Figure 1.

Quantitative reverse transcription-polymerase chain reaction measurement of MPL, EPOR, ERBB2, and IGF1R mRNA in various tumor cell lines. Data were normalized to a set of housekeeping genes (GAPDH, cyclophilin, and β-actin). The normalized abundance of mRNA (y-axis) is scaled to 175,000 for all samples. Cycle threshold (Ct) values were calculated using the following equation: Abundance = 10e((40 − Ct)/3.35). Samples were scaled relative to each other using the geometric mean of the set of valid housekeeping gene datapoints for that sample.