Abstract 2421: Iron deficiency suppresses EMT through down-regulation of N-cadherin in esophageal cancer.

Abstract

Abstract [Introduction] Epithelial-Mesenchymal-Transition(EMT) plays a great role in cancer metastasis and invasion. Mechanism of EMT still remains unclear, However E-cadherin and N-cadherin are known to have contribution to EMT. In particular, down-regulation of N-cadherin has been reported to reduce cancer metastasis and invasiveness. Iron metabolism and its relationship with cancer cell were studied for a long time. Iron overload is known to induce some kinds of cancer, and iron deficiency is also known to suppress the tumor growth in vivo study. But the correlation of iron metabolism and tumor progression isn't unclear. Recently, it was reported that iron metabolism was essential for EMT and iron deficiency down-regulated EMT differentiation. In this study, we hypothesized that iron deficiency down-regulated the expression of N-cadherin, and suppressed the ability of metastasis and invasiveness. Here we demonstrate our results. [Materials and Methods] In vitro study, TE-4 and TE-10 esophageal squamous cell carcinoma and OE19 esophageal adenocarcinoma cell line were used in this study. Cell viability was determined by XTT assay. Iron chelator deferasirox was used to simulate iron deficient condition. To determine that iron deficiency suppresses EMT and invasiveness of cancer cells, we investigated western blotting analysis, three-dimensional spheroid model analysis and migration assay. Moreover, to determine the expression N-cadherin in mRNA level, PCR assay was performed. In vivo study, iron depletion condition was made by iron deficient diet. Normal and iron deficient diet were fed for 3 weeks before implantation of TE-4 cells in athymic male nude mice(n=8/group). After implantation, each diet was fed continuously for a month. [Results] In vivo study, iron deficient diet suppressed the tumor growth(tumor volume: normal diet vs iron deficient diet = 30.7±1.1 mm3 vs 10.9±2.2 mm3). In vitro study, deferasirox reduces proliferation of all cell lines in a concentration manner. According to western blotting analysis, deferasirox induces reduction of N-cadherin protein in TE-4 and TE-10 cell lines. N-cadherin down-regulation declines invasiveness of TE-4 and TE-10 cell lines in the three-dimensional spheroid model analysis and migration assay. Real time PCR assay shows that down-regulation of N-cadherin is dependent on reduction of N-cadherin mRNA. [Conclusion] Iron controlled treatment can be a novel therapy for invasiveness of cancer under EMT. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 2421. doi:1538-7445.AM2012-2421