The effect of cell density on E-cadherins expression, distribution and migration of hepatic cells and hepatoma cells / 生物医学工程学杂志

This research project was designed to explore the molecular basis of the loss of contact inhibition in hepatoma cells by regulating the cell growth density of hepatic cells (L02) and hepatoma cells (HepG2) respectively. Analyzing the character of morphology, the change of cytoskeleton, the ability of deformation, the expression and distribution of E-cadherins of hepatic cells and hepatoma cells with different density, we found: Hepatoma cells' E-cadherins increased when compared to the hepatic cells'; Hepatic cells' up-regulated E-cadherins, and with their increased growth density, hepatic cells gathered in the contacted areas; Hepatoma cells, however, tended to down-regulate the expression of E-cadherins, and they kept the fusion distribution. The migration rate and net migration distance of these two kinds of cells were inhibited by growth density. Hepatoma cells kept the strong ability of migration, but the migration trace discretization of hepatic cell decreased with the increase of growth density. Hepatoma cells kept the high discretization of migration trace in different growth density. These different results show that hepatic cells are in positive correlation with E-cadherins distribution, and are in negative correlation with its migration. There is no aggregation tendency seen with respect to hepatoma cells' E-cadherins. The effect of hepatoma cells' growth density on migration is not obvious.

Study on the overlapping growth of hepatoma cells in vitro / 生物医学工程学杂志

This study inquired into the formation of the "overlapping growth" of hepatoma cells through quantitative characterization on the growth of hepatoma cells in situ by means of morphological observation, Image Tool computer analytic system, statistical analysis as well as the experimental methods of cell mechanics and biochemistry. The results were as follows: (1) The ability of hepatoma cells to regulate cell morphological deformation was better than that of hepatic cells; (2) While we were using micropipette aspiration technique to suck the "overlapping growth plaque" of hepatoma cells, the "overlapping growth plaque" fell off from the substrate, leaving a blank area; (3) Integrin expression of hepatoma cells was more obvious than that of hepatic cells; (4) Fibronectin (Fn) down-regulated the integrin expression in the hepatoma cells cultured on the Fn coated surface, enhanced the cells' adhesion ability and morphological stability, but reduced the formation and aggregation of the round cells. These results indicated (1) The so-called overlapping growing area was actually formed by many closely arrayed and piled round cells; (2) The production of round cells may be caused by integrin abnormal expression and the effect on the hepatoma cells adhesion stability; (3) The formation of "overlapping growth plaque" in hepatoma cells is related to the round cells' congregation induced by the high frequency morphological transformation.