핵의학적 세포증식 영상

여정석 대한핵의학회 2004 핵의학 분자영상 Vol.38 No.2

Tumor cell proliferation is considered to be a useful prognostic indicator of tumor aggressiveness and tumor response to therapy, but in vitro measurement of individual proliferation is complex and tedious work. PET imaging provides a noninvasive approach to measure tumor growth rate in situ. Early approaches have used ^(18)F-FDG or methionine to monitor proliferation status. These 2 tracers detect changes in glucose and amino acid metabolism, respectively, and therefore provide only an indirect measure of proliferation status. More recent studies have focused on DNA synthesis itself as a marker of cell proliferation. Cell lines and tissues with a high proliferation rate require high rates of DNA synthesis. [^(11)C]Thymidine was the first radiotracer for noninvasive imaging of tumor proliferation. The short half-life of ^(11)C and rapid metabolism of [^(11)C]thymidine in vivo make the radiotracer less suitable for routine use. Halogenated thymidine analogs such as 5-iodo-2-deoxyuridine (IUdR) can be successfully used as cell proliferation markers for in vitro studies because these compounds are rapidly incorporated into newly synthesized DNA. IUdR has been evaluated as a potential in vivo tracer in nuclear medicine, but the image quality and the calculation of proliferation rates are impaired by its rapid in vivo degradation. Hence, the thymidine analog 3'-deoxy-3'-^(18)F-fluorothymidine (FLT) was recently introduced as a stable proliferation marker with a suitable nuclide half-life and stable in vivo. [^(18)F]FLT is phosphorylated to 3-fluorothymidine monophosphate by thymidine kinase 1 and reflects thymidine kinase 1 activity in proliferating cell. [^(18)F]FLT PET is feasible in clincal use and well correlates with cellular proliferation. Choline is a precursor for the biosynthesis of phospholipids (in particular, phosphatidylcholine), which is the essential component of all eukaryotic cell membranes and [^(11)C]choline, which is a new marker for cellular proliferation. (Korean J Nucl Med 38(2):198-204, 2004)

Platelets Induce Proliferation of Human Umbilical Vein Endothelial Cells via CD154-CD40 Pathway Independently of VEGF

조화정,고은미,천인수,정두일,김영명,최종선 대한면역학회 2008 Immune Network Vol.8 No.3

Background: Platelets take part in repairing the lesions of endothelial damage. To understand the molecular mechanism of this process, we tested the hypothesis that CD154 expressed on activated platelets stimulates proliferation of human endothelial cells. Methods: The expression levels of CD154 and CD40 on platelets and endothelial cells, respectively, were measured by flow cytometry and confocalmicroscopy. Function-blocking monoclonal antibody against CD154 was developed after immunization with CD154- transfected L cells. Results: An anti-CD40 agonist antibody and soluble CD154 both induced significant proliferation ofendothelial cells. In addition, a function-blocking anti-CD154 a ntibody inhibited the platelet-induced proliferation of endothelial cells, indicating that the CD154-CD40 pathway is involved in these cellular interactions. An anti-VEGF antibody failed to inhibit the proliferation. This, in addition to the fact that very small amounts of VEGF are released from platelets or endothelial cells, suggests that VEGF does not play an important role in the platelet-stimulated proliferation of endothelial cells. Conclusion: Our results indicate that platelets induce proliferation of endothelial cells by CD154-CD40 interactions independently of VEGF. Background: Platelets take part in repairing the lesions of endothelial damage. To understand the molecular mechanism of this process, we tested the hypothesis that CD154 expressed on activated platelets stimulates proliferation of human endothelial cells. Methods: The expression levels of CD154 and CD40 on platelets and endothelial cells, respectively, were measured by flow cytometry and confocalmicroscopy. Function-blocking monoclonal antibody against CD154 was developed after immunization with CD154- transfected L cells. Results: An anti-CD40 agonist antibody and soluble CD154 both induced significant proliferation ofendothelial cells. In addition, a function-blocking anti-CD154 a ntibody inhibited the platelet-induced proliferation of endothelial cells, indicating that the CD154-CD40 pathway is involved in these cellular interactions. An anti-VEGF antibody failed to inhibit the proliferation. This, in addition to the fact that very small amounts of VEGF are released from platelets or endothelial cells, suggests that VEGF does not play an important role in the platelet-stimulated proliferation of endothelial cells. Conclusion: Our results indicate that platelets induce proliferation of endothelial cells by CD154-CD40 interactions independently of VEGF.

국제사회의 핵통제사례를 통해 본 북핵문제 해결방안: ‘통제된 핵확산’의 필요성

노병렬 세종연구소 2006 국가전략 Vol.12 No.3

Since the advent of nuclear weapons, there have been two ways to deal with the horror of nuclear war: one is nuclear deterrence and the other is nonproliferation efforts. Even though a nuclear weapon gets various assessments of its actual effectiveness, it has won strategic value, which leads to overall reorganization of the existing military strategy, all by itself. Each nation has tried to develop nuclear weapons to dissolve the uneasiness of its security, to instil nationalism or to stay in power, and the tendency has continued to the present. Additionally, the world having experienced the deadly destructive power of the nuclear weapon tries to prevent nuclear proliferation with international laws and institutions. However, the efforts to prevent nuclear proliferation by all the countries involved and international organizations led by the United States have come to face a challenge from the nuclear proliferating countries. Especially, current nuclear proliferation by North Korea shows a new vision on the nuclear proliferation of the world. Purposes of this paper are classified into three objectives. First of all, this paper points out that nuclear proliferation can not be stopped by all means if new proliferators seek nuclear development because of vital national interests. Second, North Korea's nuclear facilities and capabilities are already defined to one of nuclear powers. Finally, South Korea and the United States must develop and suggest new approach such as 'controlled proliferation' to deal with North Korean nuclear issues. 국제 핵확산에 대한 상반된 대응이 나타나고 있는 가운데 북한 핵문제를 풀기 위한 6자회담은 여전히 답보상태에 놓여 있다. 한국의 대북 정책 역시 북한 핵에 대하여 원칙적인 입장만 견지하고 있을 뿐 구체적인 대안제시가 나오지 않고 있다. 미국과 북한은 해결방식의 우선순위를 두고 대치되어 있으며, 중국이나 일본, 그리고 러시아의 중재방안도 각 국가들이 가지고 있는 개별 동맹관계의 특수성이나 동북아시아에서의 전략적 이익에 기초하여 이루어지고 있기 때문에 별다른 영향력을 발휘하지 못하고 있다. 본 연구의 출발점은 핵무기의 효용성에 대한 국제사회의 양면적 성격을 감안하면, 핵확산은 상당기간 진행될 것이며 새로운 핵확산의 원인해결이 선행되지 않은 상황에서의 핵통제는 실효성이 없다는 것이다. 따라서 핵확산에 대한 대응핵확산전략은 새로운 관점에서 추구되어야하며, 본 연구는 대응핵확산의 일환으로서의 ‘통제된 핵확산’의 필요성을 제시하고자 한다. 핵확산이 피할 수 없는 현상이고 이미 발생한 것이라면 국제사회는 핵확산을 효과적으로 통제하여 안정적으로 운용하는 것이 보다 국가간 이익을 보호하여 줄 수 있는 것으로 인식을 전환시켜야 한다. ‘통제된 핵확산’은 이미 발생한 핵확산을 안정적으로 관리하기 위한 정책의 한 부분이다. 통제된 핵확산은 규범적이거나 원칙적인 입장에서 국제사회의 핵문제를 다루는 것이 아니라 지극히 현실적인 인식에서 문제해결을 하려는 시도로 볼 수 있다.

miR-458b-5p regulates ovarian granulosa cells proliferation through Wnt/β‐catenin signaling pathway by targeting catenin beta-1

Wang Wenwen,Teng Jun,Han Xu,Zhang Shen,Zhang Qin,Tang Hui 아세아·태평양축산학회 2021 Animal Bioscience Vol.34 No.6

Objective: Ovarian follicular development, which dependent on the proliferation and differentiation of granulosa cells (GCs), is a complex biological process in which miRNA plays an important role. Our previous study showed that miR-458b-5p is associated with ovarian follicular development in chicken. The detailed function and molecular mechanism of miR-458b-5p in GCs is unclear. Methods: The luciferase reporter assay was used to verify the targeting relationship between miR-458b-5p and catenin beta-1 (CTNNB1), which is an important transcriptional regulatory factor of the Wnt/β-catenin pathway. The cell counting kit-8 (CCK-8) assay, flow cytometry with propidium iodide (PI) and annexin V-fluorescein isothiocyanate (FITC) labeling were applied to explore the effect of miR-458b-5p on proliferation, cell cycle and apoptosis of chicken GCs. Quantitative real-time polymerase chain reaction and Western blot were used to detect the mRNA and protein expression levels. Results: We demonstrated that the expression of miR-458b-5p and CTNNB1 showed the opposite relationship in GCs and theca cells of hierarchical follicles. The luciferase reporter assay confirmed that CTNNB1 is the direct target of miR-458b-5p. Using CCK-8 assay and flow cytometry with PI and Annexin V-FITC labeling, we observed that transfection with the miR-458b-5p mimics significantly reduced proliferation and has no effects on apoptosis of chicken GCs. In addition, miR-458b-5p decreased the mRNA and protein expression of CD44 molecule and matrix metallopeptidase 7, which are the downstream effectors of CTNNB1 in Wnt/β-Catenin pathway and play functional roles in cell proliferation. Conclusion: Taken together, the data indicate that miR-458b-5p regulates ovarian GCs proliferation through Wnt/β-catenin signaling pathway by targeting CTNNB1, suggesting that miR-458b-5p and its target gene CTNNB1 may potentially play a role in chicken ovarian follicular development. Objective: Ovarian follicular development, which dependent on the proliferation and differentiation of granulosa cells (GCs), is a complex biological process in which miRNA plays an important role. Our previous study showed that miR-458b-5p is associated with ovarian follicular development in chicken. The detailed function and molecular mechanism of miR-458b-5p in GCs is unclear.Methods: The luciferase reporter assay was used to verify the targeting relationship between miR-458b-5p and catenin beta-1 (<i><i>CTNNB1</i></i>), which is an important transcriptional regulatory factor of the Wnt/β-catenin pathway. The cell counting kit-8 (CCK-8) assay, flow cytometry with propidium iodide (PI) and annexin V-fluorescein isothiocyanate (FITC) labeling were applied to explore the effect of miR-458b-5p on proliferation, cell cycle and apoptosis of chicken GCs. Quantitative real-time polymerase chain reaction and Western blot were used to detect the mRNA and protein expression levels.Results: We demonstrated that the expression of miR-458b-5p and <i>CTNNB1</i> showed the opposite relationship in GCs and theca cells of hierarchical follicles. The luciferase reporter assay confirmed that <i>CTNNB1</i> is the direct target of miR-458b-5p. Using CCK-8 assay and flow cytometry with PI and Annexin V-FITC labeling, we observed that transfection with the miR-458b-5p mimics significantly reduced proliferation and has no effects on apoptosis of chicken GCs. In addition, miR-458b-5p decreased the mRNA and protein expression of CD44 molecule and matrix metallopeptidase 7, which are the downstream effectors of <i>CTNNB1</i> in Wnt/β-Catenin pathway and play functional roles in cell proliferation.Conclusion: Taken together, the data indicate that miR-458b-5p regulates ovarian GCs proliferation through Wnt/β-catenin signaling pathway by targeting <i>CTNNB1</i>, suggesting that miR-458b-5p and its target gene <i>CTNNB1</i> may potentially play a role in chicken ovarian follicular development.

P282 : Silver nanoparticles-induced human mesenchymal stem cell proliferation is associated with HIF-1α-mediated upregulation of IL-8 expression

( Sung Kyu Jung ),( Jin Hee Kim ),( Sang Wook Son ) 대한피부과학회 2013 대한피부과학회 학술발표대회집 Vol.65 No.2

Background: Hypoxia-inducible factor-1α (HIF-1α) is a transcriptional factor that regulates several aspects of stem cell biology, including proliferation, differentiation, and survival. Silver nanoparticles (AgNPs) show efficacy in wound healing by increasing cell proliferation. Objectives: However, there is a lack of information on the biological pathway with HIF-1αthat can explain the effects of AgNPs on the proliferation of human mesenchymal stem cells (hMSCs). Methods: To evaluate the role of HIF-1α in AgNPs-treated hMSCs, we investigated the cell proliferation and the expression of IL-8 in hMSCs treated with AgNPs. In addition, we observed the level of cell proliferation and the expression of IL-8 in hSMCs treated with siRNA specific to HIF-1α. Results: AgNPs increased the expression of HIF-1α in hMSCs. IL-8 expression and cell proliferation were significantly increased in the hMSCs treated with AgNPs (1 μg, 2.5 μg, 5 μg, and 7.5 μg) compared with the untreated hMSCs. Moreover, the cell proliferation and expression of IL-8 in the AgNPs-treated hMSCs was significantly reduced after HIF-1α siRNA treatment. Conclusion: Our findings suggest that AgNPs-induced hMSCs proliferation may be associated with the upregulation of IL-8 expression mediated by HIF-1α.

Effects of Tamoxifen at Different Concentrations and Treatment Periods on Proliferation of HeLa

Hyunhee Kim,Gyesik Min 한국동물번식학회 2012 Reproductive & Developmental Biology(Supplement) Vol.36 No.2s

This study examined the effects of tamoxifen at different concentrations and treatment periods on proliferation of a human cervical cancer cell line, HeLa. As in the previous studies, Estrogen did not have an effect on the cellular proliferation at low concentrations but significantly reduced proliferation at high concentration (5 ug/ml) based on MTT assay. Treatment with tamoxifen had similar effects. It did not have any significant effect on the HeLa cell proliferation at low concentrations, but significantly reduced proliferation at high concentration (10 uM). In addition, combined treatment with both estrogen and tamoxifen did not alter the inhibitory effects of either estrogen or tamoxifen on cellular proliferation. The inhibitory effects by tamoxifen on HeLa cell proliferation did not differ among different treatment periods. This suggests that tamoxifen may exert anti- proliferative effects at high concentration but does not have synergistic or antagonistic effects against estrogen on HeLa cell proliferation.

Inhibitory Effects of High Concentrations of Estrogen, Progesterone and Tamoxifen on Proliferation of HeLa in Culture

Gyesik Min(민계식) 한국생명과학회 2011 생명과학회지 Vol.21 No.12

이 연구는 에스트로겐, 프로게스테론 및 타목시펜의 각각 다른 농도와 처리기간에 따라 배양된 사람 난소유래 암세포주인 HeLa 세포의 증식에 미치는 영향을 MTT 분석에 의해 조사하였다. 에스트로겐은 2.5~6일의 처리기간동안 1 ㎍/ml의 농도까지는 세포증식에 영향을 주지 않았지만, 더 높은 10 ㎍/ml의 농도에서는 처리기간의 증가에 따라 점진적으로 현저하게 세포증식을 억제하였다. 또한 10 ㎍/ml 농도 이상의 프로게스테론을 2.5일 동안 처리할 경우 HeLa 세포의 증식을 현저하게 억제하였으며, 4일 동안 처리시에는 농도-의존성 억제효과를 나타내었다. 그러나, 6일 동안 더 장기간의 프로게스테론 처리는 4일 동안의 처리기간에서 관찰된 세포증식에 대한 농도-의존성 억제효과를 제거하였다. 그리고, 타목시펜은 HeLa 세포주의 증식에 대한 억제효과를 위하여 에스트로겐보다 더 높은 농도(100 ㎍/ml)를 필요로 하였다. 이러한 결과는 고농도의 에스트로겐, 프로게스테론 그리고 타목시펜이 HeLa 세포의 증식을 억제할 뿐만 아니라, 농도 및 처리기간 또한 세포증식에 대한 억제효과에 영향을 미칠 수 있음을 제시한다. This study examined the effects of estrogen, progesterone and tamoxifen at different concentrations and treatment periods on proliferation of a human cervical carcinoma cell line, HeLa, in culture, based on MTT assay. Estrogen did not have an effect on the cellular proliferation in concentrations up to 1 ㎍/ml for treatment periods of between 2.5 and 6 days, but significantly inhibited proliferation at a higher concentration of 10 ㎍/ml in a progressive manner with increasing treatment periods. Also, treatment of HeLa with more than 10 ㎍/ml of progesterone for 2.5 days significantly inhibited proliferation and caused a concentration-dependent inhibition with 4 days of treatment. However, longer treatment with progesterone for 6 days abolished the concentration-dependent inhibitory effect on cellular proliferation observed with the 4-day treatment period. Furthermore, tamoxifen required a higher concentration (100 ㎍/ml) than estrogen to bring about the inhibitory effect on the HeLa proliferation. These results suggest that high concentrations of estrogen, progesterone and tamoxifen may suppress proliferation of HeLa, and both the concentration and the treatment period may also influence their inhibitory effects on cellular proliferation.

Inhibitory effects of ginsenosides on basic fibroblast growth factorinduced melanocyte proliferation

이지은,박종일,명철환,황재성 고려인삼학회 2017 Journal of Ginseng Research Vol.41 No.3

Background: UV-B-exposed keratinocytes secrete various paracrine factors. Among these factors, basic fibroblast growth factor (bFGF) stimulates the proliferation of melanocytes. Ginsenosides, the major active compounds of ginseng, are known to have broad pharmacological effects. In this study, we examined the antiproliferative effects of ginsenosides on bFGF-induced melanocyte proliferation. Methods: We investigated the inhibitory effects of Korean Red Ginseng and ginsenosides from Panax ginseng on bFGF-induced proliferation of melan-a melanocytes. Results: When melan-a melanocytes were treated with UV-B-irradiated SP-1 keratinocytes media, cell proliferation increased. This increased proliferation of melanocytes decreased with a neutralizing antibFGF antibody. To elucidate the effects of ginsenosides on melanocyte proliferation induced by bFGF, we tested 15 types of ginsenoside compounds. Among them, Rh3, Rh1, F1, and CK demonstrated antiproliferative effects on bFGF-induced melanocyte proliferation after 72 h of treatment. bFGF stimulated cell proliferation via extracellular signal-regulated kinase (ERK) activation in various cell types. Western blot analysis found bFGF-induced ERK phosphorylation in melan-a. Treatment with Rh3 inhibited bFGFinduced maximum ERK phosphorylation and F1-delayed maximum ERK phosphorylation, whereas Rh1 and CK had no detectable effects. In addition, cotreatment with Rh3 and F1 significantly suppressed bFGF-induced ERK phosphorylation. Western blot analysis found that bFGF increased microphthalmiaassociated transcription factor (MITF) protein levels in melan-a. Treatment with Rh3 or F1 had no detectable effects, whereas cotreatment with Rh3 and F1 inhibited bFGF-induced MITF expression levels more strongly than a single treatment. Conclusion: In summary, we found that ginsenosides Rh3 and F1 have a synergistic antiproliferative effect on bFGF-induced melan-a melanocyte proliferation via the inhibition of ERK-mediated upregulation of MITF.

Far-Infrared Irradiation Decreases Proliferation in Basal and PDGF-Stimulated VSMCs Through AMPK-Mediated Inhibition of mTOR/p70S6K Signaling Axis

Hwang Yun-Jin,Park Jung-Hyun,Cho Du-Hyong 대한의학회 2023 Journal of Korean medical science Vol.38 No.41

Background: Far-infrared (FIR) irradiation has been reported to improve diverse cardiovascular diseases, including heart failure, hypertension, and atherosclerosis. The dysregulated proliferation of vascular smooth muscle cells (VSMCs) is well established to contribute to developing occlusive vascular diseases such as atherosclerosis and in-stent restenosis. However, the effects of FIR irradiation on VSMC proliferation and the underlying mechanism are unclear. This study investigated the molecular mechanism through which FIR irradiation inhibited VSMC proliferation. Methods: We performed cell proliferation and cell death assay, adenosine 5′-triphosphate (ATP) assay, inhibitor studies, transfection of dominant negative (dn)-AMP-activated protein kinase (AMPK) α1 gene, and western blot analyses. We also conducted confocal microscopic image analyses and ex vivo studies using isolated rat aortas. Results: FIR irradiation for 30 minutes decreased VSMC proliferation without altering the cell death. Furthermore, FIR irradiation accompanied decreases in phosphorylation of the mammalian target of rapamycin (mTOR) at Ser2448 (p-mTOR-Ser2448) and p70 S6 kinase (p70S6K) at Thr389 (p-p70S6K-Thr389). The phosphorylation of AMPK at Thr172 (p-AMPKThr172) was increased in FIR-irradiated VSMCs, which was accompanied by a decreased cellular ATP level. Similar to in vitro results, FIR irradiation increased p-AMPK-Thr172 and decreased p-mTOR-Ser2448 and p-p70S6K-Thr389 in isolated rat aortas. Pre-treatment with compound C, a specific AMPK inhibitor, or ectopic expression of dn-AMPKα1 gene, significantly reversed FIR irradiation-decreased VSMC proliferation, p-mTOR-Ser2448, and p-p70S6K-Thr389. On the other hand, hyperthermal stimulus (39°C) did not alter VSMC proliferation, cellular ATP level, and AMPK/mTOR/p70S6K phosphorylation. Finally, FIR irradiation attenuated plateletderived growth factor (PDGF)-stimulated VSMC proliferation by increasing p-AMPK-Thr172, and decreasing p-mTOR-Ser2448 and p-p70S6K-Thr389 in PDGF-induced in vitro atherosclerosis model. Conclusion: These results show that FIR irradiation decreases the basal and PDGF-stimulated VSMC proliferation, at least in part, by the AMPK-mediated inhibition of mTOR/p70S6K signaling axis irrespective of its hyperthermal effect. These observations suggest that FIR therapy can be used to treat arterial narrowing diseases, including atherosclerosis and in-stent restenosis.

Inhibitory effects of ginsenosides on basic fibroblast growth factor-induced melanocyte proliferation

Ji Eun Lee,Jong Il Park,Cheol Hwan Myung,Jae Sung Hwang 고려인삼학회 2017 Journal of Ginseng Research Vol.41 No.3

Background: UV-B-exposed keratinocytes secrete various paracrine factors. Among these factors, basic fibroblast growth factor (bFGF) stimulates the proliferation of melanocytes. Ginsenosides, the major active compounds of ginseng, are known to have broad pharmacological effects. In this study, we examined the antiproliferative effects of ginsenosides on bFGF-induced melanocyte proliferation. Methods: We investigated the inhibitory effects of Korean Red Ginseng and ginsenosides from Panax ginseng on bFGF-induced proliferation of melan-a melanocytes. Results: When melan-a melanocytes were treated with UV-B-irradiated SP-1 keratinocytes media, cell proliferation increased. This increased proliferation of melanocytes decreased with a neutralizing antibFGF antibody. To elucidate the effects of ginsenosides on melanocyte proliferation induced by bFGF, we tested 15 types of ginsenoside compounds. Among them, Rh3, Rh1, F1, and CK demonstrated antiproliferative effects on bFGF-induced melanocyte proliferation after 72 h of treatment. bFGF stimulated cell proliferation via extracellular signal-regulated kinase (ERK) activation in various cell types. Western blot analysis found bFGF-induced ERK phosphorylation in melan-a. Treatment with Rh3 inhibited bFGFinduced maximum ERK phosphorylation and F1-delayed maximum ERK phosphorylation, whereas Rh1 and CK had no detectable effects. In addition, cotreatment with Rh3 and F1 significantly suppressed bFGF-induced ERK phosphorylation. Western blot analysis found that bFGF increased microphthalmiaassociated transcription factor (MITF) protein levels in melan-a. Treatment with Rh3 or F1 had no detectable effects, whereas cotreatment with Rh3 and F1 inhibited bFGF-induced MITF expression levels more strongly than a single treatment. Conclusion: In summary, we found that ginsenosides Rh3 and F1 have a synergistic antiproliferative effect on bFGF-induced melan-a melanocyte proliferation via the inhibition of ERK-mediated upregulation of MITF.