Effects of CTEN on tamoxifen sensitivity, invasion and migration of estrogen receptor positive breast cancer cells

LU Xiangdong; ZHANG Tingrong; ZHAO Tao

doi:10.3969/j.issn.1009-0460.2018.02.002

Abstract：Objective To explore the effects of CTEN on tamoxifen sensitivity, invasion and migration of estrogen receptor(ER) positive breast cancer cells. Methods Lipofectamine 2000 liposomes were used to transfect MCF-7 cells with three pairs of plasmid vectors: CTEN over-expression plasmid pCMV-CTEN and control plasmid pCMV-Con, CTEN interference plasmid siCTEN and control plasmid siNC and HER-2 interference plasmid siHER-2 and control plasmid siNC. The mRNA and protein levels of CTEN and HER-2 were detected by real-time quantitative PCR and Western blotting, respectively. The proliferation of MCF-7 cells was detected by MIT as to evaluate tamoxifen sensitivity. Migration and invasive ability were detected by cell scratch test and Transwell test. Results The expression of CTEN and HER-2 in MCF-7 cells transfected with pCMV-CTEN were enhanced, while the expression of CTEN and HER-2 in MCF-7 cells transfected with siCTEN were weakened. In MCF-7 cells transfected with pCMV-CTEN, there were reduced sensitivity to tamoxifen, enhanced cell proliferation and increased migration rate and number of cells invaded to the lower chamber, while opposite results were found in terms of sensitivity to tamoxifen,cell proliferation,invasion and migration ability in MCF-7 cells transfected with siCTEN. The weakened tamoxifen sensitivity and enhanced cell proliferation and metastasis induced by CTEN could be reversed by interfering HER-2. Conclusion CTEN weakened tamoxifen sensitivity and enhanced cell proliferation, migration and invasion ability in human ER positive breast cancer MCF-7 cells, which may act through activating HER-2.