Relationship between zinc and zinc transporter expression in breast cancer MCF-7 cells

AIM: To study the changes of zinc transporter gene expression in MCF-7 cell line exposed to ZnCl₂ and TPEN. METHODS: Human breast cancer cell line MCF-7 was exposed to different concentrations of ZnCl₂ (0, 50, 100, 150, 200 μmol/L) and TPEN (0, 5, 10, 15 μmol/L), respectively. Twelve hours later, the cell viability was measured by MTT and levels of zinc transporter mRNA by RT-PCR. Zinquin was used to estimate the intracellular zinc concentrations. RESULTS: MCF-7 cells viability rate was significantly decreased when exposed to ZnCl₂ (with 150 μmol/L and 200 μmol/L) and TPEN. The intracellular zinc concentration was significantly increased when exposed to ZnCl₂ and decreased when exposed to TPEN. ZnT-1 mRNA level was increased along with the increasing concentration of ZnCl₂ but decreased when exposed to TPEN. The expressions of ZIP2 and ZIP10 were increased along with the increasing concentration of TPEN. CONCLUSION: ZnT-1 gene expression is induced by zinc supplement and repressed by zinc deficiency. ZIP2 and ZIP10 gene expressions are induced by zinc deficiency.