Quantum Dots-based Imaging And Quantitative Detection Of JAM-A And Its Impacts On Breast Cancer Prognosis

Breast cancer has been the major threaten to women's health in China.And with the development of living standards,the incidence of breast cancer is still rising.After recieving the combined treatment including surgery,chemotherapy,endocrine therapy and targeted therapy,the prognosis of breast cancer has been greatly improbved.But some patients still developed recurrence or metastasis.Thus,it can be seen that breast cancer is a highly heterogeneous disease.Therefore,it is important find new biomarkers associated closely with the development and progress of breast cancer which could be potential therapeutic target.Tight junction is important to matain the normal structure and function of epithelial cells.Disregulation of tight junction associated proteins play important roles in the development of cancer.Various studies have demonstrated the expression change of several tight junction associated proteins including junction adhension molecule A(JAM-A).JAM-A is an essential member of tight junction.Previous studies found that JAM-A played essential role in inflammation reaction as well as in the development of breast cancer.However,different studies reported controversial roles of JAM-A in breast cancer.Some studies demonstrated that JAM-A was overexpressed in breast cancer and overexpressed JAM-A was associated with poor prognosis of breast cancer.However,other studies found opposite results.Therefore,further studies are needed to clarify the role of JAM-A in breast cancer.Quantum dots(QDs)are new semiconductor nanocrystals.Compared with the conventional dyes,QDs have unique photo-physical properties including size-tunable symmetric emission bands,superior light absorbance,high fluorescent intensity and strong photostability.All of the advantages make QDs promising tools in cancer diagnosis and molecular imaging.In this thesis,based on mining the public database,we investigate the association between the expression of JAM-A and breast cancer with the help of QDs based imaging and analysis system.Part One:Detection of the association between JAM-A expression and breast cancer based on dataminingBackground:Gene sequencing technology has been widely used in life sciences,especially after the occurrence of high-throughput sequencing technology and genechips.All of these technologies have been widely used in the study of tumor and produce enormous data.The researchers usually foucused on some point of the sequencing data which contains many other valueable information.Methods:In this part,we will mine the information about JAM-A expression in breast cancer in two public available databases,the Kaplan-Meier plotter and The Cancer Genome Atlas(TCGA).We detected the expression level of JAM-A in breast cancer and further analyzed the aossciation between JAM-A expression and the characteristics and prognosis of breast cancer.Results:We demonstrated that JAM-A was upregulated in breast cancer and the overexpressed JAM-A was associated with ER negative,HER-2 positive,lymph nodes involvement,later stage and higer tumor grade.JAM-A overexpression was also a negative preditor for breast cancer prognosis(Hazard ratio(HR)=1.35,95%confidence interval:1.20-1.51,p<0.01.)Conclusion:JAM-A overexpression was associated with poor prognosis of breast cancer.Part Two:Quantum dots-based immunofluorescent imaging of JAM-A and identification of prognostic value in breast cancerBackgrounds:Controversial results existed about the role of JAM-A in breast cancer.In part one,we preliminarily analyzed the role of JAM-A in breast cancer based on datamining of public available databases.Methods:In this part,we will detect the expression of JAM-A using quantum dots-based immunofluorescent imaging and identify its prognostic value in breast cancer.186 breast cancer patients receiving sugery in the department of breast and thyroid surgery,Renmin Hospital of Wuhan University between January,2010 and Juauary,2012 was included in the analysis.Information including age,height,weight,past history,tumor size,lymph node,ER status,PR status,HER-2 status,Ki67and prognosis of patients.The expression of JAM-A was detected with quantum dots-based immunoflurescent imaging.Results:We found that JAM-A was overexpressed in breast cancer(breast cancer:43.12 ± 29.56;normal tissue:27.23 ± 8.06,p=0.04).Overexpressed JAM-A was associated with ER negative,HER-2 positive.Furthermore,in both univariate and multivariate Cox regression model,overexpressed JAM-A was associated with poor prognosis of breast cancer(univariate HR=1.014,95%confidence interval:1.007-1.020;multivariate HR=1.013,95%confidence interval:1.005-1.022).Conclusion:JAM-A was overexpressed in ER negative and HER-2 positive breast cancer.Overexpressed JAM-A was associated with poor prognosis of breast cancer.Part Three:Co-imaging of JAM-A,ER and HER-2 and detect the association between JAM-A-ER coexpression and JAM-A-HER-2 coexpression and prognosis of breast cancerBackground:In the first two part,we have clarified the role of JAM-A in breast cancer.We found that JAM-A overexpression was significantly associated with ER negative and HER-2 positive breast cancer.Methods:Therefore,in this section,we will co-image the JAM-A-ER and JAM-A-HER-2 to further clarify the association between JAM-A and ER,HER-2.And further coexpression analysis was also performed.Results:A total of 112 ER positive patients and 57 HER-2 positive patients were included.We detected the expression level of JAM-A,ER and HER-2 quantitatively using quantum dots-based imaging.We found that JAM-A expression was inversely associated with ER expression and positively associated with HER-2 expresssion.And coexpression level of JAM-A and ER had no association with the prognosis of breast cancer.However,coexpression level of JAM-A and HER-2 was positively associated with poor prognosis of breast cancer.Conclusion:JAM-A expression correlated with ER negatively and HER-2 postively.Co-expression of JAM-A and HER-2 was associated with poor prognosis of breast cancer.