Resveratrol Inhibits IL-6-Induced Transcriptional Activity of AR and STAT3 in Human Prostate Cancer LNCaP-FGC Cells

( Mee Hyun Lee ),( Joydeb Kumar Kundu ),( Young Sam Keum ),( Yong Yeon Cho ),( Young Joon Surh ),( Bu Young Choi ) 한국응용약물학회 2014 Biomolecules & Therapeutics(구 응용약물학회지) Vol.22 No.5

Prostate cancer is the most frequently diagnosed cancer. Although prostate tumors respond to androgen ablation therapy at an early stage, they often acquire the potential of androgen-independent growth. Elevated transcriptional activity of androgen receptor (AR) and/or signal transducer and activator of transcription-3 (STAT3) contributes to the proliferation of prostate cancer cells. In the present study, we examined the effect of resveratrol, a phytoalexin present in grapes, on the reporter gene activity of AR and STAT3 in human prostate cancer (LNCaP-FGC) cells stimulated with interleukin-6 (IL-6) and/or dihydrotestosterone (DHT). Our study revealed that resveratrol suppressed the growth of LNCaP-FGC cells in a time- and concentration-dependent manner. Whereas the AR transcriptional activity was induced by treatment with either IL-6 or DHT, the STAT3 transcriptional activity was induced only by treatment with IL-6 but not with DHT. Resveratrol significantly attenuated IL-6-induced STAT3 transcriptional activity, and DHT- or IL-6-induced AR transcriptional activity. Treatment of cells with DHT plus IL-6 significantly increased the AR transcriptional activity as compared to DHT or IL-6 treatment alone and resveratrol markedly diminished DHT plus IL-6-induced AR transcriptional activity. Furthermore, the production of prostate-specific antigen (PSA) was decreased by resveratrol in the DHT-, IL-6- or DHT plus IL-6-treated LNCaP-FGC cells. Taken together, the inhibitory effects of resveratrol on IL-6- and/or DHTinduced AR transcriptional activity in LNCaP prostate cancer cells are partly mediated through the suppression of STAT3 reporter gene activity, suggesting that resveratrol may be a promising therapeutic choice for the treatment of prostate cancer.

Interaction of promyelocytic leukemia/p53 affects signal transducer and activator of transcription-3 activity in response to oncostatin M

Jiwoo Lim,Ji Ha Choi,Eun-Mi Park,Youn-Hee Choi 대한생리학회-대한약리학회 2020 The Korean Journal of Physiology & Pharmacology Vol.24 No.3

Promyelocytic leukemia (PML) gene, through alternative splicing of its Cterminal region, generates several PML isoforms that interact with specific partners and perform distinct functions. The PML protein is a tumor suppressor that plays an important role by interacting with various proteins. Herein, we investigated the effect of the PML isoforms on oncostatin M (OSM)-induced signal transducer and activator of transcription-3 (STAT-3) transcriptional activity. PML influenced OSMinduced STAT-3 activity in a cell type-specific manner, which was dependent on the p53 status of the cells but regardless of PML isoform. Interestingly, overexpression of PML exerted opposite effects on OSM-induced STAT-3 activity in p53 wild-type and mutant cells. Specifically, overexpression of PML in the cell lines bearing wild-type p53 (NIH3T3 and U87-MG cells) decreased OSM-induced STAT-3 transcriptional activity, whereas overexpression of PML increased OSM-induced STAT-3 transcriptional activity in mutant p53-bearing cell lines (HEK293T and U251-MG cells). When wild-type p53 cells were co-transfected with PML-IV and R273H-p53 mutant, OSM-mediated STAT-3 transcriptional activity was significantly enhanced, compared to that of cells which were transfected with PML-IV alone; however, when cells bearing mutant p53 were co-transfected with PML-IV and wild-type p53, OSM-induced STAT-3 transcriptional activity was significantly decreased, compared to that of transfected cells with PML-IV alone. In conclusion, PML acts together with wild-type or mutant p53 and influences OSM-mediated STAT-3 activity in a negative or positive manner, resulting in the aberrant activation of STAT-3 in cancer cells bearing mutant p53 probably might occur through the interaction of mutant p53 with PML.

Chromatin Kinases Act on Transcription Factors and Histone Tails in Regulation of Inducible Transcription

Josefowicz, Steven Z.,Shimada, M.,Armache, A.,Li, Charles H.,Miller, Rand M.,Lin, S.,Yang, A.,Dill, Brian D.,Molina, H.,Park, H.S.,Garcia, Benjamin A.,Taunton, J.,Roeder, Robert G.,Allis, C. Cell Press 2016 Molecular cell Vol.64 No.2

<P>The inflammatory response requires coordinated activation of both transcription factors and chromatin to induce transcription for defense against pathogens and environmental insults. We sought to elucidate the connections between inflammatory signaling pathways and chromatin through genomic footprinting of kinase activity and unbiased identification of prominent histone phosphorylation events. We identified H3 serine 28 phosphorylation (H3S28ph) as the principal stimulation-dependent histone modification and observed its enrichment at induced genes in mouse macrophages stimulated with bacterial lipopolysaccharide. Using pharmacological and genetic approaches, we identified mitogen-and stress-activated protein kinases (MSKs) as primary mediators of H3S28ph in macrophages. Cell-free transcription assays demonstrated that H3S28ph directly promotes p300/CBP-dependent transcription. Further, MSKs can activate both signal-responsive transcription factors and the chromatin template with additive effects on transcription. Specific inhibition of MSKs in macrophages selectively reduced transcription of stimulation-induced genes. Our results suggest that MSKs incorporate upstream signaling inputs and control multiple downstream regulators of inducible transcription.</P>

The Nuclear Matrix Protein, NRP/B, Acts as a Transcriptional Repressor of E2F-mediated Transcriptional Activity

Jina Choi,Eun Sung Yang,Kiweon Cha,John Whang,Woo-Jung Choi,Shalom Avraham,김태억 대한암예방학회 2014 Journal of cancer prevention Vol.19 No.3

Background: NRP/B, a family member of the BTB/Kelch repeat proteins, is implicated in neuronal and cancer development, as well as the regulation of oxidative stress responses in breast and brain cancer. Our previous studies indicate that the NRP/B-BTB/POZ domain is involved in the dimerization of NRP/B and in a complex formation with the tumor suppressor, retinoblastoma protein. Although much evidence supports the potential role of NRP/B as a tumor suppressor, the molecular mechanisms of NRP/B action on E2F transcription factors have not been elucidated. Methods: Three-dimensional modeling of NRP/B was used to generate point mutations in the BTB/Kelch domains. Tet-on inducible NRP/B expression was established. The NRP/B deficient breast cancer cell line, MDA-MB-231, was generated using lentiviral shNRP/B to evaluate the effect of NRP/B on cell proliferation, invasion and migration. Immunoprecipitation was performed to verify the interaction of NRP/B with E2F and histone deacetylase (HDAC-1), and the expression level of NRP/B protein was analyzed by Western blot analysis.Changes in cell cycle were determined by flow cytometry. Transcriptional activities of E2F transcription factors were measured by chloramphenicol acetyltransferase (CAT) activity. Results: Ectopic overexpression of NRP/B demonstrated that the NRP/B-BTB/POZ domain plays a critical role in E2F-mediated transcriptional activity. Point mutations within the BTB/POZ domain restored E2-promoter activity inhibited by NRP/B. Loss of NRP/B enhanced the proliferation and migration of breast cancer cells. Endogenous NRP/B interacted with E2F and HDAC1. Treatement with an HDAC inhibitor, trichostatin A (TSA), abolished the NRP/B-mediated suppression of E2-promoter activity. Gain or loss of NRP/B in HeLa cells confirmed the transcriptional repressive capability of NRP/B on the E2F target genes, Cyclin E and HsORC (Homo sapiens Origin Recognition Complex). Conclusions: The present study shows that NRP/B acts as a transcriptional repressor by interacting with the co-repressors, HDAC1, providing new insight into the molecular mechanisms of NRP/B on tumor suppression.

각질형성세포에서 Chrysin이 Vitamin D Receptor의 전사 활성화에 미치는 영향

추정하 ( Jung Ha Choo ),이상화 ( Sang Hwa Lee ) 대한화장품학회 2013 대한화장품학회지 Vol.39 No.1

Chrysin (5,7-dihydroxyflavone)은 프로폴리스, 꿀 같은 음식과 다양한 식물에 존재하는 천연 플라보노이드이다. Chrysin은 항산화, 항노화, 항염, 항암 효과 등 다양한 생물학적 효과를 가진다고 알려져 있다. 이 연구에서, 우리는 사람의 각질형성세포에서 chrysin이 VDR을 통한 transcriptional activity에 미치는 영향을 dual-luciferase assay을 통하여 살펴보았다. Chrysin은 농도 의존적으로 VDR을 통한 transcriptional activity를 증가시켰다. Quantitative real time PCR을 통해 chrysin이 사람의 각질형성세포에서 VDR mRNA의 발현을 증가시킴을 확인하였다. 또한, chrysin이 각질형성세포의 분화 마커인 keratin 10, involucrin 그리고 filaggrin의 mRNA 발현을 증가시킴을 확인하였다. 이러한 연구 결과는 chrysin이 VDR을 통한 transcriptional activity를 조절하여 각질형성세포의 분화를 촉진시킬 수 있다는 것을 시사한다. Chrysin (5,7-dihydroxyflavone) is a natural flavonoid found in various plants and foods such as propolis and honey. It has been reported that chrysin has various biological effects including antioxidant, anti-aging, anti-inflammatory and anti-cancer. In this study, we investigated the effect of chrysin on the transcriptional activity of VDR in human epidermal keratinocytes by performing dual-luciferase assay. Chrysin significantly induced the transcriptional activity of VDR in a concentration-dependent manner. The VDR mRNA expression was investigated by quantitative real time PCR and chrysin increased the VDR mRNA expression in normal human epidermal keratinocytes. We also found that chrysin increased the expression of keratinocyte differentiation markers such as keratin 10, involucrin and filaggrin. Therefore, the results suggest that chrysin can stimulate the differentiation of human keratinocytes by increasing transcriptional activity of VDR.

렙틴 수용체가 형질 도입된 신경세포에서 ER Stress로 유도된 렙틴저항성에 대한 일산화탄소의 억제작용

김성주,김택상,류현열,정헌택 고신대학교 의과대학 2010 고신대학교 의과대학 학술지 Vol.25 No.1

연구 배경 및 목적: 렙틴이 음식의 섭취 양과 체중의 증가를 억제하는 중요한 호르몬 역할을 한다는 사실은 잘 알려졌다. 또한 렙틴에 대한 저항성이 비만의 중요한 원인이라는 연구가 많이 보고되고 있다. 그러나 렙틴 저항성에 대한 구체적인 기전은 아직 밝혀져 있지 않았다. 최근 endoplasmic reticulum (ER) 스트레스에 의한 unfolded protein response (UPR) 가 렙틴에 대한 저항성을 유발한 다는 보고가 있었다. 연구 대상 및 방법: 일산화탄소(carbon monoxide, CO)는 heme oxygenase (HO)-1이 헴(heme)을 산화적 분해로 만들어내는 무색, 무미, 무취의 기체로 항산화, 항염증, 항세포분열 및 항세포고사 작용을 나타내며 조직의 손상에 대한 세포보호작용을 한다. 최근 CO는 ER stress sensor 중의 하나인 protein kinase R-like endoplasmic reticulum kinase (PERK) 를 선택적으로 활성화 시키며 인산화된 PERK 는 HO-1의 전사조절인자인 Nrf2를 인산화로 활성화시켜 결국 HO-1의 유전자 발현을 촉진함이 보고 되였다. 또한 CO로 유도된 PERK의 활성화는 eukaryotic translation initiation factor (eIF) 2a를 인산화로 활성화 시키고 인산화된 eIF2a는 전사인자인 activating transcription factor (ATF)-4의 발현을 유도하지만 CO는 ER stress의 다른 두 개 sensors인 inositol requiring enzyme (IRE) 1a와 하위신호전단물질인 X-box binding protein (xbp)-1이나 ATF6의 활성화에는 영향을 미치지 아니한다. 그러나 ER stress 유발인자들인 thasigargin (TG), tunicamycin (TM), homocysteine 등으로 Xbp-1이나 ATF6가 활성화되는 것을 억제한다. 연구 결과: 본 연구에서는 ER stress 에 의해 활성화되는 UPR에 의해 유발되는 렙틴 저항성이 CO에 의하여 차단될 것이라는 가정을 세우고 다음과 같은 실험결과를 얻었다. TG나 TM에 의해 유도된 ER stress반응 즉 UPR은 렙틴의 신호전달로 야기되는 phospho-signal transducer and activation of transcription (STAT) 3로 인산화되는것을 억제시켰다. 그러나 ER stress를 유도시킬 시 CO를 CO releasing molecule (CORM)으로 처리하였을 때 UPR에 의한 렙틴의 신호전달로 말미암는 STAT3 인산화의 차단이 CO의 양과 노출 시간에 비례하여 제거 되었다. 결론: 이러한 실험결과는 CO에 의한 PERK 인산화는 ER stress 유도체에 의한 IRE1a의 하위 신호전달물질인 Xbp-1 이나 ATF6의 활성화를 억제하여 ER stress 반응인 UPR에 의한 렙틴 저항성을 차단함을 시사한다. 결론적으로 이러한 실험결과는 CO유도체를 이용하여 병인적인 렙틴 저항에 의한 여러 질병을 치료할 수 있음을 시사한다. Background: It is well known that leptin is an important circulating signal for the inhibition of food intake and the gain of body weight. Accumulating data suggest that leptin resistance has been considered to be one of the main causes of obesity. However, the detailed mechanism of leptin resistance is not known yet. Recently, endoplasmic reticulum (ER) stress-induced unfolded protein response (UPR) is reported to be responsible for the leptin resistance. Materials & methods: Carbon monoxide (CO), a reaction product of the cytoprotective heme oxygenase (HO)-1, is anti-apoptotic in a variety of models of cellular injury. Exogenous CO activated Nrf2 through the phosphorylation of protein kinase R-like endoplasmic reticulum kinase (PERK), resulting in HO-1 expression. CO-induced activation of PERK was followed by the phosphorylation of eukaryotic translation initiation factor 2a and the expression of activating transcription factor 4. However, CO fails to induce X-box binding protein-1 expression and activating transcription factor 6 cleavage. CO prevented X-box binding protein-1 expression and activating transcription factor 6 cleavage induced by ER-stress inducer such as thasigargin (TG), tunicamycin (TM) and homocysteine. Results: In the present study, we hypothesized that exogenous CO might block the leptin resistance which is induced by UPR during ER stress. Thasigargin or tunicamycin was used to induce ER stress. The activation status of leptin signals were measured by western blotting analysis using a phospho-signal transducer and activation of transcription3 (STAT3) antibody. In this study, ER stress markedly inhibited leptin-induced STAT3 phosphorylation. Conculusion: These results suggest that ER stress induces leptin resistance and exogenous CO-induced phosphorylation of PERK branch reversed ER stress-induced leptin resistance. Moreover, CO releasing molecule (CORM) blocks the inhibition of leptin-induced STAT3 phosphorylation. Together, the pathological mechanism of leptin resistance could be ameliorated by the use of exogenous CO..

The Dietary Compounds Resveratrol and Genistein Induce Activating Transcription Factor 3 While Suppressing Inhibitor of DNA Binding/Differentiation-1

Frank G. Bottone Jr.,Brenda Alston-Mills 한국식품영양과학회 2011 Journal of medicinal food Vol.14 No.6

Various chemopreventive compounds alter gene expression, possibly explaining their biological activity. One gene induced by a variety of chemopreventive compounds is the one coding for the transcription factor activating transcription factor 3 (ATF3). In this study, we performed microarray analysis on mRNA isolated from human colorectal cancer cells overexpressing ATF3 to ascertain the biological activity of this gene in cancer. As a result, 64 genes were induced or repressed. One gene identified by microarray analysis as repressed by overexpression of ATF3 was inhibitor of DNA binding/differentiation-1 (Id1). Id1 is important to cell growth and proliferation and therefore may represent an important downstream target of ATF3 responsible for the biological activity of ATF3. Id1 interacts with ATF3, thereby sequestering its activity, making it an ideal candidate for further study. The induction of ATF3 and repression of Id1 in these cells were confirmed at the mRNA and protein levels by semiquantitative real-time reverse transcription–polymerase chain reaction and western blot analysis, respectively. To determine if the repression of Id1 seen following microarray analysis of these cells occurred following treatment with dietary compounds with known chemotherapeutic activity, human colorectal cancer cells were treated with resveratrol and genistein, and their expression was determined. As a result, ATF3 was induced, and Id1 was repressed, by these compounds and by sulindac sulfide, a positive control, at the mRNA and protein level. Further work is needed to determine the molecular mechanism(s) responsible for the regulation of Id1 and to determine if biological activity of ATF3 overexpression is mediated by repression of Id1 by these compounds.

Kahweol from Coffee Induces Apoptosis by Upregulating Activating Transcription Factor 3 in Human Colorectal Cancer Cells

( Gwang Hun Park ),( Hun Min Song ),( Jin Boo Jeong ) 한국응용약물학회 2017 Biomolecules & Therapeutics(구 응용약물학회지) Vol.25 No.3

Kahweol as a coffee-specific diterpene has been reported to induce apoptosis in human cancer cells. Although some molecular targets for kahweol-mediated apoptosis have been elucidated, the further mechanism for apoptotic effect of kahweol is not known. Activating transcription factor 3 (ATF3) has been reported to be associated with apoptosis in colorectal cancer. The present study was performed to investigate the molecular mechanism by which kahweol stimulates ATF3 expression and apoptosis in human colorectal cancer cells. Kahweol increased apoptosis in human colorectal cancer cells. It also increased ATF3 expression through the transcriptional activity. The responsible cis-element for ATF3 transcriptional activation by kahweol was CREB located between -147 to -85 of ATF3 promoter. ATF3 overexpression increased kahweol-mediated cleaved PARP, while ATF3 knockdown attenuated the cleavage of PARP by kahweol. Inhibition of ERK1/2 and GSK3β blocked kahweol-mediated ATF3 expression. The results suggest that kahweol induces apoptosis through ATF3-mediated pathway in human colorectal cancer cells.

Molecular mechanism of protopanaxadiol saponin fraction-mediated anti-inflammatory actions

Yang, Yanyan,Lee, Jongsung,Rhee, Man Hee,Yu, Tao,Baek, Kwang-Soo,Sung, Nak Yoon,Kim, Yong,Yoon, Keejung,Kim, Ji Hye,Kwak, Yi-Seong,Hong, Sungyoul,Kim, Jong-Hoon,Cho, Jae Youl The Korean Society of Ginseng 2015 Journal of Ginseng Research Vol.39 No.1

Background: Korean Red Ginseng (KRG) is a representative traditional herbal medicine with many different pharmacological properties including anticancer, anti-atherosclerosis, anti-diabetes, and anti-inflammatory activities. Only a few studies have explored the molecular mechanism of KRG-mediated anti-inflammatory activity. Methods: We investigated the anti-inflammatory mechanisms of the protopanaxadiol saponin fraction (PPD-SF) of KRG using in vitro and in vivo inflammatory models. Results: PPD-SF dose-dependently diminished the release of inflammatory mediators [nitric oxide (NO), tumor necrosis factor-${\alpha}$, and prostaglandin $E_2$], and downregulated the mRNA expression of their corresponding genes (inducible NO synthase, tumor necrosis factor-${\alpha}$, and cyclooxygenase-2), without altering cell viability. The PPD-SF-mediated suppression of these events appeared to be regulated by a blockade of p38, c-Jun N-terminal kinase (JNK), and TANK (TRAF family member-associated NF-kappa-B activator)-binding kinase 1 (TBK1), which are linked to the activation of activating transcription factor 2 (ATF2) and interferon regulatory transcription factor 3 (IRF3). Moreover, this fraction also ameliorated HCl/ethanol/-induced gastritis via suppression of phospho-JNK2 levels. Conclusion: These results strongly suggest that the anti-inflammatory action of PPD-SF could be mediated by a reduction in the activation of p38-, JNK2-, and TANK-binding-kinase-1-linked pathways and their corresponding transcription factors (ATF2 and IRF3).

Molecular mechanism of protopanaxadiol saponin fraction-mediated anti-inflammatory actions

Yanyan Yang,이종성,이만휘,Tao Yu,백광수,성낙윤,김용,윤기정,Ji Hye Kim,Yi-Seong Kwak,Sungyoul Hong,김종훈,조재열 고려인삼학회 2015 Journal of Ginseng Research Vol.39 No.1

Background: Korean Red Ginseng (KRG) is a representative traditional herbal medicine with manydifferent pharmacological properties including anticancer, anti-atherosclerosis, anti-diabetes, and antiinflammatoryactivities. Only a few studies have explored the molecular mechanism of KRG-mediatedanti-inflammatory activity. Methods: We investigated the anti-inflammatory mechanisms of the protopanaxadiol saponin fraction(PPD-SF) of KRG using in vitro and in vivo inflammatory models. Results: PPD-SF dose-dependently diminished the release of inflammatory mediators [nitric oxide (NO),tumor necrosis factor-a, and prostaglandin E2], and downregulated the mRNA expression of their correspondinggenes (inducible NO synthase, tumor necrosis factor-a, and cyclooxygenase-2), withoutaltering cell viability. The PPD-SF-mediated suppression of these events appeared to be regulated by ablockade of p38, c-Jun N-terminal kinase (JNK), and TANK (TRAF family member-associated NF-kappa-Bactivator)-binding kinase 1 (TBK1), which are linked to the activation of activating transcription factor 2(ATF2) and interferon regulatory transcription factor 3 (IRF3). Moreover, this fraction also amelioratedHCl/ethanol/-induced gastritis via suppression of phospho-JNK2 levels. Conclusion: These results strongly suggest that the anti-inflammatory action of PPD-SF could be mediatedby a reduction in the activation of p38-, JNK2-, and TANK-binding-kinase-1-linked pathways andtheir corresponding transcription factors (ATF2 and IRF3).