[Inhibitors for protein tyrosine kinases, erbstatin, genistein and herbimycin A, induce differentiation of human neural tumor cell lines].

Recent reports suggest that protein phosphorylation is involved in neural differentiation. We have found that specific inhibitors of protein phosphorylation at tyrosine residues, Erbstatin, Genistein, Herbimycin A, effectively induce neural differentiation in a human neuroblastoma cell line SK-N-DZ and a human medulloblastoma cell line Med-3, as indicated by the marked increase in the number of neurites/cell and in the expression of neurofilaments (160 k) detected by immunohistochemical studies. Possible involvement of protein phosphorylation at tyrosine residues in the differentiation of neural tumor cells was stressed.