Over-Expression of Centromere Protein U Participates in the Malignant Neoplastic Progression of Breast Cancer

Centromere protein U mediates the ubiquitination and degradation of RPS3 to facilitate temozolomide resistance in glioblastoma

AIMS

Temozolomide (TMZ) is the first-line chemotherapeutic agent for glioblastoma (GBM) therapy; however, resistance to TMZ remains a major obstacle in GBM treatment. The aim of this study is to elucidate the mechanisms underlying TMZ resistance and explore how to enhance the sensitivity of GBM to TMZ.

METHODS

GBM organoids were generated from patient samples, and organoid-based TMZ sensitivity testing was performed. Transcriptome sequencing was conducted on GBM organoids, which identified Centromere protein U (CENPU) as a novel key gene mediating TMZ resistance. Histopathological assessments were carried out using immunohistochemistry (IHC) and Hematoxylin and Eosin (HE) staining. Single-cell sequencing data were utilized to determine the functional states of CENPU in GBM cells. Intracranial and subcutaneous glioma mouse models were constructed to evaluate the effect of CENPU on TMZ sensitivity. The underlying mechanisms were further investigated using immunofluorescence, lentivirus transduction, co-immunoprecipitation, mass spectrometry, alkaline comet assay et al. RESULTS: CENPU was found to be highly expressed in TMZ-resistant GBM organoids and enhanced the TMZ resistance of GBM cells by promoting DNA damage repair. Its abnormal expression correlates with poor clinical outcomes in glioma patients. In vivo studies demonstrated that downregulation of CENPU enhances the sensitivity of GBM to TMZ. Correspondingly, rescue of CENPU expression reversed this effect on TMZ sensitivity in GBM cells. Mechanistically, CENPU cooperates with TRIM5α to promote the ubiquitination and degradation of RPS3 by inducing its polyubiquitination at the K214 residue. This process subsequently activates the ERK1/2 pathway and promotes the expression of E2F1 and RAD51. Consequently, the degradation of RPS3 and upregulation of RAD51 in GBM cells enhance DNA damage repair, thereby contributing to TMZ resistance.

CONCLUSION

Our study identified CENPU as a novel key gene mediating TMZ resistance and elucidated its molecular mechanisms, providing a new target to overcome TMZ resistance in GBM.

DPHC from Alpinia officinarum Hance specifically modulates the function of CENPU in the cell cycle and apoptosis to ameliorate hepatocellular carcinoma

ETHNOPHARMACOLOGICAL RELEVANCE

Alpinia officinarum Hance (A. officinarum), a perennial herb used in the treatment of digestive system cancers, holds significant value for the Li people of Hainan as a traditional Chinese medicine. (R)-5-hydroxy-1,7-diphenyl-3-heptanone (DPHC), a diarylheptanoid component is derived from A. officinarum. Diarylheptanoids have demonstrated anti-proliferative effects on breast cancer cells, neuroblastoma cells, and other tumor cells. However, the pharmacological activity of DPHC in improving hepatocellular carcinoma (HCC) remains undefined.

AIM OF THE STUDY

To elucidate the anti-HCC effects of DPHC derived from A. officinarum and explore its underlying mechanistic pathways both in vivo and in vitro.

MATERIAL AND METHODS

The effects of DPHC on HCC cell lines were evaluated in vitro using cell counting kit-8, EdU cell proliferation assays, a wound healing assay, a three-dimensional tumor spheroid model, and flow cytometry. The ability of DPHC to ameliorate HCC was assessed in vivo via a nude mouse subcutaneous xenograft tumor model, serum biochemical marker detection, and hematoxylin-eosin staining. The molecular mechanism of DPHC in HCC was elucidated through a combination of transcriptome sequencing, cell transfection, immunohistochemistry assay, immunofluorescence staining, quantitative reverse transcription-PCR, and western blot analysis.

RESULTS

DPHC induced significant G0/G1 phase arrest and apoptosis in HepG2 and HCCLM3 cells while also markedly inhibiting tumor growth in nude mice. Mechanically, DPHC directly interacted with centromere-associated protein U (CENPU) to suppress its expression. The reduced expression of CENPU results in decreased interaction with the transcription factor E2F6, thereby affecting the transcriptional activity of the transcription factor E2F1. This subsequently inhibits the expression of downstream cell cycle factors (CCND1, CDK4, and CDK1) and increases apoptosis factors (Caspase 3 and Caspase 9).

CONCLUSIONS

DPHC from A. officinarum specifically modulates the function of CENPU in the cell cycle and apoptosis to ameliorate HCC. Our study revealed the anti-HCC effect and underlying mechanism of DPHC, offering new insights and potential targets for HCC treatment.

Overexpression of CENPU promotes cancer growth and metastasis and is associated with poor survival in patients with nasopharyngeal carcinoma

Background

Centromere protein U (CENPU) is key for mitosis in the carcinogenesis of cancers. However, the roles of CENPU have not been inspected in nasopharyngeal carcinoma (NPC). Thus, we aimed to explore the functions and mechanisms of CENPU in NPC.

Methods

Expression of CENPU was evaluated by real-time quantitative polymerase chain reaction, western blotting and immunohistochemistry. The biological functions of CENPU were evaluated in vitro and in vivo. Gene chip analysis, ingenuity pathway analysis, and coimmunoprecipitation experiments were used to explore the mechanisms of CENPU.

Results

CENPU was highly expressed in NPC. High expression of CENPU was associated with advanced tumor, node and metastasis (TNM) stage and poor overall survival. Cox regression analysis demonstrated that CENPU expression was an independent prognostic factor in NPC. Knockdown of CENPU inhibited proliferation and migration in vitro and in vivo. Knockdown of CENPU upregulated dual specificity phosphatase 6 (DUSP6) expression. The expression of CNEPU was inversely correlated with the expression of DUSP6 in NPC tissues. Mechanistic studies confirmed that CENPU increased the activation of the ERK1/2 and p38 signaling pathways by suppressing the expression of DUSP6.

Conclusions

CENPU acts as an oncogene in NPC by interacting with DUSP6, and may represent a promising prognostic biomarker for patients with NPC.

A pan-cancer landscape of centromere proteins in tumorigenesis and anticancer drug sensitivity

BACKGROUND

During mitosis and meiosis, centromere proteins (CENPs) play a key role in proper chromosome segregation. Abnormal expression of CENPs leads to chromosome instability, which is the main cause of tumorigenesis.

METHODS

To elucidate the functional characteristics of CENPs in pan-cancer, we comprehensively analyzed the expression landscape of CENPs and their relationships with patient survival, genomic alterations, tumor immunity, tumor microenvironment, and anticancer drug sensitivity. The expression patterns and signaling pathways of CENPs were identified through multiple bioinformatics mining and experimental verification. GEPIA2 and PrognoScan were implemented to evaluate the prognostic value of CENPs. The molecular functions of CENPs in pan-cancer were comprehensively assessed using cBioPortal, GSCA, ImmuCellAI, CellMiner, the ROC plotter tool and TIDE.

RESULTS

The results showed that CENPs were upregulated in most tumors compared with normal tissues. We confirmed this conclusion by immunohistochemistry and real-time quantitative PCR. Survival analysis revealed a significant association between high CENP expression and a poor prognosis. CENP expression is related to genome alterations, copy number variation, single nucleotide variation and methylation. Among CENP family genes, CENPF and CENPE are mutated at high frequencies in various tumors, while CENPM and CENPA are less frequently mutated. Furthermore, CENPs regulate the tumor mutational burden, stemness, and microsatellite instability, and are associated with tumor immunity. Most importantly, we revealed that CENP family gene expression was correlated with chemosensitivity and immunotherapy responses.

CONCLUSION

These findings may clarify the role of CENPs in cancer progression and antitumor drug sensitivity and provide evidence for CENPs as a potential target in pan-cancer.

A positive feedback loop of CENPU/E2F6/E2F1 facilitates proliferation and metastasis via ubiquitination of E2F6 in hepatocellular carcinoma

Centromere protein U (CENPU), a centromere-binding protein required for cellular mitosis, has been reported to be closely associated with carcinogenesis in multiple malignancies; however, the role of CENPU in hepatocellular carcinoma (HCC) is still unclear. Herein, we investigated its biological role and molecular mechanism in the development of HCC. High CENPU expression in HCC tissue was observed and correlated positively with a poor prognosis in HCC patients. CENPU knockdown inhibited the proliferation, metastasis, and G1/S transition of HCC cells in vivo and in vitro, while ectopic expression of CENPU exerted the opposite effects. Mechanistically, CENPU physically interacted with E2F6 and promoted its ubiquitin-mediated degradation, thus affecting the transcription level of E2F1 and further accelerating the G1/S transition to promote HCC cell proliferation. E2F1 directly binds to the CENPU promoter and increases the transcription of CENPU, thereby forming a positive regulatory loop. Collectively, our findings indicate a crucial role for CENPU in E2F1-mediated signalling for cell cycle progression and reveal a role for CENPU as a predictive biomarker and therapeutic target for HCC patients.

Comprehensive Analysis of the Expression and Prognostic Significance of the CENP Family in Breast Cancer

Background

Centromere proteins (CENPs) are a set of protein-coding genes involved in the transient assembly of the kinetochore which occurs during mitosis. This study intended to clarify the expression patterns, prognosis and potential mechanisms of CENPs in breast cancer (BC).

Methods

Coexpedia was used to screen GEO datasets and PubMed articles related to CENPs and BC. CENPs expressions, prognosis and alteration were analyzed by Oncomine, Ualcan and Kaplan Meier plotter and cBioPortal. The correlation and interaction of CENPs was performed by Breast Cancer Gene-Expression Miner, GeneMANIA and STRING portal. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis were conducted to clarify the functional roles of CENPs. CENPF, E, U, A, N, I, K, W, M, L were selected for further analysis.

Results

All CENPs were highly expressed in BC compared to normal tissue. High expression of CENPF, E, U, A, N, I, W, M, L and CENPF, E, U, A, N, I, M correlated with worse relapse free survival (RFS) and worse overall survival (OS), respectively. All of 10 CENPs indicated positive correlations and complex interactions between each other at mRNA expression and protein level. CENPs were enriched GO terms mainly in centromere complex assembly and KEGG terms in progesterone-mediated oocyte maturation, cell cycle and oocyte meiosis.

Conclusion

The 10 CENPs could be diagnostic biomarkers and all of them except CENPK can be used as prognosis biomarkers in BC. CENPs play an oncogenic role and may be the potential therapy targets of treatment for BC patients.

The centromere-associated protein CENPU promotes cell proliferation, migration, and invasiveness in lung adenocarcinoma

CENPU, encoding an important factor involved in kinetochore assembly during mitosis, is associated with shorter survival rates in lung adenocarcinoma (LUAD) patients. CENPU promotes growth rates and invasive behavior of LUAD cells; however, its mechanism of action in LUAD progression remains to be elucidated. CENPU mRNA and protein expression were elevated in LUAD tumors, and high CENPU gene expression was associated with inferior survival prognosis in LUAD patients. CENPU knockdown inhibited LUAD cell proliferation, clone formation, migration, invasion, and epithelial-mesenchymal transition (EMT) in addition to inducing cell cycle arrest and apoptosis in vitro and reduced LUAD xenograft tumor growth in vivo. Furthermore, we identified CENPU-regulated genes significantly enriched for proliferation and apoptosis pathways, and identified HSP Family Member C10 (DNAJC10) as putative effector of CENPU. CENPU knockdown produced DNAJC10 protein downregulation, and DNAJC10 overexpression partially rescued the phenotypic effects of CENPU knockdown in LUAD cells. Moreover, CENPU's coiled-coil domain was essential for CENPU's phenotypic effects in LUAD cells. In conclusion, the kinetochore component CENPU plays a critical role in LUAD cell proliferation and invasiveness. Targeting CENPU-DNAJC10 axis may inhibit LUAD tumor cell proliferation and metastasis.