Cyclin-dependent Kinase Regulatory Subunit Research Articles

Involvement of CKS1B in the anti-inflammatory effects of cannabidiol in experimental stroke models

We have previously demonstrated that treatment with cannabidiol (CBD) ameliorates mitochondrial dysfunction and attenuates neuronal injury in rats following cerebral ischemia. However, the role of CBD in the progression of ischemic stroke-induced inflammation and the molecules involved remain unclear. Here, we found that CBD suppressed the production of interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α), reduced the activation of microglia, ameliorated mitochondrial deficits, and decreased the phosphorylation of nuclear factor κ-B (NF-κB) in BV-2 cells subjected to oxygen-glucose deprivation/reoxygenation (OGD/R). Cyclin-dependent kinase regulatory subunit 1B (CKS1B) expression was decreased in BV-2 cells following OGD/R and this reduction was blocked by treatment with CBD. Knockdown of CKS1B increased the activation of microglia and enhanced the production of IL-1β and TNF-α in BV-2 cells treated with CBD. Moreover, CKS1B knockdown exacerbated mitochondrial deficits and increased NF-κB phosphorylation. CBD treatment also ameliorated brain injury, reduced neuroinflammation, and enhanced the protein levels of mitochondrial transcription factor A and CKS1B in rats following middle cerebral artery occlusion/reperfusion. These data identify CKS1B as a novel regulator of neuroinflammation; and reveals its involvement in the anti-inflammatory effects of CBD. Interventions targeting CKS1B expression are potentially promising for treating in ischemic stroke.

A novel missense variant in CDK5RAP2 associated with non-obstructive azoospermia

ObjectiveThe most severe type of male infertility is non-obstructive azoospermia (NOA), where there is no sperm in the ejaculate due to failure of spermatogenesis, affecting 10%–20% of infertile men with azoospermia. Genetic studies have identified dozens of NOA genes. The main aim of the present study is to identify a novel monogenic mutation that may cause NOA. Materials and methodsWe studied the pedigree of a consanguineous family with three NOA and one fertile brother by a family-based exome-sequencing, segregation analysis, insilico protein modeling and single-cell RNA sequencing data analysis. ResultsBioinformatics analysis followed by sanger sequencing revealed that three NOA brothers were homozygous for a rare missense variant in Cyclin Dependent Kinase Regulatory Subunit Associated Protein 2 (Centrosomin) CDK5RAP2 (NM_018249:exon26:c.A4003T:p.R1335W, rs761196443). Protein modeling demonstrated that CDK5RAP2, Arg1335Trp resided nearby the Microtubule Associated Protein RP/EB Family Member 1 (EB1/MAPRE1) interaction site. As a consequence of the R1335W mutation, the positively charged Arginine was replaced by to the hydrophobic tryptophan residue, possibly leading to local instability in the structure and perturbation in the CDK5RAP2-MAPRE1 interaction. ConclusionOur study reports a novel missense variant of CDK5RAP2 that segregates in homozygosity with male infertility and NOA in a consanguineous family. In silico structural predictions and gene expression data indicate a potential role of the CDK5RAP2 variant in causing defective centrosomic maturation during spermatogenesis.

Expression of CKS2 in Hepatocellular Carcinoma: Correlation with Survival Outcomes and Immune Microenvironment.

Cyclin-dependent kinase regulatory subunit 2 (CKS2) has an important function in regulating cancer progression and cell cycle. This research aims to ascertain how CKS2 plays its part through multi-omics analyses, to reveal its relationship with the immune microenvironment in hepatocellular carcinoma (HCC). Multiple databases were used to determine the transcriptional data of CKS2, epigenetic changes, and effects thereof upon the prognosis of HCC patients. The biological functions of CKS2 in HCC were expounded by functional enrichment analysis. TIMER, GSEA, TIP, and online single-cell sequencing databases were adopted for revealing correlations of CKS2 expression with infiltration of immune cells, immunomodulators, immunity cycle, and immune markers in the immune microenvironment of HCC. In addition, qRT-PCR and Western blot were used to validate gene expression in tissues from HCC patients. Open database analysis confirmed that CKS2 is highly expressed in HCC and that it is related to poor prognosis in HCC patients. Aberrant methylation levels of the two methylation sites of CKS2 in HCC contributed to its high expression and were correlated significantly with survival. The CKS2 expression was positively correlated with most immunomodulators and infiltration levels for B and CD8+T cells, dendritic cells, and macrophages, especially exhausted CD8+T cells. Besides, the CKS2 expression was also found to have significant correlations with immunity cycle steps and diverse immune markers in HCC. The high CKS2 expression was confirmed in HCC at both mRNA and protein levels, showing a significant increase compared to normal tissue. CKS2 is a potential prognostic biomarker of HCC and can promote the progression of HCC via its influences on the immune environment. Additionally, a positive correlation between CKS2 and immune markers was observed, highlighting its potential as an immunotherapeutic target.

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

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. 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 TGFβ/SMAD signaling were evaluated by WB and immunofluorescence (IF) assays. 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 TGFβ/SMAD pathway, then upregulated its downstream targets expression, while inhibition of TGFβ/SMAD (by TGFβ inhibitor LY2157299 or SMAD4 siRNA) could reverse the tumor-promoting effects and malignant phenotype caused by CKS2 overexpression. 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.

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.

Identification of G6PC as a potential prognostic biomarker in hepatocellular carcinoma based on bioinformatics analysis.

Hepatocellular carcinoma (HCC) has high mortality and incidence rates around the world with limited therapeutic options. There is an urgent need for identification of novel therapeutic targets and biomarkers for early diagnosis and predicting patient survival with HCC.Several studies (GSE102083, GSE29722, GSE101685, and GSE112790) from the GEO database in HCC were screened and analyzed by GEO2R, gene ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analysis were conducted with the Database for Annotation, Visualization and Integrated Discovery. The protein-protein interaction network was plotted and the module analysis was performed using Search Tool for the Retrieval of Inter-acting Genes/Proteins database and Cytoscape. The expression and survival of key genes were identified using UALCAN, Kaplan–Meier Plotter and ONCOMINE online databases, and the immune infiltration level of key genes was analyzed via the Tumor Immune Estimation Resource (TIMER) database.Through database analysis, eight key genes were finally screened out, and the expressions of cyclin-dependent kinase regulatory subunit 2 and glucose-6-phosphatase catalytic (G6PC), which were closely related to the survival of HCC patients, was detected by using UALCAN. Further analysis on the differential expression of G6PC in multiple cancerous tumors and normal tissues revealed low expression in many solid tumors by Oncomine and TIMER. In addition, Kaplan–Meier plotter and UALCAN database analysis to access diseases prognosis suggested that low expression of G6PC was significantly associated with poor overall survival in HCC patients. Finally, TIMER database analysis showed a significant negative correlation between G6PC and infiltration levels of six kinds of immune cells. The somatic copy number alterations of G6PC were associated with B cells, CD8+ T cells, CD4+ T cells, macrophages, dentritic cells and neutrophils.These bioinformatic data identified G6PC as a potential key gene in the diagnosis and prognosis of HCC.

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 Aand 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.

CKS1 inhibition depletes leukemic stem cells and protects healthy hematopoietic stem cells in acute myeloid leukemia.

Acute myeloid leukemia (AML) is an aggressive hematological disorder comprising a hierarchy of quiescent leukemic stem cells (LSCs) and proliferating blasts with limited self-renewal ability. AML has a dismal prognosis, with extremely low two-year survival rates in the poorest cytogenetic risk patients, primarily due to the failure of intensive chemotherapy protocols to deplete LSCs, and the significant toxicity towards healthy hematopoietic cells. Whilst much work has been done to identify genetic and epigenetic vulnerabilities in AML LSCs, little is known about protein homeostasis in drug resistance and relapse. By targeting the proteostatic regulator CKS1, we demonstrate a dual role for CKS1-dependent protein degradation in reducing AML blasts in vivo, and importantly depleting LSCs, whilst inhibition of CKS1 has the opposite effect on normal hematopoiesis, protecting normal hematopoietic stem cells from chemotherapeutic toxicity. Together these findings demonstrate CKS1-dependent proteostasis is a key vulnerability in malignant stem cell biology.

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.

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.

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

BackgroundCyclin-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.Methods80 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.ResultsA 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.ConclusionsIn 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 novel hub genes associated with lymph node metastasis of head and neck squamous cell carcinoma by completive bioinformatics analysis.

BackgroundHead and neck squamous cell carcinoma (HNSCC) is one of the most serious diseases affecting populations worldwide and lymph node metastasis is a key pathological feature of HNSCC which predicts poor survival. However, the molecular mechanisms associated with the development of lymph node metastasis in HNSCC have not been fully elucidated.MethodsDifferentially expressed genes (DEGs) were identified in two HNSCC datasets (GES6631 and GES58911). Functional annotation analysis was constructed via Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses. Meanwhile, the protein-protein interaction (PPI) network and module analysis using Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) and Cytoscape were carried out to identify the hub genes. The expression differences, overall survival (OS), and disease-free survival (DFS) of hub genes were analyzed by Gene Expression Profiling Interactive Analysis 2 (GEPIA2) and verified by immunohistochemistry (IHC) from Human Protein Atlas (HPA). Moreover, receiver operating characteristic (ROC) curve analysis was conducted to judge whether those hub genes had good diagnostic and prognostic ability, and the web tool Tumor Immune Estimation Resource (TIMER) was used to analyze the correlation of hub genes’ expression and immune infiltration.ResultsIn total, 913 DEGs including 476 upregulated and 437 downregulated genes were identified. The genes Aurora kinase A (AURKA), CyclinB1 (CCNB1), Cyclin-dependent kinase regulatory subunit 1B (CKS1B), Serpin Family H Member 1(SERPINH1), and Transforming growth factor-beta-induced protein (TGFBI) were screened out as hub genes and were associated with lymph node metastasis, showing notably abnormal expression in HNSCC samples, and the high expression of all the hub genes in HNSCC patients was related to worse overall survival.ConclusionsThe genes AURKA, CCNB1, CKS1B, SERPINH1, and TGFBI may be involved in the lymph node metastasis of HNSCC and reveal the potential to serve as molecular biomarkers in the diagnosis of HNSCC. This study may help to elucidate the molecular mechanisms of the development of lymph node metastasis and facilitate the selection of targets for the treatment and diagnosis of HNSCC.

Establishment of high-throughput screening HTRF assay for identification small molecule inhibitors of Skp2-Cks1

S-phase kinase associated protein 2 (Skp2), a member of the F-box family that constitute the largest known class of ubiquitin E3 specificity components, is responsible for recognizing and recruiting cyclin-dependent kinase inhibitor p27 for its ubiquitination in the presence of the small accessory protein cyclin-dependent kinase regulatory subunit 1(Cks1). Skp2 is overexpressed in esophageal carcinoma tissues and closely related with tumor poor prognosis, and perturbation of the Skp2-Cks1 interaction by inhibitors or RNAi could inhibit the proliferation and metastasis of tumor cells. Therefore, inhibition of Skp2 function by small-molecule compounds targeting Skp2-Cks1 interaction is emerging as a promising and novel anti-cancer strategy. In this study, we establish an improved high-throughput screening platform to screen Skp2 inhibitors targeting Skp2-Cks1interaction, which may provide a new therapeutic approach for the clinic.

Knockdown of LINC00657 inhibits the viability, migration and invasion of pancreatic cancer cells by regulating the miR-520h/CKS1B axis.

Long non-coding RNA LINC00657 has a critical role in multiple cancers. The aim of the present study was to investigate the regulatory effect of LINC00657 in pancreatic cancer (PC) and reveal its molecular mechanism of function. The expression levels of LINC00657 and microRNA (miR)-520h were detected by reverse transcription-quantitative PCR in PC tissues and cell lines. MTT, wound healing and Transwell assays were used to detect cell viability, migration and invasion, respectively. Dual-luciferase reporter assay was utilized to examine the relationship between LINC00657 and miR-520h and that between miR-520h and cyclin-dependent kinases regulatory subunit 1 (CKS1B). Western blotting was performed to detect CKS1B expression. The expression levels of LINC00657 and CKS1B were enhanced and miR-520h expression level was reduced in PC tissues and cell lines compared with adjacent normal tissues or HPDE6 cells. LINC00657 knockdown decreased the viability, migration and invasion of PC cells. Additionally, LINC00657 targeted miR-520h and negatively modulated miR-520h expression. Furthermore, miR-520h overexpression inhibited the viability, migration and invasion of PC cells. In addition, miR-520h targeted CKS1B and reversely regulated CKS1B expression. miR-520h inhibition and CKS1B overexpression alleviated the inhibition effect of LINC00657 knockdown on the viability, migration and invasion of PACA-2 PC cells. In conclusion, the results of the present study demonstrated that LINC00657 knockdown repressed the viability, migration and invasion of PC cells via targeting the miR-520h/CKS1B axis, which may offer a future target for PC therapy.

OTUD6A Is an Aurora Kinase A-Specific Deubiquitinase.

Aurora kinases are serine/threonine kinases required for cell proliferation and are overexpressed in many human cancers. Targeting Aurora kinases has been a therapeutic strategy in cancer treatment. Here, we attempted to identify a deubiquitinase (DUB) that regulates Aurora kinase A (Aurora-A) protein stability and/or kinase activity as a potential cancer therapeutic target. Through pull-down assays with the human DUB library, we identified OTUD6A as an Aurora-A-specific DUB. OTUD6A interacts with Aurora-A through OTU and kinase domains, respectively, and deubiquitinates Aurora-A. Notably, OTUD6A promotes the protein half-life of Aurora-A and activates Aurora-A by increasing phosphorylation at threonine 288 of Aurora-A. From qPCR screening, we identified and validated that the cancer gene CKS2 encoding Cyclin-dependent kinases regulatory subunit 2 is the most upregulated cell cycle regulator when OTUD6A is overexpressed. The results suggest that OTUD6A may serve as a therapeutic target in human cancers.

CKS2 Overexpression Correlates with Prognosis and Immune Cell Infiltration in Lung Adenocarcinoma: A Comprehensive Study based on Bioinformatics and Experiments.

Objective: Cyclin-dependent kinase regulatory subunit 2 (CKS2) plays a vital role in regulation of the cell cycle and cancer progression. However, the role of CKS2 in lung adenocarcinoma (LUAD) remains unkonwn. Here, we examined the prognostic value and biological functions of CKS2 in LUAD by using omics data of 1,235 LUAD samples from TCGA, GEO, and our own cohort as well as data of in vitro experiments.Methods: Kaplan-Meier was conducted to evaluate the prognostic value of CKS2 expression. The association between CKS2 expression level and tumor immune infiltration was explored using the single-sample Gene Set Enrichment Analysis (ssGSEA) and TIMER database. Functional enrichment analyses were performed to annotate the biological functions of CKS2 in LUAD. Furthermore, a series of in vitro experiments and immunohistochemistry were performed for validation.Results: CKS2 overexpression was correlated with the advanced stage, TP53 status, PD-L1 expression, and DNA hypomethylation. Moreover, patients with LUAD and high CKS2 expression exhibited poor overall survival. Functional enrichment analysis indicated that CKS2 was involved in cell division, cell cycle, DNA replication. Experiments in vitro indicated that CKS2 knockdown decreased the invasion and proliferation of LUAD cells and facilitated their apoptosis. ssGSEA and TIMER analysis revealed a negative correlation between CKS2 expression and the immune cell infiltration.Conclusions: In summary, High CKS2 expression was associated with poor prognosis and low levels of infiltrating immune cells in LUAD as well as with malignant phenotypes. Therefore, CKS2 may be a promising prognostic biomarker and therapeutic target in LUAD.

CKS1B as Drug Resistance-Inducing Gene-A Potential Target to Improve Cancer Therapy.

Cancer is a threat to human health and life. Although previously centered on chemical drug treatments, cancer treatment has entered an era of precision targeted therapy. Targeted therapy entails precise guidance, allowing the selective killing of cancer cells and thereby reducing damage to healthy tissues. Therefore, the need to explore potential targets for tumor treatment is vital. Cyclin-dependent kinase regulatory subunit 1B (CKS1B), a member of the conserved cyclin kinase subunit 1 (CKS1) protein family, plays an essential role in cell cycling. A large number of studies have shown that CKS1B is associated with the pathogenesis of many human cancers and closely related to drug resistance. Here, we describe the current understanding of the cellular functions of CKS1B and its underlying mechanisms, summarize a recent study of CKS1B as a target for cancer treatment and discuss the potential of CKS1B as a therapeutic target.

MicroRNA-1258 Inhibits the Proliferation and Migration of Human Colorectal Cancer Cells through Suppressing CKS1B Expression.

Increasing evidence has demonstrated that increased expression of cyclin-dependent kinase regulatory subunit 1B (CKS1B) is associated with the pathogenesis of many human cancers, including colorectal cancer (CRC). However, the regulatory mechanisms underlying the expression of CKS1B in CRC are not completely understood. Here, we investigate the role played by microRNAs in the expression of CKS1B and carcinogenesis in CRC. Among the six microRNAs predicted to target CKS1B gene expression, only miR-1258 was revealed to downregulate CKS1B expression through binding to its 3’-UTR region, as ectopic miR-1258 expression suppressed CKS1B expression and vice versa. In CRC, miR-1258 expression also decreased cell proliferation and migration in vitro and tumor growth in vivo, similar to cells with silenced CKS1B expression. Considering the highly increased levels of CKS1B and decreased expression of miR-1258 in tumors from CRC patients, these findings suggest that miR-1258 may play tumor-suppressive roles by targeting CKS1B expression in CRC. However, the therapeutic significance of these findings should be evaluated in clinical settings.

Cyclin-Dependent Kinase Regulatory Subunit 2 Indicated Poor Prognosis and Facilitated Aggressive Phenotype of Hepatocellular Carcinoma.

Cyclin-dependent kinase regulatory subunit 2 (CKS2) is a member of the cell cycle-dependent protein kinase subunit family, which is implicated as an oncogene in various malignancies. However, the clinical significance, oncogenic functions, and related mechanisms of CKS2 in hepatocellular carcinoma (HCC) remain largely unclear. In the present study, expression features and prognostic value of CKS2 were evaluated in the bioinformatic databases and HCC tissues. The effects of CKS2 on the malignant phenotypes of HCC cells were explored in vitro. According to the analyses of three bioinformatic databases, mRNA levels of CKS2 were elevated in HCC tissues compared with the normal tissues. Immunohistochemical assays found that high CKS2 expression was closely associated with liver cirrhosis (P = 0.019), poor differentiation (P = 0.02), portal vein invasion (P < 0.001), TNM stage (P = 0.019), tumor metastasis (P = 0.008), and recurrence (P = 0.003). The multivariate regression analyses suggested that CKS2 was an independent prognostic factor for overall survival (HR = 2.088, P = 0.014) and disease-free survival (HR = 2.511, P = 0.002) of HCC patients. Moreover, the bioinformatic analyses indicated that CKS2 might be associated with the malignant phenotypes in HCC progression. In addition, in vitro assays showed that CKS2 expression was higher in HCC cell lines than in normal liver cells. Knockdown of CKS2 remarkably repressed the proliferation, colony formation (P = 0.0003), chemoresistance, migration (P = 0.0047), and invasion (P = 0.0012) of HCC cells. Taken together, overexpression of CKS2 was significantly correlated with poor prognosis of HCC patients and the malignant phenotypes of HCC cells, suggesting that it was a novel prognostic biomarker and potential target of HCC.

Downregulation of CKS1B restrains the proliferation, migration, invasion and angiogenesis of retinoblastoma cells through the MEK/ERK signaling pathway.

Retinoblastoma (RB) is a common neoplasm that is exhibited in individuals globally. Increasing evidence demonstrated that cyclin-dependent kinase regulatory subunit 1B (CKS1B) may be involved in the pathogenesis of various tumor types, including multiple myeloma and breast cancer. In the present study, the hypothesis that CKS1B down-regulation would effectively inhibit the proliferation, invasion and angiogenesis of RB cells through the mitogen-activated protein kinase kinase (MEK)/extracellular signal-regulated kinase (ERK) signaling pathway was examined. Initial investigation of the expression profile of CKS1B in RB and adjacent retina tissues was performed using reverse transcription-quantitative polymerase chain reaction and western blot analysis. A total of three RB cell lines, SO-RB50, Y79 and HXO-RB44, were examined for selection of the cell line with the highest expression of CKS1B, and human normal retinal vascular endothelial cells (ACBRI-181) were also evaluated. CKS1B short hairpin RNA (shRNA) sequences (shRNA CKS1B-1, shRNA CKS1B-2 and shRNA CKS1B-3) and negative control shRNA sequences were constructed and transfected into cells at the third generation to evaluate the role of shCKS1B and the MEK/ERK signaling pathway in RB. Furthermore, the effect of shCKS1B on cell proliferation, migration, invasion, apoptosis and angiogenesis was investigated. CKS1B was determined to be highly expressed in RB tissue, compared with adjacent retina tissue. SO-RB50 and HXO-RB44 cells treated with shRNA CKS1B-1 and shRNA CKS1B-2 were selected for the present experiments. Activation of the MEK/ERK signaling pathway increases the expression of MEK, ERK, B-cell lymphoma 2, proliferating cell nuclear antigen, cyclin D1, vascular endothelia growth factor and basic fibroblast growth factor, enhances cell proliferation, migration, invasion and lumen formation, and decreases apoptosis. Following silencing CKS1B, the aforementioned conditions were reversed. The key observations of the present study demonstrated that shCKS1B can inhibit the proliferation, invasion and angiogenesis of RB cells by suppressing the MEK/ERK signaling pathway. Thus, CKS1B represents a potential research target in the development of therapeutics for RB.