scholarly journals miR-331-3p is involved in glucocorticoid resistance reversion by rapamycin through suppression of the MAPK signaling pathway

2020 ◽  
Vol 86 (3) ◽  
pp. 361-374
Author(s):  
Marianna Lucafò ◽  
Daria Sicari ◽  
Andrea Chicco ◽  
Debora Curci ◽  
Arianna Bellazzo ◽  
...  

Abstract Glucocorticoids (GCs) are commonly used as therapeutic agents for immune-mediated diseases and leukemia. However, considerable inter-individual differences in efficacy have been reported. Several reports indicate that the inhibitor of mTOR rapamycin can reverse GC resistance, but the molecular mechanism involved in this synergistic effect has not been fully defined. In this context, we explored the differential miRNA expression in a GC-resistant CCRF-CEM cell line after treatment with rapamycin alone or in co-treatment with methylprednisolone (MP). The expression analysis identified 70, 99 and 96 miRNAs that were differentially expressed after treatment with MP, rapamycin and their combination compared to non-treated controls, respectively. Two pathways were exclusively altered as a result of the co-treatment: the MAPK and ErbB pathways. We validated the only miRNA upregulated specifically by the co-treatment associated with the MAPK signaling, miR-331-3p. Looking for miR-331-3p targets, MAP2K7, an essential component of the JNK/MAPK pathway, was identified. Interestingly, MAP2K7 expression was downregulated during the co-treatment, causing a decrease in terms of JNK activity. miR-331-3p in mimic-transfected cells led to a significant decrease in MAP2K7 levels and promoted the reversion of GC resistance in vitro. Interestingly, miR-331-3p expression was also associated with GC-resistance in patient leukemia cells taken at diagnosis. The combination of rapamycin with MP restores GC effectiveness through the regulation of different miRNAs, suggesting the important role of these pharmacoepigenetic factors in GC response.

Author(s):  
Shan Lei ◽  
Zhiwei He ◽  
Tengxiang Chen ◽  
Xingjun Guo ◽  
Zhirui Zeng ◽  
...  

Abstract Background Accumulation evidence indicates the vital role of long non-coding RNAs (lncRNAs) in tumorigenesis and the progression of malignant tumors, including pancreatic cancer (PC). However, the role and the molecular mechanism of long non-coding RNA 00976 is unclear in pancreatic cancer. Methods In situ hybridization (ISH) and qRT-PCR was performed to investigate the association between linc00976 expression and the clinicopathological characteristics and prognosis of patients with PC. Subsequently, linc00976 over-expression vector and shRNAs were transfected into PC cells to up-regulate or down-regulate linc00976 expression. Loss- and gain-of function assays were performed to investigate the role of linc00976 in proliferation and metastasis in vitro and vivo. ITRAQ, bioinformatic analysis and rescue assay were used to illustrate the ceRNA mechanism network of linc00976/miR-137/OTUD7B and its downstream EGFR/MAPK signaling pathway. Results linc00976 expression was overexpressed in PC tissues and cell lines and was positively associated with poorer survival in patients with PC. Function studies revealed that linc00976 knockdown significantly suppressed cell proliferation, migration and invasion in vivo and in vitro, whereas its overexpression reversed these effects. Based on Itraq results and online database prediction, Ovarian tumor proteases OTUD7B was found as a downstream gene of linc00976, which deubiquitinated EGFR mediates MAPK signaling activation. Furthermore, Bioinformatics analysis and luciferase assays and rescue experiments revealed that linc00976/miR137/OTUD7B established the ceRNA network modulating PC cell proliferation and tumor growth. Conclusion The present study demonstrates that linc00976 enhances the proliferation and invasion ability of PC cells by upregulating OTUD7B expression, which was a target of miR-137. Ultimately, OTUD7B mediates EGFR and MAPK signaling pathway, suggesting that linc00976/miR-137/OTUD7B/EGFR axis may act as a potential biomarker and therapeutic target for PC.


2014 ◽  
Vol 28 (12) ◽  
pp. 1999-2011 ◽  
Author(s):  
Allyson Booth ◽  
Tammy Trudeau ◽  
Crystal Gomez ◽  
M. Scott Lucia ◽  
Arthur Gutierrez-Hartmann

The signaling pathways that govern the lactotrope-specific differentiated phenotype, and those that control lactotrope proliferation in both physiological and pathological lactotrope expansion, are poorly understood. Moreover, the specific role of MAPK signaling in lactotrope proliferation vs differentiation, whether activated phosphorylated MAPK is sufficient for prolactinoma tumor formation remain unknown. Given that oncogenic Ras mutations and persistently activated phosphorylated MAPK are found in human tumors, including prolactinomas and other pituitary tumors, a better understanding of the role of MAPK in lactotrope biology is required. Here we directly examined the role of persistent Ras/MAPK signaling in differentiation, proliferation, and tumorigenesis of rat pituitary somatolactotrope GH4 cells. We stimulated Ras/MAPK signaling in a persistent, long-term manner (over 6 d) in GH4 cells using two distinct approaches: 1) a doxycycline-inducible, oncogenic V12Ras expression system; and 2) continuous addition of exogenous epidermal growth factor. We find that long-term activation of the Ras/MAPK pathway over 6 days promotes differentiation of the bihormonal somatolactotrope GH4 precursor cell into a prolactin-secreting, lactotrope cell phenotype in vitro and in vivo with GH4 cell xenograft tumors. Furthermore, we show that persistent activation of the Ras/MAPK pathway not only fails to promote cell proliferation, but also diminishes tumorigenic characteristics in GH4 cells in vitro and in vivo. These data demonstrate that activated MAPK promotes differentiation and is not sufficient to drive tumorigenesis, suggesting that pituitary lactotrope tumor cells have the ability to evade the tumorigenic fate that is often associated with Ras/MAPK activation.


2019 ◽  
Vol 2019 ◽  
pp. 1-10 ◽  
Author(s):  
Fang-Fang Sun ◽  
Peng-Fei Hu ◽  
Yan Xiong ◽  
Jia-Peng Bao ◽  
Jing Qian ◽  
...  

Tricetin is a well-studied flavonoid with a wide range of pharmacological activities in cancer and inflammation. However, the ability of tricetin to ameliorate the inflammation that occurs in osteoarthritis (OA) has not been determined. This study explored the effects of tricetin on interleukin- (IL-) 1β-induced rat chondrocytes. Chondrocytes harvested from rat cartilage were incubated in vitro with tricetin in the presence of IL-1β. The expression of matrix metalloproteinase- (MMP-) 1, MMP-3, MMP-13, nitric oxide (NO), prostaglandin E2 (PGE2), Bax, and Bcl-2 was evaluated by real-time-PCR, ELISA, Griess reaction, and western blotting. Caspase-3 activity in chondrocytes was determined using a caspase-3 activity assay and MAPK pathway activity by western blotting. Tricetin decreased the expression of MMP-1, MMP-3, and MMP-13 at both the gene and protein level in IL-1β-induced rat chondrocytes. It also inhibited IL-1β-induced NO and PGE2 production, by modulating inducible NO synthase and cyclooxygenase 2 gene expression. An antiapoptotic role of tricetin involving the Bax/Bcl-2/caspase-3 pathway was also determined. The chondroprotective effect of tricetin was shown to be partly related to the suppression of the MAPK signaling pathway. The results of this study demonstrate the chondroprotective role of tricetin, based on its anticatabolic, anti-inflammatory, and antiapoptotic effects in chondrocytes. The therapeutic potential of tricetin in OA patients should be explored in future studies.


2021 ◽  
Author(s):  
Rui-Jun Bai ◽  
Di Liu ◽  
Yu-Sheng Li ◽  
Jian Tian ◽  
Deng-Jie Yu ◽  
...  

Abstract Background: To investigate whether OPN has an effect on autophagy in human osteoarthritic chondrocytes and determine the roles of CD44, αvβ3 integrin and the MAPK pathway in this progress. Methods: First, we cultured human OA chondrocytes in vitro and then treated cells with rhOPN to determine autophagy changes. Next , the anti-CD44 and anti-CD51/61 monoclonal antibodies (Abs) or isotype IgG were used to determine the possible role of CD44 and αvβ3 integrin; subsequently, an inhibitor of the ERK MAPK pathway was used to investigate the role of ERK MAPK. Western blotting was used to measure the beclin1, LC3 II and MAPK protein expression, and mRFP-GFP-LC3 confocal imaging was used to detect the autophagy levels. CCK-8 was used to assay the proliferation and activity of chondrocytes. Results: Our results showed that the LC3 protein was greatly decreased in OA cartilage compared to normal cartilage ,and OPN suppressed the autophagy activity in chondrocytes in vitro. Blocking experiments with anti-CD44 and anti-CD51/61 Abs indicated that OPN could suppress the expression of LC3II and beclin1 through αvβ3 integrin and CD44. Our results also indicated that the ratio of p-ERK/ ERK but not p-P38/P38 and p-JNK/JNK was increased after the rhOPN treatment. The ERK inhibitor inhibited the activity of OPN in the suppression of autophagy, and the CCK-8 results showed that rhOPN could promote chondrocyte proliferation. Conclusions: OPN inhibited chondrocyte autophagy through CD44 and αvβ3 integrin receptors and via the ERK MAPK signaling pathway.


Molecules ◽  
2020 ◽  
Vol 25 (9) ◽  
pp. 2248 ◽  
Author(s):  
Jian-Ming Chen ◽  
Pei-Yin Chen ◽  
Chia-Chieh Lin ◽  
Ming-Chang Hsieh ◽  
Jen-Tsun Lin

Background: Sesamin is a lignin present in sesame oil from the bark of Zanthoxylum spp. Sesamin reportedly has anticarcinogenic potential and exerts anti-inflammatory effects on several tumors. Hypothesis/Purpose: However, the effect of sesamin on metastatic progression in human head and neck squamous carcinoma (HNSCC) remains unknown in vitro and in vivo; hence, we investigated the effect of sesamin on HNSCC cells in vitro. Methods and Results: Sesamin-treated human oral cancer cell lines FaDu, HSC-3, and Ca9-22 were subjected to a wound-healing assay. Furthermore, Western blotting was performed to assess the effect of sesamin on the expression levels of matrix metalloproteinase (MMP)-2 and proteins of the MAPK signaling pathway, including p-ERK1/2, P-p38, and p-JNK1/2. In addition, we investigated the association between MMP-2 expression and the MAPK pathway in sesamin-treated oral cancer cells. Sesamin inhibited cell migration and invasion in FaDu, Ca9-22, and HSC-3 cells and suppressed MMP-2 at noncytotoxic concentrations (0 to 40 μM). Furthermore, sesamin significantly reduced p38 MAPK and JNK phosphorylation in a dose-dependent manner in FaDu and HSC-3 cells. Conclusions: These results indicate that sesamin suppresses the migration and invasion of HNSCC cells by regulating MMP-2 and is thus a potential antimetastatic agent for treating HNSCC.


2020 ◽  
Vol 134 (8) ◽  
pp. 1001-1025 ◽  
Author(s):  
Sonya Frazier ◽  
Martin W. McBride ◽  
Helen Mulvana ◽  
Delyth Graham

Abstract Placental microRNAs (miRNAs) regulate the placental transcriptome and play a pathological role in preeclampsia (PE), a hypertensive disorder of pregnancy. Three PE rodent model studies explored the role of placental miRNAs, miR-210, miR-126, and miR-148/152 respectively, by examining expression of the miRNAs, their inducers, and potential gene targets. This review evaluates the role of miR-210, miR-126, and miR-148/152 in PE by comparing findings from the three rodent model studies with in vitro studies, other animal models, and preeclamptic patients to provide comprehensive insight into genetic components and pathological processes in the placenta contributing to PE. The majority of studies demonstrate miR-210 is upregulated in PE in part driven by HIF-1α and NF-κBp50, stimulated by hypoxia and/or immune-mediated processes. Elevated miR-210 may contribute to PE via inhibiting anti-inflammatory Th2-cytokines. Studies report an up- and downregulation of miR-126, arguably reflecting differences in expression between cell types and its multifunctional capacity. MiR-126 may play a pro-angiogenic role by mediating the PI3K-Akt pathway. Most studies report miR-148/152 family members are upregulated in PE. Evidence suggests they may inhibit DNA methylation of genes involved in metabolic and inflammatory pathways. Given the genetic heterogeneity of PE, it is unlikely that a single placental miRNA is a suitable therapeutic target for all patients. Investigating miRNAs in PE subtypes in patients and animal models may represent a more appropriate approach going forward. Developing methods for targeting placental miRNAs and specific placental cell types remains crucial for research seeking to target placental miRNAs as a novel treatment for PE.


2020 ◽  
Author(s):  
Hongyu Zheng ◽  
Tingting Wang ◽  
Xiangmin Li ◽  
Wei He ◽  
Zhiqiang Gong ◽  
...  

Abstract Background: Intervertebral disc degeneration (IDD) is characterized by the loss of nucleus pulposus cells (NPCs) and phenotypic abnormalities. Accumulating evidence suggests that long noncoding RNAs (lncRNAs) are involved in the pathogenesis of IDD. In this study, we aimed to investigate the functional effects of lncRNA MALAT1 on NPCs in IDD and the possible mechanism governing these effects. Results: We validated the decreased expression of MALAT1 in the IDD tissues, which was associated with decreased Collagen II and Aggrecan expression. In vitro, overexpressed MALAT1 could attenuate the effect of IL-1β on NPC proliferation, apoptosis, and Aggrecan degradation. In vivo, MALAT1 overexpression attenuated the severity of disc degeneration in IDD model rats. Our molecular study further demonstrated that MALAT1 could sponge miR-503, modulate the expression of miR-503, and activate downstream MAPK signaling pathways. The effects of MALAT1 on NPCs were partially reversed/aggregated by miR-503 mimics/inhibitor treatment. Conclusion: Our data suggested that the MALAT1-miR-503-MAPK pathway plays a critical role in NPCs, which may be a potential strategy for alleviating IDD.


2012 ◽  
Vol 2012 ◽  
pp. 1-9 ◽  
Author(s):  
S. E. Hurst ◽  
S. C. Minkin ◽  
J. Biggerstaff ◽  
M. S. Dhar

Atp10cis a strong candidate gene for diet-induced obesity and type 2 diabetes. To identify molecular and cellular targets of ATP10C,Atp10cexpression was alteredin vitroin C2C12 skeletal muscle myotubes by transient transfection with anAtp10c-specific siRNA. Glucose uptake assays revealed that insulin stimulation caused a significant 2.54-fold decrease in 2-deoxyglucose uptake in transfected cells coupled with a significant upregulation of native mitogen-activated protein kinases (MAPKs), p38, and p44/42. Additionally, glucose transporter-1 (GLUT1) was significantly upregulated; no changes in glucose transporter-4 (GLUT4) expression were observed. The involvement of MAPKs was confirmed using the specific inhibitor SB203580, which downregulated the expression of native and phosphorylated MAPK proteins in transfected cells without any changes in insulin-stimulated glucose uptake. Results indicate thatAtp10cregulates glucose metabolism, at least in part via the MAPK pathway, and, thus, plays a significant role in the development of insulin resistance and type 2 diabetes.


2016 ◽  
Vol 39 (6) ◽  
pp. 2216-2226 ◽  
Author(s):  
Pei Li ◽  
Yuan Xu ◽  
Yibo Gan ◽  
Liyuan Wang ◽  
Bin Ouyang ◽  
...  

Background/Aims: Matrix homeostasis within the disc nucleus pulposus (NP) tissue is important for disc function. Increasing evidence indicates that sex hormone can influence the severity of disc degeneration. This study was aimed to study the role of 17β-estradiol (E2) in NP matrix synthesis and its underlying mechanism. Methods: Rat NP cells were cultured with (10-5, 10-7 and 10-9 M) or without (control) E2 for48 hours. The estrogen receptor (ER)-β antagonist PHTPP and ERβ agonist ERB 041 were used to investigate the role mediated by ERβ. The p38 MAPK inhibitor SB203580 was used to investigate the role of p38 MAPK signaling pathway. Gene and protein expression of SOX9, aggrecan and collagen II, glycosaminoglycan (GAG) content, and immunostaining assay for aggrecan and collagen II were analyzed to evaluate matrix production in rat NP cells. Results: E2 enhanced NP matrix synthesis in a concentration-dependent manner regarding gene and proetin expression of SOX9, aggrecan and collagen II, protein deposition of aggrecan and collagen II, and GAG content. Moreover, activation of p38 MAPK signaling pathway was increased with elevating E2 concentration. Further analysis indicated that ERB 041 and PHTPP could respectively enhance and suppress effects of E2 on matrix synthesis in NP cells, as well as activation of p38 MAPK pathway. Additionally, inhibition of p38 MAPK signaling pathway significantly abolished the effects of E2 on matrix synthesis. Conclusion: E2 can enhance matrix synthesis of NP cells and the ERβ/p38 MAPK pathway is involved in this regulatory process.


Author(s):  
Hongfang Wang ◽  
Jinlian Fu ◽  
Aiguo Wang

Obesity has become a global health problem. Research suggests that leptin, a hormone that responds to fat deposition, may be involved in mammalian reproduction; however, its precise role in embryo implantation is poorly understood. Here, primary porcine endometrium epithelium cells (PEECs) were cultured in vitro and used to evaluate the regulatory role of different leptin levels on β3-integrin, MMP9, HB-EGF, and IL-1β, which are, respectively, involved in four critical steps of embryo implantation. Results showed that only 0.01 nM leptin significantly improved β3-integrin mRNA expression (p < 0.05). MMP9 and HB-EGF mRNA expressions were upregulated by 0.10–10.00 nM leptin (p < 0.05). The IL-1β expression level was only increased by 10.00 nM leptin (p < 0.05). β3-integrin, MMP9, HB-EGF, and IL-1β mRNA and protein have a similar fluctuant response to increased leptin. Leptin’s influence on β3-integrin, MMP9, HB-EGF, and IL-1β disappeared when the JAK2, PI(3)K, or MAPK signaling pathways were blocked, respectively. In conclusion, leptin affected porcine implantation by regulating the expression of β3-integrin, MMP9, HB-EGF, and IL-1β in a dose-dependent manner. The signaling pathways of JAK2, PI(3)K, and MAPK may participate in this regulatory process. These findings will contribute to further understanding the mechanisms of reproductive disorders in obesity.


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