DNA damage induced by UVA and UVB in squamous cell carcinoma progression

Funded Activity Summary

Australia has the highest incidence of skin cancer in the world. This results from immigration of individuals with fair skin to Australia. Skin cancer is three times as common as all other cancers combined. Overall, the incidence of skin cancer continues to rise in Australia and it will be several years before the true effectiveness of preventative programs are known. In the meantime, 1000 Australians die each year from skin cancer. Modern sunscreens, even those with high SPF and labelled as broad spectrum do not protect very well from UVA, though they are very effective UVB filters. Most sunscreens absorb or reflect only about 50% as much UVA as UVB. Thus sunscreen use alters the spectrum of UV received. This is an important issue, because if sunscreens are used to prolong sun exposure they will selectively increase the amount of UVA reaching the skin, and the sun contains a lot more UVA than UVB. There is only limited evidence to suggest they protect from skin cancer in humans whereas there is good evidence that they protect from precursor lesions. We have developed a new hypothesis, that UVB is primarily responsible for development of preneoplastic lesions (solar keratosis and dysplastic nevi) whereas UVA plays a relatively more important role in their progression to malignancy. This hypothesis would explain why sunscreens are more effective at preventing nevi and solar keratosis formation than they are at preventing melanoma and squamous cell carcinoma. Until the action spectrum defining the wavelengths responsible for skin cancer induction is known, the optimal methods for protection from skin cancer will be difficult if not impossible to design. That different wavelengths may be involved in different phases of skin cancer development in humans is a novel hypothesis: if it is correct it will have profound implications for both the design of sunscreens and our current public health programmes for skin cancer prevention.

Funded Activity Details

Start Date: 01-01-2002

End Date: 01-01-2002

Funding Scheme: NHMRC Project Grants

Funding Amount: $65,000.00

Funder: National Health and Medical Research Council

Research Topics

ANZSRC Field of Research (FoR)

Oncology And Carcinogenesis

ANZSRC Socio-Economic Objective (SEO)

There are no SEO codes available for this funding activity

Other Keywords

Genetic changes during skin cancer progression | Skin cancer progression | Solar Keratosis | Squamous cell carcinoma | Ultraviolet radiation | carcinogenesis | melanoma | photobiology | ultraviolet radiation exposure

Related Links