Figure 6. Reelin promotes MM cell growth via STAT3 pathway.

(A) The knockdown of STAT3 by specific siRNAs. H929 cells were co-transfected with pCrl and STAT3-specific siRNAs (or control siRNA, siNC) or pcDNA3 with siRNAs. Forty hours later, the cells were harvested and cell lysates were subjected to western blotting with Reelin and STAT3-specific antibodies. An antibody specific for GAPDH was used as loading control. (B,C) STAT3 contributes to Reelin-induced myeloma cell proliferation. The Reelin and STAT3 siRNAs co-transfected cells were cultured in FN-coated plates. Twenty-four hours later, a fraction of cells were subjected to western blotting with phospho-FAK (Tyr397), FAK, phospho-Syk (Tyr525/526), Syk, phospho-Akt (Ser473), Akt, phospho-4E-BP1 (Ser65), 4E-BP1 and Cyclin D1-specific antibodies. An antibody specific for β-actin was used as the loading control (B). The rest of the cells were analyzed for cell proliferation by BrdU staining (C). Similar experiments were performed for 3 times, and the representative results were shown.