The tumor microenvironment plays a critical role in breast cancer growth and progression to metastasis. Here, we describe a method to examine stromal-epithelial interactions during tumor formation and progression utilizing human-derived mammary epithelial cells and breast stromal cells. This method outlines the isolation of each cell type from reduction mammoplasty tissue, the culture and genetic modification of both epithelial and stromal cells using lentiviral technology, and the method of humanizing and implantation of transformed epithelial cells into the cleared mammary fat pads of immunocompromised mice. This model system may be a useful tool to dissect signaling interactions that contribute to invasive tumor behavior and therapeutic resistance.
Keywords: Breast cancer; Human mammary epithelial cells; Human-in-Mouse model; Mammary gland; Stroma; Stromal–epithelial interactions.