Abstract:

Objective To investigate the impacts of prolactininducible protein （PIP） downregulation on cell abilities of migration， adhesion and invasion of human breast cancer MDA-MB-453 cells. Methods PIP-siRNA， control-siRNA and blank-siRNA were transfected into human breast cancer MDA-MB-453 cells through liposome as experiment group， negative control group and blank control group， respectively. The transfection efficiency was observed by fluorescence microscope. Forty-eight hours after transfection， reverse transcription PCR and immunocytochemistry were employed to detect the expression of PIP in 3 groups. Cell experiments were performed to assess cell migration， adhesion and invasion respectively， when PIP-siRNA was transfected into MDA-MB-453 cells for 48 hours. Results The transfection efficiency of MDA-MB-453 cells was 90％. PIP mRNA and PIP protein expression of PIP-siRNA group were 0.035±0.003 and 483.3±59.8， which were significantly lower than those of control-siRNA group and blank-siRNA group（P＜0.05）. The number of migrated cells in PIP-siRNA group was 21.0±5.3， fewer than those of control-siRNA group and blank-siRNA group（P＜0.05）； compared with control-siRNA group， the adhesion rate at 30 and 60min were decreased by （42.6±2.7）％ and （48.5±3.1）％ with statistical significance（P＜0.05）. Moreover， the number of invaded cells in PIPsiRNA group was 31.0±4.2， significantly fewer than those of control-siRNA group and blank-siRNA group（P＜0.05）. Conclusion Down-regulation of PIP expression in MDA-MB-453 cells can inhibit the abilities of migration，adhesion and invasion， which suggests that PIP plays an important role in the metastatic potency of breast cancer cells.