The Role And Mechanism Research Of CDK5RAP3 Regulating MCM6 In Gastric Cancer

Objective:As one of the most common digestive tract tumors,gastric cancer ranks second place in the mortality of cancer and is a crucial disease that seriously affects people’s health.Gastric cancer has the characteristics of high incidence and high metastasis rate.Invasion and metastasis are the main causes of death in gastric cancer.However,the occurrence and development of gastric cancer is an extremely complicated process.The mechanism of metastasis has not been entirely elucidated.Therefore,the signal of invasion and metastasis in gastric cancer still required deep-going research and it is particularly important.In our previous studies,we found that the expression of CDK5RAP3(C53)can inhibit the proliferation,invasion,migration and growth of gastric cancer and is closely related to the prognosis of gastric cancer patients.To study the related complexes of C53,we performed mass spectrometry analysis and found that C53 has a strong correlation with MCM6,which is closely related to the initiation of DNA replication,was reported to be upregulated in multiple malignancies.To further elucidate the potential mechanism of C53 in the development of gastric cancer,this study aims to explore the role and mechanism research of C53 regulating MCM6 in Gastric Cancer,and provide new targets and interventions for the treatment of gastric cancer.Methods:First,we used mass spectrometry and co-immunoprecipitation to study the interaction between C53 and MCM6;then,we used lentiviruses to establish gastric cancer cell lines AGS and HGC-27 that stably knocked out the C53 gene,and rescue assay was used to observe the effect of C53 and MCM6 on cell proliferation;further,immunofluorescence and nucleoprotein extraction was perform to figure out the potential mechanism of C53 and MCM6;finally,immunohistochemistry and immunofluorescence was used to analyze the expression levels of C53 and MCM6 in136 patients with gastric cancer,and the impact and significance of C53 and MCM6 expression on the prognosis of gastric cancer patients were confirmed by Kaplan–Meier curves and cox proportional hazard regression analysis.Results:Mass spectrometry analysis showed that C53 has a strong correlation with MCM6,and C53 can co-immunoprecipitate with MCM6.Then,rescue assay confirmed that silencing MCM6 expression can reverse the proliferation,invasion,and migration of gastric cancer cells after silencing C53.Furthermore,cell immunofluorescence and nuclear protein extraction found that down-regulating the expression of C53 can promote the transfer of MCM6 to the nucleus.Finally,in the analysis of gastric cancer tissues and adjacent tissues of patients,immunohistochemistry and immunofluorescence were used to confirm that down-regulation of C53 can promote the transfer of MCM6 to the nucleus,and C53 and MCM6 are independent risk factors for the prognosis of gastric cancer patients,and are closely related to the T,N,and M stages of gastric cancer.Conclusions: C53 can bind to MCM6 and prevent MCM6 from being transferred from the cytoplasm to the nucleus,thereby exerting a tumor suppressing effect.At the same time,C53 and MCM6 are independent risk factors for the prognosis of gastric cancer patients,and are closely related to the T,N,and M stages of gastric cancer.