MIPS researchers discover new way to slow cancer spread

2 March 2016

New research by Monash University academics has revealed that existing, readily available anti-stress drugs could help fight cancer by slowing the rate and volume at which cancer cells spread through the body.

Cancer can spread via the lymphatic system, which generally helps carry immune cells throughout the body in order to fight illness. A new study by Dr Caroline Le and Dr Erica Sloan of the Monash Institute of Pharmaceutical Sciences, published in the prestigious journal Nature Communications, demonstrates that chronic stress alters lymphatic activity, which accelerates the spread of the cancer.

As Dr Le explains, chronic stress results in the development of "cancer highways" that allow cancer cells to travel more freely.

"We found that chronic stress signals through the sympathetic nervous system (SNS) – better known as the 'fight-or-flight' response – to profoundly impact lymphatic function and the spread of cancer cells," Dr Le says. "These findings demonstrate an instrumental role for stress in controlling lymphatic function to impact health."

Their initial findings that stress accelerates cancer's spread led Dr Le and Dr Sloan to ask whether anti-stress medication could help slow it down.

To answer that question, they collaborated with clinicians at the European Institute of Oncology in Milan. The Institute has a large database of cancer patients, and their analysis confirmed that the use of anti-stress drugs was in fact associated with less spread of cancer through lymphatic pathways.

Further imaging studies conducted by their clinical colleagues at the Peter MacCallum Cancer Centre in Melbourne investigated if anaesthetic agents that are routinely used during cancer surgery also could be used to block lymph flow. They found that common anaesthetic drugs that block SNS signaling also slow lymphatic flow. This suggests another strategy to control lymphatic function with the goal of preventing the spread of cancer cells.

The research is innovative not just in its findings, but in its methods. To accurately monitor the movement of tumour cells, researchers tagged the cells with a fluorescent marker and used state-of-the-art imaging techniques to directly visualise tumour cells that had spread into lymphatic vessels. The imaging indicated that stress can increase the number and size of lymphatic vessels in and around tumours, while also increasing the rate of fluid flow within these vessels.Dr Le led this research as part of her PhD studies. Ongoing studies in Dr Sloan's lab are investigating strategies that help patients manage the adverse effect of stress. In collaboration with clinicians from the Peter MacCallum Cancer Centre, the team is undertaking a clinical study of anti-stress drugs for cancer patients.