Figure 6

Exogenous elafin has growth-suppressive properties in luminal breast cancer cell lines normally lacking elafin expression. (A) Elafin mRNA expression (Log2 mean-centered values) derived from the Neve et al., 2006 publication of gene expression analysis in 48 breast cancer cell lines [23] and two HMECs. (B) qPCR analysis of elafin expression by indicated breast cancer cell lines, values normalized to GAPDH and represented as a ratio to elafin expression in 76NE6 cells. (C) The indicated cell lines were cultured in fresh media for 24 hours, conditioned media was subject to enzyme-linked immunosorbent assay (ELISA) analysis. A dilution series of recombinant elafin was used as a standard curve to determine the concentration of elafin in ng/mL of media. (D) MCF-7 and T47D cells were stably transduced with lentivirus containing wild-type elafin, elafin M25G or green fluorescent protein (GFP). Elafin expression was confirmed by western blot analysis of elafin expression. Actin, loading control. Each cell line was plated at 5,000 cells per well, cell number was measured at 48, 72, and 96 hours.