it was found that at their point of contact with the endothelial tube of the peri-tumour vein , the tumour cells caused the endothelial basement membrane to disappear and they entered the vein lumen either by inducing an opening of interendothelial junctions , or by causing intensive vacuolation and disintegration of individual endothelial cells -- and thus producing gaps for their passage into the lumen .
C1179027
endothelial
C0042449
vein