Drugs for a common eye condition could one day be used to treat certain aggressive cancers, including breast cancer, melanoma and a type of blood cancer.
Scientists at The Institute for Cancer Research found these cancers rely on the same molecule to become aggressive and spread
Their study found existing drugs which block the molecule and are currently used to treat patients with glaucoma could be repurposed to help fight cancer. It also identified certain markers which could determine which patients may respond well to the drugs.
Experts said that the study “lays the foundations” for identifying suitable patients, and repurposing drugs which have already proven to be safe could mean they reach patients faster.
Lead author Victoria Sanz Moreno, professor of cancer cell and metastasis biology, said: “Some cancers are particularly aggressive, and once they spread they become very hard to treat.
“Catching these aggressive cancers and preventing their ability to move around the body is really crucial to our mission to keep more people living well with cancer.
“Our research has identified a shared weakness of aggressive cancer cells that could be targeted across many cancer types, wherever they originate in the body.
“We confirmed our findings in aggressive cancers such as breast cancer, melanoma, and a type of blood cancer called acute myeloid leukaemia, but we believe this molecular fingerprint of cancer cells likely to die after treatment applies to many more cancer types.
“It’s reassuring to know that a treatment already exists – a drug currently being used safely in some patients could be adapted to treat these cancers.”
Researchers set out to find markers that could be used to identify which cancers would respond well to drugs that block a molecule called ROCK, also known as Rho kinase.
When cancer cells spread around the body, they cause advanced disease that is hard to treat, and these aggressive cells rely on ROCK.
The molecule keeps the scaffolding of cells tense, making the cells contract and become round, which generates force for the cancer cells to squeeze through tissue.
The study, published in the journal iScience, saw researchers look for markers that could be used to identify which cancers would respond well to drugs that block ROCK – which are already in use to treat glaucoma.
The team, working in the Breast Cancer Now Toby Robins Research Centre at the ICR, looked at information from a drug sensitivity database to identify which types of cancer cells responded to ROCK inhibitors.
Researchers found that breast cancer cells that responded to ROCK inhibitors had a particular gene that was not working properly, called E-Cadherin.
In melanoma, the database showed that cells that respond to ROCK inhibitors tended to have a more rounded shape and high activity of a signalling pathway called NFKB.
And acute myeloid leukaemia cells that responded well to ROCK had a specific subset of gene alterations.
The findings were then turned into lab experiments on tumour samples and studies in mice.
The researchers hope that in the future a biopsy of a patient’s cancer showing these markers could indicate whether ROCK inhibitors would work well for the patient.
Dr Simon Vincent, chief scientific officer at Breast Cancer Now, said: “With around 11,500 women tragically dying from breast cancer every year in the UK, research like this is vital to finding more effective treatment options.
“This study helps to lay the foundation for understanding who among those with certain cancers, including breast cancer, might benefit most from existing drugs. Finding new uses for existing treatments, which we know people can safely take, is easier and faster than developing new cancer drugs from scratch.
“It’s encouraging that these drugs may be especially effective in targeting cancer cells that are more likely to spread and resist treatment.
“While this research is still at an early stage and clinical trials are needed, it’s an important step towards more personalised breast cancer treatments in the future.”
First author of the study, Jaume Barcelo, postdoctoral research fellow at The Institute of Cancer Research, London, now based at the Barts Cancer Institute at Queen Mary University of London, added: “Our study has identified a specific pattern of features that is consistent across many cancer types, and that can be used to match the right patients to this treatment.
“The next stage for this research will be to test how these drugs that inhibit ROCK work in combination with other treatments, to maximise the benefit for patients.
“As ROCK inhibitors are already approved to treat glaucoma, I hope that our findings can be used to progress the drugs into clinical trials to treat cancer in the near future.”
Susanna Daniels, chief executive officer of the charity Melanoma Focus, said: “Despite major advances in melanoma treatment over the past decade, too many people still die from the disease each year, and not every patient responds to the treatments currently available.
“Every new discovery improves our understanding of how melanoma grows and survives, bringing us closer to treatments that are more effective, more targeted and have the potential to improve survival.
“While these findings are still at an early stage and will need to be tested in clinical trials, they offer an encouraging direction for future melanoma research and the development of more personalised treatments.”