Video-rate confocal reflection microscopy of neoplastic cells: rate of intracellular movement and peripheral motility characteristic of neoplastic cell line (RSK4) with high degree of growth independence in vitro.

Video-rate laser confocal interference reflection microscopy was used to demonstrate rapid motion of intracellular organelles and features at the cell periphery in a fully transformed neoplastic cell line, RSK4, and in four other neoplastic cell populations. In the RSK4 cells, vibrational and trafficking movements of intracellular particles at a rate greater than 25 Hz and ranging down to 5 Hz were recorded. Rapidly moving processes changed to ruffles, then microspikes, and previously undetectable ephemeral intercellular contacts were seen. Dynamic cyclical changes were revealed in the sizes of the podosomal close contacts of the transformed cells. The visibility of such features and the temporal and spatial resolution are improved over earlier methods. The fact that fast cellular and intracellular movements can be detected with this microscopic technique offers new possibilities in attempting to recognise differences between unimpaired living cells, and it may prove useful in the identification of malignant cells.