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Keratinocytes are susceptible to airborne particulate matter (PM) exposure, resulting in human skin barrier dysfunction. Therefore, it is important to find useful reagents to resolve skin damages caused by PM. Here, we explored the protective effect of 7S MaR1, a specialized pro-resolving mediator derived from docosahexaenoic acid, on skin inflammation and the oxidative stress induced by PM with a diameter 10 μm or less (PM10) in human keratinocyte HaCaT cells. Interestingly, PM10-induced ROS generation was modulated by 7S MaR1 via the recovery of ROS scavenger genes. 7S MaR1 reduced PM10-induced IL-6 expression via modulating the p38/ERK/NF-κB signaling pathways. These results demonstrate that PM 10 induces inflammatory cytokines, which can lead to skin diseases. In addition, 7S MaR1 can resolve inflammation caused by PM 10 -induced oxidative stress and inflammatory cytokines. [BMB Reports 2024; 57(11): 490-496].

Background: Cinnamomum verum J. Presl (Cinnamon) is widely used in the food and pharmaceutical industries. C. verum exhibits various biological activities. However, it is unclear whether C. verum can inhibit NOX, a major source of ROS generation, and exert anti-inflammatory and antioxidant effects in PMA-stimulated THP-1 cells., Purpose: This study investigates the anti-inflammatory and antioxidant effects of C. verum in PMA-stimulated THP-1 cells., Methods: The MeOH extract of C. verum was analyzed using UPLC-QTOF/MS. Anti-inflammatory and antioxidant effects of C. verum extract were examined by DCF-DA staining, immunofluorescence staining, RT-PCR, and immunoblotting in PMA-stimulated THP-1 cells., Results: C. verum and its components, cinnamic acid and coumarin, significantly attenuated the expression of IL-1β, IL-8, CCL5, and COX-2 in PMA-stimulated THP-1. C. verum decreased ROS levels via NOX2 downregulation, as well as ameliorated plasma membrane translocation of PKCδ and decreased JNK phosphorylation. Besides, C. verum suppressed the nuclear translocation of AP-1 and NF-κB, which modulates diverse pro-inflammatory genes., Conclusion: C. verum effectively inhibits inflammation and oxidative stress during monocyte-macrophage differentiation and downregulates inflammatory mediators via NOX2/ROS and PKCδ/JNK/AP-1/NF-κB signaling., Competing Interests: Declaration of Competing Interest The authors declare that they have no competing interest., (Copyright © 2023 The Author(s). Published by Elsevier GmbH.. All rights reserved.)

11 S, 17S-dihydroxy 7,9,13,15,19 (Z,E,Z,E,Z)-docosapentaenoic acid (DoPE) is a derivative of docosapentaenoic acid, a specialized pro-resolving mediator of inflammation such as lipoxins, resolvins, maresins, and protectins. PM 10 is a fine dust particle that induces oxidative stress, DNA damage, inflammation, aging, and cancer. The anti-inflammatory mechanism of DoPE, however, has not yet been elucidated. In these studies, we investigated whether DoPE has anti-inflammatory effects in human keratinocyte HaCaT cells. We demonstrated that DoPE suppressed PM 10 -induced expressions of IL-6 mRNA and protein in human HaCaT keratinocytes. We also investigated the modulating effects of DoPE on reactive oxygen species (ROS) and mitogen-activated protein kinase (MAPK). ROS production, extracellular signal regulated kinase (ERK) phosphorylation, and translocation of nuclear factor-kappa B (NF-kB) p65 and NF-kB activity were suppressed by DoPE in PM 10 -stimulated HaCaT cells. Collectively, our results demonstrated that DoPE inhibited IL-6 expression by reducing ROS generation, suppressing ERK phosphorylation, and inhibiting translocation of NF-kB p65 and NF-kB activity in PM 10 -stimulated HaCaT cells, suggesting that DoPE can be useful for the resolution of the inflammation caused by IL-6., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: IL-32 is a novel cytokine involved in many inflammatory diseases. However, the role of IL-32γ, an isotype of IL-32, in atopic dermatitis (AD) has not been reported., Objective: We investigated the effects of IL-32γ on development of AD and its action mechanisms., Methods: We used phthalic anhydride (PA) and an MC903-induced AD model using wild-type and IL-32γ transgenic mice. We conducted the therapy experiments by using recombinant IL-32γ protein in a reconstructed human skin model and PA-induced model. We conducted a receiver operating characteristic analysis of IL-32γ with new AD biomarkers, IL-31 and IL-33, in serum from patients with AD., Results: Dermatitis severity and epidermal thickness were significantly reduced in PA- and MC903-induced IL-32γ transgenic mice compared with in wild-type mice. The concentration of AD-related cytokines was reduced in PA- and MC903-induced IL-32γ transgenic mice compared with in wild-type mice. Subsequent analysis showed that IL-32γ inhibits miR-205 expression in PA- and MC903-induced skin tissue samples and TNF-α/IFN-γ-treated HaCaT cells. IL-32γ reduced NF-κB activity in skin tissue samples from PA- and MC903-induced mice and TNF-α/IFN-γ-treated HaCaT cells. NF-κB inhibitor treatment with IL-32γ expression further suppressed expression of inflammatory mediators as well as miR-205 in TNF-α/IFN-γ-treated HaCaT cells. Furthermore, recombinant IL-32γ protein alleviated AD-like inflammation in in vivo and reconstructed human skin models. Spearman correlation analysis showed that serum levels of IL-32γ and miR-205 were significantly concordant in patients with AD., Conclusion: Our results indicate that IL-32γ reduces AD through the inhibition of miR-205 expression via inactivation of NF-κB., (Copyright © 2020 The Authors. Published by Elsevier Inc. All rights reserved.)

Epimagnolin A is a lignan obtained from the flower buds of Magnolia fargesii, which is traditionally used in Asian medicine for treating headache and nasal congestion. A herbal compound fargesin obtained from M. fargesii, has exerted anti-inflammatory effects in human monocytic THP-1 cells in the previous study. The anti-inflammatory effects of epimagnolin A, however, have been not elucidated yet. In this study, it was demonstrated that epimagnolin A reduced phorbol-12-myristate-13-acetate (PMA)-induced IL-6 promoter activity and IL-6 production in human monocytic THP-1 cells. Furthermore, it was investigated the modulating effects of epimagnolin A on mitogen-activated protein kinase, nuclear factor-kappa B (NF-κB), and activator protein 1 (AP-1) activities. Phosphorylation of p38 and nuclear translocation of p50 and c-Jun were down-regulated by epimagnolin A in the PMA-stimulated THP-1 cell. The results revealed that epimagnolin A attenuated the binding affinity of NF-κB and AP-1 transcription factors to IL-6 promoter and IL-6 production through p38/NF-kB and AP-1 signaling pathways in the PMA-stimulated THP-1 cells. These results suggest that epimagnolin A can be a useful drug for the treatment of inflammatory diseases., (© 2019 Wiley Periodicals, Inc.)

Background: Interleukin-32 (IL-32) has been associated with various diseases. Previous studies have shown that IL-32 inhibited the development of several tumors. However, the role of IL-32γ, an isotype of IL-32, in skin carcinogenesis remains unknown., Methods: We compared 7,12-Dimethylbenz[a]anthracene/12-O-Tetradecanoylphorbol-13-acetate (DMBA/TPA)-induced skin carcinogenesis in wild type (WT) and IL-32γ-overexpressing mice to evaluate the role of IL-32γ. We also analyzed cancer stemness and NF-κB signaling in skin cancer cell lines with or without IL-32γ expression by western blotting, quantitative real-time PCR and immunohistochemistry analysis., Results: Carcinogen-induced tumor incidence in IL-32γ mice was significantly reduced in comparison to that in WT mice. Infiltration of inflammatory cells and the expression levels of pro-inflammatory mediators were decreased in the skin tumor tissues of IL-32γ mice compared with WT mice. Using a genome-wide association study analysis, we found that IL-32 was associated with integrin αV (ITGAV) and tissue inhibitor of metalloproteinase-1 (TIMP-1), which are critical factor for skin carcinogenesis. Reduced expression of ITGAV and TIMP-1 were identified in DMBA/TPA-induced skin tissues of IL-32γ mice compared to that in WT mice. NF-κB activity was also reduced in DMBA/TPA-induced skin tissues of IL-32γ mice. IL-32γ decreased cancer cell sphere formation and expression of stem cell markers, and increased chemotherapy-induced cancer cell death. IL-32γ also downregulated expression of ITGAV and TIMP-1, accompanied with the inhibition of NF-κB activity. In addition, IL-32γ expression with NF-κB inhibitor treatment further reduced skin inflammation, epidermal hyperplasia, and cancer cell sphere formation and downregulated expression levels of ITGAV and TIMP-1., Conclusions: These findings indicated that IL-32γ suppressed skin carcinogenesis through the inhibition of both stemness and the inflammatory tumor microenvironment by the downregulation of TIMP-1 and ITGAV via inactivation of NF-κB signaling.

The compound 6-O-veratroyl catalpol (6-O) is a bioactive iridoid glucoside that was originally isolated from Pseudolysimachion rotundum var. subintegrum. It has been demonstrated that catapol derivative iridoid glucosides including 6-O, possess anti-inflammatory activity in carragenan-induced paw edema mouse model as well as bronchoalveolar lavage fluid of ovalbumin-induced mouse model. In the present study, we investigated whether 6-O modulates inflammatory responses in THP-1 monocytic cells stimulated with phorbol12-myristate-13-acetate (PMA). Our data showed that 6-O inhibited PMA induced interleukin (IL)-1β and tumor necrosis factor (TNF)-α expression in THP-1 monocytic cells. Mechanistic studies revealed that 6-O suppressed the activity of protein kinase C (PKC), which further resulted in downstream inactivation of extracellular signal-regulated kinase (ERK) and nuclear factor-κB (NF-κB) inflammatory pathway. The results implied that 6-O may protect against inflammatory responses that could be a potential compound in treating inflammatory diseases., (Copyright © 2015. Published by Elsevier B.V.)

Numerous studies have been suggested that derivatives can improve the effects of original substances. Therefore, we made luteolin derivative luteolin 8-C-β-fucopyranoside (LU8C-FP) for better anti-inflammatory and anti-cancer effects. In a previous study, we demonstrated that LU8C-FP inhibits invasion of human breast cancer cells via suppression of matrix metalloproteinase 9 and IL-8, which play major roles in tumor progression and cancer cell invasion. Various stimuli trigger inflammatory responses by inducing pro-inflammatory cytokines and chemokines in THP-1 cells. IL-6 induces inflammation via inducing various cytokines and appears to be a potential mediator of inflammatory diseases. Here, we investigated the precise mechanism by which LU8C-FP inhibited phorbol 12-myristate 13-acetate-induced IL-6 mRNA and protein expression. We showed LU8C-FP downregulated IL-6 expression by inhibiting mitogen-activated protein kinases and the nuclear factor-kappaB signaling pathway in human monocytic cells. Furthermore, LU8C-FP exerts less cytotoxicity than luteolin and also it has specific inhibitory effect on IL-6 expression. However, luteolin has a variety of inhibitory effects on pro-inflammatory cytokines and chemokines. Our in vitro studies may provide valuable information leading to the use of LU8C-FP to treat inflammatory diseases caused by IL-6., (Copyright © 2015 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.)

Neuroinflammation is important for the development of several neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease, and stroke. Since changes of cytokine level are critical for neuroinflammation in the brain, we investigated whether IL-32α overexpression could change neuroinflammation and, thus, affect stroke development. Middle cerebral artery occlusion (MCAO) induced development of ischemia, and ischemic neuronal cell death were reduced in IL-32α-overexpressing transgenic mice (IL-32α mice) brain through the decreased release of neuroinflammatory cytokines (IL-6, IL-1β, TNF-α) and activation of astrocytes, but enhancement of anti-neuroinflammatory cytokines (IL-10). Reactive oxygen species generation and lipid peroxidation as well as expression of inducible nitric oxide and cyclooxygenase-2 were also reduced in the IL-32α mice brain. Nuclear factor-kappa B (NF-κB), a critical transcriptional factor regulating neuroinflammation, was much lower, but activation of signal transducer and activator of transcription 3 (STAT3), which plays a crucial role in cell survival and proliferation, was much higher in IL-32α-overexpressing mice brain compared to those of wild-type mice brain. These results suggest that IL-32α can prevent cerebral ischemia damage via upregulation of anti-neuroinflammatory cytokine expression and STAT3 activation, but downregulation of neuroinflammatory cytokines and NF-κB activation.

Cytokine and activation of lymphocytes are critical for tumor growth. We investigated whether interleukin (IL)-32β overexpression changes other cytokine levels and activates cytotoxic lymphocyte, and thus modify tumor growth. Herein, IL-32β inhibited B16 melanoma growth in IL-32β-overexpressing transgenic mice (IL-32β mice), and downregulated the expressions of anti-apoptotic proteins (bcl-2, IAP, and XIAP) and cell growth regulatory proteins (Ki-67 antigen (Ki-67) and proliferating cell nuclear antigen (PCNA)), but upregulated the expressions of pro-apoptotic proteins (bax, cleaved caspase-3, and cleaved caspase-9). IL-32β also inhibited colon and prostate tumor growth in athymic nude mice inoculated with IL-32β-transfected SW620 colon or PC3 prostate cancer cells. The forced expression of IL-32β also inhibited cell growth in cultured colon and prostate cancer cells, and these inhibitory effects were abolished by IL-32 small interfering RNA (siRNA). IL-10 levels were elevated, but IL-1β, IL-6, and tumor necrosis factor-alpha (TNF-α) levels were reduced in the tumor tissues and spleens of IL-32β mice, and athymic nude mice. The number of cytotoxic T (CD8(+)) and natural killer (NK) cells in tumor tissues, spleen, and blood was significantly elevated in IL-32β mice and athymic nude mice inoculated with IL-32β-transfected cancer cells. Constituted activated NF-κB and STAT3 levels were reduced in the tumor tissues of IL-32β mice and athymic nude mice, as well as in IL-32β-transfected cultured cancer cells. These findings suggest that IL-32β inhibits tumor growth by increasing cytotoxic lymphocyte numbers, and by inactivating the NF-κB and STAT3 pathways through changing of cytokine levels in tumor tissues.

Background and Purpose: The effects of 4-O-methylhonokiol (MH), a constituent of Magnolia officinalis, were investigated on human prostate cancer cells and its mechanism of action elucidated., Experimental Approach: The anti-cancer effects of MH were examined in prostate cancer and normal cells. The effects were validated in vivo using a mouse xenograft model., Key Results: MH increased the expression of PPARγ in prostate PC-3 and LNCap cells. The pull-down assay and molecular docking study indicated that MH directly binds to PPARγ. MH also increased transcriptional activity of PPARγ but decreased NF-κB activity. MH inhibited the growth of human prostate cancer cells, an effect attenuated by the PPARγ antagonist GW9662. MH induced apoptotic cell death and this was related to G(0) -G(1) phase cell cycle arrest. MH increased the expression of the cell cycle regulator p21, and apoptotic proteins, whereas it decreased phosphorylation of Rb and anti-apoptotic proteins. Transfection of PC3 cells with p21 siRNA or a p21 mutant plasmid on the cyclin D1/ cycline-dependent kinase 4 binding site abolished the effects of MH on cell growth, cell viability and related protein expression. In the animal studies, MH inhibited tumour growth, NF-κB activity and expression of anti-apoptotic proteins, whereas it increased the transcriptional activity and expression of PPARγ, and the expression of apoptotic proteins and p21 in tumour tissues., Conclusions and Implication: MH inhibits growth of human prostate cancer cells through activation of PPARγ, suppression of NF-κB and arrest of the cell cycle. Thus, MH might be a useful tool for treatment of prostate cancer., (© 2012 The Authors. British Journal of Pharmacology © 2012 The British Pharmacological Society.)

Biphenolic components in the Magnolia family have shown several pharmacological activities such as antitumor effects. This study investigated the effects of 4-O-methylhonokiol (MH), a constituent of Magnolia officinalis, on human colon cancer cell growth and its action mechanism. 4-O-methylhonokiol (0-30 μM) decreased constitutive activated nuclear factor (NF)-κB DNA binding activity and inhibited growth of human colon (SW620 and HCT116) cancer cells. It also caused G₀-G₁ phase cell cycle arrest followed by an induction of apoptotic cell death. However, knockdown with small interfering RNA (siRNA) of p21 or transfection with cyclin D1/Cdk4 binding site-mutated p21 abrogated MH-induced cell growth inhibition, inhibition of NF-κB activity as well as expression of cyclin D1 and Cdk4. Conversely, inhibition of NF-κB with specific inhibitor or siRNA augmented MH-induced apoptotic cell death. 4-O-methylhonokiol inhibited tumor growth, NF-κB activity and expression of antiapoptotic proteins; however, it increased the expression of apoptotic proteins as well as p21 in xenograft nude mice bearing SW620 cancer cells. The present study reveals that MH causes p21-mediated human colon cancer cell growth inhibition through suppression of NF-κB and indicates that this compound by itself or in combination with other anticancer agents could be useful for the treatment of cancer., (Copyright © 2012 Elsevier Inc. All rights reserved.)

IL-32 is a newly discovered cytokine. Recently, various reports suggest that it plays a role as a proinflammatory mediator and may be involved in several cancer carcinogenesis. However, IL-32 expression in hepatocellular carcinoma (HCC) remains unclear. In this study, we investigated the expression and role of IL-32α in hepatocellular carcinoma, because IL-32 was identified as an upregulated gene in hepatocellular carcinoma tissues compared to nontumorous regions using DNA microarray. IL-32α was overexpressed in tissue and serum from patients with HCC and localized in the cytoplasm and nucleus of hepatocellular carcinoma tumor cells. Moreover, secreted IL-32α concentration in the serum of patients with hepatocellular carcinoma was elevated as compared with those in the normal serum using a developed sandwich ELISA. Furthermore, IL-32α suppression in hepatocellular carcinoma decreased expression of phospho-p38 MAPK, NF-κB, and antiapoptotic protein Bcl-2 and induced expression of proapoptotic proteins as well as p53 and PUMA resulting in the suppression of cell growth and induction of intrinsic apoptosis. Based on our results, we suggest that IL-32α is involved in the progression of hepatocellular carcinoma and may be a useful biomarker for diagnosis and therapeutic target of hepatocellular carcinoma., (Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.)

To evaluate the relevance of C-C chemokine receptor type 5 (CCR5) expression and tumor development, we compared melanoma growth in CCR5 knockout (CCR5(-/-)) mice and wild type (CCR5(+/+)) mice. CCR5(-/-) mice showed reduced tumor volume, tumor weight, and increased survival rate when compared to CCR5(+/+) mice. We investigated the activation of NF-κB since it is an implicated transcription factor in the regulation of genes involving cell growth, apoptosis, and tumor growth. Significant inhibition of DNA binding activity of NF-κB, and translocation of p50 and p65 into the nucleus through the inhibition of phosphorylation of IκB was found in the melanoma tissues of CCR5(-/-) mice compared to melanoma tissues of CCR5(+/+) mice. NF-κB target apoptotic protein expression, such as cleaved caspase-3, cleaved PARP, and Bax, was elevated, whereas the survival protein expression levels, such as Bcl-2, C-IAP1, was decreased in the melanoma tissues of CCR5(-/-) mice. Interestingly, we found that the level of IL-1Ra, a tumor growth suppressive cytokine, was significantly elevated in tumor tissue and spleen of CCR5(-/-) mice compared to the level in CCR5(+/+) mice. Moreover, infiltration of CD8(+) cytotoxic T cell and CD57(+) natural killer cells was significantly increased in melanoma tumor and spleen tissue of CCR5(-/-) mice compared to that of CCR5(+/+) mice. Therefore, these results showed that CCR5 deficiency caused apoptotic cell death of melanoma through inhibition of NF-κB and upregulation of IL-1Ra.

Several studies have shown physiological functions of interleukin (IL)-32, a novel cytokine. However, the role of IL-32 in cancer development has not been reported. In this study, we showed that IL-32γ inhibited tumor growth in IL-32γ-overexpressing transgenic mice inoculated with melanoma as well as colon tumor growth in xenograft nude mice inoculated with IL-32γ-transfected colon cancer cells (SW620). The inhibitory effect of IL-32γ on tumor growth was associated with the inhibition of constitutive activated nuclear transcription factor-κB (NF-κB) and of signal transducer and activator of transcription 3 (STAT3). The expression of antiapoptotic, cell proliferation and tumor-promoting genes (bcl-2, X-chromosome inhibitor of apoptosis protein (IAP), cellular IAP and cellular FADD-like IL-1β-converting enzyme-inhibitory protein, cyclin D), cyclin-dependent kinase 4, cycolooxygenase-2 and inducible nitric oxide synthase was decreased, whereas the expression of apoptotic target genes (caspase-3 and -9, bax) increased. In tumor, spleen and blood, the number of cytotoxic CD8(+) T cells and CD57(+) natural killer cells and the levels of IL-10 increased, but that of tumor necrosis factor-α (TNF-α), IL-1β and IL-6 decreased. We also found that forced overexpression of IL-32γ inhibited colon cancer cell (SW620 and HCT116) growth accompanied with the inhibition of activated NF-κB and STAT3 in vitro. In addition, when IL-32γ was knocked down by small interfering RNA (siRNA) or neutralized with an anti-IL-32γ antibody, IL-32γ-induced colon cancer cell growth inhibition, the IL-32γ-induced decrease of TNF-α, IL-1 and IL-6 production, and the increase of IL-10 production were abolished. However, siRNA of NF-κB and STAT3 augmented IL-32γ-induced colon cancer cell growth inhibition. These findings indicate significant pathophysiological roles of IL-32γ in cancer development.

Background: Bee venom has been used as a traditional medicine to treat arthritis, rheumatism, back pain, cancerous tumors, and skin diseases. However, the effects of bee venom on the prostate cancer and their action mechanisms have not been reported yet., Methods: To determine the effect of bee venom and its major component, melittin on the prostate cancer cells, apoptosis is analyzed by tunnel assay and apoptotic gene expression. For xenograft studies, bee venom was administrated intraperitoneally twice per week for 4 weeks, and the tumor growth was measured and the tumor were analyzed by immunohistochemistry. To investigate whether bee venom and melittin can inactivate nuclear factor kappa B (NF-κB), we assessed NF-κB activity in vitro and in vivo., Results and Conclusions: Bee venom (1-10 µg/ml) and melittin (0.5-2.5 µg/ml) inhibited cancer cell growth through induction of apoptotic cell death in LNCaP, DU145, and PC-3 human prostate cancer cells. These effects were mediated by the suppression of constitutively activated NF-κB. Bee venom and melittin decreased anti-apoptotic proteins but induced pro-apoptotic proteins. However, pan caspase inhibitor abolished bee venom and melittin-induced apoptotic cell death and NF-κB inactivation. Bee venom (3-6 mg/kg) administration to nude mice implanted with PC-3 cells resulted in inhibition of tumor growth and activity of NF-κB accompanied with apoptotic cell death. Therefore, these results indicated that bee venom and melittin could inhibit prostate cancer in in vitro and in vivo, and these effects may be related to NF-κB/caspase signal mediated induction of apoptotic cell death., (Copyright © 2010 Wiley-Liss, Inc.)

Ginsenoside Rg3 has been a subject of interest for use as a cancer preventive or therapeutic agent. Nuclear factor-kappa (NF-kappaB) is constitutively activated in prostate cancer, and gives cancer cells resistance to chemotherapeutic agents. To investigate whether Rg3 can suppress the activation of NF-kappaB, and thus increase susceptibility of prostate (LNCaP and PC-3, DU145) cells against chemotherapeutics, prostate cancer cell growth as well as activation of NF-kappaB was examined. We found that a combination treatment of Rg3 (50 microM) with a conventional agent docetaxel (5 nM) was more effective in the inhibition of prostate cancer cell growth and induction of apoptosis as well as G(0)/G(1) arrest accompanied with the significant inhibition of NF-kappaB activity than those by treatment of Rg3 or docetaxel alone. It was also found that NF-kappaB target gene expression of Bax, caspase-3, and caspase-9 was much more significantly enhanced, but the expression of Bcl-2, inhibitor of apoptosis protein (IAP-1) and X chromosome IAP (XIAP), and the expression of cell cycle regulatory proteins cyclin B, D1 and E, and cyclin dependent kinases 2 and 4 was also much more significantly inhibited by the combination treatment. The combination of Rg3 (50 microM) with cisplatin (10 microM) and doxorubicin (2 microM) was also more effective in the inhibition of prostate cancer cell growth and NF-kappaB activity than those by the treatment of Rg3 or chemotherapeutics alone. These results indicate that ginsenoside Rg3 inhibits NF-kappaB, and enhances the susceptibility of prostate cancer cells to docetaxel and other chemotherapeutics. Thus, ginsenoside Rg3 could be useful as an anti-cancer agent., (Copyright (c) 2009 Elsevier B.V. All rights reserved.)

Chemotherapeutic strategies commonly use multiple agents to overcome drug resistance and to lower drug toxicity. Activation of nuclear factor-kappaB (NF-kappaB) is implicated in drug resistance in cancer cells. Previously, we reported that thiacremonone, a novel sulfur compound isolated from garlic, inhibited NF-kappaB and cancer cell growth with IC(50) values about 100 microg/mL in colon cancer cells. In the present study, we tested whether thiacremonone could increase susceptibility of cancer cells to chemotherapeutics through inactivation of NF-kappaB. Colon cancer cells were cotreated with thiacremonone (50 microg/mL, half dose of IC(50)) and lower doses of each chemotherapeutic agent (half dose of IC(50)) for 24 hours. NF-kappaB activity was completely abrogated in cells treated with a combination of thiacremonone and docetaxel, whereas thiacremonone on its own did not alter NF-kappaB activity. This combined drug effect was also found with other anticancer drugs in colon cancer and in other cancer cells. In good correlation with inhibition of cell growth and NF-kappaB activity, the combination treatment also regulated NF-kappaB target genes. Oral treatment of mice with thiacremonone (1 mg/kg) by administering it in drinking water for 4 weeks significantly augmented docetaxel (1 mg/kg, i.p., four times)-induced decrease of tumor growth accompanied with regulation of NF-kappaB activity and NF-kappaB target genes. These results warrant carefully designed clinical studies investigating the combination of thiacremonone and commonly used chemotherapeutic agents for the treatment of human cancers.

Mac-2BP is a ligand of the galectin family that has been suggested to affect tumor proliferation and metastasis formation. We assessed Mac-2BP expression at the transcriptional and translational levels to evaluate nerve growth factor (NGF)-induced Mac-2BP expression. A time kinetic analysis using reverse transcription-polymerase chain reaction showed that NGF-induced Mac-2BP transcript levels were 4-5 times higher than in controls. Mac-2BP enzyme-linked immunosorbent assay and immunofluorescence staining showed a 2-3-fold increase in intracellular and secreted Mac-2BP as a result of NGF stimulation. This increase was regulated by Akt activation and NF-kappaB binding. p65 and p50-NF-kappaB are major transcriptional factors in the Mac-2BP promoter region, and were shown to be regulated in accordance with the Akt activation states. Collectively, these results suggest that NGF induces Mac-2BP expression via the PI3K/Akt/NF-kappaB pathway.

Biphenolic components in Magnolia obovata including magnolol and honokiol have shown several pharmacological activities such as anti-tumor, anti-oxidant and anti-inflammatory effects. Previously in cultured macrophage Raw264.7 cells and fibroblast, we found that obovatol, an active compound isolated from M. obovata inhibited NF-kappaB activity which has been known to be a significant transcriptional factor to control of cancer cell growth. We investigated here whether obovatol could inhibit NF-kappaB activity, and thereby inhibit cancer cell growth in prostate (LNCaP and PC-3) and colon cancer (SW620 and HCT116) cells. Treatment of obovatol (10, 15, 20, 25 microM) inhibits cancer cell growth in the absence or the presence of tumor necrosis factor-alpha (TNF-alpha , 10 ng/ml) and tetradecanoyl phorbol acetate (TPA 10 or 50 nM) in a concentration-dependent manner through induction of apoptotic cell death. Cytotoxic activity was not observed in normal cells with up to 50 muM obovatol. It was also found that obovatol inhibited TNF-alpha and TPA-induced transcriptional and DNA binding activities of NF-kappaB. In further study, obovatol decreased translocation p65 and p50 into nucleus via decrease of phosphorylation of IkappaB. Correlated well with the induction of apoptosis, obovatol increased the expression of the apoptotic genes; Bax, caspase-3, caspase-9, whereas inhibited expression of anti-apoptotic genes; Bcl-2, inhibitor of apoptosis protein (IAP-1) and X chromosome IAP (XIAP) as well as the cell proliferation marker genes; Cox-2, c-Fos, c-Jun and cyclin D1. These results suggest that obovatol inhibits prostate and colon cancer cell growth via induction of apoptotic cell death, and that inhibition of NF-kappaB may be a significant as its action mechanism.

Molecular mechanisms underlying epothilone-induced apoptotic cell death were investigated in SW620 human colon cancer cells. Treatment with epothilone B and D at different concentrations (1-100 nmol/L) dose-dependently inhibited cell growth and caused cell cycle arrest at G2-M, which was followed by apoptosis. Consistent with this induction of apoptotic cell death, epothilone B and D enhanced the constitutional activation of nuclear factor-kappaB (NF-kappaB) via IkappaB degradation through IkappaB kinase (IKKalpha and IKKbeta) activation, and this resulted in p50 and p65 translocation to the nucleus. Moreover, cells treated with sodium salicylic acid, an IKK inhibitor, or transiently transfected with mutant IKKalpha and beta did not show epothilone-induced cell growth inhibition or p50 translocation, although p65 was still translocated to the nucleus. Treatment with epothilone B and D also enhanced beta-tubulin polymerization and the formation of p50/beta-tubulin complex. However, beta-tubulin polymerization was not inhibited in the cells treated by sodium salicylic acid or transiently transfected with mutant IKKalpha and beta. Moreover, epothilone B and D increased the expressions of NF-kappaB-dependent apoptotic cell death regulatory genes, i.e., Bax, p53, and the active form of caspase-3, but reduced Bcl-2 expression, and these actions were partially reversed by salicylic acid. In addition, caspase-3 inhibitor reduced epothilone B-induced cell death and NF-kappaB activation. These findings suggest that the activation of NF-kappaB/IKK signals plays an important role in the epothilone-induced apoptotic cell death of SW620 colon cancer cells in a tubulin polymerization-independent manner.

Cobrotoxin is known to bind with cysteine residues of biological molecules such as nicotine acetylcholine receptor. Cobrotoxin may modify IKKs and p50 through protein-protein interaction since cysteine residues are present in the kinase domains of IKKalpha and IKKbeta and in the p50 of NF-kappaB. Our surface plasmon resonance analysis showed that cobrotoxin directly binds to p50 (K(d) = 1.54 x 10(-)(5) M), IKKalpha (K(d) = 3.94 x 10(-)(9) M) and IKKbeta (K(d) = 3.4 x 10(-)(8) M) with high binding affinity. Moreover, these protein-protein interactions suppressed the lipopolysaccharide (LPS, 1 microg/mL)- and the sodium nitroprusside (SNP, 200 microM)-induced DNA binding activity of NF-kappaB and NF-kappaB-dependent luciferase activity in astrocytes and Raw 264.7 macrophages. These inhibitory effects were correlated with the inhibition of IkappaB release and p50 translocation. Inhibition of NF-kappaB by cobrotoxin resulted in reductions in the LPS-induced expressions of COX-2, iNOS, cPLA(2), IL-4, and TNF-alpha in astrocytes and in COX-2 expression induced by SNP, LPS, and TNF-alpha in astrocytes. Moreover, these inhibitory effects of cobrotoxin were reversed by adding reducing agents, dithiothreitol and glutathione. In addition, cobrotoxin did not have any inhibitory effect on NF-kappaB activity in cells carrying mutant p50 (C62S), IKKalpha (C178A), and IKKbeta (C179A), with the exception of IKKbeta (K44A) mutant plasmid. Confocal microscopic analysis showed that cobrotoxin is uptaken into the nucleus of cells. These results demonstrate that cobrotoxin directly binds to the sulfhydryl groups of p50 and IKKs, and that this results in reduced IkappaB release and the translocation of p50, thereby inhibiting the activation of NF-kappaB.

Artemisia has been traditionally used in Korean herbal medicine to clear damp heat and to treat uteritis and jaundice. Flavonoids isolated from Artemisia are also known to possess anti-inflammatory activities. In this study, 5,6,3',5'-tetramethoxy 7,4'-hydroxyflavone (p7F) was isolated from Artemisia absinthium. We examined in vitro and in vivo regulatory functions of p7F on the production of nitric oxide (NO), prostaglandin E(2) (PGE(2)), and tumor necrosis factor-alpha (TNF-alpha) as well as the expression of inducible NO synthase (iNOS), cyclooxygenase-2 (COX-2), and collagen-induced arthritis. p7F inhibited the expression or production of proinflammatory mediators such as COX-2/PGE(2) and iNOS/NO in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. p7F also suppressed the serum level of TNF-alpha in mice treated with collagen and inhibited nuclear factor-kappaB (NF-kappaB) activation as well as NF-kappaB promoter activity in RAW 264.7 cells stimulated with LPS. This compound directly inhibited the intracellular accumulation of reactive oxygen species in hydrogen peroxide-stimulated RAW 264.7 cells. p7F has antioxidant activity and inhibits NF-kappaB activation. Taken together, these results suggest that p7F can be clinically applied to the treatment of inflammatory diseases.

Objective: To investigate the molecular mechanisms of the antiarthritic effects of bee venom (BV) and melittin (a major component of BV) in a murine macrophage cell line (Raw 264.7) and in synoviocytes obtained from patients with rheumatoid arthritis., Methods: We evaluated the antiarthritic effects of BV in a rat model of carrageenan-induced acute edema in the paw and in a rat model of chronic adjuvant-induced arthritis. The inhibitory effects of BV and melittin on inflammatory gene expression were measured by Western blotting, and the generation of prostaglandin E(2) (PGE(2)) and nitric oxide (NO) and the intracellular calcium level were assayed. NF-kappaB DNA binding and transcriptional activity were determined by gel mobility shift assay or by luciferase assay. Direct binding of BV and melittin to the p50 subunit of NF-kappaB was determined with a surface plasmon resonance analyzer., Results: BV (0.8 and 1.6 mug/kg) reduced the effects of carrageenan- and adjuvant-induced arthritis. This reducing effect was consistent with the inhibitory effects of BV (0.5, 1, and 5 mug/ml) and melittin (5 and 10 mug/ml) on lipopolysaccharide (LPS; 1 mug/ml)-induced expression of cyclooxygenase 2, cytosolic phospholipase A(2), inducible NO synthase, generation of PGE(2) and NO, and the intracellular calcium level. BV and melittin prevented LPS-induced transcriptional and DNA binding activity of NF-kappaB via the inhibition of IkappaB release and p50 translocation. BV (affinity [K(d)] = 4.6 x 10(-6)M) and melittin (K(d) = 1.2 x 10(-8)M) bound directly to p50., Conclusion: Target inactivation of NF-kappaB by directly binding to the p50 subunit is an important mechanism of the antiarthritic effects of BV.

Erythropoietin (EPO), a hematopoietic factor, is also required for normal brain development, and its receptor is localized in brain. Therefore, it is possible that EPO could act as a neurotropic factor inducing differentiation of neurons. In the present study, we investigated whether EPO can promote differentiation of neuronal stem cells into astrocytes. In primary culture of cortical neuronal stem cells isolated from post neonatal (Day 1) rat brain, EPO dose (0.1-10U/ml) dependently promoted initiation of morphological differentiation of astrocyte and expression of an astrocyte marker protein, glial fibrillary acidic protein (GFAP). Expression of EPO receptor was also increased during morphological differentiation of astrocytes. EPO-induced increased morphological differentiation of astrocytes and GFAP expression were reduced by treatment with anti-EPO and EPO receptor antibodies. Since our previous study showed that activation of MAPK family and transcription factors is differentially involved in neuronal cell differentiation, we further determined the activation of MAP kinase family and NF-kappaB during morphological differentiation of astrocytes. Concomitant with the progression of the morphological differentiation of astrocytes, ERK(2) but not JNK(1) and p38 MAPK as well as NF-kappaB were activated. However, in the presence of PD98,059, an inhibitor of ERK, and salicylic acid, an NF-kappaB inhibitor, the EPO-induced morphological differentiation of astrocytes and expression of FGAP and EPO receptor were reduced. Conversely, treatment with anti-EPO and EPO receptor antibodies also reduced EPO-induced ERK(2) and NF-kappaB activation. These data demonstrate that EPO can promote differentiation of neuronal stem cells into astrocytes in an EPO receptor dependent manner, and this effect may be associated with the activation of ERK kinase and NF-kappaB pathway.