High concentrations of enolase, alpha- and gamma-subunits, in the aqueous humor in cases of retinoblastoma.

Because retinoblastomas contain a large amount of the gamma-subunit of enolase or neuronspecific enolase, we studied the aqueous humor levels of the gamma-subunit and alpha-subunit in 12 cases of retinoblastoma. Enzyme immunoassay demonstrated that both the gamma-subunit and the alpha-subunit were greatly increased in all 12 (minimum levels, 87.8 ng/ml and 354 ng/ml, respectively). Thus, aqueous enolase levels, especially that of the gamma-subunit, are useful in the diagnosis of retinoblastoma and may be useful as monitoring markers in retinoblastoma involving the central nervous system.