許文靜+梁樹輝+林濤+王飆落+徐寶宏+丁杰

[摘要] 目的 探討GMBP42在胃癌多藥耐藥中的逆轉(zhuǎn)作用及其分子機制。 方法 通過MTT實驗檢測GMBP42對胃癌多藥耐藥細胞SGC7901/VCR增殖的影響。體外藥物敏感實驗測定GMBP42致耐藥細胞對化療藥物半數(shù)抑制濃度值（IC50）的影響。流式細胞儀檢測GMBP42對阿霉素引起耐藥細胞凋亡的影響。蛋白免疫印跡法（Western blot）檢測GMBP42作用耐藥細胞不同時間后MDR1（P-gp）、Bcl-2和Bax蛋白的表達水平。 結(jié)果 MTT實驗顯示，GMBP42本身不影響耐藥細胞的增殖。體外藥物敏感實驗顯示：GMBP42組與對照組相比，SGC7901/VCR細胞對化療藥物IC50值均降低（P < 0.05）。流式細胞檢測表明：在相同劑量阿霉素作用下，GMBP42組中SGC7901/VCR凋亡率顯著高于對照組（P < 0.05）。Western blot結(jié)果顯示：GMBP42組與對照組相比，與SGC7901/VCR細胞作用12 h后MDR1（P-gp）和Bcl-2蛋白的表達水平明顯降低，Bax蛋白的表達水平明顯升高。 結(jié)論 GMBP42對耐藥細胞的增殖本身無影響，可降低部分化療藥物IC50值，促進細胞凋亡。此作用可能與改變凋亡相關(guān)蛋白，上調(diào)Bax和下調(diào)Bcl-2的表達，降低耐藥相關(guān)膜分子MDR1（P-gp）的表達有關(guān)。

[關(guān)鍵詞] 胃癌；GMBP42；多藥耐藥；逆轉(zhuǎn)耐藥

[中圖分類號] R735.2 [文獻標識碼] A [文章編號] 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）.