mRNA Expression of S100A8 as a Prognostic Marker for Progression of Non-Muscle-Invasive Bladder Cancer

Prognostic Role of S100A8 in Human Solid Cancers: A Systematic Review and Validation

Background

S100A8 plays a key role in many cellular processes and is highly expressed in various solid cancers. However, the prognostic role of S100A8 has not been well defined. Therefore, we conducted a quantitative meta-analysis to investigate whether or not S100A8 could be used as a prognostic biomarker in solid tumors.

Methods

PubMed, Web of Science, Embase, and Cochrane library were searched to acquire relevant studies that evaluated the association between expression of S100A8 and prognosis of cancer patients. Pooled hazard ratios (HRs) with their corresponding 95% confidence intervals (CIs) were extracted to evaluate the association between S100A8 overexpression and Overall Survival (OS), Disease-Free Survival (DFS), Recurrence-Free Survival (RFS), and Progression-Free Survival (PFS). The expression of S100A8 was also validated by Flow cytometry, immunohistochemistry (IHC), and western blot.

Results

A total of 2,817 patients from 13 independent studies, ranging from 43 to 1,117 patients in size, were statistically analyzed. Our results indicated that a high level of S100A8 expression was significantly associated with poor OS, poor DFS, and poor PFS/RFS. In term of clinical pathological characteristics, a high expression level of S100A8 was significantly associated with differentiation grades, lymphatic metastasis, ER statue, and PR statue. The validation studies showed that the expression of S100A8 was at high levels in MDA-MB-231 (79.7%), MDA-MB-453 (89.2%), HTB-9 (70.2%), and T24 (53.3%) cells and it was higher in breast cancer tissue and bladder cancer tissue than their corresponding para-carcinoma tissue.

Conclusions

S100A8 overexpression was significantly associated with poor clinical prognosis in cancer patients. S100A8 is potential a prognostic biomarker in breast cancer and bladder cancer. More well-designed studies with adequate prognostic data are needed to confirm the prognostic role of S100A8 revealed in this study.

Friend or Foe: S100 Proteins in Cancer

S100 proteins are widely expressed small molecular EF-hand calcium-binding proteins of vertebrates, which are involved in numerous cellular processes, such as Ca²⁺ homeostasis, proliferation, apoptosis, differentiation, and inflammation. Although the complex network of S100 signalling is by far not fully deciphered, several S100 family members could be linked to a variety of diseases, such as inflammatory disorders, neurological diseases, and also cancer. The research of the past decades revealed that S100 proteins play a crucial role in the development and progression of many cancer types, such as breast cancer, lung cancer, and melanoma. Hence, S100 family members have also been shown to be promising diagnostic markers and possible novel targets for therapy. However, the current knowledge of S100 proteins is limited and more attention to this unique group of proteins is needed. Therefore, this review article summarises S100 proteins and their relation in different cancer types, while also providing an overview of novel therapeutic strategies for targeting S100 proteins for cancer treatment.

Decrease in skeletal muscle index 1 year after radical cystectomy as a prognostic indicator in patients with urothelial bladder cancer

PURPOSE

The present study aimed to determine whether sarcopenia after radical cystectomy (RC) could predict overall survival (OS) in patients with urothelial bladder cancer (UBC).

MATERIALS AND METHODS

The lumbar skeletal muscle index (SMI) of 80 patients was measured before and 1 year after RC. The prognostic signifi cance of sarcopenia and SMI decrease after RC were evaluated using Kaplan-Meier analysis and a multivariable Cox regression model.

RESULTS

Of 80 patients, 26 (32.5%) experienced sarcopenia before RC, whereas 40 (50.0%) experienced sarcopenia after RC. The median SMI change was -2.2 cm2/m2. Patients with sarcopenia after RC had a higher pathological T stage and tumor grade than patients without sarcopenia. Furthermore, the overall mortality rate was signifi - cantly higher in patients with sarcopenia than in those without sarcopenia 1 year after RC. The median follow-up time was 46.2 months, during which 22 patients died. Kaplan-Meier estimates showed a signifi cant difference in OS rates based on sarcopenia (P=0.012) and SMI decrease (P=0.025). Multivariable Cox regression analysis showed that SMI decrease (≥2.2 cm2/m2) was an independent predictor of OS (hazard ratio: 2.68, confi dence interval: 1.007-7.719, P = 0.048).

CONCLUSIONS

The decrease in SMI after surgery might be a negative prognostic factor for OS in patients who underwent RC to treat UBC.

Calgranulin A (S100A8) Immunostaining: A Future Candidate for Risk Assessment in Patients with Non-Muscle-Invasive Bladder Cancer (NMIBC)

INTRODUCTION

There is an urgent need to identify patients with bladder cancer (BC) who are at high risk of recurrence or progression. Calgranulin A is a strong marker for muscle-invasive or advanced BC and recent studies have shown its potential for identifying patients at risk even in non-muscle-invasive bladder cancer (NMIBC). The present study examines risks of recurrence and progression dependent on immunostaining with calgranulin A in NMIBC.

METHODS

Calgranulin A protein expression was evaluated through the immunohistochemistry of 158 randomly selected, transurethrally resected BC specimens of separate patients (pTa 89, pT1 69) using tissue microarrays. Kaplan-Meier survival analysis and Cox regression were performed to determine whether calgranulin A expression is associated with recurrence-free survival (RFS), progression-free survival (PFS), or cancer-specific survival (CSS).

RESULTS

Calgranulin A expression is significantly different between pTa and pT1 tumors (p = 0.000, Mann-Whitney U test) and between tumor grades (p = 0.015, Kruskal-Wallis test). Kaplan-Meier estimates produced significant results for low and high calgranulin A expression concerning RFS [5y-RFS 70.4 ± 4.0% vs. 35.9 ± 12.5%, median RFS not reached (NR) vs. 12.0 ± 4.4 month, p = 0.029, log-rank test], PFS (5y-PFS 90.3 ± 2.7% vs. 51.5 ± 14.0%, median PFS NR in both groups, p = 0.000, log-rank test), and CSS (5y-CSS 92.9 ± 2.6% vs. 70.7 ± 12.4%, median CSS NR in both groups, p = 0.005, log-rank test). Calgranulin A remained an independent factor for RFS (p = 0.024, HR 2.43) and PFS (p = 0.002, HR 5.92) according to the multivariate Cox regression model.

CONCLUSIONS

Calgranulin A expression in NMIBC, detected through immunohistochemistry, is a promising marker for the identification of NMIBC patients at high risk of recurrence and progression.

Clinical and in vitro analysis of Osteopontin as a prognostic indicator and unveil its potential downstream targets in bladder cancer

Osteopontin (OPN) plays an important role in cancer progression, however its prognostic significance and its downstream factors are largely elusive. In this study, we have shown that expression of OPN was significantly higher in bladder cancer specimens with higher T-stage or tumor grades. In addition, a high level of OPN was significantly associated with poorer survival in two independent bladder cancer patient cohorts totaling 389 bladder cancer patients with available survival data. We further identified Matrix metallopeptidase 9 (MMP9) and S100 calcium-binding protein A8 (S100A8) were both downstream factors for OPN in bladder cancer specimens and bladder cancer cell lines. Expression of OPN was significantly positively associated with that of MMP9 and S100A8, while overexpression of OPN resulted in upregulation of MMP9 and S100A8, and knockdown of OPN showed consistent downregulation of MMP9 and S100A8 expression levels. Importantly, expression levels of both MMP9 and S100A8 were significantly associated with higher T-stage, higher tumor grade and a shorter survival time in the bladder cancer patients. Interestingly, OPN expression only predicted survival in MMP9-high, but not MMP9-low subgroups, and in S100A8-low but not S100A8-high subgroups. Our results suggest that OPN, MMP9 and S100A8 all play a significant role in bladder cancer progression and are potential prognostic markers and therapeutic targets in bladder cancer. The mechanistic link between these three genes and bladder cancer progression warrants further investigation.

Diagnostic performance of the urinary canine calgranulins in dogs with lower urinary or urogenital tract carcinoma

BACKGROUND

Onset of canine transitional cell carcinoma (TCC) and prostatic carcinoma (PCA) is usually insidious with dogs presenting at an advanced stage of the disease. A biomarker that can facilitate early detection of TCC/PCA and improve patient survival would be useful. S100A8/A9 (calgranulin A/B or calprotectin) and S100A12 (calgranulin C) are expressed by cells of the innate immune system and are associated with several inflammatory disorders. S100A8/A9 is also expressed by epithelial cells after malignant transformation and is involved in the regulation of cell proliferation and metastasis. S100A8/A9 is up-regulated in human PCA and TCC, whereas the results for S100A12 have been ambiguous. Also, the urine S100A8/A9-to-S100A12 ratio (uCalR) may have potential as a marker for canine TCC/PCA. Aim of the study was to evaluate the diagnostic accuracy of the urinary S100/calgranulins to detect TCC/PCA in dogs by using data and urine samples from 164 dogs with TCC/PCA, non-neoplastic urinary tract disease, other neoplasms, or urinary tract infections, and 75 healthy controls (nested case-control study). Urine S100A8/A9 and S100A12 (measured by species-specific radioimmunoassays and normalized against urine specific gravity [S100A8/A9_USG; S100A12_USG], urine creatinine concentration, and urine protein concentration and the uCalR were compared among the groups of dogs.

RESULTS

S100A8/A9_USG had the highest sensitivity (96%) and specificity (66%) to detect TCC/PCA, with specificity reaching 75% after excluding dogs with a urinary tract infection. The uCalR best distinguished dogs with TCC/PCA from dogs with a urinary tract infection (sensitivity: 91%, specificity: 60%). Using a S100A8/A9_USG ≥ 109.9 to screen dogs ≥6 years of age for TCC/PCA yielded a negative predictive value of 100%.

CONCLUSIONS

S100A8/A9_USG and uCalR may have utility for diagnosing TCC/PCA in dogs, and S100A8/A9_USG may be a good screening test for canine TCC/PCA.

Usefulness of urine cytology as a routine work-up in the detection of recurrence in patients with prior non-muscle-invasive bladder cancer: practicality and cost-effectiveness

Purpose

To investigate the usefulness of urine cytology in the detection of tumor recurrence in terms of practicality and cost-effectiveness.

Materials and Methods

We retrospectively analyzed 393 patients who underwent transurethral resection of bladder tumor (TURBT) for non-muscle-invasive bladder cancer (NMIBC) from January 2010 to June 2013. All patients underwent cystoscopy, urine cytology, urinalysis, and computed tomography (CT) at 3 and 6 months after TURBT. In 62 cases, abnormal bladder lesions were identified on cystoscopy within 6 months. Suspicious lesions were confirmed pathologically by TURBT or biopsy. Patients were grouped by modalities: group I, urine cytology; group II, CT; group III, urinalysis; group IV, urine cytology plus CT; group V, urine cytology plus urinalysis; group VI, CT plus urinalysis; group VII, combination of all three modalities. Each group was compared by cost per cancer detected.

Results

Forty-nine patients were confirmed to have tumor recurrence and 13 patients were confirmed to have inflammation by pathology. The overall tumor recurrence rate was 12.5% (49/393) and recurrent cases were revealed as NMIBC. Sensitivity in group I (24.5%) was lower than in group II (55.1%, p=0.001) and group III (57.1%, p<0.001). However, in group VII (77.6%), the sensitivity was statistically similar to that of group VI (75.5%, p=0.872). Under the Korean insurance system, total cost per cancer detected for group VII was almost double that of group VI (p=0.041).

Conclusions

Routine urine cytology may not be useful for follow-up of bladder cancer in terms of practicality and cost-effectiveness. Application of urine cytology needs to be adjusted according to each patient.

S100 protein family in human cancer

S100 protein family has been implicated in multiple stages of tumorigenesis and progression. Among the S100 genes, 22 are clustered at chromosome locus 1q21, a region frequently rearranged in cancers. S100 protein possesses a wide range of intracellular and extracellular functions such as regulation of calcium homeostasis, cell proliferation, apoptosis, cell invasion and motility, cytoskeleton interactions, protein phosphorylation, regulation of transcriptional factors, autoimmunity, chemotaxis, inflammation and pluripotency. Many lines of evidence suggest that altered expression of S100 proteins was associated with tumor progression and prognosis. Therefore, S100 proteins might also represent potential tumor biomarkers and therapeutic targets. In this review, we summarize the evidence connecting S100 protein family and cancer and discuss the mechanisms by which S100 exerts its diverse functions.

Effect of PTEN Gene Mutations and Environmental Risk Factors on the Progression and Prognosis of Bladder Cancer

BACKGROUND

Bladder cancer is the most frequent genitourinary malignancy in Iran. Environmental and genetic factors are the two factors linked with bladder cancer expansion. The aim of this study was to investigate the role of PTEN gene and environmental risk factors on the progression and prognosis of bladder cancer.

METHODS

We evaluated 55 tumor specimens and 66 bladder mucosa samples of non-cancerous patients between 2011 and 2013. All samples were analyzed for PTEN mutations using PCR and direct DNA sequencing methods. Demographic data collected, were analyzed using SPSS version 19.0 software and a P value of < 0.05 was considered statistically significant.

RESULTS

Of the 55 patients examined, tumor stage was T1, T2 (T2a, T2b) in 34 (61.8%) and 21 (38.2%) and tumor grade was high, low in 34 (61.8%) and 21 (38.2%), respectively. No mutations in the PTEN gene were found in patients with bladder cancer and control. Among the risk factors studied, only the occupation and history of urinary tract stones, were significantly associated with bladder cancer (P value<0.05). However, other risk factors did not show such a relationship.

CONCLUSION

No mutation was found in PTEN gene of patients with bladder cancer. Therefore, mutations in this gene cannot predict the prognosis and progression of urothelial bladder cancer. On the other hand, significant rela-tionship was found between occupation and urinary stones with bladder cancer. This communication reflects the im-pact of these factors on the risk of bladder cancer.

Cell-Free microRNA-214 From Urine as a Biomarker for Non-Muscle-Invasive Bladder Cancer

PURPOSE

MicroRNAs are small noncoding RNAs and microRNA-214 (miR-214) has been associated with the inhibition of cancer cell growth, migration, and invasion. The aim of this study was to investigate whether cell-free miR-214 isolated from urine could be used as a biomarker for non-muscle-invasive bladder cancer (NMIBC).

MATERIALS AND METHODS

A total of 138 patients with primary NMIBC and 144 healthy normal controls were enrolled in this study. By use of quantitative polymerase chain reaction (PCR), the urinary levels of cell-free miR-214 were measured and the clinicopathological parameters of patients with NMIBC were compared with those of the controls.

RESULTS

The urinary levels of cell-free miR-214 were significantly higher in the NMIBC patients than in the controls (20.08±3.21 vs. 18.96±2.68, p=0.002). However, the urinary levels of cell-free miR-214 were neither graded nor staged for the NMIBC patients (p>0.05, each). When we compared the urinary levels of cell-free miR-214 according to clinical outcomes, patients with recurrence had lower levels of miR-214 than did those with no recurrence (19.24±2.67 vs. 20.41±3.41, p=0.023). By contrast, there were no significant differences in the urinary level of cell-free miR-214 between the NMIBC patients showing progression and those showing no progression (p=0.919). Multivariate Cox regression analysis revealed that urinary levels of cell-free miR-214 were an independent predictor of NMIBC recurrence (hazard ratio, 2.011; 95% confidence interval, 1.027 to 3.937; p=0.041).

CONCLUSIONS

Urinary levels of cell-free miR-214 could be an independent prognostic parameter for NMIBC recurrence. Thus, urinary cell-free microRNA-214 might be a useful prognostic marker for NMI BC.

FAM70B as a Novel Prognostic Marker for Cancer Progression and Cancer-Specific Death in Muscle-Invasive Bladder Cancer

Purpose

To validate whether FAM70B, which was found in our micro-array profiling as a prognostic marker for cancer survival, could accurately predict prognosis in patients with muscle-invasive bladder cancer (MIBC).

Materials and Methods

A total of 124 patients with MIBC were enrolled in this study. The FAM70B expression level was analyzed by real-time polymerase chain reaction by using RNA from tumor tissues. The prognostic effect of FAM70B was evaluated by Kaplan-Meier analysis and a multivariate Cox regression model.

Results

Kaplan-Meier estimates showed a significant difference in progression-free survival (log-rank test, p=0.011) and cancer-specific survival (log-rank test, p=0.017) according to FAM70B gene expression level. By multivariate Cox regression analysis, high FAM70B expression was predictive of cancer progression (hazard ratio [HR], 2.115, p=0.013) and cancer-specific death (HR, 1.925; p=0.033). In the subgroup analysis, high expression of FAM70B was associated with poor cancer-specific survival, progression-free survival, and overall survival in the patients who underwent cystectomy (log-rank test, p=0.013, p=0.036, p=0.005, respectively). In the chemotherapy group, FAM70B expression was associated with cancer-specific survival and progression-free survival (log-rank test, p=0.013, p=0.042, respectively). Moreover, high FAM70B expression was associated with shorter cancer-specific survival in localized or locally advanced tumor stages (log-rank test, p=0.016).

Conclusions

We confirmed the significance of FAM70B as a prognostic marker in a validation cohort. Therefore, we propose that the FAM70B gene could be used to more precisely predict cancer progression and cancer-specific death in patients with MIBC.

Immunohistochemical expression of Annexin A2 and S100A proteins in patients with bulky stage IB-IIA cervical cancer treated with neoadjuvant chemotherapy

OBJECTIVE

Abnormal expression of Annexin A2 and S100A proteins has been reported to induce sensitivity/resistance to chemotherapy in a variety of cancers. The aim of this study was to evaluate the significance of Annexin A2 and S100A protein expression to predict response to neoadjuvant chemotherapy and prognostic significance of these protein expressions in bulky stage IB-IIA cervical cancer patients.

METHODS

Paired tumor samples (pre- and post-chemotherapy) were obtained from 68 patients who were treated with cisplatin-based neoadjuvant chemotherapy and radical hysterectomy at our hospital from 2006 to 2011. The expression of Annexin A2 and S100A proteins was analyzed by immunohistochemistry.

RESULTS

Thirty-six patients were identified as chemotherapy-response and 32 were non-response. (a). Protein expression in tumor cells: (1). Exposure of tumor cells to chemotherapy results in a change of Annexin A2 and S100A expression (P<0.05). (2). Annexin A2, S100A8 and S100A9 protein expression correlates with tumor response to chemotherapy (P<0.05). (b). Protein expression in stromal cells: (1). Expression of Annexin A2, S100A8 and S100A9 was increased, but S100A2 and S100A4 was decreased after exposure to chemotherapy (P<0.05). (2). Only S100A4 expression was associated with response to chemotherapy (P<0.05). Multivariate analysis revealed that tumor size (P=0.022), differentiation (P=0.000), Annexin A2 expression in stromal cells (P=0.009), and S100A8 expression in tumor cells (P=0.008) were independent prognostic factors for progression-free survival of cervical cancer patients.

CONCLUSIONS

Expression of some of the measured proteins in tumor and stromal cells correlates with chemotherapy exposure, response to therapy, and progression-free survival.

Ras association domain family 1A: a promising prognostic marker in recurrent nonmuscle invasive bladder cancer

The aim of this study was to investigate the value of RASSF1A methylation as a prognostic marker in bladder cancer. RASSF1A hypermethylation from 301 specimens of primary BC tissue was assessed using methylation-specific PCR. Among patients with recurrent NMIBC, RASSF1A methylation was identified as an independent predictor of cancer progression.

INTRODUCTION

Aberrant methylation of promoter CpG islands is an important inactivation mechanism of tumor suppressors and tumor-related genes. Ras association domain family 1A (RASSF1A) promoter hypermethylation was shown to be associated with bladder cancer (BC), but its prognostic value remains unclear. The aim of the present study was to investigate the value of RASSF1A methylation as a prognostic marker in BC.

MATERIALS AND METHODS

Primary BC tissues were obtained from 301 patients and included 186 specimens of nonmuscle invasive bladder cancer (NMIBC) and 115 specimens of muscle invasive bladder cancers (MIBC). RASSF1A hypermethylation was assessed using methylation-specific polymerase chain reaction (MS-PCR). The association between RASSF1A hypermethylation and clinicopathologic features, and the prognostic significance of RASSF1A hypermethylation were evaluated by Kaplan-Meier and multivariate Cox regression analyses.

RESULTS

RASSF1A promoter hypermethylation was detected in 33.6% of BCs and occurred more frequently in MIBC (46.1%) than in NMIBC (25.8%) (P < .001). In NMIBC, RASSF1A methylation was associated with advanced tumor stage (P = .026) and high grade (P < .001). Among patients with recurrent NMIBC, RASSF1A methylation was associated with shorter time to progression by Kaplan-Meier analysis (log-rank test; P = .004) and identified as an independent predictor of cancer progression by multivariate Cox regression analysis (hazard ratio [HR], 8.559; P = .014).

CONCLUSIONS

Our results suggest that methylated RASSF1A may be a potential prognostic marker in patients with recurrent NMIBC.

Cryptotanshinone down-regulates androgen receptor signaling by modulating lysine-specific demethylase 1 function

Development and progression of prostate cancer are intimately associated with androgen receptor (AR) signaling. The emergence of hormone-refractory prostate cancer and consequent failure of conventional androgen deprivation therapies make it necessary to bypass hormonal resistance by targeting the same signaling pathway at new intervention points. In our study, we showed that cryptotanshinone inhibited the growth of AR-positive prostate cancer cells, suggesting that cryptotanshinone affected AR function. Cryptotanshinone also profoundly inhibited the transcriptional activity of AR and suppressed the expression of several AR-target genes at the mRNA and the protein levels. At the molecular level, cryptotanshinone disrupted the interaction between AR and lysine-specific demethylase 1 (LSD1), and inhibited the complex of AR and LSD1 to the promoter of AR target genes without affecting the protein degradation and translocation of AR. Cryptotanshinone increased the mono-methyl and di-methylation of Histone H3 lysine 9 (H3K9), a repressive histone marker which is demethylated and activated by LSD1. These data suggest that cryptotanshinone functions via inhibition of LSD1, a protein that promotes AR-dependent transcriptional activity via derepression of H3K9. In summary, we describe a novel mechanism whereby cryptotanshinone down-regulates AR signaling via functional inhibition of LSD1-mediated demethylation of H3K9 and represses the transcriptional activity of AR. Our data suggest that cryptotanshinone can be developed as a potential therapeutic agent for prostate cancer.

RUNX3 methylation as a predictor for disease progression in patients with non-muscle-invasive bladder cancer

BACKGROUND AND OBJECTIVES

We have previously reported that RUNX3 inactivation by promoter hypermethylation correlated with advanced disease and poor clinical outcome in bladder cancer. In this study, we examined primary tumors from non-muscle-invasive bladder cancer (NMIBC) patients in order to investigate the relationship between RUNX3 methylation and disease progression.

METHODS

The association between the hypermethylation of RUNX3 and clinicopathological characteristics of 186 NMIBC samples was analyzed using methylation-specific polymerase chain reaction (MS-PCR).

RESULTS

RUNX3 methylation was associated with increased tumor stage, grade, and number of tumors (each P < 0.05). Kaplan-Meier estimates revealed significant differences in time to recurrence and progression based on RUNX3 methylation status (P = 0.043 and 0.006, respectively). RUNX3 methylation was an independent predictor of NMIBC progression on univariate and multivariate analysis. Combining tumor grade and RUNX3 methylation status demonstrated that patients with G3 tumors with RUNX3 methylation had a worse progression-free survival compared with the patients with lower-grade or unmethylated tumors [hazard ratio (HR), 19.450].

CONCLUSIONS

RUNX3 methylation status predicted the risk of NMIBC progression independently of tumor stage. In conjunction with tumor grade, RUNX3 methylation status in patients with NMIBC strongly predicts disease progression.

Three-gene signature predicts disease progression of non-muscle invasive bladder cancer

The clinical grades and staging methods currently employed for bladder cancer (BC) are inadequate for assessing treatment outcomes for non-muscle invasive bladder cancer (NMIBC). We have developed a clinically applicable quantitative real-time PCR (qPCR) gene signature to predict the progression of NMIBC. Three genes not previously described for BC were selected from our published progression-related gene classifier data set. Data were drawn from a previous study population and from new cases. Primary NMIBC tissue specimens (n=193) were analyzed by qPCR. Risk scores were then used to rank specimens into high- and low-risk signature groups based on their gene expression. The Kaplan-Meier method and a multivariate Cox regression model were used to identify the prognostic value of the three-gene signature for both recurrence and progression. The Kaplan-Meier estimates revealed significant differences in time-to-recurrence and progression between low- and high-risk signatures (log-rank test, p=0.011 and p<0.001, respectively). The multivariate Cox regression analysis showed that the three-gene risk signature is an independent predictor of bladder tumor progression (hazard ratio, 4.268; 95% CI, 1.542-11.814; p=0.005). In conclusion, our three-gene signature was found to be closely associated with progression among patients with NMIBC.

GSTM1 tissue genotype as a recurrence predictor in non-muscle invasive bladder cancer

Tissue genotyping is more useful approach than using blood genomic DNA, which can reflect the effects of the somatic mutations in cancer. Although polymorphisms in glutathione S-transferase (GST) have been associated with the risk of bladder cancer (BC) development, few reports provide information about the prognosis of BC. We investigated glutathione S-transferase mu (GSTM1) and glutathione S-transferase theta (GSTT1) genotypes using genomic DNA from primary 165 BC tissue samples to assess the association with disease prognosis. DNA samples from tumor were analyzed by multiplex polymerase chain reaction (PCR). The results were compared with clinicopathological parameters. The prognostic significance of the GSTs was evaluated by Kaplan-Meier and multivariate Cox regression model. Kaplan-Meier estimates revealed significant differences in time to tumor recurrence according to the GSTM1 tissue genotype (P = 0.038) in non-muscle invasive bladder cancer (NMIBC). Multivariate Cox regression analysis also revealed that the tissue GSTM1 genotype (hazards ratio [HR]: 0.377, P = 0.031) was an independent predictor of bladder tumor recurrence in NMIBC. This identification of GSTM1 tissue genotype as a prognosticator for determining recurrence in NMIBC should prove highly useful in a clinical setting.