冈田酸对喉鳞癌细胞系PP2A活性及迁移的影响

Okadaic acid inhibits PP2A activities and cell migration of laryngeal squamous cell carcinoma Hep-2

目的:探讨冈田酸(OA)对喉鳞癌细胞系(Hep-2)活性和迁移能力的影响及其可能的作用机制。方法:采用四甲基噻唑蓝(MTT)比色实验确定OA作用于Hep-2的最大浓度;酶活性实验检测不同浓度(0、50、100 n mol/L)OA对Hep-2蛋白磷酸酶2A(PP2A)活性的影响;划痕实验检测Hep-2在不同浓度(0、50、100 nmol/L)OA作用下迁移能力的变化。结果:50、100、200 nmol/L OA作用24 h后Hep-2的相对活力分别为96.7%±1.8%、82.9%±12.6%和57.2%±7.7%,与对照组(100%)比较均明显下降(P均<0.05)。50和100 nmol/L OA作用24 h后PP2A的相对活性分别为30.90%±12.01%和8.98%±4.96%,与对照组(100%)相比明显下降(P<0.05)。划痕试验中,经OA作用24及48 h后Hep-2细胞的迁移能力与对照组相比均明显减弱(P<0.05),并且100 nmol/L OA处理组迁移能力的减弱程度较50nmol/L OA处理组更明显(P<0.05)。结论:100 n mol/L冈田酸明显抑制Hep-2细胞PP2A活性并降低了细胞的迁移能力。

OBJECTIVE：To investigate the mechanism of inhibition of Hep-2 cell migration by Okadaic acid（OA）. METHODS：MTT assay was used to determine the doses of OA for the investigation. Hep-2 cells were treatedwith 0,50 or 100 nmol/L OA and enzyme assay was used to measure PP2A activities. Wound scratch assay was used toobserve the influence of OA on migration of Hep-2. RESULTS：The growth inhibition ratio was 96.7%±1.8%,82.9%± 12.6% and 57.2%±7.7% in cells treated with 50,100 and 200 nmol/L OA,and the difference wassignificant （P〈0.05）. In cells treated with 50 and 100 nmol/L OA,the relative activity of PP2A was 30.90%±12.01% and8.98%±4.96% （P〈 0.05）. From the wound scratch assay,the treated cells took significantly longer than untreated cells forhealing （P〈0.05）. CONCLUSION：Inhibition of PP2A activities may be responsible for the reduction of migration in theOA-treated Hep-2 cells.