Pokemon基因表达与胃癌耐药性的关系

目的 探讨okemon基因表达与胃癌细胞药敏性及耐药基因的关系.方法 取60例胃癌组织和癌旁组织石蜡标本,采用免疫组化技术检测组织中pokemon蛋白及耐药相关蛋白P-糖蛋白(P-gp)、多药耐药相关蛋白1(MRP1)、肺耐药蛋白(LRP)、生存素(survivin)的表达,并分析pokemon蛋白与其他4种蛋白的关系.采用磺酰罗丹明B(SRB)蛋白染色法检测5-氟尿嘧啶(5-FU)、顺铂(DDP)、奥沙利铂(L-OHP)对胃癌细胞株SGC7901、胃癌耐药细胞株SGC7901/ADR、胃上皮细胞株GES-1的抑制作用;qPCR及蛋白质印迹法检测上述3种细胞株中pokemon和耐药基因的表达.合成针对pokemon的siRNA并转染SGC7901/ADR细胞,检测转染前后SGC7901/ADR细胞的化疗药敏性及耐药基因的变化.结果 胃癌组织中pokemon、P-gp、MRP1、LRP、survivin蛋白的阳性表达率均高于癌旁组织(P＜0.05);pokemon蛋白表达与P-gp、survivin蛋白表达间存在正相关关系(r=0.385 2,P=0.002;r=0.342 4,P=0.007).Pokemon、P-gp、MRP1、survivin蛋白在SGC7901/ADR细胞株中的表达高于细胞株SGC7901及GES-1;SGC7901/ADR细胞株的耐药性最强,SGC7901次之,GES-1最弱(P＜0.01).Pokemon-siRNA转染SGC7901/ADR细胞后细胞中pokemon mRNA的表达明显受到抑制;转染后化疗药物对细胞的抑制能力增强,P-gp、survivin表达减弱(P＜0.05).结论 Pokemon与P-gp、survivin通过相互调控而促进胃癌耐药性的形成.Pokemon可能成为胃癌靶向治疗的候选基因.

Relationship between pokemon gene expression and drug resistance of gastric carcinoma

Objective To explore the relationship and significance between expression of Pokemon and chemosensitivities and drug related genes in gastric cancer cells. Methods 60 paraffin embedded cases of gastric cancer and para-carcinoma tissues were collected, and immunohistochemistry(IHC) was applied to detect Pokemon, P-gp, MRP1, LRP, Survivin proteins in gastric cancer and para-carcinoma tissues, then relationship between Pokemon protein and drug related proteins was analyzed, Chemosenisitivities of 5-FU, DDP, L-OHP to SGC7901, drug resistant cell line SGC7901/ADR, and gastric epithelial cell line GES-1 were tested with SRB assay. Real time quantitative PCR and Western blot assay were applied to test expression of Pokemon and drug related genes in 3 cell lines. Then Pokemon-siRNA was synthetized and transfected into SGC7901/ADR, and effect for transfection was tested. Chemosenisitivities and drug resistance genes were compared in Pokemon-siRNA transfection group and control group . Results Expressions of Pokemon, P-gp, MRP1, LRP, Survivin were stronger in gastric cancer tissues than in para-carcinoma tissues (P<0.05). Positive corelation was evaluated between Pokemon and P-gp, Pokemon and Survivin (P<0.05). Expressions of Pokemon, P-gp, MRP1, Survivin were stronger in SGC7901 and SGC7901/ADR cells than in GES-1, and strongest drug resistance was verified in SGC7901/ADR cells, following by SGC7901, GES-1 cells. (P<0.05) Pokemon mRNA in SGC7901/ADR was significantly inhibited after Pokemon-siRNA transfection, and the inhibition of chemotherapy agents to SGC7901/ADR cells increased, then expressions of P-gp, Survivin were down-regulated simultaneously (P<0.05). Conclusions Pokemon was involved in drug resistance of gastric cancer by mutual regulation with P-gp, Survivin, and Pokemon might be as a candidate gene for gastric cancer target treatment.