High Expression of Karyopherin-α2 Defines Poor Prognosis in Non–Muscle-Invasive Bladder Cancer and in Patients with Invasive Bladder Cancer Undergoing Radical Cystectomy

Chien

Molecular & Cellular Proteomics

et al. 2012

The process of nucleocytoplasmic shuttling is mediated by karyopherins. Dysregulated expression of karyopherins may trigger oncogenesis through aberrant distribution of cargo proteins. Karyopherin subunit alpha-2 (KPNA2) was previously identified as a potential biomarker for nonsmall cell lung cancer by integration of the cancer cell secretome and tissue transcriptome data sets. Knockdown of KPNA2 suppressed the proliferation and migration abilities of lung cancer cells. However, the precise molecular mechanisms underlying KPNA2 activity in cancer remain to be established. In the current study, we applied gene knockdown, subcellular fractionation, and stable isotope labeling by amino acids in cell culturebased quantitative proteomic strategies to systematically analyze the KPNA2-regulating protein profiles in an adenocarcinoma cell line. Interaction network analysis revealed that several KPNA2-regulating proteins are involved in the cell cycle, DNA metabolic process, cellular component movements and cell migration. Importantly, E2F1 was identified as a potential novel cargo of KPNA2 in the nuclear proteome. The mRNA levels of potential effectors of E2F1 measured using quantitative PCR indicated that E2F1 is one of the "master molecule" responses to KPNA2 knockdown. Immunofluorescence staining and immunoprecipitation assays disclosed colocalization and association between E2F1 and KPNA2. An in vitro protein binding assay further demonstrated that E2F1 interacts directly with KPNA2. Moreover, knockdown of KPNA2 led to subcellular redistribution of E2F1 in lung cancer cells. Our results collectively demonstrate the utility of quantitative proteomic approaches and provide a fundamental platform to further explore the biological roles of KPNA2 in nonsmall cell lung cancer. Molecular & Cellular

Section: E2f1 Is a Novel Cargo Of Kpna2mentioning

confidence: 52%

Quantitative Proteomics Reveals Regulation of Karyopherin Subunit Alpha-2 (KPNA2) and Its Potential Novel Cargo Proteins in Nonsmall Cell Lung Cancer

Chien

Molecular & Cellular Proteomics

et al. 2012

“…All tumors were reevaluated regarding T-stage and grade by the same uro-pathologist prior to placement on the TMA. The patients included and the TMA construction is described earlier [11]. …”

Section: Methodsmentioning

confidence: 99%

High expression of GEM and EDNRA is associated with metastasis and poor outcome in patients with advanced bladder cancer

et al. 2014

Self Cite

BackgroundThe standard treatment for non-metastatic muscle-invasive bladder cancer (stages T2–T4a) is radical cystectomy with lymphadenectomy. However, patients undergoing cystectomy show metastatic spread in 25% of cases and these patients will have limited benefit from surgery. Identification of patients with high risk of lymph node metastasis will help select patients that may benefit from neoadjuvant and/or adjuvant chemotherapy.MethodsRNA was procured by laser micro dissection of primary bladder tumors and corresponding lymph node metastases for Affymetrix U133 Plus 2.0 Gene Chip expression profiling. A publically available dataset was used for identification of the best candidate markers, and these were validated using immunohistochemistry in an independent patient cohort of 368 patients.ResultsGene Set Enrichment Analysis showed significant enrichment for e.g. metastatic signatures in the metastasizing tumors, and a set of 12 genes significantly associated with lymph node metastasis was identified. Tumors did not cluster according to their metastatic ability when analyzing gene expression profiles using hierarchical cluster analysis. However, half (6/12) of the primary tumor clustered together with matching lymph node metastases, indicating a large degree of intra-patient similarity in these patients. Immunohistochemical analysis of 368 tumors from cystectomized patients showed high expression of GEM (P = 0.033; HR = 1.46) and EDNRA (P = 0.046; HR = 1.60) was significantly associated with decreased cancer-specific survival.ConclusionsGEM and EDNRA were identified as promising prognostic markers for patients with advanced bladder cancer. The clinical relevance of GEM and EDNRA should be evaluated in independent prospective studies.

“…Cohorts A (162 patients) and B (273) were operated at the Department of Urology, Aarhus University Hospital, Denmark between 1980 and 2003 (A), and between 1992 and 2008 (B). Cohort B was defi ned for a previous research project [ 11 ] and consisted of all consecutive patients with accessible cystectomy tissue from this period. No patients from cohort A were included in cohort B.…”

Section: Methodsmentioning

confidence: 99%

Expression of TIP60 (tat‐interactive protein) and MRE11 (meiotic recombination 11 homolog) predict treatment‐specific outcome of localised invasive bladder cancer

Laurberg¹,

Brems-Eskildsen²,

Nordentoft³

et al. 2012

BJU International

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What's known on the subject? and What does the study add?Several studies have shown that defects in DNA‐damage response are associated with good survival after chemotherapy and radiotherapy. Furthermore, loss of cell cycle regulators may be prognostic indicators of poor survival after cystectomy. However, the potential clinical impact of previous findings is hampered by insufficient validation of significant results in suitable cystectomy and radiotherapy cohorts.Here we use a large cohort of patients receiving radiotherapy to successfully validate the importance of MRE11 as a predictive marker of disease‐specific survival (DSS). Furthermore, using two independent patient cohorts we show for the first time that TIP60 is a predictive marker of DSS after cystectomy. We show that combined use of TIP60 and MRE11 may hold the potential to guide treatment decisions.OBJECTIVE To determine the association between the proteins: tat‐interactive protein 60 kDa (TIP60), p16, meiotic recombination 11 homolog (MRE11), phosphorylated ataxia telangiectasia mutated (ATM), retinoblastoma protein (Rb), Ki67, and p53 and clinical outcome in invasive lymph node‐negative bladder cancer. PATIENTS AND METHODS Protein expression was measured by immunohistochemistry in cancer specimens from two independent cohorts of patients with bladder cancer treated with cystectomy (162 patients and 273) and one cohort of patients receiving radiotherapy (148). Disease‐specific survival (DSS) was used as the outcome measure, and patients with no disease‐specific death were followed for a minimum of 36 months. RESULTS TIP60 was significantly correlated with DSS in both cystectomy cohorts (hazard ratio [HR] 0.42, 95% confidence interval [CI] 0.26–0.68, P < 0.001 and HR 0.45, 95% CI 0.28–0.72, P= 0.001). MRE11 was significantly correlated with DSS in the cohort receiving radiotherapy (HR 0.64, 95% CI 0.47–0.86, P= 0.005). P16 was significantly correlated with DSS in all three cohorts (HR 0.46, 95% CI 0.30–0.75, P= 0.032; HR 0.60, 95% CI 0.37–0.97, P= 0.032; HR 0.52, 95% CI 0.28–0.96, P= 0.001). Rb was significantly correlated with DSS in one cystectomy cohort (HR 1.71, 95% CI 1.13–2.75, P= 0.017). Ki67, p53, and pATM were not significantly correlated with DSS in any of the cohorts. CONCLUSIONS TIP60 protein expression was a predictive marker for DSS after cystectomy in two independent cohorts. This novel marker was the strongest predictive factor in multivariate analysis in patients receiving cystectomy. MRE11 was shown to be a predictive marker for DSS after radiotherapy. We have shown that TIP60 and MRE11 hold the potential to guide patients with invasive bladder cancer to either cystectomy or radiotherapy. This study was based on retrospective material and consequently we suggest that these markers should be validated in a prospective study.