• 한국식품영양과학회지
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• 제31권3호
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• pp.521-526
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• 2002

대두(백태,흑태)와 현미의 메탄올과 아세톤 추출물이 호르몬 의존형 유방암세포(MCF-7)와 호르몬 비의존형세포(MDA-MB-231)의 세포독성과 apoptosis에 미치는 영향을 살펴보았다 각 추출물별 25, 50, 100 ug/well의 농도로 24, 48, 72시간 배양 시 배양시간과 사용된 시료 모두 농도 의존적으로 유방암 세포생존율을 억제하는 것으로 나타났다. 특히 호르몬 의존형 세포인 MCF-7 에서는 현미의 아세톤 추출물이 낮은 농도에서 짧은 배양시간에도 그 효과가 나타났고 호르몬 비의존형 세포주 MDA-MB-231에서는 현미의 아세톤 및 메탄올 추출물의 효과가 다른 시료들에 비해 높게 나타났다. Apoptosis에 미치는 영향에서는 호르몬 비의존형 세포(MDA-MB-231)에서 메탄올추출물 처리군이 대조군에 비해 apoptosis된 세포가 유의적으로 증가한 것을 관찰할 수 있었다. 그러나 세포생존율 결과와는 다르게 호르몬의존형 세포와 호르몬비의존형 세포 모두에서 아세톤 처리군은 대조군에 비해 apptosis에 유의차를 나타내지 않았다. 이상의 결과에 의하면 이들 화합물이 소유한 암세포 성장억제 기전은 추출물내 함유된 화합물의 종류와 세포성장의 호르몬 의존도에 따라 다양한 것으로 사료된다.

• Journal of Microbiology and Biotechnology
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• 제21권5호
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• pp.540-544
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• 2011

The molecular mechanisms of apoptotic induction by benzyldihydroxyoctenone (BDH), a nonsteroidal antiandrogen, isolated from the culture broth of Streptomyces sp., have been previously published in prostate cancer LNCaP cells. Apoptotic induction of BDH-treated LNCaP cells was associated with downregulation of Bcl-xL that caused, in turn, cytochrome c release from mitochondria, and activation of procaspases and specific proteolytic cleavage of poly(ADP-ribose) polymerase (PARP). The purpose of the present study was to investigate the patterns of apoptotic induction by BDH in non-prostate, ovarian cancer PA-1 (androgen-independent and -insensitive) cells and prostate cancer cells with different androgen responsiveness, such as C4-2 (androgen-independent and -sensitive), 22Rv1 (androgen-dependent and -low sensitive), and LNCaP (androgen-dependent and -high sensitive) cells. We found that BDH-treated LNCaP cell proliferation was significantly inhibited in a time-dependent manner and induced apoptosis via downregulation of the androgen receptor (AR) and prostate-specific antigen (PSA), as well as antiapoptotic Bcl-xL protein. However, the levels of BDH-mediated apoptotic induction and growth inhibition in 22Rv1 cells were apparently lower than those of LNCaP cells. In contrast, the induction of apoptosis and antiproliferative effect in BDH-treated non-prostate cancer PA-1 and hormone refractory C4-2 cells were not detectable and marginal, respectively. Therefore, BDH-mediated differential apoptotic induction and growth inhibition in a cell type seem to be obviously dependent on its androgen responsiveness; primarily on androgen-dependency, and then on androgensensitivity.

• 대한의생명과학회지
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• 제24권3호
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• pp.143-149
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• 2018

Excessive exposure to estrogens is the most important risk factor for the development of hormone-sensitive cancers, especially breast cancer. Estrogen stimulates the expression of genes and proteins involved in cell proliferation by binding to estrogen receptor (ER). Another possible mechanism of ER-independent carcinogenicity of estrogens is based on the hydroxylation of estradiol resulting in the formation of catechol estrogens. Catechol estrogen 4-hydroxyestradiol ($4-OHE_2$) is further oxidized to catechol estrogen-3,4-quinones, the major carcinogenic metabolites of estrogens. Evidence increasingly supports the critical role of $4-OHE_2$ in hormonal carcinogenesis via DNA adduct formation or production of reactive oxygen species, which finally contribute to the transformation of normal mammary epithelial cells and the enhanced growth of breast cancer cells. It is also reported that the level of $4-OHE_2$ or its quinones is highly up-regulated in urine or tissues of breast cancer patients. Thus, we highlight the oncogenic roles of $4-OHE_2$ in catechol estrogen-induced breast carcinogenesis.

• Molecules and Cells
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• 제46권11호
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• pp.710-724
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• 2023

The plant defense responses to microbial infection are tightly regulated and integrated with the developmental program for optimal resources allocation. Notably, the defense-associated hormone salicylic acid (SA) acts as a promoter of flowering while several plant pathogens actively target the flowering signaling pathway to promote their virulence or dissemination. Ralstonia pseudosolanacearum inject tens of effectors in the host cells that collectively promote bacterial proliferation in plant tissues. Here, we characterized the function of the broadly conserved R. pseudosolanacearum effector RipL, through heterologous expression in Arabidopsis thaliana. RipL-expressing transgenic lines presented a delayed flowering, which correlated with a low expression of flowering regulator genes. Delayed flowering was also observed in Nicotiana benthamiana plants transiently expressing RipL. In parallel, RipL promoted plant susceptibility to virulent strains of Pseudomonas syringae in the effector-expressing lines or when delivered by the type III secretion system. Unexpectedly, SA accumulation and SA-dependent immune signaling were not significantly affected by RipL expression. Rather, the RNA-seq analysis of infected RipL-expressing lines revealed that the overall amplitude of the transcriptional response was dampened, suggesting that RipL could promote plant susceptibility in an SA-independent manner. Further elucidation of the molecular mechanisms underpinning RipL effect on flowering and immunity may reveal novel effector functions in host cells.

• International Journal of Oral Biology
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• 제33권3호
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• pp.113-116
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• 2008

Cementum is the mineralized tissue of the tooth. It is similar to bone in several aspects but it differs from bone. Human bone marrow stromal cells (BMSC) and human cementum derived cells (HCDC) (10,000 $cells/cm^2$) were plated in 6 well plates as feeder cells. The next day, mouse bone marrow cells (1.5 million $cells/cm^2$) were added. One group of these plates were incubated in serum-free conditioned medium (SFCM) generated from BMSC or HCDC supplemented with 2% FBS, parathyroid hormone (PTH), 1, 25 dihydroxyvitamin $D_3$ (Vit. $D_3$) and dexamethasone, or plain medium with the same supplements. Another group of plates were cocultured with BMSC or HCDC in plain medium supplemented with 2% FBS, PTH, Vit. $D_3$ and dexamethasone. Plates grown without SFCM or coculture were used as controls. After 10 days, the cells were stained for tartrate-resistant acid phosphatase (TRAP). BMSC were found to support osteoclast formation under normal conditions. This was inhibited however by both SFCM generated from HCDC and also by coculture with HCDC. In addition, HCDC themselves did not support osteoclast formation under any conditions. Our results thus indicate that HCDC do not support osteoclast formation in vitro and that soluble factor (s) from HCDC may inhibit this process. In addition, we show that this inhibition also involves an active mechanism that is independent of osteoprotegerin, a feature that may distinguish cementoblasts from other cells present in periodontium.

• Asian Pacific Journal of Cancer Prevention
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• 제16권14호
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• pp.5703-5707
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• 2015

Background: Medicinal plants, especially examples rich in polyphenolic compounds, have been suggested to be chemopreventive on account of their antioxidative properties. Melissa officinalis L. (MO), an aromatic and medicinal plant, is well known in thios context. However, toxicity against cancer cells has not been fully studied. Here, we investigated the selective anticancer effects of an MO extract (MOE) in different human cancer cells. Materials and Methods: a hydro-alcoholic extract of MO was prepared and total phenolic content (TPC) and total flavonoid content (TFC) were determined by colorimetric assays. Antioxidant activity was determined by DPPH radical scavenging activity. MTT assays were used to evaluate cytotoxicity of different doses of MOE (0, 5, 20, 100, 250, 500, $1000{\mu}g/ml$) towards A549 (lung non small cell cancer cells), MCF-7 (breast adenocarcinoma), SKOV3 (ovarian cancer cells), and PC-3 (prostate adenocarcinoma) cells. Results: Significant (P<0.01) or very significant (P<0.0001) differences were observed in comparison to negative controls at all tested doses ($5-1000{\mu}g/ml$). In all cancer cells, MOE reduced the cell viability to values below 33%, even at the lowest doses. In all cases, $IC_{50}$ values were below $5{\mu}g/ml$. The mean growth inhibition was 73.1%, 86.7%, 79.9% and 77.8% in SKOV3, MCF-7 and PC-3 and A549 cells, respectively. Conclusions: Our results indicate that a hydro-alcoholic extract of MO possess a high potency to inhibit proliferation of different tumor cells in a dose independent manner, suggesting that an optimal biological dose is more important than a maximally tolerated one. Moreover, the antiprolifreative effect of MO seems to be tumor type specific, as hormone dependant cancers were more sensitive to antitumoral effects of MOE.

• Molecules and Cells
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• 제41권4호
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• pp.311-319
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• 2018

The gaseous hormone ethylene influences many aspects of plant growth, development, and responses to a variety of stresses. The biosynthesis of ethylene is tightly regulated by various internal and external stimuli, and the primary target of the regulation is the enzyme 1-aminocyclopropane-1-carboxylic acid (ACC) synthase (ACS), which catalyzes the rate-limiting step of ethylene biosynthesis. We have previously demonstrated that the regulation of ethylene biosynthesis is a common feature of most of the phytohormones in etiolated Arabidopsis seedlings via the modulation of the protein stability of ACS. Here, we show that various phytohormones also regulate ethylene biosynthesis from etiolated rice seedlings in a similar manner to those in Arabidopsis. Cytokinin, brassinosteroids, and gibberellic acid increase ethylene biosynthesis without changing the transcript levels of neither OsACS nor ACC oxidases (OsACO), a family of enzymes catalyzing the final step of the ethylene biosynthetic pathway. Likewise, salicylic acid and abscisic acid do not alter the gene expression of OsACS, but both hormones downregulate the transcript levels of a subset of ACO genes, resulting in a decrease in ethylene biosynthesis. In addition, we show that the treatment of the phytohormones results in distinct etiolated seedling phenotypes, some of which resemble ethylene-responsive phenotypes, while others display ethylene-independent morphologies, indicating a complicated hormone crosstalk in rice. Together, our study brings a new insight into crosstalk between ethylene biosynthesis and other phytohormones, and provides evidence that rice ethylene biosynthesis could be regulated by the post-transcriptional regulation of ACS proteins.

• 한국발생생물학회:학술대회논문집
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• 한국발생생물학회 2003년도 제3회 국제심포지움 및 학술대회
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• pp.83-83
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• 2003

The lutropin/choriogonadotropin receptor (LHR) is a member of the rhodopsin-like subfamily of G protein coupled receptor (GPCRs), that has been shown to mediate the internalization of its two naturally occurring agonist, lutropin and choriogonadotropin (CG). The clustered agonist-receptor complex is internalized by a dynamin-dependent pathway and traverses the endosomal compartment without agonist dissociation Dissociation of the agonist-receptor complex occurs in the lysosomes, where both the agonist and receptor are degrade. Recently, constitutively activating mutations of the receptor have been identified that are associated with familial male-precocious puberty (FMPP). A FMPP is a form of sexual precocious puberty in boys in which testosterone levels are elevated independent of changes in luteinizing hormone-releasing hormone and serum luteinizing hormone levels, We have now analyzed two naturally occurring, constitutively active mutants of the human LHR. These mutations were introduced into the rat LHR (rLHR) and are designated L435R and D556Y. Cells expressing rLHR-D556Y bind human choriogonadotropin (hCG) with normal affinity, exhibit a 25-fold increase in basal cAMP and respond to hCG with a normal increase in cAMP accumulation. Cells expressing rLHR-L435R also bind hCG with normal affinity, exhibit a 47-fold increase in basal cAMP, and do not respond to hCG with a further increase in cAMP accumulation. This mutation enhances the internalization of the free and agonist-occupied receptors ~2- and ~17- fold, respectively We conclude that the state of activation of the rLHR can modulate its basal and/or agonist-stimulated internalization. Since the internalization of hCG is involved in the termination of hCG actions, we suggest that the lack of responsiveness detected in cells expressing rLHR-L435R is due to the fast rate of internalization of the bound hCG. The finding that membranes expressing rLHR-L435R respond to hCG with an increase in adenylyl cyclase activity supports this suggestion. Autonomous Leydig cell activity in FMPP is caused by a constitutively activating LH/CGR.

• Journal of Yeungnam Medical Science
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• 제20권2호
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• pp.129-141
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• 2003

Background: Leptin is a 16-KDa non-glycosylated peptide hormone synthesized almost exclusively by adipocytes. The well-known function of leptin is regulation of food intake and energy expenditure. Leptin also plays a regulatory role in immune and inflammatory process including cytokine production. The purpose of this study was to investigate the effect of leptin on the expression of several chemokine genes(RANTES, IL-8, MCP-1, IP-10, Mig, MIP-$1{\alpha}$, MIP-$1{\beta}$, and GRO-${\alpha}$) in THP-1 cells. Materials and Methods: Total RNA of THP-1 cells were prepared by Trizol method, and then stimulated with the leptin(250 ng/$m{\ell}$) or LPS(100 ng/$m{\ell}$). We examined the expression patterns of various chemokine mRNAs in THP-1 cell lines by RT-PCR and Northern blot. Results: Leptin did not induce the expression of chemokine mRNAs in THP-1 cells. The expression patterns of RANTES, IL-8, MCP-1, IP-10, and Mig mRNAs in THP-1 cells stimulated with leptin and LPS simultaneously was almost same to the patterns of LPS alone-induced chemokine mRNAs. RANTES mRNA expression was independent on the concentrations of leptin. Although leptin did not have strong effect on the expression of RANTES, IL-8, MCP-1, IP-10, Mig, MIP-$1{\alpha}$, MIP-$1{\beta}$, and GRO-${\alpha}$ mRNAs in THP-1 cells, leptin could induce the expression of long isoform of leptin receptor(OB-RL) mRNA, and its expression was elevated in simultaneous stimulation of leptin and LPS. Conclusion: These data suggest that leptin is able to induce OB-RL in THP-1 cells, however, leptin has little effect on the expression of pro-inflammatory chemokine genes.

• 대한의생명과학회지
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• 제25권4호
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• pp.417-425
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• 2019

Cadmium (Cd) generates reactive oxygen species (ROS), which in turn cause the apoptosis of various cell types including developing germ cells in rodent testis. Ascorbic acids (AA), one of the ROS scavengers, had been reported to protect against Cd-induced apoptosis. N-Acetyl-L-cysteine (NAC), another ROS scavenger, is known to remove ROS and alleviate the Cd-induced apoptosis in various cell types. In this study we tried to elucidate how NAC affected on Cd-induced cell apoptosis in rat testis. Rats were administered with NAC before and after Cd treatment and then testicular cell apoptosis was examined. NAC treatment resulted in the reduction of Cd-induced chromosomal DNA fragmentation in agarose gel electrophoresis. Terminal deoxynucleotidyl transferase dUTP nick end-labeling (TUNEL) assay showed that treatment of NAC reduced the Cd-induced apoptosis of germ cells. The administration of NAC showed that the translocation of apoptosis inducing factor (AIF) from mitochondria to nucleus was prevented, which indicated that the mechanism of Cd-induced testicular apoptosis is mediated through the release of AIF in caspase-independent manner. Taken together, the NAC may remove Cd-induced ROS and protect ROS-induced cell apoptosis in rat testis.