The Biological Characteristics And Molecular Mechanism Of CathepsinZ And CD97 In Gastric Cancer Cell Lines And Clinic

Objective:The aim of this study is to explore the effects and action mechanism of CTSZ and CD97 in gastric cancer cell invasion based on the research of the biological characteristics of CathepsinZ and CD97 in gastric cancer cell lines and its molecular mechanism. At the same time, through the research of CTSZ expression and clinical significance of gastric cancer tissues in patients, to discuss its role in the gastric cancer occurrence, development process, and further understand its value in clinical, provide theoretical basis for the early diagnosis of gastric cancer and immune therapy.Methods:we firstly test the lever of CTSZ gene and total protein in gastric cancer cell line based on the research of PCR and western blot experiment. After that we build CTSZ expression plasmid and siRNA interference CTSZ plasmid using pcDNA3.1 and pGCsilencer respectively. restructuring CTSZ over expression and CTSZ RNAi cloning by transfection gastric cancer cell, and through the confocal microscope and flow cytometry as well as scratch assay, the effects of the gastric cancer cell biology behavior was observed. In addition, further research cytoskeletal signaling pathways, study the mechanism of action of CTSZ and CD97 in gastric cancer cells invasive. Application of immunohistochemical to stain normal, adjacent and cancerous tissue in patients with gastric cancer as well as detect CTSZ expression level. Observing gastric cancer tissue CTSZ expression level in different TNM staging of gastric cancer at the same time.Results:1 There are different levels of CTSZ gene and total protein expression in different gastric cancer cell lines 2 CTSZ located at the same distribution area with lysosome in gastric cancer cells.3 compared to untransfection group, the expression plasmid pcDNA3.1-CTSZ transfected gastric cancer cell, cytoskeletal present to spread around the shape change, cell cycle shortened, aggressive and migration ability. Interference cloning pGCsilencer-CTSZ transfection gastric cancer cell, protein and cycle related protein expression levels decline involved in migration, aggressive and migration ability.4 transcription factor SP1 in pcDNA3.1-CD97 group increased compared to the expression in pcDNA3.1 CD97-JNK signaling pathway plus SP600125 inhibitor group.5 immune co-precipitation (chips) to detect SP1 transcription factor acting on CTSZ 1000 bp upstream transcription start site, and dual luciferase reporter gene detected CD97 also applies to CTSZ consistent 1000 bp upstream transcription start site.6 western blot analysis found that compared to untransfection group, pGCsilencer-SP1 and pcDNA3.1-SP1 transfection gastric cancer cell, CTSZ expression corresponding drop and rise, While elevated CTSZ expression was oberserved in pcDNA3.1-CD97 transfection gastric cancer cells. The total CTSZ expression declined in PcDNA3.1-CD97 and pGCsilencer-SP1 co-transfection group of gastric cancer cells. Normal, adjacent and carcinoma tissue, compared each other, the difference of CTSZ expression was statistically significant (P<0.05), the difference of CTSZ expression level in the TNM staging of gastric cancer had statistics meaning (P<0.05).Conclusion:CD97 expression in gastric cancer cells has the close relation to tumor invasive, this phenomenon has been widely accepted, but the mechanism of the malignant tumor CD97 in the study is still in its infancy. This study for the first time discovered CTSZ expression intensity and gastric cancer cell invasion and migration ability through CTSZ overexpression of cloning and disturbance of siRNA-CTSZ builds, the CTSZ role in gastric cancer has made a preliminary exploration, were positively correlated. Although partial results still need further animal experiment, but this study through the preliminary discussion in CTSZ gene in gastric cancer cell, reveals the characteristics of CTSZ gene, heralded the CTSZ is suitable for the emerging markers for gastric cancer and gastric cancer gene therapy targets for the development direction. Also, it has a good application prospect. We the firstly reveals the mechanism of CD97 promote gastric cancer cell invasion by JNK signaling pathway and SP1 prompted CTSZ gene high expression of transcription factors, resulting in increased gastric cancer cell invasive, and laid a more solid theoretical and experimental basis for further gene therapy and gastric cancer research. CTSZ expression level is closely related to the occurrence of gastric cancer development, at the same time can be a rough evaluation of gastric cancer staging, and provides a theoretical basis for CTSZ as a target immunotherapy to gastric cancer.