Current approaches for identifying high-risk non-muscle invasive bladder cancer

Bladder cancer screening: The new selection and prediction model

The objective of this study was to offer new approach for selection of persons with asymptomatic bladder cancer (BC) and highly risky persons for the BC occurrence. Also, it is a part of the BC screening protocol (study is ongoing). Study populations were 100 newly diagnosed (diagnosis maximum 1-year old) males with BC and 100 matched (by sex and age ±5 years) controls (not oncology patients from the same hospital). A hospital based, matched case-control study was done. Statistical analysis comprised of four steps: t-test, univariate logistic regression, multivariate logistic regression, and scoring. The fifth step comprised of two changes, deleting one variable and addition of another variable. Six variables were statistically significant: Caucasian men over 45 years age, tobacco smoking over 40 pack-years, occupational and/or environmental exposure to the proved BC carcinogens over 20 years, macrohematuria, difficulty urinating, BC in relatives up to fourth degree of kinships, and they were used for an easy and fast selection of the individuals with high risk for BC occurrence and BC asymptomatic patients (optimal selection at the population level). The final results showed highly significant probability (p < 0.001), with area under ROC curve of 0.913, negative predictive values of 89.7% (95% CI 10.3-100%), and a specificity of 78%. Positive predictive value was 80.5% (95% CI 19.5-100%) and a sensitivity of 91%. It is possible to recruit asymptomatic BC patients (primary prevention) by using this model, as well as persons with high risk for BC occurrence (primordial prevention). This study is the first part of the BC screening protocol and the second part of the BC screening protocol study is ongoing (urine analysis).

Can serum matrix metalloproteinase-9 and SMAD-2 levels predict lamina propria invasion in bladder urothelial carcinoma?

INTRODUCTION

Matrix metalloproteinase-9 (MMP-9) has a role in the destruction of lamina propria (LP) of the bladder wall and SMAD-2 promotes cell-to-cell adhesion. This study aimed to investigate the association between LP invasion and serum protein and mRNA expression levels of MMP-9 and SMAD-2 in bladder cancer (BC) patients.

METHODS

Serum samples were taken from 57 patients with suspicious BC before TUR-BT (Group 1) and 20 patients with benign diseases as control (Group 2). The mRNA expression and serum protein levels of MMP-9 and SMAD-2 were analyzed using Real-Time PCR and ELISA methods, respectively. The comparison of protein and mRNA expression levels of MMP-9 and SMAD-2 were done statistically between Group 1 and 2, as well as for different T stages of BC.

RESULTS

The protein levels of MMP-9 (2448 vs 637.5 pg/mL, P = .0001) and SMAD-2 (6.85 vs 1.61 P = .0001) were significantly higher in Group 1 compared to Group 2. The mRNA expression levels of MMP-9 (P = .89) and SMAD-2 (P = .99) did not significantly differ between the groups. The protein levels of MMP-9 in T1 patients were significantly higher from both of pTa patients (P = .018) and pT2 (P = .02). The protein levels of SMAD-2 were not statistically different between T stages. Similarly, the mRNA expression levels of MMP-9 and SMAD-2 were not different between T stages.

CONCLUSIONS

The protein levels of MMP-9 and SMAD-2 were increased in BC patients while mRNA expressions were not different. Furthermore, the increased protein level of MMP-9 in T1 patients was more pronounced which may be related to LP invasion of the tumor.

Individual patient risk of progression of urinary bladder papillary tumors estimated from biomarkers at initial transurethral resection of bladder tumor

OBJECTIVE

To determine if individual, instead of group, patient progression risk could be predicted using p53, Ki67 and CK20 biomarker percentage values at initial transurethral resection of bladder tumor specimens.

METHODS

This was an observational study where biomarkers were measured with no knowledge of tumor outcome. Initial bladder tumor specimens were classified as non-invasive and invasive to sub-epithelium (pT1). Percentages of stained biomarker cells were tested as progression predictors from non-invasive to pT1 and pT1 to pT2. Progression probability was correlated with biomarker percentages resulting in a regression equation.

RESULTS

We studied 112 patients (median age = 67, range 37-91, males 83/112 (73%), with median follow-up of 39 months (range 1.7-140). Mean biomarker values were higher in stage pT1 than in non-invasive (all p < 0.001). Cut-off points separating progression from non-progression groups in stage pT1 were higher than in non-invasive for all biomarkers. Correlation R values for progression probability vs. biomarker percentages varied from 0.7 to 0.9 (all p < 0.001), regression slopes from 0.1 to 0.8 and intercepts from 11 to 35. A novel individual progression probability was calculated as the product of biomarker percentage of stained cells and slope, plus the prevalence-adjusted intercept.

CONCLUSIONS

Identification of individual risk of progression in patients with non-muscle-invasive bladder tumors was possible using p53- and Ki67-derived progression probability using a regression equation. Combining biomarker-derived progression probability to tumor stage pT1 improves progression to pT2 predictive accuracy.

Fatty acid synthase, Her2/neu, and E2F1 as prognostic markers of progression in non-muscle invasive bladder cancer

Non-muscle-invasive bladder cancer (NMIBC) is a heterogeneous disease which has an unpredictable risk of progression to muscle-invasive bladder cancer (MIBC). The selection of patients who may benefit from early radical intervention is a challenge. To define the useful prognostic markers for progression, we analyzed the immunohistochemical expression of fatty acid synthase (FASN), Her2/neu, and E2F1 in 60 cases of NMIBC who underwent TURBT and adjuvant intravesical bacillus-Calmette-Guérin (BCG). Their predicting role for tumor recurrence, progression, recurrence-free survival (RFS) and progression-free survival (PFS) was analyzed. High FASN expression was observed in 56.7% (34/60) of NMIBC cases, and FASN expression was significantly associated with the tumor size, grade, and tumor stage (p = 0.003, p < 0.001, p < 0.0001 respectively). Positive Her2/neu was noted in 18.3% (11/60) of the cases, and its expression was significantly associated with the tumor size, histologic grade, and tumor stage (p = 0.001, p = 0.002, p = 0.011 respectively). High E2F1 expression was detected in 40% of the cases, and it was associated with tumor size, histologic grade, and tumor stage (p < 0.001 for each). Analysis of follow-up period revealed that NMIBC with high FASN, positive Her2/neu, and high E2F1 expression exhibited a potent relation with tumor progression, shorter RFS, and poor PFS. Conclusions: High FASN, Her2/neu, and E2F1 are considered as adverse prognostic factors of tumor recurrence and progression in NMIBC and these patients should be followed carefully. Therefore, we suggest that FASN, Her2/neu, and E2F1 should be considered and evaluated during the selection of the appropriate management strategy for NMIBC patients.

Long noncoding RNA neuroblastoma-associated transcript 1 gene inhibits malignant cellular phenotypes of bladder cancer through miR-21/SOCS6 axis

Bladder cancer (BC) is one of the most common tumors in the urinary system. Noncoding RNAs are considered to take part in cellular phenotypes and are emerging as diagnostic and prognostic biomarkers of BC. The aim of this study is to investigate the clinical significance of neuroblastoma- associated transcript 1 (NBAT1) gene and its effects on malignant cellular phenotypes in BC. NBAT1 gene was low-expressed in BC tissues and cell lines and its low-expression was related with high pathological grade and metastasis of BC. Upregulation of NBAT1 gene depressed cell viability and invasiveness of KK47 and T24 cells and arrested KK47 and T24 cells at G1 stage. In addition, NBAT1 could target silence the expression of miR-21-5p in RNA-induced silencing complex-dependent manner. KK47 and T24 cells with miR-21-5p knockdown showed reduced cell viability, G1-stage arrest, and depressed invasiveness. MiR-21-5p mediates the regulatory effects of NBAT1 on malignant cellular phenotypes of BC cells. Moreover, SOCS6 gene was a target gene of miR-21-5p, and miR-21-5p modulated malignant cellular phenotypes of KK47 and T24 cells through targeted silencing of SOCS6. In conclusion, low-expression of NBAT1 is associated with the progress and metastasis of BC, and NBAT1 inhibits malignant cellular phenotypes through miR-21-5p/SOCS6 axis in BC. Our findings help to elucidate the tumorigenesis of BC, and future study will provide a novel therapeutic target for BC.