Figure 6.

Human mammary fibroblasts (HMFs) are less responsive to DNA damage-dependent induction of activin A than are vHMECs. RM15 vHMEC and HMF, at the same passage, were treated with DNA-damaging agents (as described in Figure 5 legend). (A) Activin A and COX-2 mRNA levels were measured by using Q-PCR in triplicate and normalized to GUSB, used as an internal control, as described in the Methods section. (B) Activin A protein levels were measured with ELISA in duplicate 48 hours after treatment with the indicated agents. (C) Cartoon summarizing the expression changes after cell-intrinsic or cell-extrinsic DNA damage. Arrows indicate the induction of a gene or protein, whereas bars show repression of a gene or protein.