Effect of ABCG2 overexpression on the expression of SLC transporter genes and MPP, glucose and glutamine transport.

Down-regulation of SLC transporter expression (SLC22A1, SLC22A3, SLC2A1, SLC38A2, SLC3A2, SLC7A5, and SLC7A6) in HEK293/R2 cells versus HEK293 was evaluated by PCR drug transporter array (A). Fold decrease expression was determined by the ΔΔCT method normalized to five housekeeping genes. Values given are the means (± SD) of three independent experiments (*P<0.05; **P<0.01). Initial velocity (5 min) of [3H]MPP (B), [3H]2-deoxy-D-glucose (C) and [3H]Glutamine (D) uptake was determined and values given are the means (± SD) of three independent determinations (*P<0.05; **P<0.01).