Role Of PRMT2β On MCF-7 Cell Proliferation And Its Relevant Mechanism

Objective: To explore the effect of PRMT2β on MCF-7 cells proliferation and its underlying mechanism, in order to provide new insights into targeted breast cancer therapy.Methods: Through microscopic observation and Western Blotting analysis, we had identified the MCF-7 cell line which was stablely transfected with PRMT2β. The experimental group was PRMT2β overexpression group(over expression, OE)which had been treated with DOX(doxycyline) for 48 h, and the DOX untreated group(negative control, NC) was used as negative control. The above-mentioned cells were applied in our experiments. To test the cell proliferation rate and cloning ability through MTT assay and colony formation assay respectively. Flow Cytometry was carried out to detect the cell apoptosis rate and cell cycle. Western Blotting analysis was used to detect the effect of PRMT2β on CCND1 expression and phosphorylation level of Akt in MCF-7 cells at the protein level.Results: 1. Microscopically, compared with the NC group, the OE group cells showed the shape of fusiform and had a relatively low cell density; Western blot analysis revealed that the DOX could induce the over expression of PRMT2β-3Flag fusion protein, indicated that PRMT2β-MCF7 stable cell line had been constructed successfully.2. MTT assay revealed that, compared with the NC group, the OE group cells had a relatively low cell proliferation rate, with statistical significance(P<0.05),suggested that PRMT2β could inhibit the proliferation of MCF-7 cell line.3. Colony formation assay showed that, compared with the NC group, the cloning ability of OE group cells had decreased,suggested that PRMT2β could inhibit the proliferation of MCF-7 cell line.4. Flow cytometry results showed that, compared with the NC group, the OE group had an increasing apoptosis rate and its cell cycle was relatively suppressed, both with statistical significance(P<0.05),indicated that PRMT2β could promote the apoptosis of MCF-7 cells and prolong the cell cycle, thus to inhibit cell proliferation.5. Western blot analysis revealed that, compared with the NC group, the expression level of CCND1 in OE group cells was down regulated and the phosphorylation level of Akt was decreased(P<0.05). When treated NC group and OE group cells with PI3K/Akt pathway inhibitors(LY294002 and Wortmannin), compared with its own control group respectively, two inhibitors could down regulate the expression of CCND1 and the phosphorylation level of Akt(P<0.05).Conclusion: PRMT2β could suppress the proliferation of MCF-7 cells, and the mechanism may related to that PRMT2β could down regulate the expression of CCND1 and the phosphorylation level of Akt.