Expression And Correlation Of GPSM2 And BMI1 In Pancreatic Cancer

OBJECTIVE: Recently,a large number of studies have shown that the change of the expression of RNA itself has an important impact on the occurrence and development of pancreatic cancer.Therefore,it is very important to find the expression of genes related to pancreatic cancer and find the tumor markers of pancreatic cancer.Before this study,our team has found that GPSM2 plays a role in promoting the occurrence and development of pancreatic cancer,while Bmi1 gene promotes the proliferation and differentiation of pancreatic cancer stem cells.We hypothesized that there may be a co-expression relationship between GPSM2 and Bmi1 gene.Therefore,this study validates the correlation between GPSM2 and pancreatic cancer through the analysis of GEO(Gene Expression Omnibus)database and TCGA database(The Cancer Genome Atlas),and finds out the correlation between GPSM2 and Bmi1,and validates the relationship between GPSM2 and Bmi1.Therefore,it lays a theoretical foundation for further study of the role of GPSM2 and Bmi1 in the occurrence and development of pancreatic cancer and for searching for tumor markers of pancreatic cancer.Methods: By downloading the relevant information in the GEO database,using R language and other methods,the differential gene analysis of the relevant information in GEO database was carried out to observe the expression of GPSM2 in pancreatic cancer patients.Meanwhile,the related data of survival time of pancreatic cancer patients were downloaded in TCGA database,and the survival prognosis of patients with high expression of GPSM2 gene was analyzed to find out the influence of GPSM2 on survival prognosis of pancreatic cancer patients.? The difference of expression of GPSM2 in normal patients and cancer patients was studied by online database GEPIA(http://gepia.cancer-pku.cn/),and the differential expression of GPSM2 in cancer tissues and adjacent tissues was analyzed.The relationship between GPSM2 and Bmi1 was also analyzed.Then,the protein interaction network of GPSM2 related genes was constructed,and the functions were analyzed by DIVAD and Kyoto Genome Spectrum(KEGG).Construct stable cell lines with low and high expression of GPSM2,and observe cell growth and morphological changes at any time.Western blot was used to detect the expression of GPSM2 and Bmi1 in pancreatic cancer cells.Real-time quantitative reverse transcription polymerase chain reaction(RT-PCR)was used to detect the expression of GPSM2 and Bmi1 in pancreatic cancer cells.RESULTS: A total of 1044 differentially expressed genes were screened from GSE46234 data set in GEO database,of which 298 were overexpressed and 746 were underexpressed.It was found that GPSM2 was overexpressed in pancreatic cancer patients.After the survival analysis of pancreatic cancer patients in TCGA database,it was found that the survival time of patients with high expression of GPSM2 was lower than that of patients with low expression of GPSM2.The expression of GPSM2 in cancer tissues and adjacent tissues was higher than that in adjacent tissues,and higher in pathological stage IV.The protein network map of GPSM2 was constructed and enriched.It was found that GPSM2 had obvious enrichment in the cancer-promoting pathway.The co-expression relationship between GPSM2 and Bmi1 was found by using online database.The results of PCR showed that the stable transformants with high expression of GPSM2 and low expression of GPSM2 were successfully constructed;in the high expression group of GPSM2,the expression of related genes of GPSM2 and Bmi1 increased;and in the low expression group of GPSM2,the expression of related genes of GPSM2 and Bmi1 decreased.Western blot results showed that the expression of related proteins of GPSM2 and Bmi1 increased in the high expression group of GPSM2,while the expression of related proteins of GPSM2 and Bmi1 decreased in the low expression group of GPSM2.CONCLUSION: GPSM2 is correlated with survival and prognosis of pancreatic cancer patients.The expression of GPSM2 in cancer tissues is higher than that in adjacent tissues,and the worse the pathological stages,the higher the expression of GPSM2.The positive correlation between GPSM2 and Bmi1 has also been proved by experiments.In conclusion,it can be inferred that GPSM2 and Bmi1 may promote the occurrence and development of pancreatic cancer,and they may be potential markers of pancreatic cancer.