Feb 2 2012
Cancer-triggered drug
Finding a drug that targets only the diseased cells in our body and is otherwise harmless to healthy tissue is a goal for cancer researchers. It's driven the work of Professor Laurence Patterson, Director of the Institute of Cancer Therapeutics at the University of Bradford, and his team of researchers. The drug they are developing is based on Colchicine - a compound derived from the Autumn Crocus. The team believes this is the first attempt at removing existing blood vessel supply to a tumour. Using an enzyme, only found in diseased tissue as a trigger, means that it can also target secondary tumours caused by the cancer spreading through the body.
Their starting point was a batch of Matrix Metalloproteinases called MMP14, which had been identified in tumour tissue. This enzyme breaks down the proteins in surrounding healthy tissue and allows the tumour to proliferate. When the tiny molecules of the drug meet the MMP14 they combine to activate the drug.
Destroying cancer's lifeline
The tumour grows by getting its nutrients from the body. So if you can destroy the vasculator that the tumour has, then you starve it of oxygen and nutrients. Professor Patterson explains, 'we knew there were these disrupting agents but they weren't targeted. The ones that were being trialled would work where they were absorbed so one of the areas where their toxicity was high was the heart. These drugs hadn't progressed because of this. That's what's so exciting about what we have achieved. Every tumour that we have looked at expresses this enzyme MMP14 and the reason why they all express it is because all tumours that are confined within their original normal tissue environment need to break out of that environment, it's an enzyme that has benefit to all tumour types.'
Clinical trial
Although the chemical is a natural derivative, the team are making it in the laboratory. They have established proof of concept and once funding is established will embark on the next phase to develop the drug and set up a clinical trial.
The beauty of this drug, Patterson foresees, is its compatibility with conventional treatments such as chemotherapy. Given the resistant nature of tumours, Colchicine promises another weapon in the body's battle, cutting off the blood supply that allows the cancer to flourish, so even an aggressive cancer could be neutralised.