The Influence Of Men1and Menin Expression On The Ggressive Of Gastric Cancer

Objective:Tumor suppressor gene Men1encoding protein calls Menin. The article is to study theexpression level of Men1mRNA and Menin in four types of human gastric cancer celllines, gastric epithelial cell lines, the primary tissues of gastric cancer, and correspondingnon-tumorous specimens, then investigates the correlation between the degree of it’sexpression and the invasion or metastasis features, to provide new ideas and targets for themetastasis mechanism research of stomach carcinoma.Methods:(1) RT-PCR and Western blotting were performed to detect the expression level ofMen1mRNA and Menin in four types of Human gastric cancer cell lines (MKN-28,SGC-7901, BGC-823and AGS) and gastric epithelial cell lines (GES-1).Immunofluorescence was used to determine the localization of Menin in the above five celllines.(2) The primary tissues and corresponding non-tumorous specimens were obtainedfrom60patients who were diagnosed with primary gastric cancer and underwentgastrectomy and LN dissection in the Department of Surgery the Fourth Affiliated Hospitalof Soochow University.The RT-PCR was performed to detect the expression level ofMen1mRNA in the specimens for analysising the relationship between the expressionlevel of Men1mRNA and the clinical pathological features. From protein level, Westernblotting and Immunohistochemical method were further used to detect the expression levelof Menin for analysising the relationship between the expression level of of Menin and theclinical pathological features.Results:(1) RT-PCR and Western blotting were used respectively from gene and protein levelto detect the expression level of Men1mRNA and Menin in four types of human gastriccancer cell lines and gastric epithelial cell lines. The results show that Men1mRNA and Menin were generally expressed in four types of human gastric cancer cell lines examinedin this experiment. Expression level with increased of differentiation degree from the AGS,BGC-823, SGC-7901to MKN-28increased; comparing with the former four types celllines, the expression level of Men1mRNA and Menin in GES-1cell lines significantlyincreased (P<0.01). Through the immunofluorescence test, we can see that Menin mainlylocalized in the nucleus, however in the GES-1cell line, Menin was localized not only inthe nucleus, but also in the cytosol and on the membrane.(2) The expression level of Men1mRNA and Menin in the primary tissues of gastriccancer was significantly lower than in corresponding non-tumorous specimens (P <0.05)in60patients suffering from gastric cancer. And, the low expression level of Men1mRNAand Menin associated with the later clinicopathological stages and lymph node metastasis(P <0.05), but no significant correlation (P>0.05) with other clinicopathological factors,such as gender, age, differentiation degree and infiltration depth of gastric cancer patients.Conclusions:Men1mRNA and Menin were expressed in all specimens such as four types of humangastric cancer cell lines, gastric epithelial cell lines, the primary tissues of gastric cancer.and corresponding non-tumorous specimens. But the expression level were different,because of the level of Men1mRNA and Menin in four types of human gastric cancer celllines was significantly lower than in gastric epithelial cell lines,and the level of Men1mRNA and Menin in the primary tissues was significantly lower than in correspondingnon-tumorous specimens. Moreover, the low expression level of Men1mRNA and Meninwas not only associated with the later clinicopathological stages but also lymph nodemetastasis of stomach carcinoma.Our results indicate that Men1and Menin may beinvolved in progression of invasion and metastasis,and may be potential tumor-suppressorfactors.