TGF-beta-mediated microRNA expression in breast cancer cells

We utilized 3D-organotypic cultures whose physical properties were altered by inclusiong of type I collagen to create biomechanically rigid microenvironments that approximated those typically observed in primary mammary tumors. Compliant 3D-organotypic cultures were also generated to recapitulate the biomechanical properties of pulmonary microenvironments typically encountered by disseminated breast carcioma cells. The murine 4T1 progression series represents an established model of triple negative breast cancer development and metastasis and consists of isogenically-derived nonmetastatic 67NR, systemically invasive 4TO7, and highly metastatic 4T1 cells that were propagated for 6 days in the absense or presense of TGF-beta in either rigid or compliant 3D-cultures. Afterward, total RNA was extracted and subjected to miRNA profiling. two replicates of each growth and treatment condition for each cell line.