Susceptibility Of The Basal Layer Of Human Epidermis To UVA Oxidative Damage Due To Pheomelanin And Suboptimal DNA Repair
Funder
National Health and Medical Research Council
Funding Amount
$559,354.00
Summary
Australia has the highest incidence of skin cancer in the world. It is important to understand how sunlight causes skin cancer and the wavelengths involved in order to devise effective preventative and therapeutic strategies. Our proposal is that the cells in the skin that give rise to the most common forms of skin cancer, squamous cell carcinoma and basal cell carcinoma, are particularly vulnerable to UVA. We aim to study why this is the case and whether this vulnerability can be prevented.
Determination Of An Action Spectrum For Ultraviolet Radiation-induced Immunosuppression In Humans
Funder
National Health and Medical Research Council
Funding Amount
$213,500.00
Summary
Ultraviolet (UV) radiation causes mutations in the skin which can develop into cancers many years later. The skin's immune system is an important defence that prevents most potentially cancerous cells from developing into skin tumours. UV also suppresses skin immunity, allowing cancer cells to proliferate unchecked. There is also evidence that this UV-induced immunosuppression may have important effects on infectious diseases such as herpes virus, leprosy and tropical ulcers. Sunlight contains U ....Ultraviolet (UV) radiation causes mutations in the skin which can develop into cancers many years later. The skin's immune system is an important defence that prevents most potentially cancerous cells from developing into skin tumours. UV also suppresses skin immunity, allowing cancer cells to proliferate unchecked. There is also evidence that this UV-induced immunosuppression may have important effects on infectious diseases such as herpes virus, leprosy and tropical ulcers. Sunlight contains UVB, which causes sunburn, and UVA. Until recently, UVA was thought to have little effect on skin immunity. We have previously shown that both broadband UVB and UVA are immunosuppressive, even after single exposures equivalent to 8 minutes of sunlight. It is not known which UVA wavelengths are most immunosuppressive. These studies will use a xenon arc solar simulator and a series of interference filters to produce narrow UVB and UVA wavebands. The effects of these wavebands on humans can be studied by deliberately eliciting immune responses to substances which volunteers are already sensitive to. One model of skin immunity in these studies is allergy to nickel (in earrings and costume jewellery), which affects 10% of women. The volunteers' backs are exposed to different UV wavelengths, and then nickel patches are taped to both the UV-exposed areas and adjacent, unexposed areas. By comparing the intensity (redness and thickness) of these nickel reactions, immunosuppression caused by each waveband can be measured. Similarly, the Mantoux reaction (in people vaccinated against tuberculosis) provides another, complementary model of skin immunity. Knowledge of the immune effects of different UV wavelengths (an action spectrum for UV immunosuppression) would improve understanding of skin cancer and enable development of better sunscreens, which currently offer only partial immune protection.Read moreRead less
Quantitiative Assessment Of Solar UV Exposure For Vitamin D Synthesis In Australian Adults
Funder
National Health and Medical Research Council
Funding Amount
$1,162,536.00
Summary
This research program will add significantly to our current scientific understanding of the dual health outcomes of UV exposure (Vitamin D and skin cancer) . This project is in line with Australia's R and D Priorities, in that it will result in direct and indirect social and economic benefits to Australia by applying the scientific knowledge gained through this research to develop public health initiatives to improve some of Australia's most significant and costly health problems.
Interaction Of Mc1r With The PRb And P53 Pathways In UVR-induced Melanoma Development
Funder
National Health and Medical Research Council
Funding Amount
$553,479.00
Summary
This project will shed light onto fundamental processes causing UV-induced melanoma (MM). Innate differences between individuals, independent of pigmentation, influence MM development. We will study the mechanisms of UVR-induced MM development in mice carrying gene mutations (Cdk4, Arf, Mc1r) that underpin human MM susceptibility. Knowledge of the sensitivity of an one's MCs to UV could be critical for targeting susceptible groups for health education campaigns and more intense screening.
The discoveries made to date and the proposed studies point to an intrinsic role for vitamin D compounds in skin in providing protection from sun damage. As a result of sun exposure, increased concentrations of vitamin D compounds in skin will be generated and this is likely to provide protection against further UV damage, in much the same way as increased pigmentation and increased thickness of the outer layer of skin. Furthermore, the studies are designed to test whether vitamin D compounds wh ....The discoveries made to date and the proposed studies point to an intrinsic role for vitamin D compounds in skin in providing protection from sun damage. As a result of sun exposure, increased concentrations of vitamin D compounds in skin will be generated and this is likely to provide protection against further UV damage, in much the same way as increased pigmentation and increased thickness of the outer layer of skin. Furthermore, the studies are designed to test whether vitamin D compounds which have minimal effects on serum calcium, could nevertheless be used topically in association with a sunscreen or moisturizer to add to sun protection. As Australia has the highest skin cancer rates in the world, this would be of significant health and economic value.Read moreRead less
Sun Exposure, Vitamin D And The Outcome Of Prostate Cancer.
Funder
National Health and Medical Research Council
Funding Amount
$494,698.00
Summary
We will find out whether hours of sun exposure, reported in a standard interview by men with prostate cancer, reduces prostate cancer recurrence and progression. For any effect of sun exposure ithat we observe, we will find out whether it works through vitamin D, which is produced by sunshine on the skin, or is affected by changes in the vitamin D receptor gene, which produces the protein the binds with vitamin D on cells and makes it work. Prostate cancer is the most common cancer in men in Aus ....We will find out whether hours of sun exposure, reported in a standard interview by men with prostate cancer, reduces prostate cancer recurrence and progression. For any effect of sun exposure ithat we observe, we will find out whether it works through vitamin D, which is produced by sunshine on the skin, or is affected by changes in the vitamin D receptor gene, which produces the protein the binds with vitamin D on cells and makes it work. Prostate cancer is the most common cancer in men in Australia, and this study, using two of the largest collections of clinical outcomes data for this disease, will inform researchers, clinicians and consumers about the possible benefits of sun exposure and Vitamin D in the prevention of recurrence or progression of prostate cancer. On present evidence, these effects are very plausible possibilities. It may also identify sub-groups of men in whom sun exposure or vitamin D might be particularly beneficial in improving outcome of prostate cancer.Read moreRead less