Study On The Mechanism Of DDX5 Regulating The Growth And Function Of Stomach Neoplasm Cells Based On DEG Of Different Growth Patterns Stomach Neoplasm

Objective In order to study the molecular mechanism of stomach neoplasm with different growth patterns,high-throughput transcriptomics sequencing was performed on the two different growth modes of gastric cancer cell lines screened out by our group and found a key differential gene,DDX5.This study detected the expression level of DDX5 in stomach neoplasm tissues,normal tissues adjacent to cancer and related gastric cancer cell lines,combined with the relevant clinical pathological data and clinical stage of patients to explore the correlation trend of DDX5 expression level and clinical pathological characteristics.At the same time,we studied the regulatory mechanism of DDX5 on the biological function of gastric cancer cell lines,and sought potential new targets for stomach neoplasm gene therapy,providing a new basis for stomach neoplasm screening and patient prognosis.Methods1.RNA was extracted from two different growth patterns GC cell lines for high-throughput transcriptome sequencing;2.Differential expression genes of two types of GC were analyzed by using biological informatic methods;3.The expression level of DDX5 in 80 cases of GC tissue and matched GC adjacent were detected by immunohistochemistry staining;4.Taken corresponding clinical characteristic into consideration,the correlation between the expression level of DDX5 in stomach neoplasm and the clinical and the pathological characteristics of stomach neoplasm was analyzed;5.The plasmids of knockdown of DDX5 were transfected into MGC803 and SGC 7901 GC cell lines by lentiviral expression plasmid;6.The effects of DDX5 on proliferation,migration were monitored by colony formation assay and Transwell chamber assay.Results1.High-throughput sequencing consequences demonstrated that there are amounts of differential expression genes(DEGs)in different growth patterns GC cell lines,and the fold change of DEGs was larger than 2 times;2.The expression of DDX5 in invasive GC cell lines is 4 times more than that in expansive GC cell lines;3.The expression of DDX5 significantly up-regulated in 59 cases(59/80,73.8%)GC tissues,compared with normal adjacent tissues,was supported by IHC staining;4.The expression level of DDX5 in GC was correlated obviously with the degree of differentiation(P=0.042)and location of tumor(P=0.011)and stomach neoplasm with different growth patterns(P=0.038),though was independent of the patient’s gender,age,tumor stage and lymph node metastasis(P > 0.05);5.The expression of DDX5 in MGC803 and SGC7901 GC cell lines,after transfected by knockdown DDX5 lentiviral expression plasmids,was apparently down-regulated compared with that in negative control group;6.The ability of proliferation and colony formation was significantly inhibited in MGC803 and SGC7901-DDX5 knockdown cell lines compared with the negative control group,demonstrated by colony formation assays;7.Transwell chamber experiments revealed the capability of migration apparently was suppressed in DDX5-down-regulated GC cell lines,comparing with the negative control group.Conclusion1.There are a mass of aberrantly expressed encoding genes in different growth patterns of GC cell lines;2.The expression level of DDX5 is notably increased in invasive GC cell lines,moreover,the expression level of DDX5 in Ming’s infiltrating stomach neoplasm is higher than that of expansive stomach neoplasm.3.The expression level of DDX5 was correlative to location(P=0.042)and differentiation(P=0.011)of tumor and stomach neoplasm with different growth patterns(P=0.038),but not related to gender,age,distant metastasis,lymph node metastasis and TNM staging;4.After knockdown of DDX5 with lentiviral plasmids,the proliferation and migration of gastric cancer cells were significantly inhibited;5.The expression level of DDX5 was closely related to the degree of differentiation in GC by IHC staining;Taken theses together,DDX5 is likely to paly a crucial role of oncogene in the development of GC,indicating that DDX5 may be a potential target for GC treatment.Moreover,the expression level of DDX5 is correlated to the GC clinical stage,which probably will be a prognostic marker of GC.