DNAJC9 prevents CENP-A mislocalization and chromosomal instability by maintaining the fidelity of histone supply chains.

The centromeric histone H3 variant CENP-A is overexpressed in many cancers. The mislocalization of CENP-A to noncentromeric regions contributes to chromosomal instability (CIN), a hallmark of cancer. However, pathways that promote or prevent CENP-A mislocalization remain poorly defined. Here, we performed a genome-wide RNAi screen for regulators of CENP-A localization which identified DNAJC9, a J-domain protein implicated in histone H3-H4 protein folding, as a factor restricting CENP-A mislocalization. Cells lacking DNAJC9 exhibit mislocalization of CENP-A throughout the genome, and CIN phenotypes. Global interactome analysis showed that DNAJC9 depletion promotes the interaction of CENP-A with the DNA-replication-associated histone chaperone MCM2. CENP-A mislocalization upon DNAJC9 depletion was dependent on MCM2, defining MCM2 as a driver of CENP-A deposition at ectopic sites when H3-H4 supply chains are disrupted. Cells depleted for histone H3.3, also exhibit CENP-A mislocalization. In summary, we have defined novel factors that prevent mislocalization of CENP-A, and demonstrated that the integrity of H3-H4 supply chains regulated by histone chaperones such as DNAJC9 restrict CENP-A mislocalization and CIN.

Cdc48 and its co-factor Ufd1 extract CENP-A from centromeric chromatin and can induce chromosome elimination in the fission yeast Schizosaccharomyces pombe.

CENP-A determines the identity of the centromere. Because the position and size of the centromere and its number per chromosome must be maintained, the distribution of CENP-A is strictly regulated. In this study, we have aimed to understand mechanisms to regulate the distribution of CENP-A (Cnp1SP) in fission yeast. A mutant of the ufd1+ gene (ufd1-73) encoding a cofactor of Cdc48 ATPase is sensitive to Cnp1 expressed at a high level and allows mislocalization of Cnp1. The level of Cnp1 in centromeric chromatin is increased in the ufd1-73 mutant even when Cnp1 is expressed at a normal level. A preexisting mutant of the cdc48+ gene (cdc48-353) phenocopies the ufd1-73 mutant. We have also shown that Cdc48 and Ufd1 proteins interact physically with centromeric chromatin. Finally, Cdc48 ATPase with Ufd1 artificially recruited to the centromere of a mini-chromosome (Ch16) induce a loss of Cnp1 from Ch16, leading to an increased rate of chromosome loss. It appears that Cdc48 ATPase, together with its cofactor Ufd1 remove excess Cnp1 from chromatin, likely in a direct manner. This mechanism may play a role in centromere disassembly, a process to eliminate Cnp1 to inactivate the kinetochore function during development, differentiation, and stress response.

CENPA promotes glutamine metabolism and tumor progression by up-regulating SLC38A1 in endometrial cancer.

Glutamine addiction is a significant hallmark of metabolic reprogramming in tumors and is crucial to the progression of cancer. Nevertheless, the regulatory mechanisms of glutamine metabolism in endometrial cancer (EC) remains elusive. In this research, we found that elevated expression of CENPA and solute carrier family 38 member 1 (SLC38A1) were firmly associated with worse clinical stage and unfavorable outcomes in EC patients. In addition, ectopic overexpression or silencing of CENPA could either enhance or diminish glutamine metabolism and tumor progression in EC. Mechanistically, CENPA directly regulated the transcriptional activity of the target gene, SLC38A1, leading to enhanced glutamine uptake and metabolism, thereby promoting EC progression. Notably, a prognostic model utilizing the expression levels of CENPA and SLC38A1 genes independently emerged as a prognostic factor for EC. More importantly, CENPA and SLC38A1 were significantly elevated and positively correlated, as well as indicative of poor prognosis in multiple cancers. In brief, our study confirmed that CENPA is a critical transcription factor involved in glutamine metabolism and tumor progression through modulating SLC38A1. This revelation suggests that targeting CENPA could be an appealing therapeutic approach to address pan-cancer glutamine addiction.

CENPA knockdown restrains cell progression and tumor growth in breast cancer by reducing PLA2R1 promoter methylation and modulating PLA2R1/HHEX axis.

BACKGROUND: Breast cancer is a lethal malignancy affecting females worldwide. It has been reported that upregulated centromere protein A (CENPA) expression might indicate unfortunate prognosis and can function as a prognostic biomarker in breast cancer. This study aimed to investigate the accurate roles and downstream mechanisms of CENPA in breast cancer progression. METHODS: CENPA protein levels in breast cancer tissues and cell lines were analyzed by Western blot and immunohistochemistry assays. We used gain/loss-of-function experiments to determine the potential effects of CENPA and phospholipase A2 receptor (PLA2R1) on breast cancer cell proliferation, migration, and apoptosis. Co-IP assay was employed to validate the possible interaction between CENPA and DNA methyltransferase 1 (DNMT1), as well as PLA2R1 and hematopoietically expressed homeobox (HHEX). PLA2R1 promoter methylation was determined using methylation-specific PCR assay. The biological capabilities of CENPA/PLA2R1/HHEX axis in breast cancer cells was determined by rescue experiments. In addition, CENPA-silenced MCF-7 cells were injected into mice, followed by measurement of tumor growth. RESULTS: CENPA level was prominently elevated in breast cancer tissues and cell lines. Interestingly, CENPA knockdown and PLA2R1 overexpression both restrained breast cancer cell proliferation and migration, and enhanced apoptosis. On the contrary, CENPA overexpression displayed the opposite results. Moreover, CENPA reduced PLA2R1 expression through promoting DNMT1-mediated PLA2R1 promoter methylation. PLA2R1 overexpression could effectively abrogate CENPA overexpression-mediated augment of breast cancer cell progression. Furthermore, PLA2R1 interacted with HHEX and promoted HHEX expression. PLA2R1 knockdown increased the rate of breast cancer cell proliferation and migration but restrained apoptosis, which was abrogated by HHEX overexpression. In addition, CENPA silencing suppressed tumor growth in vivo. CONCLUSION: CENPA knockdown restrained breast cancer cell proliferation and migration and attenuated tumor growth in vivo through reducing PLA2R1 promoter methylation and increasing PLA2R1 and HHEX expression. We may provide a promising prognostic biomarker and novel therapeutic target for breast cancer.

HJURP is recruited to double-strand break sites and facilitates DNA repair by promoting chromatin reorganization.

HJURP is overexpressed in several cancer types and strongly correlates with patient survival. However, the mechanistic basis underlying the association of HJURP with cancer aggressiveness is not well understood. HJURP promotes the loading of the histone H3 variant, CENP-A, at the centromeric chromatin, epigenetically defining the centromeres and supporting proper chromosome segregation. In addition, HJURP is associated with DNA repair but its function in this process is still scarcely explored. Here, we demonstrate that HJURP is recruited to DSBs through a mechanism requiring chromatin PARylation and promotes epigenetic alterations that favor the execution of DNA repair. Incorporation of HJURP at DSBs promotes turnover of H3K9me3 and HP1, facilitating DNA damage signaling and DSB repair. Moreover, HJURP overexpression in glioma cell lines also affected global structure of heterochromatin independently of DNA damage induction, promoting genome-wide reorganization and assisting DNA damage response. HJURP overexpression therefore extensively alters DNA damage signaling and DSB repair, and also increases radioresistance of glioma cells. Importantly, HJURP expression levels in tumors are also associated with poor response of patients to radiation. Thus, our results enlarge the understanding of HJURP involvement in DNA repair and highlight it as a promising target for the development of adjuvant therapies that sensitize tumor cells to irradiation.

The cysteine-rich domain in CENP-A chaperone Scm3HJURP ensures centromere targeting and kinetochore integrity.

Centromeric chromatin plays a crucial role in kinetochore assembly and chromosome segregation. Centromeres are specified through the loading of the histone H3 variant CENP-A by the conserved chaperone Scm3/HJURP. The N-terminus of Scm3/HJURP interacts with CENP-A, while the C-terminus facilitates centromere localization by interacting with the Mis18 holocomplex via a small domain, called the Mis16-binding domain (Mis16-BD) in fission yeast. Fungal Scm3 proteins contain an additional conserved cysteine-rich domain (CYS) of unknown function. Here, we find that CYS binds zinc in vitro and is essential for the localization and function of fission yeast Scm3. Disrupting CYS by deletion or introduction of point mutations within its zinc-binding motif prevents Scm3 centromere localization and compromises kinetochore integrity. Interestingly, CYS alone can localize to the centromere, albeit weakly, but its targeting is greatly enhanced when combined with Mis16-BD. Expressing a truncated protein containing both Mis16-BD and CYS, but lacking the CENP-A binding domain, causes toxicity and is accompanied by considerable chromosome missegregation and kinetochore loss. These effects can be mitigated by mutating the CYS zinc-binding motif. Collectively, our findings establish the essential role of the cysteine-rich domain in fungal Scm3 proteins and provide valuable insights into the mechanism of Scm3 centromere targeting.

Interaction of histone H4 with Cse4 facilitates conformational changes in Cse4 for its sumoylation and mislocalization.

Mislocalization of overexpressed CENP-A (Cse4 in budding yeast, Cnp1 in fission yeast, CID in flies) contributes to chromosomal instability (CIN) in yeasts, flies, and human cells. Mislocalization of CENP-A is observed in many cancers and this correlates with poor prognosis. Structural mechanisms that contribute to mislocalization of CENP-A are poorly defined. Here, we show that interaction of histone H4 with Cse4 facilitates an in vivo conformational change in Cse4 promoting its mislocalization in budding yeast. We determined that Cse4 Y193A mutant exhibits reduced sumoylation, mislocalization, interaction with histone H4, and lethality in psh1Δ and cdc48-3 strains; all these phenotypes are suppressed by increased gene dosage of histone H4. We developed a new in vivo approach, antibody accessibility (AA) assay, to examine the conformation of Cse4. AA assay showed that wild-type Cse4 with histone H4 is in an 'open' state, while Cse4 Y193A predominantly exhibits a 'closed' state. Increased gene dosage of histone H4 contributes to a shift of Cse4 Y193A to an 'open' state with enhanced sumoylation and mislocalization. We provide molecular insights into how Cse4-H4 interaction changes the conformational state of Cse4 in vivo. These studies advance our understanding for mechanisms that promote mislocalization of CENP-A in human cancers.

CENPA functions as a transcriptional regulator to promote hepatocellular carcinoma progression via cooperating with YY1.

The centromere proteins (CENPs), a critical mitosis-related protein complexes, are involved in the kinetochore assembly and chromosome segregation. In this study, we identified that CENPA was significantly up-regulated in HCC and highly expressed CENPA correlated with poor prognosis for HCC patients. Knockdown of CENPA inhibited HCC cell proliferation and tumor growth in vitro and in vivo. Mechanistically, CENPA transcriptionally activated and cooperated with YY1 to drive the expression of cyclin D1 (CCND1) and neuropilin 2 (NRP2). Moreover, we identified that CENPA can be lactylated at lysine 124 (K124). The lactylation of CENPA at K124 promotes CENPA activation, leading to enhanced expression of its target genes. In summary, CENPA function as a transcriptional regulator to promote HCC via cooperating with YY1. Targeting the CENPA-YY1-CCND1/NRP2 axis may provide candidate therapeutic targets for HCC.

Misregulation of cell cycle-dependent methylation of budding yeast CENP-A contributes to chromosomal instability.

Centromere (CEN) identity is specified epigenetically by specialized nucleosomes containing evolutionarily conserved CEN-specific histone H3 variant CENP-A (Cse4 in Saccharomyces cerevisiae, CENP-A in humans), which is essential for faithful chromosome segregation. However, the epigenetic mechanisms that regulate Cse4 function have not been fully defined. In this study, we show that cell cycle-dependent methylation of Cse4-R37 regulates kinetochore function and high-fidelity chromosome segregation. We generated a custom antibody that specifically recognizes methylated Cse4-R37 and showed that methylation of Cse4 is cell cycle regulated with maximum levels of methylated Cse4-R37 and its enrichment at the CEN chromatin occur in the mitotic cells. Methyl-mimic cse4-R37F mutant exhibits synthetic lethality with kinetochore mutants, reduced levels of CEN-associated kinetochore proteins and chromosome instability (CIN), suggesting that mimicking the methylation of Cse4-R37 throughout the cell cycle is detrimental to faithful chromosome segregation. Our results showed that SPOUT methyltransferase Upa1 contributes to methylation of Cse4-R37 and overexpression of UPA1 leads to CIN phenotype. In summary, our studies have defined a role for cell cycle-regulated methylation of Cse4 in high-fidelity chromosome segregation and highlight an important role of epigenetic modifications such as methylation of kinetochore proteins in preventing CIN, an important hallmark of human cancers.

High expression of centromere protein A and its molecular mechanism and clinical significance in prostate cancer: A study based on data mining and immunohistochemistry.

The progression of prostate cancer (PCa) leads to poor prognosis. However, the molecular mechanism of PCa is still not completely clear. This study aimed to elucidate the important role of centromere protein A (CENPA) in PCa. Large numbers of bulk RNA sequencing (RNA-seq) data and in-house immunohistochemistry data were used in analysing the expression level of CENPA in PCa and metastatic PCa (MPCa). Single-cell RNA-seq data was used to explore the expression status of CENPA in different prostate subpopulations. Enrichment analysis was employed to detect the function of CENPA in PCa. Clinicopathological parameters analysis was utilised in analysing the clinical value of CENPA. The results showed that CENPA was upregulated in PCa (standardised mean difference [SMD] = 0.83, p = 0.001) and MPCa (SMD = 0.61, p = 0.029). CENPA was overexpressed in prostate cancer stem cells (CSCs) with androgen receptor (AR) negative compared to epithelial cells with AR positive. CENPA may influence the development of PCa through affecting cell cycle. Patients with nodal metastasis had higher expression level of CENPA. And patients with high CENPA expression had poor disease-free survival. Taken together, Overexpression of CENPA may influence the development of PCa by regulating cell cycle and promoting metastasis.

EWSR1 maintains centromere identity.

The centromere is essential for ensuring high-fidelity transmission of chromosomes. CENP-A, the centromeric histone H3 variant, is thought to be the epigenetic mark of centromere identity. CENP-A deposition at the centromere is crucial for proper centromere function and inheritance. Despite its importance, the precise mechanism responsible for maintenance of centromere position remains obscure. Here, we report a mechanism to maintain centromere identity. We demonstrate that CENP-A interacts with EWSR1 (Ewing sarcoma breakpoint region 1) and EWSR1-FLI1 (the oncogenic fusion protein in Ewing sarcoma). EWSR1 is required for maintaining CENP-A at the centromere in interphase cells. EWSR1 and EWSR1-FLI1 bind CENP-A through the SYGQ2 region within the prion-like domain, important for phase separation. EWSR1 binds to R-loops through its RNA-recognition motif in vitro. Both the domain and motif are required for maintaining CENP-A at the centromere. Therefore, we conclude that EWSR1 guards CENP-A in centromeric chromatins by binding to centromeric RNA.

ATR protects centromere identity by promoting DAXX association with PML nuclear bodies.

Centromere protein A (CENP-A) defines centromere identity and nucleates kinetochore formation for mitotic chromosome segregation. Here, we show that ataxia telangiectasia and Rad3-related (ATR) kinase, a master regulator of the DNA damage response, protects CENP-A occupancy at interphase centromeres in a DNA damage-independent manner. In unperturbed cells, ATR localizes to promyelocytic leukemia nuclear bodies (PML NBs), which house the histone H3.3 chaperone DAXX (death domain-associated protein 6). We find that ATR inhibition reduces DAXX association with PML NBs, resulting in the DAXX-dependent loss of CENP-A and an aberrant increase in H3.3 at interphase centromeres. Additionally, we show that ATR-dependent phosphorylation within the C terminus of DAXX regulates CENP-A occupancy at centromeres and DAXX localization. Lastly, we demonstrate that acute ATR inhibition during interphase leads to kinetochore formation defects and an increased rate of lagging chromosomes. These findings highlight a mechanism by which ATR protects centromere identity and genome stability.

The histone H3/H4 chaperone CHAF1B prevents the mislocalization of CENP-A for chromosomal stability.

Restricting the localization of the evolutionarily conserved centromeric histone H3 variant CENP-A to centromeres prevents chromosomal instability (CIN). The mislocalization of CENP-A to non-centromeric regions contributes to CIN in yeasts, flies and human cells. Even though overexpression and mislocalization of CENP-A have been reported in cancers, the mechanisms responsible for its mislocalization remain poorly understood. Here, we used an imaging-based high-throughput RNAi screen to identify factors that prevent mislocalization of overexpressed YFP-tagged CENP-A (YFP-CENP-A) in HeLa cells. Among the top five candidates in the screen - the depletion of which showed increased nuclear YFP-CENP-A fluorescence - were the histone chaperones CHAF1B (or p60) and CHAF1A (or p150). Follow-up validation and characterization experiments showed that CHAF1B-depleted cells exhibited CENP-A mislocalization, CIN phenotypes and increased enrichment of CENP-A in chromatin fractions. The depletion of DAXX, a histone H3.3 chaperone, suppressed CENP-A mislocalization and CIN in CHAF1B-depleted cells. We propose that in CHAF1B-depleted cells, DAXX promotes mislocalization of the overexpressed CENP-A to non-centromeric regions, resulting in CIN. In summary, we identified regulators of CENP-A localization and defined a role for CHAF1B in preventing DAXX-dependent CENP-A mislocalization and CIN.

Targeted assembly of ectopic kinetochores to induce chromosome-specific segmental aneuploidies.

Cancer cells display persistent underlying chromosomal instability, with individual tumour types intriguingly exhibiting characteristic subsets of whole, and subchromosomal aneuploidies. Few methods to induce specific aneuploidies will exist, hampering investigation of functional consequences of recurrent aneuploidies, as well as the acute consequences of specific chromosome mis-segregation. We therefore investigated the possibility of sabotaging the mitotic segregation of specific chromosomes using nuclease-dead CRISPR-Cas9 (dCas9) as a cargo carrier to specific genomic loci. We recruited the kinetochore-nucleating domain of centromere protein CENP-T to assemble ectopic kinetochores either near the centromere of chromosome 9, or the telomere of chromosome 1. Ectopic kinetochore assembly led to increased chromosome instability and partial aneuploidy of the target chromosomes, providing the potential to induce specific chromosome mis-segregation events in a range of cell types. We also provide an analysis of putative endogenous repeats that could support ectopic kinetochore formation. Overall, our findings provide new insights into ectopic kinetochore biology and represent an important step towards investigating the role of specific aneuploidy and chromosome mis-segregation events in diseases associated with aneuploidy.

The ins and outs of CENP-A: Chromatin dynamics of the centromere-specific histone.

Centromeres are highly specialised chromosome domains defined by the presence of an epigenetic mark, the specific histone H3 variant called CENP-A (centromere protein A). They constitute the genomic regions on which kinetochores form and when defective cause segregation defects that can lead to aneuploidy and cancer. Here, we discuss how CENP-A is established and maintained to propagate centromere identity while subjected to dynamic chromatin remodelling during essential cellular processes like DNA repair, replication, and transcription. We highlight parallels and identify conserved mechanisms between different model organism with a particular focus on 1) the establishment of CENP-A at centromeres, 2) CENP-A maintenance during transcription and replication, and 3) the mechanisms that help preventing CENP-A localization at non-centromeric sites. We then give examples of how timely loading of new CENP-A to the centromere, maintenance of old CENP-A during S-phase and transcription, and removal of CENP-A at non-centromeric sites are coordinated and controlled by an intricate network of factors whose identity is slowly being unravelled.

CENP-A: A Histone H3 Variant with Key Roles in Centromere Architecture in Healthy and Diseased States.

Centromeres are key architectural components of chromosomes. Here, we examine their construction, maintenance, and functionality. Focusing on the mammalian centromere- specific histone H3 variant, CENP-A, we highlight its coevolution with both centromeric DNA and its chaperone, HJURP. We then consider CENP-A de novo deposition and the importance of centromeric DNA recently uncovered with the added value from new ultra-long-read sequencing. We next review how to ensure the maintenance of CENP-A at the centromere throughout the cell cycle. Finally, we discuss the impact of disrupting CENP-A regulation on cancer and cell fate.

GRANT Motif Regulates CENP-A Incorporation and Restricts RNA Polymerase II Accessibility at Centromere.

Precise chromosome segregation is essential for maintaining genomic stability, and its proper execution centers on the centromere, a chromosomal locus that mounts the kinetochore complex to mediate attachment of chromosomes to the spindle microtubules. The location of the centromere is epigenetically determined by a centromere-specific histone H3 variant, CENP-A. Many human cancers exhibit overexpression of CENP-A, which correlates with occurrence of aneuploidy in these malignancies. Centromeric targeting of CENP-A depends on its histone fold, but recent studies showed that the N-terminal tail domain (NTD) also plays essential roles. Here, we investigated implications of NTD in conferring aneuploidy formation when CENP-A is overexpressed in fission yeast. A series of mutant genes progressively lacking one amino acid of the NTD have been constructed for overexpression in wild-type cells using the intermediate strength nmt41 promoter. Constructs hosting disrupted GRANT (Genomic stability-Regulating site within CENP-A N-Terminus) motif in NTD results in growth retardation, aneuploidy, increased localization to the centromere, upregulated RNA polymerase II accessibility and transcriptional derepression of the repressive centromeric chromatin, suggesting that GRANT residues fine-tune centromeric CENP-A incorporation and restrict RNA polymerase II accessibility. This work highlighted the importance of CENP-A NTD, particularly the GRANT motif, in aneuploidy formation of overexpressed CENP-A in fission yeast.

E2F1 transcription factor mediates a link between fat and islets to promote ß cell proliferation in response to acute insulin resistance.

Prevention or amelioration of declining ß cell mass is a potential strategy to cure diabetes. Here, we report the pathways utilized by ß cells to robustly replicate in response to acute insulin resistance induced by S961, a pharmacological insulin receptor antagonist. Interestingly, pathways that include CENP-A and the transcription factor E2F1 that are independent of insulin signaling and its substrates appeared to mediate S961-induced ß cell multiplication. Consistently, pharmacological inhibition of E2F1 blocks ß-cell proliferation in S961-injected mice. Serum from S961-treated mice recapitulates replication of ß cells in mouse and human islets in an E2F1-dependent manner. Co-culture of islets with adipocytes isolated from S961-treated mice enables ß cells to duplicate, while E2F1 inhibition limits their growth even in the presence of adipocytes. These data suggest insulin resistance-induced proliferative signals from adipocytes activate E2F1, a potential therapeutic target, to promote ß cell compensation.

Unraveling the Role of Histone Variant CENP-A and Chaperone HJURP Expression in Thymic Epithelial Neoplasms.

Background: Recent advances demonstrate the role of chromatin regulators, including histone variants and histone chaperones, in cancer initiation and progression. Methods: Histone H3K4me3, histone variant centromere protein (CENP-A) and histone chaperones Holliday junction recognition protein (HJURP) as well as DAXX expression were examined immunohistochemically in 95 thymic epithelial tumor (TET) specimens. Our results were compared with the expression profile of DAXX, HJURP and CENP-A in gene expression profiling interactive analysis (GEPIA2). Results: The lymphocyte-poor B3- and C-type TETs were more frequently DAXX negative (p = 0.043). B3 and C-Type TETs showed higher cytoplasmic and nuclear CENP-A (p = 0.007 and p = 0.002) and higher cytoplasmic HJURP H-score (p < 0.001). Higher nuclear CENP-A and cytoplasmic HJURP expression was associated with advanced Masaoka−Koga stage (p = 0.048 and p < 0.001). A positive correlation between HJURP and CENP-A was also observed. The presence of cytoplasmic CENP-A expression was correlated with a favorable overall survival (p = 0.03). CENP-A overexpression in survival analysis of TCGA TETs showed similar results. H3K4me3 expression was not associated with any clinicopathological parameters. Conclusions: Our results suggest a significant interaction between CENP-A and HJURP in TETs. Moreover, we confirmed the presence of a cytoplasmic CENP-A immunolocalization, suggesting also a possible favorable prognostic value of this specific immunostaining pattern.

HJURP inhibits proliferation of ovarian cancer cells by regulating CENP-A/CENP-N.

OBJECTIVE: High expression of Holliday Junction-Recognizing Protein (HJURP) has been shown to be a marker of poor prognosis in ovarian cancer. The objective of this study was to investigate the molecular mechanisms of HJURP in ovarian cancer (OC) progression. PROCEDURES: Gene Expression Profiling Interactive Analysis (GEPIA) was used to analyze the gene expression profile. Real-time quantitative PCR (qRT-PCR) was used to detect the expression level and correlation of HJURP and centromere protein-A (CENP-A) in OC tissues and cell lines. CCK-8 assay was used to detect cell proliferation. The expression level of apoptosis-related proteins and cell cycle-related proteins were detected by western blotting. Cell cycle and mitochondrial content were determined by flow cytometry. RESULTS: The results showed that HJURP was up-regulated in OC tissues and cell lines, while the cell proliferation was inhibited after transfecting by si-HJURP. Knockdown of HJURP promoted cell apoptosis. Meanwhile, low-expression of HJURP could down-regulate cell replication cycle-related proteins (Cyclin-dependent kinase 2, cyclinD1 and Cyclin-dependent kinase 4) and make cell replication stay in the S phase. Moreover, further studies showed that HJURP was positively correlated with CENP-A in OC tissues. Finally, the rescue experiment further verified that HJURP targeted regulation of CENP-A in OC. CONCLUSIONS: The study indicated that HJURP plays a significant role in OC and could target CENP-A to regulate OC cell growth. These findings provide a clue to the diagnosis and treatment of OC.