Quantification of mRNA levels by qRT-PCR demonstrated that shSTAT3 and shPI3K markedly reduced STAT3 and PI3K mRNA expression in U266 myeloma cells compared to control shRNA treatment (p < 0.01); shMAPK1 and shMAPK2 significantly reduced MAPK expression in the cells in comparison with control shRNA treatment (p < 0.05) (Figure 2A). This evidence concerns the gene STAT3 and plasma cell myeloma.