抑制5-脂氧合酶表达对胰腺癌细胞增殖和凋亡的影响

Effects of inhibition of 5-lipoxygenase by RNA interference on proliferation and apoptosis of human pancreatic cancer cells

目的应用RNA干扰（RNAi）技术阻断5-脂氧合酶（5-LOX）的表达，观察其对人胰腺癌细胞SW1990增殖及凋亡的作用。方法构建4个靶向5-LOX的小干扰RNA（small interference,siRNA）和1个阴性对照siRNA质粒表达载体，采用Lipofectamine ^TM2000法转染SW1990细胞，RT．PCR和Western blot检测RNAi后SW1990细胞的5-LOX mRNA和蛋白表达，MTY法检测细胞的增殖抑制率，流式细胞仪检测细胞凋亡率。结果阴性对照和4个序列特异性的siRNA对SW1990细胞5-LOX mRNA表达的抑制率分别为（3．0±1．4）％、（18．8＋1．5）％、（53．5±2．3）％、（56．1±2．0）％、（52．4±2．5）％；5-LOX蛋白表达抑制率分别为（4．5±2．0）％、（18．1±2．5）％、（50．4±4．3）％、（48．9±4．4）％、（45．9±4．0）％。转染24h后癌细胞增殖抑制率分别为（2．1±1．0）％、（5．5±1．3）％、（11．9±1．2）％、（13．4±1．1）％、（13．8±1．3）％。；48h的增殖抑制率分别为（3．0±1．3）％、（16．0±2．2）％、（25．7±2．5）％、（25．3±3．1）％、（27．2±3．2）％。转染24h细胞凋亡率分别为（2．0±0．8）％、（5．3±1．0）％、（10．6±1．2）％、（12．4±1．0）％、（10．6±0．9）％；转染48h的凋亡率分别为（3．0±1．0）％、（7．1±1．1）％、（17．5±0．9）％、（21．5±1．1）％、（15．7±1．0）％。结论通过RNAi可以有效、特异地阻断SW1990细胞5-LOX的表达，并可以有效抑制肿瘤细胞的增殖，促进肿瘤细胞凋亡。

Objective To investigate the effects of inhibition of 5-LOX by RNA interference on proliferation suppression and apoptosis induction of pancreatic cancer cell line. Methods Plasmid expression vectors containing four 5-LOX siRNA array and one negative control array were established, resoectively, and were transfected into pancreatic cancer cell line SW1990 with Lipofectamine rM2000. Cell proliferation inhibition rate was measured by MTT assay; apoptotic rate was examined by flow cytometry. Results The inhibitory rate of expression of 5-LOX mRNA in negative control group and four 5-LOX siRNA groups was （ 3.0 ±1.4）%, （18.8±1.5）%, （53.5±2.3）%, （56.1 ±2.0）%, （52.4±2.5）%; the inhibitory rate of expression of 5-LOX protein was （4.5 ±2.0）%, （18.1 ±2.5）%, （50.4±4.3）%, （48.9±4.4）%, （45.9 ± 4.0） %. The inhibitory rates of cancer cell proliferation at 24 h and 48 h after the transfection were （2.1_±1.0）%, （5.5 ±1.3）%, （11.9±1.2）%, （13.4±1.1）%, （13.8 ±1.3）% and （3.0±1.3）%, （ 16.0 ± 2.2） %, （25.7 ± 2.5） % , （25.3 ± 3.1 ） % , （27.2 ± 3.2） % , respectively. The apoptotic rates at 48 h after the transfection were （3.0 ±1.0）%, （7.1 ±1.10%, （17.5 ±0.9）%, （21.5 ±1.1）%, （15.7 ±1.0） %, respectively. Conclusions The plasmid vector containing siRNA against 5-LOX could suppress 5- LOX expression in SW1990 cells effectively and specifically, and could inhibit proliferation and induce the apoptosis of pancreatic cancer cells.