The Effect Of Helicobacter Pylori Caga On The Expression Of CIP2A In Gastric Cancer Cells And The Differentially Expressed Of Microrna Between Before Metastasis Tumor Tissues Or After Metastasis Ones

ObjectiveH.pylori CagA upregulates the expression of protein CIP2 A,an important original carcinomas.The cell signaling moleculers that involved in the regulation will be studied,in order to further research the molecular mechanism that CagA increased CIP2 A expression,and to understand its role in gastric cancer.The mechanism of gastric cancer metastasis is not fully understood.This research studied the differential expression of microRNA between gastric cancer metastasis before and after,and screened the gastric cancer metastasis related microRNA,to further study on mechanism and lay theoretical basis for targeted therapy of gastric cancer metastasis.MethodsAGS cell and GES-1 cell were cultured,B-Raf was inhibited by signal inhibitors GDC-0879,JNK2 was inhibited by signal inhibitors SP600125.JNK2 and B-Raf were interfered by interference RNA,CagA positive plasmid WT-cagA and negative control pcDNA3.1 were transfected,CIP2 A expression were detected by Western blot,cell proliferation ability were tested by cell clone formation,cell migration ability were tested by cell migration.Gastric cancer cells BGC-823 were cultured,the cells were collected and were injected into back subcutaneous of nude mice,and the tumor formed,then the tumor were transfered nude mice stomach,and it continue to passage.The tumor tissue of gastric cancer metastasis before and after were obtained,extraction of RNA respectively,Small RNA chip was used to analyze the different expression the microRNA.ResultsAGS and GES-1 cells were transfected with CagA plasmid,CIP2 A was upregulated.These cells were treated by inhibitors and the corresponding signal interference RNA in cells,then transfected with CagA plasmid,CIP2 A expression decreased,cell proliferation reduced,cell migration ability reduced too.Gene chip with 3552 genes were used,849 genes expression changes,and there are 14 microRNA related to the gastric cancer transfer,they changed greater than 4 times,including raised 11 microRNA and downregulated 3 microRNA.ConclusionHelicobacter pylori CagA upregulated CIP2 A through the B-Raf and JNK2.Helicobacter pylori CagA enter cells through the Sac→ CagA-y-p→ Shp-2→ Rap-1→ B-Raf→ Erk-1→ P38→ JNK way to influence CIP2 A expression and then affect cell clone formation ability and cell migration ability.This study prepared successfully the animal model of nude mouse stomach cancer metastasis,and the differentially expressed microRNA were screened out.There were 14 differentially expressed microRNA related to metastasis of gastric cancer,their change fold is more than 4.There are 11 expressed up-regulated microRNA and 3 down regulated ones.