Proteomic and fractal analysis of a phenotypic transition in the growth of human breastcells in culture

Abstract

A novel approach to integrating quantitative description of cell aggregation dynamics andproteome analysis was used to identify early epigenetic transformations in cultured humanbreast cells. A transition from a power law to an exponential decay in MCF-7 cellaggregation was found and correlated with a down-regulation of calreticulin expression. Asimilar transition was not observed in the aggregation dynamics of MCF-10 nor inMDA-MB-231 cells, although they also exhibit changes in their global protein expressionpatterns during their prolonged culture. The down-regulation of calreticulin in MCF-7 cellsmay be associated with decreased cell–cell and cell–matrix adhesiveness and triggeringthe dynamic transition observed in their aggregation. The simple operationalmodel presented here may be a relevant tool for uncovering fundamental earlysteps involved in neoplastic transformation in culture and carcinogenesis in vivo.