Scientists predict what a nano drug will do to a breast cancerFebruary 9th, 2009 - 2:38 pm ICT by IANS
Washington, Feb 9 (IANS) Scientists successfully predicted the outcome of a nano drug on breast tumours in a pre-clinical study. Their research could help determine which patients will respond best to cancer-fighting nano drugs.
The investigators used contrast agents encapsulated in tiny fat bubbles called liposomes to determine if breast tumours in rodents could be breached by liposomes loaded with a cancer drug called liposomal doxorubicin. The liposomes were administered intravenously.
When scientists X-rayed the rodents, they received good images of porous breast tumours which had absorbed the contrast agents. On the other hand, poor images indicated the contrast agents had not substantially penetrated the tumour.
When liposomal doxorubicin was administered, it was associated with better therapeutic results in the tumours with superior images.
“We can tell if the animals are candidates for the treatment or not,” said Ananth Annapragada, co-author of the study and associate professor at University of Texas School of Health Information Sciences, Houston. Researchers from the Georgia Institute of Technology and Emory University also participated in the study.
Higher uptake of the probe by the tumour, indicating leakier vasculature, was associated with a slower tumour growth rate, suggesting a better therapeutic outcome with liposomal doxorubicin, the authors wrote. A nanometer is a billionth of a metre and a liposome is about 100 nanometres.
Nano drugs for cancer like liposomal doxorubicin are designed to increase the amount of drug reaching tumours. Currently, when an intravenous cancer drug is administered, very little reaches its intended target. The remaining drug circulates in the bloodstream and can cause side-effects, said a Georgia release.
Liposomes carrying drugs infiltrate leaky tumours that have pores up to eight times the size of these miniaturized drug carriers. If a liposome with contrast agents can penetrate a tumour and be detected by X-rays, there is a good chance that a liposome with anti-cancer agents can enter the tumour, too.
The results appear in the February issue of Radiology.