The Effect Of Tenascin-C On Anchorage-Independent Proliferation In Gastric Cancer SGC7901 Cells

Background:Gastric cancer(GC)is a common tumor of the digestive system,which has a low early diagnosis rate and poor prognosis.Therefore,it is increasingly important to search for possible markers for early diagnosis and targeted therapy.Tenascin C(TNC)is an extracellular glycoprotein that is produced in the processes of cell proliferation,migration and organ formation.It has been widely studied as a potential biomarker for different cancers.However,so far,the role and function of TNC in GC and gastric cancer cells which were cultured in vitro are still unclear.This experiment will carry out preliminary research for this purpose.TNC is currently known to interact with epidermal growth factor receptors and integrins to regulate the activity of many intracellular signaling molecules,such as Focal Adhesion Kinase(FAK),extracellular regulated protein kinases(ERK)and protein kinase B(Akt),thereby playing multiple roles in cell activities.This experiment founds that TNC is highly expressed in GC tissues and gastric cancer cell lines,and TNC has an important effect on the anchorage-independent growth of gastric cancer SGC7901 cells.ITGB7 may also be involved in this process.Objective: The main research content of this experiment1.Detection of TNC expression in gastric cancer tissue samples and gastric cancer cell lines.2.The effect of knocking out TNC on the growth of gastric cancer cells.3.Looking for growth pathways that may be participated in this effect.Methods: 1.The expression of TNC in gastric cancer pathological tissue samples and normal tissue samples around the cancer were detected by immunohistochemistry.Western blotting was used to detect the expression of TNC in normal gastric mucosa epithelial cell lines and different gastric cancer cell lines.2.Knock out the TNC gene in gastric cancer SGC7901 cells,then observe and analyze the formation of cell colonies by soft agar colony formation experiments.3.After knockout of TNC,using reverse transcription polymerase chain reaction(RT-PCR)and Western blotting to disclose the expression of integrin subunits in gastric cancer SGC7901 cells.4.TNC salvage experiment was used to observe anchor growth of SGC7901 cells with TNC knockout.5.Use immunoprecipitation experiments and GST-pull down experiments to explore whether there is an interaction between integrin and TNC.Results:This experiment shows that TNC is highly expressed in gastric cancer tissues,and also has a higher expression level in SGC7901 cells.Through repeated experiments,it was found that the anchorage-independent growth ability of gastric cancer SGC7901 cells was disappeared after TNC knockout,and the phosphorylation levels of the proteins AKT,JNK,and ERK,which are common in the cell proliferation pathway also changed.In addition,the expression of integrin ITGB7 in TNC-deficient gastric cancer cells decreased significantly,while the expression of the epidermal growth factor receptor family did not change at the detection level.The protein interaction experimentresults show that there is a direct interaction between ITGB7 and TNC.The salvage experiment after TNC knockout confirmed the important effect of TNC on anchorage independent growth of gastric cancer SGC7901 cells.This experiment shows that TNC can mediate anchored independent growth of gastric cancer cells and play an indispensable role in it.The change in the expression of ITGB7 after TNC loss suggests that it may play a relevant role in this process,and the specific mechanism still needs further research.Conclusion: TNC is highly expressed in gastric cancer tissues and gastric cancer cell lines.In gastric cancer SGC7901 cells,TNC can mediate its anchorage independent growth,due to an interaction between ITGB7 and TNC,so ITGB7 may also participate in this process.The high expression of TNC in gastric cancer tissues and its effect on anchoring independent growth of SGC7901 cells can provide new possibilities for finding new markers for gastric cancer diagnosis and targeted therapy.