of PTEN synergizes the MDM2 antagonist nutlin-3 in inducing apoptosis in acute lymphoblastic leukemia (ALL). First, we tested the effect of nutlin-3 on induction of p53 and apoptosis in a set of ALL cell lines with wild-type (wt) p53 and MDM2 overexpression. The p53 was induced by nutlin-3 in all cell lines tested but induction of apoptosis was different in cells with distinct PTEN status. Nutlin-3 induced potent apoptosis in cell lines with PTEN expression but not in cell lines without PTEN expression. Consistent with the apoptotic effects, nutlin-3 significantly downregulated expression of survivin in PTEN-positive cells but not in PTEN-negative cells. When these nutlin-3 resistant cells were simultaneously treated with the PI3K inhibitor Ly294002 or pre-transfected with PTEN gene, their sensitivity to nutlin-3 was increased with a concomitant downregulation of survivin. Furthermore, direct silencing of survivin by siRNA increased the apoptotic effect of nutlin-3 on PTEN-negative ALL cells. Taken together, our results suggest that Akt-mediated survivin upregulation in PTEN-negative ALL cells attenuate nutlin-3 induced apoptosis, and combination of MDM2 antagonist and PI3K/Akt inhibitor may be a promising approach in the treatment of refractory ALL.

scholarly journals Pro-inflammatory cytokine-driven PI3K/Akt/Sp1 signalling and H2S production facilitates the pathogenesis of severe acute pancreatitis

2017 ◽  
Vol 37 (2) ◽  
Author(s):  
Ying Liu ◽  
Ribin Liao ◽  
Zhanrong Qiang ◽  
Cheng Zhang
Keyword(s):  
Acute Pancreatitis ◽  
Severe Acute Pancreatitis ◽  
Rat Model ◽  
Intestinal Motility ◽  
Inhibitory Effect ◽  
Vital Role ◽  
Signalling Pathway ◽  
Pi3k Inhibitor Ly294002 ◽  
Tnf Α ◽  
Bowel Movements

Severe acute pancreatitis (SAP) is a disease usually associated with systemic organ dysfunction or pancreatic necrosis. Most patients with SAP suffer from defective intestinal motility in the early phase of the disease. Additionally, SAP-induced inflammation produces hydrogen sulphide (H2S) that impairs the gastrointestinal (GI) system. However, the exact mechanism of H2S in the regulation of SAP is yet to be elucidated. In the present paper, we used a rat model of SAP to evaluate the role of H2S on intestinal motility by counting the number of bowel movements and investigating the effect of H2S on inflammation. We treated colonic muscle cells (CMCs) with SAP plasma, tumour necrosis factor-α (TNF-α) or interleukin-6 (IL-6) and measured the expressions of H2S-producing enzymes cystathionine-γ-lyase (CSE), cystathionine-β-synthase (CBS) and Sp1 and PI3K/Akt by using quantitative PCR, Western blotting and immunohistochemical detection. We used the PI3K inhibitor LY294002 and the siRNA si-Sp1 to suppress the activity of the PI3K/Akt/Sp1 signalling pathway. We found that, in the SAP rat model, H2S facilitated an inhibitory effect on intestinal motility and enhanced the inflammatory response caused by SAP (P<0.05). The expressions of CSE and CBS in CMCs were significantly increased after treatment with TNF-α or IL-6 (P<0.05). Blocking the PI3K/Akt/Sp1 pathway remarkably inhibited the synthesis of CSE and CBS. Our data demonstrated that H2S plays a vital role in the pathogenesis of SAP and that SAP is modulated by inflammation driven by the PI3K/Akt/Sp1 signalling pathway.

scholarly journals Protective Effect of Fucoidan against MPP+-Induced SH-SY5Y Cells Apoptosis by Affecting the PI3K/Akt Pathway

Marine Drugs ◽  
2020 ◽  
Vol 18 (6) ◽  
pp. 333
Author(s):  
Huaide Liu ◽  
Jing Wang ◽  
Quanbin Zhang ◽  
Lihua Geng ◽  
Yue Yang ◽  
...  
Keyword(s):  
Cell Death ◽  
Protective Effect ◽  
Molecular Mechanisms ◽  
Caspase 3 ◽  
Pi3k Inhibitor ◽  
Neuroprotective Activity ◽  
Akt Pathway ◽  
Cellular Model ◽  
Pi3k Inhibitor Ly294002 ◽  
Cells Death

The main pathologic changes of the Parkinson’s disease (PD) is dopaminergic (DA) neurons lost. Apoptosis was one of the important reasons involved in the DA lost. Our previous study found a fucoidan fraction sulfated heterosaccharide (UF) had neuroprotective activity. The aim of this study was to clarify the mechanism of UF on DA neurons using human dopaminergic neuroblastoma (SH-SY5Y) cells a typical as a PD cellular model. Results showed that UF prevented MPP+-induced SH-SY5Y cells apoptosis and cell death. Additionally, UF pretreated cells increased phosphorylation of Akt, PI3K and NGF, which means UF-treated active PI3K–Akt pathway. Moreover, UF treated cells decreased the expression of apoptosis-associated protein, such as the ratio of Bax/Bcl-2, GSK3β, caspase-3 and p53 nuclear induced by MPP+. This effect was partially blocked by PI3K inhibitor LY294002. Our data suggested that protective effect of UF against MPP+-induced SH-SY5Y cells death by affecting the PI3K–Akt pathway. These findings contribute to a better understanding of the critical roles of UF in treating PD and may elucidate the molecular mechanisms of UF effects in PD.

scholarly journals Effects of adenovirus-mediated knockdown of IRAK4 on synovitis in the osteoarthritis rabbit model

2021 ◽  
Vol 23 (1) ◽  
Author(s):  
Muzhe Li ◽  
Huiyun Li ◽  
Xun Ran ◽  
Han Yin ◽  
Xuling Luo ◽  
...  
Keyword(s):  
Synovial Fluid ◽  
Cruciate Ligament ◽  
Interleukin 1 ◽  
Cartilage Damage ◽  
Rabbit Model ◽  
Joint Disease ◽  
Control Group ◽  
Model Group ◽  
Tnf Α ◽  
And Cartilage

Abstract Background The use of interleukin-1 receptor-associated kinase 4 (IRAK4) inhibitor as a treatment for the inflammatory joint disease is a promising method. However, its underlying mechanism in osteoarthritis (OA) remains unclear. The purpose of this study is to look into the effects of adenovirus-mediated knockdown of IRAK4 on synovitis in the OA rabbit model. Methods Ad-shIRAK4 was injected two weeks after anterior cruciate ligament resection. Six weeks later, the rabbits were killed. The expression of IRAK4, TNFR-associated factor 6(TRAF6), TGF-activated kinase 1(TAK1), p-IKB kinase (p-IKK), p-nuclear factor kappa-B (p-NFκB), p38, and p-p38 in the synovial membrane was detected by western blot, qRT-PCR, and immunohistochemistry analysis. Immunohistochemistry was to detect the expression of IRAK4 proteins in articular cartilage. H&E staining was to assess the pathological changes of synovium and cartilage. The levels of interleukin (IL)-1β, tumor necrosis factor-α(TNF-α), and MMP-13 in the synovial fluid were measured by ELISA. X-ray and micro-computerized tomography (μCT) scans were used to assess knee joint conditions and microstructure of subchondral bone. Results IRAK4 expression levels in synovial tissues of the OA model group exhibited a significant upward trend. Ad-shIRAK4 significantly reduced IRAK4 mRNA expression in synovium tissues. Notably, Ad-shIRAK4 suppressed the Toll-like receptor/interleukin-1 receptor (TLR/IL-1R) signaling. In addition, in the Ad-shIRAK4 treatment group, we can see less inflammatory cell infiltration and reduced hyperplasia and angiogenesis. The levels of IL-1β, TNF-α, and MMP-13 in the synovial fluid in the OA model group were significantly higher than that in the control group, which were reduced by Ad-shIRAK4 treatment. Finally, Results of HE stains, immunohistochemistry, and μCT showed that Ad-shIRAK4 treatment has a protective effect on cartilage damage. Conclusions IRAK4 is significantly upregulated in the synovium from the osteoarthritis rabbit model. In addition, Ad-shIRAK4 reduced the expression of IRAK4 and suppressed TLR/IL-1R signaling in the synovium from the osteoarthritis rabbit model. Ad-shIRAK4 could alleviate synovitis and cartilage degradation in the osteoarthritis rabbit model, and thus alleviate the symptoms of OA and prevent the progression of OA. Graphical abstract

scholarly journals Let-7a-5p regulates the inflammatory response in chronic rhinosinusitis with nasal polyps

2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Jianwei Zhang ◽  
Lei Han ◽  
Feng Chen
Keyword(s):  
Inflammatory Response ◽  
Chronic Rhinosinusitis ◽  
Nasal Polyps ◽  
Mapk Pathway ◽  
Inhibitory Effect ◽  
Luciferase Reporter ◽  
Western Blot Assay ◽  
Protein Levels ◽  
Tnf Α

Abstract Background Let-7a-5p is demonstrated to be a tumor inhibitor in nasopharyngeal carcinoma. However, the role of let-7a-5p in chronic rhinosinusitis with nasal polyps (CRSwNP) has not been reported. This study is designed to determine the pattern of expression and role of let-7a-5p in CRSwNP. Methods The expression level of let-7a-5p, TNF-α, IL-1β, and IL-6 in CRSwNP tissues and cells were detected by RT-qPCR. Western blot assay was carried out to measure the protein expression of the Ras-MAPK pathway. Dual luciferase reporter assay and RNA pull-down assay were used to explore the relationship between let-7a-5p and IL-6. Results Let-7a-5p was significantly downregulated in CRSwNP tissues and cells. Moreover, the mRNA expression of TNF-α, IL-1β and IL-6 was increased in CRSwNP tissues, while let-7a-5p mimic inhibited the expression of TNF-α, IL-1β and IL-6. Besides that, let-7a-5p was negatively correlated with TNF-α, IL-1β and IL-6 in CRSwNP tissues. In our study, IL-6 was found to be a target gene of let-7a-5p. Additionally, let-7-5p mimic obviously reduced the protein levels of Ras, p-Raf1, p-MEK1 and p-ERK1/2, while IL-6 overexpression destroyed the inhibitory effect of let-7a-5p on the Ras-MAPK pathway in CRSwNP. Conclusion We demonstrated that let-7a-5p/IL-6 interaction regulated the inflammatory response through the Ras-MAPK pathway in CRSwNP.

scholarly journals Assessment of PI3K/mTOR/AKT Pathway Elements to Serve as Biomarkers and Therapeutic Targets in Penile Cancer

Cancers ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 2323
Author(s):  
Anita Thomas ◽  
Sascha Reetz ◽  
Philipp Stenzel ◽  
Katrin Tagscherer ◽  
Wilfried Roth ◽  
...  
Keyword(s):  
Cell Viability ◽  
Cell Lines ◽  
Penile Cancer ◽  
Multivariate Regression Analysis ◽  
Clinicopathological Characteristics ◽  
Akt Pathway ◽  
Akt Inhibitor ◽  
Free Survival ◽  
Kaplan Meier ◽  
Treatment Naïve

The PI3K/mTOR/AKT pathway might represent an intriguing option for treatment of penile cancer (PeCa). We aimed to assess whether members of this pathway might serve as biomarkers and targets for systemic therapy. Tissue of primary cancer from treatment-naïve PeCa patients was used for tissue microarray analysis. Immunohistochemical staining was performed with antibodies against AKT, pAKT, mTOR, pmTOR, pS6, pPRAS, p4EBP1, S6K1 and pp70S6K. Protein expression was correlated with clinicopathological characteristics as well as overall survival (OS), disease-specific survival (DSS), recurrence-free survival (RFS) and metastasis-free survival (MFS). AKT inhibition was tested in two primarily established, treatment-naïve PeCa cell lines by treatment with capivasertib and analysis of cell viability and chemotaxis. A total of 76 patients surgically treated for invasive PeCa were included. Higher expression of AKT was significantly more prevalent in high-grade tumors and predictive of DSS and OS in the Kaplan–Meier analysis, and an independent predictor of worse OS and DSS in the multivariate regression analysis. Treatment with pan-AKT inhibitor capivasertib in PeCa cell lines induced a significant downregulation of both total AKT and pAKT as well as decreased cell viability and chemotaxis. Selected protein candidates of the mTOR/AKT signaling pathway demonstrate association with histological and survival parameters of PeCa patients, whereas AKT appears to be the most promising one.

Sign in / Sign up

Export Citation Format

Share Document