LONDON - Academic researchers working in collaboration with Antisoma plc have succeeded in harnessing as a potential cancer treatment the cyanide production system used by the cassava plant as a natural defense mechanism against insect pests.

When the plants are attacked by insects, the cellular disruption brings the enzyme linamarase into contact with a non-toxic sugar to produce cyanide and deter further attack.

The Antisoma system, dubbed AGENT (Antibody Guided Enzyme Nitrile Therapy), uses one of Antisoma's antibodies to target cancer cells, linked to a linamarase gene. In the second stage of the process, the non-toxic sugar is administered.

The system is able to specifically kill cancer cells by cyanide intoxication, according to Mahendra Deonarain of the Department of Biochemistry, Imperial College London, who carried out the research. One of the main advantages would be that cancer cells cannot develop resistance to cyanide.

The amount of cyanide generated by the technique is sufficient to kill only the specific cancer cells targeted by the antibody. The researchers are working to optimize the recombinant antibody/enzyme construct and expect to move into animal testing shortly.