Can p53 nuclear over-expression, Bcl-2 accumulation and PCNA status be of prognostic significance in high-risk superficial and invasive bladder tumours?

Human papilloma virus and p53 expression in bladder cancer in Egypt: relationship to schistosomiasis and clinicopathologic factors

The aim of the current study was to compare the role of p53 and human papillomavirus (HPV) in schistosomiasis-related and schistosomiasis-unrelated carcinoma of the urinary bladder. To achieve this aim, we investigated 114 bladder carcinomas for p53 oncoprotein expression by immunohistochemistry and for human papillomavirus by in situ hybridization technique. The results revealed that 64 tumors (56.1%) were schistosomiasis-associated. Sixty seven (58.8%) were transitional cell carcinomas and 32 (28%) were squamous cell carcinomas. The remaining 15 tumors (13.2%) included adenocarcinomas and sarcomatoid carcinomas. In both schistosomiasis-associated and non-associated carcinomas, p53 oncoprotein expression was significantly higher in poorly differentiated tumors. However, it was significantly higher in locally more invasive tumors in the schistosomal carcinomas only. HPV types 16/18 could be detected in 1 of the 114 bladder carcinomas (0.95%), which was schistosomiasis-related squamous cell carcinoma in situ. These results suggest that p53 immunohistochemistry can be a prognostic factor in both schistosomal and nonschistosomal bladder cancer. More importantly, HPV does not seem to play a role in the pathogenesis of either type of bladder cancer in our country.

P53 as a prognostic marker for bladder cancer: a meta-analysis and review

BACKGROUND

P53 is the most widely investigated molecular marker in bladder cancer. We aimed to review comprehensively the evidence for use of changes in P53 to predict bladder-cancer recurrence, progression, and mortality.

METHODS

We reviewed 168 publications from 117 studies. Estimates of significance were extracted from association tests, and hazard ratios with 95% CI from actuarial curves and Cox regression analyses. A meta-analysis was done on the studies that applied Cox models.

FINDINGS

The methods used to assess significance varied widely between studies. 27% (nine of 34) of studies that assessed the prognostic value of P53 overexpression in recurrence by use of multivariate tests showed a significant association. The corresponding values for progression and mortality were 50% (12 of 24) and 29% (ten of 35), respectively. In the studies that used Cox models, the overall risk of recurrence was 1.6 (95% CI 1.2-2.1), of progression was 3.1 (1.9-4.9), and of mortality was 1.4 (1.2-1.7). These findings could be overestimates because of publication and reporting bias.

INTERPRETATION

After 10 years of research, evidence is not sufficient to conclude whether changes in P53 act as markers of outcome in patients with bladder cancer.

Valor pronóstico de progresión de las moléculas reguladoras del ciclo celular en tumores vesicales T1G3

INTRODUCTION AND OBJECTIVE

Bladder tumor T1G3 constitutes the group of superficial tumors more aggressive. New prognostic factors in the field of the cytogenetics and molecular biology have been analyzed, with often contradictory results, being little the specific works in tumors T1G3. Our objective is to determine if in this group of tumors the immunohistochemical markers present predictive value of clinically useful progression, and therefore with validity to indicate more suitable a precocious therapeutic attitude.

MATERIAL AND METHODS

Retrospective study of a series of 83 patients affected of bladder tumor T1G3, on which we analyzed a total of 14 variables; between the new predictive factors: the immunohistochemical determination of regulating proteins of the cellular cycle: p53, p21 and bcl-2, as well as the Ki-67 protein like marker of cellular proliferation. By means of logistic regression analysis we establish the independent prognostic variables for tumorlike progression.

RESULTS

The cut point established for Ki67 and p53 was 40% of inmmunomarked cells, 20% for p21 and 10% for Bcl-2. The univariant analysis showed different rates from progression and free times of progression based on the immunohistochemistry of Ki67 and p53: nevertheless, the logistic regression demonstrated that single the immunohistochemistry of p53 presented independent predictive value.

CONCLUSIONS

The determination of p53 presents predictive value of clinically useful progression in bledder tumors T1G3, so that its determination can constitute a essential factor in the strategies of treatment of these tumors.

Muscle invasive schistosomal squamous cell carcinoma of the urinary bladder: frequency and prognostic significance of p53, BCL-2, HER2/neu, and proliferation (MIB-1)

Muscle invasion is the usual presentation of schistosomal squamous cell carcinoma of the urinary bladder. It is unclear whether this invasive behavior is secondary to the aggressive nature of the disease or to delay in diagnosis. Fixed paraffin-embedded hematoxylin and eosin-stained sections of 15 cystectomy specimens from 15 patients (14 males, 1 female) (age range, 40 to 67 years), histologically confirmed as schistosomal squamous cell carcinoma, were assessed for grade (G1, n = 3; G2, n = 7; G3, n = 5) and pathological stage (PT category: PT2, n = 4; PT3a, n = 9; PT3b, n = 2). Immunostaining was performed for mutant p53, bcl-2, HER2/neu, and MIB-1 (proliferation), using steam antigen retrieval and an avidin-biotin complex method. Frequency of strong immunoreactivity was high for mutant p53 (73%) and MIB-1 (87% intermediate or high) but low for bcl-2 (20%) and HER2/neu (27%). There was no significant correlation of any of the four markers with either grade or stage. Hence, schistosomal bladder squamous cell carcinoma is felt to be an aggressive carcinoma de novo. The high frequency of mutant p53 expression (73%) and an intermediate to high proliferation index (87%) suggests this. The lack of correlation between histological grade and all four markers studied suggests that grading is not of prognostic value.

[Transitional bladder carcinoma TaG1: role of the EGFr tyrosin kinase activation in the cellular proliferation]

BACKGROUND AND OBJECTIVE

The purpose of this work was to study if the expression of EGFr oncoprotein and the rate of tumoral cell proliferation in TaG1 transitional bladder carcinoma were related and if this relationship influences the potential aggressivity of the neoplasia.

PATIENTS AND METHOD

Twenty-eight patients with TaG1 (non-invasive papillary and well differentiated) transitional bladder carcinoma were randomly selected. EGFr was determined by a semiquantitative immunohistochemical method in three intensity levels. The proliferative tumoral cell activity was determined by the PCNA index, that is, the relation between the total number of tumor cells and the number of tumor cells with nuclear PCNA-immunoreactivity expressed in percentage.

RESULTS

The rate of cellular tumour proliferation (PCNA index) was significantly higher in those tumors with EGFr's greater expression (p=0.005). The EGFr expression was associated with tumor recurrence (p=0.012).

CONCLUSIONS

The major expression of EGFr oncoprotein in tumours with higher rate of cell proliferation indicates that it may be influenced by the activity of such oncoprotein. The binding of a ligand to the EGFr leads to intracellular tumor proliferation, hence possibly favouring a more aggressive biological behavior.

Patterns of multiple recurrences of superficial (Ta/T1) transitional cell carcinoma of bladder and effects of clinicopathologic and biochemical factors

BACKGROUND

Although multiple sequential recurrences are one of the most important characteristics of superficial transitional cell carcinoma (TCC) of the bladder, few studies have examined multiple sequential recurrence patterns and the clinicopathologic and biochemical factors associated with these patterns.

METHODS

Two hundred seventy superficial TCC bladder carcinoma patients were followed. Clinical, pathologic, and tumor marker (p53, MIB-1, bcl-2, c-erb B-2, and epidermal growth factor receptor) data were collected at baseline and during followup. The Kaplan-Meier (KM) method was used to describe multiple recurrences. The Wei, Lin, and Weissfeld (WLW) marginal proportional hazards model was used to assess the effects of clinicopathologic and immunohistochemic factors on multiple recurrences.

RESULTS

Among the 270 patients, 126 (46.7%) had one or more recurrences, 38 (14.1%) had two or more recurrences, and 14 (5.2%) had three or more recurrences during the followup. The median times for the first, the second, and the third recurrences were 23 months, 15 months, and 13 months, respectively. In KM analysis, Stage T1, higher grades, and Ki-67 stain positivity were associated with the first recurrence, and p53 stain positivity was marginally significant. Other markers were not significant. For the second recurrence, only p53 stain positivity was significant. In multivariate analysis (WLW method), stage was significantly associated with the first recurrence (risk ratio [RR] = 2.03), and Ki-67 was marginally significant (RR = 1.49). For the second recurrence, only p53 positivity was statistically significant (RR = 2.73).

CONCLUSIONS

Among superficial TCC bladder carcinoma patients, multiple recurrences are common phenomena. The time for recurrence becomes shorter as the number of recurrences increases. In addition to tumor stage and grade, Ki-67 can be used to identify patients at high risk for a first recurrence; and p53 can be used to identify patients at high risk for a second recurrence.

[Prognostic value of P53, Ki67, and Rb protein in infiltrating bladder tumors]

OBJECTIVES

To determinate whether increased expression of the p53 and Ki67 and the of the tumour suppressor gene retinoblastoma (prot Rb), in an immunohistochemistry study, were associated with relapse in invasive bladder cancer.

MATERIALS AND METHODS

47 patients with invasive bladder cancer. 42 men and 5 women. Mean age 63 years old. Relapse in 19 patients (40%). Mean time until recurrence 8.5 months. p53 and Ki67 were study in 47 patients and prot Rb in 40 patients.

RESULTS

p53: Mean expression 41%. There were significant differences in the increased expression of p53 between patients with and without relapse (p = 0.03). A statistically significant association was then observed between patients with p53 > 20% (vs p53 < 20%) and adverse outcome of the disease (p = 0.04). Ki67 and prot Rb: There were no significant differences in relapse and progression free survival between Ki67 > 40% (vs Ki67 < 40%) and prot Rb < 10% (vs prot Rb > 10%). p53 expression showed a statistically significant correlation with Ki67 and prot Rb.

CONCLUSION

p53 is a good prognostic marker for the relapse and progression free survival in invasive bladder cancer.

Molecular aspects of bladder cancer III. Prognostic markers of bladder cancer

The current pathological and clinical parameters provide important prognostic information, yet still have limited ability to predict the true malignant potential of most bladder tumors. In the last years, investigation of the basic mechanisms involved in carcinogenesis and tumor progression by molecular biology has provided a host of markers which are of potential diagnostic or prognostic value for bladder carcinoma. These markers may serve as tools for early and accurate prediction of tumor recurrence, progression and development of metastases and for prediction of response to therapy. The precise prediction of tumor biological behavior would facilitate treatment selection for patients who may benefit from radical surgical treatment or adjuvant therapy. We provide a current, comprehensive review of the literature on bladder tumor markers with a special emphasis on their prognostic potential. The literature suggests that currently no single marker is able to accurately predict the clinical course of bladder tumors and thus would serve as a reliable prognosticator. A combination of prognostic markers could predict which superficial tumors need an aggressive form of therapy and which invasive tumors require adjuvant therapy. Altogether, the most promising markers are, at this point, Ki-67 and p53 expression as well as matrixmetalloproteinase complex and angiogenesis.

Prognostic factors in transitional cell cancer of the bladder: an emerging role for Bcl-2 and p53

BACKGROUND AND PURPOSE

In a recent study on patients with transitional cell cancer of the bladder treated with curative radiotherapy following TUR-T, we demonstrated that a low apoptotic index and p53 positivity were associated with poor local control. The purpose of this study was to assess the prognostic significance of additional markers implicated in regulation of cell cycle and apoptosis.

PATIENTS AND METHODS

Bcl-2, Bax and p21 positivity were detected immunohistochemically on paraffin-embedded pre-treatment biopsies from 83 patients with invasive transitional cell cancer (TCC) of the bladder, treated with radiotherapy. In addition, markers determined in an earlier analysis, i.e.: p53, apoptotic index, cyclin D1, retinoblastoma protein and Ki-67 were included in the multivariate analysis. A stepwise proportional hazard analysis was performed, adjusting for classic prognostic factors (T-stage, grade, multifocality and macroscopic completeness of the TUR). Positivity was defined as >10% of tumor cells staining positive for Bcl-2, Bax and p21, and >20% for p53.

RESULTS

Bcl-2 positivity was found in 63%, Bax was positive in 52% and p21 in 55% of cases. In the PH analysis Bcl-2 positivity was found to be related to poor local control (36 vs. 72% at 3 years; P=0.003), as well as to shorter disease-specific survival (74 vs. 94% at 3 years; P=0.017). Evidence for an adverse effect of p53 positivity was also found (local control: 32 vs. 69% at 3 years;P=0.037, disease-specific survival: 76 vs. 92% at 3 years; P=0.043). In an additional PH analysis, we found poor local control rates for bladder cancers with combined Bcl-2 and p53 positivity (17 vs. 65% at 3 years; P=0.0017), and lower disease specific survival (60 vs. 92%; P=0.0024), disease-free survival (7 vs.35%, P=0.0023) and overall survival (39 vs. 80%; P=0.0018).

CONCLUSION

This study provides evidence for a poor outcome in patients treated with radiotherapy for TCC of the bladder expressing both Bcl-2 and p53. This relationship was found for local control and disease-free, disease-specific and overall survival.

Mutation of cell cycle regulators and their impact on superficial bladder cancer

Early cytogenetic studies in bladder cancer identify regions of chromosomal gain or loss that can be candidate loci for oncogenes and tumor suppressor genes. Oncogenes with potential prognostic significance identified in bladder cancer the RAS family, epidermal growth factor receptor, ERBB-2, MDM2, and cyclin D1. The TP53 gene has been the most thoroughly characterized tumor suppressor gene in bladder cancer, with correlation of TP53 alterations with type of carcinogenic exposure, tumor stage and grade, as well as prognosis. Studies evaluating alterations of the retinoblastoma pathway have identified the retinoblastoma gene, RB, p161NK4A/CDKN2, and E2F-1 as tumor suppressor genes with potential prognostic significance in patients with bladder cancer. Better understanding of the genetic mechanisms underlying bladder tumor development and progression will allow better prevention, diagnosis, and treatment strategies.

Urological malignancies and the proteomic-genomic interface

The urological malignancies, renal, bladder and prostate cancer, account for approximately 16% of all cancer cases. Unfortunately 5-year survival rates are relatively poor, largely a result of many cases not being diagnosed before the tumour has metastasised. There is a clear need for the identification of markers which will allow earlier detection of disease, and predict prognosis and response to therapy. In addition, they may be of use as therapeutic targets. Current advances in molecular biology are allowing the identification of a number of tumour-associated changes which could be of clinical use in the future. However, with the rapid technological advances being made in the field of proteomics, this approach could be integrated with genomics providing a complementary alternative, overcoming disparities between mRNA levels and protein production, and additionally allowing the identification of tumour-associated post-translational modifications. These approaches have already been used to identify novel genes and other cancer-related changes involved in the pathogenesis of urological malignancies. This review describes current progress in the genomic and proteomic study of urological malignancies, and highlights the potential of using proteomic technologies in the study of this group of diseases.