Prognostic significance of Aurora-A expression in human bladder cancer

Knowledge mapping of AURKA in Oncology：An advanced Bibliometric analysis (1998-2023)

AURKA, also known as Aurora kinase A, is a key molecule involved in the occurrence and progression of cancer. It plays crucial roles in various cellular processes, including cell cycle regulation, mitosis, and chromosome segregation. Dysregulation of AURKA has been implicated in tumorigenesis, promoting cell proliferation, genomic instability, and resistance to apoptosis. In this study, we conducted an extensive bibliometric analysis of research focusing on Aurora-A in the context of cancer by utilizing the Web of Science literature database. Various sophisticated computational tools, such as VOSviewer, Citespace, Biblioshiny R, and Cytoscape, were employed for comprehensive literature analysis and big data mining from January 1998 to September 2023.The primary objectives of our study were multi-fold. Firstly, we aimed to explore the chronological development of AURKA research, uncovering the evolution of scientific understanding over time. Secondly, we investigated shifting trends in research topics, elucidating areas of increasing interest and emerging frontiers. Thirdly, we delved into intricate signaling pathways and protein interaction networks associated with AURKA, providing insights into its complex molecular mechanisms. To further enhance the value of our bibliometric analysis, we conducted a meta-analysis on the prognostic value of AURKA in terms of patient survival. The results were visually presented, offering a comprehensive overview and future perspectives on Aurora-A research in the field of oncology. This study not only contributes to the existing body of knowledge but also provides valuable guidance for researchers, clinicians, and pharmaceutical professionals. By harnessing the power of bibliometrics, our findings offer a deeper understanding of the role of AURKA in cancer and pave the way for innovative research directions and clinical applications.

Clinical outcomes associated with expression of aurora kinase and p53 family members in muscle‑invasive bladder cancer

Biomarkers are needed in muscle-invasive bladder cancer (MIBC). We previously reported that high tumor aurora kinase (AURK) A expression identifies patients with MIBC with poor prognosis. Aberrant p53 expression has also been associated with poor outcomes in MIBC, though to the best of our knowledge, co-expression rates of p53 and aurora kinases have not been previously described in MIBC. As aurora kinase and p53 family members may co-regulate each other, the present study investigated whether tumor p53 or p63 protein expression influenced the prognostic value of AURKA in a pilot study of 50 patients with MIBC treated with curative intent. Immunohistochemistry for AURKA, AURKB, p53 and p63 were performed on archival pre-treatment tumor specimens and correlated with clinical outcomes in patients with MIBC who received neoadjuvant chemotherapy (NAC) prior to cystectomy. Baseline p53 [hazard ratio (HR) 1.46; 95% confidence interval (CI)=0.55-3.9; P=0.448) and p63 (HR 2.02; 95% CI=0.51-8.1; P=0.313) protein expression did not predict for overall survival (OS). Low p53 protein expression did not correlate with high AURKA (φ=0.190) or AURKB (φ=0.075) expression. However, in tumors with low p53 expression (n=17), the presence of either high AURKA or AURKB expression levels predicted an increased risk for relapse (HR 27.1; 95% CI=2.7-270.1; P=0.005) and mortality (HR 14.9; 95% CI=2.3-95.6; P=0.004) compared to tumors with both low AURKA and AURKB levels. The relationship between p63 and AURKA/B expression levels was not tested due to the prevalence (80%) of high p63 expression in the present cohort. In tumors with low AURKA expression, p53 status did not predict for OS (HR 0.62; 95% CI 0.2-3.2; P=0.572). In multivariable analysis, only high baseline AURKA expression predicted for inferior OS (HR 4.9; 95% CI 1.7-14.1; P=0.003). To the best of our knowledge, the present study was the first to report co-expression of p53 and aurora kinase family members in MIBC, and although wild-type p53 may regulate the aurora kinases in preclinical models, the adverse prognostic value of tumor AURKA overexpression was independent from baseline tumor p53 protein expression in the present cohort. AURKA remains an important prognostic biomarker in patients with MIBC and warrants further evaluation in prospective studies to validate whether baseline AURKA can identify patients that are unlikely to benefit from standard of care with NAC.

Identification of candidate biomarkers correlated with poor prognosis of breast cancer based on bioinformatics analysis

Breast cancer (BC) is a malignancy with high incidence among women in the world. This study aims to screen key genes and potential prognostic biomarkers for BC using bioinformatics analysis. Total 58 normal tissues and 203 cancer tissues were collected from three Gene Expression Omnibus (GEO) gene expression profiles, and then the differential expressed genes (DEGs) were identified. Subsequently, the Gene Ontology (GO) function and Kyoto Encyclopedia of Genes and Genome (KEGG) pathway were analyzed to investigate the biological function of DEGs. Additionally, hub genes were screened by constructing a protein–protein interaction (PPI) network. Then, we explored the prognostic value and molecular mechanism of these hub genes using Kaplan–Meier (KM) curve and Gene Set Enrichment Analysis (GSEA). As a result, 42 up-regulated and 82 down-regulated DEGs were screened out from GEO datasets. The DEGs were mainly related to cell cycles and cell proliferation by GO and KEGG pathway analysis. Furthermore, 12 hub genes (FN1, AURKA, CCNB1, BUB1B, PRC1, TPX2, NUSAP1, TOP2A, KIF20A, KIF2C, RRM2, ASPM) with a high degree were identified initially, among which, 11 hub genes were significantly correlated with the prognosis of BC patients based on the Kaplan–Meier-plotter. GSEA reviewed that these hub genes correlated with KEGG_CELL_CYCLE and HALLMARK_P53_PATHWAY. In conclusion, this study identified 11 key genes as BC potential prognosis biomarkers on the basis of integrated bioinformatics analysis. This finding will improve our knowledge of the BC progress and mechanisms.

Future prospects for mitosis-targeted antitumor therapies

Dysregulation of cell cycle progression is a hallmark of cancer cells. In recent years, efforts have been devoted to the development of new therapies that target proteins involved in cell cycle regulation and mitosis. Novel targeted antimitotic drugs include inhibitors of aurora kinase family, polo-like kinase 1, Mps1, Eg5, CENP-5 and the APC/cyclosome complex. While certain new inhibitors reached the clinical trial stage, most were discontinued due to negative results. However, these therapies should not be readily dismissed. Based on recent advances concerning their mechanisms of action, new strategies could be devised to increase their efficacy and promote further clinical trials. Here we discuss three main lines of action to empower these therapeutic approaches: increasing cell death signals during mitotic arrest, targeting senescent cells and facilitating antitumor immune response through immunogenic cell death (ICD).

San Huang Decoction Targets Aurora Kinase A to Inhibit Tumor Angiogenesis in Breast Cancer

San Huang Decoction (SHD), a Chinese herb formula, has been popularly prescribed in the clinical treatment of patients suffering from breast cancer. The aim of this study was to explore the anti-angiogenic effects of SHD in breast cancer and explain the underlying mechanism. Transwell and Matrigel assays showed that SHD reduced human umbilical vein endothelial cell migration and tubule formation and ELISA and qRT-PCR assays demonstrated its mediation of vascular endothelial growth factor (VEGF) expression. siRNA silencing of aurora kinase A (AURKA) produced results similar to those obtained by inhibition of AURKA with SHD. In addition, a chorioallantoic membrane assay was carried out to directly examine the effect of SHD on breast cancer anti-angiogenesis and immunofluorescence and immunohistochemical staining analysis showed that SHD reduced the expression of CD31, AURKA, and VEGF in a xenograft model. Furthermore, SHD regulated extracellular signal-regulated kinase expression in breast cancer cells, which was examined by western blotting. In conclusion, our findings indicated that SHD treatment mimicked the decrease in tumor neovascularization in breast cancer cells after the siRNA-mediated knockdown of AURKA. Thus, SHD may inhibit tumor angiogenesis in breast cancer by targeting AURKA and downregulating the ERK signaling pathway.

High aurora kinase expression identifies patients with muscle-invasive bladder cancer who have poor survival after neoadjuvant chemotherapy

OBJECTIVES

Overexpression of aurora kinase A (AURKA) confers a poor prognosis in patients with urothelial carcinoma of the bladder. The prognostic value of high aurora kinase B (AURKB) expression in local bladder cancer is not well defined, and whether the prognostic value of either AURKA or AURKB is affected by the use of chemotherapy is unknown. We sought to characterize the impact of high AURKA and AURKB expression on clinical outcome in patients with muscle-invasive bladder cancer (MIBC) who received neoadjuvant chemotherapy (NAC).

MATERIALS AND METHODS

Immunohistochemistry for AURKA and AURKB was performed on pretreatment diagnostic transurethral resection of bladder tumor (TURBT) and matched cystectomy specimens in 50 subjects with MIBC who received NAC. Receiver operator characteristic curves (ROC) were calculated to assess the impact of AURKA and AURKB expression on pathologic response rate. Kaplan-Meier techniques and Cox proportional hazards models were used to assess the association with relapse-free survival (RFS) and overall survival (OS).

RESULTS

Twenty-two of 50 [44%] patients had residual muscle-invasive (ypT2-4) urothelial carcinoma after NAC. Neither baseline tumor expression of AURKA (ROC = 0.57, P = 0.46) nor AURKB (ROC = 0.56, P = 0.87) predicted for ypT2-4 status. However, baseline expression of AURKA above the 75th percentile for this cohort was associated with an inferior RFS, (HR = 3.88, P = 0.008) and OS, (HR = 6.10, P < 0.001). Similar trends for worse survival outcomes were also observed for high AURKB levels (RFS, [HR = 2.2, P = 0.13] and OS, (HR = 2.25, P = 0.09).

CONCLUSIONS

High baseline tumor AURKA and AURKB expression identified MIBC patients with inferior RFS and OS despite the use of NAC and may identify patients who should be prioritized for clinical trial enrollment rather than standard cisplatin-based chemotherapy.

Aurora-A modulates MMP-2 expression via AKT/NF-κB pathway in esophageal squamous cell carcinoma cells

Esophageal squamous cell carcinoma (ESCC) is one of the most common malignancies. It is necessary to identify new markers for predicting tumor progression and therapeutic molecular targets. It has been reported that overexpressions of Aurora-A and matrix metalloproteinases 2 (MMP-2) may promote the malignant development of tumor. However, the relationship between Aurora-A and MMP-2 expression in tumor patients has not been investigated. In addition, the underlying mechanisms that Aurora-A regulates MMP-2 expression are still not fully elucidated. In this study, we demonstrated that Aurora-A and MMP-2 were overexpressed in ESCC tissues compared with paired normal adjacent tissues (P < 0.0001). Overexpression of Aurora-A was associated with the lymph node metastasis of ESCC (P = 0.01). Significantly, Aurora-A protein expression was positively correlated with MMP-2 protein expression in ESCC tissues (r = 0.66, P < 0.0001) as well as in ESCC cell lines. The level of Aurora-A expression was also positively correlated with the invasion capability of ESCC cells. Furthermore, Aurora-A overexpression significantly increased ESCC cell invasion by the upregulation of MMP-2 expression. In addition, Aurora-A overexpression promoted nuclear factor-kappaB (NF-κB) activation, and Aurora-A-mediated MMP-2 upregulation was abrogated by NF-κB inhibitor. Further analysis showed that activation of NF-κB was severely attenuated by AKT inhibitor in cells overexpressing Aurora-A. Taken together, these data indicate that Aurora-A overexpression upregulates MMP-2 expression through activating AKT/NF-κB signaling pathway in ESCC cells. These findings reveal that Aurora-A may be used as an important indicator for the judgment of malignant behavior of ESCC, and may be an attractive target for cancer therapy.

Increased expression of ESCO1 is correlated with poor patient survival and its role in human bladder cancer

There is increasing evidence suggesting that establishment of sister chromatid cohesion N-acetyltransferase 1 (ESCO1) was involved in tumorigenesis. However, its role in bladder cancer remains unclear. In this study, we aimed to study the clinical correlation and biological significance of ESCO1 in bladder cancer. Our results showed that ESCO1 was significantly over-expressed in bladder cancer tissues compared with that in adjacent normal tissues. And, increased ESCO1 expression was significantly associated with higher grade (P < 0.001), higher tumor stage (P = 0.014), and multifocality (P = 0.042). Kaplan-Meier analysis and Cox proportional hazards model were performed to determine the prognostic significance of ESCO1, and the results showed that ESCO1 is a useful prognostic marker for bladder cancer patients. Moreover, we found that ESCO1 knockdown inhibited the growth, migration, and invasion of bladder cancer cells. In conclusion, our findings indicated that ESCO1 may play an important role in human bladder cancer, and ESCO1 might serve as a novel target and prognosis factor for human bladder cancer.

Role of Aurora-A in Ovarian Cancer: A Meta-Analysis

BACKGROUND

Recently, several studies have examined associations between Aurora-A expression and clinical outcome in patients with ovarian cancer, but yielded conflicting results with respect to survival. Therefore, the aim of this study was to evaluate the prognostic significance of Aurora-A in ovarian cancer by performing a meta-analysis.

METHODS

PubMed, Cochrane library, Web of Science, Embase, Medline and Chinese BioMed Database (CBM) databases were searched systematically and only articles in which Aurora-A expression was detected by immunohistochemical staining were included. Hazard ratios (HRs) with 95% confidence intervals (CIs) were extracted and pooled for overall survival (OS) and disease-free survival (DFS).

RESULTS

Our results show that the pooled HR for OS was 1.40 (95% CI 0.82-1.98, p < 0.01) by univariate analysis in 7 articles (1,028) and 0.32 (95% CI 0.04-0.615, p = 0.23) by multivariate analysis in 3 studies (155). The association between Aurora-A expression and DFS was also statistically significant in 5 studies (HR = 1.14, 95% CI 0.50-1.78, p < 0.01).

CONCLUSION

This present meta-analysis suggests that the Aurora-A expression may be associated with poor prognosis in patients with ovarian cancer. Furthermore, studies of larger scale and well-matched regimes are warranted to confirm the findings in the future.

Deregulated expression of Aurora kinases is not a prognostic biomarker in papillary thyroid cancer patients

A number of reports indicated that Aurora-A or Aurora-B overexpression represented a negative prognostic factor in several human malignancies. In thyroid cancer tissues a deregulated expression of Aurora kinases has been also demonstrated, but no information regarding its possible prognostic role in differentiated thyroid cancer is available. Here, we evaluated Aurora-A and Aurora-B mRNA expression and its prognostic relevance in a series of 87 papillary thyroid cancers (PTC), with a median follow-up of 63 months. The analysis of Aurora-A and Aurora-B mRNA levels in PTC tissues, compared to normal matched tissues, revealed that their expression was either up- or down-regulated in the majority of cancer tissues. In particular, Aurora-A and Aurora-B mRNA levels were altered, respectively, in 55 (63.2%) and 79 (90.8%) out of the 87 PTC analyzed.A significant positive correlation between Aurora-A and Aurora-B mRNAs was observed (p=0.001). The expression of both Aurora genes was not affected by the BRAFV600E mutation. Univariate, multivariate and Kaplan-Mayer analyses documented the lack of association between Aurora-A or Aurora-B expression and clinicopathological parameters such as gender, age, tumor size, histology, TNM stage, lymph node metastasis and BRAF status as well as disease recurrences or disease-free interval. Only Aurora-B mRNA was significantly higher in T(3-4) tissues, with respect to T(1-2) PTC tissues. The data reported here demonstrate that the expression of Aurora kinases is deregulated in the majority of PTC tissues, likely contributing to PTC progression. However, differently from other human solid cancers, detection of Aurora-A or Aurora-B mRNAs is not a prognostic biomarker in PTC patients.

Prognostic factors in urothelial carcinoma of the bladder: histologic and molecular correlates

Histologic characterization of urothelial carcinoma remains the most important factor for determining a patient's prognosis and treatment regimen. However, challenges remain in accurately staging and grading many tumors, and substaging remains controversial. Recently, significant insight has been gained into the molecular pathogenesis of bladder cancer that may aid in further characterizing urothelial carcinoma. Many molecular biomarkers have been clinically validated, and some have been shown to provide more prognostic information than histology alone. In addition, a subset of these markers may even represent targets for molecular therapy. Here, we review histologic staging and grading of urothelial carcinoma, as well as discuss many of the clinically relevant molecular markers. As each urothelial carcinoma likely represents a unique biological entity, the need for complete histologic and molecular characterization of these tumors is necessary as we enter the age of personalized medicine.

SATB1 overexpression regulates the development and progression in bladder cancer through EMT

The global gene regulator Special AT-rich sequence-binding protein-1 (SATB1) has been reported to induce EMT-like changes and be associated with poor clinical outcome in several cancers. This study aims to evaluate whether SATB1 affects the biological behaviors of bladder transitional cell carcinoma (BTCC) and further elucidate if this effect works through an epithelial-mesenchymal transition (EMT) pathway. The expression of SATB1, E-cadherin (epithelial markers), vimentin (mesenchymal markers) in BTCC tissues and adjacent noncancerous tissues, as well as in two cell lines of bladder cancer were investigated. Whether the SATB1 expression is associated with clinicopathological factors or not was statistically analyzed. Cell invasion and migration, cell cycle, cell proliferation and apoptosis were evaluated in SATB1 knockdown and overexpressed cell lines. Our results showed that the expression of SATB1 was remarkably up-regulated both in BTCC tissues and in bladder cancer cell lines with high potential of metastasis. The results were also associated with EMT markers and poor prognosis of BTCC patients. Moreover, SATB1 induced EMT processes through downregulation of E-cadherin, upregulation of E-cadherin repressors (Snail, Slug and vimentin). SATB1 also promoted cell cycle progression, cell proliferation, cell invasion and cell migration, but did not alter cell survival. In conclusion, our results suggest that SATB1 plays a crucial role in the progression of bladder cancer by regulating genes controlling EMT processes. Further, it may be a novel therapeutic target for aggressive bladder cancers.

Identification of pVHL as a novel substrate for Aurora-A in clear cell renal cell carcinoma (ccRCC)

Clear cell renal cell carcinoma (ccRCC) is the most common histological subtype of kidney cancer and is often characterized by mutations or deletions of the Von Hippel Lindau (VHL) tumour suppressor gene. Aurora gene family members are implicated in proper mitotic progression and spindle checkpoint function and play a crucial role in cancer progression. In the present study, we assessed the expression of Aurora-A in a cohort of 30 ccRCC with fully characterized VHL status (wt/wt or mut/del) and Fuhrman grade. Aurora-A transcript and protein levels were significantly increased in high Fuhrman grade tumours and in VHLwt/wt tumours. These results suggest that Aurora-A and VHL interact in the ccRCC. We demonstrated that the two proteins interact in vivo and identified the Ser72 on the sequence of VHL as the unique site phosphorylated by Aurora-A.

Republished: non-invasive urine based tests for the detection of bladder cancer

Bladder cancer is the fourth most frequently diagnosed malignant neoplasm and cause of cancer-related deaths in men and eighth in women. Patients with bladder cancer undergo repeated cystoscopic examinations of the bladder to monitor for tumour recurrence which is invasive, costly and lacks accuracy. Therefore, the development of non-invasive urine based tests for the early detection of bladder cancer would be of tremendous benefit to both patients and healthcare systems. A number of urine based markers are available for the early diagnosis of bladder cancer. The diagnosis of bladder cancer relies on identifying malignant cells in the urine. All urinary markers have a higher sensitivity as compared with cytology but they score lower in specificity. Many soluble and cell based markers have been developed. Only two of the soluble and cell based markers have obtained the Food and Drug Administration approval. In the current review, the most recent literature of urinary markers is summarised. This article reports some of the more prominent urine markers and new technologies used nowadays.

The investigational Aurora kinase A inhibitor MLN8237 induces defects in cell viability and cell-cycle progression in malignant bladder cancer cells in vitro and in vivo

PURPOSE

Despite more than 70,000 new cases of bladder cancer in the United States annually, patients with advanced disease have a poor prognosis due to limited treatment modalities. We evaluated Aurora kinase A, identified as an upregulated candidate molecule in bladder cancer, as a potential therapeutic target.

EXPERIMENTAL DESIGN

Gene expression in human bladder cancer samples was evaluated using RNA microarray and quantitative reverse transcriptase PCR. Effects of the Aurora kinase A inhibitor MLN8237 (Millennium) on cell dynamics in malignant T24 and UM-UC-3 and papilloma-derived RT4 bladder cells were evaluated in vitro and in vivo in a mouse xenograft model.

RESULTS

A set of 13 genes involved in the mitotic spindle checkpoint, including Aurora kinases A and B, were upregulated in human urothelial carcinoma compared with normal urothelium. The Aurora kinase A inhibitor MLN8237 induced cell-cycle arrest, aneuploidy, mitotic spindle failure, and apoptosis in the human bladder cancer cell lines T24 and UM-UC-3. MLN8237 also arrested tumor growth when administered orally over 4 weeks in a mouse bladder cancer xenograft model. Finally, in vitro sequential administration of MLN8237 with either paclitaxel or gemcitabine resulted in synergistic cytotoxic effects in T24 cells.

CONCLUSIONS

Mitotic spindle checkpoint dysfunction is a common characteristic of human urothelial carcinoma and can be exploited with pharmacologic Aurora A inhibition. Given our demonstration of the ability of the Aurora A inhibitor MLN8237 to inhibit growth of bladder cancer in vitro and in vivo, we conclude that Aurora kinase inhibitors warrant further therapeutic investigation in bladder cancer.

Low concentration of arsenic-induced aberrant mitosis in keratinocytes through E2F1 transcriptionally regulated Aurora-A

Chronic exposure to low-concentration arsenic promotes cell proliferation and carcinogenesis both in vitro and in vivo. Centrosome amplification, the major cause of chromosome instability, occurs frequently in cancers. Aurora-A is a mitotic kinase and causes centrosome amplification and chromosome instability when overexpressed. Our previous study revealed that low-concentration arsenic induces Aurora-A overexpression in immortalized bladder cells. In this study, we hypothesized that low-concentration arsenic induces aberrant mitosis in keratinocytes due to Aurora-A overexpression. The specimen of Bowen's disease (BD) and squamous cell carcinoma obtained from arseniasis-endemic areas in Taiwan showed Aurora-A overexpression. The mRNA/protein levels and kinase activity of Aurora-A were increased in immortalized keratinocyte HaCaT cells after arsenic treatment at low concentration (< 1µM). Aberrant spindles, multiple centrosomes, and multinucleated cells were detected under fluorescent microscopy in HaCaT cells after arsenic treatment. These findings were associated with increased expression of Aurora-A. We further revealed that Aurora-A was regulated by arsenic-induced transcriptional factor E2F1 as demonstrated by chromosome immunoprecipitation, promoter activity, and small interfering RNA assays. Finally, in arsenic-treated HaCaT cells and in BD, a significant increase of dysfunctional p53 was found, and this event correlated with the increase in expression of Aurora-A. Altogether, our data suggest that low concentration of arsenic induces activation of E2F1-Aurora-A axis and results in aberrant mitosis of keratinocytes. Overexpression of Aurora-A and dysfunctional p53 may act synergistically to trigger skin tumor formation. Our findings suggest that Aurora-A may be a potential target for the prevention and treatment of arsenic-related cancers.

Non-invasive urine based tests for the detection of bladder cancer

Bladder cancer is the fourth most frequently diagnosed malignant neoplasm and cause of cancer-related deaths in men and eighth in women. Patients with bladder cancer undergo repeated cystoscopic examinations of the bladder to monitor for tumour recurrence which is invasive, costly and lacks accuracy. Therefore, the development of non-invasive urine based tests for the early detection of bladder cancer would be of tremendous benefit to both patients and healthcare systems. A number of urine based markers are available for the early diagnosis of bladder cancer. The diagnosis of bladder cancer relies on identifying malignant cells in the urine. All urinary markers have a higher sensitivity as compared with cytology but they score lower in specificity. Many soluble and cell based markers have been developed. Only two of the soluble and cell based markers have obtained the Food and Drug Administration approval. In the current review, the most recent literature of urinary markers is summarised. This article reports some of the more prominent urine markers and new technologies used nowadays.

The ubiquitin-specific protease USP2a enhances tumor progression by targeting cyclin A1 in bladder cancer

The deubiquitinating enzyme USP2a has shown oncogenic properties in many cancer types by impairing ubiquitination of FASN, MDM2, MDMX or Aurora A. Aberrant expression of USP2a has been linked to progression of human tumors, particularly prostate cancer. However, little is known about the role of USP2a or its mechanism of action in bladder cancer. Here, we provide evidence that USP2a is an oncoprotein in bladder cancer cells. Enforced expression of USP2a caused enhanced proliferation, invasion, migration and resistance to several chemotherapeutic reagents, while USP2a loss resulted in slower proliferation, greater chemosensitivity and reduced migratory/invasive capability compared with control cells. USP2a, but not a catalytically inactive mutant, enhanced proliferation in immortalized TRT-HU1 normal human bladder epithelial cells. USP2a bound to cyclin A1 and prevented cyclin A1 ubiquitination, leading to accumulation of cyclin A1 by a block in degradation. Enforced expression of wild type USP2a, but not an inactive USP2a mutant, resulted in cyclin A1 accumulation and increased cell proliferation. We conclude that USP2a impairs ubiquitination and stabilizes an important cell cycle regulator, cyclin A1, raising the possibility of USP2a targeting as a therapeutic strategy against bladder tumors in combination with chemotherapy.

Expression of hedgehog pathway components is associated with bladder cancer progression and clinical outcome

Hedgehog (Hh) pathway has been implicated in the tumorigenesis of a large number of human tumors. But its effects on the progression and prognosis of bladder cancer remain poorly understood. The aim of this study was to investigate expression patterns of Hh pathway components in bladder cancer and to elucidate their prognostic values in this tumor. The expression of sonic hedgehog (Shh), its receptor Patched (Ptch1), and downstream transcription factor Gli1 in 118 specimens of bladder cancer and 30 specimens of adjacent normal bladder tissue was determined by immunohistochemistry. Statistical analyses were applied to test the relationship between the expression of these three proteins and clinicopathologic features and prognosis. Immunohistochemical staining results showed the localizations of Shh and Ptch1 proteins to be mainly located in the cytoplasm of bladder cancer cells, whereas Gli1 was mainly localized in the nuclear of tumor cells. Additionally, positive expression of Shh, Ptch1 and Gli1 proteins was correlated with pathological stage (P = 0.006, 0.006 and 0.008, respectively), venous invasion (P = 0.01, 0.01 and 0.012, respectively) and lymph node metastasis (P = 0.009, 0.01 and 0.013, respectively), but not with other factors including age, gender, tumor grade and recurrence of superficial cancer. Moreover, patients with positive expression of Shh, Ptch1 and Gli1 proteins respectively showed poorer disease-free (P = 0.002, 0.002 and 0.001, respectively) and overall survival (all P < 0.001) than those with negative expression of these three proteins. Univariate and multivariate analysis of prognostic factors in bladder cancer patients indicated that the expression patterns of Shh, Ptch1 and Gli1 proteins were independent unfavorable prognostic factors (all P < 0.001). This is the first report describing about the correlation between Hh pathway and the prognosis of bladder cancer. Expression of Shh, Ptch1 and Gli1 proteins was greater in bladder cancers than in the adjacent normal tissues. The examination of their expression is potentially valuable in prognostic evaluation of bladder cancer.