Immune cells from urine better reflect bladder cancer than cells from blood

 

Researchers have discovered that immune cells in the urine of patients with bladder cancer mirror immune cells in the tumour.

The discovery, by BRC-supported researchers at the UCL Cancer Institute and University College London Hospitals, could make it easier to track patient response to cancer treatment with a quick urine test as well as develop more effective immunotherapy treatments and prognostic tools.  

In the study, published in the Journal of Experimental Medicine, researchers showed for the first time that immune cells in the urine of bladder cancer patients accurately reflect those in the tumour environment and unexpectedly were more representative of the tumour than immune cells from the blood. 

The discovery could also help with the development of immunotherapy which has shown success in patients with advanced bladder cancer and is approved in the UK for certain patients. Despite this success, only around a quarter of patients respond to immune checkpoint-targeting drugs, and there is a pressing need to better understand the immune landscape of bladder cancer and develop new therapeutics. 

The study also identified a relationship between urine-derived T cells and patients’ chance of survival, as the disease was more likely to return in people with higher numbers of these cells. This indicates that urine-derived T cells may therefore also serve as a prognostic marker. 

The study, funded by Cancer Research UK, looked at 32 patients with bladder cancer that had invaded the muscle wall. Urine and blood samples were taken on the day of surgery to remove their tumour, and compared with both the tumour and healthy bladder tissue. 

The researchers were able to identify T cells in the urine, which are usually absent in healthy individuals. The T cells matched those found with the tumour environment regardless of cancer stage and treatment history.

Co-lead author, Dr Sophia Wong (UCL Cancer Institute), said: “Our results show for the first time that urine liquid biopsies can be used as a non-invasive window into the bladder tumour environment. 

"This valuable information could be used to discover immunotherapy targets and aid the design of combination treatments that exploit different components of the immune system.

“This research looked at a single time point, so clinical trials that include urine analysis over time are now needed to find out whether urine-derived T cells could tell us if a patient is responding to treatment, or be an early warning that a switch in therapy is required.”

There are around 10,300 people in the UK diagnosed with bladder cancer every year. And it can be difficult to treat; just more than half (53%) of patients survive their disease for 5 years or more. 

Dr Mark Linch, Consultant Oncologist at UCLH and Senior Lecturer at UCL Cancer Institute, who was also senior author on the paper said: “These results demonstrate what can be achieved when the clinical and scientific teams work closely together along with the tremendous support from the patients and their families.”

 

To read one personal story of taking part in the research go to the Guardian website.