Expression Of Musashi1 And Numb In Brain Metastases

Objectives: To explore the role of tumor stem cell markers Musashi1(Msi1)and Numb in the development and progression of brain metastases,we detected the expression of Msi1 and Numb in brain metastases,and to further clarify the role of tumor stem cells in the formation of brain metastases,with a view to provides new ideas and directions for the molecular biological mechanism of metastatic tumor development.Methods:1 51 cases samples of brain metastases were collected by surgical resection,29 cases samples of primary tumor and 15 cases samples of normal brain tissue.Parts of the all samples placed in 10% formalin solution;another parts in the fresh state were placed into the-80? low temperature refrigerator.2 The brain metastases and primary tumors were divided into the experimental group,and normal brain tissue group as the control group.Msi1 and Numb protein and mRNA were detected by immunohistochemistry SP method and reverse transcription-polymerase chain reaction(RT-PCR)respectively in different tissues.Each slice was randomly taken 10 high power field,then in the high magnification(×400)according to the intensity score conducted semi-quantitative analysis.The mRNA expression level of the target gene in the electrophoretic was analyzed image by semi-quantitative analysis.Then the OD value of the target gene was measured.The OD value of the target gene was quantified by the OD value of the GAPDH.That is the relative expression level.3 We collect the data of all the patients,then analyze the statistical data by SPSS 21.0.T test was applyed for measurement data;chi-square for qualitative data;Spearman's rank correlation analysis for rank correlation test;Pearson correlation analysis for continuous variable data.All statistical tests were two sided;and P<0.05 was considered to be statistically significant forall tests.Result:1 Expression of Msi1 protein and mRNA in different tissuesImmunohistochemical results: the positive expression rates of Msi1 protein in brain metastases,primary tumors and normal brain tissues were respectively 60.8%(31/51),65.5%(19/29)and 13.3%(2/15).There was no significant difference in the expression of Msi1 protein between brain metastases and primary tumors,which was not statistically significant(P>0.05).The expression of Msi1 protein in brain metastases was significantly higher than that in normal brain tissues,the difference was statistically significant(P<0.05).The expression of Msi1 protein in primary tumors was significantly higher than that in normal brain tissues,the difference was statistically significant(P<0.05).RT-PCR results: the relative expression levels of Msi1 mRNA in brain metastases,primary tumors and normal brain tissues were respectively0.78±0.50,0.60±0.36 and 0.38±0.29.There was no significant difference in the expression of Msi1 mRNA between brain metastases and primary tumors(P>0.05).The expression of Msi1 mRNA in brain metastases was significantly higher than that in normal brain tissues,the difference was statistically significant(P<0.05).The expression of Msi1 mRNA in primary tumors was significantly higher than that in normal brain tissues,the difference was statistically significant(P<0.05).2 Expression of Numb protein and mRNA in different tissuesImmunohistochemical results: the positive expression rates of Numb protein in brain metastases,primary tumors and normal brain tissues were respectively 33.3%(17/51),31.0%(9/29)and 73.3%(11/15).There was no significant difference in the expression of Numb protein between brain metastases and primary tumors,which was not statistically significant(P>0.05).The expression of Numb protein in brain metastases was significantly lower than that in normal brain tissues,the difference was statistically significant(P<0.05).The expression of Numb protein in primarytumors was significantly lower than that in normal brain tissues,the difference was statistically significant(P<0.05).RT-PCR results: the relative expression levels of Numb mRNA in brain metastases,primary tumors and normal brain tissues were respectively0.34±0.21,0.47±0.31 and 2.42±1.82.There was no significant difference in the expression of Numb mRNA between brain metastases and primary tumors(P>0.05).The expression of Numb mRNA in brain metastases was significantly lower than that in normal brain tissues,the difference was statistically significant(P<0.05).The expression of Numb mRNA in primary tumors was significantly lower than that in normal brain tissues,the difference was statistically significant(P<0.05).3 The relationship of the expressions of Msi1 and Numb in brain metastasesThe expression of Msi1 protein was negatively correlated with Numb protein(r=-0.258,P < 0.05)in brain metastases by Spearman correlation analysis.There was a negative linear correlation between Msi1 and Numb mRNA expression(r=-0.345,P < 0.05)in brain metastases by Pearson correlation analysis.4 The analysis between expression of Msi1 and Numb in brain metastases and clinicopathological factorsThe expression of Msi1 and Numb in brain metastases was not correlated with gender,age and tissue origin(P>0.05).Conclusion:1 Msi1 protein and mRNA were highly expressed in brain metastases and primary tumors.Numb protein and mRNA were lowly expressed in brain metastases and primary tumors,indicating that these two abnormal expresses played an important role in the formation of brain metastases.2 Msi1 and Numb were negatively correlated in brain metastases and primary tumors.It was speculated that Msi1 and Numb had a regulatory mechanism in the development of brain metastases.3 Tumor stem cell marker Msi1 was highly expressed in brain metastasesand primary tumors,suggesting that tumor stem cells may be present in brain metastases.4 The expression of Msi1 and Numb in brain metastases was not associated with gender,age and tissue origin.