Molecular mechanism and machinery driving unconventional secretion of Fibroblast Growth Factor 2 from tumor cells

The vast majority of secretory proteins contain N-terminal signal peptides for ER/Golgi-dependent transport into the extracellular space. Exceptions from this general mode of protein secretion from mammalian cells have been discovered more than 30 years ago, yet the molecular mechanisms underlying these alternative secretory pathways have remained elusive until recently. Proteins following such secretory routes have fundamental physiological functions in both health and disease, with Interleukin 1β and Fibroblast Growth Factor 2 being prime examples. The discoveries revealing the molecular mechanisms driving unconventional protein secretion did not only solve long-standing problems in molecular cell biology but also paved the way for new strategies for the treatment of for example inflammatory diseases and cancer.