MAPK8

Gene Summary

Gene:MAPK8; mitogen-activated protein kinase 8
Aliases: JNK, JNK1, PRKM8, SAPK1, JNK-46, JNK1A2, SAPK1c, JNK21B1/2
Location:10q11.22
Summary:The protein encoded by this gene is a member of the MAP kinase family. MAP kinases act as an integration point for multiple biochemical signals, and are involved in a wide variety of cellular processes such as proliferation, differentiation, transcription regulation and development. This kinase is activated by various cell stimuli, and targets specific transcription factors, and thus mediates immediate-early gene expression in response to cell stimuli. The activation of this kinase by tumor-necrosis factor alpha (TNF-alpha) is found to be required for TNF-alpha induced apoptosis. This kinase is also involved in UV radiation induced apoptosis, which is thought to be related to cytochrom c-mediated cell death pathway. Studies of the mouse counterpart of this gene suggested that this kinase play a key role in T cell proliferation, apoptosis and differentiation. Several alternatively spliced transcript variants encoding distinct isoforms have been reported. [provided by RefSeq, Apr 2016]
Databases:VEGA, OMIM, HGNC, Ensembl, GeneCard, Gene
Protein:mitogen-activated protein kinase 8
Source:NCBIAccessed: 14 March, 2017

Ontology:

What does this gene/protein do?
Show (42)
Pathways:What pathways are this gene/protein implicaed in?
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Cancer Overview

Research Indicators

Publications Per Year (1992-2017)
Graph generated 14 March 2017 using data from PubMed using criteria.

Literature Analysis

Mouse over the terms for more detail; many indicate links which you can click for dedicated pages about the topic.

  • Xenograft Models
  • Transcription Factor AP-1
  • Signal Transduction
  • fms-Like Tyrosine Kinase 3
  • Neoplasms, Experimental
  • Lung Cancer
  • Mitogen-Activated Protein Kinase 3
  • Statistics as Topic
  • Messenger RNA
  • siRNA
  • Mitogen-Activated Protein Kinase 1
  • Reactive Oxygen Species
  • Mitogen-Activated Protein Kinase 8
  • Yeasts
  • X-Box Binding Protein 1
  • Phosphorylation
  • Mitogen-Activated Protein Kinase 9
  • Tissue Array Analysis
  • Western Blotting
  • Cell Movement
  • RNA Interference
  • Chromosome 10
  • Tumor Microenvironment
  • Cancer Gene Expression Regulation
  • Young Adult
  • Wound Healing
  • Apoptosis
  • MAP Kinase Signaling System
  • RTPCR
  • Wnt-5a Protein
  • Cell Proliferation
  • Transfection
  • Breast Cancer
  • Cell Cycle
  • Dose-Response Relationship, Drug
  • Xenopus laevis
  • Antineoplastic Agents
  • Mitogen-Activated Protein Kinases
  • Enzyme Activation
  • p21-Activated Kinases
  • Cell Survival
Tag cloud generated 14 March, 2017 using data from PubMed, MeSH and CancerIndex

Specific Cancers (2)

Data table showing topics related to specific cancers and associated disorders. Scope includes mutations and abnormal protein expression.

Note: list is not exhaustive. Number of papers are based on searches of PubMed (click on topic title for arbitrary criteria used).

Latest Publications: MAPK8 (cancer-related)

Feng J, Yan PF, Zhao HY, et al.
Inhibitor of Nicotinamide Phosphoribosyltransferase Sensitizes Glioblastoma Cells to Temozolomide via Activating ROS/JNK Signaling Pathway.
Biomed Res Int. 2016; 2016:1450843 [PubMed] Free Access to Full Article Related Publications
Overcoming temozolomide (TMZ) resistance is a great challenge in glioblastoma (GBM) treatment. Nicotinamide phosphoribosyltransferase (NAMPT) is a rate-limiting enzyme in the biosynthesis of nicotinamide adenine dinucleotide and has a crucial role in cancer cell metabolism. In this study, we investigated whether FK866 and CHS828, two specific NAMPT inhibitors, could sensitize GBM cells to TMZ. Low doses of FK866 and CHS828 (5 nM and 10 nM, resp.) alone did not significantly decrease cell viability in U251-MG and T98 GBM cells. However, they significantly increased the antitumor action of TMZ in these cells. In U251-MG cells, administration of NAMPT inhibitors increased the TMZ (100 μM)-induced apoptosis and LDH release from GBM cells. NAMPT inhibitors remarkably enhanced the activities of caspase-1, caspase-3, and caspase-9. Moreover, NAMPT inhibitors increased reactive oxygen species (ROS) production and superoxide anion level but reduced the SOD activity and total antioxidative capacity in GBM cells. Treatment of NAMPT inhibitors increased phosphorylation of c-Jun and JNK. Administration of JNK inhibitor SP600125 or ROS scavenger tocopherol with TMZ and NAMPT inhibitors substantially attenuated the sensitization of NAMPT inhibitor on TMZ antitumor action. Our data indicate a potential value of NAMPT inhibitors in combined use with TMZ for GBM treatment.

Liu L, Xu Y, Reiter RJ, et al.
Inhibition of ERK1/2 Signaling Pathway is Involved in Melatonin's Antiproliferative Effect on Human MG-63 Osteosarcoma Cells.
Cell Physiol Biochem. 2016; 39(6):2297-2307 [PubMed] Related Publications
BACKGROUND: In a previous study, we found that melatonin inhibits MG-63 osteosarcoma cell proliferation; however, the underlying mechanisms remain elusive. Mitogen-activated protein kinase (MAPK) and Akt signaling pathways play key roles in the anticancer effects of melatonin.
AIMS: The present study investigated whether MAPK and Akt signaling pathways are involved in melatonin's antiproliferative actions on the human MG-63 osteosarcoma cells.
METHODS/RESULTS: Western blot analysis confirmed that melatonin significantly inhibited phosphorylation of ERK1/2 but not p38, JNK, or Akt. The expression of ERK1/2, p38, JNK, and Akt was not altered by melatonin. PD98059 and melatonin alone, and especially in combination, significantly inhibited cell proliferation. The changes included G1 and G2/M phase arrest of the cell cycle, and a downregulation of the expression at both the protein and mRNA levels of cyclin D1 and CDK4 (related to the G1 phase) and of cyclin B1 and CDK1 (related to the G2/M phase) as measured by flow cytometry after propidium iodide staining, and both western blot and real-time PCR, respectively. Furthermore, the combination of PD98059 and melatonin synergistically and markedly augmented the action of either agent alone. Co-immunoprecipitation further confirmed that there was an interaction between p-ERK1/2 and cyclin D1, CDK4, cyclin B1, or CDK1, which was blunted in the presence of melatonin or PD98059.
CONCLUSION: These findings suggest that melatonin's antiproliferative action is mediated by inhibition of the ERK1/2 signaling pathway rather than the p38, JNK, or Akt pathways.

Hsia TC, Yu CC, Hsiao YT, et al.
Cantharidin Impairs Cell Migration and Invasion of Human Lung Cancer NCI-H460 Cells via UPA and MAPK Signaling Pathways.
Anticancer Res. 2016; 36(11):5989-5997 [PubMed] Related Publications
Cantharidin (CTD), a component of natural mylabris (Mylabris phalerata Pallas), has been shown to have biological activities and induce cell death in many human cancer cells. In the present study, we investigated the effect of CTD on cell migration and invasion of NCI-H460 human lung cancer cells. Cell viability was examined and results indicated that CTD decreased the percentage of viable cells in dose-dependent manners. CTD inhibited cell migration and invasion in dose-dependent manners. Gelatin zymography analysis was used to measure the activities of matrix metalloproteinases (MMP-2/-9) and the results indicated that CTD inhibited the enzymatic activities of MMP-2/-9 of NCI-H460 cells. Western blotting was used to examine the protein expression of NCI-H460 cells after incubation with CTD and the results showed that CTD decreased the expression of MMP-2/-9, focal adhesion kinase (FAK), Ras homolog gene family, member A (Rho A), phospho-protein kinase B (AKT) (Thr308)(p-AKT(308)), phospho-extracellular signal-regulated kinase1/2 (p-ERK1/2), phospho-p38 mitogen-activated protein (MAP) kinase (p-p38), phospho c-Jun N-terminal kinase 1/2 (p-JNK1/2), nuclear factor-κB (NF-κB) and urokinase plasminogen activator (UPA). Furthermore, confocal laser microscopy was used to confirm that CTD suppressed the expression of NF-κB p65, but did not significantly affect protein kinase C (PKC) translocation in NCI-H460 cells. Based on those observations, we suggest that CTD may be used as a novel anticancer metastasis agent for lung cancer in the future.

Vesely DL
Heart Peptide Hormones: Adjunct and Primary Treatments of Cancer.
Anticancer Res. 2016; 36(11):5693-5700 [PubMed] Related Publications
Four heart hormones, namely atrial natriuretic peptide (ANP), long-acting natriuretic peptide (LANP), vessel dilator and kaliuretic peptide reduce up to 97% of cancer cells in vitro. These four cardiac hormones eliminate up to 80% of human pancreatic adenocarcinomas, two-thirds of human breast carcinomas and up to 86% of human small-cell lung carcinomas growing in athymic mice. ANP given intravenously for 3 hours after 'curative' lung surgery as an adjunct to surgery results in a 2-year relapse-free survival of 91% compared to 75% for those treated with surgery alone. The anticancer mechanisms of action of these peptides involve binding to receptors on the cancer cells, followed by 95% inhibition of the conversion of inactive to active rat sarcoma-bound guanosine triphosphate (RAS)-mitogen-activated protein kinase (MAPK) kinases 1/2 (MEK 1/2) (98% inhibition)-extracellular signal-related kinases 1/2 (ERK1/2) (96% inhibition) cascade in cancer cells. They are dual inhibitors of vascular endothelial growth factor (VEGF) and its VEGF2 receptor (up to 89%). They also inhibit MAPK9, i.e. c-JUN-N-terminal kinase 2. One of the downstream targets of VEGF is β-catenin, which these peptides inhibit by up to 88%. These four peptide hormones inhibit the Wingless-related integration site (WNT) pathway 68% and WNT secreted-Frizzled protein is reduced by up to 84%. Signal transducer and activator of transcription 3 (STAT3), a final 'switch' that activates gene expression that leads to malignancy, is specifically reduced up to 88% by these peptides but they do not affect STAT1. There is crosstalk between the RAS-MEK 1/2-ERK 1/2 kinase cascade, VEGF, β-catenin, JNK, WNT, and STAT pathways and each of these pathways and their crosstalk is inhibited by these peptide hormones. They enter the nucleus of cancer cells where they inhibit the proto-oncogenes c-FOS (by up to 82%) and c-JUN (by up to 61%).
CONCLUSION: These multiple kinase inhibitors have both adjunct and primary anticancer effects.

Roh T, Kim SW, Moon SH, Nam MJ
Genistein induces apoptosis by down-regulating thioredoxin-1 in human hepatocellular carcinoma SNU-449 cells.
Food Chem Toxicol. 2016; 97:127-134 [PubMed] Related Publications
Genistein (GEN), a natural isoflavonoid phytoestrogen, has anti-cancer activity against various types of cancers. However, GEN has not been thoroughly investigated in human hepatocellular carcinoma cells. In this study, we evaluated the anti-cancer effects of GEN on SNU-449 cells. GEN inhibited the proliferation of SNU-449 cells in a concentration-dependent manner. We observed the typical characteristics of apoptosis, such as DNA fragmentation and caspase-3 activation. To identify proteins related to GEN-induced apoptosis, we performed two-dimensional electrophoresis and identified differentially expressed proteins. Proteomic analysis showed that the antioxidant protein thioredoxin-1 was associated with GEN-induced apoptosis. GEN treatment decreased thioredoxin-1 levels and increased intracellular accumulation of reactive oxygen species. In addition, GEN activated apoptosis signal-regulating kinase 1, c-Jun N-terminal kinases (JNK) and p38. We also observed that pretreatment with the JNK and p38 inhibitors (SP600125 and SB203580) decreased GEN-induced cell death. These results indicate that GEN has potential antitumor effects against SNU-449 cells through the down-regulation of thioredoxin-1.

Shen KH, Li CF, Chien LH, et al.
Role of galectin-1 in urinary bladder urothelial carcinoma cell invasion through the JNK pathway.
Cancer Sci. 2016; 107(10):1390-1398 [PubMed] Free Access to Full Article Related Publications
Human galectin-1 is a member of the galectin family, proteins with conserved carbohydrate-recognition domains that bind galactoside. Galectin-1 is highly expressed in various tumors and participates in various oncogenic processes. However, detailed descriptions of the function of galectin-1 in urinary bladder urothelial carcinoma have not been reported. Our previous cohort investigation showed that galectin-1 is associated with tumor invasiveness and is a possible independent prognostic marker of urinary bladder urothelial carcinoma. The present study aimed to clarify the relevance of galectin-1 expression level to tumor progression and invasion. In order to decipher a mechanism for the contribution of galectin-1 to the malignant behavior of urinary bladder urothelial carcinoma, two bladder cancer cell lines (T24 and J82) were established with knockdown of galectin-1 expression by shRNA. Bladder cancer cells with LGALS1 gene silencing showed reduced cell proliferation, lower invasive capability, and lower clonogenicity. Extensive signaling pathway studies indicated that galectin-1 participated in bladder cancer cell invasion by mediating the activity of MMP9 through the Ras-Rac1-MEKK4-JNK-AP1 signaling pathway. Our functional analyses of galectin-1 in urinary bladder urothelial carcinoma provided novel insights into the critical role of galectin-1 in tumor progression and invasion. These results revealed that silencing the galectin-1-mediated MAPK signaling pathway presented a novel strategy for bladder cancer therapy.

Wei H, Wang N, Zhang Y, et al.
Wnt-11 overexpression promoting the invasion of cervical cancer cells.
Tumour Biol. 2016; 37(9):11789-11798 [PubMed] Related Publications
Wnt-11 is a positive regulator of the Wnt signaling pathway, which plays a crucial role in carcinogenesis. However, Wnt-11 expression in cervical cancer has not been well investigated. The aim of this study was to investigate the role of Wnt-11 in cervical tumor proliferation and invasion. This study examined 24 normal cervical squamous epithelia, 29 cervical intraepithelial neoplasia (CIN), and 78 cervical cancer samples. The expression of Wnt-11 was investigated by immunohistochemistry and quantitative reverse transcription-polymerase chain reaction analysis. The expression of the high-risk human papilloma virus (HR-HPV) E6 oncoprotein was also investigated by immunohistochemistry. In addition, the expression of Wnt-11, HR-HPV E6, JNK-1, phosphorylated JNK-1(P-JNK1), and β-catenin was examined by western blot analysis following Wnt-11 knockdown or overexpression in HeLa or SiHa cells, respectively. The promotion of cervical cancer cell proliferation and invasion was investigated using the cell counting kit-8 and Matrigel invasion assay, respectively. Wnt-11 and HR-HPV E6 expression increased in a manner that corresponded with the progression of cervical cancer and was significantly correlated with the International Federation of Gynecology and Obstetrics cancer stage, lymph node metastasis, tumor size, and HPV infection. Wnt-11 protein expression was positively associated with HR-HPV E6 protein expression in all 78 cervical cancer samples (P < 0.001). Furthermore, Wnt-11 was positively associated with P-JNK1 expression and promoted cervical cancer cell proliferation and invasion. These observations suggest that the increased Wnt-11 expression observed in cervical cancer cells may lead to the phosphorylation and activation of JNK-1 and significantly promote tumor cell proliferation and cell migration/invasion through activation of the Wnt/JNK pathway. Consequently, Wnt-11 may serve as a novel target for cervical cancer therapy.

Li W, Wu J, Li Z, et al.
Melatonin induces cell apoptosis in Mia PaCa-2 cells via the suppression of nuclear factor-κB and activation of ERK and JNK: A novel therapeutic implication for pancreatic cancer.
Oncol Rep. 2016; 36(5):2861-2867 [PubMed] Related Publications
Melatonin is synthesized by the pineal gland and is released into the blood. In the last several years, some studies have shown that melatonin has anticancer properties; however, the mechanisms behind the antitumour traits are unclear, especially in pancreatic cancer. Therefore, in the present study, we investigated the antitumour effects of melatonin on the human pancreatic carcinoma cell line MIA PaCa‑2 and explored its biological mechanisms. MIA PaCa‑2 cells were treated with melatonin, and we used a CCK‑8 assay to evaluate the cell viability. We also used flow cytometry to observe cell apoptosis and western blot analysis to assess the protein expression. Our study found that melatonin inhibited cell viability, suppressed colony formation and reduced cell migration and invasion and induced cell apoptosis in MIA PaCa‑2 cells. Our results showed that melatonin treatment inhibited NF‑κB p65 activation. Moreover, melatonin treatment activated the mitogen‑activated protein kinase pathways (c‑jun N‑terminal kinase and extracellular‑regulated kinase 1/2), which increased Bax protein expression and caspase‑3 cleavage and decreased Bcl‑2 protein expression. These new developments demonstrate that melatonin plays a potential role in anticancer treatment and may act as an effective therapeutic agent in the future.

Wang P, Ye JA, Hou CX, et al.
Combination of lentivirus-mediated silencing of PPM1D and temozolomide chemotherapy eradicates malignant glioma through cell apoptosis and cell cycle arrest.
Oncol Rep. 2016; 36(5):2544-2552 [PubMed] Free Access to Full Article Related Publications
Temozolomide (TMZ) is approved for use as first-line treatment for glioblastoma multiforme (GBM). However, GBM shows chemoresistance shortly after the initiation of treatment. In order to detect whether silencing of human protein phosphatase 1D magnesium dependent (PPM1D) gene could increase the effects of TMZ in glioma cells, glioma cells U87-MG were infected with lentiviral shRNA vector targeting PPM1D silencing. After PPM1D silencing was established, cells were treated with TMZ. The multiple functions of human glioma cells after PPM1D silencing and TMZ chemotherapy were detected by flow cytometry and MTT assay. Significantly differentially expressed genes were distinguished by microarray-based gene expression profiling and analyzed by gene pathway enrichment analysis and ontology assessment. Western blotting was used to establish the protein expression of the core genes. PPM1D gene silencing improves TMZ induced cell proliferation and induces cell apoptosis and cell cycle arrest. When PPM1D gene silencing combined with TMZ was performed in glioma cells, 367 genes were upregulated and 444 genes were downregulated compared with negative control. The most significant differential expression pathway was pathway in cancer and IGFR1R, PIK3R1, MAPK8 and EP300 are core genes in the network. Western blotting showed that MAPK8 and PIK3R1 protein expression levels were upregulated and RB1 protein expression was decreased. It was consistent with that detected in gene expression profiling. In conclusion, PPM1D gene silencing combined with TMZ eradicates glioma cells through cell apoptosis and cell cycle arrest. PIK3R1/AKT pathway plays a role in the multiple functions of glioma cells after PPM1D silencing and TMZ chemotherapy.

Chen GY, Shu YC, Chuang DY, Wang YC
Inflammatory and Apoptotic Regulatory Activity of Tanshinone IIA in Helicobacter pylori-Infected Cells.
Am J Chin Med. 2016; 44(6):1187-1206 [PubMed] Related Publications
Helicobacter pylori infections induce host cell inflammation and apoptosis, however, they are conflicting. Tanshinone IIA is an active compound of Salvia miltiorrhiza Bge. In this study, we investigated the regulatory effects of tanshinone IIA on H. pylori-induced inflammation and apoptosis in vitro. Tanshinone IIA treatments (13.6-54.4[Formula: see text][Formula: see text]M) significantly decreased nuclear factor kappa B (NF-kB) and mitogen-activated protein kinase (MAPK) [p-38 and C-terminal Jun-kinase 1/2 (JNK1/2)] protein expressions and inflammatory substance [cyclooxygenase-2 (COX-2), 5-lipooxygenase (5-LOX), intercellular adhesion molecule-1 (ICAM-1), reactive oxygen species (ROS), nitric oxide (NO), inducible nitric oxide synthase (iNOS), interleukin-1[Formula: see text] (IL-1[Formula: see text], IL-6, and IL-8] production in the H. pylori-infected cells. In contrast, tanshinone IIA treatments significantly increased apoptotic relevant protein [Bcl-2-associated X protein (Bax) and caspase 9] expressions and increased mitochondrial transmembrane potential ([Formula: see text] disruption, mitochondrial cytochrome [Formula: see text] (cyt [Formula: see text] release, and caspase cascades. Tanshinone IIA treatments effectively decreased H. pylori-induced inflammation and significantly promoted H. pylori-induced intrinsic apoptosis through NF-kB and MAPK (p-38 and JNK) pathways. Tanshinone IIA has great potential as a candidate to protect host cells from H. pylori-induced severe inflammation and gastric cancer.

Liu R, Wang G, Liu C, et al.
Gene expression profile analysis of dbpA knockdown in colorectal cancer cells.
Cell Biol Int. 2016; 40(12):1280-1293 [PubMed] Related Publications
DNA-binding protein A (dbpA) has been reported associated with the pathogenesis and development of various cancers. However, no evidence showed the gene expression profiling alternation involved in dbpA knockdown in colorectal cancer (CRC) cells. Small interference RNA (siRNA) method was used to knock down dbpA expression in SW620 cells. The changes of gene expression profiles in dbpA knockdown SW620 cells were determined by microarray analysis and Western blot. A total of 578 genes expressed differentially (twofold change), 181 genes were up-regulated, and 397 down-regulated in the dbpA knockdown group in comparison with the control group. The discrimination reliability was further verified by principal component analysis and Pearson correlation. Gene ontology (GO) pathway analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis showed that the most significantly expressed genes were linked to MAPK signaling pathway. Furthermore, Western blot verified that dbpA knockdown directly inhibited the activations of TAK1, p38, and JNK in CRC cells. In conclusion, dbpA knockdown in SW620 cells altered the expression of carcinogenesis-associated genes in CRC and the involvement of dbpA on CRC might through MAPK signaling pathway, which might provide valuable evidence to further investigate the correlation between dbpA expression and CRC development.

Luo F, Shi J, Shi Q, et al.
Mitogen-Activated Protein Kinases and Hypoxic/Ischemic Nephropathy.
Cell Physiol Biochem. 2016; 39(3):1051-67 [PubMed] Related Publications
Tissue hypoxia/ischemia is a pathological feature of many human disorders including stroke, myocardial infarction, hypoxic/ischemic nephropathy, as well as cancer. In the kidney, the combination of limited oxygen supply to the tissues and high oxygen demand is considered the main reason for the susceptibility of the kidney to hypoxic/ischemic injury. In recent years, increasing evidence has indicated that a reduction in renal oxygen tension/blood supply plays an important role in acute kidney injury, chronic kidney disease, and renal tumorigenesis. However, the underlying signaling mechanisms, whereby hypoxia alters cellular behaviors, remain poorly understood. Mitogen-activated protein kinases (MAPKs) are key signal-transducing enzymes activated by a wide range of extracellular stimuli, including hypoxia/ischemia. There are four major family members of MAPKs: the extracellular signal-regulated kinases-1 and -2 (ERK1/2), the c-Jun N-terminal kinases (JNK), p38 MAPKs, and extracellular signal-regulated kinase-5 (ERK5/BMK1). Recent studies, including ours, suggest that these MAPKs are differentially involved in renal responses to hypoxic/ischemic stress. This review will discuss their changes in hypoxic/ischemic pathophysiology with acute kidney injury, chronic kidney diseases and renal carcinoma.

Lee SI, Bae JA, Ko YS, et al.
Geijigajakyak decoction inhibits the motility and tumorigenesis of colorectal cancer cells.
BMC Complement Altern Med. 2016; 16(1):288 [PubMed] Free Access to Full Article Related Publications
BACKGROUND: Recent studies report that inflammatory diseases of the large intestine are associated with colorectal cancer. Geijigajakyak Decoction (GJD) has antispasmodic and anti-inflammatory effects on the gastrointestinal tract. Thus, in light of the connection between chronic bowel inflammation and colorectal cancer (CRC), we asked whether GJD inhibits colorectal tumorigenesis.
METHODS: The effects of GJD on the viability and proliferation of CRC cells were evaluated using MTT and BrdU assays, respectively. The motility of CRC cells was examined by a Transwell migration/invasion assay and immunoblot analysis was used to examine the signaling pathways associated with migration. A syngeneic Balb/c mice allograft model, in which CT26 cells were injected into the dorsum, was used to evaluate the anti-tumor effects of GJD in vivo.
RESULTS: GJD had no cytotoxic effects against HCT116 CRC cells, although it did inhibit their proliferation. GJD inhibited the migration of HCT116 cells, and suppressed the invasion of HCT116, Caco2, and CSC221 CRC cells. In addition, GJD downregulated the expression of p-JNK and p-p38 MAPK, which are downstream signaling molecules associated with invasiveness. Furthermore, oral administration of GJD (333 mg/kg, twice a day) inhibited tumor growth in a mouse xenograft model.
CONCLUSIONS: GJD inhibited the motility of human CRC cells and suppressed tumorigenesis in a mouse model. These results suggest that GJD warrants further study as a potential adjuvant anti-cancer therapy.

Wang K, Zhu X, Zhang K, et al.
FoxM1 inhibition enhances chemosensitivity of docetaxel-resistant A549 cells to docetaxel via activation of JNK/mitochondrial pathway.
Acta Biochim Biophys Sin (Shanghai). 2016; 48(9):804-9 [PubMed] Related Publications
Docetaxel is recommended as a second-line chemotherapy agent for the non-small-cell lung cancer (NSCLC); however, drug resistance greatly limits its efficiency. Forkhead box M1 (FoxM1), an oncogenic transcription factor, is believed to be involved in the chemoresistance of various human cancers; whereas the association of FoxM1 with acquired docetaxel-resistance in NSCLC remains unclear. In the present study, we investigated the involvement of FoxM1 in the docetaxel-resistant human lung adenocarcinoma A549 cells (A549/DTX). Our results showed that FoxM1 expression was significantly increased in the A549/DTX cells compared with that in the parental A549 cells. FoxM1 siRNA silencing promoted the cytotoxic and pro-apoptotic effect of docetaxel in A549/DTX cells, which was possibly mediated through inducing the activation of c-Jun N-terminal kinases/mitochondrial signaling pathway. Our results suggest a critical role of FoxM1 in docetaxel-resistance of the A549 cells and form the basis for the development of combined therapy of docetaxel and FoxM1 depletion in treating NSCLC.

Koushyar S, Grant GH, Uysal-Onganer P
The interaction of Wnt-11 and signalling cascades in prostate cancer.
Tumour Biol. 2016; 37(10):13049-13057 [PubMed] Related Publications
Prostate cancer (PCa) is the second most common cancer among the male population. Conventional therapies target androgen signalling, which drives tumour growth; however, they provide limited survival benefits for patients. It is essential, therefore, to develop a more specific biomarker than the current gold standard, PSA testing. The Wnt signalling pathway induces expression of target genes through cell surface receptors. A non-canonical member of this family, Wnt-11, is evolutionarily highly conserved and is normally expressed by various cells in the developing embryo, as well as in the heart, liver and skeletal muscle of adult humans. We comprehensively review several cell signalling pathways to explain how they interact with Wnt-11, demonstrating its use as a potential biomarker for PCa. Several studies have shown that the expression of Wnt-11 is associated with gastric, renal and colorectal adenocarcinomas and PCa. Moreover, Wnt-11 affects extracellular matrix composition and cytoskeletal rearrangement, and it is required for proliferation and/or survival during cell differentiation. It was found that PCa cell lines express high levels of Wnt-11, which allows differentiation of the epithelial prostate tumour cells to neuron-like (NE) cells. The NE cells produce additional factors that can cause regression after treatment. Accumulating evidence shows that Wnt-11 could be a potential biomarker in diagnosing PCa. Many studies have shown both non-canonical and canonical Wnts interact with several signalling cascades such as PKC, JNK, NF-κB, Rho, PKA and PI3K. In particular, evidence demonstrates Wnt-11 is involved in the progression of PCa, thus it could have the potential to become both a specific disease marker and an important therapeutic target.

Demiroglu-Zergeroglu A, Ergene E, Ayvali N, et al.
Quercetin and Cisplatin combined treatment altered cell cycle and mitogen activated protein kinase expressions in malignant mesotelioma cells.
BMC Complement Altern Med. 2016; 16(1):281 [PubMed] Free Access to Full Article Related Publications
BACKGROUND: Malignant mesothelioma is a locally aggressive and highly lethal neoplasm of pleural, peritoneal and pericardial mesothelial cells without successful therapy. Previously, we reported that Quercetin in combination with Cisplatin inhibits cell proliferation and activates caspase-9 and -3 enzymes in different malignant mesothelioma cell lines. Moreover, Quercetin + Cisplatin lead to accumulation of both SPC111 and SPC212 cell lines in S phase.
METHODS: In present work, 84 genes involved in cell growth and proliferation have analysed by using RT(2)-PCR array system and protein profile of mitogen activated protein kinase (MAPK) family proteins investigated by western blots.
RESULTS: Our results showed that Quercetin and Quercetin + Cisplatin modulated gene expression of cyclins, cyclin dependent kinases and cyclin dependent kinases inhibitors. In addition genes involved in JNK, p38 and MAPK/ERK pathways were up regulated. Moreover, while p38 and JNK phosphorylations were increased, ERK phosphorylations were decreased after using Quercetin + Cisplatin.
CONCLUSION: This research has clarified our previous results and detailed mechanism of anti-carcinogenic potential of Quercetin alone and incombination with Cisplatin on malignant mesothelioma cells.

Shin SS, Park SS, Hwang B, et al.
MicroRNA-106a suppresses proliferation, migration, and invasion of bladder cancer cells by modulating MAPK signaling, cell cycle regulators, and Ets-1-mediated MMP-2 expression.
Oncol Rep. 2016; 36(4):2421-9 [PubMed] Related Publications
Despite the clinical significance of tumorigenesis, little is known about the cellular signaling networks of microRNAs (miRs). Here we report a new finding that mir‑106a regulates the proliferation, migration, and invasion of bladder cancer cells. Basal expression levels of mir‑106a were significantly lower in bladder cancer cells than in normal urothelial cells. Overexpression of mir‑106a suppressed the proliferation of bladder cancer cell line EJ. Transient transfection of mir‑106a into EJ cells led to downregulation of ERK phosphorylation and upregulation of p38 and JNK phosphorylation over their levels in the control. Flow cytometry analysis revealed that mir‑106a-transfected cells accumulated in the G1-phase of the cell cycle, and cyclin D1 and CDK6 were significantly downregulated. This G1-phase cell cycle arrest was due in part to the upregulation of p21CIP1/WAF1. In addition, mir‑106a overexpression blocked the wound-healing migration and invasion of EJ cells. Furthermore, mir‑106a transfection resulted in decreased expression of MMP-2 and diminished binding activity of transcription factor Ets-1 in EJ cells. Collectively, we report the novel mir‑106a-mediated molecular signaling networks that regulate the proliferation, migration, and invasion of bladder cancer cells, suggesting that mir‑106a may be a therapeutic target for treating advanced bladder tumors.

Sheikh A, Takatori A, Hossain MS, et al.
Unfavorable neuroblastoma prognostic factor NLRR2 inhibits cell differentiation by transcriptional induction through JNK pathway.
Cancer Sci. 2016; 107(9):1223-32 [PubMed] Free Access to Full Article Related Publications
The novel human gene family encoding neuronal leucine rich repeat (NLRR) proteins were identified as prognostic markers from our previous screening of primary neuroblastoma (NB) cDNA libraries. Of the NLRR gene family members, NLRR1 and NLRR3 are associated with the regulation of cellular proliferation and differentiation, respectively. However, the functional regulation and clinical significance of NLRR2 in NB remain unclear. Here, we evaluated the differential expression of NLRR2, where high expressions of NLRR2 were significantly associated with a poor prognosis of NB (P = 0.0009), in 78 NBs. Enforced expression of NLRR2 in NB cells enhanced cellular proliferation and induced resistance to retinoic acid (RA)-mediated cell growth inhibition. In contrast, knockdown of NLRR2 exhibited growth inhibition effects and enhanced RA-induced cell differentiation in NB cells. After RA treatment, NLRR2 expression was increased and correlated with the upregulation of c-Jun, a member of the activator protein-1 (AP-1) family in NB cells. Moreover, the expressions of NLRR2 and c-Jun were suppressed by treatment with a JNK inhibitor, which ameliorated the promoter activity of the NLRR2 gene while knockdown of c-Jun reduced NLRR2 expression. We then searched AP-1 binding consensus in the NLRR2 promoter region and confirmed c-Jun recruitment at a consensus. Conclusively, NLRR2 must be an inducible gene regulated by the JNK pathway to enhance cell survival and inhibit NB cell differentiation. Therefore, NLRR2 should have an important role in NB aggressiveness and be a potential therapeutic target for the treatment of RA resistant and aggressive NB.

Wang Z, Wang W, Xu S, et al.
The role of MAPK signaling pathway in the Her-2-positive meningiomas.
Oncol Rep. 2016; 36(2):685-95 [PubMed] Free Access to Full Article Related Publications
Meningiomas are common types of adult nerve system tumors. Although most cases are considered benign, due to its high rate of recurrence and easy malignant progression to anaplastic meningioma they present a puzzle for the current treatment. The HER-2 oncogene has important value for meningioma cells development and progression. So far, little is known about the effect on the exact underlying signal pathway and molecular mechanisms of HER-2-positive meningioma cells. The goal of the present study was to determine the effects of HER-2 gene and possible involvement of MAPK signal pathway in human malignant meningioma. We applied q-PCR analysis, immunofluorescence (IF) staining, western blot analysis, animal model, MAPK inhibition, MTT assay and cell invasion analysis for the investigation. The results demonstrated that the downregulation of the expression of HER-2 significantly inhibited cell motility and proliferation of human meningioma cells in vivo. Accordingly, in the HER-2-overexpression meningioma cells with the inhibition of ERK1/2, ERK5, JNK, in the cells with the ERK1/2, ERK5 inhibition, protein expression was markedly suppressed as well as the cell proliferation resistance. No difference was observed in the HER-2-overexpression meningioma cells with the inhibition of JNK. These findings suggest that HER-2 gene can affect the proliferation ability of human meningioma cells in vivo and MAPK signal pathway may contribute to the carcinogenesis and development of human meningiomas combinating with HER-2.

Yang GY, Zhang AQ, Wang J, et al.
Hepatoma-derived growth factor promotes growth and metastasis of hepatocellular carcinoma cells.
Cell Biochem Funct. 2016; 34(4):274-85 [PubMed] Related Publications
We aimed to elucidate the effects of hepatoma-derived growth factor (HDGF) on growth and metastasis of hepatocellular carcinoma (HCC) cells. Tissue microarrays with 236 HCC specimens and 18 extrahepatic metastases were utilized to detect the HDGF expression by immunohistochemistry. Meanwhile, HDGF expressions in HCC cell lines with different metastatic potentials were examined using immunofluorescence staining, real-time PCR and western blotting. After HDGF silencing, the growth and metastatic potentials of HCC cells were evaluated by soft agar assay, invasion assay, together with tumorigenicity assay in nude mice. The gelatin zymography was performed by detecting MMP-2 and MMP-9 levels. Additionally, western blotting was conducted to determine the levels of total and phosphorylated ERK1/2, JNK, p38 and Akt. The results showed that HDGF was overexpressed in HCC metastasis tumour, and the expression increased with the differentiation degree of tumours (Grade I 44.0%, Grade II 48.4% and Grade III 65.6%). Consistently, HDGF levels were positively associated with the metastatic capability of HCC cells (MHCC97L < MHCC97H < HCCLM3). The growth and metastasis were suppressed by HDGF-siRNA. Gelatinolytic activities were enhanced in the three metastatic HCC cell lines, but had no significant difference among them. The tumourigenicity and metastatic capability of HCCLM3 cells in nude mice were inhibited after silencing HDGF. Meanwhile, HDGF-siRNA specifically suppressed the total and phosphorylated protein levels of ERK1/2, while not JNK, p38 and Akt. In conclusion, HDGF was overexpressed in HCC patients and cells, and HDGF might be closely correlated with HCC metastasis via regulating ERK signalling pathway. Copyright © 2016 John Wiley & Sons, Ltd.

Chantana C, Yenjai C, Reubroycharoen P, Waiwut P
Combination of Nimbolide and TNF-α-Increases Human Colon Adenocarcinoma Cell Death through JNK-mediated DR5 Up- regulation.
Asian Pac J Cancer Prev. 2016; 17(5):2637-41 [PubMed] Related Publications
Tumor necrosis factor (TNF-α), an inflammatory cytokine that plays an important role in the control of cell proliferation, differentiation, and apoptosis, has previously been used in anti-cancer therapy. However, the therapeutic applications of TNF-α are largely limited due to its general toxicity and anti-apoptotic influence. To overcome this problem, the present study focused on the effect of active constituents isolated from a medicinal plant on TNF-α-induced apoptosis in human colon adenocarcinoma (HT-29) cells. Nimbolide from Azadirachta indica was evaluated for cytotoxicity by methyl tetrazolium 3-[4,5-dimethylthiazol-2-yl]-2, 5-diphenyltetrazolium bromide (MTT) assay and phase contrast microscopy. Effects on apoptotic signaling proteins were investigated using Western blot analysis. Nimbolide showed cytotoxicity against HT-29 cells that was significantly different from the control group (<0.01), a concentration of 10 μM significantly inducing cell death (<0.01). In combination with TNF-α, nimbolide significantly enhanced-induced cell death. In apoptotic pathway, nimbolide activated c-Jun N-terminal kinase (JNK) phosphorylation, BH3 interacting-domain death agonist (Bid) and up-regulated the death receptor 5 (DR5) level. In the combination group, nimbolide markedly sensitized TNF-α-induced JNK, Bid, caspase-3 activation and the up-regulation of DR5. Our findings overall indicate that nimbolide may enhance TNF-α-mediated cellular proliferation inhibition through increasing cell apoptosis of HT-29 cells by up-reglation of DR5 expression via the JNK pathway.

Wu CF, Bohnert S, Thines E, Efferth T
Cytotoxicity of Salvia miltiorrhiza Against Multidrug-Resistant Cancer Cells.
Am J Chin Med. 2016; 44(4):871-94 [PubMed] Related Publications
Salvia miltiorrhiza Bunge (Lamiaceae) is a well-known Chinese herb that possesses numerous therapeutic activities, including anticancer effects. In this study, the cytotoxicity and the biological mechanisms of S. miltiorrhiza (SM) root extract on diverse resistant and sensitive cancer cell lines were investigated. CEM/ADR5000 cells were 1.68-fold resistant to CCRF-CEM cells, while HCT116 (p53[Formula: see text] and U87.MG[Formula: see text]EGFR cells were hypersensitive (collateral sensitive) compared to their parental cells. SM root extract stimulated ROS generation, cell cycle S phase arrest and apoptosis. The induction of the intrinsic apoptotic pathway was validated by increased cleavage of caspase 3, 7, 9 and poly ADP-ribose polymerase (PARP). MAP kinases including JNK, ERK1/2 and p38 were obviously phosphorylated and nuclear P65 was downregulated upon SM treatment. Transcriptome-wide COMPARE analysis revealed that the expression of encoding genes with diverse functions were associated with the cellular response to cryptotanshinone, one of the main constituents of SM root extract. In conclusion, SM root extract exerted profound cytotoxicity towards various sensitive and resistant cancer cells and induced the intrinsic apoptotic pathway.

Najem D, Bamji-Mirza M, Yang Z, Zhang W
Aβ-Induced Insulin Resistance and the Effects of Insulin on the Cholesterol Synthesis Pathway and Aβ Secretion in Neural Cells.
Neurosci Bull. 2016; 32(3):227-38 [PubMed] Related Publications
Alzheimer's disease (AD) is characterized by amyloid-β (Aβ) toxicity, tau pathology, insulin resistance, neuroinflammation, and dysregulation of cholesterol homeostasis, all of which play roles in neurodegeneration. Insulin has polytrophic effects on neurons and may be at the center of these pathophysiological changes. In this study, we investigated possible relationships among insulin signaling and cholesterol biosynthesis, along with the effects of Aβ42 on these pathways in vitro. We found that neuroblastoma 2a (N2a) cells transfected with the human gene encoding amyloid-β protein precursor (AβPP) (N2a-AβPP) produced Aβ and exhibited insulin resistance by reduced p-Akt and a suppressed cholesterol-synthesis pathway following insulin treatment, and by increased phosphorylation of insulin receptor subunit-1 at serine 612 (p-IRS-S612) as compared to parental N2a cells. Treatment of human neuroblastoma SH-SY5Y cells with Aβ42 also increased p-IRS-S612, suggesting that Aβ42 is responsible for insulin resistance. The insulin resistance was alleviated when N2a-AβPP cells were treated with higher insulin concentrations. Insulin increased Aβ release from N2a-AβPP cells, by which it may promote Aβ clearance. Insulin increased cholesterol-synthesis gene expression in SH-SY5Y and N2a cells, including 24-dehydrocholesterol reductase (DHCR24) and 3-hydroxy-3-methyl-glutaryl-CoA reductase (HMGCR) through sterol-regulatory element-binding protein-2 (SREBP2). While Aβ42-treated SH-SY5Y cells exhibited increased HMGCR expression and c-Jun phosphorylation as pro-inflammatory responses, they also showed down-regulation of neuro-protective/anti-inflammatory DHCR24. These results suggest that Aβ42 may cause insulin resistance, activate JNK for c-Jun phosphorylation, and lead to dysregulation of cholesterol homeostasis, and that enhancing insulin signaling may relieve the insulin-resistant phenotype and the dysregulated cholesterol-synthesis pathway to promote Aβ release for clearance from neural cells.

Zhao HF, Wang J, Jiang HR, et al.
PI3K p110β isoform synergizes with JNK in the regulation of glioblastoma cell proliferation and migration through Akt and FAK inhibition.
J Exp Clin Cancer Res. 2016; 35:78 [PubMed] Free Access to Full Article Related Publications
BACKGROUND: Glioblastoma multiforme is the most aggressive malignant primary brain tumor, characterized by rapid growth and extensive infiltration to neighboring normal brain parenchyma. Both PI3K/Akt and JNK pathways are essential to glioblastoma cell survival, migration and invasion. Due to their hyperactivation in glioblastoma cells, PI3K and JNK are promising targets for glioblastoma treatment.
METHODS: To investigate the combination effects of class IA PI3K catalytic isoforms (p110α, p110β and p110δ) and JNK inhibition on tumor cell growth and motility, glioblastoma cells and xenografts in nude mice were treated with isoform-selective PI3K inhibitors in combination with JNK inhibitor.
RESULTS: We showed that combined inhibition of these PI3K isoforms and JNK exerted divergent effects on the proliferation, migration and invasion of glioblastoma cells in vitro. Pharmacological inhibition of p110β or p110δ, but not p110α, displayed synergistic inhibitory effect with JNK inhibition on glioblastoma cell proliferation and migration through decreasing phosphorylation of Akt, FAK and zyxin, leading to blockade of lamellipodia and membrane ruffles formation. No synergistic effect on invasion was observed in all the combination treatment. In vivo, combination of p110β and JNK inhibitors significantly reduced xenograft tumor growth compared with single inhibitor alone.
CONCLUSION: Concurrent inhibition of p110β and JNK exhibited synergistic effects on suppressing glioblastoma cell proliferation and migration in vitro and xenograft tumor growth in vivo. Our data suggest that combined inhibition of PI3K p110β isoform and JNK may serve as a potent and promising therapeutic approach for glioblastoma multiforme.

Zhang W, Sun J, Luo J
High Expression of Rab-like 3 (Rabl3) is Associated with Poor Survival of Patients with Non-Small Cell Lung Cancer via Repression of MAPK8/9/10-Mediated Autophagy.
Med Sci Monit. 2016; 22:1582-8 [PubMed] Free Access to Full Article Related Publications
BACKGROUND Rab-like 3 (Rabl3) is a member of the Rab subfamily of small GTPases which are involved in controlling proliferation and vesicular trafficking. Recent studies suggest that Rab proteins might play a critical role in regulating cancer cell survival, but the underlying mechanisms remain largely unknown. MATERIAL AND METHODS We performed a bioinformatics analysis to examine the correlation between the expression level of Rabl3 and survival of non-small cell lung cancer (NSCLC) patients in three independent cohorts containing 484 patients. The function of Rabl3 was examined in NSCLC cell line A549 in vitro. Following Rabl3 knockdown, cells were stained with propidium iodine (PI) and Annexin V, followed by flow cytometry analysis (FACS) for cell death and autophagy induction. The activity of the MAPK signaling pathway was assessed by Western blotting of different MAPK phosphorylations, and modulated with different chemical inhibitors. RESULTS High expression of Rabl3 was significantly correlated with poor survival in all three independent NSCLC cohorts. In line with this result, Rabl3 was frequently overexpressed in lung cancer cell lines as compared with normal lung fibroblast cell lines. Knockdown of Rabl3 in lung cancer cells significantly enhanced cell death accompanied with autophagy induction, as evidenced by an increased level of autophagy marker LC3-II. Interestingly, Rabl3 knockdown was associated with enhanced activation of MAPK8/9/10 but not MAPK11/12/13/14. Treatment of MAPK8/9/10-specific inhibitor SP600125, but not MAPK11/12/13/14-specific inhibitor SB203580, largely abolished Rabl3 knockdown-induced LC3-I/LC3-II conversion and autophagic cell death. CONCLUSIONS Together, these results suggest that high expression of Rabl3 might inhibit cell death in NSCLCs via repression of MAPK8/9/10-mediated autophagy.

Guo YX, Lin ZM, Wang MJ, et al.
Jungermannenone A and B induce ROS- and cell cycle-dependent apoptosis in prostate cancer cells in vitro.
Acta Pharmacol Sin. 2016; 37(6):814-24 [PubMed] Free Access to Full Article Related Publications
AIM: Jungermannenone A and B (JA, JB) are new ent-kaurane diterpenoids isolated from Chinese liverwort Jungermannia fauriana, which show anti-proliferation activities in cancer cells. In this study we investigated the mechanisms underlying the anticancer action of JA and JB in PC3 human prostate cancer cells in vitro.
METHODS: A panel of 9 human cancer cell lines was tested. Cell proliferation was assessed with a real-time cell analyzer and MTT assay. Cell apoptosis, cell cycle distribution and ROS levels were measured using cytometry. Mitochondrial damage was examined by transmission electron microscopy. DNA damage was detected with comet assay. Apoptotic, DNA damage- and cell cycle-related proteins were analyzed using Western blotting. The expression of DNA repair genes was measured with qRT-PCR.
RESULTS: Both JA and JB exerted potent anti-proliferative action against the 9 cancer cell lines, and PC3 cells were more sensitive with IC50 values of 1.34±0.09 and 4.93±0.20 μmol/L, respectively. JA (1.5 μmol/L) and JB (5 μmol/L) induced PC3 cell apoptosis, which was attenuated by the caspase inhibitor Z-VAD. Furthermore, both JA and JB caused mitochondrial damage and ROS accumulation in PC3 cells, whereas vitamin C blocked the ROS accumulation and attenuated the cytotoxicity of JA and JB. Moreover, both JA and JB induced DNA damage, accompanied by downregulated DNA repair proteins Ku70/Ku80 and RDA51. JA induced marked cell cycle arrest at the G0/G1 phase, which was related to c-Myc suppression, whereas JB enforced the cell cycle blockade in the G2/M phase, which associated with activation of the JNK signaling.
CONCLUSION: Both JA and JB induce prostate cancer apoptosis via ROS accumulation and induction of cell cycle arrest.

Foo JB, Saiful Yazan L, Tor YS, et al.
Dillenia suffruticosa dichloromethane root extract induced apoptosis towards MDA-MB-231 triple-negative breast cancer cells.
J Ethnopharmacol. 2016; 187:195-204 [PubMed] Related Publications
ETHNOPHARMACOLOGICAL RELEVANCE: Dillenia suffruticosa is traditionally used for treatment of cancerous growth including breast cancer in Malaysia.
AIM OF THE STUDY: Dillenia suffruticosa is a well-known medicinal plant in Malaysia for the treatment of cancer. Nevertheless, no study has been reported the cytotoxicity of this plant towards MDA-MB-231 triple-negative breast cancer cells. The present study was designed to investigate the mode of cell death and signalling pathways of MDA-MB-231 cells treated with dichloromethane Dillenia suffruticosa root extract (DCM-DS).
METHODS: Extraction of Dillenia suffruticosa root was performed by the use of sequential solvent procedure. The cytotoxicity of DCM-DS was determined by using MTT assay. The mode of cell death was evaluated by using an inverted light microscope and flow cytometry analysis using Annexin-V/PI. Cell cycle analysis and measurement of reactive oxygen species level were performed by using flow cytometry. The cells were treated with DCM-DS and antioxidants α-tocopherol or ascorbic acid to evaluate the involvement of ROS in the cytotoxicity of DCM-DS. Effect of DCM-DS on the expression of antioxidant, apoptotic, growth, survival genes and proteins were analysed by using GeXP-based multiplex system and Western blot, respectively. The cytotoxicity of compounds isolated from DCM-DS was evaluated towards MDA-MB-231 cells using MTT assay.
RESULTS: DCM-DS induced apoptosis, G2/M phase cell cycle arrest and oxidative stress in MDA-MB-231 cells. The induction of apoptosis in MDA-MB-231 cells by DCM-DS is possibly due to the activation of pro-apoptotic JNK1 and down-regulation of anti-apoptotic ERK1, which in turn down-regulates anti-apoptotic BCL-2 to increase the BAX/BCL-2 ratio to initiate the mitochondrial apoptotic pathway. The cell cycle arrest in DCM-DS-treated MDA-MB-231 cells is possibly via p53-independent but p21-dependent pathway. A total of 3 triterpene compounds were isolated from DCM-DS. Betulinic acid appears to be the most major and most cytotoxic compound in DCM-DS.
CONCLUSION: The data suggest the potential application of DCM-DS in the treatment of triple-negative breast cancer.

Zhang Y, Lin L, Jin Y, et al.
Overexpression of WNT5B promotes COLO 205 cell migration and invasion through the JNK signaling pathway.
Oncol Rep. 2016; 36(1):23-30 [PubMed] Related Publications
WNT5B is a member of the WNT family that has been reported to be overexpressed in a variety of cancer cell lines and tissues, including colorectal cancer (CRC). However, the potential roles of WNT5B in tumorigenesis have not been reported. In the present study, the WNT5B gene was transfected into CRC cells and generated a COLO 205 cell line with stable overexpression of WNT5B. MTT, wound healing and Transwell assays showed that overexpression of WNT5B significantly increased cell proliferation, migration and invasion capacities of the COLO 205 cells in vitro. Meanwhile, western blotting demonstrated that cells with stable expression of WNT5B showed increased protein expression levels and activities of matrix metalloproteinase (MMP) 2 and MMP 9. In addition, we also observed activation of the WNT/JNK signaling pathway in WNT5B-overexpressing cells. Subsequently, c-jun NH2-terminal kinase (JNK) was knocked down by RNA interference in the WNT5B-overexpressing COLO 205 cells. Knockdown of JNK significantly reduced the migratory capacity of the COLO 205 cells and decreased protein expression levels and activities of MMP 2 and 9 in vitro. In conclusion, our findings suggest that WNT5B may play an important role in the tumorigenesis of CRC.

Chuang WL, Lin PY, Lin HC, Chen YL
The Apoptotic Effect of Ursolic Acid on SK-Hep-1 Cells is Regulated by the PI3K/Akt, p38 and JNK MAPK Signaling Pathways.
Molecules. 2016; 21(4):460 [PubMed] Related Publications
Ursolic acid (UA) is a pentacyclic triterpene acid that is present in a wide variety of medicinal herbs and edible plants. This study investigated the effect of UA on apoptosis and proliferation of hepatocellular carcinoma SK-Hep-1 cells. After treatment of SK-Hep-1 cells with different concentrations of UA, we observed that cell viability was reduced in a dose- and time-dependent manner. Furthermore, there was a dose-dependent increase in the percentage of cells in the sub-G1 and G2/M phases, with cells treated with 60 μM showing the highest percentages of cells in those phases. UA-induced chromatin condensation of nuclei was observed by using DAPI staining. The western blot results revealed that exposure to UA was associated with decreased expression of the anti-apoptotic proteins Mcl-1, Bcl-xL, Bcl-2, and TCTP and increased expression of apoptosis-related proteins TNF-α, Fas, FADD, Bax, cleaved caspase-3, caspase-8, caspase-9, and PARP. Immunocytochemistry staining showed that treatment with UA resulted in increased expression of caspase-3. Moreover, exposure to UA resulted in the inhibition of the PI3K/Akt and p38 MAPK signaling pathways. These findings suggest that UA inhibits the proliferation of SK-Hep-1 cells and induces apoptosis.

Zhao M, Luo R, Liu Y, et al.
miR-3188 regulates nasopharyngeal carcinoma proliferation and chemosensitivity through a FOXO1-modulated positive feedback loop with mTOR-p-PI3K/AKT-c-JUN.
Nat Commun. 2016; 7:11309 [PubMed] Free Access to Full Article Related Publications
The biological role of miR-3188 has not yet been reported in the context of cancer. In this study, we observe that miR-3188 not only reduces cell-cycle transition and proliferation, but also significantly prolongs the survival time of tumour-bearing mice as well as sensitizes cells to 5-FU. Mechanistic analyses indicate that miR-3188 directly targets mTOR to inactivate p-PI3K/p-AKT/c-JUN and induces its own expression. This feedback loop further suppresses cell-cycle signalling through the p-PI3K/p-AKT/p-mTOR pathway. Interestingly, we also observe that miR-3188 direct targeting of mTOR is mediated by FOXO1 suppression of p-PI3K/p-AKT/c-JUN signalling. In clinical samples, reduced miR-3188 is an unfavourable factor and negatively correlates with mTOR and c-JUN levels but positively correlates with FOXO1 expression. Our studies demonstrate that as a tumour suppressor, miR-3188 directly targets mTOR to stimulate its own expression and participates in FOXO1-mediated repression of cell growth, tumorigenesis and NPC chemotherapy resistance.

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