Programmed cell death protein 4 (PDCD4) is a well-known tumour suppressor and inhibitor of mRNA translation. Interestingly, the protein can play this inhibitory role only when localised in the cytoplasm, yet in most unstressed cells as well as cells derived from healthy tissues, PDCD4 resides almost exclusively within the nucleus. Its nuclear function remains unclear. Here we present a comprehensive investigation of all proteins and RNA interacting with the tumour suppressor in a non-tumorigenic epithelial cell line.