INPP5A and cerebellar degeneration: Furthermore, INPP5A inhibitors delivered selectively to UM tumors probably would be required because systemic delivery could have unacceptable side effects based on evidence that loss of the INPP5A gene is associated with development or progression of squamous cell carcinoma (60, 61), glioma (62, 63), and leukemia (61), as well as ataxia and cerebellar degeneration (21, 64).