Boffins have developed a new gene therapy by using 'suicide genes' derived from mesenchymal stem cells taken from human fat tissue, which hunt for and kill cancerous tumours.
The study was conducted by a team of researchers led by Cestmir Altaner at the Cancer Research Institute of the Slovak Academy of Sciences in Bratislava.
As part of the study to find a less toxic method than chemotherapy to treat colon cancer, researchers extracted the mesenchymal stem cells from human fat tissue, and after expanding their number in the lab, used a retrovirus vector to insert the gene cytosine deaminase into the cell.
The gene can convert a less toxic drug, 5-fluorocytosine (5-FC), used in chemotherapy, to 5-FU inside the stem cells, and the chemotherapy can then seep out into the tumour, producing a lethal by-stander effect.
Researchers first injected the engineered mesenchymal stem cells, then 5-FC in nude mice, animals with an inhibited immune system, engrafted with human colon cancer.
The study found that tumour growth was inhibited by up to 68.5 percent in the animals, and none of the mice exhibited any signs of toxic side effects.
"The procedure was quite effective even though we applied the stem cells just once. Obviously, repeated treatment will increase the efficacy, as would using this strategy in combination with other treatments," Altaner said.
Researchers suggested that mesenchymal stem cells 'see' a tumour as a damaged organ and migrate to it, and so it might be used as a 'vehicle' for treatment that can find both primary tumours and small metastases.
The findings of the study were published in the July 1 issue of Cancer Research, a journal of the American Association for Cancer Research.