Effects Of RSK4 On Proliferation,Apoptosis And Invasion Of Human Gastric Cancer Cells BGC803 And HGC27

BackgroundGastric cancer is the most common malignant tumor with high mortality in the gastrointestinal.The widespread development of early screening and the increasing emphasis on health have led to a decline in the incidence of gastric cancer over the past country.In recent years,the early diagnosis rate and early cure rate in our country’s gastric cancer have increased.The incidence of gastric cancer,which is also due to the improvement of sanitary conditions and medical conditions in China,has decreased.However,the mortality rate of progressive and advanced gastric cancer has not gradually improved,and metastasis is the main reason for the increase in recurrence rate and mortality of this invasive disease.At present,radical surgical resection is an important treatment for this disease,and the latest evidence in the guidelines indicates that neoadjuvant radiotherapy and chemotherapy plus surgical treatment can improve the cure rate of gastric cancer surgery,reduce tumor metastasis and recurrence rate,and promote prognosis.However,the mortality of advanced and advanced gastric cancer has not improved.Metastasis is the main reason for the recurrence rate and mortality increase of this aggressive disease.In recent years,targeted therapy for gastric cancer has resulted in better tumor eradication and longer survival for advanced and advanced gastric cancer.At present,research on targeted therapy is also a hot topic in many studies.Multiple studies have shown that P90 ribosomal protein S6 kinase 4(RSK4)protein is expressed in a variety of malignant tumors,and has a positive effect on inhibiting tumors and determining tumor efficacy.there is a lack of research on the expression of RSK4 gene in gastric cancer cells and its effects on cell proliferation,apoptosis,migration and invasion.Multiple studies have shown that P90 ribosomal protein S6 kinase 4(RSK4)has tumor suppressive effects in individual malignant tumors.Research purposesTo investigate the expression of P90 ribosomal protein S6 kinase 4(RSK4)in human gastric cancer cell line(GCCL)and the effect of RSK4 on GCCL’s apoptosis,proliferation,invasion and biological effects in solid tumors.SignificanceThe experimental basis for studying the mechanism of detecting the role of RSK4 in gastric cancer cells is provided.MethodsThrough experiments,gastric cancer cell lines with high expression of P90 ribosomal protein S6 kinase 4(RSK4)were screened.LipofectamineTM 2000 transfection reagent carrying the siRSK4 gene was used to transfect the selected cell lines to establish a gastric cancer cell line with RSK4 knockout gene.qRT-PCR and Western blot(WB)analysis which used to be confirmed the silencing of RSK4 gene expression in the HGC-27 cell line.Use the methyl thiazoletetrazole(MTT)to detect the proliferation of gastric cancer cells after transfection.Flow cytometry was used to detect the cycle and apoptosis of the cells after transfection.And the difference in cell apoptosis was tested under the anti-tumor environment of chemotherapeutic drugs.And Scratch experiments and Transwell experiments were used to detect the cell how to deal with invasion and migration.At last,tumor-bearing mice were used to study the effect of RSK4 on subcutaneous tumor formationResearch resultThrough the expression of RSK4 in gastric cancer cells was evaluated using RT-qPCR and Western blot analysis.From the four types of cells of gastric cell line(Ges-1)and gastric cancer cell lines(SGC-7901,BGC-803,HGC-27),two gastric cancer cell lines,BGC-803 and HGC-27 with high RSK4 expression,were screened.The HGC-27 and BGC-803 cell lines were transfected with LipofectamineTM 2000 transfection reagent carrying the siRSK4 gene to establish a gastric cancer cell line with RSK4 inhibitory expression.qRT-PCR and Western blot(WB)analysis confirmed the low expression of RSK4 in the HGC-27 cell line,confirming that knockout of RSK4 is effective.The expression of RSK4 in the HGC-27 cell line transfected with RSK4-siRNA in the experimental group was significantly lower than that of the control group(P<0.001).The BTT-803 and HGC-27 human gastric cancer cell lines transfected with siRSK4 were significantly proliferated by MTT assay(P<0.001).PI flow cytometry detected a decrease in G0/1 phase cells and a significant increase in S phase cells(P<0.05).Apoptosis rate of cells after transfection by Annexin/PI was also lower than that of control group(P<0.05).Further chemotherapy showed that the apoptosis of gastric cancer cells in the experimental group decreased significantly(P<0.005).Scratch test and Transwell test showed thatmigration ability and invasion ability of the cells were significantly enhanced(P<0.05).ConclusionExperimental transfection of gastric cancer cell lines with RSK4-siRNA can silence RSK4 gene expression.Decreased expression of RSK can promote the growth and invasion of gastric cancer cells and reduce the apoptosis of cancer cells.It indicates that RSK4 gene can inhibit the proliferation and metastasis of gastric cancer cells,which may be a potential tumor suppressor gene,which can provide a biological basis for the therapeutic target of new targeted therapy in the treatment of gastric cancer.