Mef2c expression in MLL/ENL Mef2cΔ/−-transformed cells results in increased expression of several genes implicated in homing and invasive growth. (A) FACS analysis detected increase levels of CXCR4 expression on a subset of M/E cells of the indicated genotype immediately after recloning in methylcellulose cultures, which enriches for clonogenic or engrafting cells. Shown is one representative experiment of 3. (B-D) Microarray analysis was performed on RNA isolated from M/E Mef2cΔ/− cells infected with Mef2cASR/pac or pac vectors and subjected to puromycin selection. The relative expression levels (± SD) of the indicated gene for cultures expressing either Mef2cASR/pac () or pac (■) vectors are indicated. For some genes (marked with a Q), the results shown are that from quantitative RT-PCR, which in all cases confirmed the results obtained from the microarray. Results are shown for only genes that showed signals more than 4-fold above background. (B) Several chemokine receptors are up-regulated in Mef2c+ cultures. *Genes with mean signal intensities greater than 50-fold over background. (C) Several chemokines are highly expressed in MLL/ENL cultures and show up-regulation in Mef2c+ cultures. *Genes with mean signal intensities greater than 100-fold above background. (D) The expression of several MMP genes is up-regulated in Mef2c+ cultures. *Genes with mean signal intensities greater that 20-fold above background.