HOXC6 and HOXC11 increase transcription of S100beta gene in BrdU-induced in vitro differentiation of GOTO neuroblastoma cells into Schwannian cells.

HOX genes encode transcription factors that play a key role in morphogenesis and cell differentiation during embryogenesis of animals. Human neuroblastoma cells are known to be chemically induced to differentiate into neuronal or Schwannian cells. In the present study, we investigated the roles of HOX genes in differentiation of GOTO neuroblastoma cells into Schwannian cells. When GOTO cells were grown in the presence of 5-bromo-2'-deoxyuridine (BrdU), they increased the expressions of two HOX genes (HOXC6 and HOXC11) and marker genes for Schwannian cells (S100beta and myelin basic protein). Forced expression of HOXC11 alone or both HOXC6 isoform 1 and HOXC11 induced the expression of S100beta in GOTO cells. In transient transfection experiments, the overexpression of HOXC6 and HOXC11 transactivated the S100beta promoter-reporter construct. Taken together, our results suggest that HOXC6 and HOXC11 are associated with differentiation of GOTO cells into Schwannian cells through the transcriptional activation of S100beta gene.