CENP-C/H/I/K/M/T/W/N/L and hMis12 but not CENP-S/X participate in complex formation in the nucleoplasm of living human interphase cells outside centromeres

Functional enrichment analysis reveals the involvement of DARS2 in multiple biological pathways and its potential as a therapeutic target in esophageal carcinoma

OBJECTIVE

The enzyme Aspartyl tRNA synthetase 2 (DARS2) is a crucial enzyme in the mitochondrial tRNA synthesis pathway, playing a critical role in maintaining normal mitochondrial function and protein synthesis. However, the role of DARS2 in ESCA is unclear.

MATERIALS AND METHODS

Transcriptional data of pan-cancer and ESCA were downloaded from UCSC XENA, TCGA, and GEO databases to analyze the differential expression of DARS2 between tumor samples and normal samples, and its correlation with clinicopathological features of ESCA patients. R was used for GO, KEGG, and GSEA functional enrichment analysis of DARS2 co-expression and to analyze the connection of DARS2 with glycolysis and m6A-related genes. In vitro experiments were performed to assess the effects of interfering with DARS2 expression on ESCA cells. TarBase v.8, mirDIP, miRTarBase, ENCORI, and miRNet databases were used to analyze and construct a ceRNA network containing DARS2.

RESULTS

DARS2 was overexpressed in various types of tumors. In vitro experiments confirmed that interfering with DARS2 expression significantly affected the proliferation, migration, apoptosis, cell cycle, and glycolysis of ESCA cells. DARS2 may be involved in multiple biological pathways related to tumor development. Furthermore, correlation and differential analysis revealed that DARS2 may regulate ESCA m6A modification through its interaction with METTL3 and YTHDF1. A ceRNA network containing DARS2, DLEU2/has-miR-30a-5p/DARS2, was successfully predicted and constructed.

CONCLUSIONS

Our findings reveal the upregulation of DARS2 in ESCA and its association with clinical features, glycolysis pathway, m6A modification, and ceRNA network. These discoveries provide valuable insights into the molecular mechanisms underlying ESCA.

Centromeric protein K (CENPK) promotes gastric cancer proliferation and migration via interacting with XRCC5

BACKGROUND

CENPK is a novel oncogene which is aberrantly expression in some malignant tumors. However, the role and mechanisms of CENPK in gastric cancer have not been explored.

METHODS

In this study, we use RT-PCR and IHC to study CENPK expression in gastric cancer cells and tissues. In addition, we constructed the two kinds of CENPK siRNA lentivirus to knock down CENPK. Then, we use High content living cell imaging System, Cell Counting Kit-8, colony formation, wound healing and Transwell assays to demonstrate the function of CENPK on gastric cancer cells AGS and MKN45. Meanwhile, we use flow cytometry assay to study CENPK function on gastric cancer cell apoptosis and cell cycle arrest. Subcutaneous tumorigenesis in nude mice was also performed to confirm CENPK function on gastric cancer. Finally, we use Co-IP, LC-MS and function rescue assay to study the downstream interaction molecular of CENPK.

RESULTS

We demonstrated that CENPK expression were up-regulated in GC cell lines. Poor differentiation and III-IV stage had more percentages of high CENPK expression. Knocking down CENPK could significantly suppress GC cells proliferation, migration and invasion, and induce GC cells apoptosis and G1/S phase transition arrest. Subcutaneous tumorigenesis confirmed the tumor-promoting effects of CENPK in vivo. Remarkably, we found for the first time that XRCC5 might be interacted with CENPK through Co-IP, LC-MS and rescue study.

CONCLUSION

CENPK promotes GC cell proliferation and migration via interacting with XRCC5 and may be a novel prognostic factor or therapeutic target for CENPK.

Upregulation of CENPM facilitates lung adenocarcinoma progression via PI3K/AKT/mTOR signaling pathway

Centromere protein M (CENPM) is essential for chromosome separation during mitosis. However, its roles in lung adenocarcinoma (LUAD) progression and metastasis remain unknown. In this study, we aimed to explore the effects of CENPM on LUAD progression as well as the underlying mechanisms. We analyzed the expression of CENPM and its correlation with clinicopathological characteristics using GEO LUAD chip datasets and TCGA dataset. We further investigated the impact of CENPM on LUAD and . In silico analysis and qRT-PCR revealed that CENPM is upregulated in LUAD compared with that in normal lung tissues. Via gain/loss-of-function assays, we further found that CENPM promotes the LUAD cell cycle, cell proliferation, migration and invasion, and inhibits cell apoptosis. The study showed that loss of CENPM inhibits the growth of A549 xenografts. Furthermore, we found that CENPM can promote the phosphorylation of mTOR rather than directly affect the mTOR content. Inhibition of mTOR activity abrogates the promoting effects of CENPM on cell cycle progression, cell proliferation, migration and invasion. Taken together, these results show that CENPM plays an important role in the growth and metastasis of LUAD and may be a promising therapeutic target in LUAD.

CENPN Acts as a Novel Biomarker that Correlates With the Malignant Phenotypes of Glioma Cells

Background: Gliomas are the most common intracranial malignant neoplasms and have high recurrence and mortality rates. Recent literatures have reported that centromere protein N (CENPN) participates in tumor development. However, the clinicopathologic significance and biological functions of CENPN in glioma are still unclear.

Methods: Clinicopathologic data and gene expression profiles of glioma cases downloaded from The Cancer Genome Atlas (TCGA) and Chinese Glioma Genome Atlas (CGGA) databases were utilized to determine the associations between the expression of CENPN and clinical features of glioma. Kaplan-Meier and ROC curves were plotted for prognostic analysis. Gene set enrichment analysis (GSEA) and single sample gene set enrichment analysis (ssGSEA) were applied to identify immune-related functions and pathways associated with CENPN’ differential expression. In vitro experiments were conducted to investigate the impacts of CENPN on human glioma cells.

Results: Elevated CENPN expression was associated with unfavorable clinical variables of glioma patients, which was validated in clinical specimens obtained from our institution by immunohistochemical staining (IHC). The GSEA and ssGSEA results revealed that CENPN expression was strongly correlated with inflammatory activities, immune-related signaling pathways and the infiltration of immune cells. Cell experiments showed that CENPN deficiency impaired cell proliferation, migration and invasion ability and increased glioma apoptosis.

Conclusion: CENPN could be a promising therapeutic target for glioma.

A nomogram based on CENPP expression for survival prediction in breast cancer

Background

In recent years, it has been found that the expression of 17 centromere proteins (CENPs) was closely related to malignant tumors, however, the role of CENPs in breast cancer (BC) has not been fully investigated. This study intends to investigate the prognostic value of CENPs in BC and establish nomogram based on expression of CENPs to predict BC patients' prognosis.

Methods

A total of 800 BC patients with complete relevant data were included from the TCGA database and were further randomly divided into training set (N=480) and validation set (N=320). Univariate and multivariate Cox regression analysis were used to screen independent factors for overall survival (OS) prediction of BC patients in the training set. Then, the nomogram was established based on these independent predictors and further validated by receiver-operating characteristic (ROC) curves and calibration plots. The GEPIA and bcGenExMiner v4.4 databases were utilized to analyze mRNA expression of candidate gene in BC patients with different clinicopathological features, respectively.

Results

Multivariate Cox regression analysis showed that age, Her2 status, pathologic_T stage, pathologic_M stage and CENPP expression were of independent prognostic value for BC. CENPP was overexpressed in BC tissues (P<0.01) and lower expression of CENPP was associated with worse OS (P=0.005, HR =2.35; 95% CI: 1.30-4.23). We then established a nomogram based on those independent predictors, and the calibration curve demonstrated good fitness of the nomogram for OS prediction. In the training set, the AUCs of 3- and 5-year survival were 0.757 and 0.797, respectively. In the validation set, the AUCs of 3- and 5-year survival were 0.727 and 0.71, respectively.

Conclusions

Our study showed that CENPP was a novel prognostic factor for patients with BC, and the established nomogram could provide valuable information on prognostic prediction for patients with BC.

The PVT1/miR-612/CENP-H/CDK1 axis promotes malignant progression of advanced endometrial cancer

Our previous study introduced the oncogenic role of the long non-coding RNA plasmacytoma variant translocation 1 (PVT1) in endometrial cancer (EC). In this study, we aimed to construct a PVT1-centered competing endogenous RNA (ceRNA) network to outline a regulatory axis that might promote the malignant progression of advanced EC. Raw Uterine Corpus Endometrial Carcinoma (UCEC) datasets were collected from The Cancer Genome Atlas (TCGA) database and used for construction of the PVT1-centered ceRNA network. The ceRNA binding sites were established using dual-luciferase assays. FISH assays displayed the co-location of PVT1 and miR-612 in EC cells. Immunohistochemistry, in situ hybridization, qRT-PCR, and western blots were used to assess the expression of miR-612 and CENP-H in EC tissues, and their functions on biological behaviours were examined by a series of in vitro and in vivo assays. Molecule interactions were illustrated by co-transfection assays. The bioinformatics analysis showed that PVT1/miR-612/CENP-H/CDK1 axis played a vital role in the malignant progression of advanced EC. MiR-612 was downregulated in EC tissues and acted as a tumour suppressor to inhibit cell proliferation, migration, invasion, and promote cell apoptosis. CENP-H was found overexpressed in EC tissues, and the expression level was correlated to diagnosis and prognosis of EC. Hyperactivated CENP-H promoted cell proliferation, migration, invasion, and inhibited cell apoptosis. Overexpressed CENP-H prevented the anti-tumour effects observed with upregulated miR-612; knockdown of miR-612 also suppressed the anti-tumour effects of downregulated PVT1. Knockdown of PVT1 together with upregulated miR-612 exerted the strongest anti-tumour effects in nude mice. These effects were mediated by CDK1 through modulation of the Akt/mTOR signaling pathway. In conclusion, the PVT1/miR-612/CENP-H/CDK1 axis promoted the malignant progression of advanced EC and could serve as a promising target for potential treatments.

Heat Shock Cognate 70 Functions as A Chaperone for the Stability of Kinetochore Protein CENP-N in Holocentric Insect Silkworms

The centromere, in which kinetochore proteins are assembled, plays an important role in the accurate congression and segregation of chromosomes during cell mitosis. Although the function of the centromere and kinetochore is conserved from monocentric to holocentric, the DNA sequences of the centromere and components of the kinetochore are varied among different species. Given the lack of core centromere protein A (CENP-A) and CENP-C in the lepidopteran silkworm Bombyx mori, which possesses holocentric chromosomes, here we investigated the role of CENP-N, another important member of the centromere protein family essential for kinetochore assembly. For the first time, cellular localization and RNA interference against CENP-N have confirmed its kinetochore function in silkworms. To gain further insights into the regulation of CENP-N in the centromere, we analyzed the affinity-purified complex of CENP-N by mass spectrometry and identified 142 interacting proteins. Among these factors, we found that the chaperone protein heat shock cognate 70 (HSC70) is able to regulate the stability of CENP-N by prohibiting ubiquitin-proteasome pathway, indicating that HSC70 could control cell cycle-regulated degradation of CENP-N at centromeres. Altogether, the present work will provide a novel clue to understand the regulatory mechanism for the kinetochore activity of CENP-N during the cell cycle.

A three-gene novel predictor for improving the prognosis of cervical cancer

Cervical cancer is the most common gynecological malignancy, the third most common malignant tumor in women worldwide, and the most common malignant tumor among Chinese women. However, despite continuous improvement in medical treatment, the number of cervical cancer cases in China is on the increase annually, consistent with the general trend in global cervical cancer incidence. Therefore, it is particularly important to study the pathogenesis of cervical cancer at the genetic level in China. The aim of the present study was to use the TCGA database to identify potential genetic signatures that could predict the prognosis of patients with cervical cancer and provide evidence supporting clinical genetic intervention in cervical cancer. Primarily, an effective three-gene signature was found that predicts prognosis in patients with cervical cancer. This model can provide prima facie evidence for future assessment of patient risk and prognosis, but further testing is required to improve its accuracy. Our results also suggested that centromere protein M, methionine sulfoxide reductase B3 and Zic family member 2 could be promising biomarkers for the prognosis of cervical cancer.

Centromere Protein N Participates in Cellular Proliferation of Human Oral Cancer by Cell-Cycle Enhancement

Centromere protein N (CENP-N), an important member of the centromere protein family, is essential for kinetochore assembly and chromosome segregation; however, the relevance of CENP-N in cancers remains unknown. The aim of this study was to investigate CENP-N expression and its functional mechanisms in oral squamous cell carcinoma (OSCC). CENP-N expression was up-regulated significantly in vitro and in vivo in OSCCs. Overexpressed CENP-N was closely (p < 0.05) correlated with tumor growth using quantitative reverse transcriptase-polymerase chain reaction, immunoblot analysis, and immunohistochemistry. CENP-N knockdown (shCENP-N) cells showed depressed cellular proliferation by cell-cycle arrest at the G1 phase with up-regulation of p21^Cip1 and p27^Kip1 and down-regulation of cyclin D1, CDK2, and CDK4. Interestingly, we newly discovered that calcitriol (1, 25-dihydroxyvitamin D3) controlled the CENP-N expression level, leading to inhibition of tumor growth similar to shCENP-N cells. These results suggested that CENP-N plays a critical role in determining proliferation of OSCCs and that calcitriol might be a novel therapeutic drug for OSCCs by regulating CENP-N.