Immunohistochemical detection of olfactory-specific sensory transduction proteins in olfactory neuroblastoma.

Olfactory neuroblastoma (ONB) is a malignant tumor found in the superior nasal cavity. Although there is not adequate molecular evidence, ONB is considered to develop from olfactory sensory neurons (OSNs). Here, we immunohistochemically detected intense signals for the olfactory-specific sensory transduction proteins, G(αolf), adenylyl cyclase III, and cyclic-nucleotide-gated channel A2 in ONB, together with the conventional ONB marker, neuron-specific enolase, while the established OSN markers, olfactory marker protein and growth-associated protein 43, were not detected. These results indicate that ONB and OSNs share the same lineage and that the detected transduction proteins could serve as specific tumor markers for ONB.