Fig. 6.

Relative CXCR4 mRNA expression of MDA-MB-231 cells transfected with PEI-GO:siCXCR4 complexes. PEI-GO was incubated with siCXCR4 at mass ratios of 0.3:1, 0.5:1, and 1:1 for 20 min at room temperature before cultured with MDA-MB-231 cells to achieve a final siCXCR4 concentration of 25 nM. Two days after siRNA transfection, cells were harvested for RNA extraction and real-time PCR analysis. Control, MDA-MB-231 cells cultured in growth medium for 48 h; Lipofectamine, MDA-MB-231 cells transfected with siCXCR4 using Lipofectamine 2000 as transfection reagent; PEI-GO:siMOCK, MDA-MB-231 cells transfected with PEI-GO:siMOCK at a mass ratio of 1:1. Error bars represent standard deviations (n ≥ 3). *p < 0.05 and **p < 0.01 compared to the control; ^## p < 0.01 compared to Lipofectamine