GAP-JUNCTION PROTEIN GENE SUPPRESSES TUMORIGENICITY

Prompted by the notion that the membrane channels in gap junctions con duct growth-regulating signals from cell to cell, we transferred the a lpha1 gene for the channel protein (connexin43) of rat heart to tumori genic mouse MCA-10 cells. Upon incorporation into the cell genome, thi s exogenous gene was expressed, resulting in functional channels and n ormal growth regulation: cell-cell communication, determined with a ch annel-permeant 400-dalton fluorescent tracer, was increased and tumori genicity, determined in nude mice, was suppressed.