To Explore The Target Protein Of HGC-27 Aptamer In Human Gastric Cancer Cells With High Metastasis

Part ?:Detection and clinical analysis of nucleic acid aptamer lw-25 in gastric cancer tissue sections[Background] In recent years,with the in-depth study of nucleic acid aptamers,more and more tumor cell aptamers have been discovered,these aptamers can specifically identify their corresponding tumor cells.However,most of these aptamers can only bind to their target cells in a specific laboratory environment and have not been truly applied to clinical research.The aim of this study was to use the selected aptamer LW-25,which can specifically identify gastric cancer cells with high metastasis HGC-27 but not gastric cancer cells without metastasis to study its binding ability with gastric cancer biopsy and to conduct clinical analysis.[Obiective] LW-25,an aptamer of HGC-27 in gastric cancer cells,was synthesized to explore its binding ability with clinicopathological sections and to conduct relevant clinical analysis.[Methods]Synthesis of LW-25,a nucleic acid aptamer of HGC-27 in gastric cancer cells.Then it was modified with fluorescence.Finally,the aptamer LW-25 was incubated in gastric cancer tissue sections,the combined results were observed with confocal microscopyand to conduct relevant clinical analysis.[Results]1.The recognition rate of nucleic acid aptamer LW-25 in metastatic gastric cancer tissue sections was much higher than that in gastric cancer tissue sections without lymph node metastasis.2.When the aptamer LW-25 was incubated with gastric cancer sections with lymph node metastasis,patients with negative staining(false negative)had higher histopathological differentiation and lower TNM staging than patients with true positive.3.When the aptamer LW-25 was incubated with gastric cancer sections without lymph node metastasis,the histopathological differentiation degree of the patients with positive staining(false positive)was worse than that of the patients with true negative,the TNM stage was higher.[Conlusions]1.The aptamer LW-25 can specifically identify the pathological sections of gastric cancer with lymph node metastasis.2.The accuracy of aptamer LW-25 in identifying gastric cancer sections with lymph node metastasis may be related to the degree of histopathological differentiation of gastric cancer tissues and TNM stage.3.The aptamer LW-25 has the potential to predict lymph node metastasis in gastric cancer.Part ?:Target identification of Aptamer of HGC-27 cells with high metastatic potential[Background] Gastric cancer is one of the four most common malignancies in the world.The incidence of gastric cancer is increasing year by year.However,the early symptoms of most patients with gastric cancer are not obvious,as a result,the majority of patients with gastric cancer have cancer metastasis at the time of visit,which undoubtedly delays the best time for cancer treatment.Until now,monitoring early metastasis of gastric cancer has been a medical challenge.Therefore,if we can identify the tumor markers of highly metastatic gastric cancer cells,it will bring great prospects for early monitoring of gastric cancer metastasis and understanding how gastric cancer progresses.Aptamers have become the focus of clinical research recently in the diagnosis and treatment of clinical tumors,the purpose of this study was to identify the specific binding tumor marker of LW-25 which is an aptamer for highly metastatic gastric cancer cells.[Obiective] Cell-SELEX technique was used to screen the aptamer LW-25,which can specifically recognize HGC-27 cells,and to explore the target protein binding to HGC-27 cells.[Methods] Synthetic aptamer LW-25,which can specifically identify gastric cancer cells with high metastasis but not gastric cancer cells without metastasis.First,using the trypsin method to digest cells to identify the type of protein that the aptamer binds to,then the protein is extracted from the gastric cancer cells by lysing the cells.HGC-27 binding proteins of gastric cancer cells with high metastasis were isolated by aptamer-mediated affinity enrichment,then proteins were isolated by electrophoresis,Find out the difference bands which are the potential target proteins.Finally,the separated bands were sent to mass spectrometry to determine the potential target proteins by analyzing the mass spectrometry results.[Results]1.The binding site of aptamer LW-25 to HGC-27 cells is protein.2.The difference bands were found by SDS-PAGE,and the NONO protein was the most obvious one by mass spectrum analysis.[Conlusions] In this study,the aptamer that can specifically identify HGC27 in gastric cancer cells with high metastasis was successfully screened by cell-SELEX technology.First,the target type was identified as protein,then it was further analyzed that NONO protein was a potential target protein of LW-25 and was likely to be an important protein causing gastric cancer metastasis.It will bring a great prospect for early monitoring of gastric cancer metastasis and exploring the mechanism of gastric cancer metastasis.