Neural expression profile of Elav-like genes in human brain

Background: Hel-N1 and HuD belong to the elav gene family and have a consid erable role in neuronal development. However, there is only limited informa tion available on the expression profile in human brain and neural tumor ce ll lines.Method: Therefore, RT-PCR analysis has been performed on human fet al, normal adult, and psychiatric brains (from patients with schizophrenia, Alzheimer's disease, and alcoholism) as well as 20 glioblastoma and 9 medu lloblastoma cell lines.Results: Both, Hel-N1 and HuD were abundantly expres sed in all brain samples with no obvious difference. However, the neural tu mor cell lines showed a differential expression pattern. The medulloblastom a cell lines expressed at least one of the genes in a frequency of 67% for HuD and 78% for Hel-N1 transcripts, respectively. In contrast to the gliobl astoma cell lines, which revealed no evidence for HuD RT-PCR products. Surp risingly, 55% of the glioblastoma cell lines showed Hel-N1 expression.Concl usion: These observations indicate that Hel-N1 and HuD participate in molec ular processes in human brain, both during development and in the mature ad ult brain. Hel-N1 and HuD transcriptional activity are stable markers for m edulloblastoma cell lines, a tumor, which is thought to be derived from a n euronal precursor cell. The role of Hel-N1 in glioblastomas, the most promi nent representative of the glial tumors is presently unclear. This finding is the first indication for a possible involvement of an Elav-like gene pro duct in the glial cell lineage.