The Influence Of Cell Growth And Endocrine Therapeutic Effect Of Erbeta Trasfected Breast Cancer Cell Line MDA-MB-231

Breast Cancer is the leading killer of women's health. Hormone receptor negative breast cancer for ER alpha and PR expressing negative and considered ineffective of endocrine therapy and lead to poor prognosis. In 1996, Mosselman discovered another ER subtype named ERβand variant isoforms later. It soon became a hot research topic about Endocrine Therapy.According to the retrospective study, about 50% breast cancer patients are diagnosed expressing ERβ; it should be noticed that there are some patients with ERα-/ERβ+,so people doubt that Hormone receptor negative breast cancer is invalid with endocrine therapy. Attention has switched to ERβwhat will be the new target of Hormone receptor negative breast cancer with endocrine therapy. At present, there are some relevant researches at home and aboard with different results. Many factors disturb in experiments. Therefore, it is proposed that, in this experiment, we will try to verify ERβby the exclusion of other factors.Purpose:By the triple negative breast cancer cells transfecting ERβand its variant ERβ△, it is aimed to understand that its sole expression has reflection to the growth state of cancer cells , and estrogen, tamoxifen (the reactivity of tamoxifen) role; Discussing whether ERβmight be the hormone receptor negative breast cancer, especially the new target of triple negative breast cancer(TNB) in the endocrine therapy and its possible mechanism.Methods: (1) constructing eukaryotic cells express cloning (pReceiver -M72 -ERβand the pReceiver-M72-ERβ△.(2)Liposomes method trasfecting TNB breast cancer cell lines MDA- MB-231, setting four groups of ERβ, ERβ△group, empty vector group and controlled group. (3) 20 hours after transfection, using immunefluorescent, immunocytochemistry, Western Blot to validate the protein expression, added different drug concentrations of tamoxifen, estrogen(E2). (4) the detection of cells relatively growth active by MTT, Flow Cytometry(FCM) assay to observe Cell cycle.Results:(1) the successful construction of pReceiver - M72 -ERβand it's raviant pReceiver - M72– ERβ△which are reformed from IRES2 - EGFP. (2) transfecting MDA - MB - 231 cells after 20 hours, ERβand ERβ△expression was increased, and there is statistical difference between the transfected groups and untransfected group by calculation of grey level. (3) comparing with blank group and empty carrier, the growing speed of carrying ERβcells is fast; the ratio of the cell cycle of G1 phase decreases; the ratio of S period increases; the ability of cloning improves, but the function of Estrogen and tamoxifen are not clear.Conclusion:ERβexpressing along in no other subtypes and ERαthat promotes cancer growth, increasing cell relative growth activity and cloning formation ability; TNB cell lines MDA-MB-231 to estrogen and tamoxifen reactive not clear.