The Function Of Nanog On EMT In Gastric Cancer

Objectives This work aims to study the function of pluripotent stem factor Nanog on epithelial-mesenchymal transition(EMT) in gastric cancer and its influence on migration and invasion abilities of human gastric cancer cells, and to analyze the regulation function of Nanog on histone lysine demethylase KDM5 B. This study will provide basic evidence for clarifying occurrence and development mechanisms of gastric cancer.Methods The protein levels of Nanog,epithelial marker E-cadherin and mesenchymal marker N-cadherin were detected in gastric cancer by immunohistochemical method; The protein levels of Nanog,E-cadherin and N-cadherin in TGF-β1 induced MGC-803 cells, as well as the protein levels of E-cadherin, N-cadherin and KDM5 B in Nanog-overexpressed and Nanog-knockdowned MGC-803 cells, were detected by immunocytochemistry method; The m RNA levels of Nanog and KDM5 B in Nanog-overexpressed and Nanogknockdowned MGC-803 cells were detected by real-time quantitative PCR; The protein levels of Nanog in Nanog-overexpressed and Nanog-knockdowned MGC-803 cells were detected by Western blot; Morphological changes of MGC-803 cells were observed in Nanog-overexpressed and Nanog-knockdowned MGC-803 cells stained with HE; Migration and invasion of MGC-803 cells in Nanog-overexpressed and Nanogknockdowned MGC-803 cells were detected by scratch test and Transwell assay.Results 1 The expression levels of E-cadherin in cancer tissues and metastatic lymph nodes were all significantly lower than in adjecent tissues(P<0.05). The protein levels of N-cadherin and Nanog in cancer tissues and metastatic lymph nodes were significantly higher than that in adjacent tissues(P<0.05, P<0.05). 2 The protein level of E-cadherin was markedly reduced(P<0.05), whereas the protein levels of N-cadherin and Nanog were significantly increased in TGF-β1 induced MGC-803 cells(P<0.05, P<0.05). 3 The Nanog-overexpressed MGC-803 cells arranged loosely with characteristics of mesenchymal cell. Compared with the control cells, the protein level of E-cadherin in Nanog-overexpressed MGC-803 cells was markedly reduced(P<0.05). Whereas the protein levels of N-cadherin and KDM5 B were markedly increased(P<0.05, P<0.05). The migration and invasion abilities of MGC-803 cells were all signifcantly enhanced(P<0.05, P<0.05). 4 The Nanog-knockdowned MGC-803 cells arranged rulely with characteristics of epithelial cell.Compared with the control cells, the protein level of Ecadherin in Nanog-knockdowned MGC-803 cells was markedly increased(P<0.05). Whereas the protein levels of N-cadherin and KDM5 B were markedly reduced(P<0.05, P<0.05). The migration and invasion abilities of MGC-803 cells were all signifcantly weakene(P<0.05, P<0.05).Conclusions 1 Nanog is hypoexpressed in gastric tissues and cells occurred EMT. 2 Nanog positively regulates EMT, migration and invasion of gastric cancer cells. 3 Nanog regulates the expression of histone lysine demethylase KDM5 B positively in gastric cells.