Objective To investigate the effects of RNA-interfered IQGAP1 gene on the sensitivity of esophageal squamous cell line KYSE150 to cisplatin(DDP) and the relevant mechanisms.

Methods Synthesized siRNA targeting IQGAP1 was transfected into KYSE150 cells. MTT assay was employed to observe the sensitivity of KYSE150 cells to cisplatin. Flow cytometry assay was used to detect the cell cycle proportion and apoptosis rate in the interference group, blank control group and negative control group. The expression of Nrf2 and MRP-1 protein in KYSE150 cells were detected by Western blot.

Results Transfection of siRNA could significantly inhibit the expression of IQGAP1 protein and mRNA in ESCC cell lines KYSE150. After cisplatin (1, 5, 10, 20) μmol/L treatment for 24 hours, cell survival rates in the interference groups were obviously decreased, compared with control groups(P < 0.05); flow cytometry showed that cells proportion in G₀/G₁ phase and apoptotic rate in the interference group were obviously increased, compared with control groups(P < 0.05); Western blot revealed that IQGAP1 gene silencing down-regulated the expression of Nrf2 and MRP-1 protein.

Conclusion The sensitivity of esophageal squamous carcinoma cells to cisplatin can be improved by siRNA-interfered expression of IQGAP1, and this effect may be achieved by down-regulating Nrf2 and MRP-1 protein expression.