Activation Of Histamine H4 Receptors Decreases Epithelial-Mesenchymal Transition Progress And The Preliminary Discussion Of Potential Signalling Pathway In Breast Cancer

Objective:To investigate the expressions of histamine H4 receptor(H4R)in breast cancer tissue,the tissue adjacent to breast cancer and breast cancer cell lines and investigate the relation between H4R and epithelial-mesenchymal transition(EMT)in breast cancer cells.Method:1.The expressions of H4R in breast cancer tissue,the tissue adjacent to breast cancer were tested by immunochemistry staining and the breast cancer cell lines were tested by fluorescent immune staining.2.The expressions of H4R mRNA and protein in MCF-7 and T47D cell lines of breast cancer were tested in the method of Realtime-PCR and Western blot.3.We detected the influence of H4R agonist and antagonist on the expression of E-cadherin and Vimentin by Realtime-PCR and fluorescent immune staining in MCF-7 cell line.4.We used Realtime-PCR to verify the impact of H4R agonist and antagonist on the expression of E-cadherin and Vimentin after H4R mRNA was interfered by H4R siRNA in MCF-7 cell line.5.The influence of H4R agonist,H4R antagonist and cAMP agonist(forskolin)on the expressions of TGF-?1 mRNA and its protein in MCF-7 cell line were tested by Realtime-PCT and Western blot.Result:1.Immunochemistry staining suggested that breast cancer tissue and the tissue adjacent to breast cancer expressed H4R;fluorescent immune staining suggested that both MCF-7and T47D cell lines express H4R.2.The results of Realtime-PCR and Western blot suggested that H4R mRNA and its protein express in both MCF-7 and T47D cell lines,while T47D cell line had a higher expression level of H4R mRNA(P<0.05)and protein(P<0.05).3.With the tested of Realtime-PCR in MCF-7 cell line,H4R agonist seemed to up-regulate the expression of E-cadherin mRNA(P=0.053),and had the ability to down-regulate the expression of Vimentin mRNA(P<0.01).The pre-conditioning with H4R antagonist had a tendancy of suppress the regulation effect of H4R agonist on E-cadherin mRNA(P=0.099)and Vimentin mRNA(P<0.01).With the tested of fluorescent immune staining in MCF-7 cell line,H4R agonist could up-regulate the expression of E-cadherin and down-regulate the expression of Vimentin.The pre-conditioning with H4R antagonist could suppress the regulation effect of H4R agonist on E-cadherin and Vimentin.4.After the expression of H4R mRNA in MCF-7 cell was down-regulated by H4R siRNA,the expression of E-cadherin mRNA decreased(P<0.05),but the expression of Vimentin mRNA sustained(P>0.05).The pre-conditioning with H4R siRNA could suppress the regulation effect of H4R agonist on E-cadherin mRNA(P<0.05)and Vimentin mRNA(P<0.01).5.In MCF-7 cell line,H4R agonist could down-regulate the expressions of TGF-?1 mRNA(P<0.05)and its protein(P<0.05).And these effects could be significantly suppressed by H4R antagonist(P<0.05).Forskolin could up-regula-te the expressions of TGF-?1 mRNA(P<0.05)and its protein(P<0.05),and these effects were not influenced by H4R agonist.Conclusion:1.Breast cancer tissue and the tissue adjacent to breast cancer,MCF-7 and T47D cell lines expressed H4R.The expressions of H4R were different in breast cancer lines.2.The activation of the H4R had the ability to down-regulate the expression of Vimentin and seemed to up-regulate the expression of E-cadherin in MCF-7 cell line.3.After the expression of H4R mRNA in MCF-7 cell was down-regulated by H4R siRNA,the expression of E-cadherin mRNA decreased,but the express-ion of Vimentin mRNA sustained.4.The activation of the H4R could down-regulate the expression of TGF-?1 and forskolin could up-regulate the expression of TGF-?1 in MCF-7 cell line.5.In breast cancer MCF-7 cell,activate the H4R,possibly via suppressing TGF-?1 signalling pathway,up-regulating E-cadherin and down-regulating Vim-entin to suppress EMT.