[Electrophoretic determination of aqueous and serum neuron-specific enolase (NSE) in the diagnosis of retinoblastoma].
OBJECTIVE
Neuron-specific enolase (NSE) or isoenzymes containing gamma-enolase are considered valuable in the diagnosis of tumors of neuroectodermal origin.


METHODS
We used rapid electrophoretic method on cellulose acetate plate to determine the patterns of enolase isoenzymes in the 21 aqueous humor and 23 serum specimens from 23 patients with retinoblastoma (Rb) and 21 aqueous and 25 serum specimens from 25 control cases to evaluate NSE in the diagnosis of RB. The assay allowed assessment of all three major isoenzymes (alpha alpha, alpha gamma, and gamma gamma), and NSE relative activity and its percentage in the total relative activity of the three enolase isoenzymes were assessed by means of a fluorometer.


RESULTS
Aqueous from all patients with Rb contained alpha alpha, alpha gamma, and gamma gamma isoenzymes and presented strong positive, the positive rate of NSE being 100% and its relative activity accounting for 45 +/- 9% of the total relative activity of the 3 enolase isoenzymes; no enolase was detectable in the control aqueous with cataract, glaucoma and Coats's diseases (4 cases), but in two patients with traumatic hyphema alpha alpha band, while the sera faint alpha gamma and gamma gamma presented in the aqueous. The control serum contained only an alpha alpha band, while the sera from patients with RB contained alpha alpha, alpha gamma and gamma gamma bands in 18 of 23 specimens, the positive rate being 78.2%, and only alpha alpha bands in the rest 5 specimens (21.8%). In the patients with Rb, the NSE relative activity and its percentage in the total relative activity of the 3 isoenzymes in serum (36 +/- 9%) were significantly lower than that in aqueous.


CONCLUSIONS
The amounts of NSE significantly in both serum and aqueous from patients with Rb, and the immunoelectrophoretic assay for determination of enolase patterns is valuable in the diagnosis and differential diagnosis of Rb. In addition, the method is rapid, simple and requires only a little among (< 5 microliters) of sample.
Wu
Z
Z
Zhongshan Ophthalmic Center, Sun Yat-sen University of Medical Sciences, Guangzhou.
Yang
H
H
Pan
S
S
D001082:Aqueous Humor / Q000201:enzymology*; D002675:Child, Preschool; D004588:Electrophoresis, Cellulose Acetate; D006801:Humans; D007223:Infant; D007527:Isoenzymes / Q000378:metabolism*; D010751:Phosphopyruvate Hydratase / Q000378:metabolism*; D019572:Retinal Neoplasms / Q000175:diagnosis*; D012175:Retinoblastoma / Q000175:diagnosis*
D007527:Isoenzymes; D010751:Phosphopyruvate Hydratase