New insights found into aggressive mouth cancers

LONDON, Aug 1 (Reuters) Mouth cancer develops in two distinct ways which determine the seriousness of the disease, scientists said today, a finding that could lead to new ways of preventing and treating it.

In laboratory experiments using healthy, early and advanced cancer cells, the researchers discovered differences in the cells that determined the aggressiveness of the cancer.

''The data we collected provide strong evidence for the first time that some mouth cancer tumours are more aggressive than others and therefore linked to poor patient survival,'' said Professor Paul Harrison of the Beatson Institute for Cancer Research in Glasgow, Scotland.

Oral cancer often develops from pre-cancerous lesions, changes or patches in the mouth, that could be early signs of the disease.

Knowing which pre-cancerous changes are more likely to develop into aggressive tumours would enable doctors to determine the best treatment.

''Our work suggests it may be possible to identify in advance, by these molecular approaches, which of these pre-cancers are likely to progress and which need to be taken seriously at the outset,'' Harrison explained in an interview.

The scientists found that faults in the p53 gene, which stops damaged cells from dividing, and in the p16 gene, which helps to regulate and prevent cancer from developing, were two changes linked to more aggressive tumours.

The faults could form the basis of a diagnostic test for the illness, but Harrison said other so-called molecular signatures would be needed to make it a reliable test.

Smoking, other types of tobacco use such as chewing tobacco and heavy alcohol consumption are leading causes of mouth cancer.

Smoking and drinking are a particularly dangerous combination.

''Cigarette smoke contains carcinogens which cause mutations and changes in cells which generate the cancer formation,'' said Harrison, who reported his finding in the journal Cancer Research.

Like lung cancer, oral cancer usually develops in people in their 50s or older.

''The best thing to do with any cancer is to prevent it, if possible. In mouth cancer we know two of the major players. Smoking is a major factor but not everyone appreciates that heavy drinking is also a risk factor,'' Harrison added.

REUTERS MQA PM0928