Mitosis Gene A-related Kinase Research Articles

In silico analysis unveiling potential biomarkers in gallbladder carcinogenesis

Gallbladder cancer (GBC) is a rare but very aggressive most common digestive tract cancer with a high mortality rate due to delayed diagnosis at the advanced stage. Moreover, GBC progression shows asymptomatic characteristics making it impossible to detect at an early stage. In these circumstances, conventional therapy like surgery, chemotherapy, and radiotherapy becomes refractive. However, few studies reported some molecular markers like KRAS (Kirsten Rat Sarcoma) mutation, upregulation of HER2/neu, EGFR (Epidermal Growth Factor Receptor), and microRNAs in GBC. However, the absence of some specific early diagnostic and prognostic markers is the biggest hurdle for the therapy of GBC to date. The present study has been designed to identify some specific molecular markers for precise diagnosis, and prognosis, for successful treatment of the GBC. By In Silico a network-centric analysis of two microarray datasets; (GSE202479) and (GSE13222) from the Gene Expression Omnibus (GEO) database, shows 50 differentially expressed genes (DEGs) associated with GBC. Further network analysis revealed that 12 genes are highly interconnected based on the highest MCODE (Molecular Complex Detection) value, among all three genes; TRIP13 (Thyroid Receptor Interacting Protein), NEK2 (Never in Mitosis gene-A related Kinase 2), and TPX2 (Targeting Protein for Xklp2) having highest network interaction with transcription factors and miRNA suggesting critically associated with GBC. Further survival analysis data corroborate the association of these genes; TRIP13, NEK2, and TPX2 with GBC. Thus, TRIP13, NEK2, and TPX2 genes are significantly correlated with a greater risk of mortality, transforming them from mere biomarkers of the GBC for early detections and may emerge as prognostic markers for treatment.

Construction and Validation of a Mutation-Related Model in Papillary Renal Cell Carcinoma and Associated Immune Infiltration.

To improve the clinical evaluation of the prognosis of papillary renal cell carcinoma (PRCC), we screened a model to predict the survival of patients with mutations in related genes. We downloaded RNA sequencing information from all patients with PRCC in TCGA. We first analyzed the differences in genes and the enrichment of these differences. Then, by selecting mutant genes, constructing a protein-protein interaction network, least absolute shrinkage and selection operator regression, and multivariable Cox regression, a prognosis model was constructed. Additionally, the model was validated using external data sets. We analyzed the immune infiltration of PRCC and the correlation between the model and popular targets. Finally, we performed tissue microarray analysis and immunohistochemistry to verify the expression levels of the three genes. We constructed a three-gene (never in mitosis gene A-related kinase 2 [NEK2], centromere protein A [CENPA], and GINS complex subunit 2 [GINS2]) model. The verification results indicated that the model had a good prediction effect. We also developed a visual nomogram. Enrichment analysis revealed the major pathways involved in muscle system processes. Immunoassays showed that the expression level of CENPA was positively correlated with PD-1 and CTLA4 expression levels. Immunohistochemical and tissue microarray results showed that these three genes were highly expressed in PRCC, which was consistent with the predicted results in the database. We constructed and verified a three-gene model to predict the patient survival. The results show that the model has a good prediction effect.

Prognostic value and therapeutic potential of NEK family in stomach adenocarcinoma.

Never in mitosis gene A-related kinase (NEK) is an 11-membered family of serine/threonine kinases (NEK1-NEK11), which are known to play important roles in the formation and development of cancer. However, few studies have examined the roles of these kinases in the development of stomach adenocarcinoma (STAD). In this study, we conducted a comprehensive analysis of the relationships between the NEKs family members and STAD. The differential expression of the NEK genes in STAD was validated using The Cancer Genome Atlas (TCGA) and Tumor Immune Estimation Resource (TIMER) databases, and their prognostic and diagnostic values of NEKs in STAD were assessed using the Kaplan-Meier plotter and TCGA data. The effect of NEK expression on immune cell infiltration in STAD was analysed using the TIMER and TISIDB databases. The expression levels of the majority of the NEK family members were consistently upregulated in STAD, whereas that of NEK10 was downregulated. The upregulation of NEK2/3/4/5/6/8 was closely associated with clinicopathological parameters of patients, and the overexpressed levels of these proteins had good diagnostic value for the disease. NEK1/8/9/10/11 expression correlated with poor overall survival and post-progressive survival, whereas a higher NEK1/6/9/11 level implied worse first progressive survival. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses revealed that the NEKs may be related to immunological responses. Additionally, our study confirmed that these kinases correlated with immune cell infiltration and different immune infiltration subtypes in STAD. Our results suggest that NEK9 in particular has the potential to be used as a diagnostic and prognostic biomarker of STAD development and progression and an immune target for treatment of the disease. These findings expand our understanding of the biological functions of the NEK family members in STAD.

Behavior of intracellular lipid droplets during cell division in HuH7 hepatoma cells

Intracellular lipid droplets (LDs) are ubiquitous organelles found in many cell types. During mitosis, membranous organelles, including mitochondria, are divided into small pieces and transferred to daughter cells; however, the process of LD transfer to daughter cells is not fully elucidated. Herein, we investigated the behavior of LDs during mitosis in HuH7 human hepatoma cells. While fragments of the Golgi apparatus were scattered in the cytosol during mitosis, intracellular LDs retained their size and spherical morphology as they translocated to the two daughter cells. LDs were initially distributed throughout the cell during prophase but positioned outside the spindle in metaphase, aligning at the far sides of the centrioles. A similar distribution of LDs during mitosis was observed in another hepatocarcinoma HepG2 cells. When the spindle was disrupted by nocodazole treatment or never in mitosis gene A-related kinase 2A knockdown, LDs were localized in the area outside the chromosomes, suggesting that spindle formation is not necessary for LD localization at metaphase. The amount of major LD protein perilipin 2 reduced while LDs were enriched in perilipin 3 during mitosis, indicating the potential alteration of LD protein composition. Conclusively, the behavior of LDs during mitosis is distinct from that of other organelles in hepatocytes.

NEK2 promotes esophageal squamous cell carcinoma cell proliferation, migration and invasion through the Wnt/β-catenin signaling pathway

ObjectivesThe NEK2 (never in mitosis gene A-related kinase 2), a serine/threonine kinase involved in chromosome instability and tumorigenesis. Hence, this study aimed to explore the molecular function of NEK2 in esophageal squamous cell carcinoma (ESCC).MethodsBy available transcriptome datasets (GSE53625 cohort, GSE38129 cohort, and GSE21293 cohort), we analyzed the differentially expressed genes in invading and non-invading ESCC. Subsequently, we evaluated the association between NEK2 expression level and clinical outcomes through Kaplan–Meier analysis method. The quantitative real-time polymerase chain reaction (qRT-PCR) and western blotting (WB) analyses were performed to determine the expression levels of NEK2 mRNA and protein, respectively. We knocked down the NEK2 expression in ESCC cells (ECA109 and TE1), and evaluated the NEK2 biology function associated with ESCC cell proliferation, migration, invasion, and colony formation abilities. Finally, the downstream pathway of NEK2 was analyzed through Gene Set Enrichment Analysis (GSEA) and validated the regulatory mechanism of NEK2 on the potential pathway through WB.ResultsWe found that NEK2 was highly expressed in ESCC cells compared with human esophageal epithelial cells (HEEC) (P < 0.0001), and high NEK2 expression was remarkably associated with poor survival (P = 0.019). Knockdown of NEK2 showed the significant inhibitory effect for tumorigenesis, and suppressed the ESCC cells proliferation, migration, invasion, and formation of colonies abilities. Additionally, GSEA revealed that Wnt/β-catenin pathway was a downstream pathway of NEK2. WB results further validated the regulatory mechanism of NEK2 for Wnt/β-catenin signaling.ConclusionsOur results indicated that NEK2 promotes ESCC cell proliferation, migration and invasion by activating the Wnt/β-catenin pathway. NEK2 could be a promising target for ESCC.

Oridonin employs interleukin 1 receptor type 2 to treat noise-induced hearing loss by blocking inner ear inflammation

NOD-like receptor protein 3 (NLRP3) inflammasomes trigger the inflammatory cascades and participate in various inflammatory diseases, including noise-induced hearing loss (NIHL) caused by oxidative stress. Recently, the anti-inflammatory traditional medicine oridonin (Ori) has been reported to provide hearing protection in mice after noise exposure by blocking the NLRP3-never in mitosis gene A-related kinase 7 (NEK7)-inflammasome complex assembly. Using RNA sequencing analysis, we further elucidated that interleukin 1 receptor type 2 (IL1R2) may be another crucial factor regulated by Ori to protect NIHL. We observed that IL1R2 expression was localized in spiral ganglion neurons, inner and outer hair cells, in Ori-treated mouse cochleae. Additionally, we confirmed that ectopic overexpression of IL1R2 in the inner ears of healthy mice using an adeno-associated virus delivery system significantly reduced noise-induced ribbon synapse lesions and hearing loss by blocking the “cytokine storm” in the inner ear. This study provides a novel theoretical foundation for guiding the clinical treatment of NIHL.

A Comparative Analysis of the Gene Expression Profiles of Small Cell Esophageal Carcinoma, Small Cell Lung Cancer, and Esophageal Adeno/Squamous Carcinoma

Purpose/objectives: Primary small cell esophageal carcinoma (SCEC) is a rare malignancy without an established treatment strategy. This study investigated the gene expression profile of SCEC and compared it with the expression profiles of small cell lung cancer (SCLC) and esophageal adeno/squamous carcinoma (EAC/ESCC).Materials/methods: All patients with SCEC, SCLC, and EAC/ESCC in the Surveillance, Epidemiology, and End Results (SEER) database 1973–2014 were included. Overall survival (OS) and prognostic analysis were conducted. De novo expression array analysis was performed on three pairs of frozen primary SCEC tissues and the corresponding normal samples from the institutional tissue bank using the Affymetrix HG U133 plus 2.0 Array. These data were complemented with public domain expression data sets from the Gene Expression Omnibus (GEO) repository using the same working platforms, which included primary SCLC, EAC/ESCC, and normal lung/esophagus specimens (series GSE30219 and GSE26886). After individual normalization, the primary tumors were submitted to statistical analysis (GeneSpring GX 13.0) to identify the differentially expressed genes (DEGs) relative to their paired normal tissues. Enrichments of genes categorized by function and gene interactions were analyzed by DAVID 6.8 and STRING 11.0, respectively.Results: The clinical outcomes of the patients with SCEC were significantly more worse than those with EAC/ESCC and SCLC in the SEER database. SCEC had more DEGs in common with SCLC than EAC/ESCC [829 vs. 450; false discovery rate (FDR) < 0.01; and fold change ≥2], leading to a stronger correlation between SCEC and SCLC (Pearson's correlation coefficient was 0.60 for SCEC vs. SCLC, 0.51 or 0.45 for SCEC vs. ESCC or EAC, and the coefficient was 0.73 for ESCC vs. EAC). Similar findings were obtained by principal component analysis (PCA) using all DEGs retrieved from these four groups. Functional annotation showed that a higher proportion of pathways and biological processes were common between SCEC and SCLC and were associated with the cell cycle (mitosis), DNA replication, telomere maintenance, DNA repair, and P53 and RB pathways (Benjamini p < 0.05). Compared with EAC/ESCC, SCEC shared more co-upregulated DEGs coding for the aforementioned common pathways with SCLC (584 vs. 155). In addition, SCEC and SCLC were found to have possessed overlapping gene-interactive networks, with centromere protein F (CENPF), never in mitosis gene A-related kinase 2 (NEK2), kinesin family member 11 (KIF11), thymopoietin (TMPO), and forkhead box protein M1 (FOXM1) as common skeletons centered by gene regulatory network (NUF2).Conclusions: This study is the first attempt to examine the genomic signatures of SCEC at the transcriptomic level and compare the expression profiles between SCEC, SCLC, and EAC/ESCC. Our preliminary data indicate that SCEC and SCLC display notably similar patterns of gene expression for mitosis and DNA repair. Further validation studies are warranted.

NEK2 inhibition triggers anti-pancreatic cancer immunity by targeting PD-L1

Despite the substantial impact of post-translational modifications on programmed cell death 1 ligand 1 (PD-L1), its importance in therapeutic resistance in pancreatic cancer remains poorly defined. Here, we demonstrate that never in mitosis gene A-related kinase 2 (NEK2) phosphorylates PD-L1 to maintain its stability, causing PD-L1-targeted pancreatic cancer immunotherapy to have poor efficacy. We identify NEK2 as a prognostic factor in immunologically “hot” pancreatic cancer, involved in the onset and development of pancreatic tumors in an immune-dependent manner. NEK2 deficiency results in the suppression of PD-L1 expression and enhancement of lymphocyte infiltration. A NEK binding motif (F/LXXS/T) is identified in the glycosylation-rich region of PD-L1. NEK2 interacts with PD-L1, phosphorylating the T194/T210 residues and preventing ubiquitin-proteasome pathway-mediated degradation of PD-L1 in ER lumen. NEK2 inhibition thereby sensitizes PD-L1 blockade, synergically enhancing the anti-pancreatic cancer immune response. Together, the present study proposes a promising strategy for improving the effectiveness of pancreatic cancer immunotherapy.

Study of mangal based naphthoquinone derivatives anticancer potential towards chemo-resistance related Never in mitosis gene A-related kinase 2-Insilico approach

ABSTRACT Never in mitosis gene A-related kinase 2 (NEK2) is a member of serine-threonine kinase mainly involved in cell cycle process. Clinical studies revealed that NEK2 overexpression in many tumour types, also reported for their association with genetic abnormalities like mitotic machinery deregulation and chromosomal instability. Besides NEK2 plays a key role in maintaining the transmuted phenotype of tumour cells and induction of chemo-resistance in tumour types. Our studies involved NEK2 transcriptional profile search, screening of druggable cavities in NEK2, Drug likeliness of mangrove derived naphthoquinone derivatives avicennone, avicennone A, avicennone B, avicennone C, avicennone D, avicenone E, avicennone F and avicennone G, avicequinone A, stenocarpoquinone B, avicequinone C, avicenol A, avicenol C, brugine, apigenin, chrysin and molecular docking studies to assess compounds binding efficacy towards NEK2. Irreversible inhibitors have several advantages over noncovalent inhibitors, comprising sustained pharmacodynamics with high potency practical application, and specificity. Thus Targeting the cysteine 22 (Cys-22) residue near the catalytic site of NEK2 kinase will result in irreversible inhibition. Avicenol A, Avicennone G, Chrysin and Brugine formed the irreversible covalent binding with NEK2 through Cys 22, thus they can be considered as potential kinase inhibitors with limited off-target response. But proposed compounds need to be tested further through in vitro and in vivo studies to propose as potent NEK2 inhibitors.

Overexpression of NEK2 is correlated with poor prognosis in human clear cell renal cell carcinoma.

Objectives: Never in mitosis gene A-related kinase 2 (NEK2) has been implicated in tumorigenesis in various tissues, but its function in clear cell renal cell carcinoma (ccRCC) tumorigenesis is unclear. We evaluated the correlation between NEK2 expression and ccRCC. Methods: Immunohistochemistry analysis of NEK2 protein was done on high-density multi-organ Human Cancer tissue microarray derived from the patient samples from clear cell renal cell carcinoma. We used multiple clinical cohorts to analyze the NEK2 immunohistochemical staining expression across human cancers. The cancer genome atlas (TCGA) data analysis of NEK2 was done through UALCAN web servers. Association of NEK2 and Kaplan–Meier survival analysis was done on both of our clinical database and available TCGA datasets. Results: Using the UALCAN cancer transcriptional data analysis website, we found that NEK2 is overexpressed in ccRCC, and its expression was associated with overall survival. According to the analyses of our own clinical database and immunohistochemical staining, protein levels of NEK2 were elevated in renal carcinoma compared to adjacent normal tissues. Kaplan–Meier survival analysis of both UALCAN and our database showed that high expression of NEK2 was associated with a poor prognosis. Multivariate and univariate analyses showed that NEK2 expression was closely related to a poor prognosis. The findings suggest that NEK2 is associated with ccRCC. Conclusion: These studies show that NEK2 is over-expressed in clear cell renal cell carcinoma and plays an essential role in cancer cell survival, as such NEK2 could serve as a novel potential target for therapeutic intervention in ccRCC.

High expression of NEK2 promotes gastric cancer progression via activating AKT signaling.

Never in mitosis gene A-related kinase 2 (NEK2) has been recognized as an oncogene involved in the initiation and progression of various human cancers. However, our knowledge is still lacking in regard to the function of NEK2 in gastric cancer, the most common cancer in Eastern Asia associated with poor prognosis. Therefore, in the present study, we investigated the association of NEK2 with gastric cancer. We found that the development of gastric cancer is associated with NEK2 overexpression, particularly in patients with large tumor size and lymph node metastasis. We also provided evidence that NEK2 overexpression binds to and inhibits protein phosphatase 1 (PP1), which subsequently activates AKT and the downstream oncogenic pathways. As a result, via AKT/HIF1α axis, the glucose metabolism is reprogrammed towards aerobic glycolysis to provide rapid energy for the growth of gastric cancer cells. Moreover, the autophagic activity is suppressed via AKT/mTOR axis, leading to impaired response to cancer treatment and enhanced cell survival. In contrast, inactivating AKT by NEK2 silencing decreases aerobic glycolysis and promotes autophagic cell death, which eventually inhibits the growth of gastric cancer cell. All these results revealed that NEK2 promotes gastric cancer progression via activating AKT-mediated signaling pathways, which expanded our knowledge on gastric cancer pathogenesis and also provided novel target for clinical treatment.

High expression of NEK2 promotes lung cancer progression and drug resistance and is regulated by mutant EGFR.

Activating mutations within the tyrosine kinase (TK) domain of epidermal growth factor receptor (EGFR) gene are observed in 10 ~ 30% of the patients diagnosed with non-small cell lung cancer (NSCLC), and are causally related to NSCLC initiation and progression. Treatments with tyrosine kinase inhibitors (TKIs) targeting EGFR significantly improve the outcome of NSCLC patients with EGFR mutation, but are often associated with drug resistance, which is the main cause of treatment failure and cancer relapse. In the present study, by screening the transcriptome of NSCLC patients, we found that EGFR activation is highly correlated with the up-regulation of mitotic regulator, never in mitosis gene A-related kinase 2 (NEK2). NEK2 overexpression is associated with the poor survival of EGFR-mutant patients but not the wild-type patients. Further functional validation revealed that EGFR mutation induces NEK2 expression by activating ERK signaling pathway. Elevated NEK2 level promotes the rapid cell cycle progression and favors the rapid proliferation of EGFR-mutant NSCLC cells. Of note, NEK2 overexpression also impairs the efficacy of TKI treatment via inhibiting apoptosis, while depleting NEK2 suppresses cell growth and restored the sensitivity of TKI in NSCLC cells. Taken together, our study revealed that NEK2 is an oncogene regulated by EGFR mutation and is involved in disease progression and treatment response in NSCLC with EGFR mutation. These findings will pave the road for optimizing personalized treatment strategies to overcome drug resistance and improve the prognosis of lung cancer patients with EGFR mutation.

NEK2 Is an Effective Target for Cancer Therapy With Potential to Induce Regression of Multiple Human Malignancies.

Cancer is characterized by uncontrolled cell proliferation due to the aberrant activity of various proteins. Cell cycle-related proteins are thought to be important in several functions, such as proliferation, invasion and drug resistance in human malignancies. Never in mitosis gene A-related kinase 2 (NEK2) is a cell cycle-related protein. NEK2 is highly expressed in various tumor types and cancer cell lines. NEK2 expression is correlated with rapid relapse and poor outcome in multiple cancer types. Several researchers have demonstrated that NEK2 inhibition results in anticancer effects against many types of cancers, both in vitro and in vivo. Recent research strongly indicates the advantages of NEK2-targeted therapy for cancer. This review focuses on the current understanding of NEK2 in cancer and the rationale of a xenograft cancer model for cancer treatment. A possible therapeutic strategy, such as inhibitor and nucleic acid medicine targeting of NEK2, is also discussed.

NEK3-mediated SNAP29 phosphorylation modulates its membrane association and SNARE fusion dependent processes

Intracellular membrane fusion depends on the presence of specific mediators, the vesicle (v-) and the target (t-) SNAREs (Soluble N-ethylmaleimide-sensitive factor, NSF, attachment protein SNAP receptors), whose interaction brings apposing membranes to close proximity and initiates their fusion. SNAP29 (synaptosomal-associated protein 29), a t-SNARE protein, is involved in multiple fusion events during intracellular transport and affects structure of organelles such as the Golgi apparatus and focal adhesions. Mutations in SNAP29 gene result in CEDNIK (Cerebral dysgenesis, neuropathy, ichthyosis and palmoplantar keratoderma) syndrome. In the present study, we show that NEK3 (NIMA-never in mitosis gene A-related kinase 3)-mediated serine 105 (S105) phosphorylation of SNAP29 directs its membrane association, without which cells present defective focal adhesion formation, impaired Golgi structure and attenuated cellular recycling. In contrast to a phosphorylation-defective serine 105 to alanine (S105A) mutant, wildtype SNAP29, partially rescued the abnormal morphology of a CEDNIK patient derived fibroblasts. Our results highlight the importance of NEK3-mediated S105 phosphorylation of SNAP29 for its membrane localization and for membrane fusion dependent processes.

Recessive NEK9 mutation causes a lethal skeletal dysplasia with evidence of cell cycle and ciliary defects.

Skeletal dysplasias are a clinically and genetically heterogeneous group of bone and cartilage disorders. Whilst >450 skeletal dysplasias have been reported, 30% are genetically uncharacterized. We report two Irish Traveller families with a previously undescribed lethal skeletal dysplasia characterized by fetal akinesia, shortening of all long bones, multiple contractures, rib anomalies, thoracic dysplasia, pulmonary hypoplasia and protruding abdomen. Single nucleotide polymorphism homozygosity mapping and whole exome sequencing identified a novel homozygous stop-gain mutation in NEK9 (c.1489C>T; p.Arg497*) as the cause of this disorder. NEK9 encodes a never in mitosis gene A-related kinase involved in regulating spindle organization, chromosome alignment, cytokinesis and cell cycle progression. This is the first disorder to be associated with NEK9 in humans. Analysis of NEK9 protein expression and localization in patient fibroblasts showed complete loss of full-length NEK9 (107 kDa). Functional characterization of patient fibroblasts showed a significant reduction in cell proliferation and a delay in cell cycle progression. We also provide evidence to support possible ciliary associations for NEK9. Firstly, patient fibroblasts displayed a significant reduction in cilia number and length. Secondly, we show that the NEK9 orthologue in Caenorhabditis elegans, nekl-1, is almost exclusively expressed in a subset of ciliated cells, a strong indicator of cilia-related functions. In summary, we report the clinical and molecular characterization of a lethal skeletal dysplasia caused by NEK9 mutation and suggest that this disorder may represent a novel ciliopathy.

Never in mitosis gene A-related kinase 6 and aurora kinase A: New gene biomarkers in the conversion from ulcerative colitis to colorectal cancer.

Ulcerative colitis (UC) is an important risk factor for colorectal cancer (CRC). Histone modifications are one of the epigenetic mechanisms that may have key roles in the carcinogenesis of CRC. At present, there are no studies comparing histone modification patterns of UC and CRC in the literature. Therefore the aim of the present study was to investigate whether genes, particularly those involved in histone modification, have value in patient monitoring with regards to CRC development in UC. Key gene expressions of the histone modification enzyme were assessed and compared in CRC, UC and control groups using the RT-PCR array technique. Patients were divided into subgroups based on the extent and duration of the disease and inflammatory burden, which are considered risk factors for CRC development in UC patients. In UC and CRC groups, a significantly higher overexpression of the NEK6 and AURKA genes compared to the control group was identified. In addition, there was a significantly higher overexpression of HDAC1 and PAK1 genes in the UC group, and of HDAC1, HDAC7, PAK1 and AURKB genes in the CRC group. NEK6, AURKA, HDAC1 and PAK1 were significantly overexpressed in patients with a longer UC duration. Overexpression of AURKA and NEK6 genes was significantly more pronounced in UC patients with more extensive colon involvement. HDAC1, HDAC7, PAK1, NEK6, AURKA and AURKB are important diagnostic and prognostic markers involved in the carcinogenesis of CRC. HDAC1, PAK1, NEK6 and AURKA may be considered as diagnostic markers to be used in CRC screening for UC patients.

Never in mitosis gene A-related kinase 6 promotes cell proliferation of hepatocellular carcinoma via cyclin B modulation.

Never in mitosis gene A-related kinase (Nek) 6 is a recently identified Nek that is required for mitotic cell cycle progression; however, the role and mechanism of Nek6 activity during hepatocarcinogenesis is not well known. The aim of this study was to investigate the potential roles and internal mechanism of Nek6 in hepatocellular carcinoma (HCC) development. In the present study, Nek6 was found to be overexpressed in HCC samples and cell lines by florescent real-time quantitative polymerase chain reaction, immunohistochemistry and western blot analysis. Furthermore, it was evidenced to contribute to oncogenesis and progression. The ectopic overexpression of Nek6 promoted cell proliferation and colony formation, whereas gene silencing of Nek6 inhibited these phenotypes, as documented in Huh7, PLC/PRF/5, Hep3B and HepG2 HCC cell lines. Mechanistic analyses indicated that Nek6 regulates the transcription of cyclin B through cdc2 activation, and promotes the accumulation of G0/G1-phase cells. In conclusion, the findings of the current study suggested that Nek6 contributes to the oncogenic potential of HCC, and may present as a potential therapeutic target in this disease.

Aurora kinase A (AURKA) and never in mitosis gene A-related kinase 6 (NEK6) genes are upregulated in erosive esophagitis and esophageal adenocarcinoma

Gastroesophageal reflux disease is a risk factor for esophageal adenocarcinoma yet studies that have investigated the relationship between erosive esophagitis and esophageal adenocarcinoma have usually focused on symptom-related evidence or polymorphisms. There are no epigenetic gene expression studies on this topic. In this study, we aimed to evaluate the relationship between erosive esophagitis and esophageal adenocarcinoma to identify whether there is a genetic predisposition for esophageal adenocarcinoma. The Human Epigenetic Chromatin Modification Enzyme RT(2) Profiler(™) PCR array (PAHS-085A) was used to detect the expression of 84 key genes encoding enzymes. This was carried out prospectively for samples from 60 patients (20 patients as a control group, 20 patients with erosive esophagitis and 20 patients with esophageal adenocarcinoma). AURKA, AURKB, NEK6 were expressed at significantly higher levels in esophageal adenocarcinoma compared to the control group. MBD2 was expressed at significantly lower levels in the esophageal adenocarcinoma group compared to the control group. AURKA, AURKC, HDAC9 and NEK6 were expressed at significantly higher levels in erosive esophagitis compared to the control group. There was no difference in upregulated gene expression between the erosive esophagitis and esophageal adenocarcinoma. MBD2 was significantly downregulated in esophageal adenocarcinoma compared to erosive esophagitis. NEK6 and AURKA were significantly upregulated in esophageal adenocarcinoma and erosive esophagitis compared to the control group. This is a novel study on the genetic predisposition for erosive esophagitis and esophageal adenocarcinoma. AURKA and NEK6 are two promising genetic markers for erosive esophagitis and esophageal adenocarcinoma.

Clinical and Biological Significance of Never in Mitosis Gene A-Related Kinase 6 (NEK6) Expression in Hepatic Cell Cancer

Nek6 is a cell cycle regulatory gene, which can control cell proliferation and survival. Recent studies suggested that desregulation of Nek6 expression plays a key role in oncogenesis. This study was aimed to investigate the potential roles of Nek6 in hepatocellular carcinoma (HCC) development. Immunohistochemistry and Western blot analysis was performed for Nek6 in 80 hepatocellular carcinoma samples. The data were correlated with clinicopathological features. The univariate and multivariate survival analyses were performed to determine the prognostic significance of Nek6 in HCC. In addition, Nek6 expression vector was used to detect its role in cell cycle control. Nek6 was overexpressed in hepatocellular carcinoma as compared with the adjacent normal tissue. High expression of Nek6 was associated with histological grade and the level of alpha fetal protein, and Nek6 was positively correlated with proliferation marker Ki-67. Univariate analysis showed that Nek6 expression was associated with poor prognosis. Multivariate analysis indicated that Nek6 and Ki-67 protein expression was an independent prognostic marker for HCC. While in vitro, following release from serum starvation of HuH7 HCC cell, the expression of Nek6 was upregulated. Overexpression Nek6 in Huh7 cell could promote the cell cycle. In conclusion, Nek6 is involved in the pathogenesis of hepatocellular carcinoma. It may be a favorable independent poor prognostic parameter for hepatocellular carcinoma.

Benzimidazole Inhibitors Induce a DFG-Out Conformation of Never in Mitosis Gene A-Related Kinase 2 (Nek2) without Binding to the Back Pocket and Reveal a Nonlinear Structure−Activity Relationship

We describe herein the structure-activity relationship (SAR) and cocrystal structures of a series of Nek2 inhibitors derived from the published polo-like kinase 1 (Plk1) inhibitor (R)-1. Our studies reveal a nonlinear SAR for Nek2 and our cocrystal structures show that compounds in this series bind to a DFG-out conformation of Nek2 without extending into the enlarged back pocket commonly found in this conformation. These observations were further investigated, and structure-based design led to Nek2 inhibitors derived from (R)-1 with more than a hundred-fold selectivity against Plk1.