Alteration of midkine expression associated with chemically-induced differentiation in human neuroblastoma cells

Midkine (MK), a neurotrophic polypeptide of which expression is developmentally regulated in embryogenesis, is expressed in malignant tumor tissues including neuroblastoma (NB). A retinoic acid analogue, E5166, and dibutyryl cyclic AMP (dbcAMP) are known to induce differentiation in NB cells. This study showed that MK mRNA expression increased in association with differentiation by E5166, but not by dbcAMP in SK-N-SH and KP-N-RTBM1 human NB cell lines. We concluded that MK could be an important factor in differentiation of NB cells, and further, that there could be at least two pathways in differentiation of NB cells at molecular mechanism.