去整合素和金属蛋白酶17调控胰腺癌细胞增殖凋亡的机制

Mechanisms of ADAM17/TACE regulating proliferation and apotosis of pancreatic ductal adenocarcinoma cells

目的探讨去整合素和金属蛋白酶17（ADAM17／TACE）调控胰腺癌细胞增殖凋亡的作用机制。方法分别采用免疫组织化学及流式细胞仪检测58例胰导管腺癌组织及6株胰腺癌细胞株中ADAM17／TACE的表达，用小RNA干扰（siRNA）技术去除胰腺癌细胞k3．6plADAM17／TA—CEmRNA及蛋白表达后，CCK-8试剂盒检测胰腺癌细胞L3．6pl的生长速度，Westernblot检测AD—AM17／TACE、凋亡相关基因PARP、增殖相关基因p27（p27kip1）表达。阻断表皮生长因子受体（EG—FR）及丝氨酸苏氨酸蛋白激酶（AKT）通路后，Westernblot检测ADAM17／TACE及EGFR／p—EGFR、AKT／p-AKT的表达变化。结果58例胰导管腺癌组织及6株胰腺癌细胞中ADAM17／TACE的表达阳性率均为100％。同亲代L3．6pl细胞比较，siRNA干扰ADAM17／TACEmRNA的表达后，L3．6pl细胞生长速度减缓（P〈0．05）；p27kip1的表达明显增强；多聚二磷酸腺苷核糖聚合酶（PARP）表达亦明显增强提示出现凋亡；分别阻断EGFR和磷脂酰肌醇3激酶（P13K）／AKT信号通路后，AD—AM17／TACE蛋白表达均增加。结论ADAM17／TAcE调控胰腺癌细胞增殖，抑制其表达可致胰腺癌细胞凋亡，可能与P13K／AKT信号通路相关。

Objective To study the mechanisms of ADAM17/TACE regulating proliferation and apoptosis of pancreatic ductal adenocarcinoma cells. Methods The expression of ADAM17/TACE in 58 cases of pancreatic ductal adenocarcinoma tissues and 6 pancreatic cancer cell lines were detected by using immunohistochemistry and FACS. After small interfering RNA （siRNA） to block the expression of AD- AM17/TACE, cell proliferation and apoptosis were analyzed by using CCK-8 Kit and poly （ADP-ribose） polymerase （PARP） Western blotting. After inhibiting epidermal growth factor receptor （EGFR） and AKT passway, the expression levels of ADAM17/TACE and EGFR/p-EGFR, AKT/p-AKT were detected by u- sing Western blotting. Results The positive ratio of ADAM17/TACE expression was 100% in 58 cases of pancreatic ductal adenocarcinoma tissues and 6 pancreatic cancer cell lines. The results of CCK-8 assay indicated the proliferation of L3.6pl cancer cell was markly slower after transfering siRNA to block the expression of ADAM17/TACE mRNA （P 〈 0. 05 ）. The results of Western blotting revealed that the expression of ADAM17/TACE was down-regulated by ADAM17/TACE-siRNA in 13.6pl cancer cells, but the expression of p27kip1 and PARP markedly up-regulated after the 13.6 cancer ceils treated with siRNA. After inhibition of the EGFR-phosphatidylinositol 3 kinase （PI3K）/AKT signaling pathway, the expression of ADAM17/TACE was increased by Western blotting. Conclusion It is suggested that ADAM17/TACE could modulate proliferation of pancreatic cancer ceils and blocking ADAM17/TACE expression could induced apoptosis of pancreatic cancer ceils probably via EGFR-PI3K/AKT pathway.