Visual Analysis Of Single Cell Correlation Between EMT And Drug Sensitivity Of Tumor Cells Based On Microfluidic Chip

The process by which epithelial cells are transformed into mesenchymal phenotype cells under specific physiological or pathological conditions is called "epithelial mesenchymal transformation"(EMT).It not only plays an important role in embryonic development and stem cell behavior,but also plays an important role in the occurrence and development of tumor metastasis.After the occurrence of EMT in tumor cells,the cytoskeleton proteins are also changed,and the expression of EpCAM and other proteins of epithelial adhesion molecules is absent,which reduces the adhesion between cells and increases the intercellular space.In the mean time,the motor ability of the cells is enhanced,and the cells are capable of invasion and metastasis to a distance.Many studies have shown that tumor cells acquire a high degree of invasiveness after EMT,at the same time,many genes involved in drug metabolism are activated,that changed the sensitivity of tumor cells to chemotherapy drugs.This indicated that EMT of tumor cells was significantly correlated with drug resistance.Therefore,the study of tumor cell EMT plays an important role in determining the drug resistance of tumor cells.CTCs is a new biomarker for liquid biopsy,and its detection and analysis can be used as an effective means for early prevention of tumor,drug sensitivity test and tumor recurrence monitoring.However,the number of CTCs is rare and it is difficult to analyze the cell population by conventional methods.In addition,CTCs are also heterogeneous,and EMT is an important aspect of CTCs phenotypic heterogeneity.EMT is dynamic and reversible,and accompanies every stage of clinical treatment.Therefore,the study on the correlation between EMT level and drug sensitivity of single circulating tumor cells can provide a reliable program for personalized clinical diagnosis and treatment.To sum up the above problems,we established a single-cell,high-throughput analysis method based on microfluidic chip.Fluorescence imaging was performed to study the EMT degree and drug sensitivity of CTCs.The research content of this paper is as follows:The first chapter is the introduction,which introduces the characteristics of CTC,summarizes the enrichment,sorting and analysis of CTC,briefly describes the various schemes of CTC sorting,and the research progress in the analysis and detection of CTC from the perspective of genomics,proteomics and phenotype.The second chapter is the single-cell visualization analysis and research on the correlation between EMT degree and drug sensitivity of tumor cells based on microfluidic microarray.First,we constructed a Christmas tree structure chip with a single cell capture microchamber,and successfully completed the single-cell capture of rare cells and cell culture on the chip.Moreover,the concentration gradient of the solution was established on the chip to realize the process of cell capture,stimulation and labeling,and the cell phenotype and apoptosis were analyzed by real-time online tricolor imaging.Subsequently,CTCs in blood samples were sorted by combining with the sorting chip designed by our research group,and the EMT degree and drug sensitivity of single CTCs were visualized and analyzed.