Scope 47 - Can we treat cancer with bacteria?
20 April 2012, Cancer
The potential of using bacteria to treat cancer has long been recognised, but can we do so without having to first make the patient sicker?
In the late 1800s American surgeon Dr William Coley made the remarkable observation that erysipelas (Streptococcus pyogenes) infection in cancer patients coincided with a shrinking of their tumours. Coley then used a crude mixture of killed bacteria called Coleys toxins, to activate the immune systems of his cancer patients. His theory being that the immune responses elicited by the bacteria were equally capable of destroying tumour tissue. Although Coleys results were encouraging, there were serious problems with this approach, mostly concerned with how sick his patients got as a result of their treatment.
Fortunately science has progressed much since Coleys original experiments and controlled injection of mycobacteria is now a standard first line therapy for bladder cancer, although not without its complications.
In view of the varying, but promising, therapeutic activity of bacterial cell wall components in cancer therapy, efforts have been made to identify the molecules responsible for stimulating the anti-tumour immune responses.
Our Immunoglycomics team, led by Dr Bridget Stocker and Dr Mattie Timmer, were the first to determine how the length of a particular mycobacterial cell wall glycolipid influences the immune response. PhD student Ashna Khan was able to demonstrate this by synthesising a series of glycolipids of defined size and screening these against specific immune cells. Her work featured on the cover of the ChemBioChem journal at the end of last year due to its high scientific quality.
Ashna is now collaborating with Prof Franca Ronchese and Sabine Kuhn to develop safe versions of the immune-stimulating bacterial compounds for the treatment of cancer patients.
Pictured above: Ashna Khan