Institute of Immunology, Medical Faculty, RWTH Aachen University, Pauwelsstraße 30, D-52074 Aachen, Germany.
Int J Mol Sci. 2022 Feb 18;23(4):2270. doi: 10.3390/ijms23042270.
Zinc has been suggested to play a role in carcinogenesis and tumor progression. Serum zinc levels of lung cancer patients are for example lower than in healthy individuals. The activation and expression of the epidermal growth factor receptor (EGFR), which plays a role in tumor biology, are presumably influenced by zinc. EGFR activation influences cell adhesion and immune escape. This study provides insights into the impacts of zinc on the EGFR activation and expression of downstream proteins such as E-cadherin and PD-L1 in the alveolar carcinoma cell line A549. To model chronic changes in zinc homeostasis, A549 cells were cultured in media with different zinc contents. EGFR surface expression of unstimulated and stimulated A549 cells was determined by flow cytometry. EGFR phosphorylation as well as the protein expression of E-cadherin and PD-L1 were analyzed by Western blot. In our hands, chronic zinc deficiency led to increased EGFR surface expression, decreased E-cadherin protein expression and increased PD-L1 protein expression. Zinc supplementation decreased EGFR surface expression and PD-L1 protein expression. In summary, zinc-deficient A549 cells may display a more malignant phenotype. Thus, future clinical research should further focus on the possible benefits of restoring disturbed zinc homeostasis, especially in lung cancer patients.
锌被认为在致癌作用和肿瘤进展中发挥作用。例如,肺癌患者的血清锌水平低于健康个体。表皮生长因子受体(EGFR)的激活和表达在肿瘤生物学中起作用,据推测受锌的影响。EGFR 激活影响细胞黏附和免疫逃逸。本研究探讨了锌对肺泡癌细胞系 A549 中 EGFR 激活和下游蛋白如 E-钙黏蛋白和 PD-L1 表达的影响。为了模拟锌稳态的慢性变化,用不同锌含量的培养基培养 A549 细胞。通过流式细胞术测定未刺激和刺激的 A549 细胞的 EGFR 表面表达。通过 Western blot 分析 EGFR 磷酸化以及 E-钙黏蛋白和 PD-L1 的蛋白表达。在我们的研究中,慢性缺锌导致 EGFR 表面表达增加,E-钙黏蛋白蛋白表达减少,PD-L1 蛋白表达增加。锌补充剂降低了 EGFR 表面表达和 PD-L1 蛋白表达。总之,缺锌的 A549 细胞可能表现出更恶性的表型。因此,未来的临床研究应进一步关注恢复失调的锌稳态的可能益处,特别是在肺癌患者中。