GMBP42在胃癌多药耐药中的逆转作用及机制研究

许文静+梁树辉+林涛+王飙落+徐宝宏+丁杰

[摘要] 目的 探讨GMBP42在胃癌多药耐药中的逆转作用及其分子机制。 方法 通过MTT实验检测GMBP42对胃癌多药耐药细胞SGC7901/VCR增殖的影响。体外药物敏感实验测定GMBP42致耐药细胞对化疗药物半数抑制浓度值（IC50）的影响。流式细胞仪检测GMBP42对阿霉素引起耐药细胞凋亡的影响。蛋白免疫印迹法（Western blot）检测GMBP42作用耐药细胞不同时间后MDR1（P-gp）、Bcl-2和Bax蛋白的表达水平。 结果 MTT实验显示，GMBP42本身不影響耐药细胞的增殖。体外药物敏感实验显示：GMBP42组与对照组相比，SGC7901/VCR细胞对化疗药物IC50值均降低（P < 0.05）。流式细胞检测表明：在相同剂量阿霉素作用下，GMBP42组中SGC7901/VCR凋亡率显著高于对照组（P < 0.05）。Western blot结果显示：GMBP42组与对照组相比，与SGC7901/VCR细胞作用12 h后MDR1（P-gp）和Bcl-2蛋白的表达水平明显降低，Bax蛋白的表达水平明显升高。 结论 GMBP42对耐药细胞的增殖本身无影响，可降低部分化疗药物IC50值，促进细胞凋亡。此作用可能与改变凋亡相关蛋白，上调Bax和下调Bcl-2的表达，降低耐药相关膜分子MDR1（P-gp）的表达有关。

[关键词] 胃癌；GMBP42；多药耐药；逆转耐药

[中图分类号] R735.2 [文献标识码] A [文章编号] 1673-7210（2017）03（c）-0008-04

Reversal effect and mechanism of GMBP42 on drug resistance in gastric cancer

XU Wenjing1 LINAG Shuhui2 LIN Tao3 WANG Biaoluo2 XU Baohong1 DING Jie2

1.Department of Digestive Diseases， Beijing Luhe Hospital， Capital Medical University， Beijing 101101， China； 2.Xijing Hospital of Digestive Diseases， Fourth Military Medical University State Key Laboratory of Cancer Biology， Shaanxi Province， Xi'an 710032， China； 3.Department of Digestive Diseases， 451 Hospital of PLA， Shaanxi Province， Xi'an 710054， China

[Abstract] Objective To investigate the reversal effect and molecular mechanism of GMBP42 in multidrug resistanceof gastric cancer. Methods The effect of short peptide GMBP42 on the proliferation of gastric cancer MDR cell line SGC7901/VCR was detected by MTT assay； In vitro drug sensitivity assay was applied to detect the effect of IC50 value （the half maximal inhibitory concentration） of MDR cell incubated with GMBP42； flow cytometry was used to detect the effect of GMBP42 combined with adriamycin on apoptosis of gastric cancer cells； Western blot was performed to detect the expression levels of MDR1 （P-gp）， Bcl-2 and Bax proteins on MDR cells incubated with peptide GMBP42 after different times. Results The results of MTT assays showed that GMBP42 had no influence on the proliferation of MDR cells compared with control group. In vitro drug sensitivity assay showed that peptide GMBP42 could decrease the IC50 valueof MDR cellcompared with the control group （P < 0.05）. The results of flow cytometry showed that the apoptosis rate of SGC7901/VCR under the same dose of adriamycin was significantly higher than that of control group （P < 0.05）. The results of Westernblot showed that the expression of MDR1 （P-gp） and Bcl-2 protein in SGC7901/VCR cells incubated with GMBP42 after 12 h was significantly up-regulated， and the expression level of Bax protein was significantly down-regulated. Conclusion GMBP42 has no influence on the proliferation of MDR cells. GMBP42 can decrease the IC50 value and promote the apoptosis of MDR cells. The effect of reverse MDR was implemented through change the expression of apoptosis related proteins contain up-regulation of Bax and down-regulation of Bcl-2 expressions，other through down-regulating the expression of MDR related molecule （MDR1）.