Study On The Effect Of CKS2 Gene On The Proliferation And Migration Of Prostate Cancer Cells And Its Upstream Targeted Regulatory Mechanis

Part 1 Selection of key genes in prostate cancer based on GEO and TCGA databasesObjective:To screen and identify key genes in prostate cancer through bioinformatics analysis,and explore their potential mechanisms.Methods:We used the GEO2R tool to screen for differentially expressed genes between prostate cancer and adjacent tissues in the GSE104749,GSE38241,and GSE46602 datasets.We constructed a protein-protein interaction network(PPI)using the STRING database for the proteins encoded by the differentially expressed genes.We used the MCODE plugin to identify core gene sub-modules in the PPI.Gene set enrichment analysis(GSEA)and survival analysis were performed on the core genes to determine their potential molecular mechanisms in the pathogenesis of prostate cancer.Results:A total of 174 differentially expressed genes in prostate cancer were identified from the GSE46602,GSE104749,and GSE38241 datasets.Through the MCODE plugin,we identified core gene sub-modules in the PPI network,including ANLN,AURKA,NCAPG,CCNB1,EZH2,CKS2,CDCA5,CENPU,BIRC5,RRM2,NUSAP1,CENPF,TOP2A,ECT2,and TK1.CKS2 was identified as a key star differentially expressed gene among the differentially expressed genes.The expression level of CKS2 was closely related to the pathological staging and poor prognosis in prostate cancer.GSEA analysis results showed that in patients with high CKS2 expression,cell proliferation-related pathways such as cell cycle and mismatch repair were significantly enriched.Conclusion:The expression level of CKS2 is closely related to the prostate cancer pathology staging and poor prognosis of patients,and CKS2 may regulate the occurrence and development of prostate cancer by affecting molecular pathways such as cell cycle and mismatch repair.Therefore,CKS2 is an important key gene in the development of prostate cancer and can be a potential biomarker and therapeutic target for the diagnosis and treatment of prostate cancer.Part 2 The effect of CKS2 on the biological behavior of prostate cancerObjective:To explore the expression level of CKS2 in pathological tissues of prostate cancer patients and its relationship with patient clinical characteristics,and to further verify its impact on prostate cancer biological behavior in cell lines.Methods:Pathological specimens and clinical information of 120 prostate cancer patients undergoing radical prostatectomy at Peking Union Medical College Hospital from 2020 to 2022 were collected.The expression level of CKS2 in prostate cancer and adjacent tissues was detected by immunohistochemistry,and the relationship between CKS2 expression level and patient clinical characteristics was analyzed.Human normal prostate cell lines RWPE-1 and prostate cancer cell lines 22Rv1 and PC3 were cultured,and the expression level of CKS2 was detected by qRT-PCR and Western blot.After knocking down the expression level of CKS2 by RNA interference,CCK-8,EdU,Transwell,and wound healing assays were performed.Results:The median H-score for immunohistochemical staining of CKS2 in prostate cancer tissues was 117,while that in adjacent normal tissues was 75.The expression level of CKS2 in prostate cancer tissues was significantly higher than that in adjacent normal tissues(P=0.043).The mRNA and protein levels of CKS2 in prostate cancer cell lines were both higher than those in normal prostate cell lines(P<0.01).After RNA interference was used to knock down the expression of CKS2 in prostate cancer cell lines,the proliferative and migratory abilities of prostate cancer cells were significantly weakened(P<0.05).Conclusion:The expression level of CKS2 is significantly elevated in prostate cancer tissues and has a promoting effect on the proliferation and migration of prostate cancer cells,suggesting that it may be a potential biomarker and therapeutic target for prostate cancer.Part 3 Downregulation of CKS2 by microRNA-26a inhibits proliferation and migration of prostate cancerObjective:To investigate the effect of microRNA-26a and its target gene CKS2 on the proliferation and migration ability of prostate cancer cell lines.Methods:CKS2 was predicted and verified as a target gene of microRNA-26a through bioinformatics methods and dual-luciferase reporter assays.The expression levels of microRNA-26a in prostate cancer cell lines and human normal prostate cell lines were detected by qRT-PCR.The effects of transfection with microRNA-26a mimic on the proliferation and migration ability of prostate cancer cell lines 22Rv1 and PC3 were observed by CCK-8 assay,colony formation assay,Transwell assay,and wound healing assay.Results:Bioinformatics prediction revealed that CKS2 is a potential target of microRNA26a.Dual-luciferase reporter assays confirmed that CKS2 is a downstream target gene of microRNA-26a.The expression level of microRNA-26a in prostate cancer cell lines is significantly lower than that in normal prostate cell lines(P<0.001).Transfection with microRNA-26a mimic significantly decreased the expression levels of CKS2 at both mRNA and protein levels(P<0.01).Transfection with microRNA-26a mimic significantly inhibited the proliferation and migration abilities of prostate cancer cells(P<0.05).Cotransfection of microRNA-26a and CKS2 revealed that CKS2 could eliminate the inhibitory effect of microRNA-26a on the proliferation and migration abilities of prostate cancer cells.Conclusion:CKS2 is a potential target of microRNA-26a,and the expression level of microRNA-26a is significantly decreased in prostate cancer cell lines.MicroRNA-26a can target CKS2 to inhibit the proliferation and migration abilities of prostate cancer cells.