γ-氨基丁酸对胆管癌细胞QBC939生长抑制及其机制探讨

Inhibition effect of GABA on the growth of cholangiocarcinoma cell QBC939 and its mechanism

目的:探讨γ-氨基丁酸(γ-aminobutyric acid,GABA)抑制胆管癌细胞QBC939增殖的功能受体。方法:免疫组化法检测42例胆管腺癌和12例正常胆管组织标本GABAA R(β3)(A受体)、GABAB R(R1)(B受体)和GABAC R(ρ2)(C受体)的表达情况;不同浓度的GABA、GABA+荷包牡丹碱(A受体拮抗剂)、GABA+phaclofen(B受体拮抗剂)孵育胆管癌细胞QBC939 48h,采用MTT和AnnexinⅤ-FITC/PI双染流式细胞术检测细胞的增殖及凋亡。结果:42例胆管癌组织中GABAB R(R1)阳性表达率为61.9%(26/42),12例正常胆管组织中GABAR(R1)阳性表达率为16.7%(2/12),差异有统计学意义,χ2=7.651,P=0.006。MTT和流式细胞术检测结果显示,GABA能明显抑制胆管癌细胞QBC939的增殖并促进其凋亡,但此效应可被phaclofen拮抗,而荷包牡丹碱则不能。对照组细胞增殖抑制率和凋亡率分别为0和(4.32±0.28)%;100μmol/L GABA组细胞增殖抑制率和凋亡率分别为(15.30±0.80)%和(23.15±0.21)%;100μmol/L GABA+100μmol/L荷包牡丹碱组细胞增殖抑制率和凋亡率分别为(14.23±0.57)%和(22.93±0.37)%;100μmol/L GABA+100μmol/L phaclofen组细胞增殖抑制率和凋亡率分别为(2.66±0.74)%和(4.30±0.69)%。结论:GABA可能通过GABAB受体介导抑制胆管癌细胞的增殖。

OBJECTIVE：To explore 7-aminobutyric （GABA） through which receptors mediate the proliferation and apoptosis of the cholangiocarcinoma cell QBC939. METHODS： Expressions of GABAAR （133）, GABABR （RI） and GABAcR （92） were detected by immunohistochemistry QBC939 cell lines were cultured in different groups and treated with GABA,GABA＋ bicuculine（A receptor antagonist）, GABAq- phaclofen（B receptor antagonist ）for 48 hours. MTT and Annexin V-FITC/PI binding assays were used to detect the proliferation and apotosis of QBC939 cells. RESULTS： Significant difference was only observed in GABABR （RI） expression between 42 cholangiocarcinoma and 12 non-tumor cases [-61.9 % （26/42） vs 16.7 % （2/12）, X2= 7.651, P 〈 0. 006]. MTT and FCW assays showed that GABA inhibited the proliferation of QBC939 cells and induced its apoptosis and the effect could be antagonized by phaclofen, but not bicuculine. The four groups （control group, 100 μmol/L GABA, 100 μmol/LGABA＋ 100 mol/Lbicuculine, 100 μmol/LGABA＋ 100 μmol/L phaclofen） showed different inhibiting rates which were 0, （15.30-±0. 80）%, （14. 23 ±0.57）% and （2.66 ±0.74）% and differ ent apoptosis rates which were （4.32±0. 28）%, （23.15±0.21）%, （22.93±0. 37） and （4. 30±0. 69）% ,respectively. CON- CLUSION： GABA may inhibit the growth of cholangiocarcinoma cells through GABA receptor.