New research by two separate teams at Western University is improving our understanding of breast cancer and leading towards better diagnosis and treatment.
Dr. John Weibe is unravelling a medical mystery at his Western lab, why some breast cancers don't respond to hormone-based treatments like tamoxifen.
"About half of breast cancers don't have these receptors - we call them receptor-negative breast cancers and there was no hormonal explanation."
Weibe and his team have identified hormones, once thought to be waste products, that in fact have the power to inhibit or stimulate tumour growth.
"The cancer-promoter hormone results in very rapid onset of tumours and very rapid growth - whereas the anti-cancer hormone supresses the growth," Weibe says.
Manipulating these hormones in mice produced dramatic results.
"The tumours grew so rapidly that we had to terminate them here…The cancer-suppressor hormone in blue - significantly supressed.”
The implications of the research are potentially huge, eventually in treating breast cancer and probably sooner than that in diagnosing breast cancer.
A short distance away on the Western campus, Dr. Shawn Li is looking at why some breast cancer cells don't respond to chemotherapy. The key is a missing protein called p53 that makes cancer cells tougher to kill.
"What we found is the p53 protein level is regulated by a protein called Numb. Numb would bond to p53 and protects it from being degraded in a cell - so without Numb p53 is quickly degraded in a cell.”
The hope is that by better understanding how what's happening in cells that are resistant to chemotherapy, more effective treatments will arise.
"We've basically identified a target pathway…to design something to modify the players in this pathway so we can manipulate the level of p 53 for the benefit of chemotherapy."
And it's possible the implications go beyond breast cancer to the way chemo reacts with other cancers.
