BUB1 mRNA is significantly co-expressed with AURKA and AURKB mRNA in advanced-stage ovarian serous carcinoma

A comprehensive review on role of Aurora kinase inhibitors (AKIs) in cancer therapeutics

Aurora kinases (AURKs) are a family of serine /threonine protein kinases that have a crucial role in cell cycle process mainly in the event of chromosomal segregation, centrosome maturation and cytokinesis. The family consists of three members including Aurora kinase A (AURK-A), Aurora kinase B (AURK-B) and Aurora kinase C (AURK-C). All AURKs contain a conserved kinase domain for their activity but differ in their cellular localization and functions. AURK-A and AURK-B are expressed mainly in somatic cells while the expression of AURK-C is limited to germ cells. AURK-A promotes G2 to M transition of cell cycle by controlling centrosome maturation and mitotic spindle assembly. AURK-B and AURK-C form the chromosome passenger complex (CPC) that ensures proper chromosomal alignments and segregation. Aberrant expression of AURK-A and AURK-B has been detected in several solid tumours and malignancies. Hence, they have become an attractive therapeutic target against cancer. The first part of this review focuses on AURKs structure, functions, subcellular localization, and their role in tumorigenesis. The review also highlights the functional and clinical impact of selective as well as pan kinase inhibitors. Currently, >60 compounds that target AURKs are in preclinical and clinical studies. The drawbacks of existing inhibitors like selectivity, drug resistance and toxicity have also been addressed. Since, majority of inhibitors are Aurora kinase inhibitor (AKI) type-1 that bind to the active (DFGin and Cin) conformation of the kinase, this information may be utilized to design highly selective kinase inhibitors that can be combined with other therapeutic agents for better clinical outcomes.

Bioinformatics analysis based on high-throughput sequencing data to identify hub genes related to different clinical types of COVID-19

This article aims to explore hub genes related to different clinical types of cases with COVID-19 and predict the therapeutic drugs related to severe cases. The expression profile of GSE166424 was divided into four data sets according to different clinical types of COVID-19 and then calculated the differential expression genes (DEGs). The specific genes of four clinical types of COVID-19 were obtained by Venn diagram and conducted enrichment analysis, protein-protein interaction (PPI) networks analysis, screening hub genes, and ROC curve analysis. The hub genes related to severe cases were verified in GSE171110, their RNA-specific expression tissues were obtained from the HPA database, and potential therapeutic drugs were predicted through the DGIdb database. There were 536, 266, 944, and 506 specific genes related to asymptomatic infections, mild, moderate, and severe cases, respectively. The hub genes of severe specific genes were AURKB, BRCA1, BUB1, CCNB1, CCNB2, CDC20, CDC6, KIF11, TOP2A, UBE2C, and RPL11, and also differentially expressed in GSE171110 (P < 0.05), and their AUC values were greater than 0.955. The RNA tissue specificity of AURKB, CDC6, KIF11, UBE2C, CCNB2, CDC20, TOP2A, BUB1, and CCNB1 specifically enhanced on lymphoid tissue; CCNB2, CDC20, TOP2A, and BUB1 specifically expressed on the testis. Finally, 55 drugs related to severe COVID-19 were obtained from the DGIdb database. Summary, AURKB, BRCA1, BUB1, CCNB1, CCNB2, CDC20, CDC6, KIF11, TOP2A, UBE2C, and RPL11 may be potential diagnostic biomarkers for severe COVID-19, which may affect immune and male reproductive systems. 55 drugs may be potential therapeutic drugs for severe COVID-19.

Comprehensive analysis identifies as a critical prognostic prediction gene in breast cancer

BACKGROUND

Aurora kinases (AURKs) family plays a vital role not only in cell division but also in tumorigenesis. However, there are still rare systematic analyses of the diverse expression patterns and prognostic value of the AURKs family in breast cancer (BC). Systematic bioinformatics analysis was conducted to explore the biological role, prognostic value, and immunologic function of AURKs family in BC.

METHODS

The expression, prognostic value, and clinical functions of AURKs family in BC were evaluated with several bioinformatics web portals: ONCOMINE Gene Expression Profiling Interactive Analysis, Kaplan-Meier plotter, cBioPortal, Metascape, GeneMANIA, and LinkedOmics; and the result was verified using human tissues.

RESULTS

The expression of AURKA and AURKB were upregulated in BC in subgroup analyses based on tumor stage (all P   <  0.05). BC patients with high AURKA and AURKB expression had a worse overall survival, relapse-free survival, and distant metastasis-free survival (all P   <  0.05). Verification experiment revealed that AURKA and AURKB were upregulated in BC ( P  < 0.05). AURKA and AURKB were specifically associated with several tumor-associated kinases (polo-like kinase 1 and cyclin-dependent kinase 1), miRNAs (miR-507 and miR-381), and E2F transcription factor 1. Moreover, AURKA and AURKB were correlated with immune cell infiltration. Functional enrichment analysis revealed that AURKA and AURKB were involved in the cell cycle signaling pathway, platinum drug resistance signaling pathway, ErbB signaling pathway, Hippo signaling pathway, and nucleotide-binding and oligomerization domain-like receptor signaling pathway.

CONCLUSIONS

Aurora kinases AURKA and AURKB could be employed as novel prognostic biomarkers or promising therapeutic targets for BC.

Identification of keygenes, miRNAs and miRNA-mRNA regulatory pathways for chemotherapy resistance in ovarian cancer

Background

Chemotherapy resistance, especially platinum resistance, is the main cause of poor prognosis of ovarian cancer. It is of great urgency to find molecular markers and mechanism related to platinum resistance in ovarian cancer.

Methods

One mRNA dataset (GSE28739) and one miRNA dataset (GSE25202) were acquired from Gene Expression Omnibus (GEO) database. The GEO2R tool was used to screen out differentially expressed genes (DEGs) and differentially expressed miRNAs (DE-miRNAs) between platinum-resistant and platinum-sensitive ovarian cancer patients. Gene Ontology (GO) function and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis for DEGs were performed using the DAVID to present the most visibly enriched pathways. Protein–protein interaction (PPI) of these DEGs was constructed based on the information of the STRING database. Hub genes related to platinum resistance were visualized by Cytoscape software. Then, we chose seven interested hub genes to further validate using qRT-PCR in A2780 ovarian cancer cell lines. And, at last, the TF-miRNA-target genes regulatory network was predicted and constructed using miRNet software.

Results

A total of 63 upregulated DEGs, 124 downregulated DEGs, four upregulated miRNAs and six downregulated miRNAs were identified. From the PPI network, the top 10 hub genes were identified, which were associated with platinum resistance. Our further qRT-PCR showed that seven hub genes (BUB1, KIF2C, NUP43, NDC80, NUF2, CCNB2 and CENPN) were differentially expressed in platinum-resistant ovarian cancer cells. Furthermore, the upstream transcription factors (TF) for upregulated DE-miRNAs were SMAD4, NFKB1, SMAD3, TP53 and HNF4A. Three overlapping downstream target genes (KIF2C, STAT3 and BUB1) were identified by miRNet, which was regulated by hsa-miR-494.

Conclusions

The TF-miRNA–mRNA regulatory pairs, that is TF (SMAD4, NFKB1 and SMAD3)-miR-494-target genes (KIF2C, STAT3 and BUB1), were established. In conclusion, the present study is of great significance to find the key genes of platinum resistance in ovarian cancer. Further study is needed to identify the mechanism of these genes in ovarian cancer.

Current progress, challenges and future prospects of indazoles as protein kinase inhibitors for the treatment of cancer

The indazole core is an interesting pharmacophore due to its applications in medicinal chemistry. In the past few years, this moiety has been used for the synthesis of kinase inhibitors. Many researchers have demonstrated the use of indazole derivatives as specific kinase inhibitors, including tyrosine kinase and serine/threonine kinases. A number of anticancer drugs with an indazole core are commercially available, e.g. axitinib, linifanib, niraparib, and pazopanib. Indazole derivatives are applied for the targeted treatment of lung, breast, colon, and prostate cancers. In this review, we compile the current development of indazole derivatives as kinase inhibitors and their application as anticancer agents in the past five years.

Aurora B kinase: a potential drug target for cancer therapy

BACKGROUND

Ensuring genetic integrity is essential during the cell cycle to avoid aneuploidy, one of the underlying causes of malignancies. Aurora kinases are serine/threonine kinase that play a vital role in maintaining the genomic integrity of the cells. There are three forms of aurora kinases in the mammalian cells, which are highly conserved and act together with several other proteins to control chromosome alignment and its equal distribution to daughter cells in mitosis and meiosis.

METHODS

We provide here a detailed analysis of Aurora B kinase (ABK) in terms of its expression, structure, function, disease association and potential therapeutic implications.

RESULTS

ABK plays an instrumental in mitotic entry, chromosome condensation, spindle assembly, cytokinesis, and abscission. Small-molecule inhibitors of ABK are designed and synthesized to control cancer progression. A detailed understanding of ABK pathophysiology in different cancers is of great significance in designing and developing effective therapeutic strategies.

CONCLUSION

In this review, we have discussed the physiological significance of ABK followed by its role in cancer progression. We further highlighted available small-molecule inhibitors to control the tumor proliferation and their mechanistic insights.

Aurora kinase inhibitors as potential anticancer agents: Recent advances

Aurora kinases are a family of serine/threonine kinases that play a crucial role in cell proliferation through the regulation of mitotic spindles. These kinases are the regulatory proteins localized in the various phases of the cell cycle and are involved in centrosome maturation, chromosome alignment, chromosomal segregation, and cytokinesis. They have emerged as one of the validated drug targets for anticancer drug discovery as their overexpression has been implicated in the pathogenesis of various carcinomas. Inhibitors of Aurora kinases induce growth inhibition and apoptosis in a variety of tumor cells. Hence, the design and development of Aurora kinase inhibitors have been widely explored in recent years by the scientific community as potential anticancer agents. Various Aurora kinase inhibitors have been under preclinical and clinical investigations as antitumor agents. This review summarizes the recent strategies of various researchers for the design and development of Aurora kinase inhibitors belonging to different structural classes. Their bioactivity, SARs, molecular modelling, and mechanistic studies have also been described. The comprehensive compilation of research work carried out in the field will provide inevitable scope for the design and development of novel drug candidates with better selectivity and efficacy. The review is constructed after the exhaustive research in this discipline and includes the papers from 2011 to 2020.

Differential expression of lung adenocarcinoma transcriptome with signature of tobacco exposure

Smoking accounts for almost 80-90% of lung cancer cases, which is also the most frequent cause of cancer-related deaths in humans. With over 60 carcinogens in tobacco smoke, cells dividing at the time of carcinogen exposure are at particular risk of neoplasia. The present study aimed to investigate global gene expression differences in lung adenocarcinoma (LUAD) tumour samples of current smokers and non-smokers, in an attempt to elucidate biological mechanisms underlying divergent smoking effects. Current and non-smoker tumour samples were analysed using bioinformatics tools, examining differences in molecular drivers of cancer initiation and progression, as well as evaluating the effect of smoking and sex on epithelial mesenchymal transition (EMT). As a result, we identified 1150 differentially expressed genes showing visible differences in the expression profiles between the smoking subgroups. The genes were primarily involved in cell cycle, DNA replication, DNA repair, VEGF, GnRH, ErbB and T cell receptor signalling pathways. Our results show that smoking clearly affected E2F transcriptional activity and DNA repair pathways including mismatch repair, base excision repair and homologous recombination. We observed that sex could modify the effects of PLA2G2A and PRG4 in LUAD tumour samples, whereas sex and smoking status might possibly have a biological effect on the EMT-related genes: HEY2, OLFM1, SFRP1 and STRAP. We also identified potential epigenetic changes smoking solely might have on EMT-related genes, which may serve as potential diagnostic and prognostic biomarkers for LUAD patients.

Bioinformatics Analysis of Global Proteomic and Phosphoproteomic Data Sets Revealed Activation of NEK2 and AURKA in Cancers

Tumor heterogeneity attributes substantial challenges in determining the treatment regimen. Along with the conventional treatment, such as chemotherapy and radiotherapy, targeted therapy has greater impact in cancer management. Owing to the recent advancements in proteomics, we aimed to mine and re-interrogate the Clinical Proteomic Tumor Analysis Consortium (CPTAC) data sets which contain deep scale, mass spectrometry (MS)-based proteomic and phosphoproteomic data sets conducted on human tumor samples. Quantitative proteomic and phosphoproteomic data sets of tumor samples were explored and downloaded from the CPTAC database for six different cancers types (breast cancer, clear cell renal cell carcinoma (CCRCC), colon cancer, lung adenocarcinoma (LUAD), ovarian cancer, and uterine corpus endometrial carcinoma (UCEC)). We identified 880 phosphopeptide signatures for differentially regulated phosphorylation sites across five cancer types (breast cancer, colon cancer, LUAD, ovarian cancer, and UCEC). We identified the cell cycle to be aberrantly activated across these cancers. The correlation of proteomic and phosphoproteomic data sets identified changes in the phosphorylation of 12 kinases with unchanged expression levels. We further investigated phosphopeptide signature across five cancer types which led to the prediction of aurora kinase A (AURKA) and kinases-serine/threonine-protein kinase Nek2 (NEK2) as the most activated kinases targets. The drug designed for these kinases could be repurposed for treatment across cancer types.

Overexpression of PRC1 indicates a poor prognosis in ovarian cancer

Protein regulator of cytokinesis-1 (PRC1) is a microtubule-associated factor involved in cytokinesis. Recent studies have indicated that PRC1 overexpression is involved in tumorigenesis in multiple types of human cancer. However, the expression, biological functions and the prognostic significance of PRC1 in ovarian cancer have not yet been clarified. In this study, it was confirmed that the PRC1 mRNA and protein expression levels were upregulated in high-grade serous ovarian carcinoma (HGSOC) tissues, particularly in patients without breast cancer susceptibility gene (BRCA) pathogenic mutations. PRC1 overexpression contributed to drug resistance, tumor recurrence and a poor prognosis. The findings also indicated that PRC1 knockdown decreased the proliferation, metastasis and multidrug resistance of ovarian cancer cells in vitro. It was also demonstrated that forkhead box protein M1 (FOXM1) regulated the mRNA and protein expression of PRC1. Dual-luciferase reporter assay and rescue assay confirmed that PRC1 was a direct crucial downstream target of FOXM1. On the whole, the findings of this study confirmed that PRC1 was a major prognostic factor of HGSOC and a promising therapeutic biomarker for the treatment of ovarian cancer.

AURKB Promotes the Metastasis of Gastric Cancer, Possibly by Inducing EMT

AIM

To investigate the function of Aurora kinase B (AURKB) in gastric cancer (GC).

METHODS

Immunohistochemistry was used to assay the expression of AURKB in 50 pairs of GC and adjacent tissues, and qRT-PCR was conducted to test AURKB expression in normal gastric epithelial and GC cell lines. Two segments of small interference RNAs (siRNAs) targeting AURKB were synthesized and inserted into GV248 lentivirus vector. After transfected with LV-AURKB-RNAis, CCK8, wound healing, transwell and flow cytometric assays were performed to determine the influence of silencing AURKB on cell proliferation, invasion, migration, cell cycles and apoptosis of GC cells, and the expression of EMT (epithelial-mesenchymal transition)-related markers was demonstrated by Western blots (WB).

RESULTS

AURKB was highly expressed in GC and closely associated with lymph node metastasis and advanced stages of GC. Down-regulating AURKB suppressed the proliferation and promoted the apoptosis of GC cells, arrested the cell cycle in G2/M phase, and inhibited the invasion and migration of GC cells. The expression levels of AKT1, mTOR, Myc, MMP2, and VEGFA were decreased, while the expression levels of OCLN and JUP were increased after knocking down of AURKB in both AGC and MKN45 cells.

CONCLUSION

AURKB is overexpressed in GC and closely associated with clinicopathologic characteristics of GC. It is likely that by inhibiting VEGFA/Akt/mTOR and Wnt/β-catenin/Myc pathways, silenced AURKB could inhibit the invasive and migratory abilities of GC cells. However, because of the small sample size and the absence of in-vivo experiments, these results should be verified by further studies.

Quantitative Proteomics of Th-MYCN Transgenic Mice Reveals Aurora Kinase Inhibitor Altered Metabolic Pathways and Enhanced ACADM To Suppress Neuroblastoma Progression

Neuroblastoma is a neural crest-derived embryonal tumor and accounts for about 15% of all cancer deaths in children. MYCN amplification is associated with aggressive and advanced stage of high-risk neuroblastoma, which remains difficult to treat and exhibits poor survival under current multimodality treatment. Here, we analyzed the transcriptomic profiles of neuroblastoma patients and showed that aurora kinases lead to poor survival and had positive correlation with MYCN amplification and high-risk disease. Further, pan-aurora kinase inhibitor (tozasertib) treatment not only induces cell-cycle arrest and suppresses cell proliferation, migration, and invasion ability in MYCN-amplified (MNA) neuroblastoma cell lines, but also inhibits tumor growth and prolongs animal survival in Th-MYCN transgenic mice. Moreover, we performed quantitative proteomics and identified 150 differentially expressed proteins after tozasertib treatment in the Th-MYCN mouse model. The functional and network-based enrichment revealed that tozasertib alters metabolic processes and identified a mitochondrial flavoenzyme in fatty acid β-oxidation, ACADM, which is correlated with aurora kinases and neuroblastoma patient survival. Our findings indicate that the aurora kinase inhibitor could cause metabolic imbalance, possibly by disturbing carbohydrate and fatty acid metabolic pathways, and ACADM may be a potential target in MNA neuroblastoma.

Study of Gene Expression Profiles of Breast Cancers in Indian Women

Breast cancer is the most common cancer among women globally. In India, the incidence of breast cancer has increased significantly during the last two decades with a higher proportion of the disease at a young age compared to the west. To understand the molecular processes underlying breast cancer in Indian women, we analysed gene expression profiles of 29 tumours and 9 controls using microarray. In the present study, we obtained 2413 differentially expressed genes, consisting of overexpressed genes such as COL10A1, COL11A1, MMP1, MMP13, MMP11, GJB2, and CST1 and underexpressed genes such as PLIN1, FABP4, LIPE, AQP7, LEP, ADH1A, ADH1B, and CIDEC. The deregulated pathways include cell cycle, focal adhesion and metastasis, DNA replication, PPAR signaling, and lipid metabolism. Using PAM50 classifier, we demonstrated the existence of molecular subtypes in Indian women. In addition, qPCR validation of expression of metalloproteinase genes, MMP1, MMP3, MMP11, MMP13, MMP14, ADAMTS1, and ADAMTS5 showed concordance with that of the microarray data; wherein we found a significant association of ADAMTS5 down-regulation with older age (≥55 years) of patients. Together, this study reports gene expression profiles of breast tumours from the Indian subcontinent, throwing light on the pathways and genes associated with the breast tumourigenesis in Indian women.

Methylation-mediated repression of MiR-424/503 cluster promotes proliferation and migration of ovarian cancer cells through targeting the hub gene KIF23

Ovarian cancer is one type of gynecological malignancies with extremely high lethal rate. Abnormal proliferation and metastasis are regarded to play important roles in patients' death, whereas we know little about the underlying molecular mechanisms. Under this circumstance, our current study aims to investigate the role of hub genes in ovarian cancer. Bioinformatics analysis of the data from GEO and analyses of ovarian cancer samples were performed. Then, the results showed that KIF23, a hub gene, was mainly related to cell cycle and positively associated with poor prognosis. Meanwhile, both miR-424-5p and miR-503-5p directly targeted to 3'UTR of KIF23 to suppress the expression of KIF23 and inhibit ovarian cancer cell proliferation and migration. Furthermore, we discovered that miR-424/503 was epigenetically repressed by hypermethylation in the promoter regions, which directly modulated the expression of KIF23 to improve the oncogenic performance of cancer cells in vitro. Together, our research certifies that miR-424/503 cluster is silenced by DNA hypermethylation, which promotes the expression of KIF23, thereby regulating the proliferation and migration of ovarian cancer cells. Interposing this process might be a novel approach in cancer therapy.

A five-gene signature predicts overall survival of patients with papillary renal cell carcinoma

Background

The present study aims to investigate the gene expression changes in papillary renal cell carcinoma(pRCC) and screen several genes and associated pathways of papillary renal cell carcinoma progression.

Methods

The papillary renal cell carcinoma RNA sequencing (RNA-seq) data set was downloaded from TCGA (The Cancer Genome Atlas). We identified the differentially expressed mRNAs between cancer and normal tissues and performed annotation of differentially expressed mRNAs to figure out the functions and pathways they were enriched in. Then, we constructed a risk score that relied on the 5-mRNA. The optimal value for the patients’classification risk level was identified by ROC analysis. The relationship between mRNA expression and prognosis of papillary renal cell carcinoma was evaluated by univariate Cox regression model. The 5-mRNA based risk score was validated in both complete set and testing set.

Result

In general, the 5-mRNA (CCNB2, IGF2BP3, KIF18A, PTTG1, and BUB1) were identified and validated, which can predict papillary renal cell carcinoma patient survival. This study revealed the 5-mRNA expression profile and the potential function of a single mRNA as a prognostic target for papillary renal cell carcinoma.

Conclusion

In addition, these findings may have significant implications for potential treatments options and prognosis for patients with papillary renal cell carcinoma.

Natural products as new antimitotic compounds for anticancer drug development

Cell cycle control genes are frequently mutated in cancer cells, which usually display higher rates of proliferation than normal cells. Dysregulated mitosis leads to genomic instability, which contributes to tumor progression and aggressiveness. Many drugs that disrupt mitosis have been studied because they induce cell cycle arrest and tumor cell death. These antitumor compounds are referred to as antimitotics. Vinca alkaloids and taxanes are natural products that target microtubules and inhibit mitosis, and their derivatives are among the most commonly used drugs in cancer therapy worldwide. However, severe adverse effects such as neuropathies are frequently observed during treatment with microtubule-targeting agents. Many efforts have been directed at developing improved antimitotics with increased specificity and decreased likelihood of inducing side effects. These new drugs generally target specific components of mitotic regulation that are mainly or exclusively expressed during cell division, such as kinases, motor proteins and multiprotein complexes. Such small molecules are now in preclinical studies and clinical trials, and many are products or derivatives from natural sources. In this review, we focused on the most promising targets for the development of antimitotics and discussed the advantages and disadvantages of these targets. We also highlighted the novel natural antimitotic agents under investigation by our research group, including combretastatins, withanolides and pterocarpans, which show the potential to circumvent the main issues in antimitotic therapy.

Bioinformatics analysis of key differentially expressed genes in well and poorly differentiated endometrial carcinoma

Endometrial carcinoma (EC) is one of the most common gynecological malignancies. The malignant degree increases between grade (G)1 and G3, and EC of G3 usually presents a high recurrence rate and poor prognosis. Therefore, the present study aimed to examine the principal genes associated with the degree of differentiation in EC. The microarrays GSE17025, GSE24537 and GSE35784, representing data of Type I EC samples of G1 and G3, were downloaded from the Gene Expression Omnibus. The differentially expressed genes (DEGs) and differentially expressed micro (mi)RNAs (DEMs) were identified, followed by functional enrichment analyses and interaction network construction. In total, 83 upregulated and 130 downregulated DEGs with the same expression trends in two mRNA datasets were screened. The upregulated DEGs were primarily enriched in 'mitotic cell cycle process', 'cell cycle process' and 'mitotic cell cycle'; while the downregulated DEGs were enriched in 'cellular component assembly involved in morphogenesis', 'cell projection organization' and 'microtubule‑based movement'. From the protein‑protein interaction network, DNA topoisomerase IIα, kinesin family member 11, cyclin B1 and BUB1 mitotic checkpoint serine/threonine were identified as foremost hub genes. One module was extracted and involved in 'mitotic cell cycle process' and 'cell cycle process'. Based on the analysis of DEMs and the miRNA‑target regulatory network, miRNA‑9 may be the most important upregulated DEM, and the DEGs forkhead box P1 and cyclin E1 may serve vital roles in the differentiation of EC. In conclusion, principal genes were identified that may be determinants of the carcinogenesis of poorly differentiated EC, which may facilitate the examination of potential molecular mechanisms. These genes may additionally help identify candidate biomarkers and novel therapeutic targets for poorly differentiated EC.

Identifying biomarkers of papillary renal cell carcinoma associated with pathological stage by weighted gene co-expression network analysis

Although papillary renal cell carcinoma (PRCC) accounts for 10%–15% of renal cell carcinoma (RCC), no predictive molecular biomarker is currently applicable to guiding disease stage of PRCC patients. The mRNASeq data of PRCC and adjacent normal tissue in The Cancer Genome Atlas was analyzed to identify 1148 differentially expressed genes, on which weighted gene co-expression network analysis was performed. Then 11 co-expressed gene modules were identified. The highest association was found between blue module and pathological stage (r = 0.45) by Pearson's correlation analysis. Functional enrichment analysis revealed that biological processes of blue module focused on nuclear division, cell cycle phase, and spindle (all P < 1e-10). All 40 hub genes in blue module can distinguish localized (pathological stage I, II) from non-localized (pathological stage III, IV) PRCC (P < 0.01). A good molecular biomarker for pathological stage of RCC must be a prognostic gene in clinical practice. Survival analysis was performed to reversely validate if hub genes were associated with pathological stage. Survival analysis unveiled that all hub genes were associated with patient prognosis (P < 0.01). The validation cohort GSE2748 verified that 30 hub genes can differentiate localized from non-localized PRCC (P < 0.01), and 18 hub genes are prognosis-associated (P < 0.01).

ROC curve indicated that the 17 hub genes exhibited excellent diagnostic efficiency for localized and non-localized PRCC (AUC > 0.7). These hub genes may serve as a biomarker and help to distinguish different pathological stages for PRCC patients.

G2/M inhibitors as pharmacotherapeutic opportunities for glioblastoma: the old, the new, and the future

Glioblastoma (GBM) is one of the deadliest tumors and has a median survival of 3 months if left untreated. Despite advances in rationally targeted pharmacological approaches, the clinical care of GBM remains palliative in intent. Since the majority of altered signaling cascades involved in cancer establishment and progression eventually affect cell cycle progression, an alternative approach for cancer therapy is to develop innovative compounds that block the activity of crucial molecules needed by tumor cells to complete cell division. In this context, we review promising ongoing and future strategies for GBM therapeutics aimed towards G2/M inhibition such as anti-microtubule agents and targeted therapy against G2/M regulators like cyclin-dependent kinases, Aurora inhibitors, PLK1, BUB, 1, and BUBR1, and survivin. Moreover, we also include investigational agents in the preclinical and early clinical settings. Although several drugs were shown to be gliotoxic, most of them have not yet entered therapeutic trials. The use of either single exposure or a combination with novel compounds may lead to treatment alternatives for GBM patients in the near future.

Aurora kinases: novel therapy targets in cancers

Aurora kinases, a family of serine/threonine kinases, consisting of Aurora A (AURKA), Aurora B (AURKB) and Aurora C (AURKC), are essential kinases for cell division via regulating mitosis especially the process of chromosomal segregation. Besides regulating mitosis, Aurora kinases have been implicated in regulating meiosis. The deletion of Aurora kinases could lead to failure of cell division and impair the embryonic development. Overexpression or gene amplification of Aurora kinases has been clarified in a number of cancers. And a growing number of studies have demonstrated that inhibition of Aurora kinases could potentiate the effect of chemotherapies. For the past decades, a series of Aurora kinases inhibitors (AKIs) developed effectively repress the progression and growth of many cancers both in vivo and in vitro, suggesting that Aurora kinases could be a novel therapeutic target. In this review, we'll first briefly present the structure, localization and physiological functions of Aurora kinases in mitosis, then describe the oncogenic role of Aurora kinases in tumorigenesis, we shall finally discuss the outcomes of AKIs combination with conventional therapy.

Wee1 is a novel independent prognostic marker of poor survival in post-chemotherapy ovarian carcinoma effusions

OBJECTIVE

Wee1-like kinase (Wee1) is a tyrosine kinase which negatively regulates entry into mitosis at the G2 to M-phase transition and has a role in inhibition of unscheduled DNA replication in S-phase. The present study investigated the clinical role of Wee1 in advanced-stage (FIGO III-IV) ovarian serous carcinoma.

METHODS

Wee1 protein expression was analyzed in 287 effusions using immunohistochemistry. Expression was analyzed for association with clinicopathologic parameters, including survival. Forty-five effusions were additionally studied using Western blotting. Wee1 was further silenced in SKOV3 and OVCAR8 cells by siRNA knockdown and proliferation was assessed.

RESULTS

Nuclear expression of Wee1 in tumor cells was observed in 265/287 (92%) and 45/45 (100%) effusions by immunohistochemistry and Western blotting, respectively. Wee1 expression by immunohistochemistry was significantly higher in post-chemotherapy disease recurrence compared to pre-chemotherapy effusions obtained at diagnosis (p=0.002). Wee1 silencing in SKOV3 and OVCAR8 cells reduced proliferation. In univariate survival analysis of the entire cohort, a trend was observed between high (>25% of cells) Wee1 expression and poor overall survival (p=0.083). Survival analysis for 109 patients with post-chemotherapy effusions showed significant association between Wee1 expression and poor overall survival (p=0.004), a finding which retained its independent prognostic role in Cox multivariate analysis (p=0.003).

CONCLUSIONS

Wee1 is frequently expressed in ovarian serous carcinoma effusions, and its expression is significantly higher following exposure to chemotherapy. The present study is the first to report that Wee1 is an independent prognostic marker in serous ovarian carcinoma.