AURKB promotes gastric cancer progression via activation of CCND1 expression.
ABSTRACT: Aurora kinase B (AURKB) triggers the phosphorylation of serine 10 on histone H3 (H3S10ph), which is important for chromosome condensation and cytokinesis during mitosis in mammals. However, how exactly AURKB controls cell cycle and contributes to tumorigenesis as an oncoprotein under pathological conditions remains largely unknown. Here, we report that AURKB promotes gastric cancer cell proliferation in vitro and in vivo. Silencing AURKB expression inhibits gastric cell proliferation and arrests the cell cycle in G2/M phase. We demonstrate that cyclin D1 (CCND1) is a direct downstream target of AURKB that plays a key role in gastric cancer cell proliferation. AURKB is able to activate the expression of CCND1 through mediating H3S10ph in the promoter of the CCND1 gene. Furthermore, we show that AZD1152, a specific inhibitor of AURKB, can suppress the expression of CCND1 in the gastric cancer cells and inhibit cell proliferation in vitro and in vivo. Importantly, we found that high AURKB and CCND1 expression levels are correlated with shorter overall survival of gastric cancer patients. This study demonstrates that AURKB promotes gastric tumorigenesis potentially through epigenetically activating CCND1 expression, suggesting AURKB as a promising therapeutic target in gastric cancer.
Project description: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/?-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.
Project description:Background:Aurora kinase B (AURKB) is an important carcinogenic factor in various tumors, while its role in clear cell renal cell carcinoma (ccRCC) still remains unclear. This study aimed to investigate its prognostic value and mechanism of action in ccRCC. Methods:Gene expression profiles and clinical data of ccRCC patients were downloaded from The Cancer Genome Atlas database. R software was utilized to analyze the expression and prognostic role of AURKB in ccRCC. Gene set enrichment analysis (GSEA) was used to analyze AURKB related signaling pathways in ccRCC. Results:AURKB was expressed at higher levels in ccRCC tissues than normal kidney tissues. Increased AURKB expression in ccRCC correlated with high histological grade, pathological stage, T stage, N stage and distant metastasis (M stage). Kaplan-Meier survival analysis suggested that high AURKB expression patients had a worse prognosis than patients with low AURKB expression levels. Multivariate Cox analysis showed that AURKB expression is a prognostic factor of ccRCC. GSEA indicated that genes involved in autoimmune thyroid disease, intestinal immune network for IgA production, antigen processing and presentation, cytokine-cytokine receptor interaction, asthma, etc., were differentially enriched in the AURKB high expression phenotype. Conclusions:AURKB is a promising biomarker for predicting prognosis of ccRCC patients and a potential therapeutic target. In addition, AURKB might regulate progression of ccRCC through modulating intestinal immune network for IgA production and cytokine-cytokine receptor interaction, etc. signaling pathways. However, more research is necessary to validate the findings.
Project description:Stress granules are small RNA-protein granules that modify the translational landscape during cellular stress to promote survival. The RhoGTPase RhoA is implicated in the formation of RNA stress granules. Our data demonstrate that the cytokinetic proteins ECT2 and AurkB are localized to stress granules in human astrocytoma cells. AurkB and its downstream target histone-3 are phosphorylated during arsenite-induced stress. Chemical (AZD1152-HQPA) and siRNA inhibition of AurkB results in fewer and smaller stress granules when analyzed utilizing high throughput fluorescent based cellomics assays. RNA immunoprecipitation with the known stress granule aggregates TIAR and G3BP1 was performed on astrocytoma cells and subsequent analysis revealed that astrocytoma stress granules harbour unique mRNAs for various cellular pathways including cellular migration, metabolism, translation and transcriptional regulation. Human astrocytoma cell stress granules contain mRNA that are known to be involved in glioma signaling and the mTOR pathway. These data provide evidence that RNA stress granules are a novel form of epigenetic regulation in astrocytoma cells, which may be targetable by chemical inhibitors and enhance astrocytoma susceptiblity to conventional therapy such as radiation and chemotherapy. Astrocytoma cells were either untreated or treated with arsenite to induce stress granule formation and RNA immunoprecipitates were analyzed by exon array analysis. RNA species that were enriched in TIAR RIPs and G3BP1 RIPS, respectively were compared to compared to TIAR and G3BP1 RIPs from untreated cells and input controls. Ingenuity pathway analysis was performed on the stress granule enriched mRNAs from the TIAR and G3BP1 RIPs to identify significant functional biology networks.
Project description:Background:The modification and regulation of N6-methyladenosine (m6A) at mRNA level can affect the development and progression in various tumors. ALKBH5, as an m6A demethylase, plays different roles in tumors by regulating the m6A modification of mRNA. However, its role in renal cell carcinoma (RCC) remains unclear. Methods:First, levels of ALKBH5 in RCC tissues and cell lines were verified by qRT-PCR and western blot. We analyzed the relationship between ALKBH5 and the clinicopathological characteristics of RCC patients and the influence of ALKBH5 on the prognosis of patients. Then we generated ALBKH5-overexpression, ALBKH5-knockdown stable RCC cell lines and their control cell lines. Through cell proliferation assay, colony formation assay, cell invasion and tumor migration assay, cell cycle assay and xenograft studies, we studied the ALKBH5 roles in RCC cell lines. AURKB was predicted to be its potential target based on TCGA database analysis and verified by western blot. The role of AURKB in RCC was verified by TCGA database and Kaplan-Meier analysis with TMA immunohistochemical analysis. Finally, the specific molecular mechanism of ALKBH5 targeting AURKB was explored by dual-luciferase reporter assay, RNA immunoprecipitation (RIP), m6A dot-blot assay, m6A RNA Immunoprecipitation (MeRIP) assay, and mRNA stability assay. Results:We found that ALKBH5 was highly expressed in both RCC tumor tissues and cell lines. Clinicopathological analysis showed that high ALKBH5 expression was associated with larger tumor volume (P=0.017) and higher TNM staging (P=0.006), and worse prognosis (log rank: P=0.0199). The cellular functional assays showed that stably overexpression ALKBH5 could promote the cell proliferation, colony formation, cell migration and cell invasion of renal cell carcinoma cells in vitro and promote tumor growth in vivo. In contrast, ALKBH5 knocked down inhibited cell proliferation, colony formation, migration and invasion of renal cell carcinoma cells in vitro. Based on TCGA database analysis, AURKB was predicted highly expressed in RCC and a potential target of ALKBH5. Both database prediction and TMA immunohistochemical analysis supported that AURKB could affect the prognosis of RCC patients (P values of 5.5e-08 and 0.0004, respectively) and was regulated by ALKBH5 expression level. Subsequent mechanism experiments showed that ALKBH5 regulated the expression of AURKB by regulating the stability of AURKB mRNA in the m6A-dependent manner, and finally promoted cell proliferation. Furthermore, we found that hypoxia-induced HIF could up-regulate both expressions of AURKB and ALKBH5. Conclusions:Our findings suggest that ALKBH5 may play a carcinogenic role in renal cell carcinoma by stabilizing AURKB mRNA in a m6A-dependent manner. These data suggest that ALKBH5 may play a key role in RCC and targeting the ALKBH5 signaling pathway may be a promising strategy for the treatment of RCC.
Project description:Background:New therapeutic drug for breast cancer (BRCA), especially triple negative BRCA (TNBC), is urgently needed. Even though 2-(4-morpholinoanilino)-6-cyclohexylaminopurine (reversine) is an aurora kinase inhibitor, it also inhibits some cancer cells and human BRCA cells. However, the potential roles of reversine as a novel therapeutic agent for the treatment of BRCA remains unknown and must be further investigation. Thus, the relationship of reversine to aurora kinase in BCRA has not been reported. The relationship between AURKB and survival rate in BRCA has never been reported. Herein, we tested the roles of reversine on different BRCA cell line subtypes. We also investigated the relationship between AURKB and survival rate in BRCA as well as reversine to Aurora kinase expression in BCRA cell lines, including TNBC subtype, 4T1, MDA-MB-231, and luminal subtype MCF-7. Methods:Cell viability and apoptosis were detected using Cell Counting Kit-8 and flow cytometry analysis, respectively. Apoptotic and tumor-related proteins were tested using Western blot analysis. Important microRNAs that regulate BRCA were analyzed using RT-PCR. UALCAN public databases were used to analyze the targeted gene profiles, and the PROGgeneV2 database was used to study the prognostic implications of genes. Results:Reversine inhibits cell proliferation and induces cell apoptosis by modulating caspase-3 and bax/bcl-2 among the three cell lines. Data from the UALCAN public database show that BRCA tissues expressed high gene levels of AURKB, TIMP1, MMP9, and TGFB1 compared with the normal tissue. Among the over-expressed genes in BRCA, AURKB ranks 9th in TNBC, 49th in luminal subtype, and 48th in HER2 subtype. High AURKB level in BRCA is highly related to the low survival rate in patients displayed in 18 databases searched via PROGgeneV2. The protein levels of aurora B kinase (Aurora B), which is encoded by AURKB gene, are highly suppressed by reversine in the three cell lines. The tumor-related proteins TGF-?1, TIMP1, and MMP9 are partially suppressed by reversine but with different sensitivity in the three cell lines. The reversine-affected microRNAs, such as miR129-5p, miR-199a-3p, and miR-3960, in MDA-MB-231 cell line might be the research targets in TNBC regulation. Conclusions:In BRCA, the level of AURKB are over-expressed and is related to low survival rate. Reversine contributes to anti-growth effect in BRCA cell lines, especially for TNBC, by modulating the aurora B. However, the invasiveness, metastasis, and anti-tumor effects of reversine in vivo and in vitro must be further investigated.
Project description:Benign melanocytic nevi frequently emerge when an acquired <i>BRAF<sup>V600E</sup></i> mutation triggers unchecked proliferation and subsequent arrest in melanocytes. Recent observations have challenged the role of oncogene-induced senescence in melanocytic nevus formation, necessitating investigations into alternative mechanisms for the establishment and maintenance of proliferation arrest in nevi. We compared the transcriptomes of melanocytes from healthy human skin, nevi, and melanomas arising from nevi and identified a set of microRNAs as highly expressed nevus-enriched transcripts. Two of these microRNAs-MIR211-5p and MIR328-3p-induced mitotic failure, genome duplication, and proliferation arrest in human melanocytes through convergent targeting of AURKB. We demonstrate that <i>BRAF<sup>V600E</sup></i> induces a similar proliferation arrest in primary human melanocytes that is both reversible and conditional. Specifically, <i>BRAF<sup>V600E</sup></i> expression stimulates either arrest or proliferation depending on the differentiation state of the melanocyte. We report genome duplication in human melanocytic nevi, reciprocal expression of AURKB and microRNAs in nevi and melanomas, and rescue of arrested human nevus cells with AURKB expression. Taken together, our data describe an alternative molecular mechanism for melanocytic nevus formation that is congruent with both experimental and clinical observations.
Project description:The Aurora kinases form a family of 3 genes encoding serine/threonine kinases and are involved in the regulation of cell division during the mitosis. This study was designed to investigate the prognostic role of Aurora kinases in hepatocellular carcinoma (HCC). In this study, we analyzed the expression, overall survival (OS) data, promoter methylation level, and relationship with immunoinhibitors of Aurora kinases in patients with HCC from GEPIA2, UALCAN, OncoLnc, and TISIDB databases. Protein-protein interaction (PPI) network, gene ontology, Kyoto Encyclopedia of Genes and Genomes (KEGG), and Reactome pathway analysis were performed using the STRING database and Cytoscape software. We found that the mRNA expression, stages of HCC, and OS of AURKA and AURKB in HCC tissues were significantly different from control tissues, but there were significant inconsistencies in promoter methylation level and relationship with immunoinhibitors for AURKA and AURKB. None of the above items were significantly different for AURKC. Furthermore, a hub module including AURKA, AURKB, and AURKC was identified within the PPI network constructed with the Molecular Complex Detection (MCODE) plug-in in Cytoscape software. Our results show that AURKB could be a potential biomarker for HCC prognosis.
Project description:Rationale: Melanoma is an aggressive tumor of the skin and drug resistance is still a major problem in melanoma therapy. Novel targets and effective agents to overcome drug resistant melanoma are urgently needed in clinical therapy. Methods: Gene Expression Omnibus (GEO) database analysis, pathway enrichment analysis, and survival rate analysis were utilized to identify a candidate target. An anchorage-independent cell growth assay, flow cytometry, Western blot, and a xenograft mouse model were used to study the function of Aurora kinase B (AURKB) in both drug-sensitive and drug-resistant melanoma. Next, HI-511, a novel dual-target inhibitor targeting both AURKB and BRAF V600E, was designed and examined by an in vitro kinase assay. Methods as indicated above in addition to a BRAF V600E/PTEN-loss melanoma mouse model were used to demonstrate the effect of HI-511 on melanoma development in vitro and in vivo. Results: AURKB is highly expressed in melanoma and especially in vemurafenib-resistant melanoma and the expression was correlated with patient survival rate. Knocking down AURKB inhibited cell growth and induced apoptosis in melanoma, which was associated with the BRAF/MEK/ERKs and PI3-K/AKT signaling pathways. Importantly, we found that HI-511, a novel dual-target inhibitor against AURKB and BRAF V600E, suppresses both vemurafenib-sensitive and vemurafenib-resistant melanoma growth in vitro and in vivo by inducing apoptosis and mediating the inhibition of the BRAF/MEK/ERKs and PI3K/AKT signaling pathways. Conclusion: AURKB is a potential target for melanoma treatment. HI-511, a novel dual-target inhibitor against both AURKB and BRAF V600E, could achieve durable suppression of melanoma growth, even drug-resistant melanoma growth.
Project description:Despite significant advances, skin cutaneous melanoma (SKCM) is a common life-threatening cancer worldwide. Recently, pseudogenes have been discovered to be functional in many physiological processes and the pathogenesis of various diseases, including cancer. However, their relevance to SKCM remains largely unknown. In this study, seven upregulated pseudogenes were identified based on TCGA data. Among them, MTND4P12 was negatively correlated with the overall survival of SKCM patients. After constructing a pseudogene-miRNA-mRNA regulatory network, MTND4P12 was found to regulate the expression of oncogene AURKB by serving as a ceRNA. Both genetic and chemical inhibition of AURKB reduced viability and induced apoptosis of melanoma cells. Interestingly, DNA repair pathway seems to be involved in the anti-tumor effect of AURKB inhibition. Indeed, a synergistic therapeutic effect of AURKB inhibition and PARP inhibitor was confirmed both in vitro and in vivo. In conclusion, AURKB plays an oncogenic role and is a novel therapeutic target in SKCM. The combination of AURKB inhibition and PARP inhibitor has a synergistic effect, representing a promising treatment for SKCM.
Project description:Non-small cell lung cancer (NSCLC) tumors harboring mutations in EGFR ultimately relapse to therapy with EGFR tyrosine kinase inhibitors (EGFR TKIs). Here, we show that resistant cells without the p.T790M or other acquired mutations are sensitive to the Aurora B (AURKB) inhibitors barasertib and S49076. Phospho-histone H3 (pH3), a major product of AURKB, is increased in most resistant cells and treatment with AURKB inhibitors reduces the levels of pH3, triggering G1/S arrest and polyploidy. Senescence is subsequently induced in cells with acquired mutations while, in their absence, polyploidy is followed by cell death. Finally, in NSCLC patients, pH3 levels are increased after progression on EGFR TKIs and high pH3 baseline correlates with shorter survival. Our results reveal that AURKB activation is associated with acquired resistance to EGFR TKIs, and that AURKB constitutes a potential target in NSCLC progressing to anti-EGFR therapy and not carrying resistance mutations.