Sm. Bradykalnay et al., INCREASING N-CAM-MEDIATED CELL-CELL ADHESION DOES NOT REDUCE INVASIONOF RSV-TRANSFORMED WC5 RAT CEREBELLAR CELLS, Clinical & experimental metastasis, 11(4), 1993, pp. 313-324
The WC5 rat cerebellar cell line, infected with a Rous sarcoma virus (
RSV) that is temperature-sensitive for pp60v-src transformation, expre
sses high levels of the neural cell adhesion molecule, N-CAM, when gro
wn at the non-permissive temperature for pp60v-src activity. At the pe
rmissive temperature, N-CAM expression is 4- to 10-fold reduced and th
e cells aggregate poorly. To evaluate the effects of variations in N-C
AM expression, we compared the invasive ability of transformed WC5 cel
ls that express low levels of N-CAM with transformed cells in which N-
CAM-mediated adhesion was restored. WC5 cells were transfected with ex
pression vectors containing cDNAs encoding the 120 or 180 kDa forms of
chicken N-CAM linked to constitutive promoters. Several permanently t
ransfected lines that expressed chicken N-CAM at the cell surface were
isolated. These cell lines showed enhanced aggregation at the permiss
ive temperature relative to untransfected WC5 cells or cells transfect
ed with control constructs. By comparing the ability of control and tr
ansfected WC5 cells to invade reconstituted extracellular matrix, we t
ested the effect of variations in N-CAM-mediated adhesion on invasion.
Clones that expressed high levels of N-CAM showed invasion rates that
were similar to control cells, indicating that increasing N-CAM-media
ted adhesion does not inhibit the invasiveness of RSV-transformed WC5
cells.