Increased MPL expression and a correlation between MPL and Bcl-xL expression specifically in t(8;21) primary leukemic blasts. (A-B) Scatter plots showing microarray data extracted from a publicly available database comparing MPL transcript levels in t(8;21) and non-t(8,21) M2 AML samples using 3 probe sets (A) and comparing blasts with the indicated cytogenetic abnormalities.³⁴  (C) Leukemic blasts with t(8;21) or normal cytogenetics [non-t(8,21)] were lysed for RNA and quantitative PCR was performed for MPL. c-abl gene expression was used for normalization. (D) Immunoblotting was performed on equal number of peripheral blood mononuclear cells (cohort I) or BM mononuclear cells (cohort II) from leukemic patients for indicated proteins (*nonspecific band). x indicates and excluded sample. No AML1-ETO band is present in this t(8,21)⁺ sample, probably due to protein degradation. (E) Intensities of MPL and Bcl-xL blots were determined by densitometry and normalized to the medians from each cohort, followed by plotting normalized Bcl-xL value against MPL value for each sample. Trendlines and R-square (R²) values were generated for non-t(8,21) and t(8;21) groups using Apple Numbers Version 2009 software.