Activation Of JNK Signaling Pathway Research Articles

CGRP Promotes the Migration and Invasion of Human Tongue Squamous Cell Carcinoma Cells through Activation of JNK Signaling Pathway

CGRP Promotes the Migration and Invasion of Human Tongue Squamous Cell Carcinoma Cells through Activation of JNK Signaling Pathway

Emulsified isoflurane induces release of cytochrome C in human neuroblastoma SHSY-5Y cells via JNK (c-Jun N-terminal kinases) signaling pathway

A large number of studies have demonstrated that inhalation anesthetic isoflurane induced neural cell death by apoptosis in various cell and animal models. Emulsified isoflurane (EIso) is a new type of intravenous preparation of isoflurane that attracts increasing research attention as a promising clinical agent due to its both advantages as an intravenous and inhalation anesthetics medication. However, its safety and underlying molecular mechanism of neurotoxicity largely remain unknown. Therefore, it is meaningful to investigate the safety of EIso and to further elucidate its mechanism of anesthetic neurotoxicity.Human neuroblastoma SHSY-5Y cells were cultured, followed by a random exposure to one of three doses of EIso (0.56mmol/l, 1.12mmol/l, and 2.24mmol/l) or the corresponding intralipid as vehicle (0.3956μl/ml, 0.7912μl/ml and 1.5824μl/ml) for 6h, 12h or 24h. Cell viability was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5- diphenyl tetrazolium bromide (MTT) assay and the morphological changes were determined by a light microscope. We detect JNK, p-JNK and cytochrome C (cyto C) protein levels by western blotting. SP600125, a specific inhibitor of JNK, was used to detect the role of JNK pathway in the neurotoxicity of EIso.Our study showed that EIso reduced the viability of SHSY-5Y cells in a dose- and time-dependent manner. 0.56mmol/l EIso has no significant effects on cell viability, while 1.12mmol/l of EIso with 24-h and 2.24mmol/l of EIso with over 12-h exposure notably reduced cell viability. EIso dramatically increased the levels of p-JNK and cyto C. The JNK pathway inhibitor SP600125 significantly increased the cell viability of SHSY-5Y cells induced by EIso.These findings suggest that EIso induces damage in human neuroblastoma SHSY-5Y cells by JNK signaling pathway activation and cyto C release. SP600125 protects neural cells against EIso-induced injury. Our findings provide a new insight in the exploration of potential novel therapeutic strategies for the treatment of EIso-induced neurotoxicity and other neurodegenerative diseases.

Secretory Stanniocalcin 1 promotes metastasis of hepatocellular carcinoma through activation of JNK signaling pathway

The hypoxic microenvironment is well-characterized in hepatocellular carcinoma (HCC). Delineation of hypoxia-responsive events is an integral part to understand the pathogenesis of HCC. We studied the functional role and clinical relevance of Stanniocalcin 1 (STC1), a hypoxia-induced molecular target, in HCC. In our clinical cohort, STC1 transcript was up-regulated in HCC tumor tissues. Moreover, STC1 protein was detected in the sera of HCC patients. A higher serum STC1 level was correlated with larger tumor size and poorer 5-year disease-free survival. Functionally, recombinant STC1 protein (rhSTC1) promoted cell migration and cell invasion in vitro; and the effect was abolished by co-treatment of anti-STC1 neutralizing antibody. By in vivo mouse model, silencing of STC1 in HCC cells downregulated secretory STC1 level and suppressed lung metastasis. Furthermore, we found that rhSTC1 activated the JNK pathway, as evidenced by altered expression of the key molecular targets pJNK and p-c-Jun. The functional effects conferred by rhSTC1 were abrogated by co-treatment of JNK inhibitor. In summary, secretory STC1 enhances metastatic potential of HCC via JNK signaling. It potentially serves as a prognostic serum biomarker and a therapeutic target for HCC.

Exogenous hydrogen sulfide eliminates spatial memory retrieval impairment and hippocampal CA1 LTD enhancement caused by acute stress via promoting glutamate uptake

Acute stress impairs the hippocampus-dependent spatial memory retrieval, and its synaptic mechanisms are associated with hippocampal CA1 long-term depression (LTD) enhancement in the adult rats. Endogenous hydrogen sulfide (H2S) is recognized as a novel gasotransmitter and has the neural protective roles. However, very little attention has been paid to understanding the effects of H2S on spatial memory retrieval impairment. We observed the protective effects of NaHS (a donor of H2S) against spatial memory retrieval impairment caused by acute stress and its synaptic mechanisms. Our results showed that NaHS abolished spatial memory retrieval impairment and hippocampal CA1 LTD enhancement caused by acute stress, but not by glutamate transporter inhibitor l-trans-pyrrolidine-2,4-dicarboxylic (tPDC), indicating that the activation of glutamate transporters is necessary for exogenous H2S to exert its roles. Moreover, NaHS restored the decreased glutamate uptake in the hippocampal CA1 synaptosomal fraction caused by acute stress. Dithiothreitol (DTT, a disulfide reducing agent) abolished a decrease in the glutamate uptake caused by acute stress, and NaHS eradicated the decreased glutamate uptake caused by 5,5′-dithio-bis(2-nitrobenzoic)acid (DTNB, a thiol oxidizing agent), collectively, revealing that exogenous H2S increases glutamate uptake by reducing disulfide bonds of the glutamate transporters. Additionally, NaHS inhibited the increased expression level of phosphorylated c-Jun-N-terminal kinase (JNK) in the hippocampal CA1 region caused by acute stress. The JNK inhibitor SP600125 eliminated spatial memory retrieval impairment, hippocampal CA1 LTD enhancement and the decreased glutamate uptake caused by acute stress, indicating that exogenous H2S exerts these roles by inhibiting the activation of JNK signaling pathway.

Secreted phospholipase A2 of Clonorchis sinensis activates hepatic stellate cells through a pathway involving JNK signalling

BackgroundSecreted phospholipase A2 (sPLA2) is a protein secreted by Clonorchis sinensis and is a component of excretory and secretory products (CsESPs). Phospholipase A2 is well known for its role in liver fibrosis and inhibition of tumour cells. The JNK signalling pathway is involved in hepatic stellate cells (HSCs) activation. Blocking JNK activity with SP600125 inhibits HSCs activation. In a previous study, the protein CssPLA2 was expressed in insoluble inclusion bodies. Therefore, it’s necessary to express CssPLA2 in water-soluble form and determine whether the enzymatic activity of CssPLA2 or cell signalling pathways is involved in liver fibrosis caused by clonorchiasis.MethodsBalb/C mice were given an abdominal injection of MBP-CssPLA2. Liver sections with HE and Masson staining were observed to detect accumulation of collagen. Western blot of mouse liver was done to detect the activation of JNK signalling pathway. In vitro, HSCs were incubated with MBP-CssPLA2 to detect the activation of HSCs as well as the activation of JNK signalling pathway. The mutant of MBP-CssPLA2 without enzymatic activity was constructed and was also incubated with HSCs to check whether activation of the HSCs was related to the enzymatic activity of MBP-CssPLA2.ResultsThe recombinant protein MBP-CssPLA2 was expressed soluble and of good enzymatic activity. A mutant of CssPLA2, without enzymatic activity, was also constructed. In vivo liver sections of Balb/C mice that were given an abdominal injection of 50 μg/ml MBP-CssPLA2 showed an obvious accumulation of collagen and a clear band of P-JNK1 could be seen by western blot of the liver tissue. In vitro, MBP-CssPLA2, as well as the mutant, was incubated with HSCs and it was proved that activation of HSCs was related to activation of the JNK signalling pathway instead of the enzymatic activity of MBP-CssPLA2.ConclusionsActivation of HSCs by CssPLA2 is related to the activation of the JNK signalling pathway instead of the enzymatic activity of CssPLA2. This finding could provide a promising treatment strategy to interrupt the process of liver fibrosis caused by clonorchiasis.

NLRX1 accelerates cisplatin-induced ototoxity in HEI-OC1 cells via promoting generation of ROS and activation of JNK signaling pathway

Nucleotide-binding domain and leucine-rich-repeat-containing family member X1 (NLRX1), located in mitochondria, can recognize cytoplasmic pattern recognition receptors and is tightly related to reactive oxygen species (ROS) production, mitochondrial function, apoptosis and inflammation. The present study was designed to explore whether NLRX1 expresses in HEI-OC1 cells and, if so, to investigate the possible correlations between NLRX1 and cisplatin-induced ototoxity in vitro. Here, we report that NLRX1 was specifically localized to mitochondria in the cytoplasm of HEI-OC1 cells and its expression was increased concurrent with the increase of ROS production and occurrence of apoptosis in HEI-OC1 cells in response to cisplatin stimulus. NLRX1 overexpression led to a higher apoptosis in HEI-OC1 cells treated with cisplatin, whereas, NLRX silencing decreased cisplatin induced apoptosis. Mechanistic studies showed that NLRX1 activated mitochondrial apoptosis pathway as well as promoted ROS generation and JNK activation. Either inhibition of ROS generation or JNK signaling significantly prevented NLRX1-mediated mitochondrial apoptosis in HEI-OC1cells. In addition, NLRX1 expression was confirmed in cochlear explants. The findings from this work reveal that NLRX1 sensitizes HEI-OC1 cells to cisplatin-induced apoptosis via activation of ROS/JNK signaling pathway, suggesting that NLRX1 acts as an important regulator of the cisplatin-elicited ototoxity.

Dietary Flavonoids Luteolin and Quercetin Suppressed Cancer Stem Cell Properties and Metastatic Potential of Isolated Prostate Cancer Cells.

A highly invasive Du145-III subline was isolated by three successive passages of the parental Du145 prostate tumor cell line (Du145-P) through a Boyden chamber with matrigel-coated membrane support. Du145-III cells showed great invasion potential based on their increased ability to spread/migrate and enhanced expression/secretion of the matrix metalloproteinase 9 (MMP9). Du145-III cells exerted vasculogenic mimicry (VM) properties, reminiscent of endothelial cell characteristics and expressed elevated levels of cancer stem cell (CSC) markers, including Nanog, Sox2, CD44 and ABCG2 and ability to self-renew. Of prominence, MMP9 was required for the induction of VM and for increased stemness in Du145-III cells. Using Du145-III as a model, the effects of dietary flavonoids, luteolin and quercetin, were evaluated on stemness and invasion capacity of Du145-III cells in relation to JNK signaling pathway activation. These flavonoids depressed the malignancy of highly invasive Du145-III cells, VM, anchorage-independent spheroid formation and expression of certain CSC markers. Since luteolin and quercetin were able to target CSC cells and prevent cancer cell invasiveness, may serve as potential anti-angiogenesis and anti-metastasis agents.

Effect of curcumin pretreatment on JNK signaling pathway during one-lung ventilation-induced acute lung injury in mice

Objective To evaluate the effect of curcumin pretreatment on c-Jun N-terminal kinase(JNK)signaling pathway during one-lung ventilation(OLV)-induced acute lung injury in mice. Methods Ninety SPF male C57BL/6J mice, aged 6-9 weeks, weighing 18-24 g, were randomly divided into 6 groups(n=15 each)using a random number table: two-lung ventilation(TLV)group; OLV group; curcumin 100, 150, 200 and 250 mg/kg groups(C100, C150, C200 and C250 groups). The corresponding doses of curcumin were administered intraperitoneally at 2 h before one-lung ventilation in C100, C150, C200 and C250 groups.The animals were tracheally intubated and mechanically ventilated in volume-controlled mode.The ventilator settings were adjusted to maintain the end-tidal pressure of carbon dioxide at 35-45 mmHg.In OLV, C100, C150, C200 and C250 groups, unilateral lung was ventilated for 1.5 h followed by 0.5 h of TLV.Bilateral lungs were ventilated for 2.0 h in group TLV.Peak airway pressure and airway pressure were recorded at 1.5 h of OLV and 0.5 h of TLV.At the end of mechanical ventilation, left lungs were removed for microscopic examination of the pathologic changes, and the index of quantitative assessment for alveolar damage(IQA)was recorded.Wet/dry lung weight ratio(W/D ratio)was determined, and the cell apoptosis in lung tissues was detected using TUNEL.The apoptosis index(AI)was calculated.The expression of JNK mRNA was determined using real-time polymerase chain reaction.The expression of JNK and phosphorylated JNK was determined by Western blot.The phosphorylation of JNK was calculated. Results Compared with group TLV, the IQA, W/D ratio, AI, expression of JNK mRNA and phosphorylation of JNK were significantly increased in group OLV(P 0.05). Compared with group OLV, the pathological changes were significantly attenuated in sequence in C150, C200 and C250 groups. Conclusion The mechanism by which curcumin pretreatment reduces cell apoptosis during OLV-induced acute lung injury is related to inhibition of JNK signaling pathway activation in mice. Key words: Curcumin; JNK mitogen-activated protein kinases; Apoptosis; Respiratory distress syndrome, adult; Respiration, artificial

Oxymatrine Induces Liver Injury through JNK Signalling Pathway Mediated by TNF-α In Vivo.

Oxymatrine (OMT) is a traditional Chinese medicine monomer and has been used for the treatment of chronic viral hepatitis and many other diseases. We aimed to investigate whether OMT could induce hepatotoxicity in mice and explored the preliminary mechanisms of toxic effects. Twenty-four Institute for Cancer Research male mice were randomly divided into four groups: control group, 40, 160 and 320 mg/kg OMT-treated group. OMT was orally administered once daily for 7 days. The OMT-treated group exhibited an improved liver index and increase in serum alanine aminotransferase, aspartate aminotransferase and alkaline phosphatase,augmented liver histological injury, elevated levels of malondialdehyde and tumour necrosis factor alpha (TNF-α) accompanied by the activation of caspase-9/-8/-3, up-regulated expressions of tumour necrosis factor receptor l (TNFR1), TNF receptor-associated structure domain (TRADD) and phosphorylation of stress-activated protein kinase/c-jun N-terminal protein kinases (p-SAPK/JNK). Altogether, these results suggest that OMT at a dose of 320 mg/kg leads to liver damage and is related to the activation of JNK signalling pathway mediated by TNF-α in the liver of mice.

EF1A1/HSC70 Cooperatively Suppress Brain Endothelial Cell Apoptosis via Regulating JNK Activity.

In our previous study, eEF1A1 was identified to be a new target for protecting brain ischemia injury, but the mechanism remains largely unknown. In this study, we screened the downstream cellular protein molecules interacted with eEF1A1 and found mechanism of eEF1A1 in brain ischemia protection. Through co-immunoprecipitation and mass spectrometry for searching the interaction of proteins with eEF1A1 in bEnd3 cells, HSC70 was identified to be a binding protein of eEF1A1, which was further validated by Western blot and immunofluorescence. eEF1A1 or HSC70 knockdown, respectively, increased OGD-induced apoptosis of brain vascular endothelial cells, which was detected by Annexin V-FITC/PI staining. HSC70 or eEF1A1 knockdown enhances phosphorylated JNK, phosphorylation of c-JUN (Ser63, Ser73), cleaved caspase-9, and cleaved caspase-3 expression, which could be rescued by JNK inhibitor. In summary, our data suggest that the presence of chaperone forms of interaction between eEF1A1 and HSC70 in brain vascular endothelial cells, eEF1A1 and HSC70 can play a protective role in the process of ischemic stroke by inhibiting the JNK signaling pathway activation.

Inhibition of NF-κB promotes autophagy via JNK signaling pathway in porcine granulosa cells

The transcription factor nuclear factor-κB (NF-κB) plays an important role in diverse processes, including cell proliferation and differentiation, apoptosis and inflammation. However, the role of NF-κB in porcine follicle development is not clearly elucidated. In this study, we demonstrated that follicle stimulating hormone (FSH) increased the level of inhibitor of NF-κB (IκB) protein and promoted the cytoplasmic localization of p65, indicating that FSH inhibits the activation of NF-κB in porcine granulosa cells. Moreover, inhibition of NF-κB by FSH or another specific inhibitor of NF-κB, pyrrolidine dithiocarbamate (PDTC), could activate JNK signaling and enhance autophagic activity in porcine granulosa cells. Knockdown of RelA (p65) Subunit of NF-κB by RNA interference abrogated the activation of JNK signaling pathway and the increase of autophagic protein expression by FSH. Meanwhile, the functional significance of FSH or PDTC-mediated autophagy were further investigated. Our results demonstrated that the increased autophagy promoted progesterone secretion in porcine granulosa cells. Blockage of autophagy by chloroquine obviated the FSH or PDTC-induced progesterone production. Taken together, these results indicate that inhibition of NF-κB increased autophagy via JNK signaling, and promote steroidogenesis in porcine granulosa cells. Our results provide new insights into the regulation and function of autophagy in mammalian follicle development.

Role of JNK signaling pathway in dexmedetomidine-induced reduction of spinal neurotoxicity induced by lidocaine in rats

Objective To evaluate the role of C-Jun N-Terminal kinase(JNK)signaling pathway in dexmedetomidine-induced reduction of spinal neurotoxicity induced by lidocaine in rats. Methods Seventy-two adult male Sprague-Dawley rats, weighing 280–320 g, in which intrathecal catheters were successfully implanted without complications, were randomly divided into 6 groups(n=12 each)using a random number table: control group(group C); SP600125(JNK signaling pathway blocker)group(group SP); dexmedetomidine group(group D); lidocaine group(group L); dexmedetomidine+ lidocaine group(group DL); SP600125+ lidocaine group(group SPL). Dimethyl sulfoxide(DMSO)20 μl was injected intrathecally in group C. SP600125 30 μg and 10% lidocaine 20 μl were injected intrathecally in SP and L groups, respectively.At 20 min after intrathecal injection of 10% lidocaine, dexmedetomidine 75 μg/kg was injected intraperitoneally in group DL, and SP600125 30 μg was injected intrathecally in group SPL.Dexmedetomidine 75 μg/kg was injected intraperitoneally in group D. The mechanical paw withdrawal threshold(MWT)and thermal paw withdrawal latency(TWL)were measured before intrathecal catheters were implanted(T0), before intrathecal administration(T1), and at 4, 8 and 12 h and 1, 2, 3, 4, 5 and 6 days after intrathecal administration(T2-10). At 24 h after intrathecal administration, 6 rats randomly selected from each group were sacrificed.The lumbar segment(L4-5)of the spinal cord was removed for detection of cell apoptosis(by TUNEL)and phosphorylated JNK(p-JNK)expression(by Western blot). The apoptotic index was calculated. Results Compared with group C, no significant change was found in the MWT, TWL, apoptotic index and expression of p-JNK in SP and D groups(P>0.05), the MWT at T2-8 in group L, at T2-6 in group DL and at T2-5 in group SPL were significantly increased, the TWL at T2-8 in group L, at T2-5 in group DL and at T2-4 in group SPL were prolonged, and the apoptotic index and expression of p-JNK were increased in DL, SPL and L groups(P<0.05). Compared with group L, the MWT was significantly decreased, and the TWL was shortened at T2-8, and the apoptotic index and expression of p-JNK were decreased in DL and SPL groups(P<0.05). Conclusion The mechanism by which dexmedetomidine mitigates spinal neurotoxicity induced by lidocaine is related to inhibited activation of JNK signaling pathway in rats . Key words: JNK mitogen-activated prorein kinaese; Lidocaine; Dexmedetomidine; Spinal cord; Drug toxicity

Abstract 3946: Secretory ANXA3 endows liver cancer cells with tumorigenic and self-renewal abilities and promotes HCC development

Abstract Hepatocellular carcinoma (HCC) is the third leading cause of mortality in Southeast Asia and in Hong Kong. Despite advances in treatment, the prognosis of advanced HCC patients remains dismal. Contemporary challenge in treating HCC has been the common chemotherapy resistance and recurrence after therapy.Therefore, the identification of valid targets and the development of new therapies are urgently needed for more effective clinical management of this deadly disease. We found secretory annexin A3 (ANXA3) to be up-regulated in HCC cell lines, compared with immortalized normal liver cell line MIHA. Clinically, secretory ANXA3 levels in the serum were found to be progressively elevated from non-HCC individuals to early and advanced HCC patients, with up-regulation of serum ANXA3 to be tightly associated with gender, number of tumor nodules, tumor sizes and tumor stages. More importantly, the diagnostic value of secretory ANXA3, as evident by ROC analysis, was found to be more superior to the commonly used biomarker alpha-fetoprotein (AFP). Subsequent functional studies found secretory ANXA3 to promote cancer and stem cell-like properties of HCC cells. Co-culture of conditioned medium from ANXA3-overexpressing cells with ANXA3-absent HCC cells potentiated the abilities of HCC cells to migrate, invade, self-renew, induce tube formation in endothelial cells, and resist apoptosis induced by staurosporine and chemotherapy. The in vivo tumor-initiating capacity was also significantly enhanced in HCC cells when co-cultured with ANXA3-containing conditioned medium compared with conditioned medium from cells transfected with empty vector control. Similar functional properties were also observed when MIHA cells were treated with recombinant ANXA3 proteins. In an effort to characterize the molecular mechanism by which ANXA3 drives cancer and stem cell-like properties in HCC, cDNA microarray profiling was performed to compare the gene expression between ANXA3-depleted and control cells. Pathway enrichment analysis found many of the deregulated genes to be closely associated with the JNK/AP-1 signaling cascade. Activation of JNK pathway was detected when cells were treated with recombinant ANXA3 proteins or ANXA3-containing conditioned medium. Collectively, our findings suggest that secretory ANXA3 plays pivotal roles in promoting tumor initiation, growth and chemoresistance through the activation of JNK signaling pathway in HCC. Citation Format: Man Tong, Stephanie Ma. Secretory ANXA3 endows liver cancer cells with tumorigenic and self-renewal abilities and promotes HCC development. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3946. doi:10.1158/1538-7445.AM2015-3946

Ciclopirox induces autophagy through reactive oxygen species-mediated activation of JNK signaling pathway.

Ciclopirox olamine (CPX), a fungicide, has been demonstrated as a potential anticancer agent. However, the underlying anticancer mechanism is not well understood. Here, we found that CPX induced autophagy in human rhabdomyosarcoma (Rh30 and RD) cells. It appeared that CPX-induced autophagy was attributed to induction of reactive oxygen species (ROS), as N-acetyl-L-cysteine (NAC), a ROS scavenger and antioxidant, prevented this process. Furthermore, we observed that CPX induced activation of mitogen-activated protein kinases (MAPKs), including extracellular signal-regulated kinase 1/2 (ERK1/2), c-Jun N-terminal kinase (JNK) and p38 MAPK, which was also blocked by NAC. However, only inhibition of JNK (with SP600125) or expression of dominant negative c-Jun partially prevented CPX-induced autophagy, indicating that ROS-mediated activation of JNK signaling pathway contributed to CPX-induced autophagy. Of interest, inhibition of autophagy by chloroquine (CQ) enhanced CPX-induced cell death, indicating that CPX-induced autophagy plays a pro-survival role in human rhabdomyosarcoma cells. Our finding suggests that the combination with autophagy inhibitors may be a novel strategy in potentiating the anticancer activity of CPX for treatment of rhabdomyosarcoma.

Abstract 4225: Estrogen regulated oncogene SHON mediates the efficacy of anti-estrogen treatment in breast cancer

Abstract Background: Estrogen receptors (ER) play a pivotal role in the etiology and progression of breast cancer. Hormone receptor positive breast cancers usually respond to endocrine therapy at the beginning, but a substantial proportion will eventually develop anti-estrogen resistance. However, the mechanism remains largely unclear. Cross-talk between ER and growth factor signaling pathways is known to contribute to the development of anti-estrogen resistance. In addition, activation of JNK signaling pathway has been implicated in tamoxifen resistance of mammary carcinoma MCF-7 cells. We have demonstrated that SHON is a novel human oncogene and its expression is inducible by estradiol (E2). Moreover, SHON expression is highly positively correlated with ER, progesterone receptor (PR) and androgen receptor (AR) expression in breast cancer, and may also serve as a prognostic biomarker for predicting patient response to anti-estrogen therapy in ER+ breast cancer. Purpose: This study aimed to investigate how SHON modulated estrogen signaling and its role in anti-estrogen treatment and resistance in ER+ breast cancer. Methods: Estrogen responsive luciferase reporter assays were used to measure the activation of ER signaling by SHON. Total cell number and soft agar colony formation assays were used to determine the effects of SHON expression on the efficacy of anti-estrogens. Protein expression was measured by Western blotting. Results: Forced expression of SHON in MCF-7 cells increased ER transcriptional activity while depletion of endogenous SHON decreased this activity. Upon tamoxifen or fulvestrant treatment, MCF-7 cells stably transfected with SHON expression plasmid displayed an increase in total cell number and cell migration compared with the control vector transfected MCF-7 cells. Anti-estrogen treatment inhibited the colony formation of MCF-7 cells in soft agar, and this inhibitory effect was significantly abrogated by forced expression of SHON. SHON also increased the protein level of both ERα and JNK in MCF-7 cells under estrogen deprivation or stimulation, or under estrogen stimulation in combination with tamoxifen or fulvestrant treatment. Conclusion: There was a positive feedback of SHON and ERα expression. SHON may mediate the efficacy of anti-estrogen drugs via modulation of ERα and JNK expression. These results improve our understanding of the role of SHON in anti-estrogen treatment and provide evidence for the use of SHON antagonism in enhancing the efficacy of anti-estrogen treatment. Citation Format: Bing Xu, Yewon Jung, Jo Perry, Tao Zhu, Peter E. Lobie, Baiqu Huang, Jun Lu, Dong-Xu Liu. Estrogen regulated oncogene SHON mediates the efficacy of anti-estrogen treatment in breast cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4225. doi:10.1158/1538-7445.AM2014-4225

C-Jun N terminal kinase modulates NOX-4 derived ROS production and myofibroblasts differentiation in human breast stromal cells.

BackgroundHard consistency, developed under the influence of tumor cell factors, is a characteristic feature of a breast tumor. Activation of resident fibroblasts leading to a myofibroblast phenotype is the principal feature that orchestrates this fibrotic process. The aim of this study was to assess the effects induced by TGF-β1, a growth factor abundantly present in tumor microenvironment, on the molecular mechanisms that mediate myofibroblastic differentiation of normal human mammary fibroblasts.MethodsWe used an immortalized fibroblastic cell line derived from normal mammary tissue (RMF-EG cells) to study the effect of TGF-β1 in the expression of α-SMA and CTGF as markers of myofibroblastic differentiation. The influence of redox status and JNK activity on TGF-β1-induced transcriptional activity was measured by a luciferase reporter assay. We also used a shRNA approach to evaluate the influence of NOX4 in myofibroblastic differentiation.ResultsTGF-β1 stimulates the expression of myofibroblast markers α-SMA and CTGF. Using a NOX inhibitor (DPI) and cells expressing a shRNA for NOX4, we demonstrated that TGF-β1 promotes an oxidative environment that favors myofibroblastic differentiation. We also found that activation of c-Jun N-terminal kinase is required for TGF-β1-dependent expression of CTGF, NOX4 and α-SMA.ConclusionsHuman mammary stromal fibrosis, evaluated by the expression of early and late markers as CTGF and α-SMA, depends on the activation of JNK signaling pathway. Our results show that JNK activation is an early event that precedes the increase in ROS levels leading to myofibroblastic differentiation and tumor fibrosis, suggesting that inhibition of JNK may be used a method to interrupt the development of tumor desmoplasia.

Effect of sevoflurane preconditioning on autophagy after traumatic brain injury in rats: the role of JNK signaling pathway

Objective To investigate the effects of sevoflurane preconditioning on autophagy after traumatic brain injury (TBI) in rats and the role of C-Jun N-terminal kinase (JNK) signaling pathway.Methods Sixty adult male Sprague-Dawley rats,weighing 220-250 g,were randomly divided into 4 groups (n =15 each) using a random number table:sham operation group (group S),group TBI,TBI + sevoflurane preconditioning group (group TBI + Sevo) and TBI + sevoflurane preconditioning + JNK inhibitor SP600125 group (group TBI + Sev + SP).TBI models were established using Feeney' s method.In TBI + Sev and TBI + Sev + SP groups,the rats inhaled 2.4％ sevoflurane for 30 min once a day for 4 concecutive days,and TBI was produced at 24 h after the end of sevoflurane preconditioning.In TBI + Sev + SP group,SP600125 (6 mg/kg) was injected intrapetitoneally at 30 min after TBI.Five rats were chosen at day 1,3,and 7 after TBI,and neurological deficit score (NDS) was measured.The rats were then sacrificed and brains were removed to measure brain water content,expression of LC3 lⅡ and Beclin-1 mRNA (using PCR),and expression of LC3 Ⅱ,Beclin-1,JNK and phosphorylated JNK (p-JNK) (by Western blot).Results Compared with group S,brain water content and NDS were significantly increased,and the expression of LC3 Ⅱ and Beclin-1 protein and mRNA,JNK,and p-JNK was up-regulated in the other three groups.Brain water content and NDS were significantly decreased,and the expression of LC3 Ⅱ and Beclin-1 protein and mRNA,JNK,and p-JNK was down-regulated in TBI + Sev and TBI + Sev + SP groups as compared with group TBI,and in TBI + Sev + SP group as compared with TBI + Sev group.Conclusion The mechanism by which sevoflurane preconditioning mitigates TBI is related to inhibiton of activation of JNK signaling pathway and decreased autophagy in rats. Key words: Anesthetics, inhalation ; Craniocerebral trauma ; Autophagy ; Mitogen-activated protein kinases

Proteomics profiling of keratocystic odontogenic tumours reveals AIDA as novel biomarker candidate.

Keratocystic odontogenic tumour (KCOT) is a benign, yet aggressive odontogenic tumour. Herein, proteome analysis of KCOT lesions in comparison with control patient-matched tissue unaffected by the disease and with inflammatory odontogenic cysts, namely radicular cysts is presented. For the proteomics profiling, two complementary proteomics techniques MALDI-MS/MS and LC-ESI-MS/MS were employed. Potential candidate biomarkers were validated by immunohistochemistry. More than 43 proteins were found to be differentially expressed or up-regulated in KCOT lesions in comparison with patient-matched unaffected oral mucosa. These proteins bear important biological functions and are involved in cell proliferation, cytoskeletal re-organization, transcription, cellular motility and apoptosis. In particular, a number of differentially expressed proteins participate in autocrine regulation and signalization within JNK and p38 MAPK signalling pathways. Immunohistochemical validation of chosen putative biomarkers revealed axin interaction partner and dorsalization-antagonist (AIDA), known as a protein that blocks activation of JNK signalling pathway, as a differential biomarker for KCOT lesions on an independent cohort of KCOT tissue samples in comparison with most prevalent intra-oseal lesions inflammatory odontogenic cysts.

A novel herbal medicine, KIOM-C, induces autophagic and apoptotic cell death mediated by activation of JNK and reactive oxygen species in HT1080 human fibrosarcoma cells.

KIOM-C was recently demonstrated to have anti-metastatic activity in highly malignant cancer cells via suppression of NF-κB-mediated MMP-9 activity. In addition, it was reported to be effective for clearance of the influenza virus by increasing production of anti-viral cytokines, such as TNF-α and IFN-γ, and efficacious in the treatment of pigs suffering from porcine circovirus-associated disease (PCVAD). In this study, we investigated whether KIOM-C induces cancer cell death and elucidated the underlying anti-cancer mechanisms. In addition, we examined whether KIOM-C oral administration suppresses in vivo tumor growth of HT1080 cells in athymic nude mice. We initially found that KIOM-C at concentrations of 500 and 1000 µg/ml caused dose- and time-dependent cell death in cancer cells, but not normal hepatocytes, to approximately 50% of control levels. At the early stage of KIOM-C treatment (12 h), cells were arrested in G1 phase, which was accompanied by up-regulation of p21 and p27, down-regulation of cyclin D1, and subsequent increases in apoptotic and autophagic cells. Following KIOM-C treatment, the extent of caspase-3 activation, PARP cleavage, Beclin-1 expression, and LC3-II conversion was remarkably up-regulated, but p62 expression was down-regulated. Phosphorylation of AMPK, ULK, JNK, c-jun, and p53 was increased significantly in response to KIOM-C treatment. The levels of intracellular ROS and CHOP expression were also increased. In particular, the JNK-specific inhibitor SP600125 blocked KIOM-C-induced ROS generation and CHOP expression almost completely, which consequently almost completely rescued cell death, indicating that JNK activation plays a critical role in KIOM-C-induced cell death. Furthermore, daily oral administration of 85 and 170 mg/kg KIOM-C efficiently suppressed the tumorigenic growth of HT1080 cells, without systemic toxicity. These results collectively suggest that KIOM-C efficiently induces cancer cell death by both autophagy and apoptosis via activation of JNK signaling pathways, and KIOM-C represents a safe and potent herbal therapy for treating malignancies.

MiR-92a/DUSP10/JNK signalling axis promotes human pancreatic cancer cells proliferation

Pancreatic cancer is one of the most common types of cancers in the whole world with a poor prognosis. Finding out how the cancer form and develop is the most important way to cure this cancer. miRNAs, 21–22 nucleotides regulatory small non-coding RNAs, have been found to be critical involved in the growth of pancreatic cancer. In this study, we found that miR-92a was up regulated in three kinds of human pancreatic cancer cell lines. There is a correlation between miR-92a and malignant degree of human pancreatic cancer cell lines. Then we found that miR-92a was essential for promoting cell proliferation in human pancreatic cancer. Inhibition of the function of miR-92a repressed the proliferation of pancreatic cancer cells. Further, we found that miR-92a enhanced the activation of JNK signalling pathway by directly targeting the JNK signalling inhibitor DUSP10. DUSP10 is responsible for miR-92a induced JNK signalling and cell proliferation. Altogether, our study showed a miR-92a/DUSP10/JNK signalling pathway that plays an important role in regulating the proliferation of pancreatic cancer cells.