EpoR siRNA knockdown showed no effect on tumor cell line viability. Effect of knockdown of gene expression using siRNAs was assessed by determining cell viability. The cell viability for each siRNA was divided by the median viability of cells transfected with approximately 10 000 irrelevant siRNAs to give normalized viability where 1.0 represents no effect. Each point is a normalized value for an siRNA. The rectangle shows the interquartile range (IQR) from the 25th percentile to the 75th percentile. The whiskers go from the minimum value to the maximum value unless the distance from the minimum value to the first quartile is more than 1.5 times the IQR. In that case, the whisker extends out to the smallest value within 1.5 times the IQR from the first quartile. A similar rule is used for values larger than 1.5 times the IQR from the third quartile. The vertical bar is the mean of the siRNAs targeting specific genes. In each graph, the top plot represents siRNA for PLK1, the second plot JAK2, the third plot EPOR, and the fourth and fifth plots in panels A and B CSFRA and CSFRB, respectively; the fourth plot in panels C-F and the sixth plot in panels A and B is the approximately 10 000 siRNAs targeting other genes. (A) UT-7/GM-CSF grown with rHuGM-CSF (Benjamin-Hochberg corrected P > .999 for EPOR). (B) UT-7/Epo cells grown with rHuEpo (P < .002). (C) A2780 cells grown without rHuEpo (P > .999). (D) A2780 cells grown with rHuEpo (P > .999). (E) NCI-H1299 cells grown without rHuEpo (P = .99). (F) NCI-H1299 cells grown with rHuEpo (P = .98).