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Canine osteosarcoma is characterized by aggressiveness, easy metastasis to the lungs, and high mortality after standard therapy. Luteolin is a flavonoid found in vegetables and fruits and has diverse functions. Elucidation of the biological mechanisms of luteolin on canine osteosarcoma will enhance the efficacy of chemotherapeutic agents in canine tumors. In this study, we examined the effects of luteolin in the canine osteosarcoma cell lines, D17 and DSN. The results of this study show that luteolin inhibited canine osteosarcoma cell proliferation and induced apoptosis by altering cell-cycle proportion, producing reactive oxygen species, increasing the loss of mitochondrial membrane potential, and reducing cytosolic Ca2+ concentration. In addition, luteolin activated ERK1/2 and inactivated phosphoinositide 3-kinase/AKT signaling in canine osteosarcoma cells. Moreover, luteolin showed synergistic effects with cisplatin to reduce cell proliferation. In summary, luteolin induced cell death by initiating mitochondrial dysfunction and regulating intracellular signal transduction in canine osteosarcoma cells.  相似文献   

3.
Accumulating evidence suggested that transient receptor potential melastatin 2–antisense RNA (TRPM2-AS) played crucial roles in the progression of human cancers. However, the role of TRPM2-AS was still unknown in osteosarcoma. The aim of this study was to explore the clinical significance of TRPM2-AS in osteosarcoma patients, and determine the role of TRPM2-AS on osteosarcoma cell proliferation and apoptosis. In our results, we identified a novel oncogenic long noncoding RNA TRPM2-AS, which was overexpressed in osteosarcoma tissues and cells, and correlated with advanced Enneking stage, large tumor size and high histological grade in osteosarcoma cases. Survival analysis indicated that osteosarcoma patients with high TRPM2-AS expression had an obviously shorter overall survival time than those with low TRPM2-AS expression. Loss-of-function studies suggested that suppression of TRPM2-AS expression inhibited osteosarcoma cell proliferation and induced cell apoptosis through upregulating cleaved caspase-3 and cleaved caspase-9 expression. In conclusion, TRPM2-AS acts as an oncogenic long noncoding RNA and predicts poor prognosis in osteosarcoma.  相似文献   

4.
Osteosarcoma is the most bone-associated malignancy with high lethality. The current therapeutic strategy benefits little on the survival of patients. Studies have shown that aberrant activation of Wnt/β-catenin pathway is essential for the progression of osteosarcoma, implying that targeting this signaling may be an effective way of therapeutics. Recently, TIKI family has been identified as a new class of negative regulators for Wnt/β-catenin pathway. However, the implication of TIKIs with osteosarcoma has not been explored. Here, we constructed an adenoviral vector that expresses TIKI2 in osteosarcoma cells (Ad-TIKI2). TIKI2 expression was found to be reduced in osteosarcoma specimens and cell lines. In tested osteosarcoma cells, the activation of Wnt/β-catenin pathway was found to be inhibited by TIKI2 expression. Furthermore, the proliferation, colony formation ability, and invasion were all significantly suppressed in osteosarcoma cells infected with Ad-TIKI2. Finally, animal experiments further confirmed that TIKI2 restoration was able to inhibit the growth of osteosarcoma in vivo. Taken together, we provided evidence that reduced expression of TIKI family protein in osteosarcoma may participate in the progression of osteosarcoma and restoring its expression was able to impair the growth of osteosarcoma.  相似文献   

5.
We investigated the antitumor effect and mechanism of hematoporphyrin monomethyl ether-mediated photodynamic therapy (HMME-PDT) in sarcomas. Intracellular uptake of HMME by osteosarcoma cells (LM8 and K7) was time- and dose-dependent, while this was not observed for myoblast cells (C2C12) and fibroblast cells (NIH/3T3). HMME-PDT markedly inhibited the proliferation of sarcoma cell lines (LM8, MG63, Saos-2, SW1353, TC71, and RD) (P<0.05), and the killing effect was improved with increased HMME concentration and energy intensity. Flow cytometry analysis revealed that LM8, MG63, and Saos-2 cells underwent apoptosis after treatment with HMME-PDT. Additionally, apoptosis was induced after HMME-PDT in a three-dimensional culture of osteosarcoma cells. Hoechst 33342 staining confirmed apoptosis. Cell death caused by PDT was rescued by an irreversible inhibitor (Z-VAD-FMK) of caspase. However, cell viability was not markedly decreased compared with the HMME-PDT group. Expression levels of caspase-1, caspase-3, caspase-6, caspase-9, and poly (ADP-ribose) polymerase (PARP) proteins were markedly up-regulated in the treatment groups and increased with HMME concentration as determined by western blot analysis. In vivo, tumor volume markedly decreased at 7–16 days post-PDT. Hematoxylin and eosin staining revealed widespread necrotic and infiltrative inflammatory cells in the HMME-PDT group. Immunohistochemistry analysis also showed that caspase-1, caspase-3, caspase-6, caspase-9, and PARP proteins were significantly increased in the HMME-PDT group. These results indicate that HMME-PDT has a potent killing effect on osteosarcoma cells in vitro and significantly inhibits tumor growth in vivo, which is associated with the caspase-dependent pathway.  相似文献   

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Oxytocin stimulates proliferation of human osteoblast-like (hOB) cells and human osteosarcoma cells (SaOS-2). In contrast, oxytocin has also been shown to inhibit proliferation of other cell lines such as breast cancer cells.The aim of the present study was to investigate the effects of different concentrations of oxytocin on cell proliferation in osteosarcoma cell lines of different stages of differentiation: SaOS-2, TE-85, and UMR-106.For this purpose cells were incubated with oxytocin (1–1000  pmol/l). Cell proliferation was measured by [3H]thymidine incorporation and a commercially available kit (EZ4U).Incubation with oxytocin during 24  h increased proliferation of SaOS-2 cells significantly (100  pmol/l: p < 0.01). In contrast, 24  h of incubation with oxytocin decreased proliferation of TE-85 (100  pmol/l: p < 0.01) and UMR-106 cells significantly (100  pmol/l: p < 0.01). The effects of oxytocin in SaOS-2 and TE-85, but not in UMR-106 cells, were abolished when the cells were incubated with both oxytocin and an oxytocin antagonist (1-deamino-2-d-Tyr-(Oet)-4-Thr-8-Orn-oxytocin). Instead incubation with the oxytocin antagonist alone decreased proliferation of UMR-106 cells significantly (p < 0.001). Thus oxytocin has the capacity to both stimulate and inhibit cell proliferation of osteosarcoma cells. This effect might be dependent on the stage of differentiation of the cancer cells.  相似文献   

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Abstract

The pineal hormone, melatonin (MLT), has been shown to have therapeutic effects in patients with gastric cancer; however, the mechanisms for the anti-cancer effects are unknown. We investigated the effects of melatonin on cell proliferation, apoptosis, colony formation and cell migration in the gastric adenocarcinoma cell line, SGC7901, using MTT assay, Hoechst 33258 staining, flow cytometry, western blot, caspase-3 activity assay, soft agar colony formation assay, and scratch-wound assay. Our results showed that melatonin could inhibit cell proliferation, colony formation and migration efficiency, and it promoted apoptosis of SGC7901 cells. Our findings suggest that the anti-cancer effects of melatonin may be due to both inhibition of tumor cell proliferation and reduction of the metastatic potential of tumor cells.  相似文献   

9.
CCEPR (cervical carcinoma expressed PCNA regulatory lncRNA) has been found to be upregulated and enhance cell proliferation in human cancers. However, the role of CCEPR in osteosarcoma remains to be discovered. In this study, we found CCEPR expression was elevated in osteosarcoma tissue specimens and cell lines compared with adjacent normal tissue specimens and osteoblast cell line, respectively. Meanwhile, osteosarcoma patients with advanced stage or tumor size greater than 8 cm had higher expression of CCEPR than patients with early stage or tumor size less than or equal to 8 cm, respectively. Survival analysis suggested that osteosarcoma patients with high CCEPR expression had a worse overall survival rate than those with low CCEPR expression. The in vitro study indicated that CCEPR positively regulated proliferating cell nuclear antigen (PCNA) expression in osteosarcoma cells and silencing of CCEPR inhibited osteosarcoma cell proliferation through decreasing PCNA expression. In conclusion, CCEPR is a potential prognostic predictor and functions as oncogenic long non-coding RNA (lncRNA) to regulate cell proliferation via PCNA in osteosarcoma.  相似文献   

10.
Neoadjuvant chemotherapy in osteosarcoma improves the survival dramatically, but there is currents drug resistance in about 25% of patients, leading researchers to investigate alternative therapy forms. Suramin has in the last two decades been used as salvage therapy in some cancers. This study was undertaken to investigate suramin as a possible salvage therapy in osteosarcoma. The effect of suramin on three human osteosarcoma cell lines (MG-63, HOS and SaOS-2) and three primary osteosarcoma cell lines isolated from biopsies was investigated. Suramin significantly inhibited cell proliferation, determined by 3H-thymidine incorporation, of osteosarcoma cells at a dose ranging from 250 to 500 microg/ml. Suramin decreased the secretion of alkaline-phosphatase after stimulation by 1,25-dihydroxy-Vitamin D(3) up to 50% and decreased telomerase activity by up to 40%. The data demonstrate that suramin has marked in vitro effects on human osteosarcoma cells supporting further clinical investigation.  相似文献   

11.
SASH1, a member of the SLY-family of signal adapter proteins, is a candidate tumor suppressor in breast and colon cancer. The SASH1 protein possesses both the SH3 and SAM domains, indicating that it may play an important role in intracellular signal transduction. Reduced expression of SASH1 is closely related to tumor growth, invasion, metastasis, and poor prognosis. However, the biological role of SASH1 remains unknown in osteosarcoma. To unravel the function of SASH1, we explored the expression of SASH1 in osteosarcoma tissues and its correlation to the clinical pathology of osteosarcoma and analyzed the relationship between SASH1 expression and cell cycle, apoptosis and invasion of osteosarcoma MG-63 cells, using the flow cytometry analysis and transwell invasion chamber experiments. Furthermore, the effect of SASH1 on the expression of cyclin D1, caspase-3, matrix metalloproteinase (MMP)-9 were observed by western blot. Our results showed that the expression rate of SASH1 mRNA in osteosarcoma tissues was significantly lower than that in normal bone tissue (p = 0.000), that the expression rate of SASH1 mRNA in the carcinoma tissues from patients with lung metastasis was significantly lower than that from patients without lung metastasis (p = 0.041), and that the expression rate of SASH1 mRNA also decreased with increasing Enneking stage (p = 0.032). However, the mRNA expression of SASH1 in osteosarcoma was independent of the patient’s gender, age, and tumor size (p = 0.983, 0.343, 0.517, respectively). The SASH1 protein displayed a down-regulation in osteosarcoma tissues compared to normal bone tissue (p = 0.000), displayed a down-regulation in osteosarcoma tissues from patients with lung metastasis compared to from patients without lung metastasis (p = 0.000), and displayed a gradual decrease with increasing Enneking stage (p = 0.000). In addition, the MG-63 cells from pcDNA3.1-SASH1 group exhibited significantly reduced cell viability, proliferation, and invasive ability compared to the empty vector group and blank control group (p = 0.023, 0.001, respectively), and there was no difference between the empty vector group and blank control group. The pcDNA3.1-SASH1 group displayed significantly more apoptotic cells than the empty vector group and blank control group (p = 0.004). The expression of cyclin D1, MMP-9 displayed a down-regulation in MG-63 cells from pcDNA3.1-SASH1 group compared to the empty vector group and blank control group (p = 0.000, 0.001, respectively) and the expression levels of caspase-3 displayed an up-regulation in MG-63 cells from pcDNA3.1-SASH1 group compared to the empty vector group and blank control group (p = 0.000). Taken together, these data indicated that the overexpression of SASH1 might be associated with the inhibition of growth, proliferation, and invasion of MG-63 cells and the promotion of apoptosis of MG-63 cells.  相似文献   

12.
The physiological and pathological roles of dopamine D1 receptors (DR1) in the regulation of functions in tissues and organs have been recognized. However, whether DR1 are expressed in the osteosarcoma cells and inhibit the proliferation of these cells is unknown. In the present study, we found that DR1 were expressed in the osteosarcoma cells (OS732 cells). SKF-38393 (DR1 agonist) and the overexpression of DR1 decreased the proliferation of OS732 cells; SCH-23390 (DR1 antagonist) and the knockdown of DR1 increased the proliferation of OS732 cells, and both SCH-23390 and the knockdown of DR1 abolished the effect of SKF-38393 on the proliferation of OS732 cells. In addition, SKF-38393 down-regulated the phosphorylation of ERK1/2, PI3K, and Akt; SCH-23390 up-regulated the phosphorylation of ERK1/2, PI3K, and Akt, and SCH-23390 cancelled the effect of SKF-38393. The effect of SKF-38393 on the phosphorylation of ERK1/2, PI3K, and Akt and the proliferation of OS732 cells was similar to PD98059 (an ERK inhibitor) or LY294002 (a PI3K inhibitor), respectively. In conclusion, our results suggest that DR1 are expressed in the osteosarcoma cells and inhibit the proliferation of osteosarcoma cells by the down-regulation of the ERK1/2 and PI3K-Akt pathways. These findings provide a novel target for the treatment of the osteosarcoma.  相似文献   

13.
The oncogene c-Jun has been found to be up-regulated in a variety of cancers including osteosarcoma. DNA enzymes (DNAzymes) are oligonucleotides capable of specific catalysis of target mRNA. A c-Jun DNAzyme inhibited the growth and metastasis of osteosarcoma in an orthotopic spontaneously metastasizing model of the disease. c-Jun down-regulation-mediated apoptosis in osteosarcoma cells involved caspase-1, caspase-2, and caspase-8, but not the Fas/FasL pathway. Clinically, knockdown of c-Jun with DNAzymes may proffer an improved treatment outcome for these tumors originating in bone.  相似文献   

14.
Salinomycin (Sal) is a polyether ionophore antibiotic that has recently been shown to induce cell death in various human cancer cells. However, whether salinomycin plays a functional role in nasopharyngeal carcinoma (NPC) has not been determined to date. The present study investigated the chemotherapeutic efficacy of salinomycin and its molecular mechanisms of action in NPC cells. Salinomycin efficiently inhibited proliferation and invasion of 3 NPC cell lines (CNE-1, CNE-2, and CNE-2/DDP) and activated a extensive apoptotic process that is accompanied by activation of caspase-3 and caspase-9, and decreased mitochondrial membrane potential. Meanwhile, the protein expression level of the Wnt coreceptor lipoprotein receptor related protein 6 (LRP6) and β-catenin was down-regulated, which showed that the Wnt/β-catenin signaling was involved in salinomycin-induced apoptosis of NPC cells. In a nude mouse NPC xenograft model, the anti-tumor effect of salinomycin was associated with the downregulation of β-catenin expression. The present study demonstrated that salinomycin can effectively inhibit proliferation and invasion, and induce apoptosis of NPC cells in vitro and inhibit tumor growth in vivo, probably via the inhibition of Wnt/β-catenin signaling, suggesting salinomycin as a potential candidate for the chemotherapy of NPC.  相似文献   

15.
BackgroundOsteosarcoma is the most common type of primary malignant bone tumor. This disease has exhibited a progressively lower survival rate over the past several decades, which has resulted in it becoming a main cause of death in humans. Rosmarinic acid (RA), a water-soluble polyphenolic phytochemical, exerts powerful anticancer effects against multiple types of cancer; however, its potential effects on osteosarcoma remain unknown. Hence, the present study investigated the efficacy of RA against osteosarcoma and aimed to clarify the mechanisms underlying this process.MethodsThe effects of RA on cell viability, apoptosis, cell cycle distribution, migration, invasion, and signaling molecules were analyzed by CCK-8 assay, flowcytometric analysis, wound healing assay, Transwell assay, proteomic analysis, and use of shRNAs.ResultsRA exerted anti-proliferation and pro-apoptotic effects on U2OS and MG63 osteosarcoma cells. Apoptosis was induced via extrinsic and intrinsic pathways by increasing the Bax/Bcl-2 ratio, triggering the intracellular production of reactive oxygen species (ROS), reducing the mitochondrial membrane potential (MMP), and upregulating the cleavage rates of caspase-8, caspase-9, and caspase-3. Additionally, RA suppressed the migration and invasion of osteosarcoma cells by inhibiting the expression levels of matrix metalloproteinase-2 and -9 (MMP-2 and -9), which are associated with a weakening of the epithelial-mesenchymal transition (EMT). Moreover, proteomic analyses identified DJ-1 as a potential target for RA. Several studies have indicated an oncogenic role for DJ-1 using knockdowns via the lentiviral-mediated transfection of shRNA, which caused the conspicuous suppression of cell proliferation, migration, and invasion as well as the arrest of cell cycle progression. At the molecular level, the expression levels of DJ-1, p-PI3K, and p-Akt were reduced, whereas the protein levels of phosphatase and tensin homologue (PTEN) were increased.ConclusionIn conjunction with the high levels of DJ-1 expression in osteosarcoma tissues and cell lines, the present results suggested that RA exhibited anticancer effects in osteosarcoma cells by inhibiting DJ-1 via regulation of the PTEN-PI3K-Akt signaling pathway. Therefore, DJ-1 might be a biological target for RA in osteosarcoma cells.  相似文献   

16.
Prostaglandin (PG) A2 has been reported to inhibit the growth or induce apoptosis of various tumor cells. In the present study, PGA2 inhibited the growth of HL-60 cells and concomitantly-induced nuclear condensation and DNA fragmentation, characteristics of apoptosis. Down-regulation of c-myc mRNA, and activation of caspase-3 were observed in the PGA2 -treated cells. PGA2-induced DNA fragmentation was completely abolished in the presence of zVAD-Fmk or zDEVD-Fmk. But, relative cell survival was not improved up to that of untreated cells by pretreatment of caspase inhibitors, and c-myc down-regulation was not recovered by caspase inhibitors, either. Moreover, cytochrome c release and activation of caspase-9 was also observed in apoptotic cells and a specific inhibitor of caspase-9 (zLEHD-Fmk) prevented both DNA fragmentation and activation of caspase-3, but not relative cell survival, implying the upstream mitochondrial event of caspase-3 activation. In addition, antagonistic Fas antibody (ZB4) exerted no effect on the apoptosis. Taken together, these results suggest that PGA2 may induce the apoptosis as well as growth inhibition in HL-60 cells, and cytochrome c release and caspase activation seem to play a critical role in this apoptosis which might be independent or downstream of growth inhibition associated with c-myc down-regulation.  相似文献   

17.
MicroRNAs (miRNAs, miR) are of critical importance in growth and metastasis of cancer cells; however, the underlying functions of miRNAs in osteosarcoma (OS) remain largely unknown. This study was aimed to elucidate the role of miR-221 in regulating the biological behavior of OS cells. The proliferation ability was examined by cell counting kit-8 (CCK-8) and cell cycle assay. The abilities of cell migration, invasion, and apoptosis were monitored by transwell assay and flow cytometry, respectively. The effect of miR-221 on cyclin-dependent kinase inhibitor 1B (CDKN1B) expression was evaluated by luciferase assays, real-time polymerase chain reaction, and Western blot analysis. We found that miR-221 was elevated in OS cell lines compared with the normal osteoblastic cell line. Transfection of the miR-221 inhibitor into MG63 and U-2OS cell lines obviously suppressed cell proliferation, migration, and invasion, which is accompanied with cell cycle arrest in G0/G1 phase. Furthermore, luciferase reporter assays indicated that CDKN1B is directly targeted by miR-221 in OS cells. Knockdown of CDKN1B inhibited the effects of miR-221 inhibitor, along with decreased Bax and caspase-3 and increased cyclin E, cyclin D1, Bcl-2, Snail, and Twist1 expression. The results suggested that miR-221 might act as a potentially useful target for treatment of OS.  相似文献   

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Background

Chemoresistance is the principal reason for poor survival and disease recurrence in osteosarcoma patients. Inosine 5′-monophosphate dehydrogenase type II (IMPDH2) encodes the rate-limiting enzyme in the de novo guanine nucleotide biosynthesis and has been linked to cell growth, differentiation, and malignant transformation. In a previous study we identified IMPDH2 as an independent prognostic factor and observed frequent IMPDH2 overexpression in osteosarcoma patients with poor response to chemotherapy. The aim of this study was to provide evidence for direct involvement of IMPDH2 in the development of chemoresistance.

Methodology/Principal Findings

Stable cell lines overexpressing IMPDH2 and IMPDH2 knock-down cells were generated using the osteosarcoma cell line Saos-2 as parental cell line. Chemosensitivity, proliferation, and the expression of apoptosis-related proteins were analyzed by flow cytometry, WST-1-assay, and western blot analysis. Overexpression of IMPDH2 in Saos-2 cells induced strong chemoresistance against cisplatin and methotrexate. The observed chemoresistance was mediated at least in part by increased expression of the anti-apoptotic proteins Bcl-2, Mcl-1, and XIAP, reduced activation of caspase-9, and, consequently, reduced cleavage of the caspase substrate PARP. Pharmacological inhibition of IMPDH induced a moderate reduction of cell viability and a strong decrease of cell proliferation, but no increase in chemosensitivity. However, chemoresistant IMPDH2-overexpressing cells could be resensitized by RNA interference-mediated downregulation of IMPDH2.

Conclusions

IMPDH2 is directly involved in the development of chemoresistance in osteosarcoma cells, suggesting that targeting of IMPDH2 by RNAi or more effective pharmacological inhibitors in combination with chemotherapy might be a promising means of overcoming chemoresistance in osteosarcomas with high IMPDH2 expression.  相似文献   

20.
目的:研究三氧化二砷(As203)对人肝癌细胞SMMC-7721的促凋亡作用及对Smac、caspase-9、caspase-3表达的影响。方法:人肝癌细胞SMMC-7721经As20,处理,共分为四组,分别为空白对照组、低剂量组、中等剂量组、高剂量组。分别采用MTT、Hoechst33258染色法、Annexin V-FITC/PI双染法观察其对SMMC.7721细胞增殖的抑制,凋亡细胞核的形态学变化,以及诱导凋亡作用;采用Westemblot法检测凋亡相关蛋白Smac、caspase-9、caspase-3表达的变化。结果:MTT显示:As203在体外能明显抑制SMMC-7721的生长,具有时间剂量依赖关系,与空白对照组相比,其余三组细胞生存率明显下降,差异均有统计学意义(P〈0.05);Hoechst33258显示细胞呈明显的凋亡细胞形态学特征,具有剂量依赖性;AnnexinV-FITC/PI双染法显示:As203作用24小时可诱导SMMC-7721细胞凋亡,且呈剂量依赖性,与空白对照组相比(2.69±0.58),其余三组(4.01±0.58)、(5.99±1.69)、(9.26±2.34)差异均有统计学意义(P〈0.05);Westernblot显示:As2O3作用SMMC-7721细胞24小时,Smac、caspase-9、caspase-3表达上升,呈剂量依赖性,与空白对照组相比,其余三组蛋白表达量明显增加,差异均有统计学意义(P〈0.05)。结论:-定量的As203能抑制SMMC-7721细胞增殖,促进其凋亡,其机制可能与调控Smac、caspase-9、caspase-3表达有关。  相似文献   

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