Objective To review the research progress of the treatment of osteosarcoma, and to thoroughly understand its current state of research and prospect so as to lay a sol id foundation for the cl inical treatment. Methods The cl inical and experimental research l iteratures about treatment of osteosarcoma were extensively reviewed and analyzed. Results The present treatment of osteosarcoma is still need to comprehensive therapy which combine chemotherapy and surgical treatment. There are some progresses in gene therapy and molecular targeting therapy which can improve survival rate. Furthermore, well-designed studies and cl inical trials are needed to evaluate the potential therapeutic impact before they are used in cl inical. Conclusion Advancement in chemotherapeutic regimens has improved survival and l imb-sparing surgery in the treatment of osteosarcoma, but the progress of gene therapy and molecular targeting therapy gives new hope for osteosarcoma patients.
Objective To assess the efficacy of high-dose chemotherapy versus moderate-dose chemotherapy in the treatment of osteosarcoma. Methods We searched MEDLINE, EMbase, OVID database, CBMdisc, Cochrane CENTRAL Register of Controlled Trials in The Cochrane Library, and handsearched Journal of Chinese Oncology, Journal of Chinese Clinical Oncology and Tumor. The search time was updated to Feburary 2006.The quality of the included studies was evaluated by two reviewers and meta-analyses were performed on the results of homogenous studies. Results Four studies involving 937 participants with primary, high-grade and non-metastatic extremity osteosarcoma were included. All the included studies were judged to be inadequate at reporting randomization and blinding, only one reported allocation concealment. All included studies reported the number of withdrawals and the reasons for these. The meta-analyses showed that there were no significant differences in 5-year event free survival (EFS) (RR 1.10, 95% CI 0.96 to1.25), 5-year overall survival (OS) (RR 1.08, 95% CI 0.97 to1.20), local recurrence rate (RR 0.92, 95% CI 0.54 to 1.57), proportion of good histological response (RR 0.93, 95% CI 0.81 to 1.07), proportion of limb salvage [RR 0.97, 95% CI 0.92 to 1.02) between the high-dose group and the moderate-dose group. The 5-year EFS of the good histological response group was significantly higher than in the poor histological response group [OR 2.45, 95% CI 1.76 to 3.39,Plt;0.00001 ). Conclusions No advantage is shown for high-dose chemotherapy over moderate-dose chemotherapy in 5-year EFS, 5-year OS, local recurrence rate, proportion of good histological response and proportion of limb salvage. Histological response to preoperative chemotherapy is an independent prognosis factor for osteosarcoma. Due to the potential risk of selection bias, performance bias and publication bias, the evidence is not b enough to judge whether high-dose chemotherapy is better than moderate-dose chemotherapy in the treatment of osteosarcoma. Our conclusion suggests that large-scale randomized trials should be performed.
Objective To investigate the effect of limb salvage on treating osteosarcoma with pathological fracture. Methods From October 2002 to January 2003, 2 cases of osteosarcoma with pathological fracture were treated by limb salvage. Intraarterial chemotherapy was given by subcutaneous implantable delivery system with caffeine. Replacement with prosthesis was performed after 5 times of chemotherapy. Results Two patients were followed up for twenty-four months and 21 months respectively. No infection, aseptic loosening, local recurrence or metastasis occurred, and function recovery of joints was satisfactory. Conclusion Limb salvage can be considered in condition that primary osteosarcoma with pathological fracture can be treated by effective and comprehensive chemotherapy.
Exosomes are a type of tiny vesicles released by cells, which contain bioactive molecules such as proteins, nucleic acids, and lipids secreted by cells. Exosomes released by different cells play an important role in tumor development and metastasis. These exosomes can regulate the tumor microenvironment, promote the tumor growth and invasion, and participate in the process of distant metastasis by carrying specific proteins and nucleic acids. In addition, some biomarkers in exosomes can serve as potential biomarkers for early diagnosis and prognosis evaluation of osteosarcoma. This article reviews the research progress of exosomes in osteosarcoma, aiming to gain a deeper understanding of their mechanisms of action in this disease and provide a reference for the development of new treatment strategies and prognostic evaluation indicators.
ObjectiveTo investigate the effects of cinobufagin on the apoptosis in U-2OS osteosarcomas cells (U-2OS cells) and explore its potential mechanism. MethodsThe cytostatic effects of cinobufagin (10, 20, 50, 100, 200, and 400 nmol/L) on U-2OS cells were evaluated by MTT assay at 24, 48, and 72 hours after culture; simple U-2OS cells served as control group. The impact of cinobufagin (100 nmol/L) on the apoptosis in U-2OS cells was determined by flow cytometry at 48 hours after culture, which were treated with cinobufagin (experimental group) or with cinobufagin plus Z-VAD-FMK (control group), and simple U-2OS cells served as blank control group. The Caspase-3 activity was measured by Caspase-3 activity assay kit at 48 hours after culture, which were treated with cinobufagin (20, 50, and 100 nmol/L), and simple U-2OS cells served as control group.The expression of apoptosis signal pathway related proteins in U-2OS cells treated with cinobufagin were detected by Western blot at 48 hours after culture, which were treated with cinobufagin (20, 50, and 100 nmol/L), and simple U-2OS cells served as control group. ResultsThe results of MTT assay showed that cinobufagin inhibited the proliferation of U-2OS cells in a dose- and time-dependent manners. At each time point, the growth rate of U-2OS cells was significantly reduced with the increasing cinobufagin concentration, and as time prolonged, the growth rate of U-2OS cells behaved the same way in the same group. There were significant differences among different time points and groups (P<0.05). The apoptotic rate of experimental group (46.87%±11.23%) was significantly higher than that of the control group (2.34%±0.98%) and blank control group (1.04%±0.25%) (P<0.05). The Caspase-3 activity in 20, 50, and 100 nmol/L groups were 1.14±0.32, 1.31±0.41, and 1.92±0.54, respectively, which were significantly higher than that in control group (P<0.05). Compared with 20 and 50 nmol/L groups, 100 nmol/L group significantly increased the Caspase-3 activity in U-2OS cells (P<0.05). Compared with the control group, the expressions of cleaved Caspase-3, cleaved Caspase-9, and Bax were obviously up-regulated; the Bcl-2 expression was down-regulated; and the ratio of Bax/Bcl-2 was increased in different cinobufagin-treated groups (P<0.05). The same tendency was seen in different cinobufagin-treated goups, showing significant differences among groups (P<0.05). ConclusionCinobufagin can inhibite the proliferation of U-2OS cells, and induce cell apoptosis. The potential mechanism of cinobufagin-induced apoptosis may be related to the mitochondria-mediated pathway.
Objective To investigate the possibility of using extendible distal femoral replacements in the treatment of osteosarcoma in growing individuals. Methods From December 1999 to March 2003, 3 cases (2 were typeⅡB, 1 was type ⅡA) with osteosarcoma were treated byextendible distal femoral replacements. Of the 3 cases, 2 underwent prosthesis extention operation, 1 was not operated. Results After the removal of tumor, the extremities of 2 patients were shortened by 4 to 5 cm within 2 to 3 years. After the lengthening procedure, the affected extremities were of equal length to the unaffected extremities and no drag symptoms of blood vessel and nerves were observed. Follow-up was done for 2 months to 3 years. There was no aseptic loosening. The function of joints was fairly good. Conclusion Extendible distal femoral replacements is an easy, convenient, and effective way to treat osteosarcoma.
Objective To investigate the effect of ursolic acid on the proliferation and apoptosis of human osteosarcoma cell line U2-OS and analyze its mechanism. Methods Human osteosarcoma cell line U2-OS was divided into 4 groups, which was cultured with ursolic acid of 0, 10, 20, and 40 μmol/L, respectively. At 0, 24, 48, and 72 hours after being cultured, the cell proliferation ability was detected by cell counting kit 8 (CCK-8). At 48 hours, the effects of ursolic acid on cell cycle and apoptosis of U2-OS cells were measured by flow cytometry. Besides, the expressions of cyclin D1 and Caspase-3 were detected by real-time fluorescent quantitative PCR and Western blot. Results CCK-8 tests showed that the absorbance (A) value of each group was not significant at 0 and 24 hours (P>0.05); but the differences between groups were significant at 48 and 72 hours (P<0.05). Flow cytometry results showed that, with the ursolic acid concentration increasing, the G1 phase of U2-OS cells increased, the S phase and G2/M phase decreased, and cell apoptosis rate increased gradually. There were significant differences between groups (P<0.05). Compared with the 0 μmol/L group, the relative expressions of cyclin D1 mRNA and protein in 10, 20, and 40 μmol/L groups significantly decreased (P<0.05); whereas, there was no significant difference in relative expression of Caspase-3 mRNA between groups (P>0.05). However, with the ursolic acid concentration increasing, the relative expressions of pro-Caspase-3 protein decreased and the relative expressions of activated Caspase-3 increased; there were significant differences between groups (P<0.05). Conclusion Ursolic acid can effectively inhibit the proliferation of osteosarcoma cell line U2-OS, induce the down-regulation of cyclin D1 expression leading to G0/G1 phase arrest, increase the activation of Caspase-3 and promote cell apoptosis.