Heat-activated 'grenades' developed to fight cancer


Heat-activated "grenades" filled with cancer-fighting drugs have been developed by scientists, in the latest step to treat the disease.

The creation of a heat-activated trigger to release the drugs has been hailed as a way to make sure cancerous, rather than healthy tissue is targeted.

The findings of two studies by a team based at the University of Manchester are due to be presented at the National Cancer Research Institute (NCRI) cancer conference in Liverpool next week.

The method of treatment would see small bubble-like structures called liposomes carry drugs around the body to a tumour where they explode at a heat level above body temperature.

By heating the tumour scientists were able to control when the liposomes released their drugs.

It is hoped the development, which has so far been tested using warm water baths and heating pads on mice, could pave the way for more treatment options.

Study author and professor of nanomedicine at the University of Manchester Kostas Kostarelos said the discovery could help reduce the damage to healthy cells which can be caused by other forms of treatment.

He said: "Temperature-sensitive liposomes have the potential to travel safely around the body while carrying your cancer drug of choice.

"Once they reach a 'hotspot' of warmed-up cancer cells, the pin is effectively pulled and the drugs are released. This allows us to more effectively transport drugs to tumours, and should reduce collateral damage to healthy cells.

"The thermal trigger is set to 42 degrees Celsius (107.6F), which is just a few degrees warmer than normal body temperature.

"Although this work has only been done in the lab so far, there are a number of ways we could potentially heat cancer cells in patients - depending on the tumour type - some of which are already in clinical use."

Professor Charles Swanton, chair of this year's NCRI conference, said the development builds on what is the "holy grail" of nanomedicine.

He said: "Finding ways to accurately direct the liposomes towards tumours has been a major challenge in targeted drug delivery.

"These studies demonstrate for the first time how they can be built to include a temperature control, which could open up a range of new treatment avenues.

"This is still early work but these liposomes could be an effective way of targeting treatment towards cancer cells while leaving healthy cells unharmed."