Cancer cells use serotonin to boost the production of a molecule that is immuno-inhibitory, known as PD-L1. This molecule binds to killer T cells and renders them dysfunctional. The cancer cells thus avoid being destroyed by the immune system. The involvement of serotonin in carcinogenesis was already known, however the underlying mechanisms had remained obscure. The researchers therefore investigated the role of serotonin using syngeneic mouse models of pancreatic and colorectal cancer to show that genetic knockdown of peripheral serotonin enhanced CD8+ T cell accumulation in tumours and reduced tumour growth. Read more . . .
Scientists have discovered that approved antidepressant drugs cause immune cells to recognise and eliminate tumour cells in mouse models. New research from the University of Zurich, Switzerland, has found that drugs already approved as antidepressants inhibited tumour growth in mice with pancreatic and colon cancers. The findings could potentially lead to new cancer treatments that incorporate antidepressants in the future.