Relations Of Seminoma Associated Genes Expression To Stat3 Signal Pathway And Their Implication

OBJECTIVE:In order to reveal the molecular mechanism by which seminoma occurs,study the relationship of the changes in tumor molecular pathology to pathological morphology and clinical biological behave,and provide the academic evidence for the clinical therapy targeted to STAT3 in seminoma,the inducing and stimulating effects of the signal transduction was assessed by determining Stat3 protein expression in seminoma;the hyperplasia-stimulation effects of the JAK/STAT3 signal transducer pathway in this tumor was investigated by measuring VEGF and C-myc,and the anti-apoptosis effects of STAT3/Bcl-xl in development of seminoma were explored by detecting HIWI and Bcl-xl.In order to provide the molecular biologic evidence for the early identified diagnosis and treatment of seminoma,the alteration of oncogenes and anti-oncogenes in the seminoma canceration was studied by observing gene expression of Oct4, PLAP,VEGF,and p53.In order to accumulate experimental evidence for endocrine therapy for seminoma,the relationship between hormone receptor and tumor occurring was investigated by determining seminoma hormone receptors,such as AR,ER-αand PR.METHODS:Paraffin specimen of seminoma and normal human testis tissue were collected. IHC(immunohistochemistry) were used to detect the protein of Star3,VEGF,C-myc,Bcl-xl,p53, Oct4,PLAP,AR,ER-αand PR;ISH(in situ hybridization) were used to observe the mRNA transcription of HIWI and AR.Saturated hydroxybenzene chloroform were applied to gain the DNA from 11 paraffin tissue and PCR-SSCP(ploy chain reaction single-strand conformation polymorphism) were to examine the deletion and mutation of p53 in seminoma.RESULTS:The expression of STAT3 protein was in nucleus or cytoplasm,VEGF,C-myc and Bcl-xl protein was in cytoplasm in 38 seminoma.The positive expression rate of STAT3,VEGF, C-myc and Bcl-xl was 76.3%,71.1%,84.2%,71.1%,and comparing normal testis tissue they all had different significance in statistics(p＜0.01),and these genes all had relevance with the TNM clinical stage in seminoma.The expression of HIWI mRNA was in nucleus and partly in cytoplasm in 38 seminoma. The positive expression rate of HIWI mRNA was 68.4%,comparing normal testis tissue it had different significance in statistics(p＜0.05).But it was none of the business of the TNM clinical stage.There was positive relevance between STAT3 and VEGF(p＜0.01),STAT3 and C-myc (p＜0.05),STAT3 and Bcl-xl(p＜0.01),STAT3 and HIWI(p＜0.01),STAT3 and P53(p＜0.01), HIWI and BCL-xl(p＜0.01),C-myc and VEGF(p＜0.05).The expression of Oct4 protein was in nucleus and the positive expression rate in 38 seminoma was 100%,but in normal testicle tissue were zero.The expression of PLAP protein was at cell membrane.The positive expression rate of PLAP in seminoma were 89.47%,but in normal testicle tissue were zero too.However,on the base of the observation of microscope, there was little or no background staining in the all slices of Oct4,and there was a high level of background staining artifact in many slices of PLAP.The positive expression rate of VEGF in seminoma clinical stageⅠ,Ⅱ,Ⅲwere 33.33%, 90.91%,100%.There were different significance of VEGF between StageⅠand stageⅡ,stageⅠand stageⅢ(p＜0.01),there were no different significance of VEGF between StageⅡand stageⅢ(p＞0.05);10 normal testicle tissue samples,2 samples were weakly positive,8 samples were negative.The positive expression rate of p53 in seminoma clinical stageⅠ,Ⅱ,Ⅲwere 93.33%,54.55%,50%.There were different significance of p53 between StageⅠand stageⅡ, stageⅠand stageⅢ(p＜0.05),there were no different significance of p53 between StageⅡand stageⅢp＞0.05);10 normal testicle tissue samples were all negative.There were p53 mutations in seminoma,the mutation rate was 45.45%.By the research we confirm that there were expression of AR mRNA and AR protein in the cytoplasm of some seminoma.When the expression of AR mRNA is positive,comparing normal testis,it had different significance in statistics(p＜0.05),it suggest that when the primordial germ cell malignant,the expression of AR could be descend.CONCLUSIONS:1.The JAK/STAT3 signal transducer pathway can increase the expression of C-myc and cause the malignancy hyperplasy of germinal cell,which provocating seminoma. 2.The JAK/STAT3 signal transducer pathway can activate the expression of VEGF,and impulse the development of seminoma.3.In seminoma,the gene HIWI can activate the STAT3/Bcl-xl signal transducer pathway,give tumor cell the ability of self-renewal and anti-apoptosis.4.Oct4 is all positive in seminoma,it is an excellent marker gene of seminoma diagnostic.It is more sensitive than PLAP.5.p53 has the genes abnormality with the genesis and development of seminoma.6.Seminoma can be distinguish by the expression of AR protein to positive and negative.The ER-αand AR protein are both negative expression in seminoma.