Killer cells a natural in fighting melanoma
A study overseen by a Monash Biomedicine Discovery Institute (BDI) scientist has produced evidence for the first time that links the abundance of natural killer (NK) cells in melanoma with survival outcome.
Professor Nicholas Huntington said the study, published in Cancer Immunology Research, used a specially developed bioinformatics approach to demonstrate that NK cells played a role in the regulation of human tumours.
Natural killer cells, a subtype of lymphocyte (white blood cell), can spontaneously detect and kill cancer cells and can drive inflammation in tumours.
The researchers used the computational method to look at genomic data from tumours from hundreds of melanoma patients. This produced a score indicating the specific number of NK cells in a specific number of genes in a tumour.
“We found significant benefits in terms of overall and regression-free survival in patients who have a high amount of NK cells as opposed to patients with a low amount,” Professor Huntington said.
The results were significant for advancing understanding of what NK cells are doing in human cancer and also as a prognostic biomarker to indicate whether patients will respond better to certain immunotherapies, according to Professor Huntington.
“No one has looked in detail at the load of natural killer cells in each tumour and how that impacts survival,” he said.
“It can inform doctors based on the prognostic value of the score whether immunotherapy can be applied or not and maybe the type of patient care based on the likely outcome.”
“Traditionally most of the immunotherapy drugs are designed to target T lymphocytes or T cells. Our data suggest that targeting natural killer cells could also be a viable therapy option and that much more work is needed to be dedicated to studying the biology of these cells.”
Australia has one of the highest rates of melanoma in the world. It is the third most common cancer in Australian women and men. Melanoma, while aggressive, is relatively responsive to immunotherapy.
The researchers are working to develop therapies for worst-case scenarios of advanced metastasised melanoma.
“We need to bring more immune cells into the tumour so more patients respond to the immunotherapy,” Professor Huntington said.
He said the scientists were applying the data sets not only to melanoma but also to lung, prostate and breast cancers.
“We’re getting similar findings that natural killer cells affect most of these metastatic tumours.”
Professor Huntington, a long-term researcher in the field, was co-senior author on the paper with Dr Melissa Davis from the Walter and Eliza Hall Institute of Medical Research. First author was Dr Joseph Cursons.
This research was supported by the Melanoma Research Alliance, the NHMRC, Tour de Cure and the Harry J Lloyd Charitable Trust, among other funding bodies.
Read the full paper in Cancer Immunology Research titled A gene signature predicting natural killer cell infiltration and improved survival in melanoma patients.
About the Monash Biomedicine Discovery Institute
Committed to making the discoveries that will relieve the future burden of disease, the newly established Monash Biomedicine Discovery Institute at Monash University brings together more than 120 internationally-renowned research teams. Our researchers are supported by world-class technology and infrastructure, and partner with industry, clinicians and researchers internationally to enhance lives through discovery.