Abstract: Objective To investigate the effects of CYP4Z1 RNAi lentiviral vector on CYP4Z1 mRNA expression, proliferation and MAPK signals of breast cancer cells. Methods The relative expression levels of CYP4Z1 in the MDA-MB-468, T-47D and MDA-MB-231 cells were detected by RT-PCR and Western blot. Three kinds of CYP4Z1 RNAi lentiviral vectors were constructed and infected into CYP4Z1 overexpression of breast cancer cells. Then, RT-PCR was used to screen out the CYP4Z1 RNAi lentiviral vector which could exert the best interference effect in breast cancer cells. The cells proliferation and the expression levels of MAPK signals of CYP4Z1 RNAi on breast cancer cells were detected by MTT methods and Western blot, respectively. Results The levels of CYP4Z1 mRNA and protein expression were highly in MDA-MB-468 cells than MDA-MB-231 and T-47D cells (P＜0.05). Three groups of CYP4Z1 RNAi recombinant lentiviral vectors were successfully constructed (LV-CYP4Z1-RNAi-1/2/3). CYP4Z1 mRNA expression levels were decreased in MDA-MB-468 cells after infected with the three groups of recombinant lentiviral vectors, and the reduction rate of known-down CYP4Z1 in LV-CYP4Z1-RNAi-2 group reach to 81% (P＜0.01). In addition, CYP4Z1-RNAi-2 significantly inhibited cells proliferation and the protein expression levels of p-ERK1/2 in MDA-MB-468 cells (P＜0.05). Conclusions CYP4Z1 RNAi lentiviral vector is successfully constructed and CYP4Z1-RNAi-2 remarkably suppresses MDA-MB-468 cells proliferation via downregulation of ERK1/2 signal.

Key words: Key words: CYP4Z1, MDA-MB-468, breast cancer, lentiviral expression vector