Roles of p53 and MDM2 in tumor proliferation and determination of the prognosis of transitional cell carcinoma of the renal pelvis and ureter

Evaluation of P53 and CK20 Immunohistochemical Markers in Comparison with Morphologic Findings in Low- and High-grade Urothelial Carcinomas

BACKGROUND & OBJECTIVE

Urothelial carcinoma is the seventh most common cancer in the world. The histological classification of papillary carcinoma is one of the most important determinants for its prognosis. Sometimes there is an overlap in the extent of the tumor, and the accurate microscopic diagnosis of the tumor is not always easy. The aim of this study was to evaluate P53 and CK20 immunohistochemical markers in comparison with morphologic findings in low- and high-grade urothelial carcinomas.

METHODS

For this descriptive study, urinary bladder samples were collected from 50 cancer patients who had undergone biopsy and surgery in Shohaday-e Tajrish Hospital of Tehran, Iran, during the years 2015-2016. P53 and CK20 were studied, and the demographic and histopathological characteristics of the tumor were also analysed.

RESULTS

The mean age of patients enrolled in this study (48 males and 2 females) was 65.8±11.9. Twenty-five cases presented with low-grade and 25 cases presented with high-grade papillary urothelial carcinomas. Sensitivity, specificity, and positive and negative predictive values for P53 were 48%, 80%, 70.5%, and 60.6%, respectively, while the same values for CK20 were 44%, 92%, 84.6%, and 62.2%, respectively. Immunohistochemical results were also positively correlated with the extent of the tumor.

CONCLUSION

Based on the results, P53 and CK20 may serve as specific markers for diagnosis of low- and high-grade papillary urothelial carcinoma but not sensitive. P53 and ck20 staining have also a high specificity as 80% and 92% and low sensitivity compared to the low and high morphology of papillary carcinoma, thus their positive and their staining intensity are valuable for diagnosis, but their negative results are not determinant.

Renal Epithelioid Angiomyolipoma Undergoing Aggressive Clinical Outcome: The MDM2 Expression in Tumor Cells of Two Cases

Epithelioid angiomyolipoma (EAML) has been known as a potentially malignant tumor which occasionally recur and/or metastasize to other organs, and clinically and pathologically recognized as distinct entity. However, the mechanisms of recurrence and/or metastasis (recurrence/metastasis) has still remained unknown. Here, we report two cases of renal EAML associated with recurrence/metastasis, and three cases of EAML in kidney or liver without recurrence/metastasis. According to the previous histological predictive models of EAML, the primary tumor was classified as low risk group in one of the cases with recurrence/metastasis in spite of its malignant behavior. Therefore, we considered that further investigation about the mechanisms of recurrence/metastasis in EAML is required for a malignancy prediction. We focused on some cell-cycle modulators, including mouse double minute 2 homolog (MDM2), which is ubiquitin ligase well-known to promote malignant behaviors by p53 ubiquitination and degradation, and also other cellular processes including genomic instability and epithelial-mesenchymal transition in p53-independent manners in various human malignancies. Immunohistochemical evaluation revealed that MDM2 protein expression increased stepwise throughout every steps of metastasis/recurrence in both cases, although it was negative in primary tumors. In conclusion, this is the first study demonstrating that MDM2 could play an important role in the molecular mechanisms of recurrence/metastasis of EAML. Further analyses focusing on MDM2 pathway could contribute to the identification of novel prognostic factors and/or therapeutic targets in EAML patients.

MDM2 Contributes to High Glucose-Induced Glomerular Mesangial Cell Proliferation and Extracellular Matrix Accumulation via Notch1

Murine double minute 2 (MDM2) is an E3-ubiquitin ligase critical for various biological functions. Previous data have revealed an indispensable role of MDM2 in kidney homeostasis. However, its role in glomerular mesangial cell (GMC) proliferation and extracellular matrix (ECM) accumulation during hyperglycemia condition remains unclear. In our present study, we found that MDM2 protein level was significantly upregulated in high glucose-treated GMCs, while knocking down MDM2 by siRNA could attenuate high glucose-induced ECM accumulation and GMCs proliferation. Unexpectedly, Nutlin-3a, a MDM2-p53 interaction blocker, had no benefit in protecting diabetic mice from renal impairment in vivo and in alleviating high glucose-induced ECM accumulation in vitro. Intriguingly, we found that Notch1 signaling activation was obviously attenuated by MDM2 depletion in GMCs with high glucose exposure. However, Numb, a substrate of MDM2 which suppresses Notch1 signaling, was found not to be involved in the MDM2 and Notch1 association. Moreover, our findings demonstrated that MDM2 interacted with Notch1 intracellular domain (NICD1) independent of Numb and regulated the ubiquitination status of NICD1. Collectively, our data propose a pivotal role of MDM2 in high glucose-induced GMC proliferation and ECM accumulation, via modulating the activation of Notch1 signaling pathway in an ubiquitination-dependent way.

Prognostic Genetic Signatures in Upper Tract Urothelial Carcinoma

Urothelial carcinoma is a highly heterogeneous disease that can arise throughout the entire urothelial lining from the renal pelvis to the proximal urethra. Upper tract urothelial carcinoma (UTUC) is rare, and while it shares many similarities with urothelial carcinoma of bladder (UCB), there are also significant differences between UTUC and UCB regarding clinical management and outcomes. No major advances have been made recently in the development of new systemic therapies for urothelial carcinoma, partly due to the lack of understanding of underlying molecular pathogenetic mechanisms. In the past decade, the emergence of next-generation sequencing has greatly enabled genomic characterization of tumor samples. Researchers are currently exploring a personalized approach to augment traditional clinical decision-making based on genetic alterations. In the present review, we summarize current genomic advances in UTUC and discuss the potential implications of these developments for developing prognostic and predictive biomarkers.

P53 and MDM2 Over-expression and Five-year Survival of Kidney Cancer Patients Undergoing Radical Nephrectomy--Iranian Experience

BACKGROUND

Relatively little is known with certainty about the status and role of p53 or MDM2 in predicting prognosis and survival of renal cell carcinoma. The present study aimed to determine the value of P53 and MDM2 over-expression, alone and simultaneously, to predict five-year survival of patients with kidney cancer in Iran.

MATERIALS AND METHODS

Patients with kidney cancer referred to Hasheminejad Kidney Center between 2007 and 2009, underwent radical nephrectomy and had pathology reports of clear cell, papillary or chromophobe renal cell carcinoma were included in our cohort study. Other histological types of renal cell carcinoma were not included. The patients with missed, incomplete or poor quality paraffin blocks were also excluded. Overall ninety one patients met the inclusion and exclusion criteria. To assess the histopathological features of the tumor, immunohistochemical (IHC) staining of formalin fixed, paraffin-embedded tumor samples were performed. The five-year survival was determined by the patients' medical files and telephone following-up.

RESULTS

In total, 1.1% of all samples were revealed to be positive for P53. Also, 20.8% of all samples were revealed to be positive for MDM2.The patients were all followed for 5 years. In this regard, 5-year mortality was 30.5% and thus 5-year survival was 85.3%. According to the Cox proportional hazard analysis, positive P53 marker was only predictor for patients' 5-year survival that the presence of positive p53 increased the risk for long-term mortality up to 2.8 times (HR=2.798, 95%CI: 1.176-6.660, P=0.020). However, the presence of MDM2 could not predict long-term mortality. In this regard, analysis by the ROC curve showed a limited role for predicting long-term survival by confirming P53 positivity (AUC=0.610, 95%CI: 0.471-.750, P=0.106). The best cutoff point for P53 to predict mortality was 0.5 yielding a low sensitivity (32.0%) but a high specificity (97.9%). In similar analysis, measurement of MDM2 positivity could not predict mortality (AUC=0.449, 95%CI: 0.316-.583, P=0.455).

CONCLUSIONS

The simultaneous presence of both P53 and MDM2 markers in our population is a rare phenomenon and the presence of these markers may not predict long-term survival in patients who undergoing radical nephrectomy.

Impact of p53, MIB-1 and PECAM-1 expression on the prognosis of urothelial carcinoma of the renal pelvis

OBJECTIVE

Determine whether the overexpression p53, MIB-1 and PECAM-1 of protein levels is of interest in predicting the prognosis of transitional cell carcinoma of the upper urinary tract (TCC-UUT) with the primary seat in the renal pelvis.

MATERIAL AND METHOD

A univariate and multivariate analysis was conducted for prognosis prediction in a series of 82 patients with TCC-UUT of the renal pelvis who had no metastases at diagnosis (N0/Nx M0) and were treated exclusively with nephroureterectomy. We assessed clinicopathological parameters (age, gender, tumor grade and extent, histological variety, growth pattern, vascular invasion, infiltration of the renal parenchyma, tumor necrosis) and the immunohistochemical expression of p53, MIB-1 (ki-67) and PECAM-1 (CD31) in sections performed with tissue microarray (TMA).

RESULTS

A total of 47.6% of the patients had high-grade lesions according to the USIP-WHO classification. The growth pattern was flat in 15.85%. The distribution by T category was: 3.7% pTa, 51.2% pT1, 11% pT2, 29.3% pT3 and 4.9% pT4. The mean follow-up was 46.8+38.5 (range, 4-172) months. The median survival was reached at 57 (95% CI 44-63) months. The univariate analysis revealed that survival in these patients is associated with tumor size (P=.028), histological variety (P<.0001), growth pattern (P<.0001), grade (P<.0001), pT (P=.01), vascular invasion (P=.025), necrosis (P=.004) and overexpression of p53 (P=.0006), PECAM-1 (P=.0036) and MIB-1 (P=.0038). The Cox regression model showed that high-grade (HR, 4.2; 95% CI 1.28-13.79; P=.018), flat growth pattern (HR, 2.52; 95% CI 1.05-6.03; P=.038) and p53 overexpression (HR, 2.8; 95% CI 1.22-6.44; P=.015) were independent predictors.

CONCLUSION

Histological grade, tumor growth pattern and p53 overexpression were established as the primary predictors of prognosis for primary TCC-UUT of the renal pelvis. The independent value of MIB-1 observed in other studies was not reproduced in this study.

p53 Expression as a Prognostic Factor in Upper Urinary Tract Urothelial Carcinoma: A Systematic Review and Meta-Analysis

Objective: To conduct a meta-analysis examining p53 expression as a potential risk factor in upper urinary tract urothelial carcinoma (UUT-UC) and to systematically review the available data. Methods: A comprehensive literature review was performed from January 1991 to August 2012, using search engines such as PubMed, EMBASE, Cochrane Library and KoreaMed. All retrieved references were manually reviewed, and two authors independently extracted the data. The quality of case-control and cohort studies was assessed using the Scottish Intercollegiate Guidelines Network (SIGN) checklists. Heterogeneity among studies was examined using the Q statistics and Higgins' I2 statistic. Results: Of 302 abstracts of original research studies, nine case-control trials fit our criteria for inclusion in the analysis. Of the nine articles included, four scored ‘low' and five scored ‘modest' in the quality assessment performed according to the SIGN checklists. Analysis of the correlation between different factors and p53 expression in UUT-UC showed that pathologic stage (≥pT3 or <pT3) differed significantly between the p53 and non-p53 groups (OR = 2.720, p < 0.001). Statistically significant correlations were also detected between p53 expression and histologic grade (OR = 4.507, p < 0.001) and female gender (OR = 2.724, p < 0.001). Conclusion: The results of our meta-analysis suggest that p53 expression in UUT-UC was correlated with advanced pathologic stage, high histologic grade and female gender.

Predictive value of clinicopathological markers for the metachronous bladder cancer and prognosis of upper tract urothelial carcinoma

Upper tract urothelial carcinoma (UTUC) is rare but aggressive with poor prognosis. We aimed to find effective predictive markers for recurrence and prognosis in UTUC patients. In this retrospective study, we included 88 UTUC patients treated with radical neprhoureterectomy (RNU) and analyzed their clinicopathological parameters. For study of incidence of metachronous bladder tumor, models were adjusted with inclusion of prophylactic intravesical instillation chemotherapy. The mean follow-up was 28.59 months (2 to 82 mo). Lack of gross hematuria (RR 0.060, 95%CI 0.008–0.468), tumor located at ureter (RR 0.037, 95%CI 0.004–0.378), advanced stage and higher p53 expression were independent factors for worse survival. Recurrence of bladder cancer occurred 20% of patients at median follow-up of 37.65 months (5 to 82 mo). Higher tumor grade (RR 5.998, 95%CI 1.359–26.479) and presence of ipsilateral non-functioning kidney at diagnosis (RR 5.982, 95%CI 1.338–26.750) were predictors for recurrence. The present study identified several parameters with predictive value in the prognosis and intravesicle recurrence in UTUCand shed light on the better monitoring and management of the disease.

Immune expression of E-cadherin and α, β and γ-Catenin adhesion molecules and prognosis for upper urinary tract urothelial carcinomas

INTRODUCTION

Cell adhesion molecules (CAM) are required for maintaining a normal epithelial phenotype, and abnormalities in CAM expression have been related to cancer progression, including bladder urothelial carcinomas. There is only one study that correlates E-cadherin and Α-, Β- and y-catenin expression with prognosis of upper tract urothelial carcinomas. Our aim is to study the pattern of immune expression of these CAMs in urothelial carcinomas from the renal pelvis and ureter in patients who have been treated surgically. Our goal is to correlate these expression levels and characteristics with well-known prognostic parameters for disease-free survival.

MATERIALS AND METHODS

We evaluated specimens from 20 patients with urothelial carcinomas of the renal pelvis and ureter who were treated with nephroureterectomy or ureterectomy between June 1997 and January 2007. CAM expression was evaluated by immunohistochemistry in a tissue microarray and correlated with histopathological characteristics and patient outcomes after a mean follow-up of 55 months.

RESULTS

We observed a relationship between E-cadherin expression and disease recurrence. Disease recurrence occurred in 87.5% of patients with strong E-cadherin expression. Only 50.0% of patients with moderate expression and 0% of patients with weak or no expression of E-cadherin had disease recurrence (p = 0.014). There was also a difference in disease-free survival. Patients with strong E-cadherin expression had a mean disease-free survival rate of 49.1 months, compared to 83.9 months for patients with moderate expression (p = 0.011). Additionally, an absence of Α-catenin expression was associated with tumors that were larger than 3 cm (p = 0.003).

CONCLUSIONS

We demonstrated for the first time that immune expression of E-cadherin is related to tumor recurrence and disease-free survival rates, and the absence of Α-catenin expression is related to tumor size in upper tract urothelial carcinomas.

Expression of p53 in upper urinary tract urothelial carcinoma

The management of upper urinary tract urothelial carcinoma (UUT-UC) is controversial. Radical nephroureterectomy is a major undertaking and has obvious shortcomings in the presence of renal impairment and solitary kidneys, whereas endoscopic management can be associated with a risk of disease progression. There is a pressing need for reliable predictive biomarkers to refine patient selection for renal conservation. p53 is the most frequently investigated molecular marker in UUT-UC. Of the 24 papers published on the subject, expression of p53 is a significant univariate prognostic marker in 12 publications, representing seven unique cohorts. However, multivariate analysis demonstrates that p53 expression is of independent prognostic significance in only five studies, all of which contain potential statistical bias. The currently available data do not, therefore, support a role for p53 in this regard, and suggest a need for prospective large-scale collaborative studies using standardized methods of p53 detection and statistical analysis.

The prognostic value of p53, Ki-67 and matrix metalloproteinases MMP-2 and MMP-9 in transitional cell carcinoma of the renal pelvis and ureter

AIM

To investigate the prognostic and predictive relevance of p53 protein, Ki-67 antigen, MMP-2 and MMP-9 in patients with transitional cell carcinoma (TCC) of the upper urinary tract.

METHODS

The expression of p53 protein, Ki-67 antigen, MMP-2 and MMP-9 was examined by immunohistochemistry in 69 patients with TCC of the upper urinary tract. Correlation of p53, Ki-67, MMP-2 and MMP-9 over-expression with conventional pathological parameters and patient survival was examined.

RESULTS

p53 over-expression was significantly correlated with histological grade (P < 0.05), but not with pathological stage, vascular invasion, lymphatic invasion or lymph node metastasis. Ki-67 over-expression was significantly correlated with stage, grade, lymphatic invasion and vascular invasion (P < 0.05). In survival analyses, Ki-67 over-expression was a significant prognostic factor in the univariate analysis (P < 0.05), but it did not have a significant impact on survival in the multivariate analysis. Ki-67 labeling index was a significant prognostic factor in patients with a low p53 labeling index, but not in patients with a high p53 labeling index.

CONCLUSION

Ki-67 over-expression is of prognostic value in TCC of the upper urinary tract, while p53, MMP-2 and MMP-9 are of limited value.

Renal cancer: cytogenetic and molecular genetic aspects

To date, much progress has been made in the fields of cytogenetics and molecular genetics of renal tumors. The previous and recent findings have delineated the characteristics of the various tumors, particularly the cytogenetic and molecular differences that exist between papillary and nonpapillary clear cell renal cell carcinomas (RCCs). At the same time, new cytogenetic subtypes have emerged [e.g., t(X;1)] in subtypes of RCC, while in others (e.g., Wilms tumors) several new cytogenetic abnormalities and consequent molecular involvement have been found. In addition to Wilms tumor, papillary RCC, and clear-cell RCC, cytogenetic and fluorescence in situ hybridization analyses have been performed on several other tumors of the kidney, including chromophobic carcinoma, metanephric adenoma, collecting duct carcinoma, transitional cell carcinoma, congenital mesoblastic nephroma, and malignant rhabdoid tumors of the kidney. This review is therefore intended to present a concise update on the cytogenetic and molecular data on renal tumors, focusing mainly on the clinical usefulness of the findings reported in the literature.