PURPOSE: This study was performed to evaluate the expressions of osteopontin (OPN) and clusterin in a transitional cell carcinoma (TCC) of the urinary bladder, and then compare their expression rates with the tumor invasiveness. MATERIALS AND METHODS: Twenty-five superficial and 25 invasive TCC were used for immunohistochemical staining. RESULTS: All 25 non-invasive TCC showed a strong positive reaction for OPN. Twenty of the invasive TCC showed a strong positive reaction for OPN, but 5 showed only a weak positive reaction. OPN expression was significantly decreased in the invasive TCC (p=0.02). Eighteen superficial TCC showed a weak positive reaction for clusterin, with 7 showing a negative reaction. Nine invasive TCC showed a strong positive reaction for clusterin, and 11 showed only a weak positive reaction. Five invasive TCC showed a negative reaction for clusterin. Clusterin expression was significantly increased in the invasive TCC (p=0.001). CONCLUSIONS: These results may suggest that OPN and clusterin could be used as markers to predict the biological behavior of a TCC.
Carcinoma, Transitional Cell* ; Clusterin* ; Osteopontin* ; Urinary Bladder*

PURPOSE: This study was aimed at evaluating the histological changes of new bone and expression of osteopontin (OPN) after mandibular distraction osteogenesis. MATERIALS AND METHODS: Unilateral mandibular distraction (0.5 mm twice per day for 10 days) was performed in eight adult dogs. Two animals were sacrificed at 7, 14, 28 and 56 days after completion of distraction, respectively. The distracted bones and contralateral non-distracted control bones were harvested and processed for histological and immunohistochemical examinations. RESULTS: The new bone was arranged to tension direction after distraction osteogenesis. 7 days after distraction, numerous osteoblasts lining the immature trabecular bone and fibroblast-like cells in the fibrous intrezone were observed. 14 days after distraction, the new formed trabecular bones were thickened compared with 7 days after distraction. 28 days after distraction, the fibrous interzone was almost filled with newly calcified bone, and it was more hardened at 56 days after distraction. Increased OPN signals detected in the osteoblasts lining the trabecular bone and fibroblast-like cells in the fibrous interzone at 7 and 14 days after distraction. At 28 days after distraction, the OPN was weakly expressed in the osteoblasts, and it was not detected in all cellular components of distracted bone at 56 days later of distraction. CONCLUSIONS: After distraction osteogenesis, the distracted zone was completely calcified during the 56 days of consolidation period. In this study, the staining intensity of OPN increased in the osteoblasts and fibroblast-like cells at 7 and 14 days after distraction. The expression pattern of this protein shown here suggested that OPN play an important role in the osteogenesis during the early consolidation period.
Adult ; Animals ; Dogs ; Humans ; Osteoblasts ; Osteogenesis ; Osteogenesis, Distraction* ; Osteopontin*

BACKGROUND: Although basal cell carcinoma (BCC) is the most common human skin tumor, with calcification reportedly taking place in about 20% of all BCC cases, the pathogenesis of calcification in BCC has not yet been studied. OBJECTIVE: The purpose of this study was to evaluate factors related to the pathogenesis of calcification in BCC. METHODS: We performed immunohistochemical staining for beta-catenin, frizzled-2, BMP-4, osteopontin, osteocalcin, and osteonectin using frozen skin tissue from 15 cases of BCC with calcification and 11 cases of BCC without calcification. RESULTS: The expression of beta-catenin showed positive in 14 of the 15 cases in BCC with calcification, but negative in all 11 cases of BCC without calcification. The expression of frizzled-2 was observed in 14 of the 15 cases in BCC with calcification, and in 10 of the 11 cases in BCC without calcification. The difference did not reach statistical significance (p=0.236). The expression of BMP-4 was observed in all 26 samples of BCC, but the intensity of expression did not reach statistical significance between the two groups (p=0.293). Furthermore, osteopontin and osteocalcin showed no statistical significance between two the groups (p=0.567, p=0.401). The expression of osteonectin was observed in all of the BCC cases, and was stronger in BCC with calcification than in BCC without calcification (p=0.042). CONCLUSION: We suggest that the calcification in BCC might be related to the increase of beta-catenin expression and that osteonectin might also influence the process of calcification in BCC.
beta Catenin* ; Carcinoma, Basal Cell* ; Humans ; Osteocalcin* ; Osteonectin* ; Osteopontin* ; Skin

Coronary Restenosis ; metabolism ; Heart Valve Diseases ; Humans ; Osteopontin ; metabolism

Osteopontin(OPN) is a secreted phosphoprotein that is expressed constitutively in the descending thin limb(DTL) and papillary surface epithelium (PSE). Although the function of OPN is not known with certainty, it has been suggested that OPN may play a role in the regulation of calcium-mediated or calcium-dependent processes. The aim of this study was to compare the effects of 1,25-dihydroxyvitamin D3(VitD), parathyroid hormone(PTH) and calcitonin, the hormones involved in the regulation of calcium homeostasis, on renal OPN expression. Three groups of rats were studied:1)acute(single injection of VitD, 200ng/100g BW s.c., 12h before sacrifice) and chronic VitD(daily injection of VitD 50ng/day/100g BW s.c. for 7d). 2) acute(single injection of PTH 50 microgram/100g BW i.p., 30min before sacrifice) and chronic PTH(infusion of PTH 6 microgram/day/100g BW s.c., for 7d via miniosmotic pump). 3) acute(single injection of calcitonin 25U/100g BW i.p., 1h before sacrifice) and chronic calcitonin(infusion of calcitonin 0.2U/ hr/kg BW s.c., for 7d via miniosmotic pump). Each of the study was compared with vehicle-treated animals. Kidneys were processed for immunohistochemistry and OPN expression was examined using a monoclonal antibody to OPN. In vehicle-treated animals, OPN was expressed primarily in DTL and PSE. In the acute VitD and PTH groups, OPN immunoreactivity appeared strongly in proximal tubule, and increased slightly in DTL and PSE. In the chronic VitD and PTH groups, there was a marked increase in OPN immunoreactivity in DTL, PSE, distal convoluted tubule(DCT) and thick ascending limb(TAL) of Henle's loop. Calcitonin groups showed no apparent change. In summary, this study demonstrates that OPN is constitutively expressed in the cells of the DTL and PSE, and induced in proximal tubule(PT), DCT and TAL by vitD and PTH. From these results we conclude that vitD and PTH play an important role in regulation of OPN expression not only in DTL and PSE but also in PT, DCT and TAL.
Animals ; Calcitonin* ; Calcium ; Epithelium ; Homeostasis ; Immunohistochemistry ; Kidney* ; Osteopontin* ; Rats* ; Vitamin D* ; Vitamins*

Osteopontin (OPN) is a secreted glycoprotein that is expressed in various tissues, including brain, and mediates a wide range of cellular activities. In a previous study, the authors observed the robust neuroprotective effects of recombinant OPN and of RGD and SLAYGLR-containing OPN-peptide icosamer (OPNpt20) in an animal model of transient focal ischemia, and demonstrated anti-inflammatory and pro-angiogenic effects of OPNpt20 in the postischemic brain. In the present study, we investigated the effects of OPNpt20 on the motility and phagocytic activity of BV2 cells (a microglia cell line). F-actin polymerization and cell motility were significantly enhanced in OPNpt20-treated BV2 cells, and numbers of filopodia-like processes increased and lamellipodia-like structures enlarged and thickened. In addition, treatment of cells with either of three mutant OPN icosamers containing mutation within RGD, SLAY, or RGDSLAY showed that the RGD and SLAY motifs of OPNpt20 play critical roles in the enhancement of cell motility, and the interaction between exogenous OPNpt20 and endogenous αv and α4 integrin and the activations of FAK, Erk, and Akt signaling pathways were found to be involved in the OPNpt20-mediated induction of cell motility. Furthermore, phagocytic activity of microglia was also significantly enhanced by OPNpt20 in a RGD and SLAY dependent manner. These results indicate OPNpt20 containing RGD and SLAY motifs triggers microglial motility and phagocytic activity and OPNpt20-integrin mediated signaling plays a critical role in these activities.
Actins ; Brain ; Cell Movement ; Glycoproteins ; Ischemia ; Microglia* ; Models, Animal ; Neuroprotective Agents ; Osteopontin* ; Phagocytosis ; Polymerization ; Polymers

OBJECTIVE: To evaluate the effects of both exogenous and endogenous osteopontin on normal and malignant ovarian epithelial cell growth, and on paclitaxel chemo-resistance. METHODS: The ovarian cancer cell line OV429, which showed low level of endogenous osteopontin and paclitaxel sensitive cell line OV420, which showed high level of endogenous osteopontin, and a normal ovarian epithelial (HOSE: Human ovarian surface epithelial) cells were treated with purified osteopontin. Furthermore, OV420 was treated with osteopontin siRNA alone or in combination with paclitaxel. Proliferation rates and cell cycle progression of treated cells were determined by the tetrazolium colorimetric (XTT) assay and FACS analysis, respectively. RESULTS: Exogenous osteopontin increased the proliferation rate of OV429 and OV420 but had negligible effect on normal HOSE. Ovarian cancer cell lines treated with siRNA showed significantly reduced the growth rates (P<0.05), and they were arrested in G2/M phase of the cell cycle. Furthermore, OV420 treated with paclitaxel in the presence of osteopontin siRNA showed significantly decreased the survival rate. CONCLUSION: Osteopontin promote cell growth in malignant but not in normal ovarian epithelial cells, and may confer paclitaxel-resistance by adhesion to each cell and minimized the cell surface which exposure to chemo-agents.
Cell Cycle ; Cell Line ; Epithelial Cells* ; Humans ; Osteopontin* ; Ovarian Neoplasms ; Paclitaxel ; RNA, Small Interfering ; Survival Rate

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-E1 cells. MATERIALS AND METHODS: When MC3T3-E1 osteoblastic cells had reached 70-80% confluence, cultures were transferred to a differentiating medium supplemented with 5 mM 2-DG or 10 micrometer 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.
Calcification, Physiologic ; Deoxyglucose ; Gene Expression ; Osteoblasts ; Osteonectin ; Osteopontin ; Quercetin ; RNA, Messenger

PURPOSE: Osteopontin is one of the major non-collagenous protein of hard tissue. Use of peptide domain of biologically active protein has some advantages. The objective of this experimental study is evaluation of periodontal regenerative potency of synthetic peptide gel which containing collagen binding domain of osteopontin in the degree III periodontal defect of beagle dogs. MATERIAL AND METHODS: Experimental degree III furcation defect was made in the mandibular third and fourth premolar of beagles. Regenerative material was applied during flap operation. 8 weeks after regenerative surgery, all animals were sacrificed and histomorphometric measurement was performed to calculate the linear percentage of the new cementum formation and the volume percentage of new bone formation. RESULT: The linear percent of new cementum formation was 41.6% at control group and 67.1% at test group and there was statistically significant difference. The volume percent of new bone formation was 52.1% at control group and 58.9% at test group. CONCLUSION: As the results of present experiment, synthetic peptide gel containing collagen binding domain of osteopontin significantly increase new bone and cementum formation in the degree III furcation defect of canine mandible.
Animals ; Bicuspid ; Collagen ; Dental Cementum ; Furcation Defects ; Mandible ; Osteogenesis ; Osteopontin ; Protein Structure, Tertiary ; Regeneration

PURPOSE: This study was undertaken to investigate the osteogenic induction potential of PGA & FBS mixture on a calvarial defect in the rabbit. METHODS: Twenty New zealand white rabbit, weighing from 3.5-4kg were allocated into each of the three groups. Four 8mm sized bone defects were made on the parietal bone by drilling. In group I, the bony defects were implanted with 50 micrometer thickness film containing mixture of PGA and FBS. In group II, with PGA only film, & in group III, the bony defects were left with no implants. Results were evaluated by using morphologic change, radiographic study, biochemical study and histologic examination at 1 week (group I n=7, group II n=7, group III n=14), 2 weeks (group I n=6, group II n=6, group III n=12) and 3 weeks (group I n=7, group II n=7, group III n=14) following implantation. RESULTS: In the morphologic & radiographic study, the formation and corticalization of callus were observed earlier in group I than in groups II and III (p<0.05). In histological examination, group I showed more abundant and faster new bone formation than in group II and III. In biochemical analysis, group I displayed more activity than in group II and III. Group I also showed more abundant osteopontin, osteocalcin than groups II and III. CONCLUSION: In conclusion, the results demonstrate that the mixture of PGA and FBS has an effect on osteoblastic formation in the rabbit model. It is considered that further evaluation of long term results on resorption, immunologic tissue reaction and response of applied mixture in the human model will be needed.
Bony Callus ; Humans ; New Zealand ; Osteoblasts ; Osteocalcin ; Osteogenesis ; Osteopontin ; Parietal Bone