Characterization of Transcriptome Diversity and In Vitro Behavior of Primary Human Breast Cells at Increased Risk for Breast Cancer Development

Studying properties of non-cancerous high-risk human breast epithelial cells is challenged by limitations in acquiring primary epithelial cells for investigation. Here we used conditional reprogramming cell (CRC) technology to isolate n=27 serial samples of non-cancer derived mammary epithelial cells ipsilateral to breast cancer, considered at risk cells for future breast cancer development. Comparative samples included cancer (n=8) and contralateral (n=3) and prophylactic mastectomy (n=1) non-cancer derived breast epithelial cells. Significant in vitro behavioral differences between samples were connected to baseline transcriptome characteristics. An exploratory analysis identified patterns of aberrantly expressed pregnancy development genes in both at risk and cancer samples. In conclusion, it is possible to approach the investigation of breast cancer risk utilizing human primary breast epithelial cells for targeted in vitro and genetic studies. Primary human breast epithelial cell mRNA profiles from breast epithelial cells isolated using CRC technology from non-cancerous breast tissue ipsilateral and contralateral to breast cancer and from a prophylactic mastectomy performed for breast cancer prevention, and cells isolated from breast cancer tissue.