New research has shown that steroid creams can shrink melanoma tumours – the deadliest form of skin cancer.
Cancer researcher and dermatology registrar at Salford Royal Dr Charles Earnshaw was first author of the study exploring using cream-based treatments (currently used as part of treatment for non-melanoma skin cancers) in melanoma.
Dr Earnshaw is among the team at Dr Santiago Zelenay’s laboratory at the Cancer Research UK Manchester Institute who have been working to understand why immunotherapy currently only helps around half of patients with melanoma.
They found commonly available steroid creams – which they expected to suppress the immune system – in fact caused an uptick in immune activity and the killing of the melanoma cells.
They say steroids blocks a protein called GARP, which helps cancer hide from the immune system. By inhibiting GARP, the immune system was reactivated to target cancer cells.
Therapeutic target
This large body of work spanned the analysis of cancer cells in the lab, animal models of melanoma, human patient databases and patient samples from the Christie Hospital. It could help us better understand how to treat melanoma, whether that involves incorporating treatment with steroids, or designing new treatments that target GARP.
Dr Earnshaw said: “This study shows that there might be circumstances where steroids can trigger immune responses to cancer, and it suggests that this protein called GARP might be a really nice therapeutic target going forward to inhibit in melanoma, and potentially other cancers as well.
“We are planning further research to look at the potential for treating patients who do not respond to other treatments, including immunotherapy. Our pre-clinical data suggests that we also see responses in breast cancer and colorectal (bowel) cancer using the steroids so, with further research, expanding into other cancers is very viable.”
Faster process
He added: “It also highlights the potential of using an already-approved treatment. This not only saves us from having to start entirely from scratch, but also helps streamline key stages of the drug development process, potentially bringing new treatment options to patients more quickly.”
Group Leader at the Cancer Research UK Manchester Institute, Dr Santiago Zelenay said: “This research is particularly exciting because it shows that, in certain cases, steroids – one of the most commonly administered drugs to cancer patients and usually thought to weaken the immune system may actually help the body fight back. The study suggests that these medicines could sometimes slow down tumour growth by boosting a patient’s own immune response.”
The paper, Glucocorticoids unleash immune-dependent melanoma control through inhibition of the GARP/TGF-β axis, has been published in the journal Cancer Discovery.
This research was funded by Cancer Research UK, Wellcome, Ian Nelson, and the National Institutes of Health, with additional support from the NIHR Manchester Biomedical Research Centre.