Within 24 hours of gene therapy treatment boosted by nanoscale delivery to cancer cells, the tumours began to shrink, resulting in prolonged survival in all, and even cures in some cases
Cancer Research UK scientists have developed a system for treating hard-to-reach tumours, using nanoparticles to guide a 'tumour busting' gene to cancer cells.
The results of this study are published in the journal Cancer Research.
Scientists from Cancer Research UK's centre for oncology and applied pharmacology at the University of Glasgow, carried out laboratory tests on tumours of the cervix, bowel and other cells that line the body.
Within 24 hours of treatment, the tumours began to shrink, resulting in prolonged survival in all, and even cures in some cases.
The promising results of these experiments could make it possible to treat inaccessible tumours in humans using gene therapy in the future.
This new treatment can selectively target cancer cells, without causing damage to surrounding healthy cells.
Standard cancer treatment, such as chemotherapy, indiscriminately attacks all the cells in the region, which can lead to unpleasant side effects for patients.
Some tumours are inoperable, for example, if they are close to vital organs such as the heart or lungs.
Tumours that cannot be removed by surgery are commonly associated with a poor prognosis and survival.
In order to kill cancer cells at difficult tumour sites, gene medicines have to make an arduous journey through the body's blood vessels, where they have to travel across the vessel wall into the tumour and finally into the cancerous cell.
In this treatment, nanoparticles containing a combination of specially designed tiny molecules are used to transport a gene called TNF alpha to the affected cells.
The TNF alpha gene has a built-in switch that enables it to only become activated in cells that are cancerous.
TNF has highly toxic properties that cause cells to die, which is why it is crucial that it is only activated in cancer cells.
Andreas Schatzlein, lead researcher of the study, says: "Our research focussed on finding the right compounds to make the prospect of nanoparticle gene therapy a realistic treatment option.
"We found that the combination of an effective delivery system, along with the gene's clever ability to target cancer cells, is key to the success of this treatment.
"This is the first time that this type of treatment has been able to reduce the size of tumours to such an extent, so we hope to have further demonstrated the potential of genetic therapies to treat cancer in the future.
"Our efforts will now focus on understanding whether such systems can be used as a platform to deliver other genes and how to best harness the potential benefits to safely treat a broader range of tumours in the clinic".
Jim Cassidy, Cancer Research UK's director of medical oncology, says: "Gene therapy is a promising therapeutic approach that has been hampered by a lack of efficient and safe means of delivery.
"The fact that these experiments effectively destroyed the tumours in a lab setting is extremely encouraging news."
