[Morphology, cell-cell interactions, and migratory activity of IAR-2 epithelial cells transformed with the RAS oncogene: contribution of cell adhesion protein E-cadherin].

The destruction of stable cell-cell adhesion and the acquisition of the ability to migrate are consistent stages of neoplastic evolution of tumor cells of epithelial origin. We studied the morphologic and mi gration characteristics of epithelial cells of Iar1162 and IAR1170 clones derived from a mixed culture of on cogene N-RasV12-transformed cell line IAR-2. It was found that the mutant oncogene RAS can cause two types of morphological changes in IAR-2 epithelial cells.

[Sensitivity of the proliferation of normal and tumor cells to cytochalasin D].

The effect of cytochalasin D, which is known to disrupt specifically actin cytoskeleton, on DNA replication was studied. The incubation of cultured mouse embryonic fibroblasts (MEF), cells of Balb/3T3 line and cells of minimally transformed clones 12 MC and 6 st/T CAK-7 line with cytochalasin D leads to inhibition of DNA synthesis. A complete inhibition of labeled index in MEF culture was observed after an 8 day incubation in cytochalasin D.

[Effect of cytochalasin D on DNA synthesis in cultured cells].

The effect of cytochalasin D (CD), an agent specifically destroying actin cytoskeleton, on DNA replication of cultured mouse embryonic fibroblasts (MEF) and BALB/3T3 strain cells was studied. Incubation of normal cells with CD resulted in progressive inhibition of DNA synthesis: in the first 16-20 h the percentage of cells pulse-labelled with 3H-thymidine was similar to that in control cultures, on day 8 the percentage of labelled cells was 7-8 times lower than in the control. The transfer of cells into fresh medium upon 8-day incubation in the presence of CD resulted in the recovery of DNA synthesis.