Interaction between human medulloblastomas and foetal rat brain aggregates in vitro.

The invasiveness of three medulloblastoma permanent cell lines (D-283, D-341, and DAOY), a human medulloblastoma biopsy, and in addition, a human rhabdomyosarcoma permanent cell line (TE-671), which previously had been regarded as a human medulloblastoma, was studied in an organ co-culture assay. All the four cell lines and the biopsy were co-cultured with normal rat brain cell aggregates for up to six days in vitro. The medulloblastoma biopsy, the D-283 and the D-341 cells invaded the brain tissue by diffuse single cell infiltration. The medulloblastoma cell line (DAOY) showed an invasive pattern similar to that observed earlier for most glioblastoma cell lines. This was characterized by massive cell replacement and destruction of normal brain tissue. The rhabdomyosarcoma cell line (TE-671) presented a solid invasive pattern with a fairly well defined border between normal brain and tumour tissue. Thus, the organ co-culture assay system in vitro seems to mimic several aspects of the in situ invasive behaviour of medulloblastomas. It may, therefore, provide new perspectives for pretreatment investigations with chemotherapy and radiotherapy of these malignancies.