Currently, drugs known as bisphosphonates are used to treat patients who have bone cancer or osteoporosis. These drugs bind to the skeleton and prevent a loss in bone density. They remain bound to bones for months or even years after initial treatment.
However in some cases, cancer patients who receive high doses of a bisphosphonate drug during treatment experience jaw damage as a result of routine oral surgery. The presence of the bisphosphonates bound to the jawbone can cause painful and chronic inflammation and infection as a side effect of a common oral procedure such as tooth removal. This can lead to the loss of jawbone tissue. To compound the seriousness of the issue, there is no known way to either treat or prevent this potentially deadly side effect from occurring.
“When being treated for cancer, the infusion of the high dose bisphosphonate drug is an important tool to control bone pain and osteolysis in patients with cancers,” said Dr. Ichiro Nishimura, a professor of prosthodontics with the UCLA School of Dentistry and a member of the UCLA Jonsson Comprehensive Cancer Center. “These are cancers that originate in bone marrow, such as multiple myeloma, or that have metastasized to the skeleton, such as from breast and prostate cancers. The presence of this bisphosphonate represents a significant risk particularly following needed routine dental surgery.”
In a new pre-clinical research study published in Bone Science Direct, the researchers from UCLA, who collaborated with colleagues at USC, were able to remove the bisphosphonate drugs from the jawbone by injecting another kind of bisphosphonate compound that is inert and doesn’t have pharmacological effect. This technique displaced the bisphosphonate drug bound to the jawbone’s surface. The potential advantage of this technique in a clinical setting would allow the bisphosphonate drugs to remain bound to the rest of the skeleton and continuing to prevent bone loss, while being displaced from the jawbone and clearing the way for oral surgery.
UCLA researchers presented these findings at the American Society for Bone and Mineral Research annual meeting and the International Association for Dental Research annual meeting in 2017.
The UCLA team that contributed to this study include: Akishige Hokugo, Keiichi Kanayama, Shuting Sun, Kenzo Morinaga, Yujie Sun, QingQing Wu, Hodaka Sasaki, Hiroko Okawa, Courtney Evans and Ichiro Nishimura. The team also included: Charles McKenna of USC; and Frank Ebetino, Mark Lundy and Keivan Sadrerafi of BioVinc.
The UCLA Jonsson Comprehensive Cancer Center has approximately 500 researchers and clinicians engaged in cancer research, prevention, detection, control, treatment and education. One of the nation's largest comprehensive cancer centers, the UCLA Jonsson Comprehensive Cancer Center is dedicated to promoting research and translating basic science into leading-edge clinical studies.
