CKS1B as a potential target for prognostic assessment and intervention in pancreatic cancer and its role in abnormal proliferation and cellular phenotype through mediation of cell cycle signaling pathways.

OBJECTIVES: To investigate the role of cell cycle protein-dependent kinase regulatory subunit 1B (CKS1B) in driving the aggressive and rapid proliferation observed in pancreatic cancer. METHODS: A comprehensive analysis was carried out using raw mRNA information and data from 2 databases: the cancer genome atlas and gene expression omnibus. The differential expression of CKS1B at the mRNA and tissue levels in cancer and adjacent paracancerous tissues were assessed. Additionally, the relationship of CKS1B expression and overall survival (OS) rate was investigated using Kaplan-Meier survival curves. Potential molecular mechanisms by which CKS1B may influence the biological characteristics of pancreatic cancer were explored using resources available within the encyclopedia of RNA interactomes database. RESULTS: The CKS1B exhibited significant differential expression at the mRNA as well as protein levels. A correlation with statistical significance between CKS1B expression and N stage, age, and alcohol consumption was observed. Notably, high CKS1B expression was determined as a predictive factor for worse OS. Furthermore, the analysis revealed a potential synergistic role between CKS1B and the molecule PKMYT1, which could impact the ATR-Chk1-Cdc25 signaling pathway and disrupt the G2/M checkpoint within the cell cycle, ultimately promoting abnormal tumor proliferation. CONCLUSION: The CKS1B may serve as a novel potential prognostic factor in pancreatic cancer and is involved in the abnormal proliferation biology phenotype by mediating cell cycle signaling pathways.

Prognostic significance of cyclin-dependent kinase subunit 2 (CKS2) in malignant tumours: a meta-analysis and bioinformatic analysis.

OBJECTIVES: This study aimed to systematically elucidate the prognostic significance of cyclin-dependent kinase subunit 2 (CKS2) expression in various cancers and its correlation with their clinicopathological characteristics. DESIGN: In this meta-analysis and bioinformatic analysis, articles were identified through searches of multiple databases and meta-analysed according to the Preferred Reporting Items for Systematic Review and Meta-analysis Protocols. Data from The Cancer Genome Atlas were examined using UCSC Xena tools to further confirm the prognostic effect of CKS2. DATA SOURCES: The PubMed, Embase, Web of Science and Cochrane Library databases were searched for articles published from their inception to 1 January 2023, using a combination of subject terms and free words, including 'CKS2', 'cancer', 'tumor', 'neoplasm', 'carcinoma', 'malignancy' and 'prognosis'. ELIGIBILITY CRITERIA: The analysis included cohort or case-control studies, reported in English, with malignancy diagnoses confirmed by pathological methods, available HRs and 95% CIs for overall survival (OS) or extractable Kaplan-Meier curves, and a sample size of ≥20 patients. Reviews, commentaries, letters, conference reports, case reports, in vitro and animal studies, studies of CKS2 gene variants, studies with sample cases from public databases and studies with unavailable survival or duplicated data were excluded. DATA EXTRACTION AND SYNTHESIS: Two researchers independently screened the articles, extracted the data and evaluated the quality of included studies using the Newcastle-Ottawa Scale. Meta-analysis and bioinformatic analyses were performed using the STATA and R software, respectively. RESULTS: The analysis included 13 retrospective studies encompassing 1348 cases across 10 cancer types. Nine studies involving 1124 patients examined the correlation between CKS2 expression levels and OS. A fixed-effects model analysis revealed a significant association between high CKS2 expression and reduced OS (HR=2.27, 95% CI=1.87 to 2.77, p<0.001). Furthermore, high CKS2 expression was significantly associated with advanced tumour stage (relative risk (RR) = 1.82, 95% CI=1.57 to 2.11, p<0.001), lymph node metastasis (RR=1.68, 95% CI=1.38 to 2.04, p<0.001), larger tumour size (RR=1.60, 95% CI=1.27 to 2.03, p<0.001) and lower differentiation grade (RR=1.57, 95% CI=1.29 to 1.90, p<0.001). CKS2 expression levels were not significantly correlated with patients' age (RR=1.11, 95% CI=0.99 to 1.26, p=0.071) or sex (RR=0.98, 95% CI=0.90 to 1.07, p=0.653). An assessment of the articles showed no significant publication bias, confirming the robustness of these findings. The bioinformatic analysis further confirmed CKS2 upregulation in the examined cancer types and its association with poor OS in glioma (HR=1.97, 95% CI=1.78 to 2.18, p=3.70×10-42), liver hepatocellular carcinoma (HR=1.56, 95% CI=1.31 to 1.86, p=3.50×10-7) and lung adenocarcinoma (HR=1.27, 95% CI=1.10 to 1.48, p=1.70×10-3). CONCLUSIONS: Elevated CKS2 expression is associated with poor prognosis in a subset of malignant tumours, highlighting its potential as a prognostic marker. PROSPERO REGISTRATION NUMBER: CRD42023394038.

DLGAP5 Regulates the Proliferation, Migration, Invasion, and Cell Cycle of Breast Cancer Cells via the JAK2/STAT3 Signaling Axis.

The aim of this study was to discover new biomarkers to detect breast cancer (BC), which is an aggressive cancer with a high mortality rate. In this study, bioinformatic analyses (differential analysis, weighted gene co-expression network analysis, and machine learning) were performed to identify potential candidate genes for BC to study their molecular mechanisms. Furthermore, Quantitative Real-time PCR and immunohistochemistry assays were used to examine the protein and mRNA expression levels of a particular candidate gene (DLGAP5). And the effects of DLGAP5 on cell proliferation, migration, invasion, and cell cycle were further assessed using the Cell Counting Kit-8 assay, colony formation, Transwell, wound healing, and flow cytometry assays. Moreover, the changes in the JAK2/STAT3 signaling-pathway-related proteins were detected by Western Blot. A total of 44 overlapping genes were obtained by differential analysis and weighted gene co-expression network analysis, of which 25 genes were found in the most tightly connected cluster. Finally, NEK2, CKS2, UHRF1, DLGAP5, and FAM83D were considered as potential biomarkers of BC. Moreover, DLGAP5 was highly expressed in BC. The down-regulation of DLGAP5 may inhibit the proliferation, migration, invasion, and cell cycle of BC cells, and the opposite was true for DLGAP5 overexpression. Correspondingly, silencing or overexpression of the DLGAP5 gene inhibited or activated the JAK2/STAT3 signaling pathway, respectively. DLGAP5, as a potential biomarker of BC, may impact the cell proliferation, migration, invasion, cell cycle, and BC development by modulating the JAK2/STAT3 signaling pathway.

Advanced stage, high-grade primary tumor ovarian cancer: a multi-omics dissection and biomarker prediction process.

Ovarian cancer (OC) incidence and mortality rates continue to escalate globally. Early detection of OC is challenging due to extensive metastases and the ambiguity of biomarkers in advanced High-Grade Primary Tumors (HGPTs). In the present study, we conducted an in-depth in silico analysis in OC cell lines using the Gene Expression Omnibus (GEO) microarray dataset with 53 HGPT and 10 normal samples. Differentially-Expressed Genes (DEGs) were also identified by GEO2r. A variety of analyses, including gene set enrichment analysis (GSEA), ChIP enrichment analysis (ChEA), eXpression2Kinases (X2K) and Human Protein Atlas (HPA), elucidated signaling pathways, transcription factors (TFs), kinases, and proteome, respectively. Protein-Protein Interaction (PPI) networks were generated using STRING and Cytoscape, in which co-expression and hub genes were pinpointed by the cytoHubba plug-in. Validity of DEG analysis was achieved via Gene Expression Profiling Interactive Analysis (GEPIA). Of note, KIAA0101, RAD51AP1, FAM83D, CEP55, PRC1, CKS2, CDCA5, NUSAP1, ECT2, and TRIP13 were found as top 10 hub genes; SIN3A, VDR, TCF7L2, NFYA, and FOXM1 were detected as predominant TFs in HGPTs; CEP55, PRC1, CKS2, CDCA5, and NUSAP1 were identified as potential biomarkers from hub gene clustering. Further analysis indicated hsa-miR-215-5p, hsa-miR-193b-3p, and hsa-miR-192-5p as key miRNAs targeting HGPT genes. Collectively, our findings spotlighted HGPT-associated genes, TFs, miRNAs, and pathways as prospective biomarkers, offering new avenues for OC diagnostic and therapeutic approaches.

Aberrant expression of CKS2 induced by ELK1 contributes to malignant progression of pancreatic cancer.

Cyclin-dependent kinase subunit 2 (CKS2) has been reported to promote various malignancies. This study investigated the functional role of CKS2 in pancreatic cancer (PC). An analysis of abnormally expressed genes and their prognostic value for PC was performed by using the Gene Expression Profiling Interactive Analysis (GEPIA) database and performing immunohistochemical staining on 64 samples of tumor tissue. CCK-8 assays, EdU staining, colony formation assays, flow cytometry, and a xenograft tumor model were used to analyze the biological function of CKS2 in PC. Our results revealed that CKS2 was expressed at significantly higher levels in PC tissues than in adjacent normal tissues, and a high level of CKS2 expression was associated with a poor prognosis for patients with PC. Moreover, functional assays revealed that CKS2 knockdown suppressed cell proliferation, induced cell cycle S phase, G2/M phase arrest, and apoptosis in vitro, and also reduced tumor growth in vivo. In addition, CKS2 knockdown increased the levels of Bax, caspase-3, P53, P21, and GADD45α expression, but decreased Bcl-2, Cyclin B1, CDK1, Cyclin A, and Cdc25C expression. CKS2 overexpression produced the opposite effects of CKS2 knockdown. Furthermore, we found that ELK1 protein regulated transcription of the CKS2 gene. In conclusion, our findings suggest that CKS2 expression is regulated by ELK1, which could possibly serve as prognostic indicator and therapeutic target for PC.

Cyclin-dependent kinase subunit2 (CKS2) promotes malignant phenotypes and epithelial-mesenchymal transition-like process in glioma by activating TGFß/SMAD signaling.

BACKGROUND: Gliomas are a group of primary intracranial tumors with high morbidity and mortality. The previous researches indicated a crucial role of CKS2 (cyclin-dependent kinases regulatory subunit 2) in hepatocellular carcinoma and breast cancer; however, little is known about the molecular mechanism of CKS2 in the tumorigenesis and epithelial-mesenchymal transition-like (EMT) process in glioma. METHODS: Datasets for bioinformatics analysis were obtained from the GEO, TCGA and CGGA databases. qRT-PCR, western blotting (WB), and immunohistochemistry (IHC) assays were used to investigate the expression patterns of CKS2 among glioma and brain tissues. Glioma cells were transfected with small interfering RNA/overexpression plasmid against CKS2, then clone formation assay, CCK-8, wound healing, Transwell assay, and flow cytometry were performed to detect changes in cell viability, invasiveness, and the apoptosis rate. Markers of cell invasion, apoptosis, EMT and TGFß/SMAD signaling were evaluated by WB and immunofluorescence (IF) assays. RESULTS: We found that CKS2 overexpression correlates with poor prognosis in human glioma and knockdown of CKS2 could inhibit cell proliferation, migration, invasion, and induced apoptosis in glioma cells. Besides, we also found that knockdown of CKS2 could reverse the EMT process via modulating EMT-related molecules. Glioma cells with overexpression of CKS2 were constructed to confirmed the fact that CKS2 induced nucleocytoplasmic translocation of SMAD2/3 and activated TGFß/SMAD pathway, then upregulated its downstream targets expression, while inhibition of TGFß/SMAD (by TGFß inhibitor LY2157299 or SMAD4 siRNA) could reverse the tumor-promoting effects and malignant phenotype caused by CKS2 overexpression. CONCLUSIONS: We identified CKS2 as a critical contributor to the gliomagenesis, which might provide a novel therapeutic target for inhibiting the spread and infiltration of glioma.

Identification of CKS1B as a prognostic indicator and a predictive marker for immunotherapy in pancreatic cancer.

As a regulatory subunit of cyclin kinase, CKS1B promotes cancer development and is associated with poor prognosis in multiple cancer patients. However, the intrinsic role of CKS1B in pancreatic cancer remains elusive. In our research, CKS1B expression in pancreatic tumor tissue was higher than that in normal tissue by TCGA, Oncomine and CPTAC databases analysis. Similar result was verified in our center tissues by qRT-PCR. CKS1B expression was closely relevant to histologic grading, prognosis, and TMB. GSEA showed that CKS1B mainly participated in the regulation of autophagy and T cell receptor signaling pathway. Furthermore, CIBERSORT analysis showed that there was a strong correlation between CKS1B expression and tumor immune cells infiltration. Drug sensitivity analysis showed that patients with high CKS1B expression appeared to be more sensitive to gemcitabine, 5-fluorouracil, and paclitaxel. We then investigated cell viability and migratory ability by CCK8 and transwell assay, respectively. Results indicated that CKS1B knockdown by short hairpin RNA significantly reduced pancreatic cancer cell viability and invasion via regulating PD-L1 expression. In conclusion, our research further demonstrates the role of CKS1B in pancreatic cancer and the signaling pathways involved. The association of CKS1B with immune infiltration and immune checkpoint may provide a new direction for immunotherapy of pancreatic cancer.

E2F1/CKS2/PTEN signaling axis regulates malignant phenotypes in pediatric retinoblastoma.

Retinoblastoma (RB) is the most common pediatric intraocular malignancy and is a serious vision- and life-threatening disease. The biallelic mutation of the retinoblastoma gene RB1 is the initial event in the malignant transformation of RB, but the exact molecular mechanism is still unclear. E2F transcription factors can be activated by RB1 loss of function and lead to uncontrolled cell division. Among E2F family numbers, E2F1 has higher expression abundance than E2F2 and E2F3 in RB clinical samples. By integrating E2F1 ChIP-seq data, RNA-seq profiling from RB samples and RNA-seq profiling upon E2F1 knockdown, together with pathway analysis, literature searching and experimental validation, we identified Cyclin-dependent kinases regulatory subunit 2 (CKS2) as a novel regulator in regulating tumor-associated phenotypes in RB. CKS2 exhibited aberrantly higher expression in RB. Depletion of CKS2 in Y79 retinoblastoma cell line led to reduced cell proliferation, delayed DNA replication and decreased clonogenic growth. Downregulation of CKS2 also slowed tumor xenograft growth in nude mice. Importantly, reversed expression of CKS2 rescued cancer-associated phenotypes. Mechanistically, transcription factor E2F1 enhanced CKS2 expression through binding to its promoter and CKS2 regulated the cancer-associated PI3K-AKT pathway. This study discovered E2F1/CKS2/PTEN signaling axis regulates malignant phenotypes in pediatric retinoblastoma, and CKS2 may serve as a potential therapeutic target for this disease.

Cyclin-Dependent Kinase Subunit 2 (CKS2) as a Prognostic Marker for Stages I-III Invasive Non-Mucinous Lung Adenocarcinoma and Its Role in Affecting Drug Sensitivity.

With the aim of improving the prognosis of patients with lung adenocarcinoma (LUAD), we identified the biomarker related to the sensitivity of patients to chemotherapy drugs and explored the potential mechanisms. As a cell cycle-related protein, CKS2 has an essential role to play in tumor progression and prognosis. CKS2 expression was measured using TCGA RNA-sequencing data and immunohistochemistry. The sensitivity data of tumor cells to chemotherapeutic drugs for lung cancer was acquired from the Cancer Therapeutics Response Portal (CTRP) database. A range of bioinformatics methods was used to explore the mechanisms of CKS2 upregulation. The biological functions of CKS2 were predicted using GO and KEGG enrichment analysis, as well as GSEA. CKS2 expression was up-regulated in stages I-III invasive non-mucinous lung adenocarcinoma and varied significantly between various histological subtypes. High CKS2 expression worsened the prognosis of patients. The CKS2 expression level was linked to the sensitivity of LUAD cells to carboplatin and paclitaxel. CKS2 upregulation was associated with the immune microenvironment, mRNA methylation, and competing endogenous RNAs (ceRNAs). CKS2 can serve as a diagnostic and prognostic biomarker for stages I-III invasive non-mucinous lung adenocarcinoma and modulate the effect of paclitaxel and carboplatin by regulating microtubule binding and influencing carboplatin binding to DNA.

Knockdown of replication protein A 3 induces protective autophagy and enhances cisplatin sensitivity in lung adenocarcinoma by inhibiting AKT/mTOR signaling via binding to cyclin-dependent kinases regulatory subunit 2.

Replication protein A 3 (RPA3) is a significant component of replication protein A and has been documented to function as an oncogene in several types of cancers. However, the role and underlying mechanism of RPA3 in lung adenocarcinoma (LUAD) remains unknown. In this study, messenger expression of RPA3 and survival probability in LUAD were predicted by the UALCAN database. The combination of RPA3 with cyclin-dependent kinases regulatory subunit 2 (CKS2) were characterized by the humanbase and STRING databases and verified by co-immunoprecipitation. Cell viability was assessed by Cell Counting Kit-8 assay and colony formation assay. Flow cytometric analysis and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling assay were used to determine cell cycle and cell apoptosis, respectively. The expressions of protein kinase B/mammalian target of rapamycin (AKT/mTOR) pathway and autophagy-related proteins were examined by western blot assay. Significantly, we revealed that RPA3 expression was upregulated in LUAD and is associated with poor prognosis in LUAD patients. RPA3 and CKS2 expression was highly expressed in LUAD cell lines and the interaction between RPA3 and CKS2 was confirmed. RPA3 silencing inhibited A549 cell viability, blocked cell cycle and promoted cell apoptosis, as well as induction of autophagy and inhibition of AKT/mTOR signaling. CKS2 overexpression reversed the effects of RPA3 silencing on A549 cells. In addition, RPA3 knockdown enhanced cisplatin sensitivity of A549 cells through blocking the AKT/mTOR signaling. These results suggested that RPA3 might control LUAD cell autophagy and enhance cisplatin sensitivity by regulation of AKT/mTOR signaling via targeting CKS2.

Identification of Critical Biomarkers and Immune Infiltration in Rheumatoid Arthritis Based on WGCNA and LASSO Algorithm.

Rheumatoid arthritis(RA) is the most common inflammatory arthritis, and a significant cause of morbidity and mortality. RA patients' synovial inflammation contains a variety of genes and signalling pathways that are poorly understood. It was the goal of this research to discover the major biomarkers related to the course of RA and how they connect to immune cell infiltration. The Gene Expression Omnibus was used to download gene microarray data. Differential expression analysis, weighted gene co-expression network analysis (WGCNA), and least absolute shrinkage and selection operator (LASSO) regression were used to identify hub markers for RA. Single-sample GSEA was used to examine the infiltration levels of 28 immune cells and their connection to hub gene markers. The hub genes' expression in RA-HFLS and HFLS cells was verified by RT-PCR. The CCK-8 assay was applied to determine the roles of hub genes in RA. In this study, we identified 21 differentially expressed genes (DEGs) in RA. WGCNA yielded two co-expression modules, one of which exhibited the strongest connection with RA. Using a combination of differential genes, a total of 6 intersecting genes was discovered. Six hub genes were identified as possible biomarkers for RA after a lasso analysis was performed on the data. Three hub genes, CKS2, CSTA, and LY96, were found to have high diagnostic value using ROC curve analysis. They were shown to be closely related to the concentrations of several immune cells. RT-PCR confirmed that the expressions of CKS2, CSTA and LY96 were distinctly upregulated in RA-HFLS cells compared with HFLS cells. More importantly, knockdown of CKS2 suppressed the proliferation of RA-HFLS cells. Overall, to help diagnose and treat RA, it's expected that CKS2, CSTA, and LY96 will be available, and the aforementioned infiltration of immune cells may have a significant impact on the onset and progression of the disease.

CKS2 and S100A12: Two Novel Diagnostic Biomarkers for Rheumatoid Arthritis.

Rheumatoid arthritis (RA) is a chronic systematicness autoimmunity disease with joint inflammation. RA etiology is still unknown. Early and exact diagnosing is still hard to reach. In the paper, we purposed to discover novel diagnosis biological marker for RA. Two open, usable gene expression profiles of human RA as well as controlled specimens (dataset GSE17755 as well as GSE93272) were downloaded from the GEO database. Differentially expressed genes (DEGs) were screened between 331 RA and 88 control samples. Functional enrichment analysis was applied to explore the possible function of DEGs. Expression levels as well as diagnosis values of biological marker in RA were further verified in our cohort by the use of RT-PCR and ROC assays. We identified 13 DEGs between RA samples and control samples. 13 DEGs were remarkably abundant in NF-kappa B signal pathway. Among the 13 DEGs, CKS2, S100A12, LY96, and ANXA3 exhibited a strong diagnostic ability in screening RA specimens from normal specimens using all AUC > 0.8. Moreover, we confirmed that the expression of CKS2 and S100A12 was distinctly upregulated in RA specimens contrasted to normal specimens. Overall, serum CKS2 and S100A12 could be used as novel diagnosis biological markers for RA patients.

Errate: Identification of NDRG Family Member 4 (NDRG4) and CDC28 Protein Kinase Regulatory Subunit 2 (CKS2) as Key Prognostic Genes in Adrenocortical Carcinoma by Transcriptomic Analysis.

The original published paper had the same image for Figure 5E and 5F. Figure 5 should have been as follows: Reference: Zhengqing Yang, Hui Cheng, Yazhou Zhang, Yan Zhou. Identification of NDRG Family Member 4 (NDRG4) and CDC28 Protein Kinase Regulatory Subunit 2 (CKS2) as Key Prognostic Genes in Adrenocortical Carcinoma by Transcriptomic Analysis. Med Sci Monit, 2021; 27:e928523. DOI: 10.12659/MSM.928523.

High Expression of CKS2 Predicts Adverse Outcomes: A Potential Therapeutic Target for Glioma.

Cyclin-dependent kinase regulatory subunit 2 (CKS2) is a potential prognostic marker and is overexpressed in various cancers. This study analyzed sequencing and clinical data from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus, with external validation using the Chinese Glioma Genome Atlas (CGGA) data. CKS2 expression in the normal brain and tumor tissue was compared. cBioPortal and MethSurv were utilized to scrutinize the prognostic value of CKS2 methylation. Gene set enrichment examination and single-sample gene set enrichment analysis were employed to explore the potential biological functions of CKS2. Cell viability, colony formation, and transwell assays were conducted to evaluate the influence of CKS2 on glioma cell proliferation and invasion. Compared with normal brain tissue, the expression of CKS2 was upregulated in glioma samples (p < 0.001). Multivariate data analysis from TCGA and CGGA indicated that increased expression of CKS2 was an independent risk factor for the prognosis of overall survival in glioma patients. CKS2 methylation was negatively associated with CKS2 expression. Patients with CKS2 hypomethylation had worse overall survival compared with patients with CKS2 methylation, as suggested by the analysis of both TCGA and CGGA datasets. The expression level of CKS2 is closely related to tumor immunity, including the correlation of tumor immune cell infiltration, immune score, and co-expression of multiple immune-related genes. In addition, CKS2 is associated with several immune checkpoints and responses to the chemotherapy drug cisplatin. CKS2 knockdown impeded the expansion and aggression of glioma cell lines. The changes in CKS2 expression may provide a novel prognostic biomarker that can be used to improve patient overall survival rates.

Expression Profile and Molecular Basis of Cyclin-Dependent Kinases Regulatory Subunit 2 in Endometrial Carcinoma Detected by Diversified Methods.

Purpose: Our purpose was to systematically appraise the clinicopathological significance and explore the molecular bases of CKS2 in endometrial carcinoma. Patients and Methods: We measured the clinicopathological significance of CKS2 using diverse methods of public RNA-seq, microarrays, and in-house tissue microarrays to investigate the molecular basis of CKS2 in endometrial carcinoma through upstream transcriptional analysis, immune infiltration correlation analysis, and co-expression analysis. Results: Both the analysis for public RNA-seq plus the microarray data and in-house tissue microarray confirmed the significant overexpression of CKS2 in a total of 1,021 endometrial carcinoma samples compared with 279 non-cancer endometrium samples (SMD = 2.10, 95% CI = 0.72-3.48). The upregulated CKS2 was significantly related to the lymph node metastasis and advanced clinical grade of endometrial carcinoma patients (p < 0.001). Mutation types such as amplification and mRNA occurred with high frequency in the CKS2 gene in endometrial carcinoma patients. A series of miRNAs and transcription factors, such as hsa-miR-26a, hsa-miR-130a, hsa-miR-30, E2F4, MAX, and GABPA, were predicted to regulate the transcription and expression of CKS2. Significant links were found between CKS2 expression and the infiltration level of B cells, CD4+ T cells, and neutrophils in endometrial carcinoma. CKS2-coexpressed genes were actively involved in pathways such as the mitotic cell cycle process, PID aurora B pathway, and prolactin signaling pathway. Conclusion: The overexpressed CKS2 showed positive correlations with the clinical progression of endometrial carcinoma and was associated with various cancer-related biological processes and pathways, showing potential as a promising clinical biomarker for endometrial carcinoma.

Targeting the untargetable: RB1-deficient tumours are vulnerable to Skp2 ubiquitin ligase inhibition.

Proteins that regulate the cell cycle are accumulated and degraded in a coordinated manner during the transition from one cell cycle phase to the next. The rapid loss of a critical protein, for example, to allow the cell to move from G1/G0 to S phase, is often regulated by its ubiquitination and subsequent proteasomal degradation. Protein ubiquitination is mediated by a series of three ligases, of which the E3 ligases provide the specificity for a particular protein substrate. One such E3 ligase is SCFSkp1/Cks1, which has a substrate recruiting subunit called S-phase kinase-associated protein 2 (Skp2). Skp2 regulates cell proliferation, apoptosis, and differentiation, can act as an oncogene, and is overexpressed in human cancer. A primary target of Skp2 is the cyclin-dependent kinase inhibitor p27 (CDKN1b) that regulates the cell cycle at several points. The RB1 tumour suppressor gene regulates Skp2 activity by two mechanisms: by controlling its mRNA expression, and by an effect on Skp2's enzymatic activity. For the latter, the RB1 protein (pRb) directly binds to the substrate-binding site on Skp2, preventing protein substrates from being ubiquitinated and degraded. Inactivating mutations in RB1 are common in human cancer, becoming more frequent in aggressive, metastatic, and drug-resistant tumours. Hence, RB1 mutation leads to the loss of pRb, an unrestrained increase in Skp2 activity, the unregulated decrease in p27, and the loss of cell cycle control. Because RB1 mutations lead to the loss of a functional protein, its direct targeting is not possible. This perspective will discuss evidence validating Skp2 as a therapeutic target in RB1-deficient cancer.

Clinicopathological value of the upregulation of cyclin-dependent kinases regulatory subunit 2 in osteosarcoma.

BACKGROUND: Cyclin-dependent kinase subunit 2 (CKS2) is a member of cyclin dependent kinase subfamily and the relationship between CKS2 and osteosarcoma (OS) remains to be further analyzed. METHODS: 80 OS and 41 non-tumor tissue samples were arranged to perform immunohistochemistry (IHC) to evaluate CKS2 expression between OS and non-tumor samples. The standard mean deviation (SMD) was calculated based on in-house IHC and tissue microarrays, and exterior high-throughput datasets for further verification of CKS2 expression trend in OS. The effect of CKS2 expression on clinicopathological parameters of OS patients, and single-cell in OS tissues was analyzed through public high-throughput datasets and functional enrichment analysis was conducted for co-expression genes of CKS2 in accordance with weighted correlation network analysis. RESULTS: A total of 217 OS samples and 87 non-tumor samples (including tissue and cell line) were obtained from in-house IHC, microarrays and exterior high-throughput datasets. The analysis of integrated expression status demonstrated up-regulation of CKS2 in OS (SMD = 1.57, 95%CI [0.27-2.86]) and the significant power of CKS2 expression in distinguishing OS samples from non-tumor samples (AUC = 0.97 95%CI [0.95-0.98]). Clinicopathological analysis of GSE21257 indicated that OS patients with higher CKS2 expression was more likely to suffer OS metastasis. Although Kaplan-Meier curves showed no remarkable difference of overall survival rate between OS patients with high and low-CKS2, CKS2 was found up-regulated in proliferating osteosarcoma cells. Co-expression genes of CKS2 were mainly assembled in function and pathways such as cell cycle, cell adhesion, and intercellular material transport. CONCLUSIONS: In summary, up-regulation of CKS2 expression in OS tissue was found through multiple technical approaches. In addition, scRNA-seq and co-expression analysis showed that CKS2 may have an impact on important biological process linked with cell cycle, cell adhesion, and intercellular material transport. Present study on CKS2 in OS indicated a promising prospect for CKS2 as a biomarker for OS.

Identification of hub genes in chronic pancreatitis and analysis of association with pancreatic cancer via bioinformatic analysis.

Chronic pancreatitis (CP), a fibroinflammatory disease, is a potential risk factor for pancreatic cancer. This study attempted to identify and analyze the key genes involved in CP development and their association with pancreatic cancer. The GSE41418 dataset was obtained from the Gene Expression Omnibus database. Gene ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses were performed on common differentially expressed genes. A protein-protein interaction network was constructed by using the STRING database. The expression and prognostic value of hub genes in pancreatic cancer were analyzed by Gene Expression Profiling Interactive Analysis (GEPIA) and UALCAN databases. The results showed that the upregulated genes primarily focused on the cell cycle, DNA replication, and phagosome activity. The PPI network was composed of 184 nodes and 925 edges. The 10 hub genes were screened by CytoHubba, of which CCNB2, CDC6, CDK1 and CKS2 were observed to be differentially expressed in pancreatic cancer with CP, and all of them were detrimental to overall survival and recurrence-free survival of pancreatic cancer. In this study, we employed bioinformatic analysis to determine that CCNB2, CDC6, CDK1 and CKS2 may be key genes in the development of CP and pancreatic cancer.

Regulation of microRNA miR-197-3p/CDC28 protein kinase regulatory subunit 1B (CKS1B) axis by Circular RNA hsa_circ_0000285 promotes glioma progression.

Circular RNA circ_0000285 is differentially expressed in several malignancies; however, its role in gliomas is under investigation. Reverse transcription quantitative polymerase chain reaction was conducted to evaluate the expression of circ_0000285, miR-197-3p, and CDC28 protein kinase regulatory subunit 1B (CKS1B) in glioma tissues and cells. Cell Counting Kit-8 and Transwell invasion assays coupled with Western blotting analysis using anti-Bax and anti-Bcl-2 antibodies were performed to evaluate cell proliferation, invasion, and apoptosis. Luciferase reporter and AGO2 RNA immunoprecipitation assays were conducted to verify the interaction between miR-197-3p and circ_0000285 or CKS1B. Xenograft tumor growth was evaluated in mice. We noted that circ_0000285 was highly expressed in glioma tissues and cells and that circ_0000285-silencing retarded tumor growth both in vitro and in vivo. This effect was mediated by the binding of circ_0000285 to miR-197-3p, which silenced CKS1B, an essential driver of glioma cell proliferation and invasion. Thus, circ_0000285 boosted glioma progression by regulating the miR-197-3p/CKS1B axis, highlighting a novel competing endogenous RNA circuit of glioma progression.

Overexpression of Parkin in clear cell renal cell carcinoma decreases tumor aggressiveness by regulating CKS2 levels.

Low expression levels of the E3 ubiquitin­protein ligase Parkin (PARK2) are exhibited in several cancer entities, including clear cell renal cell carcinoma (ccRCC), and are associated with poor prognosis; however, PARK2 can also function as a tumor suppressor gene. The aim of the present study was to thoroughly investigate the effects of PARK2 overexpression in ccRCC cell lines and to determine its effects on malignancy by conducting functional assays such as cell cycle analysis, apoptosis analysis, migration and invasion assays. Furthermore, liquid chromatography­mass spectrometry was used to decipher potential targets of PARK2 that may influence the behavior of ccRCC tumor cells. In addition, ccRCC tumor tissues from a patient cohort were examined in tissue microarrays to find correlations between different clinical parameters. In the present study, it was demonstrated that the induction of PARK2 resulted in a less aggressive phenotype, as indicated by lower migration and invasion in ccRCC cell lines. Mass spectrometry revealed decreased levels of 29 proteins in cells with PARK2 overexpression, including CDC28 protein kinase regulatory subunit 2 (CKS2), which is highly expressed in numerous types of cancer. The link between the function of PARK2 as an E3 ubiquitin ligase and the low expression levels of CKS2 was investigated by mutating the catalytic domain of the PARK2 gene, and it was found that the effect of decreased migration was abolished in 786­O and RCC­MH ccRCC cell lines. CKS2 silencing decreased migratory ability of the cells. Furthermore, it was revealed that high CKS2 levels are associated with high tumor grading in patient samples and lower patient survival. In conclusion, the results from the present study indicated that PARK2 may signal via CKS2 to affect tumor behavior. In consequence, CKS2 may be a biomarker in ccRCC and may also serve as potential target for ccRCC therapy.