• Bulletin of the Korean Chemical Society
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• 제28권4호
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• pp.652-656
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• 2007

Hydroxyapatite [Ca10(PO4)6(OH)2, HAp] and titanium(Ti) metal are known to be excellent materials with high affinities for natural bone through the apatite. Tricalcium phosphate [Ca3(PO4)2, TCP] is a promising alternative material because it is similar to HAp in its physical properties and biocompatibility. To examine the influence of hydroxyapatite, tricalcium phosphate, pure titanium and pre-treated titanium on osteopontin expression in osteoblasts, RNA was extracted from proliferated and cultured osteoblast cells and OPN mRNA expression was observed by RT-PCR.

• Asian Pacific Journal of Cancer Prevention
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• 제14권12호
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• pp.7315-7319
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• 2013

Background: The metastasis gene osteopontin (OPN) is subject to alternative splicing, which yields three messages, osteopontin-a, osteopontin-b and osteopontin-c. Osteopontin-c is selectively expressed in invasive, but not in noninvasive tumors. In the present study, we examined the expression of OPN-c in esophageal squamous cell carcinomas (ESCCs) and assessed its value as a diagnostic biomarker. Methods: OPN-c expression was assessed by immunohistochemistry in 63 ESCC samples and correlated with clinicopathologic factors. Expression was also examined in peripheral blood mononuclear cells (PBMCs) from 120 ESCC patients and 30 healthy subjects. The role of OPN-c mRNA as a tumor marker was investigated by receiver operating characteristic curve (ROC) analysis. Results: Immunohistochemistry showed that OPN-c was expressed in 30 of 63 cancer lesions (48%)and significantly associated with pathological T stage (P=0.038) and overall stage (P=0.023). Real time PCR showed that OPN-c mRNA was expressed at higher levels in the PBMCs of ESCC patients than in those of healthy subjects (P<0.0001) with a sensitivity as an ESCC biomarker of 86.7%. Conclusion: Our findings suggest that expression of OPN-c is significantly elevated in ESCCs and this upregulation could be a potential diagnostic marker.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.142.2-142.2
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• 2003

The activation of the hepatic stellate cell (HSC) is a key step in liver fibrogenesis. We investigated the changes of global gene expression during activation in hepatic stellate cells using a rat cDNA microarray with 5, 000 sequence-verified clones. We identified osteopontin (OPN), a secreted matrix protein, as one of the upregulated factors. Northern analysis showed OPN mRNA was increasingly expressed during progressive activation of cultured rat HSCs and in models of experimental liver fibrosis. (omitted)

• Journal of Nutrition and Health
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• 제49권1호
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• pp.59-62
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• 2016

Purpose: Zinc, a biomineral present within and outside cells, manages various cellular mechanisms. In this study, we examined whether zinc was involved in vascular smooth muscle cell (VSMC) calcification via regulation of calcification inhibitor protein, osteopontin (OPN). Methods: Rat aorta cell line (A7r5 cells) and primary vascular smooth muscle cells (pVSMCs) from rat aorta were cultured with phosphate (1-5 mM) and zinc ($0-15{\mu}M$) as appropriate, along with osteoblasts (MC3T3-E1) as control. The cells were then stained for Ca and P deposition for calcification examination as well as osteopontin expression as calcification inhibitor protein was measured. Results: Both Ca and phosphate deposition increased as the addition of phosphate increased. In the same manner, the expression of osteopontin was upregulated as the addition of phosphate increased in both cell types. When zinc was added, Ca and P deposition decreased in VSMCs, while it increased in osteoblasts. Conclusion: The results imply that zinc may prevent VSMC calcification by stimulating calcification inhibitor protein OPN synthesis in VSMCs.

• Imaging Science in Dentistry
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• 제38권4호
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• pp.195-202
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• 2008

Purpose : To characterize the effects of 2-deoxy-D-glucose (2-DG) and quercetin (QCT) on gene expression of osteonectin (ON) and osteopontin (OP) in irradiated MC3T3-El cells. Materials and Methods : When MC3T3-El osteoblastic cells had reached 70-80% confluence, cultures were transferred to a differentiating medium supplemented with 5 mM 2-DG or 10 ${\mu}M$ QCT and then irradiated with 2, 4, 6, and 8 Gy. At various times after irradiation, the cells were analyzed for the expression of bone mineralization genes such as ON and OP. Results : The mRNA expression of both ON and OP was increased according to the culture time in the differentiation medium, and the increase of the genes peaked at 14 days after the differentiation induction. In the case of OP, the increase of mRNA expression was maintained to 28 days after the differentiation, while the mRNA level of ON was reduced to the basal level at the same time. Irradiation adding 2-DG showed a significant peak value in the expression pattern of ON at 4 Gy 7 days after irradiation. Irradiation adding QCT increased the mRNA expression of ON and OP in a dose-dependant manner, but irradiation adding 2-DG did not show any differences between the control and experiments 14 days after irradiation. Irradiation adding QCT increased significantly the expression patterns of ON 21 days after irradiation. Conclusion : The results showed that QCT acted as a radiosensitizer in the gene expression of ON and OP during differentiation of the late stage of irradiated MC3T3-E1 osteoblastic cells in vitro. (Korean J Oral Maxillofac Radiol 2008; 38: 195-202)

• Asian Pacific Journal of Cancer Prevention
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• 제15권1호
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• pp.29-32
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• 2014

Background and Objective: Lung cancer is one of the malignant diseases which most seriously threat humansurvival and development. This study aimed to assess osteopontin (OPN) expression in non-small cell lung cancer (NSCLC) and any relationship with clinicopathological features. Methods: Immunohistochemistry was used to determine OPN expression and microvascular density (MVD) in 120 cases of NSCLC also undergoing clinical assessment. Results: Moderately positive expression of OPN was found in 34.6% (41/120) and strong expression in 47.5% (57/120) of the NSCLCs; OPN expression in carcinomas was higher than in pericarcinoma tissues (P<0.05). While no obvious association was observed with NSCLC patient age, gender, maximum diameter of the tumor and pathological type, OPN expression was more commonly detected in poorly differentiated carcinoma tissue and lymph node metastasis as well as at advanced clinical stage (P<0.05); OPN expression in cancer tissue was positively correlated with MVD (r = 0.839, P = 0.000). Conclusion: OPN plays an important role in promoting tumor angiogenesis and progress of NSCLCs and has the possibility to become the new target for therapy.

• Asian Pacific Journal of Cancer Prevention
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• 제17권1호
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• pp.201-205
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• 2016

Cholangiocarcinoma (CCA) is generally a rare primary liver tumor of the bile duct with extremely poor clinical outcomes due to late diagnosis. Osteopontin (OPN) is the most abundant expressed gene in intrahepatic CCA and its involvement in tumor aggressiveness suggests it could be a useful prognostic biomarker. However, the prognostic significance of OPN expression in CCA is still controversial. We therefore immunohistochemically studied OPN expression in 354 resected CCAs and correlated the results with patient clinicopathological parameters. OPN expression was separately scored according to the percentage of cancer cells or degree of stromal tissue staining and classified as low (score 0-1) and high (score 2-3). OPN expression in CCA cells was found in 177 out of 354 patients (56.5%), whereas stroma was positive in 185 out of 354 patients (52.3%). Univariate analysis with several of the aforementioned parameters revealed that stromal but not cancer cell OPN expression was significantly associated with tumor size, tumor direct invasion into normal liver parenchyma, regional lymph node metastasis and higher staging. The combination of cancer cell and stromal OPN expression demonstrated a positive trend for linkage with lymph node metastasis. Multivariate analysis identified gender, the presence of lymphatic permeation and lymph node metastasis, but not OPN expression, as independent prognostic factors. This study confirms the presence of stromal OPN expression in tumor aggressiveness but not survival in CCA patients.

• 대한소아치과학회지
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• 제27권2호
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• pp.309-317
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• 2000

본 실험은 bisphosphonate가 조골세포 분화 및 파골세포 분화에 미치는 영향을 알아보고자, etidronate와 alendronate를 조골세포에 투여하여 조골세포 전사인자인 Cbfa1, 조골세포 표시 인자의 발현, 석회화된 골결절 형성을 평가하였다. Bisphosphonate가 조골세포의 석회화된 골결절 형성에 미치는 영향을 평가하기 위하여 배양액에 $10^{-6},\;10^{-5},\;10^{-4}M$의 etidronate 및 $10^{-8},\;10^{-7},\;10^{-6}M$의 alendronate를 첨가하였으며, 배양 15일 후에 alizarin red로 염색하여 관찰하였다. 또 조골세포의 분화에 미치는 bisphosphonate의 영향을 평가하고자 백서 두개관에서 얻은 조골세포에 etidronate $10^{-6},\;10^{-5},\;10^{-4}M$ 및 alendronate $10^{-6}$ M을 투여하고 배양 8일 후 총RNA를 수집하였고, 전기영동 및 Northern blot hybridization하여 Cbfa1, alkaline phosphatase, type I collagen, osteopontin, osteocalcin의 발현을 조사하였다. 이상의 실험결과 다음과 같은 결론을 얻었다. 1. Etidronate는 농도 의존적으로 골결절 석회화를 억제하였으나, alendronate는 골석회화를 억제하지 않았다. 2. Etidronate는 Cbfa1의 발현을 농도 의존적으로 억제하였으나, alendronate는 오히려 촉진하였다. 3. Etidronate는 type I collagen, osteocalcin 및 osteopontin의 발현을 농도 의존적으로 억제하였으나, alendronate는 오히려 증가시켰다. 4. Alkaline phosphatase의 발현은 사용된 etidronate와 alendronate에 의해 영향 받지 않았다. 이상의 결과에서 etidironate는 조골세포의 전사인자인 Cbfa1의 발현을 억제하며, 이에 의하여 조골세포의 분화표지인자인 type I collagen, osteopontin 및 osteocalcin의 합성이 억제되고, 결과적으로 석회화된 골결절의 형성을 억제하는 것으로 사료된다.

• 대한소아치과학회지
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• 제27권2호
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• pp.300-308
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• 2000

Fibroblast growth factor(FGF)는 세포의 성장과 이동, 분화와 생존과 관련된 여러가지 과정을 조절하는 것으로 알려져 있다. 이들의 prototype인 FGF-1과 FGF-2는 FGF receptors (FGFRs)를 통해서 세포내로 신호를 전달하는데, 두개봉합부의 조기융합을 보이는 craniosynostosis는 FGFRs중, 특히 FGFR-2의 point mutation에 의해서 야기된다. 최근 여러 보고에서 FGF/FGFR 신호전달은 골아세포의 분화에 있어 필수적인 역할을 한다고 하였으며, bFGF soaked bead를 쥐 두개골의 시상봉합부의 mid-mesenchyme과 osteogenic front부위에 적용하였을 때 osteopontin(OPN) 유전자의 발현을 유도한다고 하였다. 이에 본 연구에서는 ST-2 cell line를 이용한 in vitro실험에서 bFGF가 OPN 유전자 발현에 미치는 영향과 그 기전을 Northern blot analysis를 통해서 연구하고자 하였다. 1 ng/ml bFGF의 투여는 OPN, fibronectin 유전자 발현을 증가시켰으며, type I collagen 유전자 발현은 감소시켰으나 alkaline phosphatase 유전자 발현에는 영향을 미치지 않았다. OPN은 그 발현양상이 bFGF의 농도 증가에 따라 증가하는 양상으로 나타났으며, 시간결과에 따른 발현양상도 bFGF 투여 3시간째부터 bFGF를 투여한 군에서 대조군에 비해 높게 나타났으며 이는 24시간까지 시간의 경과에 따라 증가하는 양상을 보였다. 단백질 합성 억제제인 cycloheximide를 처리한 군에서는 OPN의 증가 양상을 보이지 않았는데 이는 bFGF에 의한 OPN유전자 발현이 새로운 전사조절 단백질 합성 등의 여러 단계를 거쳐서 일어남을 의미한다. 결론적으로 bFGF는 새로운 전사조절 단백질의 합성을 통해서 OPN 유전자 발현을 농도 및 시간 의존적으로 증가시킨다.

• 대한소아치과학회지
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• 제26권4호
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• pp.652-663
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• 1999

두개봉합부의 조기융합으로 알려진 Craniosynostosis는 두개봉합부 주위 조직들 사이의 조화로운 상호작용이 파괴되었을 때 야기될 수 있다. 흥미롭게도 FGF receptor들, 특히 FGFR2의 point mutation은 여러 가지 형태의 craniosynostosis 증후군과 연관되어 있어, FGFR가 두개봉합부를 포함한 두개골 성장발달과정에 중요한 유전자임을 시사하고 있다. Mouse 두개봉합부의 초기형태발생시 FGFR 유전자들의 기능을 알아보기위해, in situ hybridization 방법을 이용하여 FGFR2(BEK) 및 골아세포분화의 초기표지자인 osteopontin이, 태생기(E15-18)에서 출생후(P1-P3)까지, 두개골의 시상봉합부에서의 발현양상을 조사하였다. FGFR2(BEK)은 osteogenic fronts에 강하게 발현되었으며, osteopontin은 parietal bone의 exo-, endocranial부위에서 발현되었으나, parietal bone의 성장가장자리인 osteogenic front에서는 관찰되지 않았다. 두개봉합부에서의 FGF-mediated FGFR signaling의 역할을 좀더 심도깊게 조사하기위해 E15.5 mouse의 두개골을 이용하여 in vitro 실험을 시행하였다. 흥미롭게도 osteogenic fronts 및 시상봉합부의 간엽조직 중앙에 FGF2-soaked beads를 점적하여 36시간 기관배양한 결과, bead주위 조직들의 두께 및 세포수가 증가되었으며, osteogenic fronts 상에 FGF4 beads를 올려놓은 경우, 시상두개봉합부 중앙에 점적된 FGF4 beads나 BSA control beads에 비해, 골성장이 촉진되어 시상두개봉합부의 부분적인 소멸을 관찰할 수 있었다. 이와 더불어 FGF2 beads는 osteopontin 및 Msx1 유전자의 발현을 유도하였다. 이 결과들을 종합해 볼 때, FGF-mediated FGFR signaling이 발육중인 두개골과 두개봉합부에서 세포의 증식과 분화의 균형을 조절하는데 중요한 역할을 담당하고 있음을 시사해주고 있으며, 이 과정중 FGF signaling이 osteopontin 및 Msx1 유전자의 발현을 조절하므로써 막내골성장 및 두개봉합부의 유지기전에 기여할 것으로 사료된다.