DBN1 and urinary bladder cancer: However, because drebrin A is considered the neuron-specific isoform, while drebrin E expression is more ubiquitous [36], we can reasonably assume that bladder cancer cell lines likely express drebrin E. We have transiently expressed both drebrin isoforms in 5637 cells and we could not detect any differences in their ability to regulate progranulin-dependent F-actin remodeling.