人A-549细胞中锌与锌转运体表达的关系

Relationship between zinc and zinc transporter expression in human lung cancer cells

目的:通过ZnCl2和膜渗透性特异锌螯合剂(TPEN)处理人肺癌细胞株A-549,观察高锌和低锌条件下锌转运体在mRNA水平的表达情况。方法:0、50、100、150、200μmol/LZnCl2以及0、5、10、15、20μmol/LTPEN分别处理人肺癌细胞株A-549细胞12h,细胞存活率用MTT(噻唑蓝)方法检测;zinquin(荧光锌离子探针)检测细胞内锌离子含量;RT-PCR方法检测锌转运体mRNA的表达。结果:ZnCl2浓度为150μmol/L和200μmol/L以及TPEN对A-549细胞均有明显抑制生长作用;ZnCl2处理后的A-549细胞内锌离子含量显著升高,TPEN处理的A-549细胞内锌离子含量降低。与对照组相比,ZnCl2处理的细胞ZnT-1(锌转运体)mRNA表达量普遍升高;TPEN处理的细胞ZnT-1mRNA表达水平依次降低;ZIP-1(锌铁调控样蛋白)mRNA的表达水平随ZnCl2浓度增加而依次降低,随TPEN浓度的增加而依次升高;ZIP-10mRNA的表达水平随ZnCl2浓度增加而依次降低,TPEN处理后普遍增加。结论:高锌促进人肺癌A-549细胞ZnT-1mRNA的表达,抑制ZIP-1和ZIP-10mRNA的表达;低锌促进人肺癌A-549细胞ZIP-1和ZIP-10mRNA的表达。

AIM： To study the changes of zinc transporter gene expression in A -549 cell line exposed to ZnCl2 and N, N, N＇, N＇-tetrakis 2 -pyridytmethyl ethylenediamine （TPEN）. METHODS： Human lung cancer cell line A -549 was exposed to different concentrations of ZnCl2 （0, 50, 100, 150,200 μmol/L） and TPEN （0, 5, 10, 15, 20 μmol/L）, respectively. Twelve hours later, the cell viability was measured by MTT （methyl thiazolyl tetrazolium） and levels of zinc transporter mRNA was detected by RT - PCR. Zinquin was used to estimate the intracellular zinc concentrations. RESULTS ： A -549 cell viability rate was significantly decreased when exposed to ZnCl2 at concentrations of 150 and 200μmol/L, and to TPEN. The intracellular zinc concentration was significantly increased when exposed to ZnCl2 and decreased when exposed to TPEN. Zinc transporter （ZnT - 1 ） mRNA level was increased along with the increase in the concentration of ZnCl2 but decreased when exposed to TPEN. The expressions of ZIP- 1 and ZIP- 10 （Zrt -and Irt -like protein） were increased along with the increase in the concentration of TPEN but decreased when exposed to ZnCl2. CONCLUSION： ZnT - 1 expression is induced by zinc supplement. ZIP - 1 and ZIP - 10 expressions are induced by zinc deficiency and repressed by zinc supplement.