Effect of mineral dust-induced gene on the sensitivity of lung cancer cells to cisplatin

Abstract

Objective To investigate the effect of mineral dust-induced gene (mdig) on the sensitivity of lung cancer cells to cisplatin (DDP). Methods The expression of mdig mRNA and protein in A549 and DDP-resistant A549 cells (A549/DDP) were detected by real-time quantitative PCR and Western blot, then the mdig was further silenced and over-expressed in A549 cells.The CCK-8 assay was used to detect the proliferation of cells treated with different concentrations of DDP, and then to evaluate the sensitivity changes of DDP to calculate the half inhibitory concentration (IC50) of DDP. Results The mRNA and protein expression of mdig in A549/DDP cells were significantly higher than those in A549 cells (t=4.8, 9.7, both P<0.01), and the IC50 value of cisplatin in A549/DDP cells was significantly higher than that in A549 cells [(93.8±8.7) mg/L vs (29.9±1.4) mg/L, t=12.6, P<0.01], drug resistance coefficient was 3.14.Compared with the lentivirus control group, the IC50 value of the mdig-overexpressing A549 cells (LV-mdig) was significantly increased [the LV-mdig group (176.9±13.4) mg/L vs the Vector group (37.5±2.0) mg/L, F=309.0, P<0.01], while the IC50 value of mdig-knockdown A549 cell group (LV-mdig RNAi) was significantly decreased [the LV-mdig RNAi group (10.8±1.4) mg/L vs the LV-con group (26.7±1.1) mg/L, F=146.7, P<0.01]. Conclusions Mdig can reduce the sensitivity of lung cancer cells to cisplatin, resulting in resistance to DDP. Key words: Lung neoplasms; Cisplatin; Drug resistance, neoplas; Mineral dust-induced gene