Studies by comparative genomic hybridization revealed that the 19q13 chromosomal region is frequently amplified in bladder cancer. The cyclin E gene (CCNE), coding for a regulatory subunit of cyclin-dependent kinase 2, has been mapped to 19q13. To investigate the role of cyclin E alterations in bladder cancer, a tissue microarray of 2,317 specimens from 1,842 bladder cancer patients was constructed and analyzed for CCNE amplification by fluorescence in situ hybridization and for cyclin-E protein overexpression by immunohistochemistry. Fluorescence in situ hybridization analysis showed amplification in only 30 of the 1,561 evaluable tumors (1.9%). Amplification was significantly associated with stage and grade (P: < 0.0005 each). Immunohistochemically detectable cyclin E expression was strong in 233 (12.4%), weak in 354 (18.9%), and negative in 1, 286 of the 1,873 interpretable tumors. The majority (62.1%) of CCNE-amplified tumors were strongly immunohistochemistry-positive (P: < 0.0001). The frequency of protein expression increased from stage pTa (22.2%) to pT1 (45.5%; P: < 0.0001) but then decreased for stage pT2-4 (29.4%; P: < 0.0001 for pT1 versus pT2-4). Low cyclin E expression was associated with poor overall survival in all patients (P: < 0.0001), but had no prognostic impact independent of stage. It is concluded that cyclin E overexpression is characteristic to a subset of bladder carcinomas, especially at the stage of early invasion. This analysis of the prognostic impact of CCNE gene amplification and protein expression in >1,500 arrayed bladder cancers was accomplished in a period of 2 weeks, illustrating how the tissue microarray technology remarkably facilitates the evaluation of the clinical relevance of molecular alterations in cancer.
The number of genes suggested to play a role in cancer biology is rapidly increasing. To be able to test a large number of molecular parameters in sufficiently large series of primary tumours, a tissue microarray (TMA) approach has been developed where samples from up to 1000 tumours can be simultaneously analysed on one glass slide. Because of the small size of the individual arrayed tissue samples (diameter 0.6 mm), the question arises of whether these specimens are representative of their donor tumours. To investigate how representative are the results obtained on TMAs, a set of 2317 bladder tumours that had been previously analysed for histological grade and Ki67 labelling index (LI) was used to construct four replica TMAs from different areas of each tumour. Clinical follow-up information was available from 1092 patients. The histological grade and the Ki67 LI were determined for every arrayed tumour sample (4x2317 analyses each). Despite discrepancies in individual cases, the grade and Ki67 information obtained on minute arrayed samples were highly similar to the data obtained on large sections (p<0.0001). Most importantly, every individual association between grade or Ki67 LI and tumour stage or prognosis (recurrence, progression, tumour-specific survival) that was observed in large section analysis could be fully reproduced on all four replica TMAs. These results show that intra-tumour heterogeneity does not significantly affect the ability to detect clinico-pathological correlations on TMAs, probably because of the large number of tumours that can be included in TMA studies. TMAs are a powerful tool for rapid identification of the biological or clinical significance of molecular alterations in bladder cancer and other tumour types.
Gene amplification is a common mechanism for oncogene overexpression. High-level amplifications at 11q13 have been repeatedly found in bladder cancer by comparative genomic hybridization (CGH) and other techniques. Putative candidate oncogenes located in this region are CCND1 (PRAD1, bcl-1), EMS1, FGF3 (Int-2), and FGF4 (hst1, hstf1). To evaluate the involvement of these genes in bladder cancer, a tissue microarray (TMA) containing 2317 samples was screened by fluorescence in situ hybridization (FISH). The frequency of gains and amplifications of all genes increased significantly from stage pTa to pT1-4 and from low to high grade. In addition, amplification was associated with patient survival and progression of pT1 tumours. Among 123 tumours with amplifications, 68.3% showed amplification of all four genes; 19.5% amplification of CCND1, FGF4, and FGF3; and 0.8% co-amplification of FGF4, FGF3, and EMS1. Amplification of CCND1 alone was found in 9% of the tumours, while EMS1 alone was amplified in 1.6% and FGF4 in 0.8%. Overall, the amplification frequency decreased with increasing genomic distance from CCND1, suggesting that, among the genes examined, CCND1 is the major target gene in the 11q13 amplicon in bladder cancer.
Gemcitabine in the dose and schedule indicated above has a significant beneficial impact on pain in patients with hormone-refractory prostatic carcinoma despite its limited activity in terms of PSA response and considerable, especially hematological, toxicity.
The objective of the trial is to evaluate the efficacy of capecitabine in patients with metastatic hormone-resistant prostate carcinoma (HRPC), in terms of prostate-specific antigen (PSA) response and clinical benefit (decrease of pain or analgesic score) and its safety profile. In all, 25 patients with HRPC were enrolled on a phase II trial of capecitabine (Xeloda s ) at a dose of 1250 mg m À2 orally twice daily on days 1 -14 every 21 days. The inclusion criteria were PSA serum levels 43 Â upper limit of normal, a WHO performance status 0 -2, age o85 years and adequate bone marrow, liver and renal function. In patients with grade 2 or higher haematological toxicity on day 1 of the treatment cycle, therapy was first delayed, and then continued at a lower dose. Trial end points were PSA response and clinical benefit defined by quality of life (QL) data and analgesic consumption. The median age of patients was 70 years (range 54 -85 years). A median of three cycles of capecitabine was administered (range 1 -8). PSA response was observed in three patients (12%, 95% CI 3 -31%), with times to tumour progression of 18, 21 and 35 weeks, respectively. In these patients, the response durations were 12, 17 and 32 weeks, respectively. Minor PSA regression was also seen in two further patients. The median time to tumour progression of all patients was 12 weeks (95% CI 9 -15 weeks). Haematological toxicity was minor, with leukopenia grade 3 observed in one patient. There were three deaths during trial treatment, respectively, due to sepsis following mucositis and leukopenia, presumed sepsis with mucositis induced by chemotherapy and concomitant radiotherapy and cerebral dysfunction progressing to coma. Hand -foot syndrome grades 2 and 3 were observed in four patients each. Clinical benefit was observed in five patients (20%, CI 7 -41%). Based on toxicity data, we recommend a lower starting dose of 1000 mg m À2 orally twice daily. While capecitabine has some activity in HRPC, as suggested by observed PSA responses, we conclude that it is not worthwhile to investigate capecitabine monotherapy in a phase III trial. Combinations of capecitabine with other agents, such as vinorelbine or docetaxel, may prove to be more effective.
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