Expression of cell-cycle regulatory proteins and their prognostic value in superficial low-grade urothelial cell carcinoma of the bladder.

AIMS: Cell-cycle regulatory proteins are important indicators in determining progression trough the cell-cycle and progression to invasive cancer in patients presenting with superficial bladder cancer. We performed an immunohistochemical study in order to evaluate the prognostic value of the expression of p16, p27, pRb, p53 and Ki-67 in superficial grade I and II papillary urothelial cell carcinoma of the bladder. METHODS: p16, p27, p53, pRb and Ki-67 immunoexpression was studied in 14 pTa, 35 pT1a and 7 pT1b bladder tumours at presentation and at recurrence of their tumours. The recurrence-free survival and the progression-free survival were analysed according to these regulatory cell-cycle proteins expression. RESULTS: For survival in univariate analysis a high Ki-67 labelling index was a poor prognostic factor for recurrence-free and progression-free survival (P=0.0014 and P=0.012, respectively). Ki-67 labelling index was also an independent recurrence-free survival prognostic factor (P=0.0005). The p16, p27, p53 and pRb immunoreactivity was not significantly associated with recurrence or progression rate in this group of bladder carcinomas. CONCLUSIONS: These data suggest that the Ki-67 labelling index can be a reliable marker in predicting recurrence and/or progression in superficial low-grade bladder carcinomas and may be relevant in planning adjuvant therapy.     

Predictive value of cell cycle markers p53, MDM2, p21, and Ki-67 in superficial bladder tumor recurrence.

The aim of the study was to determine whether the expression of the cell cycle markers p53, MDM2, p21, and Ki-67 was predictive of superficial bladder cancer recurrence and to compare the relative predictive power for tumor recurrence of a cell cycle index based on the number of abnormally expressed cell cycle markers with a clinicopathological index based on primary clinical tumor characteristics. The expression of p53, MDM2, and p21 proteins and the value of the Ki-67 index were analyzed for 244 patients. One hundred ninety-four lesions were determined to be superficial papillary tumors (pTa), whereas 50 tumors invaded the lamina propria (pT1). Tumor grade was noted low (grade 1) in 83 cases and high (grades 2-3) in 161 cases. An avidin-biotin peroxidase method was performed using monoclonal antibodies against p53, MDM2, p21, and Ki-67 antigens after antigen retrieval treatment of formalin-fixed specimens. The cell cycle marker index was created using the number of abnormally expressed cell cycle markers according to the following cutoff points: p53 (>5%), MDM2 (>20%), p21 (<5%), and Ki-67 (>10%). The clinicopathological index was created using the following adverse tumor characteristics: grades G2-G3, stage pT1, multifocality, and diameter of tumors > 3 cm. Cox regression models were used to calculate the relative risks and their 95% confidence intervals associated with disease recurrence for the clinicopathological index and the cell cycle marker index. The chi2 test was performed to describe the correlation between the Ki-67 index and p53, MDM2, and p21 protein expression. Kaplan-Meier survival curves were generated to demonstrate the disease-free survival according to these two prognostic indexes. The clinicopathological index was a strong, independent predictor of disease recurrence where tumors with three or four adverse tumor characteristics at initial resection had over four times the risk of recurrence than tumors with no risk factors (P for trend = 0.0001). A strong correlation was observed between the Ki-67 index >10% and both MDM2 and p21 proteins. MDM2 was overexpressed in 106 tumors (43%), and p53 was overexpressed in 47 (19%); Ki-67 was >10% in 171 cases (70%). Thirty-nine tumors (16%) were p21 negative. The risk of recurrence increased slightly with the number of abnormally expressed cell cycle markers, but when the clinicopathological index was taken into account in multivariate analysis, the cell cycle marker index was not predictive of disease recurrence (P for trend = 0.72). The cell cycle markers studied provided no added prognostic information on disease recurrence after initial resection of papillary superficial tumors when the clinicopathological parameters were taken into account.     

Biological similarities between murine chemical-induced and natural human bladder carcinogenesis

The present study investigated the similarities between rodent and human urothelial carcinogenesis models using DNA content, p53 and Ki-67 immunoexpression as surrogate markers of bladder carcinogenesis. Following N-butyl-N-(4-hydroxybutyl)-nitrosamine exposure, 49 human cystectomy specimens of bladder cancer and 53 rat bladder specimens were studied. All of the tumours and adjacent mucosa present in each specimen were evaluated. High similarities were observed between the rodent urothelium carcinogenesis process and the corresponding process in humans, in regards to the histopathological features and biological alteration profile: DNA aneuploidy, p53 overexpression and high proliferative index measured by Ki-67 immunoexpression. Despite these similarities, a higher frequency of alterations was observed in earlier stages in the rat chemical-induced carcinogenesis, namely in 5c aneuploid cells, p53 overexpression and higher Ki-67 labelling index. These results confirm that this experimental animal model is a suitable and reproducible model of bladder carcinogenesis, particularly in regards to high-risk non-invasive and invasive urothelial carcinomas. These features mandate its use in the identification of new molecular targets and evaluation of tumour response to new cytotoxic drugs or drug combinations in bladder cancer therapeutic intervention.     

Fibroblast growth factor receptor 3 protein expression in urothelial carcinoma of the urinary bladder, exhibiting no association with low-grade and/or non-invasive lesions

Activating mutations of fibroblast growth factor receptor 3 (FGFR3), found in autosomal dominant human skeletal dysplasia, were reported to be involved in tumorigenesis and correlate with low-grade and superficial lesions of urothelial carcinoma. FGFR3 protein expression was immunohistochemically investigated in 126 cases of urothelial carcinoma of the urinary bladder to evaluate the role of this receptor in tumor behavior. p53 expression and the proliferating activity of tumor cells, assessed by Ki-67 expression, were also analyzed in parallel. Cytoplasmic and/or membrane immunostaining for FGFR3 was observed in 62 (49.2%) cases, including 20 (15.9%) cases of intense staining and 42 (33.3%) of moderate staining. p53 expression and Ki-67 labeling index (LI) were significantly correlated with high tumor grade (p=0.0093 and <0.0001, respectively) and invasion (p=0.0041 and <0.0001, respectively). Although there were two groups of interesting cases: low-grade and non-invasive tumors negative for p53 but positive for FGFR3, and high-grade and invasive tumors positive for p53 but negative for FGFR3, no statistically significant relationship was found between FGFR3 expression and tumor grade, invasion, p53 expression or Ki-67 LI. These results suggest that FGFR3 protein expression in bladder cancer is unlikely to affect tumor behavior as a unique single factor.     

Gene expression profiling of progressive papillary noninvasive carcinomas of the urinary bladder.

PURPOSE: The aim of the present study was to define gene expression profiles of noninvasive and invasive bladder cancer, to identify potential therapeutic or screening targets in bladder cancer, and to define genetic changes relevant for tumor progression of recurrent papillary bladder cancer (pTa). EXPERIMENTAL DESIGN: Overall, 67 bladder neoplasms (46 pTa, 3 pTis, 10 pT1, and 8 pT2) and eight normal bladder specimens were investigated by a combination of laser microdissection and gene expression profiling. Eight of 16 patients with recurrent noninvasive papillary bladder tumors developed carcinoma in situ (pTis) or invasive bladder cancer (> or = pT1G2) in the course of time. RNA expression results of the putative progression marker cathepsin E (CTSE) were confirmed by immunohistochemistry using high-throughput tissue microarray analysis (n = 776). Univariate analysis of factors regarding overall survival, progression-free survival, and recurrence-free survival in patients with urothelial bladder cancer was done. RESULTS: Hierarchical cluster analyses revealed no differences between pTaG1 and pTaG2 tumors. However, distinct groups of invasive cancers with different gene expression profiles in papillary and solid tumors were found. Progression-associated gene profiles could be defined (e.g., FABP4 and CTSE) and were already present in the preceding noninvasive papillary tumors. CTSE expression (P = 0.003) and a high Ki-67 labeling index of at least 5% (P = 0.01) were the only factors that correlated significantly with progression-free survival of pTa tumors in our gene expression approach. CONCLUSIONS: Gene expression profiling revealed novel genes with potential clinical utility to select patients that are more likely to develop aggressive disease.     

Apoptotic and proliferation indexes in primary superficial bladder tumors

Whether apoptotic index [AI] and/or Ki-67 labeling index [Ki-67LI] add prognostic information in bladder cancer remains unclear. Mean AI and Ki-67 LI increased with grade and stage in 147 superficial bladder tumors. AI (>1.7%) correlated with tumor size, grade and proliferation. Ki-67 LI (>10%) correlated with higher grade and stage. Tumor size and Ki-67 LI were independent predictors of disease-free and progression-free survival, respectively. Tumor size, patient's age and tumor's recurrence predicted overall survival. We conclude that conventional clinical parameters and Ki-67 LI define risk groups of bladder tumors, while AI has limited value.     

Motility-related protein 1 (MRP-1/CD9) expression in urothelial bladder carcinoma and its relation to tumor recurrence and progression

BACKGROUND: CD9 has been implicated in cell adhesion, motility, and proliferation, and numerous studies have demonstrated its prognostic value in different solid tumors. The objective of this study was to determine the relation of CD9 expression to tumor grade and tumor stage of urothelial carcinoma of the bladder and to define the value of CD9 in predicting the behavior of superficial papillary tumors (SPTs) (pathologic Ta [pTa] and pT1). METHODS: Three hundred twenty patients (118 patients with pTa tumors, 111 patients with pT1 tumors, and 91 patients with pT2 tumors) were examined for CD9 expression using immunohistochemistry applied on formalin fixed, paraffin embedded tissue. Patients were stratified into 3 categories, depending on CD9 expression: positive (> 50% positive cells), reduced (5-50% positive cells), or negative (< 5% positive cells). RESULTS: Loss of CD9 expression was found to be associated significantly with high-grade and high-stage urothelial tumors (P < 0.0001). A reduced/negative (altered) CD9 expression was associated with SPT progression, but not with recurrence (P < 0.001). Patients who had pTa or pT1 tumors with altered CD9 expression had a relative risk of 5.59 (P = 0.005; 95% confidence interval [95% CI], 1.69-18.48) for progression compared with patients who had tumors with positive CD9 expression. Kaplan-Meier curves showed that a lack of CD9 expression was associated significantly with progression free survival (P < 0.001; log-rank test), but not with recurrence. In patients with SPTs, multivariate Cox proportional hazards regression analysis revealed that negative CD9 expression was an independent prognostic marker for the prediction of tumor progression (P = 0.007; 95% CI, 0.11-0.70). CONCLUSIONS: In patients with urothelial bladder carcinoma, CD9 expression was associated significantly with tumor stage and grade, and a loss of CD9 expression was an independent prognostic factor for predicting progression in patients with SPTs. Thus, CD9 immunoexpression is a potential new predictor of tumor behavior in patients with SPTs of the urinary bladder.     

High-throughput tissue microarray analysis of COX2 expression in urinary bladder cancer

To investigate whether protein expression of cyclooxygenase 2 (COX2) is associated with tumor phenotype, immunohistochemical alterations, and clinical outcome in urinary bladder cancer (BC). Tissue microarrays (n = 776) were used to analyze COX2, P53 and the Ki-67 labeling index immunohistochemically. A monoclonal mouse antibody was used after heat-induced antigen retrieval. COX2 expression was scored semiquantitatively (0-3+). COX2 expression was detected in 60% (368/617) of urothelial BC. Positive COX2 staining was seen in 77.8% (140/182) of muscle invasive urothelial BC, compared to 35% (7/20) of muscle invasive squamous cell carcinomas (p < 0.001). COX2 protein expression was associated with advanced tumor stage (p < 0.0001), high-grade histology (p < 0.0001), solid growth pattern in invasive BC (pT1-4, p = 0.02), high Ki-67 labeling index (p < 0.0001), and positive P53 IHC (p < 0.001). COX2 expression was not associated with survival, recurrence, and progression in clinically relevant subgroups (pTa, pT1, pT2-4). Expression of COX2 is common in advanced BC with poor prognostic characteristics, supporting efforts to initiate clinical trials on the efficacy of COX2 inhibitors in the adjuvant treatment of high-risk urinary BC.     

Prognostic value of p53, p21/WAF1, Bcl-2, Bax, Bak and Ki-67 immunoreactivity in pT1 G3 urothelial bladder carcinomas.

pT1 G3 bladder carcinomas are heterogeneous with respect to tumor recurrence and progression. Whereas some urologists treat these carcinomas by repeated transurethral resections often followed by intravesical chemotherapy or BCG instillation, others recommend cystectomy after tumor recurrence or early cystectomy after the initial diagnosis. Our goal was to determine the prognostic value of p53, p21/WAF1, Bcl-2, Bax, Bak, and Ki-67 immunoreactivity in these tumors. There were 30 patients with a new histopathological diagnosis of pT1 G3 urothelial carcinoma based on a transurethral resection specimen. Representative sections of these specimens were examined for the above markers. All patients were followed up regularly and were classified as being tumor free or having tumor recurrence or progression. The mean follow-up period was 43 months (range: 8-102 months). Twenty-five patients underwent radical cystectomy and 7 of these (28%) suffered from tumor progression and died of bladder cancer. In 5 patients, surgery was limited to a transurethral resection and 4 of these patients developed superficial tumor recurrence. There was a significant difference in tumor-free survival between patients with p53-immunoreactive (mean: 30 months) and p53-negative tumors (mean: 82 months; p = 0.0341). Bcl-2 positivity was also associated with decreased tumor-free survival (p = 0.043). The other markers had no significant prognostic impact. We conclude that p53 and Bcl-2 immunoreactivity labels the most aggressive pT1 G3 bladder carcinomas.     

Ki-67: a prognostic factor for low-grade glioma?

PURPOSE: Immunohistochemical techniques were used to detect the expression of Ki-67, a nuclear proliferation marker, in 180 low-grade glioma tumor specimens to determine whether Ki-67 is a prognostic predictor of survival or tumor recurrence. MATERIALS AND METHODS: A clinical database of 180 low-grade glioma patients (35 children aged /=5%. An average Ki-67 value of >/=5% was prognostically significant for reduced cause-specific survival (CSS, p = 0.05) and a Ki-67 level >/=10% was strongly significant of a poor survival outcome (p = 0.009). Ki-67 was not prognostically significant for progression-free survival. Other prognostically significant factors for CSS included age (p = 0.05), Karnofsky performance status (p = 0.0001), radiation dose (p = 0.02), extent of surgical resection (biopsy vs. others, p = 0.004), and timing of radiation (p = 0.0005). Ki-67 did not remain an independent statistically significant factor for CSS on multivariate analysis. Age and Ki-67 positivity (both maximal and average values) directly correlated (i.e., advancing age was associated with a higher Ki-67 index). When the patient group was further subdivided by age and timing of RT (postoperative vs. deferred), the prognostic significance of Ki-67 for CSS was lost. Within the deferred RT subgroup, a maximal Ki-67 >2% was associated with a worsened CSS. Within the pediatric population, Ki-67-negative patients had a 5-year CSS and progression-free survival of 100%. The 5-year CSS and progression-free survival declined significantly to 84% and 67% for patients with tumors demonstrating any degree of Ki-67 positivity (p = 0.005 and p = 0.006, respectively). CONCLUSION: Ki-67 is a useful predictor of CSS in low-grade gliomas; however, it is not independent of other prognostic factors, particularly age. Although Ki-67 was not helpful in predicting which adult patients were likely to benefit from postoperative RT, the results of the present study indicate a possible utility in the selection of pediatric patients for RT and in the selection of poorer prognosis patients for clinical trials.     

The prognostic value of MDM2 overexpression in superficial urothelial bladder carcinoma

The prognostic significance of p53 accumulation and MDM2 overexpression in superficial and papillary urothelial cell carcinoma (UCC) of the bladder has not yet been established. Therefore, MDM2 and p53 protein were investigated focusing on tumour grade and muscularis mucosae invasion in order to identify their prognostic significance. Thirty-five archival UCC were studied by immunohistochemistry using monoclonal antibodies DO7 against p53, and IB10 against MDM2. MDM2 overexpression was observed in 51.4% of the cases. The recurrence rate for patients with MDM2 overexpression was 7.09 fold higher than for those without MDM2 overexpression. p53 accumulation was not related to prognosis. There was no significant difference between low and high grade tumours in regard to MDM2 overexpression and p53 accumulation. pTa cases presented the higher frequency of MDM2 positive cases (66.7%) and a lower frequency of p53 accumulation (33.3%). MDM2 overexpression does not seem to be related to muscular mucosae invasion. Thus, MDM2 status may well be a prognostic marker in superficial urothelial bladder carcinomas.     

IMP3 predicts aggressive superficial urothelial carcinoma of the bladder

PURPOSE: In this study, we investigated whether an oncofetal protein, IMP3, can serve as a new biomarker to predict progression and metastasis of early-stage urothelial carcinoma of the bladder. EXPERIMENTAL DESIGN: The expression of IMP3 in 242 patients with primary superficial bladder urothelial carcinoma and metastatic urothelial carcinoma was evaluated by immunohistochemistry. Patients with primary superficial urothelial carcinoma of the bladder were further investigated by use of survival analysis. RESULTS: Twenty percent (42 of 214) of primary superficial urothelial carcinomas and 93% (26 of 28) of metastatic urothelial carcinomas expressed IMP3. Kaplan-Meier plots and log-rank tests showed that patients with IMP3-positive tumors had a much lower progression-free survival (P = 0.0002) and disease-free survival rate (P = 0.0067) than did those with IMP3-negative tumors. The 5-year progression-free and disease-free survival rates were 91% and 94% in IMP3-negative patients versus 64% and 76% in IMP3-positive patients, respectively. Sixty percent of IMP3-positive patients with superficial invasive urothelial carcinoma at initial diagnosis went on to develop metastases, whereas no metastasis was found in IMP3-negative patients (P = 0.0017). In the multivariable Cox analysis, patients with IMP3 expression in their superficial urothelial carcinomas subsequently developed invasive tumors or metastasis at a rate that was about five times greater than cases without expression of IMP3 adjusting for other well-known clinical variables (tumor stage and grade, etc.). CONCLUSIONS: Our findings indicate that IMP3 is an independent prognostic marker that can identify a group of patients with a high potential to develop progression and who might benefit from early aggressive therapy.     

MUC1 expression in intramucosal colorectal neoplasms. Possible involvement in histogenesis and progression

PURPOSE: The mucin core peptide MUC1 often is detectable in colorectal carcinoma (CRC) tissue and cell lines. However, whether MUC1 in CRC correlates with tumor histogenesis and progression is unclear. We studied the relationship between MUC1 expression in intramucosal CRC and clinicopathologic features, expression of Ki-67, and p53 protein, and apoptosis. METHODS: The intramucosal CRC we studied included 140 endoscopically or surgically resected lesions, including 106 low-grade carcinomas and 34 high-grade carcinomas. De novo carcinoma, defined as carcinoma with no adenomatous component, represented 9 of 140 tumors. Three macroscopic types were identified: 57 lesions were polypoid, 55 were superficial and flat, and 28 were granular-type laterally spreading tumors (G-LST). MUC1, Ki-67, and p53 expression were examined immunohistochemically. Apoptotic cells were identified by in situ DNA nick end labeling. RESULTS: MUC1 expression in high-grade carcinomas was significantly more frequent (p < 0.01) than in low-grade carcinomas; expression in adenomas was almost nil. MUC1 expression in polypoid carcinomas was significantly more frequent (p < 0.05) than in superficial carcinomas or G-LST. MUC1 expression in carcinomas with p53 expression was significantly more frequent (p < 0.01) than in carcinomas not expressing p53. No significant correlation was found between expression of MUC1 and Ki-67 labeling index. MUC1 was expressed more frequently in carcinomas with relatively high apoptotic index (p < 0.01). MUC1 expression did not differ between de novo carcinomas and those developing from adenomas. CONCLUSIONS: The results suggest that MUC1 is likely to be expressed in the course of colorectal carcinoma development when p53 protein is overexpressed and apoptosis is prominent.     

E-cadherin immunoreactivity correlates with recurrence and progression of minimally invasive transitional cell carcinomas of the urinary bladder

E-cadherin is a transmembrane glycoprotein involved in intercellular adhesion. Abnormal (i.e., lost or decreased) expression of E-cadherin has been linked to invasiveness of many malignant tumors, including bladder carcinomas. To our knowledge, studies analyzing the prognostic impact of E-cadherin immunoreactivity especially in minimally invasive transitional cell bladder carcinomas (stage pT1) have not been published in the Anglo-American literature. In the present study, we immunostained 69 cases of pT1 transitional cell bladder carcinomas for E-cadherin using multitissue arrays. The results were compared with p53 and Ki-67 antigen immunoreactivity, clinicopathological parameters and the patients' outcome. E-cadherin immunoreactivity, which was found abnormal in 42% of cases, correlated significantly with substage (pT1a/pT1b; p=0.029) and p53 index (p=0.041) and tendentiously with Ki-67 antigen index (p=0.089) and age (p=0.07). By univariate Cox regression analysis, abnormal E-cadherin immunostaining correlated significantly (p=0.005) with early tumor recurrence, but not with early tumor progression (p=0.168). In a multivariate analysis, this parameter was identified, besides tumor grade (p=0.002), as an independent predictor of recurrence-free survival (p=0.016). Concerning tumor progression, age was identified as the single independent prognostic parameter (p=0.041), but E-cadherin immunoreactivity displayed a tendentious independent predictive value in this respect (p=0.071). We conclude from our data that immunohistochemical E-cadherin staining may provide additional prognostic information in patients with pT1 bladder carcinomas.     

Investigation of pericytes, hypoxia, and vascularity in bladder tumors: association with clinical outcomes

The contribution of endothelial cell growth to angiogenesis has been widely studied; however, the involvement of pericytes is less well documented, especially in human tumors. In this study we aimed to quantify and assess the prognostic significance of pericyte coverage, the extent of hypoxia, and microvessel density (MVD) in normal bladder mucosa and urothelial carcinoma. Antibody to alpha-smooth muscle actin was used to assess the distribution of pericytes (mural/smooth muscle cells) in the microvessels of normal human bladder (n = 4) mucosa and in urothelial carcinoma (n = 47) samples; this was quantitated using microvessel pericyte index (MPI). The MVD was measured using two different methods (n = 47) and hypoxia was assessed using glucose transporter-1 (Glut-1) staining (n = 30). There was a 70% reduction in MPI in urothelial carcinomas compared to normal bladder mucosa (p < 0.0012); MPI did not correlate with tumor stage or grade. Ta and T1 superficial tumors were divided into two groups with a MPI of <15% or >15%. Progression-free survival was significantly shorter for tumors with MPI >15% (p = 0.0036). MVD had no prognostic value using either evaluation method. Glut-1 immunoreactivity was not prognostic in superficial urothelial carcinoma samples. Tumors with a higher MPI showed a greater Glut-1 immunoreactivity (p = 0.0051). Microvessels in urothelial carcinoma have a considerable loss of pericyte coverage compared to normal bladder mucosa. The data from this preliminary study indicate that progression-free survival was shorter in patients whose superficial tumors had higher pericyte coverage of the microvessels. This may be due to increased levels of hypoxia, as demonstrated by a significant increase in Glut-1 staining.     

TRIO的扩增和高表达与膀胱肿瘤细胞的快速增殖有关

目的TRIO基因位于染色体5p扩增区、编码1种在细胞周期调节中起主导作用的蛋白,本研究旨在了解TRIO的扩增和表达是否与膀胱肿瘤细胞的快速增殖有关。方法Ki67标记染色(Ki67LI)、荧光原位杂交(FISH)和定量PCR法(LightCyclerTMPCR)被用于研究。结果TRIO基因扩增与膀胱肿瘤细胞的快速生长相关(P<0.0001)。膀胱肿瘤分化越差、临床分期越高,Ki67LI与TRIO基因扩增数目均越高。含2317例组织微阵列FISH结果显现TRIO扩增仅见于1.8%早期膀胱肿瘤(pTa)(9例/499例),而在膀胱癌(pT1-4)高达12.8%(62例/485例)。定量PCR法进一步证实TRIO在显示5p扩增的膀胱癌组织高表达。结论TRIO扩增与膀胱肿瘤细胞的快速增殖有关,TRIO扩增和高表达可能在膀胱癌的发展过程中发挥重要作用。     

The abnormalities in the p53/p21WAF1 pathway have a significant role in the pathogenesis and progression of gastrointestinal stromal tumors

To elucidate the prognostic role and relationship of the p53/p21/PCNA pathway in gastrointestinal stromal tumors (GISTs), a total of 167 resected gastric and small intestinal CD117-positive stromal tumor specimens were collected from January 1987 to December 2000. Immunohistochemical studies were performed on the paraffin sections with antibodies of p53, p21/WAF1, proliferating cell nuclear antigen (PCNA) and Ki-67. The immunoreactivity of four markers was recorded by labeling index (LI, %) for clinicopathologic and survival correlation. The labeling index was 0-83% for p53, 0-81% for p21/WAF1, 0-33% for Ki-67 and 12-92% for PCNA. Completely negative immunostaining (LI<1%) was found in 54.5% of p53, 25.8% of p21/WAF1 and 44.3% of Ki-67. The LI of four markers strongly correlate with each other (p<0.05). Furthermore, the LI of all four markers positively correlate to microscopic tumor mitotic counts (p<0.05). Only the LI of p53 and PCNA positively correlate to tumor sizes. Tumors with non-spindle cell type (versus spindle cell) and high cellular pleomorphism (versus low) exhibited a higher p53, p21/WAF1 and PCNA LI (p<0.05). Increased NIH risk significantly correlates to increased p53, PCNA and Ki-67 (p<0.05) LI. Survival analysis indicated that a large tumor size (> or =5 cm, p=0.003), increased tumor mitosis (> or =5/50 HPF, p<0.001), high NIH risk (p<0.001), non-spindle cell type (p=0.024), high p53 LI (p<0.001), high p21/WAF1 LI (p=0.007), high Ki-67 LI (p<0.001) and high PCNA LI (p<0.001) were prognostic factors for poor disease-free survival. Independent factors are tumor size, NIH risk, p53 and p21/WAF1 LI. We demonstrated the first evidence of the linear relationship and prognostic role of the p53/p21/PCNA pathway in gastrointestinal stromal tumors. Abnormalities of the p53/p21WAF1 pathway lead to increased proliferating states, thereby triggering the progression of GISTs.     

The prognostic value of KI-67 proliferation index in transitional cell carcinoma of renal pelvis and ureter

The investigation deals with Ki-67 immunoreactivity assay in upper urinary tract transitional cell carcinoma (TCC) with respect to grade, stage and survival after radical surgery. In a retrospective study (5yrs) of 37 patients with TCC of the renal pelvis and ureter, who had undergone radical nephroureterectomy and bladder resection, pT1-pT4 lesions and G1-G3 tumors were identified. Ki-67 expression was evaluated by immunohistological staining (1:100; MIB-1; Immunotech. Inc., Westbrook, USA). By using fifteen x600 visual fields, Ki-67 labeling index (number of positive cells per 100 tumor cells) was found (mean +SD--29.7 +/- 9.22). There was a correlation between the index and tumor stage (p < 0.001) and grade (p = 0.002). The Ki-67 values in excess of 27 corresponded to high risk of bladder recurrence (p < 0.001) and short duration of recurrence development (p = 0.067) whereas, for the index of under 22, five-year progression-free survival was more frequent (p < 0.001). Having been tested in that study, discriminative modeling yielded the following parameters: sensitivity and specificity for bladder recurrence was 93% and 79% while for 5-year progression-free survival- 89% and 100%.     

p53 immunodetection of liquid-based processed urinary samples helps to identify bladder tumours with a higher risk of progression

p53 could help identify bladder tumour cases with a risk of progression from superficial to invasive disease. Semiautomatic, liquid-based cytology (LBC) techniques offer an opportunity to standardise molecular techniques. The aim of our study was to investigate whether LBC could improve p53 immunolabelling, and to assess whether urinary p53 could have a prognostic value. Immunoreactivity for p53 was studied in 198 urine samples after treatment with the Cytyc Thinprep processor. After antigen retrieval, cells were labelled with a monoclonal antibody that recognises both wild-type and mutant form of the p53 protein (Clone DO-7, Dako), 1/1000. Positivity for p53 was assessed in 17.2% of the cases. High-grade (G3) tumours were positive in 74.1% of the cases. Comparatively, low-grade (G1-2) urothelial carcinomas were positive in 23.5% of the cases. During a median follow-up period of 26 months, recurrence was observed in 52.9% of the cases with p53 overexpression, and in only 10.9% of negative cases (P < 0.001). The progression rate was 35.3% of p53-positive cases vs 5.5% of p53-negative cases (P < 0.001). Progression-free survival was significantly shorter in patients with p53 accumulation (P = 0.007). In a multivariate analysis stratified on grade and stage, p53 was an independent predictor of overall survival (P = 0.042). The results show that using Thinprep LBC, p53 immunolabelling of voided urothelial cells allows most high-grade tumours to be detected and may help identify cases with a higher risk of recurrence and progression.     

Genetic alterations in urothelial bladder carcinoma: an updated review

New oncogenes and tumor suppressor genes that play an important role in the pathogenesis of urothelial bladder carcinoma have been discovered. The objectives of this review were to summarize the most important oncogenes and tumor suppressor genes involved in urothelial carcinoma and to address their role in pathogenesis, their prognostic value, and their potential use as therapeutic targets. The collected data led the authors to propose a common pathway in which the fibroblastic growth factor receptor 3 (FGFR3) mutation seems to be the earliest genetic abnormality responsible for the transformation from normal tissue to atypia and dysplasia. Three different progression pathways were proposed: The first operative pathway is from dysplasia to superficial papillary pathologic Ta (pTa) tumors to pT1 tumors and, ultimately, to pT2 tumors with FGFR3 and tuberous sclerosis complex 1 (TSC1) the responsible genes. The second major operative pathway is from dysplasia, to carcinoma in situ, and to solid pT1 and pT2 tumors. The third pathway of progression is from dysplasia to papillary T1 and pT2 tumors. The genes involved in the last 2 pathways are the p53, serine threonine protein kinase 15 (STK15), triple-function domain (TRIO), fragile histidine triad (FHIT), p63 genes; and alterations of 20q and 5p, alterations of adhesions, angiogenesis, and matrix-remodeling gene products also are involved. Finally, murine leukemia viral oncogene homologue 1 (RAF1) and CD9 are involved in the progression from papillary pT1 tumors to pT2 tumors.