Perioperative rh-endostatin with chemotherapy improves the survival of conventional osteosarcoma patients: a prospective non-randomized controlled study

An innovative staged prosthetic lengthening reconstruction strategy for osteosarcoma-related leg discrepancy

Correction of leg length discrepancy (LLD) in skeletally mature patients with osteosarcoma was rarely reported and quite challenging. This study aimed to propose a treatment strategy of staged lengthening and reconstruction with a standard static prosthesis to address LLD and restore limb function. It also evaluated the effectiveness of the strategy in terms of leg lengthening, functional outcomes, and complications. The strategy for lengthening included three stages. In stage 1, the previous prosthesis was removed and an external fixator with a temporary rod-cement spacer was placed. In this stage, the external fixator was used to lengthen the limb to the appropriate length. In stage 2, the external fixator was removed and the old rod-cement spacer was replaced with a new one. In stage 3, the rod-cement spacer was removed and the standard static prosthesis was planted. Nine skeletally mature distal femoral osteosarcoma patients with unacceptable LLD were treated in our institution from 2019 to 2021. We performed a chart review on nine patients for the clinical and radiographic assessment of functional outcomes, LLD, and complications. The mean (range) leg lengthening was 7.3 cm (3.6-15.6). The mean (range) LLD of the lower limbs decreased from 7.6 cm (4.1-14.2) before the lengthening to 0.3 cm (- 0.3 to 2.1) at the final follow-up with statistical significance (P = 0.000). The mean (range) Musculoskeletal Tumor Society score improved from 30.3% (16.7%-53.3%) before the lengthening to 96.3% (86.7%-100%) at the final follow-up with statistical significance (P = 0.000). Three patients (33.3%) had a minor complication; none needed additional surgical intervention. In the short term, the current staged lengthening and reconstruction with standard static prosthesis provided satisfactory functional outcomes and LLD correction with few complications. The long-term effects of this method need further exploration.

Current research progress in targeted anti-angiogenesis therapy for osteosarcoma

Osteosarcoma (OS) is the most common primary malignant bone tumour with a peak in incidence during adolescence. Delayed patient presentation and diagnosis is common with approximately 15% of OS patients presenting with metastatic disease at initial diagnosis. With the introduction of neoadjuvant chemotherapy in the 1970s, disease prognosis improved from 17% to 60%-70% 5-year survival, but outcomes have not significantly improved since then. Novel and innovative therapeutic strategies are urgently needed as an adjunct to conventional treatment modalities to improve outcomes for OS patients. Angiogenesis is crucial for tumour growth, metastasis and invasion, and its prevention will ultimately inhibit tumour growth and metastasis. Dysregulation of angiogenesis in bone microenvironment involving osteoblasts and osteoclasts might contribute to OS development. This review summarizes existing knowledge regarding pre-clinical and developmental research of targeted anti-angiogenic therapy for OS with the aim of highlighting the limitations associated with this application. Targeted anti-angiogenic therapies include monoclonal antibody to VEGF (bevacizumab), tyrosine kinase inhibitors (Sorafenib, Apatinib, Pazopanib and Regorafenib) and human recombinant endostatin (Endostar). However, considering the safety and efficacy of these targeted anti-angiogenesis therapies in clinical trials cannot be guaranteed at this point, further research is needed to completely understand and characterize targeted anti-angiogenesis therapy in OS.

Effect of endostatin on Wnt pathway of stem-like cells in bladder cancer in tumor microenvironment

Wnt/β-catenin signaling pathway modulates miscellaneous biological events in cells including gene expression, cell growth, apoptosis, metabolism and transition. The aim of this study was to investigate the effect of endostatin on Wnt signaling pathway of stem-like cells in bladder cancer in tumor microenvironment. The qRT-PCR assay and western blot were conducted to evaluate related factors expressions of Wnt signaling pathway in both bladder cancer 5637 cells and stem cells. Loss of function assays were carried out to detect the influence of endostatin on the proliferation, migration, cell proliferation and apoptosis of bladder cancer cells. We demonstrated that endostatin triggered the degradation of β-catenin, a key mediator of Wnt signaling. The activation of the endostatin blocked β-catenin function and inhibited cell growth and migration of bladder cancer. In order to verify that the Wnt/β-catenin signaling pathway was inhibited by endostain in 5637 bladder cancer cells and stem cells, the Wnt/β-catenin signaling pathway-associated molecules, including DKK1, LRP5, TCF4, β-catenin, cyclin D1, and c-Myc, were evaluated in 5637 bladder cancer cells and stem cells. The western blotting results showed that expressions of these molecules were remarkably increased in the 5637 bladder cancer cells and stem cells compared to the control group. In summary, our study demonstrated that endostatin inhibited angiogenesis. The downregulation of the Wnt/β-catenin pathway may be engaged in the suppression of angiogenesis by endostatin in bladder cancer cells and cancer stem cells.