Research Paper Volume 8, Issue 8 pp 1650—1669

Figure 7. Signaling pathways implicated in SDC1 expression by senescent human breast stromal fibroblasts. (A) Ionizing radiation-mediated senescent human breast fibroblasts (IS) were treated with the p38 MAPK inhibitor SB203580 or the NF-κB inhibitor BAY117082 (10 μM) and 24 h later SDC1 expression was assessed by real-time PCR. (B) p53 expression was silenced in IS cells by siRNA, as indicated in the Materials and Methods and SDC1 expression was estimated as in A. One representative experiment out of three similar ones is depicted in each case (* indicates p < 0.05 in comparison to the untreated control). In the left panel, the efficiency of SB203580 and p53 siRNA in down-regulating the downstream molecules p16^INK4a and p21^WAF1, respectively, as assessed by western analysis, is depicted.