Differences in growth and transcriptomic profile of bovine mammary epithelial monolayer and three-dimensional cell cultures.

Mammary epithelial cells (MECs) are characterized by specific spatial architecture with several distinguishing features such as: polarized morphology, specialized cell-cell contacts, and attachment to an underlying basement membrane. Three dimensional (3D) basement membrane cultures provide a unique opportunity to model the architecture of epithelium in vitro. The aim of this study was to characterize the growth of bovine mammary epithelial cell line BME-UV1 in 3D culture on Matrigel and identification of differently expressed genes in bovine MECs forming polarized structures in comparison to conventional monolayer (2D) cell culture. We demonstrate that BME-UV1 cells grown on Matrigel form polarized acinar structures during 16 days of culture. A microarray study has proven that the difference in spatial architecture between MECs cultured in monolayer and 3D system is reflected by differences in transcriptomic profile. Microarray data analysis showed 40 differentially expressed genes with statistical significance (p<0.05) and characterized biological functions. Identified genes comprised of cytoskeletal proteins, extracellular matrix components, kinases such as: Rac serine/threonine kinase, SRPK, protooncogene tyrosine-protein kinase ABL1, uridine cytidine kinase and proteins with nucleic acid binding / transcription factor activity. Products of those genes are involved in processes which are known to participate in regulating mammary gland polarization and function.