Figure 4. STAT3 inhibition by siRNA persistently inhibits the IL-6/STAT3/NF-κB feedback loop and inactivates myofibroblast cells.

STAT3 was knocked-down in active breast stromal fibroblasts (CAF-346) with specific siRNA STAT3si (a scrambled sequence was used as control), and then the medium was changed and cells were cultured in siRNA-free medium till confluency and then were splitted several times. A. Cell lysates were prepared and used for immunoblotting analysis. B. Total RNA was prepared from the indicated cells, and then Let-7b and miR-21 levels were assessed by qRT-PCR. Error bars indicate mean +/− SD of three experiments. C. Cell proliferation, migration and invasion of the indicated cells were assessed using the RTCA-DP xCELLigence System.