By Professor Sarah Newbury – Brighton and Sussex Medical School (BSMS)
Melanoma microRNA biomarker project
The overall aim of our study is to identify microRNA biomarkers from the circulating blood to detect recurrence in malignant melanoma. MicroRNAs (miRNAs) are small non-coding RNAs which are known to control cellular pathways through post-transcriptional control of gene expression.
These miRNAs are surprisingly stable in the circulating blood because they are encapsulated in lipid particles termed exosomes and/or are bound to protective proteins. A number of recent studies have identified miRNA biomarker signatures from circulating blood which can differentiate between melanoma patients and healthy controls.
However, relatively few studies have used staged samples to identify miRNA signatures that can distinguish localised melanoma (non-metastatic (Stage I/II)) from the more life-threatening invasive melanoma (metastatic (Stage III/IV)). The prognostic value of miRNAs as biomarkers for melanoma would be greatly enhanced by determining which patients, after surgical removal of a non-metastatic melanoma, are most likely to progress to metastatic cancer.
Identification of these patients would greatly enhance their likelihood of survival as there are now a number of drugs available that are effective against certain subtypes of melanoma. Our previous work, funded by the Melanoma Fund and carried out at the Blond McIndoe Research Foundation and the Brighton and Sussex Medical School, identified three potential miRNA biomarkers that can distinguish Stage I/II from Stage III/IV melanoma, plus three potential reference controls.
The melanoma microRNA biomarker project has now entered its next stage!
Funding from the Melanoma Fund has allowed us to take on a new technician, Sophie Mumford, who started work on 1st September, 2017. Sophie is being supervised by myself as grant-holder, together with two experienced members of my research team, Dr Ben Towler and Ms Amy Pashler, both of whom are experienced in the analysis of miRNA biomarkers.
Dr Yella Martin, who has been involved in the project from the start, has joined us for two meetings to discuss and plan Sophie’s experiments; one meeting took place before Sophie started to discuss training and experimental details, and the other more recently was to demonstrate that she could perform the techniques accurately and also plan a literature review for the Introduction to our future publication.
The first step of Sophie’s work has been to practice quantitative RT-PCR, a technique which can currently measure only a few molecules of the miRNA biomarkers extracted from serum. Subsequently, she has catalogued samples moved from the Blond McIndoe Research Foundation labs to the labs in the Medical Research Building.
Having successfully completed these tasks, she is now embarking on using these patient samples to check and validate the miRNA biomarkers we identified in our previous experiments. She also aims to check out possible “reference controls” to help in comparing the patient samples against each other. Since the project is taking place in the Medical School, I have had the opportunity to introduce the project to my medical student tutorial group. They seem very interested and I will encourage them to engage more with the project in the future.