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Objective To study the effect of epithelial cell transformation sequence 2 (ECT2) on the proliferation of cervical cancer cells and its mechanism. Methods We transfected cervical cancer cells HeLa (HeLa-ECT2) with the lentivirus overexpressing ECT2 and the cells SiHa (SiHa-siRNA) and C33a (C33a-siRNA) with the interfering plasmid. MTT assay was performed to detect cell proliferation ability. Flow cytometry was conducted to detect the cell cycle of each group. The IPA database was searched for the interacting proteins of ETC2, and immunofluorescence subcellular localization verified the effect between the two. qPCR and Western blot were carried out to detect the expression of Rac1, Cdc42, CDK1, and Cyclin B1 mRNA and protein in each group of cells. Results ECT2 may interact with CDK1. After ECT2 expression was upregulated, the G2/M phase of HeLa-ECT2 cells accelerated the transformation to G1 phase, cell proliferation ability was enhanced, and the expression levels of Rac1, Cdc42, CDK1, and cyclin B1 mRNA and protein all increased (P < 0.001); the knockdown of ECT2 expression would reverse the effect (P < 0.05). Conclusion ECT2 accelerates G2 phase of cervical cancer cells to G1 phase and promotes cell proliferation by co-localizing with CDK1 through the downstream Cdc42/Rac1 signaling pathway.
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Cyclin-dependent kinase 1 is a highly conserved serine/threonine kinase that acts as a checkpoint during mitosis, coordinating and promoting cell cycle progression. CDK1 is significantly upregulated in hepatocellular carcinoma. It is mainly related to p53 signal transduction pathway, LINC00346-miR-199a-3p-CDK1/CyclinB pathway, SNHG16/let-7b-5P/CDC25B/CDK1 pathway and UPF1-SNord52-CDK1 pathway. In this paper, the mechanism of CDK1 involvement in the occurrence and development of hepatocellular carcinoma was systematically elaborated, and the current situation of CDK1 inhibitor targeted treatment of HCC was clarified, which could provide clues and basis for the treatment of HCC with CDK1 as the target.
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@#Objective To analyze the expression and clinical significance of cyclin-dependent kinase 1 (CDK1) in lung adenocarcinoma by bioinformatics. Methods Based on the gene expression data of lung adenocarcinoma patients in The Cancer Genome Atlas (TCGA), the differential expression of CDK1 in lung adenocarcinoma tissues and normal lung tissues was analyzed. The expression of CDK1 gene in lung adenocarcinoma was analyzed by UALCAN at different angles. Survival analysis of different levels of CDK1 gene expression in lung adenocarcinoma was performed using Kaplan-Meier Plotter. Correlation Cox analysis of CDK1 expression and overall survival was based on clinical data of lung adenocarcinoma in TCGA. Gene set enrichment analysis was performed on gene sequences related to CDK1 expression in clinical cases. The protein interaction network of CDK1 from Homo sapiens was obtained by STRING. CDK1-related gene proteins were obtained and analyzed by the web server Gene Expression Profiling Interactive Analysis (GEPIA). Results Based on the analysis of TCGA gene expression data, CDK1 expression in lung adenocarcinoma was higher than that in normal lung tissues. UALCAN analysis showed that high CDK1 expression may be associated with smoking. Survival analysis indicated that when CDK1 gene was highly expressed, patients with lung adenocarcinoma had a poor prognosis. Univariate and multivariate Cox regression analysis of CDK1 expression and overall survival showed that high CDK1 expression was an independent risk factor for survival of patients with lung adenocarcinoma. Gene set enrichment analysis revealed that high CDK1 expression was closely related to DNA replication, cell cycle, cancer pathway and p53 signaling pathway. Conclusion CDK1 may be a potential molecular marker for prognosis of lung adenocarcinoma. In addition, CDK1 regulation may play an important role in DNA replication, cell cycle, cancer pathway and p53 signaling pathway in lung adenocarcinoma.
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10.3969/j.issn.1008-9691.2013.03.005
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OBJECTIVE: The BCL2 family proteins are critical mediators of cellular apoptosis and, as such, have been implicated as determinants of cancer cell chemo-sensitivity. Recently, it has been demonstrated that the phosphorylation status of the BCL2 antagonist of cell death (BAD) protein may influence ovarian cancer (OVCA) cell sensitivity to cisplatin. Here, we sought to evaluate how kinase and phosphatase components of the BAD apoptosis pathway influence OVCA chemo-sensitivity. METHODS: Protein levels of cyclin-dependent kinase 1 (CDK1) and protein phosphatase 2C (PP2C) were measured by immunofluorescence in a series of 64 primary advanced-stage serous OVCA patient samples. In parallel, levels of cAMP-dependent protein kinase (PKA), AKT, and PP2C were quantified by Western blot analysis in paired mother/daughter platinum-sensitive/resistant OVCA cell lines (A2008/C13, A2780S/A2780CP, Chi/ChiR). BAD pathway kinase CDK1 was depleted using siRNA transfection, and the influence on BAD phosphorylation and cisplatin-induced apoptosis was evaluated. RESULTS: OVCA patient samples that demonstrated complete responses to primary platinum-based therapy demonstrated 4-fold higher CDK1 (p<0.0001) and 2-fold lower PP2C (p=0.14) protein levels than samples that demonstrated incomplete responses. Protein levels of PP2C were lower in the platinum-resistant versus that shown in the platinum-sensitive OVCA cell line sub-clones. Levels of PKA were higher in all platinum-resistant than in platinum-sensitive OVCA cell line sub-clones. Selective siRNA depletion of CDK1 increased sensitivity to cisplatin-induced apoptosis (p<0.002). CONCLUSION: BAD pathway kinases and phosphatases, including CDK1 and PP2C, are associated with OVCA sensitivity to platinum and may represent therapeutic opportunities to enhance cytotoxic efficacy.