CACNA1B and neoplasm: In short, it is possible that we are looking at a case of convergent evolution, that a βIII-like isotype may be required for neuronal growth and function and that a structure-function study of the particular residues conserved between vertebrate βIII and cephalopod tubulin isotypes could greatly increase our understanding of the role of the various tubulin isotypes in neuronal growth and function and could aid in the development of novel anti-tumor drugs.