IN-VITRO DIFFERENTIATION OF HUMAN NEUROBLASTOMA-CELLS INDUCED BY SODIUM PHENYLACETATE

Sodium phenylacetate (NaPA) at concentrations ranging from 2 to 6 MM s timulated morphological differentiation of two human neuroblastoma cel l lines IMR-32 and UKF-NB-3. These concentrations inhibited growth and DNA synthesis of the cells in a dose dependent manner without signifi cant effect on cell viability. The differentiated cells showed pseudog anglia formation and extension of cellular processes. The morphologica l differentiation in both cell lines was accompanied by decreased expr ession of N-myc oncoprotein. These results suggest that NaPA at concen trations, which have been achieved in humans with no significant adver se effects, promotes differentiation of cultured human neuroblastoma c ells in association with the reduced expression of the malignant pheno type.