Skin change offers key to cancer

Malignant melanoma is the most dangerous skin cancer

A simple molecular change can make normal skin cells behave just like cancer cells, shedding light on how tumours develop.

Scientists altered just one molecule which normally plays a role in how skin cells join up with other skin cells.

But this produced huge shifts in the behaviour, spread and appearance of the resulting cells.

Various treatments are available for skin cancers

"This component's loss appears to be an early critical event in the development of skin cancer," said Professor Elaine Fuchs, from the University of Chicago.

He said: "This molecule appears to be doing more than simply participating in cell-cell junctions."

Doctors believe subtle damage to cells, perhaps caused in some cases by overexposure to UV radiation from sunlight, may cause them to divide and grow out of control into a skin tumour.

But it is uncertain what sort of damage is likely to produce the malign growths.

Stick together

In this case, the scientists at Chicago bred mice missing the gene which produces alpha-catenin, a molecule with a role in causing cells to stick together and form part of the normal structure of the skin.

The mice suffered severe changes in the skin, which was thick and "disorganised" - the different cell layer types were distorted.

Cells often had more than one nucleus - a sure sign that there were not just defects in the way cells were joining together, but also problems in cell division.

Squamous carcinoma

The skin changes observed were very similar to those normally seen in squamous cell carcinoma, a pre-cancerous condition associated with overexposure to sunlight, and affecting thousands of Britons each year.

Looking closer into how alpha-catenin loss could have this effect, the team found that system which regulates cell growth had been activated.

Missing this molecule could lead to unregulated cell growth which characterises many forms of skin cancer.

If a key "missing link" to skin cancer development can be identified, it throws open a possible doorway to gene therapies which could help restore correct functioning to affected skin, or prevent cancers from developing in the first place.