Heating targeted cancer drugs increases uptake in tumour cells
Manchester University team compared liposomes with and without the ability to actively target cancer cells
Scientists at Manchester University have found that gentle heating of targeted nano-sized drug parcels results in them being more effectively delivered to tumour cells – resulting in an improvement in survival rates.
One established method for the delivery of cancer chemotherapy drugs has been to package them inside nano-sized containers, known as liposomes. This allows the drug to localise into cancer tissue more effectively and reduces side-effects by limiting drug-infused liposome uptake in healthy cells.
The effectiveness of these liposomes has been further improved by engineering them to contain molecules (monoclonal antibodies) on their surface that allow them to target cancer cells more effectively, as well as making them temperature-sensitive so that they release their drug content upon mild heating.
Researchers from the Nanomedicine Laboratory at The University of Manchester – part of the Manchester Cancer Research Centre – looked at the benefits of combining both active targeting and temperature-triggered release.
In combination with mild heating, the actively targeted liposomes showed greater uptake in tumour tissue in mice than those without this ability
Professor Kostas Kostarelos, who led the research, said: 'We have previously seen promising results from this combination approach on a petri dish, but no study had yet investigated its potential in living tissue.'
The team compared liposomes with and without the ability to actively target cancer cells. They found that in combination with mild heating, the actively targeted liposomes showed greater uptake in tumour tissue in mice than those without this ability. This resulted in a moderate improvement in the animals’ survival.
'We have successfully developed heat-activated and antibody-targeted liposomes to show that they are chemically and structurally stable. This approach may help us develop novel mechanistic strategies to improve targeted drug delivery and release within tumour tissue, while better sparing normal cells,' added Professor Kostarelos.
Full bibliographic information: “Monoclonal antibody-targeted, temperature-sensitive liposomes: In vivo tumor chemotherapeutics in combination with mild hyperthermia” Z S Al-Ahmady et al. Volume 196, 28 December 2014, Pages 332–343, Journal of Controlled Release.
