How to turn on a cancer cell

A family of drugs being developed by scientists is designed to strip cancerous tumours of their immortality. As cancer develops, the timer controlling a cell's life span goes wrong allowing it to divide and multiply.

By turning the timer on again, Professor Stephen Neidle and Dr Lloyd Institute, Cancer Research, hope to send the cancer cells on a path of self-destruction.

Chromosomes and the genes that lie inside them control all aspects of a cell's life span. At the end of each chromosome is a special sequence of DNA matter that acts as a counter, getting shorter every time the cell divides. When the sequence reaches a certain critical point, the cell realises its time is up, stops growing and eventually self-destructs. This process helps to maintain a healthy balance between old and new cells.

A molecule called telomerase, present in 80% of cancer cells, is believed to rebuild the counter sequences.

Some drugs already modelled have proved very effective in blocking the action of telomerase. Further research is being undertaken in readiness for clinical evaluation and human trials.