Journal: Clinical Cancer Research

Article Title: PRAME-Induced Inhibition of Retinoic Acid Receptor Signaling-Mediated Differentiation—A Possible Target for ATRA Response in AML without t(15;17)

doi: 10.1158/1078-0432.ccr-11-2524

Figure Lengend Snippet: Figure 1. PRAME-associated gene expression pattern and functional annotation. A, Western blot analysis of PRAME expression in AML cell lines compared with mRNA expression levels as determined by microarray analysis. This exemplary figure shows a dilution series of the AML cell line KG1 with low-PRAME expression (pink bar) and the cell line K562 with high-PRAME expression (purple bar). B, comparison of microarray-based and qRT-PCR-based PRAME expression measurement of randomly selected cases (n ¼ 29) reveals a good correlation (P < 0.001, linear regression analysis; depicted gene expression values are log2-transformed mean-centered expression changes). C, for data visualization, the top 100 ClassComparison analysis-derived PRAME expression-associated genes (rows) and AML samples (columns) were hierarchically clustered (average linkage clustering; similarity metric, correlation, uncentered; selected gene names are depicted). Cases with low- and high-PRAME expression (indicated by green and red bars, respectively) grouped together as indicated (for annotated probe sets, gene symbols are provided). D, selected results of a functional annotation analysis of the PRAME expression- associated signature using DAVID (ES, tells the overall enrichment of an annotation cluster with considering each of its members; count, indicates number of genes contained in the respective gene ontology term). E, PRAME expression levels in cell lines defined as low- and high-PRAME expression cell lines, respectively (plotted are log2-transformed centered gene expression ratios).

Article Snippet: The human cell lines K562, THP-1, KG-1, and Kasumi-1 were obtained from the German Collection of Microorganisms and Cell Cultures (DSMZ).

Techniques: Gene Expression, Functional Assay, Western Blot, Expressing, Microarray, Comparison, Quantitative RT-PCR, Transformation Assay, Derivative Assay

Journal: Clinical Cancer Research

Article Title: PRAME-Induced Inhibition of Retinoic Acid Receptor Signaling-Mediated Differentiation—A Possible Target for ATRA Response in AML without t(15;17)

doi: 10.1158/1078-0432.ccr-11-2524

Figure Lengend Snippet: Figure 3. siRNA-mediated PRAME knockdown in PRAME-high cell line: impact on ATRA-induced differentiation. A, transfection of PRAME-high leukemic cells (K562) with different siRNAs directed against PRAME. The most significant reduction in PRAME expression measured by RT-PCR was obtained with siRNA#8 following 24 and 72 hours after transfection (50% reduction, scrRNA). B, CD66b cell surface expression of leukemic cells treated with ATRA at a concentration of 107 mol/L following PRAME knockdown using siRNA#8. After 72 hours, cell differentiation as indicated by CD66b expression could only be mildly increased in PRAME-high K562 cells treated with scrRNA. However, PRAME knockdown significantly increased the ATRA-induced differentiation with results resembling findings in PRAME-low cells, thereby further suggesting a PRAME-blocked RAR differentiation. C, in accordance, cell growth as measured by cell counts was also more effectively inhibited by low-dose ATRA treatment in PRAME-high leukemia cells following siRNA-mediated PRAME knockdown.

Article Snippet: The human cell lines K562, THP-1, KG-1, and Kasumi-1 were obtained from the German Collection of Microorganisms and Cell Cultures (DSMZ).

Techniques: Knockdown, Transfection, Expressing, Reverse Transcription Polymerase Chain Reaction, Concentration Assay, Cell Differentiation

Journal: Clinical Cancer Research

Article Title: PRAME-Induced Inhibition of Retinoic Acid Receptor Signaling-Mediated Differentiation—A Possible Target for ATRA Response in AML without t(15;17)

doi: 10.1158/1078-0432.ccr-11-2524

Figure Lengend Snippet: Figure 4. Gene expression changes associated with siRNA-mediated PRAME knockdown and ATRA treatment. A, ClassComparison findings comparing siRNA knockdown and scrRNA K562 samples are depicted as volcano plot that combines the t test P value with the magnitude of the expression change following PRAME knockdown. On the y-axis the negative log10 of the P value and on the x-axis the log of the fold change following siRNA-mediated PRAME knock down (downregulated genes are plotted on the left). B, volcano plot depicting ClassComparison findings for ATRA-treated/untreated K562 samples.

Article Snippet: The human cell lines K562, THP-1, KG-1, and Kasumi-1 were obtained from the German Collection of Microorganisms and Cell Cultures (DSMZ).

Techniques: Gene Expression, Knockdown, Expressing