Influences of various substrata on morphology, motility and invasiveness of rat tumour cells. II. Studies on the highly metastatic variant BSp 73 ASML.

In a previous paper we studied the influences of the basal lamina and its components on the invasive but nonmetastatic variant BSp 73 AS of a rat pancreatic adenocarcinoma. In continuation of this publication we used the in vivo strongly metastasizing but hardly invasive variant BSp 73 ASML. On plastic or glass supports the low passaged ASML-cells grew separately, spread very scarcely and remained passive. Compared to these standard culture conditions, the behaviour of the tumour cells could be modified by biomaterials like collagen type I/III and type IV, fibronectin, laminin, matrigel, lens capsule and basal lamina. On these substrata (compared to plastic supports) the ASML-cells showed increased spreading, filopodial outgrowth and secretion of membrane vesicles. Only signs of motility as well as penetration of the biomatrices could be observed. Interestingly, highly passaged ASML-cells displayed an increased tendency to spread even on plastic. Under dynamic conditions these cells even failed to adhere. Obviously the biomatrices in vitro as well as long-term passaging are able to lead the ASML-cells partly to reactivate the behaviour that is characteristic of malignant tumour cells. Additionally, there is some evidence that the ASML-cells in vitro can strongly respond to chemotactic stimuli by exhibiting both flattening and translocative motility.