While immunotherapy has revolutionised cancer care by helping the body’s immune system fight the disease, it doesn’t work for everyone. One of the biggest hurdles? The ‘wall’ tumours build around themselves. “Immune cells need to be able to enter a tumour to kill cancer cells, but cancers can actively block this process,” Dr Chiu said. Her research explores a new frontier: the idea that tumours release specific enzymes to stop immune cells from reaching them.