Bone cancer. It’s not something you think about when you are a teenager. But for most osteosarcoma patients, the inevitable teenage growth spurt coincides with tumours developing in the bones around the knee, or in the upper arm bone close to the shoulder.
“Osteosarcoma patients often present with a lump in the bone that might be initially disregarded as a sports injury or growing pain,” Dr Hawkins explained. “By the time a diagnosis is made the cancer may have spread to the lungs. Thanks to advances in surgical techniques, amputation of an arm or a leg is often avoidable, but intensive chemotherapy is usually necessary.”
Chemotherapy can cure most patients whose tumours are localised within the bone where they arose, but it is often ineffectual for patients whose cancer cells have spread to their lungs.
In research funded by Tour de Cure, Dr Hawkins and colleagues are identifying alternatives to chemotherapy. They have discovered that a new class of anti-cancer drugs, known as Smac mimetics, can destroy osteosarcoma cells, even when they’re growing within the lungs.
“The drugs affect the way that cancer cells respond to a protein called TNFα, which is produced by particular immune cells that can infiltrate tumours,” Dr Hawkins said. “Under normal conditions, TNFα enables cancer cells to replicate and spread. But when Smac mimetics are introduced, the same encounter with TNFα causes the cancer cells to die.”
“Smac mimetics converts TNFα from acting as a pro-cancerous force for evil, into an anti-cancer force for good.”
“Using chemotherapy to treat osteosarcoma improved the five-year survival rate from 20% in the 1960s to 60% by the 1980s,” indicated Dr Hawkins. “Unfortunately there has been no significant improvement since. Our findings provide hope that Smac mimetics may enable more osteosarcoma patients to survive their cancers.”
Recent work from Dr Hawkins and her laboratory at LIMS – including contributions from PhD student, Michael Harris, has been published in Clinical & Experimental Metastasis. Dr Hawkins also featured on Channel 7 Sunrise program as part of the support provided by charity, Tour de Cure.