Construction of plvx-cyclooxygenase-2-DsRed vector and its effects on proliferation in cyclooxygenase-2 overexpressed breast cancer cell line / 肿瘤研究与临床

ABSTRACT

Objective To construct plvx-cyclooxygenase-2(COX-2)-DsRed and establish breast cancer cell line MCF7 which overexpressed COX-2, to explore the effect of COX-2 on breast cancer cell.Methods The full-length COX-2 PCR product was obtained by total COX-2 PCR primers and COX-2 cDNA vector.After the PCR product and lentiviral vector plvx-DsRed-Monomer-N1 were cut simultaneously by restriction enzyme BamH1 and Xholl, they were connected and sequenced, to get lentiviral vector plvx-COX-2-DsRed.After selected by puromycin, overexpressed COX-2 breast cancer cell line MCF7-plvx-COX-2-DsRed was obtained.The stable cell line was verified by real time PCR and Western blot.The differences of proliferation ability between stable cell line and normal one were compared by colony formation test and Western blot.Results The lentiviral vector plvx-COX-2-DsRed and stable cell line MCF7-plvx-COX-2-DsRed after selecting were obtained.COX-2 expression level of the stable cell line was 75.29 times as high as that of MCF7, and 64.91 times as high as that of cell line MCF7-plvx-DsRed-Monomer-N1 by PCR assay (P ＜ 0.05), which was consistent with the results of Western blot and microscope photo.MTT results showed that cell line MCF7-plvx-COX-2-DsRed had grown faster than cell line MCF7 and MCF7-plvx-DsRed-Monomer-N1 from the 2nd day (P ＜ 0.05), which was accordant with colony formation assay.MCF7-plvx-COX-2-DsRed cell line had higher c-myc expression and lower β-catenin expression than MCF7 cell and cell line MCF7-plvx-DsRed-Monomer-N1 detected by Western blot relative quantification (P ＜ 0.05).Conclusion The plvx-COX-2-DsRed lentiviral vector and cell line MCF7-plvx-COX-2-DsRed are successfully constructed.COX-2 can increase proliferation of MCF7 cells through up-regulating the expression of c-myc.