Differentiation and morphogenesis of mammary cellsin vitro

Abstract

Cells of a mammary cell line [Rama 25] isolated from a DMBA[dimethylbenzanthracene]-induced rat mammary carcinoma undergo differentiation in vitro. A reversible differentiation leads to the formation of 2 types of microstructure (domes and ridges). The mechanism of dome formation was studied. This differentiation is initiated by inducers, some of which are generated in the cultures and act locally; their effect is strongly dependent on cell concentration and requires hydrocortisone. There are exogenous inducers as well as inhibitors. In the pathway to dome formation important roles are played by c[cyclic]AMP (probably intracellular and extracellular), the organization of the cytoskeleton and the Thy-1 antigen. The pathway and the significance of the phenomenon for mammary gland development are discussed.