Cell Division Cycle Associated 5 Research Articles

Therapeutic potential of targeting cell division cycle associated 5 for oral squamous cell carcinoma.

Molecularly targeted drugs are used in the treatment of a variety of malignant tumors, but this approach to developing novel therapies for oral squamous cell carcinoma (OSCC) has lagged behind the progress seen for other cancers. We have attempted to find appropriate molecular targets for OSCC and identified cell division cycle associated 5 (CDCA5) as a cancer-related gene which was overexpressed in all the human OSCC cells tested by microarray analysis. In this study, we investigated the expression and function of CDCA5 in OSCC. First, we confirmed that CDCA5 was overexpressed in 4 human OSCC cell lines by quantitative RT-PCR and Western blotting. We then tested the effect of synthetic small interfering RNAs specific for CDCA5 on the growth and invasion of human OSCC cells. Knockdown of CDCA5 markedly inhibited the growth of OSCC cells in vitro and in vivo. We also examined the expression of CDCA5 protein in 80 cases of OSCC immunohistochemically and found a significant association between CDCA5 expression levels and overall survival. These results suggest that CDCA5 functions as a critical gene supporting OSCC progression and that targeting CDCA5 may be a useful therapeutic strategy for OSCC.

Transcriptional Activation of Human CDCA8 Gene Regulated by Transcription Factor NF-Y in Embryonic Stem Cells and Cancer Cells

The cell division cycle associated 8 (CDCA8) gene plays an important role in mitosis. Overexpression of CDCA8 was reported in some human cancers and is required for cancer growth and progression. We found CDCA8 expression was also high in human ES cells (hESCs) but dropped significantly upon hESC differentiation. However, the regulation of CDCA8 expression has not yet been studied. Here, we characterized the CDCA8 promoter and identified its cis-elements and transcription factors. Three transcription start sites were identified. Reporter gene assays revealed that the CDCA8 promoter was activated in hESCs and cancer cell lines. The promoter drove the reporter expression specifically to pluripotent cells during early mouse embryo development and to tumor tissues in tumor-bearing mice. These results indicate that CDCA8 is transcriptionally activated in hESCs and cancer cells. Mechanistically, two key activation elements, bound by transcription factor NF-Y and CREB1, respectively, were identified in the CDCA8 basic promoter by mutation analyses and electrophoretic motility shift assays. NF-Y binding is positively correlated with promoter activities in different cell types. Interestingly, the NF-YA subunit, binding to the promoter, is primarily a short isoform in hESCs and a long isoform in cancer cells, indicating a different activation mechanism of the CDCA8 transcription between hESCs and cancer cells. Finally, enhanced CDCA8 promoter activities by NF-Y overexpression and reduced CDCA8 transcription by NF-Y knockdown further verified that NF-Y is a positive regulator of CDCA8 transcription. Our study unearths the molecular mechanisms underlying the activation of CDCA8 expression in hESCs and cancer cells, which provides a better understanding of its biological functions.

Expression of CDCA8 correlates closely with FOXM1 in breast cancer: public microarray data analysis and immunohistochemical study.

Forkhead Box M1 (FOXM1) is an oncogenic transcription factor implicated in breast cancer progression and metastasis. However, the clinical significance of FOXM1 and its associated signaling genes in human breast cancer still needed to be clarified. In this study, we first analyzed the co-expression gene pattern of FOXM1 in three breast cancer gene expression microarray datasets from the Oncomine database. Cell division cycle associated 8 (CDCA8) gene was identified to correlate closely with FOXM1. In silico analysis further indicated that CDCA8 overexpressed in breast cancer tissues compared with the normal controls is significantly associated with the triple-negative phenotype. Experimentally, we performed aimmunohistochemical study to detect the expression of CDCA8 in 112 breast cancer samples, and evaluated its clinicopathological and prognostic significance. We found that CDCA8 was frequently over-expressed in breast cancer tissues, and increased expression of CDCA8 was positively associated with FOXM1 expression, triple-negative phenotype and shorter overall survival. Moreover, we also found that combination of CDCA8 and FOXM1 showed ahigher hazard ratio than the individual markers. Our results suggest that FOXM1-CDCA8 signature might be involved in breast cancer progression, and serves as apotential prognostic factor and apromising therapeutical target.

Abstract 476: Overexpression and function of CDCA5 in oral squamous cell carcinoma

Abstract Molecular target drugs are used in the treatment of various malignant tumors. However, the development of molecular targeted therapy for oral squamous cell carcinoma (OSCC) is lagging behind other cancers. In this study, we have attempted to identify an appropriate molecular target for treatment of patients with OSCC. We determined the gene expression profiles of human 9 OSCC cell lines and an immortalized non-neoplastic human keratinocyte cell line by microarray analysis, and then found cell division cycle associated 5 (CDCA5) as one of genes which were commonly overexpressed in OSCC cells. CDCA5 was initially identified as substrate of anaphase-promoting complex and as a regulator of sister chromatid cohesion in HeLa. In addition, it has been reported that CDCA5 plays a critical role in human lung carcinogenesis. However, function of CDCA5 in OSCC remains still unknown. First, we confirmed the overexpression of CDCA5 in 5 human OSCC cells by quantitative RT-PCR (qRT-PCR) and Western blotting. The expression levels of CDCA5 mRNA and protein were markedly elevated in all human OSCC cell lines compared to a non-neoplastic human epithelial cell line. Next, we examined the effect of synthetic small interfering RNAs specific for CDCA5 (siCDCA5) on the growth of human OSCC cells. RNAi effect of siCDCA5 was confirmed by Western blotting. Transfection of siCDCA5 suppressed the expression of its target protein in all types of cells. The growth inhibitory effect of siCDCA5 in OSCC cells was evaluated by WST-8 assay. Knockdown of CDCA5 significantly inhibited the growth of OSCC cells in vitro. Subsequently, we analyzed the influence of siCDCA5 on cell cycle by flow cytometry. Suppression of CDCA5 resulted in the decrease in percentage of cells in G0/G1 phase and increase in G2 phase. This indicated that the anti-proliferative effect of siCDCA5 was due to G2 arrest. Furthermore, we investigated the clinical significance of CDCA5 expression in OSCC. The expression of CDCA5 mRNA in tumor and adjacent normal tissues derived from the patient with OSCC was examined by qRT-PCR. Expression levels of CDCA5 mRNA in the OSCC tissues were significantly higher than in normal tissues. We also examined the expression of CDCA5 protein in 80 OSCC cases by immunohistochemistry with anti-CDCA5 antibodies. Tissue expression of CDCA5 was divided into high or low group at 50% stained tumor cells, resulting in 36 cases as high expression and 44 cases as low expression. We then examined the association of CDCA5 expression with various clinicopathological parameters of OSCC patients, and found a significant association between CDCA5 expression levels and pathological staging, metastasis, and recurrence. These results suggest that CDCA5 functions as a critical gene supporting the growth of human OSCC cells and targeting CDCA5 appears a useful therapeutic strategy for the patients with OSCC. Citation Format: Norihiko Tokuzen, Koh-ichi Nakashiro, Hiroshi Tanaka, Yohei Fujita, Kazuki Iwamoto, Hiroyuki Hamakawa. Overexpression and function of CDCA5 in oral squamous cell carcinoma. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 476. doi:10.1158/1538-7445.AM2014-476

Translating bioinformatics in oncology: guilt-by-profiling analysis and identification of KIF18B and CDCA3 as novel driver genes in carcinogenesis.

Co-regulated genes are not identified in traditional microarray analyses, but may theoretically be closely functionally linked [guilt-by-association (GBA), guilt-by-profiling]. Thus, bioinformatics procedures for guilt-by-profiling/association analysis have yet to be applied to large-scale cancer biology. We analyzed 2158 full cancer transcriptomes from 163 diverse cancer entities in regard of their similarity of gene expression, using Pearson's correlation coefficient (CC). Subsequently, 428 highly co-regulated genes (|CC| ≥ 0.8) were clustered unsupervised to obtain small co-regulated networks. A major subnetwork containing 61 closely co-regulated genes showed highly significant enrichment of cancer bio-functions. All genes except kinesin family member 18B (KIF18B) and cell division cycle associated 3 (CDCA3) were of confirmed relevance for tumor biology. Therefore, we independently analyzed their differential regulation in multiple tumors and found severe deregulation in liver, breast, lung, ovarian and kidney cancers, thus proving our GBA hypothesis. Overexpression of KIF18B and CDCA3 in hepatoma cells and subsequent microarray analysis revealed significant deregulation of central cell cycle regulatory genes. Consistently, RT-PCR and proliferation assay confirmed the role of both genes in cell cycle progression. Finally, the prognostic significance of the identified KIF18B- and CDCA3-dependent predictors (P = 0.01, P = 0.04) was demonstrated in three independent HCC cohorts and several other tumors. In summary, we proved the efficacy of large-scale guilt-by-profiling/association strategies in oncology. We identified two novel oncogenes and functionally characterized them. The strong prognostic importance of downstream predictors for HCC and many other tumors indicates the clinical relevance of our findings. Supplementary data are available at Bioinformatics online.

Overexpression of CDCA2 in Human Squamous Cell Carcinoma: Correlation with Prevention of G1 Phase Arrest and Apoptosis

Cell division cycle associated 2 (CDCA2) recruits protein phosphatase 1 to chromatin to antagonize activation of ataxia telangiectasia mutated (ATM)-dependent signal transduction. ATM kinase plays a critical role in the DNA damage response and its phosphorylation cascade to inhibit the p53-MDM2 interaction, which releases p53 to induce p21 and G1 cell-cycle arrest. However, the relevance of CDCA2 to human malignancy including oral squamous cell carcinoma (OSCC) is unknown. In the current study, we found that CDCA2 expression was up-regulated in OSCC cell lines. Functional studies with shRNA system showed that knockdown of CDCA2 significantly (P<0.05) inhibited cellular proliferation compared with the control cells by arresting cell-cycle progression at the G1 phase and up-regulating the cyclin-dependent kinase inhibitors (p21Cip1, p27Kip1, p15INK4B, and p16INK4A). CDCA2 knockdown also promoted apoptosis after treatment with the DNA damage reagent, cisplatin. In clinical samples, the CDCA2 protein expression level in primary OSCCs was significantly (P<0.05) greater than in matched normal oral tissues (67/85, 79%). Furthermore, CDCA2-positive cases were correlated significantly (P<0.05) with high cancer progression. Our results showed for the first time that CDCA2 frequently is overexpressed in OSCCs and might be associated closely with OSCC progression by preventing cell-cycle arrest and apoptosis.

HoxB3 promotes prostate cancer cell progression by transactivating CDCA3

Homeobox (Hox) genes encode homeodomain-containing transcription factors critical to development, differentiation, and homeostasis. Their dysregulation has been implicated in various cancers. In the present study, we show that HoxB3 mRNA and protein are overexpressed in primary prostate cancer tissues compared to the adjacent normal prostate tissues. Moreover, HoxB3 overexpression is associated with higher Gleason grade (⩾7) (P=0.002), clinical stage (P<0.001) and PSA level (⩾10) (P=0.013). The Kaplan and Meier analysis showed that HoxB3 overexpression predicts poor survival outcome. Overexpression of HoxB3 promotes LNCaP cells proliferation and migration in vitro. Furthermore, depletion of HoxB3 in PC-3 cells decreased the capacity of proliferation in a cell division cycle associated 3 (CDCA3)-dependent manner both in vitro and in vivo. The ChIP analysis indicates that HoxB3 can bind to the CDCA3 promoter region and transactivate the CDCA3 expression. These data suggested that HoxB3 promote prostate cancer progression by upregulating CDCA3 expression and may serve as a potential therapeutic target for human prostate cancer.

Genomics and proteomics-based discovery of novel cancer biomarkers and molecular targets for cell-permeable peptide/small molecule-based drugs.

e13552 Background: Identification of cancer-specific oncoproteins is an effective approach to develop new diagnostics and therapeutics. Methods: We have established a strategy as follows to identify new oncoproteins, which can be applied as biomarkers and drug development; i) To identify genes overexpressed in 120 clinical lung cancers using the cDNA microarray representing 27,648 genes, ii) To verify the genes for their low expression in 23 normal tissues by northern-blotting, iii) To validate the clinicopathological significance of their protein expression by tissue microarray covering 262 cases of non-small cell lung cancers (NSCLCs), iv) To verify whether they are essential for the growth of cancer cells by siRNAs, v) To do immunoprecipitation assays and mass-spectrometric analysis to identify their interacting proteins in cancer cells, and screening of cell-permeable peptides that could inhibit the protein-protein interaction that is essential for carcinogenesis. Results: We identified 35 oncoproteins to be upregulated in the majority of lung cancers, and further selected CDCA5 (cell division cycle associated 5) as a good candidate. Tumor tissue microarray analysis of 262 NSCLC patients revealed that CDCA5 positivity was an independent prognostic factor. Suppression of CDCA5 expression with siRNAs inhibited the growth of lung cancer cells; concordantly, induction of exogenous expression of CDCA5 conferred growth-promoting activity in mammalian cells. We also found that extracellular signal-regulated kinase (ERK) kinase interacted with and phosphorylated CDCA5 at Serine 209 in vivo. Functional inhibition of the interaction between CDCA5 and ERK kinase by a cell-permeable peptide corresponding to a 20-amino-acid sequence part of CDCA5, which included the Serine 209 phosphorylation site by ERK, significantly reduced phosphorylation of CDCA5 and resulted in growth suppression of lung cancer cells. Conclusions: CDCA5 positivity should be useful as a novel prognostic biomarker in the clinic. Selective suppression of the ERK-CDCA5 pathway by cell-permeable peptide or small molecule-based drugs could be a promising strategy for cancer therapy.

Phosphorylation and Activation of Cell Division Cycle Associated 5 by Mitogen-Activated Protein Kinase Play a Crucial Role in Human Lung Carcinogenesis

We analyzed the gene expression profiles of clinical lung carcinomas using a cDNA microarray containing 27,648 genes or expressed sequence tags, and identified CDCA5 (cell division cycle associated 5) to be upregulated in the majority of lung cancers. Tumor tissue microarray analysis of 262 non-small cell lung cancer patients revealed that CDCA5 positivity was an independent prognostic factor for lung cancer patients. Suppression of CDCA5 expression with siRNAs inhibited the growth of lung cancer cells; concordantly, induction of exogenous expression of CDCA5 conferred growth-promoting activity in mammalian cells. We also found that extracellular signal-regulated kinase (ERK) kinase phosphorylated CDCA5 at Ser79 and Ser209 in vivo. Exogenous expression of phospho-mimicking CDCA5 protein whose Ser209 residue was replaced with glutamine acid further enhanced the growth of cancer cells. In addition, functional inhibition of the interaction between CDCA5 and ERK kinase by a cell-permeable peptide corresponding to a 20-amino-acid sequence part of CDCA5, which included the Ser209 phosphorylation site by ERK, significantly reduced phosphorylation of CDCA5 and resulted in growth suppression of lung cancer cells. Our data suggest that transactivation of CDCA5 and its phosphorylation at Ser209 by ERK play an important role in lung cancer proliferation, and that the selective suppression of the ERK-CDCA5 pathway could be a promising strategy for cancer therapy.

Phosphorylation and Activation of Cell Division Cycle Associated 8 by Aurora Kinase B Plays a Significant Role in Human Lung Carcinogenesis

Through genome-wide gene expression analysis of lung carcinomas, we detected in the great majority of lung cancer samples cotransactivation of cell division cycle associated 8 (CDCA8) and aurora kinase B (AURKB), which were considered to be components of the vertebrate chromosomal passenger complex. Immunohistochemical analysis of lung cancer tissue microarrays showed that overexpression of CDCA8 and AURKB was significantly associated with poor prognosis of lung cancer patients. AURKB directly phosphorylated CDCA8 at Ser(154), Ser(219), Ser(275), and Thr(278) and seemed to stabilize CDCA8 protein in cancer cells. Suppression of CDCA8 expression with small interfering RNA against CDCA8 significantly suppressed the growth of lung cancer cells. In addition, functional inhibition of interaction between CDCA8 and AURKB by a cell-permeable peptide corresponding to 20-amino acid sequence of a part of CDCA8 (11R-CDCA8(261-280)), which included two phosphorylation sites by AURKB, significantly reduced phosphorylation of CDCA8 and resulted in growth suppression of lung cancer cells. Our data imply that selective suppression of the CDCA8-AURKB pathway could be a promising therapeutic strategy for treatment of lung cancer patients.