Research On The Activity Of CDH1 Promoter In 4T1 Cell By Constructing The Dual Fluorescent Reporter Genes Vectors

Breast cancer is the most frequent cancer in women, the mortality of breast cancer increases year by year. The main reason of breast cancer death is the metastases of cancer cells, thus the study of breast cancer metastasis is particularly important. Currently, EMT (Epithelial to mesenchymal transition) theory is approved for breast cancer metastasis, and the important marker of EMT is E-cadherin. E-cadherin is a protein closely related to invasion and metastases in breast cancer, with its lower expression or the loss of genes as a sign of EMT. However, clinically, high expression of CDH1 is characterized in many metastases breast cancer, and its role in the development and metastasis of breast cancer need to be further in-depth discussed. In order to study the biological behavior and foundation of E-cadherin (CDH1) positive and negative cells, we use 4t1 cells as the model, which is the metastatic breast cancer cells of mice and high express E-cadherin。We construct double fluorescent reporter vector driven by CDH1 promoter, sort out E-cadherin (CDH1) positive and negative cells by flow cytometry, observe the different morphological characteristics of the two kinds of cells in vitro. The result show that the double fluorescent reporter vector driven by CDH1 promoter is construct succeed, the CDH1 positive cells and the CDH1 negative cells in vitro showed obvious difference, when the CDH1 negative cells grow up to a certain degree of polymerization, the cell group of the middle area start to float and escape, however, the CDH1 positive cell did not display this phenomenon,so the lack of E-cadherin is just the need but not sufficient condition for the EMT and metastasize. The analysis Of CDH1 transcription start site upstream 1000 bp find the binding sites of p53 which have a positive regulation effect on increasing E-cadherin expression, and p53 is high expressing in glioma, that may be the reason of high E-cadherin expression in brain tumor metastased from breast cancer.