• Korean Journal of Pharmacognosy
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• v.44 no.3
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• pp.269-274
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• 2013

In this study, we investigated the anticancer effect of rice bran extract in HL-60 human promyelocytic leukemia cells. The extract of rice bran inhibited the proliferation of HL-60 cells. When treated with the rice bran extract, we could observe the apoptotic characteristics such as apoptotic bodies and the increase of sub-G1 hypodiploid cell population, increase of Bax level, decrease of Bcl-2 expression, cleavage of procaspase-3, cleavage of procaspase-9 and cleavage of poly(ADP-ribose) polymerase(PARP) in HL-60 cells. Furthermore, the apoptosis induction of HL-60 cells treated with the rice bran extract was also accompanied by the inactivation of mitogen-activated protein kinases (MAPK) such as ERK1/2 MAPK and p38 MAPK. In addition, the rice bran extract induced the down-regulation of c-myc. These data suggested that the rice bran extract could induce the apoptosis via the inactivation of ERK1/2 MAPK and p38 MAPK, and the down-regulation of c-myc in HL-60 acute pomyelocytic leukemia cells. The results support that the rice bran extract might have potential for the treatment of acute promyelocytic leukemia.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.20
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• pp.8539-8548
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• 2014

Mitogen-activated protein kinase (MAPK) is an important signaling pathway in living beings in response to extracellular stimuli. There are 5 main subgroups manipulating by a set of sequential actions: ERK(ERK1/ERK2), c-Jun N(JNK/SAPK), p38 MAPK($p38{\alpha}$, $p38{\beta}$, $p38{\gamma}$ and $p38{\delta}$), and ERK3/ERK4/ERK5. When stimulated, factors of upstream or downstream change, and by interacting with each other, these groups have long been recognized to be related to multiple biologic processes such as cell proliferation, differentiation, death, migration, invasion and inflammation. However, once abnormally activated, cancer may occur. Several components of the MAPK network have already been proposed as targets in cancer therapy, such as p38, JNK, ERK, MEK, RAF, RAS, and DUSP1. Among them, alteration of the RAS-RAF-MEK-ERK-MAPK(RAS-MAPK) pathway has frequently been reported in human cancer as a result of abnormal activation of receptor tyrosine kinases or gain-of-function mutations in genes. The reported roles of MAPK signaling in apoptotic cell death are controversial, so that further in-depth investigations are needed to address these controversies. Based on an extensive analysis of published data, the goal of this review is to provide an overview on recent studies about the mechanism of MAP kinases, and how it generates certain tumors, as well as related treatments.

• Molecules and Cells
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• v.21 no.3
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• pp.367-375
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• 2006

We previously identified a novel cancer/testis antigen gene CAGE by screening cDNA expression libraries of human testis and gastric cancer cell lines with sera of gastric cancer patients. CAGE is expressed in many cancers and cancer cell lines, but not in normal tissues apart from the testis. In the present study, we investigated its role in the motility of cells of two human cancer cell lines: HeLa and the human hepatic cancer cell line, SNU387. Induction of CAGE by tetracycline or transient transfection enhanced the migration and invasiveness of HeLa cells, but not the adhesiveness of either cell line. Overexpression of CAGE led to activation of ERK and p38 MAPK but not Akt, and inhibition of ERK by PD98059 or p38 MAPK by SB203580 counteracted the CAGE-promoted increase in motility in both cell lines. Overexpression of CAGE also resulted in a reduction of ROS and an increase of ROS scavenging, associated with induction of catalase activity. Inhibition of ERK and p38 MAPK increased ROS levels in cells transfected with CAGE, suggesting that ROS reduce the motility of both cell lines. Inhibition of ERK and p38 MAPK reduced the induction of catalase activity resulting from overexpression of CAGE, and inhibition of catalase reduced CAGE-promoted motility. We conclude that CAGE enhances the motility of cancer cells by activating ERK and p38 MAPK, inducing catalase activity, and reducing ROS levels.

• Korean Journal of Clinical Laboratory Science
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• v.52 no.1
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• pp.62-68
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• 2020

Cisplatin (CDDP) is a chemotherapy agent used for patients with ovarian cancers. CDDP activates multiple signaling pathways, which causes various cellular reactions according to the type of cancer cells. Therefore, it is difficult to clearly conclude its signaling pathways. The purpose of this study is to determine the role of the signal protein of Akt/ERK1/2 and MAPK by CDDP-induced apoptosis in ovarian cancer cells (SKOV3). As a result, the number of apoptosis increased according to the TUNEL assay, and flow cytometric analysis confirmed that the percentage of sub-G1 early apoptosis was 8.73% higher than the control. The PARP and caspase-3 activity that appeared in the process of apoptosis was increased and the Bcl-2 expression was decreased. It was verified that the Akt and ERK1/2 activity was decreased, and p38 and JNK activity increased in a time dependent fashion. In conclusion, these results demonstrate that cisplatin inhibits the proliferation of ovarian cancer cells by inhibiting Akt activity and induces apoptosis by modulating the MAPK signaling pathway. However, a decrease in the ERK1/2 activity by CDDP was the opposite result to the result shown from the HeLa cells. For this reason, further research on signaling pathways is necessary. These results are expected to be useful for ovarian cancer treatment strategies targeting the MAPK pathway.

• Biomedical Science Letters
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• v.12 no.3
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• pp.249-254
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• 2006

It has been reported that liver is a very important organ to xenotransplantation. Pig is known to be a most suitable species in transplantation of human organs. However, the physiological function of pig hepatocytes is not clear elucidated. Epidermal growth factor (EGF) is known to be a mitogen in various cell systems. Thus, we examined the effect of EGF on cell proliferation and its related signal cascades in primary cultured pig hepatocytes. EGF stimulates cell proliferation in a dose (>1ng/ml) dependent manner. EGF-induced increase of $[^3H]-thymidine$ incorporation was blocked by AG 1478 ($10^{-6}M$, an EGF receptor antagonist) genistein and herbymycin A (tyrosine kinase inhibitors, $10^{-6}M$), suggesting the role of activation and tyrosine phosphorylation of EGF receptor. In addition, EGF-induced increase of $[^3H]-thymidine$ incorporation was prevented by neomycin $(10^{-4}M)$, U73122 $(10^{-5}M)$ (phospholipase C [PLC] inhibitors), staurosporine ($(10^{-8}M)$, or bisindolylmaleimide I $(10^{-6}M)$ (protein kinase C [PKC] inhibitors), suggesting the role of PLC and PKC. Moreover, EGF-induced increase of $[^3H]-thymidine$ incorporation was blocked by PD 98059 (a p44/42 mitogen activated protein kinase [MAPK] inhibitor), SB 203580 (a p38 MAPK inhibitor), and SP 600125 (a JNK inhibitor). EGF increased the translocation of PKC from cytosol to membrane fraction and activated p42/44 MAPK, p38 MAPK and JNK. In conclusion, EGF stimulates cell proliferation via PKC and MAPK in cultured pig hepatocytes.

• Molecules and Cells
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• v.40 no.1
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• pp.17-23
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• 2017

Mitogen-activated protein kinase (MAPK) signaling cascades play critical roles in various cellular events in plants, including stress responses, innate immunity, hormone signaling, and cell specificity. MAPK-mediated stress signaling is also known to negatively regulate nitrogen-fixing symbiotic interactions, but the molecular mechanism of the MAPK signaling cascades underlying the symbiotic nodule development remains largely unknown. We show that the MtMKK5-MtMPK3/6 signaling module negatively regulates the early symbiotic nodule formation, probably upstream of ERN1 (ERF Required for Nodulation 1) and NSP1 (Nod factor Signaling Pathway 1) in Medicago truncatula. The overexpression of MtMKK5 stimulated stress and defense signaling pathways but also reduced nodule formation in M. truncatula roots. Conversely, a MAPK specific inhibitor, U0126, enhanced nodule formation and the expression of an early nodulation marker gene, MtNIN. We found that MtMKK5 directly activates MtMPK3/6 by phosphorylating the TEY motif within the activation loop and that the MtMPK3/6 proteins physically interact with the early nodulation-related transcription factors ERN1 and NSP1. These data suggest that the stress signaling-mediated MtMKK5/MtMPK3/6 module suppresses symbiotic nodule development via the action of early nodulation transcription factors.

• Biomolecules & Therapeutics
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• v.30 no.6
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• pp.501-509
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• 2022

Atopic dermatitis (AD) is a chronic inflammatory skin disorder. Suppression of MAPKs and NF-κB is implicated as a vital mechanism of action of several traditional Chinese medicines for AD therapy. Although overexpression of MAPK mRNA in the skin tissue has been shown in the AD model, the roles of each MAPK in AD pathogenesis have rarely been studied. This study examined the effect of NJK14047, an inhibitor of p38 MAPKs, on AD-like skin lesions induced in BALB/c mice by sensitization and challenges with 1-chloro-2,4-dinitrobenzene (CDNB) on dorsal skin and ears, respectively. After induction of AD, NJK14047 (2.5 mg/kg) or dexamethasone (10 mg/kg) was administrated for 3 weeks via intraperitoneal injection. Following its administration, NJK14047 suppressed CDNB-induced AD-like symptoms such as skin hypertrophy and suppressed mast cell infiltration into the skin lesions. It also reduced CDNB-induced increase in T_H2 cytokine (IL-13) and T_H1 cytokines (interferon-γ and IL-12A) levels but did not decrease serum IgE level. Furthermore, NJK14047 blocked CDNB-induced lymph node enlargement. These results suggest that NJK14047, a p38 MAPK inhibitor, might be an optimal therapeutic option with unique modes of action for AD treatment.

• Biomolecules & Therapeutics
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• v.31 no.3
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• pp.276-284
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• 2023

Sinapic acid (SA) is a phenolic acid that is widely distributed in fruits and vegetables, which has various bioactivities, such as antidiabetic, anticancer and anti-inflammatory functions. Over-activated microglial is involved in the development progress of neurodegenerative diseases, such as Parkinson's disease and Alzheimer's disease. The objective of this study was to investigate the effect of SA in microglia neuroinflammation models. Our results demonstrated that SA inhibited secretion of the nitric oxide (NO) and interleukin (IL)-6, reduced the expression of inducible nitric oxide synthase (iNOS) and enhanced the release of IL-10 in a dose-dependent manner. Besides, our further investigation revealed that SA attenuated the phosphorylation of AKT and MAPK cascades in LPS-induced microglia. Consistently, oral administration of SA in mouse regulated the production of inflammation-related cytokines and also suppressed the phosphorylation of MAPK cascades and AKT in the mouse cerebral cortex. These results suggested that SA may be a possible therapy candidate for anti-inflammatory activity by targeting the AKT/MAPK signaling pathway.

• Korean Journal of Clinical Laboratory Science
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• v.53 no.3
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• pp.249-256
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• 2021

Asthma is a chronic inflammatory airway disease. There are many factors including genetic and environmental factors that influence asthma. The mitogen-activated protein kinase (MAPK) pathway is involved in maintaining the T helper cells 1 and 2 (Th1/Th2) balance and plays an important role in the development of asthma. In this study, the correlation between the NDFIP2 gene that regulates the MAPK pathway and asthma was analyzed. The genetic polymorphism of the NDFIP2 gene was analyzed between 193 asthma patients and 3,228 healthy controls in Korea. As a result, 4 single nucleotide polymorphisms (SNPs) showed a significant correlation (P<0.05) and high relative risk with asthma. Among them, rs2783122 of NDFIP2 showed a statistically significant association with asthma (P-value=9.76×10^-6, odds ratio (OR)=1.67, 95% confidence interval (CI)=1.33~2.10). In the SNP imputation on the NDFIP2, 16 SNPs were discovered, and all of them showed significant correlation with asthma and high odds ratio. The genotype-based mRNA expression analysis revealed that the group of minor alleles of rs1408049 showed increased mRNA expression. Increased NDFIP2 expression causes the activation of the MAPK pathway, and this may influence the development of asthma. In conclusion, the polymorphisms of NDFIP2 are associated with asthma development and this can provide the basis for new guidelines for the management of asthma in the Korean population.

• The korean journal of orthodontics
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• v.33 no.3 s.98
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• pp.199-210
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• 2003

Tooth movement is the result of bone metabolism in the periodontium, where various cytokines take important roles. Interleukin-6(II-6) and nitrous oxide (NO) were reported to be secreted from osteoblasts in the process of bone resorption. The mechanism of the process has not been clearly understood, but the activation of mitogen-activated protein kinase (MAPK) was known to be an important process in the release of the inflammatory cytotines in macrophages. In this regard, to prove the role of MAPK in the release of IL-6 and NO in MC3T3E-1 osteoblasts, Northern blot analysis, Western blot analysis and immune complex kinase assay were used. As a result, the treatment of MC3T3E-1 osteoblast cultures with combined $interferon-\gamma(IFN-\gamma)$, lipopolysaccharide (LPS) and tumor necrosis $factor-\alpha(TNF-\alpha)$ induces expressions of inducible nitric oxide synthase (iNOS) and IL-6, resulting in sustained releases of large amounts of NO and IL-6. However, $IFN-\gamma,\;LPS,\;and\;TNF-\alpha$ individually induce a non-detectable or small amount of NO and IL-6 in MC3T3E-1 osteoblasts. The role of MAPK activation in the early intracellular signal transduction involved in iNOS and IL-6 transcription in the combined agents-stimulated osteoblasts has been investigated. The p38 MAPK pathway is specifically involved in the combined agents-induced NO and IL-6 release, since NO and IL-6 release in the presence of a specific inhibitor of p38 MAPK, 4-(4-fluorophenyl)-2-(4-metylsulfinylphenyl)-5-(4-metylsulfinylphenyl)-5-(4-pyridyl)imidazole) (SB203580), were significantly diminished. In contrast, PD98059, a specific inhibitor of MEK1, had no effect on NO and IL-6 release. Northern blot analysis showed that the p3a MAPK pathway controlled the iNOS and IL-6 transcription level. These data suggest that p38 MAPK play an important role in the secretion of NO and IL-6 in $LPS/IFN{\gamma}-or\;TNF-\gamma-treated\;MC3T3E-1$ osteoblasts.