Did you know that sea turtles can get cancer? Sometimes tumours become so large that they inhibit the turtles swimming, feeding or vision. At the Sea Turtle Hospital, David is using genetics to learn which human anti-cancer drugs can be used to treat turtles.
My father’s family are seafarers. Their lives revolve around the fishing industry and serving in the Royal National Lifeboat Institution. So when I was growing up in Dublin, Ireland, much of my childhood was spent along the coast or out on boats, and throughout my life my affinity for the ocean has endured. During my undergraduate studies in zoology I studied the marine ecosystems and wildlife around the Irish coast and took part in an island biogeography project in Indonesia, where I was first captivated by wild sea turtles.
My postgraduate studies took me to the west of Ireland to study...
This project aims to harnesses proven human cancer research approaches to identify drugs to treat sea turtles with FP tumours. This project will underpin a larger study to support the conservation of sea turtles by treating individuals with FP, and elucidating the relationship between the herpesvirus, habitat-degradation and tumour development.
Four sea turtle species are endangered or critically endangered, two are vulnerable, and one is data deficient (IUCN Red List). Fibropapilloma has been recorded in all seven species. The spread of FP represents a critical oncological threat, which undermines conservation efforts and requires an urgent response. Surgically treating and rehabilitating all turtles with FP is not feasible, and generally only stranded turtles enter rehabilitation hospitals. As FP triggers are environmental it is likely that, once released, rehabilitated turtles will again develop tumours. Therefore, it is vital that rapid, inexpensive treatments for FP are developed that can contribute effectively to turtle conservation. Pharmacological intervention has the potential to be more widely applicable than surgery, even in widely dispersed populations, and the mainly external nature of FP means drugs can be easily delivered directly into the tumours. Generating high-throughput genetic tumour and viral sequence data will help resolve the etiology of FP.
Green sea turtles (Chelonia mydas) are the species most affected by FP, but it also occurs in all other sea turtle species and its geographic range is spreading. Currently, surgery is the primary treatment for turtles with FP, but almost 40% of turtles that have tumours surgically removed experienced regrowth. The regrowth occurs within an average of 36 days, but since records were only for the relatively short period of captivity it is likely that the true occurrence of regrowth is much higher. Therefore, novel therapies are urgently needed to enhance the outcome of turtles with FP. Human oncology has proven that adjunct pharmaceutical therapy can improve patient outcomes post-surgery. Indeed, in a number of cases anti-cancer drugs alone (without surgery) are sufficient to cure patients. This is especially true for more benign non-metastatic cancers. FP in turtles in many respects resembles non-metastatic cancer; although numerous lesions occur in each individual these are thought to be de novo primary tumours, no metastatically-spread secondary tumours. In addition, tumours primarily occur on the bodies extremities, and in the rare cases where tumours are found on internal organs (~25% of turtles with FP) they are again thought to be primary tumours and not the result of metastatic disease. The benign nature of FP, with the physical effects of the tumours leading to mortality, rather than aggressive tumours themselves, suggests that it would respond well to drug therapeutic treatments. Therefore, the aim of this study is to determine the most effective drug treatment for turtles with FP. To achieve this we will employ the most recent and effective approaches in human cancer therapeutic research: genomic- and network-based precision medicine. We have previously successfully implemented these approaches in the human setting.
How do we learn about marine food chains when the animals are so difficult to observe? Stable isotope analysis (SIA) shows us what animals eat. Diana will use a new method that combines SIA and amino acids and analyze tissue samples of captive sharks and rays to get a more accurate picture of how this method can be used with wild populations.
Since the 1970’s scientists have been using satellite tags to track wildlife, but with GSM technology- the same system that cell phones use- there may be a better, more accurate and more cost effective solution especially for elusive marine animals. Guilia is working on it.
Bimini in the Bahamas is home to large populations of sharks. Mariana will observe whether the presence of those sharks affects how turtles use their habitat and whether more turtles means more sharks. Bimini is undergoing intensive development for tourism, so understanding how animals use their space is critical for their conservation.