• Biomolecules & Therapeutics
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• 제26권1호
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• pp.4-9
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• 2018

Cancer metabolism as a field of research was founded almost 100 years ago by Otto Warburg, who described the propensity for cancers to convert glucose to lactate despite the presence of oxygen, which in yeast diminishes glycolytic metabolism known as the Pasteur effect. In the past 20 years, the resurgence of interest in cancer metabolism provided significant insights into processes involved in maintenance metabolism of non-proliferating cells and proliferative metabolism, which is regulated by proto-oncogenes and tumor suppressors in normal proliferating cells. In cancer cells, depending on the driving oncogenic event, metabolism is re-wired for nutrient import, redox homeostasis, protein quality control, and biosynthesis to support cell growth and division. In general, resting cells rely on oxidative metabolism, while proliferating cells rewire metabolism toward glycolysis, which favors many biosynthetic pathways for proliferation. Oncogenes such as MYC, BRAF, KRAS, and PI3K have been documented to rewire metabolism in favor of proliferation. These cell intrinsic mechanisms, however, are insufficient to drive tumorigenesis because immune surveillance continuously seeks to destroy neo-antigenic tumor cells. In this regard, evasion of cancer cells from immunity involves checkpoints that blunt cytotoxic T cells, which are also attenuated by the metabolic tumor microenvironment, which is rich in immuno-modulating metabolites such as lactate, 2-hydroxyglutarate, kynurenine, and the proton (low pH). As such, a full understanding of tumor metabolism requires an appreciation of the convergence of cancer cell intrinsic metabolism and that of the tumor microenvironment including stromal and immune cells.

• 한국수정란이식학회지
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• 제30권3호
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• pp.249-255
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• 2015

Diabetes mellitus, the most common metabolic disorder, is divided into two types: type 1 and type 2. The essential treatment of type 1 diabetes, caused by immune-mediated destruction of ${\beta}-cells$, is transplantation of the pancreas; however, this treatment is limited by issues such as the lack of donors for islet transplantation and immune rejection. As an alternative approach, stem cell therapy has been used as a new tool. The present study revealed that bone marrowderived mesenchymal stromal cells (BM-MSCs) could be transdifferentiated into pancreatic cells by the insertion of a key gene for embryonic development of the pancreas, the pancreatic and duodenal homeobox factor 1 (PDX1). To avoid immune rejection associated with xenotransplantation and to develop a new cell-based treatment, BM-MSCs from ${\alpha}$-1,3-galactosyltransferase knockout (GalT KO) pigs were used as the source of the cells. Transfection of the EGFP-hPDX1 gene into GalT KO pig-derived BM-MSCs was performed by electroporation. Cells were evaluated for hPDX1 expression by immunofluorescence and RT-PCR. Transdifferentiation into pancreatic cells was confirmed by morphological transformation, immunofluorescence, and endogenous pPDX1 gene expression. At 3~4 weeks after transduction, cell morphology changed from spindle-like shape to round shape, similar to that observed in cuboidal epithelium expressing EGFP. Results of RT-PCR confirmed the expression of both exogenous hPDX1 and endogenous pPDX1. Therefore, GalT KO pig-derived BM-MSCs transdifferentiated into pancreatic cells by transfection of hPDX1. The present results are indicative of the therapeutic potential of PDX1-expressing GalT KO pig-derived BM-MSCs in ${\beta}-cell$ replacement. This potential needs to be explored further by using in vivo studies to confirm these findings.

• Clinical and Experimental Reproductive Medicine
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• 제30권1호
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• pp.15-21
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• 2003

Objective : Clomiphene citrate is one of the most commonly used drugs in the treatment of infertility, but the pregnancy rate achieved with clomiphene citrate is significantly lower than the ovulation rate due to its antiestrogenic effect on the endometrium. Endometrial prolactin is considered to be a marker and an inducer of predecidualization that is characteristic of secretory endometrium. The purpose of this study was to evaluate the association of clomiphene citrate and unsatisfactory endometrial differentiation to secretory endometrium by examining the endometrial expression of prolactin in clomiphene citratetreated infertile women with luteal phase defect. Methods : The endometrial samples from infertile women with luteal phase defect (n=27) were examined. Five cases during secretory phase and six cases during proliferative phase were obtained by biopsy. Sixteen cases were obtained by biopsy during secretory phase after clomiphene citrate treatment. By immunohistochemical staining for prolactin, all obtained endometrial tissues were examined. The differences in the endometrial expression of prolactin were evaluated between proliferative phase and secretory phase, and between clomiphene citrate treated group and no treatment group during secretory phase. Results: The staining of endometrial prolactin was significantly more intense in the glandular epithelial cells and stromal cells in the secretory endometrium than in the proliferative endometrium. The glandular expression of prolactin in the secretory endometrium was not significantly different between the clomiphene citrate-treated group and no treatment group (p=0.719), but the staining of prolactin in the stromal cells was significantly less intense in the clomiphene citrate-treated group than no treatment group (p=0.019). Conclusion: In this investigation, we demonstrated that the endometrial stromal expression of prolactin in the secretory phase was significantly lower in the clomiphene citrate-treated group campared with no treatment group in infertile women with luteal phase defect. And our finding suggests that clomiphene citrate may have an adverse effect on the endometrial predecidualization in infertile women.

• 한국수정란이식학회지
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• 제28권4호
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• pp.373-379
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• 2013

Spermatogonial stem cells (SSCs) developed into sperms through spermatogenesis have been utilized as a useful tool in the field of regenerative medicine and infertility. However, a small number of highly qualified SSCs are resided in the seminiferous tubule of testis, resulted in developing effective in-vitro culture system of SSCs for solving simultaneously quantitative and qualitative problems. Presently, SSCs can be enriched on testicular stromal cells (TSCs), but there are no systematic researches about TSC culture. Therefore, we tried to optimize culture condition of TSCs derived from mouse with different strains. For these, proliferation and viability were measured and compared by culturing ICR outbred or DBA/2 inbred mouse-derived TSCs at 35 or $37^{\circ}C$. In case of ICR strain, primary TSCs cultured at $37^{\circ}C$ showed significantly higher proliferation and viability than those at $35^{\circ}C$ and significant increase of proliferation and viability in sub-passaged TSCs was detected in the $35^{\circ}C$ culture condition. Moreover, sub-passage of primary TSCs at $35^{\circ}C$ induced no significant effects on proliferation and viability. In contrast, in case of DBA/2 strain, significantly improved proliferation were detected in the primary TSCs cultured at $35^{\circ}C$, which showed no significant difference in the viability, compared to those at $37^{\circ}C$. Furthermore, sub-passaged TSCs cultured at $37^{\circ}C$ showed no significant differences in proliferation and viability, compared to those at $35^{\circ}C$. However, with significant decrease of proliferation induced by sub-passage of primary TSCs at $35^{\circ}C$, no significant effects on proliferation and viability were resulted from sub-passage of primary TSCs at $37^{\circ}C$. From these results, culture temperature of primary TSCs derived from outbred and inbred strain of mouse could be separately optimized in primary culture and subculture.

• Molecules and Cells
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• 제40권2호
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• pp.133-142
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• 2017

Previous studies have shown that bone marrow mesenchymal stromal cell (MSC) transplantation significantly improves the recovery of neurological function in a rat model of intracerebral hemorrhage. Potential repair mechanisms involve anti-inflammation, anti-apoptosis and angiogenesis. However, few studies have focused on the effects of MSCs on inducible nitric oxide synthase (iNOS) expression and subsequent peroxynitrite formation after hypertensive intracerebral hemorrhage (HICH). In this study, MSCs were transplanted intracerebrally into rats 6 hours after HICH. The modified neurological severity score and the modified limb placing test were used to measure behavioral outcomes. Blood-brain barrier disruption and neuronal loss were measured by zonula occludens-1 (ZO-1) and neuronal nucleus (NeuN) expression, respectively. Concomitant edema formation was evaluated by H&E staining and brain water content. The effect of MSCs treatment on neuroinflammation was analyzed by immunohistochemical analysis or polymerase chain reaction of CD68, Iba1, iNOS expression and subsequent peroxynitrite formation, and by an enzyme-linked immunosorbent assay of pro-inflammatory factors (IL-$1{\beta}$ and TNF-${\alpha}$). The MSCs-treated HICH group showed better performance on behavioral scores and lower brain water content compared to controls. Moreover, the MSC injection increased NeuN and ZO-1 expression measured by immunochemistry/immunofluorescence. Furthermore, MSCs reduced not only levels of CD68, Iba1 and pro-inflammatory factors, but it also inhibited iNOS expression and peroxynitrite formation in perihematomal regions. The results suggest that intracerebral administration of MSCs accelerates neurological function recovery in HICH rats. This may result from the ability of MSCs to suppress inflammation, at least in part, by inhibiting iNOS expression and subsequent peroxynitrite formation.

• Clinical and Experimental Reproductive Medicine
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• 제25권1호
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• pp.25-33
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• 1998

Cyclooxygenase (COX) is an enzyme involved in the conversion of arachidonic acid to prostaglandins (PGs), and exists in two forms, COX-1 and COX-2. COX has been reported to be involved in early implantation by secretion of PGs which causes permeability of vessels and reaction of decidual cells around the implantation site. Recently, in mice and sheep studies, COX-1 and COX-2 expression in the endometrium has been reported to be different according to implantation and stages of the estrous cycle, but expression of COX-1 and COX-2 in human endometrium during the menstrual cycle has not yet been established. The purpose of this study was to observe the variances of COX-1 and COX-2 expression by immunohistochemical staining in endometrial samples obtained from human hysterectomy specimens and biopsies of women of reproductive age according to different stages of the menstrual cycle. Also, we attempted to observe COX-1 and COX-2 expression in the epithelial and stromal cells of the endometrium obtained during the mid-secretory phase, which were cultured separately. COX-2 showed a cyclic pattern of expression according to the different stages of the menstrual cycle and was strongly expressed particularly at the mid-secretory phase which corresponds to the time of implantation. However, COX-1 tended to be increased in the early proliferative, and mid- and late secretory phases, but was also expressed in the whole menstrual cycle showing no particular pattern. In the separately cultured cells COX-1 was expressed in epithilial cells and COX-2 in the stromal cells. The above results suggest that since COX-2 is expressed at the same time as implantation and cultured cells display a specific secretory pattern, COX-2 has inductive endocrine enzyme properties and has an important effect on endometrial cells during implantation. Also, COX-2 expression in endometrial cells may be utilized as a useful marker of endometrial maturation.

• Bulletin of the Korean Chemical Society
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• 제35권1호
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• pp.83-86
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• 2014

Poly(A) polymerase (PAP) play an essential role for maturation of mRNA by adding the adenylate residues at the 3' end. PAP functions are regulated through protein-protein interaction at its C-terminal region. In this study, cyclophilin A (CypA), a member of the peptidyl-prolyl cis-trans isomerase family, was identified as a partner protein interacting with the C-terminal region PAP. The interaction between PAP and CypA was inhibited by the immunosuppressive drug cyclosporine A. Deletion analysis revealed that the N-terminal 56 residues of CypA are sufficient for the interaction with PAP. Interestingly, we observed that PAP and CypA colocalize in the nucleus during SDF-1-induced chemotaxis, implying that CypA could be involved in the regulation of polyadenylation by PAP in the chemotactic cells.

• IMMUNE NETWORK
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• 제13권2호
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• pp.75-79
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• 2013

Evidence for immunoregulatory roles of prostaglandins (PGs) is accumulating. Since our observation of PG production by human follicular dendritic cells (FDCs), we investigated the regulatory mechanism of PG production in FDC and attempted to understand the functions of released PGs in the responses of adjacent lymphocytes. Here, using FDC-like cells, HK cells, we analyzed protein expression alterations in cyclooxygenase-2 (COX-2) in the presence of IL-4 or histone deacetylase (HDAC) inhibitors. Both IL-4 and HDAC inhibitors suppressed COX-2 expression in dose-dependent manners. Their effect was specific to COX-2 and did not reach to COX-1 expression. Interestingly, HDAC inhibitors gave rise to an opposing effect on COX-2 expression in peripheral blood monocytes. Our results suggest that IL-4 may regulate COX-2 expression in FDCs by affecting chromatin remodeling and provide insight into the role of cellular interactions between T cells and FDC during the GC reaction. Given the growing interests in wide-spectrum HDAC inhibitors, the differential results on COX-2 expression in HK cells and monocytes raise cautions on their clinical use.

• IMMUNE NETWORK
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• 제11권6호
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• pp.364-367
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• 2011

Background: Prostaglandins (PGs) play pathogenic and protective roles in inflammatory diseases. The novel concept of PGs as immune modulators is being documented by several investigators. By establishing an in vitro experimental model containing human follicular dendritic cell-like cells, HK cells, we reported that HK cells produce prostaglandin $E_2$ ($PGE_2$) and prostaglandin $I_2$ ($PGI_2$) and that these PGs regulate biological functions of T and B cells. Methods: To investigate the respective contribution of cyclooxygenase-1 (COX-1) and COX-2 to $PGE_2$ and $PGI_2$ production in HK cells, we performed siRNA technology to knock down COX enzymes and examined the effect on PG production. Results: Both $PGE_2$ and $PGI_2$ productions were almost completely inhibited by the depletion of COX-2. In contrast, COX-1 knockdown did not significantly affect PG production induced by lipopolysaccharide (LPS). Conclusion: The current results suggest that mPGES-1 and PGIS are coupled with COX-2 but not with COX-1 in human follicular dendritic cell (FDC) and may help understand the potential effects of selective COX inhibitors on the humoral immunity.

• Clinical and Experimental Reproductive Medicine
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• 제35권1호
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• pp.49-60
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• 2008

목 적: 자궁내막조직에서 분리한 상피세포와 기질세포를 삼차원 공배양을 통한 탈락막화 유도에서 성호르몬과 TGF-${\beta}1$의 역할을 알아보고 2-세포기 생쥐배아와 탈락막화가 유도된 자궁내막세포와의 공배양을 통하여 포배형성율, 부화율, 포배기배아의 내세포괴와 영양막세포수 및 부착율을 알아보기 위해 시행되었다. 연구방법: 인간 자궁내막조직에서 분리된 기질세포와 상피세포의 표지인자인 cytokeratin과 vimentin에 대한 면역조직 화학염색을 실시하여 분리를 확인하였으며, 성호르몬 우세환경 (progesterone, estrogen)에서 분리된 세포를 단일배양 혹은 3차원 공배양을 통하여 RT-PCR법으로 TGF-${\beta}1$, 수용체-1, -2, integrin-${\beta}3$, prolactin의 발현을 조사하였다. 배양액군을 대조군으로 하여 2-세포기 생쥐배아와 탈락막화 유도와 유도하지 않은 인간 자궁내막세포와의 공배양을 통하여 포배형성율, 부화율, 부착율과 부화된 포배의 영양막세포와 내세포괴수를 비교하였다. 결 과: 상피세포 표지인자인 cytokeratin과 기질세포 표지인자인 vimentin을 이용하여 면역조직화학염색을 한 결과 각각 95% 이상에서 양성반응을 나타내어 자궁내막조직으로부터 상피세포와 기질세포가 성공적으로 분리되었음을 확인하였다. 분리된 상피세포와 기질세포를 단일배양에서는 성호르몬의 조건에 관계없이 TGF-${\beta}1$과 수용체 type-1, type-2, integrin-${\beta}3$, prolactin mRNA가 발현되지 않았다. 공배양에서는 progesterone 우세환경일 경우 TGF-${\beta}1$ 수용체 type-2를 제외한 모든 mRNA가 발현하였으나 estrogen 우세환경에서는 TGF-${\beta}1$ 수용체 type-2와 prolactin이 발현되지 않았다. 2-세포기 생쥐배아를 배양액군, 비탈락막군 및 탈락막군으로 나누어 공배양하였을 때 포배기 발달율은 차이가 없었으나 부화율 (92%)과 부착율 (82%)은 탈락막군이 유의하게 높았으며 (p<0.05), 비탈락막군의 공배양에서 다수의 영양막세포가 투명대를 완전히 빠져나오지 않은 상태로 부착한 비정상형태를 보였다. 부화된 생쥐 포배기배아의 내세포괴수는 탈락막화에 관계없이 공배양한 포배의 내세포괴수가 유의하게 많았으며 (p<0.05), 영양막세포수는 탈락막군에서 배양액군과 비탈락막군보다 유의하게 많았다 (p<0.05). 결 론: 자궁내막조직에서 상피세포와 기질세포를 분리하여 다시 삼차원적 공배양을 통하여 progesterone (100 nM), estrogen (1 nM)과 TGF-${\beta}1$ (10 ng/ml)을 첨가하면 체외에서 탈락막화를 유도할 수 있으며, 탈락막화를 유도한 자궁내막 세포와 2-세포기 생쥐배아를 공배양하였을 때 탈락막화가 부화율, 부착율 및 영양막세포수에 유효한 영향을 미치는 것을 알 수 있었다.