The key to halting the rapid spread of lung cancer may be contained in four molecules that have been uncovered by scientists.

There's a desperate need for new treatments for lung cancers

Dr Michael Seckl

Dr Michael Seckl and his team at Imperial College and Hammersmith Hospital are investigating small cell lung cancer (SCLC) - a particularly fast growing form of the disease.

It affects around 10,000 people each year in the UK, and is notoriously difficult to treat and often becomes resistant to chemotherapy.

The team have identified vital molecules that help the disease grow and resist treatment.

They hope that their findings will open the way to designing more effective drugs, which are urgently needed.

Comes back

Dr Seckl said: "There's a desperate need for new treatments for lung cancers.

"This type of tumour grows incredibly fast and many patients are diagnosed when the disease is already widespread.

"Surgery is rarely an option, so we usually treat lung cancer patients using combinations of chemotherapy and radiotherapy."

Dr Seckl said that often the disease seems to disappear, and scans look clear.

However, the cancer is still there - it just too small to detect.

Within months it rears its ugly head again, and this time it is resistant to further treatment.

Key chemical

Dr Seckl's team concentrated their efforts on a growth factor known as FGF-2.

Growth factors work by latching on to tiny receptors on the outside of the cell and setting off a chain of signals that make the cell grow and divide.

Cancer patients have up to 20 times the normal level of FGF-2 in their blood.

The researchers found that FGF-2 combines with two other molecules to stimulate cell division, and with a third to counter the effect of anticancer drugs.

Dr Seckl said: "All four molecules are targets for new drugs that will block cancer growth and restore its sensitivity to existing treatments.

"Our aim now is to design and develop these new drugs."

Major problem

Professor Gordon McVie, Joint Director General of Cancer Research UK, said: "Resistance to treatment is a major problem we are yet to overcome.

"Dr Seckl's discoveries add vital pieces to the jigsaw of our understanding of this particularly nasty form of the disease.

"We now need to push on to find new drugs that will target these key molecules, stopping the cancer dead in its tracks."

Lung cancer, dubbed the 'invisible cancer' is the single biggest killer cancer in the UK.

Only 5% of the 40,000 people diagnosed in the UK each year survive the disease beyond five years.

Small cell lung cancers account for around a quarter of cases diagnosed.

The research is published in the Journal of Biological Chemistry.