PATJ and neoplasm: Functional repurposing of tumor suppressor gene function is commonly seen in synaptic development and regulation, perhaps the best understood example of this is the (DLG) family of tumor suppressors (e.g., post-synaptic density-95), which mediate glutamatergic synaptogenesis via the postsynaptic clustering of AMPA receptors involving PDZ domain protein-protein interactions [30].