Eun-Jung Kim

Predictive value of progression-related gene classifier in primary non-muscle invasive bladder cancer

BackgroundWhile several molecular markers of bladder cancer prognosis have been identified, the limited value of current prognostic markers has created the need for new molecular indicators of bladder cancer outcomes. The aim of this study was to identify genetic signatures associated with disease prognosis in bladder cancer.ResultsWe used 272 primary bladder cancer specimens for microarray analysis and real-time reverse transcriptase polymerase chain reaction (RT-PCR) analysis. Microarray gene expression analysis of randomly selected 165 primary bladder cancer specimens as an original cohort was carried out. Risk scores were applied to stratify prognosis-related gene classifiers. Prognosis-related gene classifiers were individually analyzed with tumor invasiveness (non-muscle invasive bladder cancer [NMIBC] and muscle invasive bladder cancer [MIBC]) and prognosis. We validated selected gene classifiers using RT-PCR in the original (165) and independent (107) cohorts. Ninety-seven genes related to disease progression among NMIBC patients were identified by microarray data analysis. Eight genes, a progression-related gene classifier in NMIBC, were selected for RT-PCR. The progression-related gene classifier in patients with NMIBC was closely correlated with progression in both original and independent cohorts. Furthermore, no patient with NMIBC in the good-prognosis signature group experienced cancer progression.ConclusionsWe identified progression-related gene classifier that has strong predictive value for determining disease outcome in NMIBC. This gene classifier could assist in selecting NMIBC patients who might benefit from more aggressive therapeutic intervention or surveillance.

Methylation of the RUNX3 promoter as a potential prognostic marker for bladder tumor.

PURPOSEnDNA methylation is a key regulator of gene transcription and genomic stability, and alterations in DNA methylation patterns are frequently detected in human tumors. Previously we reported that inactivation of RUNX3 by primarily epigenetic alterations in DNA methylation is closely associated with bladder tumor development, recurrence and progression. In the current series we evaluated the association between RUNX3 inactivation and bladder tumors after a long-term followup study.nnnMATERIALS AND METHODSnWe used previously published data on the methylation patterns of RUNX3 in bladder tumor samples as well as 25 new data sets obtained by methylation specific polymerase chain reaction and direct DNA sequencing. Of the 149 patients examined 118 were followed periodically and included in the final analysis. Median followup was 49.8 months (range 1 to 146).nnnRESULTSnRUNX3 promoter methylation was observed in 84 of the 118 tumor samples (71.2%) examined. RUNX3 methylation patterns correlated significantly with the development of invasive tumor, tumor progression, and overall and cancer specific survival (each p <0.05). Kaplan-Meyer curves showed identical results (p <0.05). Multivariate Cox regression models revealed that RUNX3 methylation status was a strong predictor of tumor progression and cancer specific survival.nnnCONCLUSIONSnResults strongly suggest that inactivation of RUNX3 by the methylation of its promoter region is a significant risk factor for invasive bladder tumors, tumor progression and cancer specific survival. RUNX3 promoter methylation status could be a promising marker for assessing the prognosis of human bladder tumors.

Magnolol elicits activation of the extracellular signal-regulated kinase pathway by inducing p27KIP1-mediated G2/M-phase cell cycle arrest in human urinary bladder cancer 5637 cells

Magnolol has been reported to play a role in antitumor activity. However, the relevant pathway integrating cell cycle regulation and signaling pathways involved in growth inhibition in cancer cells remains to be identified. In the present study, magnolol treatment of these cells resulted in significant dose-dependent growth inhibition together with apoptosis, G1- and G2/M-phase cell cycle arrest at a 60 microM (IC50) dose in 5637 bladder cancer cells. In addition, magnolol treatment strongly induced p27KIP1 expression, and down-regulated expression of cyclin-dependent kinases (CDKs) and cyclins. Moreover, treatment with magnolol-induced phosphorylation of ERK, p38 MAP kinase, and JNK. Among the pathway inhibitors examined, only PD98059, an ERK-specific inhibitor, blocked magnolol-dependent p27KIP1 expression. Blockade of ERK function consistently reversed magnolol-mediated inhibition of cell proliferation and decreased G2/M cell cycle proteins, but not G1 cell cycle proteins. Furthermore, magnolol treatment increased both Ras and Raf activation. Transfection of cells with dominant negative Ras (RasN17) and Raf (RafS621A) mutant genes suppressed magnolol-induced ERK activity and p27KIP1 expression. Finally, the magnolol-induced reduction in cell proliferation and G2/M cell cycle proteins was also abolished in the presence of RasN17 and RafS621A mutant genes. These data demonstrate that the Ras/Raf/ERK pathway participates in p27KIP1 induction, leading to a decrease in the levels of cyclin B1/Cdc2 complexes and magnolol-dependent inhibition of cell growth. Overall, these novel findings concerning the molecular mechanisms of magnolol in 5637 bladder cancer cells provide a theoretical basis for therapeutic treatment of malignancies.

Clinical implications and prognostic values of topoisomerase-II alpha expression in primary non-muscle-invasive bladder cancer.

OBJECTIVESnTo investigate the association between expression levels of topoisomerase-II alpha (TOP-2alpha) and prognosis in primary non-muscle-invasive bladder cancer (NMIBC). TOP-2alpha, a marker of cell proliferation, has been assessed as a prognostic indicator in several types of cancer. However, currently available data on the role of TOP-2alpha in prognosis are inconsistent.nnnMETHODSnTop-2alpha messenger ribonucleic acid (mRNA) levels were examined in 103 tumor specimens from patients with primary NMIBC by real-time polymerase chain reaction. Immunohistochemical staining was performed on 39 matched tumor samples. The median follow-up period for all patients was 51.8 months (range, 3.2-137).nnnRESULTSnThe mRNA expression levels of TOP-2alpha were significantly elevated in subjects with high-grade (P<.001) and high-stage (P=.041) tumors as compared with subjects with low-grade and low-stage tumors. Kaplan-Meier estimates revealed significant variation in tumor recurrence and progression depending on the level of TOP-2alpha expression (log-rank test, P<.05). Multivariate Cox regression analysis revealed that the level of TOP-2alpha expression is a strong predictor of recurrence (hazard ratio, 2.507; 95% confidence interval, 1.228-5.116; P=.012) and progression (hazard ratio, 4.192; 95% confidence interval, 1.002-17.536; P=.049) for NMIBC. The results of immunohistochemical staining generally correlated with mRNA expression levels.nnnCONCLUSIONSnEnhanced expression of TOP-2alpha is positively associated with a high rate of recurrence and progression in NMIBC. Thus, TOP-2alpha represents a promising marker of prognosis for NMIBC.

Inhibitory effects of the aqueous extract of Magnolia officinalis on the responses of human urinary bladder cancer 5637 cells in vitro and mouse urinary bladder tumors induced by N‐Butyl‐N‐(4‐hydroxybutyl) nitrosamine in vivo

This study investigated the anticancer activity of Magnolia officinalis on urinary bladder cancer in vitro and in vivo, and elucidated the mechanism of its activity. An aqueous extract of M. officinalis inhibited cell viability and DNA synthesis in cultured human urinary bladder cancer 5637 cells. Inhibition of proliferation was the result of apoptotic induction, because FACS analyses of 5637 cells treated with M. officinalis showed a sub‐G1 phase accumulation. M. officinalis extract also increased cytoplasmic DNA–histone complex dose‐dependently. These inhibitory effects were associated with the upregulation of proapoptotic molecules Bax, cytochrome c and caspase 3. Treatment of 5637 cells with M. officinalis extract suppressed the expression of matrix metalloproteinase 2 (MMP‐2) and MMP‐9, as revealed by zymographic and immunoblot analyses. When M. officinalis extract was given to mice simultaneously with the carcinogen N‐butyl‐N‐(4‐hydroxybutyl) nitrosamine, which induces urinary bladder tumors, the size of the induced tumors was smaller. Finally, histological data indicated that the histological grade of carcinoma and the depth of invasion were dramatically decreased by treatment with M. officinalis extract in mice with N‐butyl‐N‐(4‐hydroxybutyl) nitrosamine‐induced urinary bladder tumors. In conclusion, the findings showed that M. officinalis extract exhibited potential chemopreventive activity against urinary bladder tumor in vitro and in vivo. Copyright

Analysis of hOGG1 genotype as a prognostic marker for muscle invasive bladder cancer: a novel approach using peptide nucleic acid-mediated, real-time PCR clamping.

OBJECTIVEnDNA damage repair mechanisms are a source of genetic mutation and are believed to play an important role in human cancer. Human 8-oxoguanine DNA glycosylase 1 (hOGG1) is involved in the recognition and repair of DNA damage. The value of the hOGG1 genotype as a prognostic indicator for bladder cancer (BC) was assessed using a novel technological approach.nnnMATERIALS AND METHODSnThe association between genetic polymorphisms of hOGG1 codon 326 and clinicopathologic characteristics of 337 patients with BC was analyzed using peptide nucleic acid (PNA)-mediated real-time PCR clamping.nnnRESULTSnTumor grade and size were significantly associated with the hOGG1 codon 326 genotype in non-muscle-invasive bladder cancer (NMIBC). The Cys326Cys polymorphism was significantly associated with progression and cancer specific survival in patients with muscle-invasive bladder cancer (MIBC). Multivariate Cox regression analysis indicated that the hOGG1 Cys326Cys polymorphism is associated with a protective effect on progression and a more dominant survival benefit than the Ser326Ser polymorphism in MIBC (hazard ratio 0.284 and 0.305, respectively).nnnCONCLUSIONSnAnalysis of genotypes and clinical data for 337 BC patients indicates that the hOGG1 genotype may be a useful prognostic genetic marker for MIBC.

Identification of S100A8-correlated genes for prediction of disease progression in non-muscle invasive bladder cancer

BackgroundS100 calcium binding protein A8 (S100A8) has been implicated as a prognostic indicator in several types of cancer. However, previous studies are limited in their ability to predict the clinical behavior of the cancer. Here, we sought to identify a molecular signature based on S100A8 expression and to assess its usefulness as a prognostic indicator of disease progression in non-muscle invasive bladder cancer (NMIBC).MethodsWe used 103 primary NMIBC specimens for microarray gene expression profiling. The median follow-up period for all patients was 57.6 months (range: 3.2 to 137.0 months). Various statistical methods, including the leave-one-out cross validation method, were applied to identify a gene expression signature able to predict the likelihood of progression. The prognostic value of the gene expression signature was validated in an independent cohort (n = 302).ResultsKaplan-Meier estimates revealed significant differences in disease progression associated with the expression signature of S100A8-correlated genes (log-rank test, P < 0.001). Multivariate Cox regression analysis revealed that the expression signature of S100A8-correlated genes was a strong predictor of disease progression (hazard ratio = 15.225, 95% confidence interval = 1.746 to 133.52, P = 0.014). We validated our results in an independent cohort and confirmed that this signature produced consistent prediction patterns. Finally, gene network analyses of the signature revealed that S100A8, IL1B, and S100A9 could be important mediators of the progression of NMIBC.ConclusionsThe prognostic molecular signature defined by S100A8-correlated genes represents a promising diagnostic tool for the identification of NMIBC patients that have a high risk of progression to muscle invasive bladder cancer.

A Case of Streptococcus salivarius Meningitis in a Patient with Cerebrospinal Fluid Rhinorrhea after Skull Base Fracture

A Case of Streptococcus salivarius Meningitis in a Patient with Cerebrospinal Fluid Rhinorrhea after Skull Base Fracture Kyeong Seob Shin, Dong Ik Shin, Woo Sub Shim, Byeong Cheol Rim, Il Hun Bae, Seung Young Lee, Dong Hee Ryu, Eun Jung Kim, Bo Ra Son Departments of Laboratory Medicine, Neurology, Otorhinolaryngology-Head and Neck Surgery, Neurosurgery, Radiology and Surgery, Chungbuk National University College of Medicine, Department of Pathology, Chungbuk National University Hospital, Cheongju, Korea