Objective  To provide new clinical ideas for the treatment of osteosarcoma, we analyzed clinical samples and constructed a cell transfection regulation model to examine the molecular mechanisms of parathyroid hormone type 1 receptor (PTHR1) that regulate osteosarcoma angiogenesis and proliferation.

  Methods  From January 2017 to December 2019, a total of 50 clinical samples taken from patients with classic osteosarcoma of the extremities confirmed by histopathology were examined at Cancer Hospital of Dalian University of Technology (Liaoning Provincial Cancer Hospital) and The Second People’s Hospital of Shenzhen (The First Affiliated Hospital of Shenzhen University). A PTHR1 silent osteosarcoma cell model was constructed, and differential expressions of PTHR1 in tumor tissue samples were analyzed to explore the correlation among PTHR1 expression levels, tumor proliferation, and patient survival rates. PTHR1 expression was downregulated in vitro to analyze its regulatory effect on angiogenesis.

  Results  In clinical samples of patients with osteosarcoma, PTHR1 expression in tumor tissues was significantly higher than that in adjacent tissues. Significant increases in PTHR1 expression were correlated with increases in tumor volumes and decreases in long-term survival rates. The 3-year cumulative survival rate of patients with high PTHR1 expression was lower than that of patients with low PTHR1 expression. Silencing PTHR1 expression in vitro effectively reduced the expression of vascular endothelial growth factor (VEGF), decreased tumor cells proliferation, and inhibited osteosarcoma angiogenesis in a chicken embryo yolk sac model.

  Conclusions  PTHR1 is highly expressed in tumor tissue and has a significant correlation with tumor proliferation and long-term survival rates. Inhibiting PTHR1 can reduce angiogenesis in osteosarcoma tissues.