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1.
Introduction: Pamidronate is used to treat metastatic bone lesions in human cancer patients. By directly inhibiting the mevalonate pathway, pamidronate disrupts GTPase‐binding protein prenylation, resulting in osteoclast apoptosis. Pamidronate has been demonstrated to exert dose‐ and time‐dependent cytotoxic effects in several canine malignant osteoblastic cell lines. However, the exact cytotoxic mechanism remains speculative. The purpose of this study was to investigate and characterize the molecular mechanism of pamidronate‐induced cytotoxicity in canine malignant osteoblasts. Methods: The involvement of farnesyl or geranylgeranyl pyrophosphate synthase inhibition was evaluated by performing rescue experiments with cells incubated for 48 hours with cytotoxic concentrations of pamidronate (50 and 100 μM), with or without farnesol (FOH) and geranylgeraniol (GGOH). Cell lysates were fluorometrically‐assessed for caspase‐3‐like activity (R&D Systems) following incubation with varying concentrations of pamidronate (control, 50 and 100 μM) for 48 hours. The expression of a prenylated GTPase protein, Rap1 A, was qualitatively evaluated with immunoblotting using a polyclonal goat antibody (Santa Cruz Biotechnology) in cells incubated for 48 hours with varying concentrations of pamidronate (0, 1, 10, 50, and 100 μM). Results: In cells treated with lower cytotoxic concentrations of pamidronate (50 μM) for 48 hours, the addition of GGOH, but not FOH, was able to diminish the degree cytotoxicity, p ≤ 0.05. However, cells incubated with higher cytotoxic concentrations of pamidronate (100 μM), neither GGOH nor FOH were able to reduce the level of pamidronate‐induced cytotoxicity. Caspase‐3‐like activity directly correlated with the degree of pamidronate‐induced cytotoxicity. Cells treated with pamidronate at 50 μM and 100 μM increased caspase‐3‐like activity by 5.3 and 7.1‐fold, respectively over untreated controls. The detection of Rap1A by immunoblotting requires further optimization. Conclusions: Pamidronate‐induced cytotoxicity in canine osteosarcoma cells may share a similar mechanism as has been demonstrated for osteoclasts. Inhibition of the mevalonate pathway appears to contribute to the observed cytotoxicity at lower doses of pamidronate. In addition, caspase‐3‐like activity contributes to the apoptotic process induced by pamidronate in malignant canine osteoblasts. 相似文献
2.
Investigation of the effect of pamidronate disodium on the in vitro viability of osteosarcoma cells from dogs 总被引：4，自引：0，他引：4
Ashton JA Farese JP Milner RJ Lee-Ambrose LM van Gilder JM 《American journal of veterinary research》2005,66(5):885-891
OBJECTIVE: To determine the effect of pamidronate disodium on the in vitro viability of osteosarcoma cells and non-neoplastic cells from dogs. SAMPLE POPULATION: 3 osteosarcoma and 1 fibroblast cell lines derived from dogs. PROCEDURE: Cell counts and cell viability assays were performed in cultures of osteosarcoma cells (POS, HMPOS, and COS31 cell lines) and fibroblasts after 24, 48, and 72 hours of incubation with pamidronate at concentrations of 0.001 to 1000 microM or with no drug (control treatment). Percentage viability was determined in cell samples for each concentration of pamidronate and each incubation time. A DNA fragmentation analysis was performed to assess bisphosphonate-induced apoptosis. RESULTS: Osteosarcoma cell viability decreased significantly in a concentration- and time-dependent manner at pamidronate concentrations ranging from 100 to 1000 microM, most consistently after 48 and 72 hours' exposure. In treated osteosarcoma cells, the lowest percentage cell viability was 34% (detected after 72 hours' exposure to 1000 microM pamidronate). Conversely, 72 hours' exposure to 1000 microM pamidronate did not significantly reduce fibroblast viability (the lowest percentage viability was 76%). After 72 hours of exposure, pamidronate did not cause DNA fragmentation in POS or HMPOS cells. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicate that pamidronate may have the potential to inhibit osteosarcoma growth in dogs, possibly through a nonapoptotic mechanism. The clinical relevance of these in vitro findings remains to be determined, but administration of pamidronate may potentially be indicated as an adjuvant treatment in chemotherapeutic protocols used in dogs. 相似文献
3.
Hong SH Mochizuki M Nishimura R Sasaki N Kadosawa T Matsunaga S 《Research in veterinary science》2000,68(1):57-62
The effect of two retinoids, all- trans and 9- cis retinoic acid, on the differentiation of three canine osteosarcoma cells (OOS, HOS, and POS) was examined using markers specifically expressed by phenotypic osteoblasts. Both retinoids induced morphologic differentiation in all the canine osteosarcoma cells. Retinoids enhanced cell flattening and spreading, as well as reduction in cell overlapping. Alkaline phosphatase (ALP) activity and ALP staining was enhanced in OOS, and HOS cells, but decreased in POS cells. These results may suggest that OOS and HOS cells have immature osteoblastic properties and POS cells have mature osteoblastic properties. Retinoids decreased osteocalcin production in all the osteosarcoma cells. They induced an increase in production of type I collagen in HOS and POS cells, but a decrease in OOS cells. These results indicate that retinoids induce differentiation of canine osteosarcoma cells, resulting in an altered expression of their malignant phenotype. 相似文献
4.
5.
Li SH Guo DZ Li B Yin HB Li JK Xiang JM Deng GZ 《Veterinary journal (London, England : 1997)》2009,179(3):430-436
This study investigated the effect of exogenous insulin-like growth factor (IGF)-1 on the proliferation and differentiation of osteoblastic cells from Chinese Holstein cattle and the resultant bone nodule formation and mineralisation in vitro. The osteoblastic cells were isolated and cultured, then identified using Giemsa and alkaline phosphatase (ALP) staining methods. The effect of different concentrations of IGF-1 on cell growth was assessed by MTT assay. The ALP activity and osteocalcin (OC) concentration in the osteoblastic cells were measured by a colorimetric assay and a radioimmmunoassay, respectively. Calcium nodules were observed using alizarin red S stain, while the content of matrix calcium was determined by atomic absorption spectrophotometry. Cell proliferation in the cultures was stimulated by IGF-1 at concentrations ranging from 1 to 200 ng/mL, with the maximum effect observed at 100 ng/mL. This effect was observed from day 1 and peaked at day 5, but decreased at day 7. At concentrations of 10 ng/mL and 100 ng/mL, IGF-1 significantly induced ALP activity, OC level, matrix calcium content, and nodule formation of the osteoblastic cells by 20–180% (P < 0.05 or P < 0.01), compared to controls. The results suggested that IGF-1 is an anabolic agent for the proliferation, differentiation, mineralisation and calcium content of dairy cow osteoblasts, and could therefore act as a potential treatment for the metabolic bone diseases in these animals. 相似文献
6.
H. I. Lacoste T. M. Fan L. P. de Lorimier S. C. Charney 《Veterinary and comparative oncology》2004,2(2):104-105
Introduction: Dogs with appendicular osteosarcoma (OSA) excrete higher concentrations of urine cross‐linked N‐telopeptide of type I collagen (NTx) than normal dogs. NTx is a specific biochemical marker of osteoclastic activity. Pamidronate is a bone‐modulating agent that exerts potent inhibitory effects on osteoclasts. The use of pamidronate is currently being evaluated for the management of osteolytic bone pain in dogs with appendicular osteosarcoma. Despite pamidronate's increasing usage in veterinary oncology, optimal dosing has yet to be determined. Commonly utilized dosages range from 1–2 mg/kg, given intravenously (IV) as a 2‐hour constant rate infusion every 28 days. The purpose of this prospective study was to compare the biological activity of two pamidronate doses (1 mg/kg vs. 2 mg/kg) in the suppression of urine NTx excretion in normal dogs and dogs with appendicular osteosarcoma. Methods: Seventeen OSA dogs receiving single‐agent pamidronate as palliative therapy were evaluated. Group 1A (n = 10) received a dose of 1 mg/kg and group 2A (n = 7) received a dose of 2 mg/kg IV. Urine NTx level were measured at day 0 and 28 using a commercial ELISA (Ostex International). Urine NTx level were also measured in 6 normal dogs: Group 1B (n = 3) received a dose of 1 mg/kg and group 2B (n = 3) received a dose of 2 mg/kg. In normal dogs, urine NTx levels were recorded weekly for six consecutive weeks. Results: In dogs with osteosarcoma, greater reductions in urine NTx excretion from baseline values were demonstrated at 2 mg/kg versus 1 mg/kg (57% and 23%, respectively). Likewise, in normal dogs, urine NTx excretion was suppressed to a greater extent with a dosage of 2 mg/kg versus 1 mg/kg (69% and 23%, respectively). Conclusion: Pamidronate possesses biologic activity in both normal dogs and in dogs with osteosarcoma, as assessed by reductions in urine NTx excretion. Based upon reductions in urine NTx excretion, a dosage of 2 mg/kg appears more effective than 1 mg/kg. 相似文献
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T.M. Fan S.C. Charney L.P. de Lorimier L.D. Garrett D.J. Griffon W.J. Gordon-Evans J.M. Wypij 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2009,23(1):152-160
Background: Canine osteosarcoma (OSA) causes focal malignant osteolysis leading to severe pain. Despite the documented efficacy of radiotherapy or IV aminobisphosphonates for managing cancer bone pain, their potential combined therapeutic value has not been reported in OSA-bearing dogs.
Hypothesis: Pamidronate combined with standardized palliative therapy will improve pain control and bone biologic effects in OSA-bearing dogs.
Animals: Fifty dogs with appendicular OSA treated with standardized palliative therapy and either pamidronate or sterile saline.
Methods: Randomized, prospective, double-blinded, placebo-controlled study. Treatment responses for dogs receiving standardized palliative therapy with (n = 26) or without (n = 24) adjuvant pamidronate were serially evaluated for changes in subjective pain scores, urine N-telopeptide (NTx) excretion, primary tumor relative bone mineral density ( r BMD), and computerized pressure platform gait analysis.
Results: Median duration of subjective pain relief for dogs treated with adjuvant pamidronate or placebo was 76 and 75 days, respectively ( P = .39). Forty percent (20/50; pamidronate [11/26] and placebo [9/24]) of dogs experienced durable analgesia, defined by pain alleviation ≥112 days. For patients achieving durable pain control, dogs treated with pamidronate achieved greater reductions in NTx excretion and larger increases in r BMD compared with placebo controls. Changes in peak vertical force assessed by computerized pressure platform gait analysis correlated with pain alleviation in OSA-bearing dogs.
Conclusions and Clinical Importance: Combining pamidronate with standardized palliative therapy is safe, but does not clearly improve pain alleviation. However, in dogs achieving durable pain control, adjuvant pamidronate appears to decrease focal bone resorption in the local tumor microenvironment. 相似文献
Hypothesis: Pamidronate combined with standardized palliative therapy will improve pain control and bone biologic effects in OSA-bearing dogs.
Animals: Fifty dogs with appendicular OSA treated with standardized palliative therapy and either pamidronate or sterile saline.
Methods: Randomized, prospective, double-blinded, placebo-controlled study. Treatment responses for dogs receiving standardized palliative therapy with (n = 26) or without (n = 24) adjuvant pamidronate were serially evaluated for changes in subjective pain scores, urine N-telopeptide (NTx) excretion, primary tumor relative bone mineral density ( r BMD), and computerized pressure platform gait analysis.
Results: Median duration of subjective pain relief for dogs treated with adjuvant pamidronate or placebo was 76 and 75 days, respectively ( P = .39). Forty percent (20/50; pamidronate [11/26] and placebo [9/24]) of dogs experienced durable analgesia, defined by pain alleviation ≥112 days. For patients achieving durable pain control, dogs treated with pamidronate achieved greater reductions in NTx excretion and larger increases in r BMD compared with placebo controls. Changes in peak vertical force assessed by computerized pressure platform gait analysis correlated with pain alleviation in OSA-bearing dogs.
Conclusions and Clinical Importance: Combining pamidronate with standardized palliative therapy is safe, but does not clearly improve pain alleviation. However, in dogs achieving durable pain control, adjuvant pamidronate appears to decrease focal bone resorption in the local tumor microenvironment. 相似文献
9.
Barroga EF Kadosawa T Okumura M Fujinaga T 《Veterinary journal (London, England : 1997)》2000,159(2):186-193
The efficacy of 22-oxacalcitriol (OCT), calcitriol, cholecalciferol, all-trans retinoic acid (ATRA) and 9-cis retinoic acid (9-cis RA) to differentiate in vitro four clonal cells of the canine osteosarcoma cell line POS into cells having properties of a functionally mature osteoblast bone cell were investigated. The induction of intracellular alkaline phosphatase (ALP) activity, osteocalcin (GLA-OC) and type I collagen (PIP) production after 72 h treatment were used as markers of differentiation. At a concentration of 10(-8)M, OCT and calcitriol significantly induced all markers, and ATRA only the ALP of osteoblast, chondroblast and undifferentiated clonal cells. At the same concentration, 9-cis RA and cholecalciferol induced ALP of chondroblast and osteoblast cells, respectively; ATRA, 9-cis RA and cholecalciferol induced PIP of chondroblast and undifferentiated cells. None of the drugs significantly differentiated fibroblast cells. The ability of these agents to differentiate osteosarcoma cells into cells that exhibit properties of functionally mature osteoblastic bone cells may promote normal osteogenesis and reverse the loss of control of their differentiation. 相似文献
10.
Introduction: Cyclooxygenase‐2 (COX‐2) inhibitors are being used increasingly in cancer therapy. Although the effects of COX‐2 inhibitors have been evaluated extensively in carcinomas, less is known about their effects in sarcomas. Since the majority of dogs with appendicular osteosarcoma (OSA) are treated for pain with a non‐steroidal anti‐inflammatory drug (some COX‐2 selective) prior to definitive treatment, it is important to determine the effects that commonly used NSAIDS have on tumor cell growth.
Methods: Established canine osteosarcoma (POS, HMPOS and COS31) and canine fibroblast cell lines were maintained in culture under standard conditions. Cells were incubated with either deracoxib (1 uM to 500 uM) or piroxicam (1 uM to 1000 uM). Cell viability was assessed at 72 hours by cell counts and the MTT assay. The DNA fragmentation analysis was utilized to assess for apoptosis induction.
Results: Deracoxib concentrations ≥100 uM and piroxicam concentrations ≥500 uM significantly reduced mean cell viability of all three OSA cell lines (lowest cell viability percentages 20% and 32%, respectively). Deracoxib concentrations ≥250 uM and piroxicam concentrations ≥500 uM also reduced viability of fibroblasts; however, the cell viability percent was reduced to only 54% and 68%, respectively, of the control value. Exposure of OSA cells to cytotoxic concentrations of deracoxib and piroxicam did not result in DNA fragmentation.
Conclusions: Deracoxib and piroxicam demonstrated a cytotoxic effect on canine osteosarcoma cells. There was no evidence of apoptosis induction at the concentrations evaluated. Further investigation will need to be performed to determine whether either drug exhibits anti‐tumor effects in vivo . 相似文献
Methods: Established canine osteosarcoma (POS, HMPOS and COS31) and canine fibroblast cell lines were maintained in culture under standard conditions. Cells were incubated with either deracoxib (1 uM to 500 uM) or piroxicam (1 uM to 1000 uM). Cell viability was assessed at 72 hours by cell counts and the MTT assay. The DNA fragmentation analysis was utilized to assess for apoptosis induction.
Results: Deracoxib concentrations ≥100 uM and piroxicam concentrations ≥500 uM significantly reduced mean cell viability of all three OSA cell lines (lowest cell viability percentages 20% and 32%, respectively). Deracoxib concentrations ≥250 uM and piroxicam concentrations ≥500 uM also reduced viability of fibroblasts; however, the cell viability percent was reduced to only 54% and 68%, respectively, of the control value. Exposure of OSA cells to cytotoxic concentrations of deracoxib and piroxicam did not result in DNA fragmentation.
Conclusions: Deracoxib and piroxicam demonstrated a cytotoxic effect on canine osteosarcoma cells. There was no evidence of apoptosis induction at the concentrations evaluated. Further investigation will need to be performed to determine whether either drug exhibits anti‐tumor effects in vivo . 相似文献
11.
Amputation and chemotherapy are the mainstay of treatment for canine appendicular osteosarcoma (OSA). In vitro studies have demonstrated anti‐tumour activity of pamidronate against canine OSA. The purpose of this study was to assess the safety of adding pamidronate to standard post‐operative carboplatin chemotherapy in 17 dogs with appendicular OSA treated with limb amputation. Median disease‐free interval (DFI) and median survival time (MST) were evaluated as secondary endpoints. Incidence of side effects and treatment outcomes were compared to 14 contemporary control patients treated with carboplatin alone. There were no identified side effects to the pamidronate treatment. The median DFI for the study group was 185 days compared to 172 days for the control group (P = 0.90). The MST of the study group was 311 days compared to 294 days for the control group (P = 0.89). Addition of pamidronate to carboplatin chemotherapy for the treatment of canine appendicular OSA is safe and does not impair efficacy of standard carboplatin treatment. 相似文献
12.
E F Barroga T Kadosawa M Okumura T Fujinaga 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1999,61(4):361-367
Highly lung metastasizing model of canine osteosarcoma in nude mice was established from five subcutaneous implantation cycles of lung tumor deposits. The selection of cells with increased metastatic properties from the parent POS canine osteosarcoma cell line recovered medium sized and polygonal Highly Metastasizing POS cells (HMPOS). The doubling time of HMPOS and POS in culture averaged 30 +/- 1.2 hr and 32 +/- 1.3 hr respectively, and their cell growth patterns in vitro were comparable to their in vivo growth patterns. HMPOS cells produced more tumor deposits (> 20 nodules, > 1 -mm in diameter) of various sizes with replacement of lung tissues at 12 weeks after implantation. POS cells produced fewer and smaller lung deposits (< 10 nodules, 1-mm in diameter). Tumor size and number of metastatic tumor deposits showed a regular association. HMPOS cells developed an osteoblastic type of cellular differentiation subcutaneously and in the lungs. HMPOS micrometastasis along the alveolar walls and blood vessels at 4 weeks averaged 6-7 small tumor locus. Each micrometastatic locus contained an average of 5-7 tumor cells, and developed a pleomorphic osteoblastic type of cellular differentiation. An average of 4 macrometastatic nodules could be seen at 6 weeks, composed of an average of 23 tumor cells, 10 nodules at 8 weeks, 12 nodules at 10 weeks and 20 nodules at 12 weeks. These model provides an opportunity for the evaluation of new treatments against canine lung metastatic osteosarcoma in a nude mice model. 相似文献
13.
S. C. Charney T. M. Fan L. P. de Lorimier H. I. Lacoste 《Veterinary and comparative oncology》2004,2(2):99-100
Introduction: Dogs with osteosarcoma suffer intense bone pain. Conventional palliative treatment options include ionizing radiation with or without systemic chemotherapy. Intravenous pamidronate is a first‐line therapeutic agent in people with painful skeletal metastases and is currently being evaluated for the management of osteolytic pain associated with canine osteosarcoma. The theoretical combination of radiation and pamidronate for managing bone pain appears to be a rational treatment option, however, in vitro experiments demonstrating additive or supraadditve cytotoxic effects of these two modalities would further support the clinical institution of this novel combination therapy. The purpose of this study was to evaluate the in vitro cytotoxicity of ionizing radiation and pamidronate in a canine OSA cell line and to characterize the interaction between these two therapeutic modalities when used in combination. Methods: The canine osteosarcoma cell line, HMPOS, was subjected independently to varying doses of ionizing radiation (100 cGy, 300 cGy, 400 cGy, 600 cGy, 800 cGy, or 1000 cGy) or different concentrations of pamidronate (10, 25, 50, 66, 75, 100, 150, 200, and 250 μM). Cells were harvested following 48 hours of incubation and cell viability was assessed by flow cytometric analysis. Dose‐response curves were generated, and a theoretical ED50 for each treatment modality calculated. An ED50 isobologram was created to determine if different combinations of ionizing radiation and pamidronate (isoboles) would demonstrate subadditive, additive, or supraadditve cytotoxic effects. Results: The ED50 of ionizing radiation and pamidronate were 614 cGy and 65.3 μM, respectively. Of the six different isobole combinations evaluated, three produced supraadditve effects, one produced a subadditive effect, and two produced additive effects. Conclusions: Both ionizing radiation and pamidronate independently exert in vitro cytotoxic effects. Positive interactive effects can be generated, but only with specific isobole combinations. The results from this in vitro study support the use of specific combinations of ionizing radiation and pamidronate in order to maximize the cytotoxic properties of both treatment modalities. 相似文献
14.
Extravasation reactions associated with the administration of pamidronate: 11 cases (2008–2013) 
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下载免费PDF全文 B. A. Marker L. G. Barber C. A. Clifford S. S. Correa P. L. Thalhofer T. A. LaDue C. M. Mullin M. L. Sauerbrey C. C. Wood 《Veterinary and comparative oncology》2017,15(2):470-480
Pamidronate is a bisphosphonate drug widely utilized in veterinary oncologic practice for the palliation of malignant osteolysis. Pamidronate has not been previously reported to cause tissue injury upon extravasation in dogs. The medical records of 11 client‐owned dogs undergoing palliative treatment for primary bone tumors with known or suspected pamidronate extravasation reactions were reviewed. The majority of adverse events were low grade in nature, however in some cases, the reactions were severe and led to euthanasia in one instance. Time to complete resolution of lesions ranged from within several days to greater than one and a half months. Aside from the dog that was euthanized, no long‐term sequelae of extravasation were identified. Treatments employed to address the reactions varied widely. Pamidronate extravasation reaction appears to be an uncommon, but potentially serious complication of intravenous administration. 相似文献
15.
K Nozaki T Kadosawa R Nishimura M Mochizuki K Takahashi N Sasaki 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1999,61(6):649-656
Effects of 1,25-dihydroxyvitamin D3 (1,25(OH)2D3), recombinant human transforming growth factor (rhTGF)-beta 1 and recombinant human bone morphogenetic protein (rhBMP)-2 on differentiation in four different canine osteosarcoma cell lines (POS53B, 53C, 53D and 14A) were examined using markers specifically expressed by phenotypic osteoblasts. 1,25(OH)2D3 increased alkaline phosphatase (ALP) activity in one cell line, osteocalcin production in two lines and type I collagen production in three lines. RhTGF-beta 1 increased ALP activity in one clonal cell, osteocalcin production in one clonal cell and type I collagen production in two clonal cells. RhBMP-2 increased ALP activity in all clonal cells, osteocalcin production in two clonal cells and type I collagen production in three clonal cells. Thus, these agents induced differentiation in osteosarcoma cells at different efficacies. Electron microscopic study revealed that these agents increased cellular activity in all cell lines with no evidence of degeneration of cell organelle by drug cytotoxicity. In some cultures treated with either 1,25(OH)2D3 or rhBMP-2, apoptotic cells were observed. Based on the change in markers, rhBMP-2 and 1,25(OH)2D3 seemed to be more effective than rhTGF-beta 1. These agents are potential inducers of apoptosis. 相似文献
16.
Single-agent pamidronate for palliative therapy of canine appendicular osteosarcoma bone pain 总被引：1，自引：0，他引：1
Fan TM de Lorimier LP O'Dell-Anderson K Lacoste HI Charney SC 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2007,21(3):431-439
BACKGROUND: Canine appendicular osteosarcoma (OSA) causes focal bone destruction, leading to chronic pain and reduced quality-of-life scores. Drugs that inhibit pathologic osteolysis might provide additional treatment options for managing cancer-induced bone pain. Aminobisphosphonates induce osteoclast apoptosis, thereby reducing pain associated with malignant osteolysis in human patients with cancer. HYPOTHESIS: Treatment of dogs with pamidronate administered intravenously will alleviate bone pain and reduce pathologic bone turnover associated with appendicular OSA in dogs. ANIMALS: Forty-three dogs with naturally occurring appendicular OSA administered pamidronate intravenously. METHODS: Prospective study. Therapeutic responses in dogs treated with pamidronate administered intravenously and nonsteroidal anti-inflammatory drugs (NSAID) were evaluated by using a numerical cumulative pain index score (CPIS), and by quantifying urine N-telopeptide (NTx) excretion and relative primary tumor bone mineral density (rBMD) assessed with dual energy x-ray absorptiometry. In addition, variables, including pamidronate dose, skeletal mass, baseline and change for CPIS, urine NTx and rBMD during treatment, and baseline tumor volume and radiographic pattern were compared between dogs clinically responsive and nonresponsive to pamidronate therapy. RESULTS: Twelve of 43 dogs (28%) had pain alleviation for >4 months, lasting a median of 231 days. Changes in CPIS and rBMD during treatment were statistically different between responders and nonresponders (P = .046 and .03, respectively). CONCLUSIONS AND CLINICAL IMPORTANCE: Substantiated by reductions in CPIS and increases in rBMD, single-agent pamidronate administered intravenously with NSAID therapy relieves pain and diminishes pathologic bone turnover associated with appendicular OSA in a subset of dogs. 相似文献
17.
L. P. Lorimier T. M. Fan S. C. Charney H. I. Lacoste D. A. Heller M. M. Endicott C. H. Souza 《Veterinary and comparative oncology》2004,2(2):101-102
Introduction: Palliative therapy is essential to improve the quality of life of dogs with osteosarcoma (OSA), when definitive therapy is not considered a valid option. Bisphosphonates, a novel class of antiosteoclastic drugs, are widely used in humans for several painful osteolytic conditions. Dual energy x‐ray absorptiometry (DEXA) is recognized as a reliable tool to measure bone mineral density (BMD), and to monitor treatment response to bisphosphonates in humans. A prospective evaluation of pamidronate, an injectable aminobisphosphonate, is ongoing in dogs with appendicular OSA. The potential value of DEXA for objective evaluation of BMD variations with palliative therapies is concurrently being assessed. Materials and Methods: Dogs with naturally occurring appendicular OSA treated with pamidronate constitute the patient population. A DEXA scan (QDR‐4500 W, Hologic, Bedford, MA) is performed on day 0 (baseline) and on every treatment day with pamidronate thereafter (every 28 days). For each dog, a whole body scan is performed, followed by a scan of the tumor, and contralateral normal bone. Three regions of interest are subsequently analyzed for BMD changes in tumor and normal bone. Statistical analysis was performed using Student t‐test and paired t‐tests, with significance being set at p < 0.05. Results: Nineteen dogs have been enrolled to date. Seven responders and 6 non‐responders have suitable data for analysis. A significant difference is observed (p = 0.04) between tumor BMD variations of responders and non‐responders at day 28 (mean variations +18.0% and ?4.6% respectively). The changes at day 28 are significant only in the responders (p = 0.038 vs p = 0.05 in non‐responders). When BMD of tumor and normal bone at day 84 is compared to day 0 in six responders, only tumor had a significant increase (p = 0.017 vs p = 0.279, respectively). Conclusions: Objective measurements of response to therapy are essential in pain palliation studies. Increased tumor bone BMD, as obtained by DEXA analysis, may correlate with subjective clinical improvement in pamidronate‐treated dogs with appendicular OSA. 相似文献
18.
Xiuxia Chen Yifeng Deng Zhenlei Zhou Qingshu Tao Jie Zhu Xiaolan Li Jinli Chen Jiafa Hou 《Veterinary research communications》2010,34(2):143-152
Medullary bone is a unique tissue in the long bones cavities of lay hens, and plays an important role as a calcium reservoir
for egg-shell formation. Medullary bone formation requires the synergistic action of estrogen and androgen on osteoblasts
during the early stage of sexual maturity. The objective of the current study was to investigate the effects of 17β-estradiol,
testosterone, and the combination on the proliferation, alkaline phosphatase (ALP) activity, apoptosis, the cell cycle of
chicken osteoblasts in vitro. The proliferation of osteoblasts was examined with the MTT assay. Apoptosis and the cell cycle
were assessed with flow cytometry. Either 17β-estradiol (200 pg ml−1) or testosterone (100 pg ml−1) or the combination (100 pg ml−1 each) significantly enhanced osteoblast proliferation and ALP activity, accelerated the osteoblast cell cycle, and stimulated
osteoblast DNA synthesis in a period of 24 h. 17β-estradiol, used alone or with testosterone, inhibited chicken osteoblast
apoptosis; However, testosterone alone induced cell apoptosis. In conclusion, 17β-estradiol combined with testosterone promoted
osteoblast proliferation and ALP activity, accelerated the osteoblast cell cycle, inhibited osteoblast apoptosis. 相似文献
19.
Rémi Froment Christian Bédard 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2016,45(3):459-465
This is the report of a 5‐year‐old male neutered Great Dane with an extreme leukocytosis (544.9 × 109 cells/L; RI 5.2–13.9 × 109 cells/L) characterized by highly atypical round cells. Cellular morphologic features such as cytoplasmic membrane blebs, a high nuclear‐to‐cytoplasmic ratio, and nuclear indentations and irregularities and large nucleoli, as well as immunocytochemistry for CD3 and CD79, myeloperoxidase cytochemistry, and clonality testing were not conclusive for myeloid or lymphoid origin. Marked alkaline hyperphosphatasemia was present at the first visit (2783.0 U/L; RI 6–80.0 U/L), followed by a 5‐fold increase (14,000 U/L) a week later, identified as being mostly contributed by the bone‐ALP isoform (11,062 U/L; RI 0–30 U/L). In addition, the atypical leukocytes were strongly positive for cytoplasmic ALP activity. In vitro lysis of a heparin blood sample resulted in a 1.7‐fold increase of ALP activity, supporting the origin of the hyperphosphatasemia at least in part from the leukemic cell population. To the authors’ knowledge, this is a unique case of alkaline hyperphosphatasemia, due at least to a leukemic cell population producing a bone‐ALP isoform, regardless of the exact nature of the leukemia. 相似文献
20.
J. K. McCleese M. D. Bear S. K. Kulp C. Mazcko C. Khanna C. A. London 《Veterinary and comparative oncology》2013,11(2):124-139
The receptor tyrosine kinase (RTK) Met is known to be over‐expressed in canine osteosarcoma (OSA). In human cancers, the RTKs Met, epidermal growth factor receptor (EGFR) and Ron are frequently co‐expressed and engage in heterodimerization, altering signal transduction and promoting resistance to targeted therapeutics. We found that EGFR and Ron are expressed in canine OSA cell lines and primary tissues, EGFR and Ron are frequently phosphorylated in OSA tumour samples, and Met is co‐associated with EGFR and Ron in canine OSA cell lines. Transforming growth factor alpha (TGFα) and hepatocyte growth factor (HGF) stimulation induced amplification of ERK1/2 and STAT3 phosphorylation in OSA cells and Met was phosphorylated following TGFα stimulation providing evidence for receptor cross‐talk. Lastly, treatment of OSA cells with combined gefitinib and crizotinib inhibited cell proliferation in an additive manner. Together, these data support the notion that Met, EGFR and Ron interact in OSA cells and as such, may represent viable targets for therapeutic intervention. 相似文献