The correlation between BCL2 protein and mRNA expression level. (A) Correlation of BCL2 protein index with BCL2 mRNA measured by cDNA microarray in 30 cases of DLBCL. Protein index was generated based on the scores of staining intensity and the percentage of positive cells with immunohistochemistry. RNA was measured with the Lymphochip microarray.9 Each row represents measurements by a separate cDNA clone on the microarray. Gene expression is represented by the ratio between each experimental mRNA sample to the reference mRNA standard and is depicted according to the color scale shown at the bottom. Gray indicates missing or excluded data. (B) Scatter plot between BCL2 mRNA expression on cDNA microarray and BCL2 protein index measured by immunohistochemistry. BCL2 mRNA expression was calculated as detailed in “Study design” to more accurately reflect the true expression levels (*). The least squares fit line indicates good correlation (r = 0.81) of BCL2 protein level with BCL2 mRNA level.
