Immunohistochemistry of p53 protein in transitional-cell carcinoma of the bladder using an image analyzer

Prognostic impact of p63 and p53 expression in upper urinary tract transitional cell carcinoma

OBJECTIVES

To analyze p63 and p53 immunoreactivity of upper urinary tract transitional cell carcinoma with respect to prognosis. p63 is required for the differentiation of normal urothelium and is expressed in both non-neoplastic urothelium and transitional cell carcinoma of the bladder.

METHODS

A total of 53 upper urinary tract transitional cell carcinoma specimens were investigated immunohistochemically using a tissue microarray technique. p63 and p53 immunoreactivity was analyzed digitally with respect to associations with pT stage and grade and impact on disease-free survival.

RESULTS

p63 expression was detected in 51 (96.2%) of 53 cases. Normal expression (greater than 90% of tumor cell nuclei) was observed in 1 (4.5%) of 22 Stage pT3 compared with 13 (41.9%) of 31 Stage pT1-T2 tumors (P = 0.003) and 4 (16%) of 25 G3 compared with 10 (35.7%) of 28 G2 tumors (P = 0.13). p53 overexpression (more than 10% of tumor cell nuclei) was found in 10 (18.9%) of 53 cases, including 2 (6.5%) of 31 Stage pT1-T2 and 8 (36.4%) of 22 Stage pT3 (P = 0.011) and 0 of 28 G2 and 10 (40%) of 25 G3 tumors (P <0.001). Metastatic disease was observed in 14 (26.4%) of 53 patients, including none of 14 with normal p63 expression compared with 14 (35.9%) of 39 with decreased (less than 90% of tumor cell nuclei) p63 expression (P = 0.02) and 5 (50%) of 10 patients with p53 overexpression compared with 9 (20.9%) of 43 patients with p53-negative tumors (P = 0.01). Multivariate analysis proved Stage pT3 was the only independent prognostic factor.

CONCLUSIONS

Decreased p63 immunoreactivity and p53 overexpression were significantly associated with advanced tumor stages and poor prognosis. However, neither parameter was an independent prognostic factor in multivariate analysis.

Collagen matrix in development and progression of experimentally induced respiratory neoplasms in the hamster

Intratracheal instillations of 7H-dibenzo(c, g)carbazole (DBC), a tobacco smoke component, into Syrian golden hamsters, resulted in preneoplastic lesions and benign and malignant respiratory neoplasms. Neoplastic progression was associated with specific changes in the extracellular matrix (ECM), dependent on the stage of tumor development. DBC-induced tracheobronchial squamous metaplasia was associated with an increase in collagen type I and type III deposition in the subepithelial ECM, as observed by computer-assisted image analysis of immunohistochemical staining for the aminoterminal propeptides of collagen type I (PINP) and collagen type III (PIIINP). Increased collagen matrix synthesis was detected in dysplasia by in situ hybridization of alpha1(I) mRNA for collagen I and alpha1(III) mRNA for collagen type III after continued exposure to DBC. In well-differentiated squamous cell carcinomas with an expansive growth pattern, collagen deposition increased, as did fiber size. In moderately differentiated neoplasms, basement membrane (BM) destruction and invasion was associated with a destructive growth pattern and decreases in collagen synthesis and the deposition of new collagen. Preserved deposition of mature collagen was detected by staining for the telopeptide of collagen type I propeptide. In less differentiated tumors, ECM development was minimal, with few and small fibers, possibly explaining the rapid development of these neoplasms. Transforming growth factor beta (TGFbeta1) immunoreactivity was increased in hyperplastic epithelium and well differentiated neoplasms and decreased in dysplasia and less differentiated squamous cell carcinomas, while TGFbeta2 and TGFbeta3 expression was also distinct in neoplastic cells. Collagen synthesis and epithelial differentiation were associated with an increased number of myofibroblasts in the ECM and with increased TGFbeta3 immunoreactivity in differentiated cells and in the matrix. The nature of the composition of the ECM was related to neoplastic growth and progression when analyzed by computer-associated image analysis, revealing alterations in collagen structure, size, and shape.

p53 gene transfer to the injured rat carotid artery decreases neointimal formation

PURPOSE

We studied the effect of adenovirus-mediated p53 gene transfer on the injured rat carotid artery to determine its ability to decrease the formation of neointima.

METHODS

In vivo gene transfer was used in isolated segments of balloon-injured rat carotid arteries. Genetically modified adenovirus containing the gene encoding for wild-type p53 (AdWTp53) was applied in three concentrations: 8 x 10(10), 1.6 x 10(10), and 8 x 10(9) pfu/mL. Control rats received either adenovirus null (AdNull), 8 x 10(10) pfu/mL, or Medium-199 solution (vehicle). Expression of p53 was determined 4 days after gene transfer by Western blotting. Neointimal formation was assessed after 14 days by harvesting carotid arteries and determining the intima/media (I/M) ratio based on cross-sectional area measurement. Simultaneously, immunohistochemistry was done to detect the presence of p53 on smooth muscle cell nuclei.

RESULTS

P53 expression was confirmed by Western blotting. There was a significant reduction in neointimal formation on all treated animals compared with controls. The highest dose of AdWTp53 (8 x 10(10) pfu/mL) resulted in a near-total arrest of neointimal formation (I/M = 0.09 +/- 0.03, mean +/- SEM) with P <. 0001 versus vehicle (I/M = 2.23 +/- 0.15) or AdNull (I/M = 2.12 +/-. 12). The intermediate dose of AdWTp53 (1.6 x 10(10) pfu/mL) resulted in an I/M value of 1.04 +/- 0.18, with P <.001 versus vehicle and P =.001 versus AdNull. The lowest dose (8 x 10(9) pfu/mL) resulted in an I/M value of 1.12 +/- 0.18, with P <.001 versus vehicle and P <. 002 versus AdNull. The immunohistochemistry was positive for the presence of p53 in rats infected with AdWTp53.

CONCLUSIONS

Adenovirus-mediated gene transfer of p53 protein significantly decreases the formation of neointima in the rat carotid injury model. This may represent a potential therapy for restenosis in humans.

Bladder tumor markers: need, nature and application. 1. Nucleus-based markers

Urothelial tumors are common: their diagnosis and long-term management represent a large part of most urologists' workload. The majority of such tumors are 'superficial' and are mostly managed by repeated cystoscopic surveillance and treatment. A smaller but significant group of patients either start with, or subsequently progress to, more invasive disease, thus requiring an alternative and more invasive treatment. Maximizing the benefit/risk ratio of the diagnosis and the various treatment options of bladder tumors requires the availability of a reliable tumor marker. The concept of tumor markers encompasses the utilization of any detectable deviation from normality that is indicative of neoplasia. For bladder cancer, most of these markers are present in urine. In this part of the review we examine, from the clinician's point of view, the literature verdict on older techniques such as cytology and cytometry, as well as the current status of new nucleus-based tests such as P53, telomerase, NMP22 and Ki67.