ABSTRACT
<p><b>OBJECTIVE</b>To investigate the effect of 5-fluorouracil (5-FU) on the expression of ATP-binding cassette superfamily G member 2 (ABCG2) in human colon cancer cell SW480.</p><p><b>METHODS</b>SW480 cells were treated with various concentrations of 5-FU. CCK8 assay was utilized to detect the 5-FU IC50 to SW480 cells. Positive expression of ABCG2 was detected by flow cytometry, and mRNA expression of ABCG2 was detected by real time polymerase chain reaction (RT-PCR).</p><p><b>RESULTS</b>The 5-FU IC50 to SW480 cells increased as the drug concentration increased (P<0.05). Flow cytometry revealed that positive expression rate of ABCG2 in normal SW480 cells (group A) was (6.26±0.86)%. Immediately after treatment with 5-FU for 48 hours, the positive expression rate of ABCG2 (group B) was (3.43±1.18)% (P<0.05). In the second passage of cells after treatment with 5-FU for 48 hours, the positive expression rate of ABCG2 (group C) was (12.91±3.42)% (P<0.05). The mRNA expression of ABCG2 detected by RT-PCR was in accordance with the results from flow cytometry.</p><p><b>CONCLUSION</b>Expression of ABCG2 in SW480 cells can be affected by various concentrations of 5-FU.</p>