Junctions between cancer cells in culture: ultrastructure and permeability.

Cell junctions between Novikoff hepatoma cells (N1S1-67) growing as small clumps or chains in suspension culture have been studied with ultrastructural, electrophysiological, and dye-injection techniques. Cells within clumps are commonly electrically coupled and can exchange dyes with a molecular weight of 332 to 500. Gap junctions and intermediate junctions are present, whereas true tight junctions and desmosomes are absent or very rare. This system should provide a useful model for studying the properties of "communicating" junctions.