Research Paper Volume 12, Issue 14 pp 14285—14299

Figure 7. Involvement of p38 pathway in C5aR signaling-mediated the downregulation of p21 expression. (A–C) MCF-7 cells were pre-incubated with C5aRa (10 nM) for 60 min before exposure to recombinant murine C5a (480 ng/mL) for 30 min or 24 h. The cell lysates were assessed by western blotting using a polyclonal antibody against p-p38, p21 and the mRNA levels of p21 were measured by RT-PCR. (D, E) MCF-7 cells were pre-incubated with p38 inhibitor SB203580 (50 mM) for 60 min before exposure to recombinant murine C5a (480 ng/mL) for 24 h and then p21 expression levels were detected by western blotting with polyclonal antibody against p21 and the mRNA levels of p21 were measured by RT-PCR. *P < 0.05, **P < 0.01, ***P < 0.001. GAPDH was used as the loading control. All in vitro measurements were performed in independent quadruplicates with matching results.