Osteosarcoma is the most common type of bone cancer. It primarily affects children and younger adults. Survival rates have remained the same since the 1970s, averaging 53% to 55%. Of those who do survive, 50% have bone mass deficiencies, while 20% suffer from broken bones in weakened areas of their body. Researchers want to prevent these types of fractures, reduce recurrence, and strengthen bone structure to treat osteosarcoma survivors and boost their overall health.
Doctors currently treat osteosarcoma with surgeries for the tumors, cancer medications, and chemotherapy. However, there are side effects associated with cancer medications, such as nausea and vomiting. The chemicals and drugs used in chemotherapy can also harm the structure and function of the nervous system, causing neurotoxicity. Researchers have also reported drug resistance in common medications used for cancer treatment. Patients who fail to react positively to medication and chemotherapy have bleak outlooks, increasing the demand for newer treatments.
Researchers at Aston University College of Engineering and Physical Sciences may have identified a solution to these issues. The scientists combined biocompatible materials called bioactive glasses with gallium oxide to test how they interacted with cancer cells in the laboratory, or in vitro. Bioactive glasses are commonly used to regenerate bones and fix cavities, and are even found in some toothpastes.
The researchers gave cancerous cells bioactive glass with gallium oxide at amounts ranging from 1 to 5 mol% and monitored their growth daily for 10 days. They measured the percentage of cancerous cells that were killed during treatment, referred to as the treatment’s cytotoxicity. They used specialized cell counting equipment to measure the number of living and dead cells as well as the quantity that remained.
The researchers found that the 5 mol% gallium oxide bioactive glass successfully killed the cancerous cells over 10 days, reducing the viability of these cells by 99%, while keeping noncancerous human cells unharmed. On the first day, 80% to 100% of the cancerous cells were viable. After 5 days of treatment, 60% to 80% of the cancerous cells were viable, and after 7 days only 20% were viable.
The researchers confirmed that the gallium oxide reduced the viability of cancerous cells, rather than some other component of the bioactive glass, like sodium, calcium, silicon, or phosphorus. While the scientists determined that gallium oxide was the active component of the treatment, they still have to determine how to safely administer it, since this compound is harmful to humans if ingested. The scientists stated that it is more effective when taken as an injection rather than orally. However, they cautioned that gallium is excreted by the kidneys when administered as an injection, so this approach could cause renal toxicity.
The researchers concluded that new treatments based on bioactive glasses like this one could save many lives. They stated that their results “show significant potential for use in bone cancer applications as part of a multimodal treatment.” While future researchers should further test the use of bioactive glasses in cancer treatment, their initial results offer a positive way forward.
