CONTENTS

Introduction
Human Skin Cancer
Sunscreen and Fabric
The Mouse Model of Cancer
Studies Using Skin Tissue
Drugs and Sunlight
Plant and Algae Growth
Conclusion
Glossary
Bibliography

Further Areas of Research

Another area of interest is artificial tanning. The problem with 'tanning' products on the market is that while they produce something like real pigmentation they only colour the skin and give no protection against UV light as a real tan does. A natural tan is caused by melanin that is produced in the epidermal skin layer. Dark skins are dark with melanin and are much less susceptible to skin cancer. The obvious question to ask with regard to fair Caucasian skin is how can we enhance its natural protective capability, how can we enhance this production of melanin without exposure to the UV which normally induces it.

Greenoak noticed an article in the popular press which related how a group in Arizona had succeeded in inducing melanin in mice. The substance they used induced pigmentation in the skin without UV. Just as importantly, this substance could be taken without applying it directly to the skin. Greenoak wrote to the scientists in Arizona in 1989 and offered the 'tanning' mouse as a suitable model for testing the new substance and its ability to protect mice from skin cancer. After a year of silence they responded enthusiastically and a collaborative group has been established which also includes workers at the University of Auckland in New Zealand.

“The possibility of enhancing natural protection is extremely attractive,” says Greenoak, “not least because it offers protection not only to humans but to the animal population at risk as well. Humans at least have sunscreens but domestic animals in the paddock or field, even if they have some shade available, remain at risk. A food additive or 'lick' which could enhance their protection would be quite a step forward.”

With only a small amount of money from the New Zealand Lotteries, Greenoak together with Dr Rebecca Mason of the Department of Physiology are undertaking the first pilot studies with this new substance and the tanning hairless mouse.