核心蛋白聚糖对膀胱癌细胞生长抑制机制的研究

目的 探讨核心蛋白聚糖（DCN）对膀胱癌细胞生长的影响。方法 以膀胱癌T24细胞株为研究对象，采用MTT法检测不同浓度、不同时间的DCN对T24细胞存活率的作用，采用流式细胞术分析DCN对T24细胞周期及凋亡的影响，采用ELISA和Western blot法检测DCN对转化生长因子-β1（TGF-β1）和P21蛋白表达的影响。结果 与其他浓度相比，40、50 μg/mL DCN作用72 h时对T24细胞的抑制作用最强，差异有统计学意义（P<0.05），且G1期细胞达到最高值，S期细胞达最低值（P<0.001）。5、10、20、30、40、50 μg/mL DCN作用72 h后均能促进T24细胞凋亡，且在40 μg/mL时达到最大值(P<0.001)；与0 μg/mL相比，5、10、20、30、40、50 μg/mL DCN作用72 h对TGF-β1表达均有抑制作用, 最明显的抑制作用浓度为40 μg/mL(P<0.001)；与0 μg/mL相比，40 μg/mL DCN能促进P21蛋白上调（P<0.001）。结论 DCN在体外能够抑制膀胱癌T24细胞生长，诱导其凋亡，其可能的作用机制为下调TGF-β1及上调P2l蛋白表达。

Effects and mechanism of decorin on the proliferation of T24 bladder adenocarcinoma cells in vitro

Objective  To investigate effects and mechanism of decorin(DCN) on the proliferation of T24 bladder adenocarcinoma ceIls in vitro.Methods  Bladder cancer T24 cell line was used as the research object. MTT assay was used to detect the effect of different concentrations and time of DCN on the survival rate of T24 cells. Flow cytometry was used to analyze the effect of DCN on the cell cycle and apoptosis of T24 cells. ELISA and Western blot were used to detect the expression of transforming growth factor-β1 (TGF-β1) and P21 protein by DCN.Results  Compared with other concentrations, after T24 cells were treated with DCN at 40 and 50 μg/mL for 72 h, the inhibitory effect of DCN on T24 cells reached its maximum level（P<0.05）, the G1 phase cells increased the peak and the S phase cells decreased the lowest （P<0.001）, and the G2 phase remained unchanged throughout the treatment. When T24 cells were treated with DCN of 5, 10, 20, 30, 40 and 50 μg/mL after 72 h, there were apoptosis effect, but reached the maximum at 40 μg/mL （P<0.001）, and compared with 0 μg/mL, the DCN at 5, 10, 20, 30, 40 and 50 μg/mL after 72 h was significantly inhibited expression of TGF-β1, but the most obvious inhibitory concentration was 40 μg/mL (P<0.001). After T24 cells were treated with DCN at 40 μg/mL for 72 h, Western blot with rabbit anti-P21 antibody showed that P21 protein was up-regulated compared with 0 μg/mL(P<0.001).Conclusions  Decorin can inhibit adenocarcinoma cell proliferation and induce apoptosis of adenocarcinoma cells in vitro. The pro1iferation of T24 cell could be inhibited in vitro by decorin through the mechanism of decreasing TGF-β1，increasing P21 protein expression，inhibiting cell cycle and inducing cell apoptosis.