The invasiveness in vitro of brain tumour derived-cells depends on their micro-eco system.

In order to investigate the invasiveness of brain tumours, fragments of freshly resected tumours are transferred into cell culture vessels to form monolayers. The tumour derived monolayer cells are tested in two different in vitro assays for invasiveness: the collagen type I gel and the embryonic chick heart. Nine of the 10 tumour derived cells infiltrated into the collagen gel, independently of their clinical malignancy. Only 4 of the 10 tumour derived cells invaded the embryonic chick heart. Invasion into chick heart in vitro correlated with malignancy in vivo. The results speak for the hypothesis that the micro environment of the embryonic chick heart allows expression of the invasive character of the brain tumour cells, while the collagen type I in contrast indicates only cell motility.