[Effect of fibronectin on morphology and cytoskeleton of cultured epithelial liver cells].

Unlike nontumorigenic IAR2 cells, no surface fibronectin was detected in tumorigenic epithelial liver cells, IAR2-31 and IAR6-IRT7A. The adsorption of exogenous fibronectin purified from rat plasma, onto the substratum before seeding cells led to varying results in different cell lines. IAR2 showed no morphological changes or changes in the actin cytoskeleton, but acquired a network of radially oriented fibronectin fibrils. Under the effect of fibronectin single IAR2-31 cells returned to normal in terms of both the morphology and actin cytoskeleton, as well as acquired radially oriented fibronectin fibrils. At the same time IAR2-31 cells in the sheet were characterized by a circular actin bundle which made them essentially differ from IAR2 cells. IAR6-IRT7A cells were found to lose the ability to return to normal on fibronectin-coated substrates.