Inhibition of intercellular communication: An in vitro assay for detecting potential tumour promoters.
The effects of non-cytotoxic concentrations of 13 chemicals on gap junctional intercellular communication (GJIC) in human keratinocytes and WB 344 cells were determined using a scrape-labelling method. The chemicals were selected according to their reported tumour-promoting effects in either the skin or liver, or their known skin irritancy potential. The in vitro assay was able to discriminate between genotoxic and non-genotoxic chemicals and, with keratinocyte cultures, ranked correctly a series of phorbol esters with regard to their reported tumour-promoting potencies in vivo. The data obtained support the suggestion that measurement of the inhibition of GJIC in vitro may provide a means to distinguish substances that have different tumour-promoting potencies.
Cooper
A
A
FRAME Alternatives Laboratory, Department of Human Morphology, University of Nottingham Medical School, Nottingham NG7 2UH, UK.
Fentem
J
J
Balls
M
M