Homing of mesenchymal stem cells (MSCs) to the defect site is indispensable for bone repair. Local endothelial cells (ECs) can recruit MSCs; however, the mechanism remains unclear, especially in the context of the inflammatory microenvironment. This study was aimed to investigate the role of ECs in MSCs migration during the inflammatory phase of bone repair. The inflammatory microenvironment was mimicked in vitro via adding a cytokine set (IL-1β, IL-6, and TNF-α) to the culture medium of ECs. The production of PDGF-BB from ECs was measured by ELISA. Transwell and wound healing assays were employed to assess MSCs migration toward ECs and evaluate the implication of PDGF-BB/PDGFRβ. A series of shRNA and pathway inhibitors were used to screen signal molecules downstream of PDGF-BB/PDGFRβ. Then, mouse models of femoral defects were fabricated and DBM scaffolds were implanted. GFP+ MSCs were injected via tail vein, and the relevance of PDGF-BB/PDGFRβ, as well as screened signal molecules, in cell homing was further verified during the early phase of bone repair. In the mimicked inflammatory microenvironment, MSCs migration toward ECs was significantly promoted, which could be abrogated by pdgfrb knockout in MSCs. Inhibition of Src or Akt led to negative effects analogous to pdgfrb knockout. Blockade of JNK, MEK, and p38 MAPK had no impact. Meanwhile, the secretion of PDGF-BB from ECs was evidently motivated by the inflammatory microenvironment. Adding recombinant PDGF-BB protein to the culture medium of ECs phenocopied the inflammatory microenvironment with regard to attracting MSCs, which was abolished by pdgfb, src, or akt in MSCs. Moreover, pdgfb knockout suppressed the expression and phosphorylation of Src and Akt in migrating MSCs. Src knockout impaired Akt expression but not vice versa. In vivo, reduced infiltration of CD31+ ECs was correlated with diminished PDGF-BB in local defect sites, and silencing pdgfb, src, or akt in MSCs markedly hampered cell homing. Together, these findings suggest that in the inflammatory microenvironment, MSCs migrate toward ECs via PDGF-BB/PDGFRβ and the downstream Src-Akt signal pathway.
The treatment of bone defects has always been a challenge for orthopedic surgeons. The development of tissue engineering technology provides a novel method for repairing bone defects and has been used in animal experiments and clinical trials. However, there are few clinical studies on comparing the long-term outcomes of tissue-engineered bones (TEBs) and other bone grafts in treating bone defects, and the long-term efficiency of TEBs remains controversial. Therefore, a study designed by us was aimed to compare the long-term efficacy and safety of individual tissue-engineered bones (iTEBs) and allogeneic bone granules (ABGs) in treating bone defects caused by curettage of benign bone tumors and tumor-like lesions. From September 2003 to November 2009, 48 patients who received tumor curettage and bone grafting were analyzed with a mean follow-up of 122 mo (range 60 to 173 mo). Based on implant style, patients were divided into groups of iTEBs ( n = 23) and ABGs ( n = 25). Postoperatively, the healing time, healing quality, incidence of complications, and functional scores were compared between the two groups. The Musculoskeletal Tumor Society functional evaluation system and Activities of Daily Living Scale scores were significantly improved in both groups with no significant difference. The average healing time of ABGs was longer than that of iTEBs ( P < 0.05). At the final follow-up, iTEBs had a better performance in the bone healing quality evaluated by modified Neer classification ( P < 0.05). In the group of iTEBs, the complication and reoperation rate was lower than that in the group of ABGs, with no tumorigenesis or immune rejection observed. In summary, for treating bone defects caused by tumor curettage, iTEBs were safe, effective, and tagged with more rapid healing speed, better healing outcome, and lower complication and reoperation rate, in comparison with ABGs.
To study and observe the safety and e cacy of anlotinib in the treatment of advanced osteosarcoma with metastases. We retrospectively studied patients with advanced osteosarcoma and metastases who received anlotinib treatment in our hospital from June 2018 to April 2020. All patients had received standard multimodal therapies, before taking anlotinib. Therapeutic doses of anlotinib were 12 mg for adults and 10 mg for children and adolescents once a day for 2 consecutive weeks, followed by a week of withdrawal. This 3-week cycle of treatment was continued until the tumor progressed rapidly or the patients failed to tolerate the side effects. Adverse drug reactions were recorded, and therapeutic e cacy was evaluated based on progression free survival (PFS), disease control rate (DCR), overall survival (OS), and objective response rate (ORR). The median PFS was 9.81 ± 0.9 months, and the 6-month and 10-month PFS rates were 73.3% and 33.3%, respectively. The median OS was 11.43 ± 0.58 months. No patients achieved complete response. After 6 months of treatment, the DCR and ORR were 80% and 13.3%, respectively. No drug-related deaths or Grade 4 adverse events occurred in the patients. Five patients (33.3%) had Grade 3 adverse events. The most common drug-related adverse events were hand-food syndrome, fatigue, high blood pressure, anorexia, and pneumothorax. Anlotinib had a certain curative effect on patients with advanced osteosarcoma and metastases after failure of standard treatment. The adverse events were mostly tolerable or relieved after treatment.
Background: The biologic bone reconstruction in the treatment of malignant bone tumours for the limb salvage surgery has always been a controversial strategie. Vary inactivation methods, convenient, stable, curative effect and economy need to be considered. This study aims to compare the clinical efficacy between intraoperative extracorporeal irradiated and alcohol inactivated autograft reimplantation methods for limb salvage surgery with osteosarcomas. Methods: We retrospectively analysed 28 patients with osteosarcomas, 14 patients treated with intraoperative cobalt 60 irradiation and reimplantation treatment (Group A), 14 patients treated by alcohol-inactivated autograft reimplantation (Group B). The postoperative complications and clinical efficacy was compared by statistical analysis. Results: The local recurrence rate was 14.3% in each group. Complete bony union was achieved in 64.3% in group A and 71.4% in group B. The overall 5-year survival rate was 71.4% in group A and 78.6% in group B. The mean MSTS score was 25.33 ± 4.72 (range 15–30 ) in group A and 24.00 ± 5.85 (range 15–30 ) in group B. The mean ISOLS score was 25.79 ± 5.13 (range 20–36 ) in group A and 26.14 ± 5.33 (range 20–30 ) in group B. P < 0.05 was considered to indicate a significant difference, there was no difference in the long-term clinical efficacy between the extracorporeal irradiation and alcohol-inactivated methods.Conclusions: For limb salvage surgery with osteosarcomas, either intraoperative extracorporeal irradiation or alcohol-inactivated autograft repimlantation had equivalent outcomes for biological reconstruction. The alcohol-inactivated technology could be a much more convenient and cheap treatment to reconstruct bone defects. Additional studies and more case studies are needed to fully evaluate the clinical efficacy and safety of the alcohol-inactivated surgical approach.
To study and observe the safety and efficacy of anlotinib in the treatment of advanced osteosarcoma with metastases. We retrospectively studied patients with advanced osteosarcoma and metastases who received anlotinib treatment in our hospital from June 2018 to April 2020. All patients had received standard multimodal therapies, before taking anlotinib. Therapeutic doses of anlotinib were 12 mg for adults and 10 mg for children and adolescents once a day for 2 consecutive weeks, followed by a week of withdrawal. This 3-week cycle of treatment was continued until the tumor progressed rapidly or the patients failed to tolerate the side effects. Adverse drug reactions were recorded, and therapeutic efficacy was evaluated based on progression free survival (PFS), disease control rate (DCR), overall survival (OS), and objective response rate (ORR). The median PFS was 9.81 ± 0.9 months, and the 6-month and 10-month PFS rates were 73.3% and 33.3%, respectively. The median OS was 11.43 ± 0.58 months. No patients achieved complete response. After 6 months of treatment, the DCR and ORR were 80% and 13.3%, respectively. No drug-related deaths or Grade 4 adverse events occurred in the patients. Five patients (33.3%) had Grade 3 adverse events. The most common drug-related adverse events were hand-food syndrome, fatigue, high blood pressure, anorexia, and pneumothorax. Anlotinib had a certain curative effect on patients with advanced osteosarcoma and metastases after failure of standard treatment. The adverse events were mostly tolerable or relieved after treatment.
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