SU9516 decreased dihydrofolate reductase (DHFR) mRNA expression in Jurkat cells. (a) Jurkat cells were treated with the indicated concentrations of SU9516 or dimethyl sulfoxide (DMSO) for 24 h, and DHFR mRNA expression was evaluated using real‐time RT‐PCR as described. Total RNA (10 mg) was probed with DHFR cDNA. The quantity of DHFR mRNA obtained was normalized to the quantity of GAPDH mRNA (*P < 0.05, **P < 0.01). (b) Jurkat cells were treated with DMSO or 2 μM of SU9516 for the periods indicated, and DHFR mRNA was determined using real‐time RT‐PCR as described. Total RNA (10 μg) was probed with DHFR cDNA. The quantity of DHFR mRNA obtained was normalized to the quantity of GAPDH mRNA (*P < 0.05, **P < 0.01). GAPDH, glyceraldehyde 3‐phosphate dehydrogenase.