Dynamic expression of the vertebrate-specific protein Nucks during rodent embryonic development

Acts as a Promising Novel Biomarker for the Prognosis of Patients with Hepatocellular Carcinoma

Objective: Nuclear casein kinase and cyclin-dependent kinase substrate 1 (NUCKS1) is highly expressed in some tumors, including hepatocellular carcinoma (HCC). However, its clinical significance in HCC prognosis is still unclear. The aim of this study was to explore the expression and prognostic value of NUCKS1 in HCC. Materials and Methods: Quantitative real-time polymerase chain reaction was used to detect relative expression of NUCKS1 mRNA in HCC tissues and corresponding adjacent normal tissues. The relationship between NUCKS1 expression and clinical characteristics of patients was analyzed by χ2 test. Kaplan-Meier method and Cox regression analysis were applied to estimate prognostic value of NUCKS1 in HCC. Results: Compared with normal ones, the expression of NUCKS1 mRNA was significantly upregulated in HCC tissues (p < 0.001). Besides, NUCKS1 expression was closely associated with tumor differentiation, tumor node metastasis stage, vascular invasion, and metastasis (p < 0.05). Kaplan-Meier analysis revealed that overall survival was obviously longer in HCC patients with low expression of NUCKS1 than those with high NUCKS1 expression (log rank test, p = 0.001). NUCKS1 might be an independent prognostic factor for HCC patients (HR = 1.905, 95% CI = 1.106-3.283, p = 0.020). Conclusions: NUCKS1 may be correlated with the progression of HCC and serve as a potential predictive factor for the prognosis of this disease.

Construction of a miRNA-mRNA network related to exosomes in metastatic hepatocellular carcinoma

Aims

This study aimed to construct a miRNA-mRNA network to elucidate the molecular mechanism of exosome function in metastatic HCC.

Methods

We explored the Gene Expression Omnibus (GEO) database and then analyzed the RNAs of 50 samples to obtain differentially expressed miRNAs (DEMs) and mRNAs (DEGs) involved in the progression of metastatic HCC. Next, a miRNA-mRNA network related to exosomes in metastatic HCC was constructed on the basis of the identified DEMs and DEGs. Finally, the function of the miRNA-mRNA network was explored by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis. Immunohistochemistry was performed to validate expression of NUCKS1 in HCC specimens. Based on the immunohistochemistry, the score of the NUCKS1 expression was calculated, and the patients were divided into high- and low-expression patients, and the differences in survival between the two groups were compared.

Results

Through our analysis, 149 DEMs and 60 DEGs were identified. In addition, a miRNA-mRNA network, including 23 miRNAs and 14 mRNAs, was constructed. Low expression of NUCKS1 was validated in the majority of HCCs compared with their matched adjacent cirrhosis specimens (P < 0.001), which was consistent with our result of differential expression analyses. HCC patients with low expression of NUCKS1 had shorter overall survival than those with high NUCKS1 expression (P = 0.0441).

Conclusions

The novel miRNA-mRNA network will provide new insights into the underlying molecular mechanisms of exosomes in metastatic HCC. NUCKS1 might serve a potential therapeutic target to restrain the development of HCC.

NUCKS1 is a highly modified, chromatin-associated protein involved in a diverse set of biological and pathophysiological processes

The Nuclear Casein and Cyclin-dependent Kinase Substrate 1 (NUCKS1) protein is highly conserved in vertebrates, predominantly localized to the nucleus and one of the most heavily modified proteins in the human proteome. NUCKS1 expression is high in stem cells and the brain, developmentally regulated in mice and associated with several diverse malignancies in humans, including cancer, metabolic syndrome and Parkinson's disease. NUCKS1 function has been linked to modulating chromatin architecture and transcription, DNA repair and cell cycle regulation. In this review, we summarize and discuss the published information on NUCKS1 and highlight the questions that remain to be addressed to better understand the complex biology of this multifaceted protein.

Nucks1 gene polymorphism rs823114 is associated with the positive symptoms and neurocognitive function of patients with schizophrenia in parts of southern China

Nuclear casein kinase and cyclin-dependent kinase substrate 1 (nucks1) are considered a potential susceptibility gene for certain neurological diseases, such as Parkinson's disease (PD). In our study, we genotyped three single nucleotide polymorphisms (SNPs) (rs4951261, rs823114 and rs951366) of the nucks1 gene in 774 schizophrenic patients and 819 healthy controls using the improved multiplex ligation detection reaction (imLDR) technique. Furthermore, we also studied the relationship between the above SNPs and the clinical psychiatric symptoms and neurocognitive function of the patients. Genotype distributions and allele frequencies of these SNPs showed no significant differences and were found between patients and healthy controls. However, in an analysis of the positive symptom score of rs823114 among male patients, we found that the score of the A/A genotype was lower than that of the G/A+G/G genotypes (P = 0.001, P(corr) = 0.003]. Additionally, we also found that among the female patients, G allele carriers with rs823114 had lower semantic fluency scores than subjects with the A/A genotype (P = 0.010, P(corr) = 0.030]. Our data show for the first time that rs823114 polymorphism of nucks1 may affect positive symptoms and neurocognitive function in patients with schizophrenia in parts of southern China.

Upregulation of NUCKS1 in Lung Adenocarcinoma is Associated with a Poor Prognosis

To evaluate the clinicopathologic features and survival analysis of NUCKS1 expression in human lung adenocarcinoma (LA), we used bioinformatic methods to obtain NUCKS1 gene status and correlated it with prognosis in LA. We compared NUCKS1 expression in 70 samples of LA with intrinsically normal lung alveoli (NLA) by immunohistochemistry, and analyzed their clinicopathologic features. NUCKS1 was overexpressed in LA components(LACs) relative to NLA, and was significantly correlated to patient with 5-year disease-free survival (DFS) and overall survival(OS). Elevated NUCKS1 expression in LACs was shown to be an independent prognostic indicator for OS and a biomarker in LA.

Roles of NUCKS1 in Diseases: Susceptibility, Potential Biomarker, and Regulatory Mechanisms

Nuclear casein kinase and cyclin-dependent kinase substrate 1 (NUCKS1) is a 27 kD chromosomal, highly conserved, and vertebrate-specific protein. NUCKS1 gene encodes a nuclear protein and the conserved regions of NUCKS1 contain several consensus phosphorylation sites for casein kinase II (CK2) and cyclin-dependent kinases (Cdk) and a basic DNA-binding domain. NUCKS1 is similar to the high mobility group (HMG) family which dominates chromatin remodeling and regulates gene transcription. Meanwhile, NUCKS1 is a RAD51 associated protein 1 (RAD51AP1) paralog that is significant for homologous recombination (HR) and genome stability and also a transcriptional regulator of the insulin signaling components. NUCKS1 plays an important role in DNA damage response and metabolism, participates in inflammatory immune response, and correlates with microRNA. Although there is still not enough functional information on NUCKS1, evidences suggest that NUCKS1 can be used as the biomarker of several cancers. This review summarizes the latest research on NUCKS1 about its susceptibility in diseases, expression levels, and regulatory mechanisms as well as the possible functions in reference to diseases.

NUCKS nuclear elevated expression indicates progression and prognosis of ovarian cancer

NUCKS (nuclear, casein kinase, and cyclin-dependent kinase substrate) is implicated in the tumorigenesis of several human malignancies, but its role in ovarian cancer remains unknown. We aim to investigate NUCKS expression and its clinical significance in ovarian cancer. The messenger RNA expression of NUCKS was determined in normal and malignant ovarian tissues using quantitative polymerase chain reaction assay. Immunohistochemistry was applied to detect the status of NUCKS protein expression in 121 ovarian cancer tissues. NUCKS protein high expression was detected in 52 (43.0%) of 121 patients. NUCKS messenger RNA expression was gradually upregulated in non-metastatic ovarian cancers ( n = 20), metastatic ovarian cancers ( n = 20), and its matched metastatic lesions ( n = 20) in comparison with that in normal ovarian tissues ( n = 10; p < 0.05). Elevated expression of NUCKS in ovarian cancer was associated significantly with the Federation of Gynecology and Obstetrics stage ( p = 0.037), histological grade ( p = 0.003), residual disease ( p = 0.013), lymph node metastasis ( p = 0.002), response to chemotherapy ( p < 0.001), and recurrence ( p = 0.013). In the multivariate Cox analysis, NUCKS expression was an independent prognostic marker for overall survival and disease-free survival in ovarian cancer with p values of <0.001 for both. Especially, NUCKS overexpression had prognostic potential for overall survival and disease-free survival ( p < 0.001 for both) in advanced ovarian cancers and only for disease-free survival in early ovarian cancers ( p = 0.017). Our data suggest that NUCKS overexpression may contribute to progression and poor prognosis in ovarian cancer especially in advanced ovarian cancer.

Identification of kinases phosphorylating 13 sites in the nuclear, DNA-binding protein NUCKS

NUCKS is a vertebrate specific, nuclear and DNA-binding phospho protein. The protein is highly expressed in rapidly dividing cells, and is overexpressed in a number of cancer tissues. The phosphorylation of NUCKS is cell cycle and DNA-damage regulated, but little is known about the responsible kinases. By utilizing in vitro and in vivo phosphorylation assays using isolated NUCKS as well as synthetic NUCKS-derived peptides in combination with mass spectrometry, phosphopeptide mapping, phosphphoamino acid analyses, phosphospecific antibodies and the use of specific kinase inhibitors, we found that NUCKS is phosphorylated on 11 sites by CK2. At least 7 of the CK2 sites are phosphorylated in vivo. We also found that NUCKS is phosphorylated on two sites by ATM kinase and DNA-PK in vitro, and is phosphorylated in vivo by ATM kinase in γ-irradiated cells. All together, we identified three kinases phosphorylating 13 out of 39 in vivo phosphorylated sites in mammalian NUCKS. The identification of CK2 and PIKK kinases as kinases phosphorylating NUCKS in vivo provide further evidence for the involvement of NUCKS in cell cycle control and DNA repair.

NUCKS: a potential biomarker in cancer and metabolic disease

Nuclear, casein kinase and cyclin-dependent kinase substrate (NUCKS), a protein similar to the HMG (high-mobility group) protein family, is one of the most modified proteins in the mammalian proteome. Although very little is known about the biological roles of NUCKS, emerging clinical evidence suggests that this protein can be a biomarker and therapeutic target in various human ailments, including several types of cancer. An inverse correlation between NUCKS protein levels and body mass index in humans has also been observed. Depletion of NUCKS in mice has been reported to lead to obesity and impaired glucose homoeostasis. Genome-wide genomic and proteomic approaches have revealed that NUCKS is a chromatin regulator that affects transcription. The time is now ripe for further understanding of the role of this novel biomarker of cancer and the metabolic syndrome, and how its sundry modifications can affect its function. Such studies could reveal how NUCKS could be a link between physiological cues and human ailments.

NUCKS1 overexpression is a novel biomarker for recurrence-free survival in cervical squamous cell carcinoma

Nuclear casein kinase and cyclin-dependent kinase substrate 1 (NUCKS1) is overexpressed in various cancer tissues and may therefore contribute to oncogenesis. However, the status of NUCKS1 expression in cervical squamous cell carcinoma (CSCC) remains unknown. Immunohistochemistry was used to determine the expression of NUCKS1 protein in 30 cervical intraepithelial neoplasias (CINs) and 125 CSCCs compared with 20 normal cervical specimens. The correlationships of NUCKS1 protein overexpression with the clinicopathologic characteristics and clinical outcomes in patients with CSCC were analysed. The status of NUCKS1 expression was negative or weak in normal tissues, but high in 21 (70.0 %) CINs and in 44 (35.2 %) CSCCs. NUCKS1 overexpression was associated with advanced International Federation of Gynaecology and Obstetrics stage (P = 0.016), poor histologic grade (P = 0.040), large tumour size (P = 0.016), parametrial involvement (P = 0.025), deep stromal infiltration (P = 0.043), lymph node metastasis (P = 0.034) and recurrence (P < 0.001). Multivariate analysis suggested that NUCKS1 overexpression was an independent factor for recurrence-free survival (RFS) (hazard ratio, 2.193; 95 % confidence interval, 1.060 to 4.535; P = 0.034). In conclusion, NUCKS1 overexpression may be associated with tumour progression and recurrence in CSCCs and may thus serve as a new molecular marker for the prediction of RFS in these patients.

Sin3a-associated Hdac1 and Hdac2 are essential for hematopoietic stem cell homeostasis and contribute differentially to hematopoiesis

Class I histone deacetylases are critical regulators of gene transcription by erasing lysine acetylation. Targeting histone deacetylases using relative non-specific small molecule inhibitors is of major interest in the treatment of cancer, neurological disorders and acquired immune deficiency syndrome. Harnessing the therapeutic potential of histone deacetylase inhibitors requires full knowledge of individual histone deacetylases in vivo. As hematologic malignancies show increased sensitivity towards histone deacetylase inhibitors we targeted deletion of class I Hdac1 and Hdac2 to hematopoietic cell lineages. Here, we show that Hdac1 and Hdac2 together control hematopoietic stem cell homeostasis, in a cell-autonomous fashion. Simultaneous loss of Hdac1 and Hdac2 resulted in loss of hematopoietic stem cells and consequently bone marrow failure. Bone-marrow-specific deletion of Sin3a, a major Hdac1/2 co-repressor, phenocopied loss of Hdac1 and Hdac2 indicating that Sin3a-associated HDAC1/2-activity is essential for hematopoietic stem cell homeostasis. Although Hdac1 and Hdac2 show compensatory and overlapping functions in hematopoiesis, mice expressing mono-allelic Hdac1 or Hdac2 revealed that Hdac1 and Hdac2 contribute differently to the development of specific hematopoietic lineages.