Dissecting the effects of ²²³Radium on the bone microenvironment

Area of Science:

• Biomedical Engineering
• Radiology
• Oncology

Background:

• Radium-223 (²²³Ra) is an alpha-particle-emitting radionuclide used for metastatic prostate cancer.
• ²²³Ra accumulates in bone, but mechanisms of associated fracture risk are unclear.
• ²²³Ra's effects are localized due to alpha particle short range.

Purpose of the Study:

• To investigate the biological mechanisms of ²²³Ra-induced bone fragility.
• To clarify the effects of ²²³Ra on bone and bone stromal cells.

Main Methods:

• Micro-computed tomography
• Mechanical studies
• Ex vivo spatial biology analysis using 3D fluorescence microscopy

Main Results:

• ²²³Ra caused significant trabecular bone loss, sparing cortical bone.
• ²²³Ra impaired osteoblast activity, increased osteoclast numbers, and promoted adipocyte formation.
• Zoledronic acid prevented ²²³Ra-mediated trabecular bone loss.

Conclusions:

• ²²³Ra's impact on bone health involves multiple bone stromal cell components.
• ²²³Ra-induced bone fragility can be mitigated by zoledronic acid co-administration.