Two passionate researchers and their exciting projects

Dr Amanda Peacock and Dr Sam Siljee have carried out research with our team and made interesting findings.

Dr Amanda Peacock is a plastic surgical trainee at Middlemore Hospital. She put her training on hold last year to take part in a six-month fundamental research programme at the GMRI, investigating breast cancer. Dr Sam Siljee was one of our summer students in 2014–2015 and 2015–2016. He’s starting a PhD study on keloid disorder at the beginning of 2021.

Amanda investigated stem cells in breast cancer

Amanda often works on breast reconstruction and wanted to learn how to do quality research, as she feels there’s more scope for it in plastic surgery. She worked with Dr Swee Tan, who is also one of the consultant plastic surgeons at the regional plastic surgery unit at Hutt Hospital. Her project investigated the characteristics of the cancer stem cells in breast cancer and the involvement of the renin–angiotensin system (RAS).

What Amanda discovered

Amanda identified and characterised cancer stem cells in breast cancer using certain stem cell markers. She found that these cells express components of the RAS. Our team is preparing a manuscript on her discoveries for publication in a peer-reviewed scientific journal. She is also writing a review article on cancer stem cells in breast cancer to update surgeons on this field of research.

Amanda has found the experience very rewarding and encourages fellow trainees to take part in similar research.

Sam is investigating a novel low-cost treatment for keloid disorder

Keloid disorder is a condition that causes skin injuries to form excessive scars that behave like a benign tumour. These scars continue to grow and cause problems. The team at the GMRI has previously discovered stem cells that express the RAS and vitamin D receptor in keloid disorder. Sam’s PhD research will build on this work.

Findings from the project will also lead to a better understanding of Dupuytren’s disease and other unsolved fibroproliferative diseases affecting organs such as the lungs, kidneys, and liver.

The effects of keloid disorder

Keloids can have a big impact on people’s lives — as well as being disfiguring, they can cause joint contracture, pain, and itching. Keloid disorder affects all racial groups, but is more common in people with darker skin. It affects 2% of Caucasians and a larger, but unknown, proportion of Māori and Pasifika. 

This project aims to develop treatment for keloid disorder with existing low-cost medications

We don’t fully understand what causes keloid disorder, so current treatments are ineffective with very high recurrence rates following surgery. Sam’s project will investigate how exactly the RAS and vitamin D influence the stem cells of keloid disorder, and determine if we can treat it with existing low-cost medications, such as vitamin D and anti-hypertensive drugs. If proven successful, the project will benefit everyone with keloid disorder.

These low-cost medications are widely used for other purposes and their safety profile is well known.

We’ll investigate keloid disorder through an ‘ex-vivo’ model

Part of the project will involve developing a model system that replicates the features of keloid lesions so we can identify their vulnerabilities and test new treatments. This model will be an ex-vivo organ culture, meaning it will offer results that are as close as possible to experimenting on real keloid lesions.