Coming up with new drug delivery techniques that can precisely target cancer cells, while leaving healthy tissue unharmed, has been a major goal for cancer researchers in recent years. Scientists at the University of Manchester have been testing a new approach that relies on liposomes.
A liposome is a tiny bubble (vesicle), made out of the same material as a cell membrane. Liposomes can be filled with drugs, and used to deliver medications for treating cancer and other diseases. Membranes are usually made of phospholipids, which are molecules that have a head group and a tail group.
It’s not the first time these tiny, bubble-shaped structures have been used in drug delivery experiments. But the Manchester team says that they achieved their sought-after goal of using the liposomes to smuggle cancer drugs into cancer cells and then triggering their “drug grenades” by heating up the targeted tumors. The researchers tested this approach on tumors in the lab as well as mouse models for cancer, and they indicated that the liposomes could safely maneuver through the body without damaging healthy cells.
There are various methods that could be used to amp up the temperature of cancer cells. “The thermal trigger is set to 42 degrees Celsius, which is just a few degrees warmer than normal body temperature,” said Kostas Kostarelos, study author and professor of nanomedicine at the University of Manchester. “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 tumor type–some of which are already in clinical use.”
The studies were presented at the National Cancer Research Institute Cancer Conference in Liverpool. According too Professor Charles Swanton, chair of the 2015 NCRI Cancer Conference, using liposomes to deliver cancer medicines has been a holy grail of nanomedicine. But finding ways to accurately direct the liposomes towards tumors has been a major challenge in targeted drug delivery.
The new 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. While the research is still in the early stages, these liposomes could be an effective way of targeting treatment towards cancer cells while leaving healthy cells unharmed.