Figure 4

Elafin is expressed in non-tumorigenic mammary epithelial cells but not breast cancer cells. A) Lysates were collected from a panel of non-tumorigenic breast epithelial cells (mortal and immortal) and breast cancer cells (ER-positive and ER-negative) and subjected to Western blot analysis to detect elafin expression. B) Elafin levels were also assessed after treatment with PBS, Adenoviral luciferase (Luc), or elafin. Actin expression was assessed as a loading control. C) Breast cancer cell lines (MDA-MB-436, MDA-MB-157, MDA-MB-231 and MDA-MB-468) and non-tumorigenic breast epithelial cells (76NE6 and MCF-10A) were treated with PBS, luciferase (Luc) or elafin, cultured and counted for each day for four days.