Increased Shp2 expression in primary leukemia cells. (A) A representative Western blot result of partial leukemia cases. (B) Statistical analysis of all cases tested. For each sample, 20 μg cellular proteins was analyzed by Western blot for Shp2 and β-actin. Results were expressed as the ratios of Shp2 to β-actin, and the mean value in each group was indicated. (C) Total RNA was isolated from fresh leukemia cell samples from patients at diagnosis, and analyzed by RT-PCR using Shp2-specific primers described in the text. β-actin cDNA primers were used as internal control. PCR products were electrophoresed on 1% agarose gel stained with ethidium bromide. (D) Results were expressed as the ratios of Shp2 to β-actin. Horizontal lines in panels B and D represent means.