Rolf Ackermann

High frequency of alterations in DNA methylation in adenocarcinoma of the prostate

Alterations of DNA methylation have been reported in many human cancers. In prostatic carcinoma, hypermethylation of the GST P gene promoter and an overall decrease in methylcytosine content have been reported. The aim of the present study was to investigate the frequency and extent of these alterations in relation to tumor stage and grade, in order to explore their clinical relevance and to determine their relationship to each other.

Expression of the c-kit Proto-Oncogene and Its Ligand Stem Cell Factor (SCF) in Normal and Malignant Human Testicular Tissue

Recent findings suggest an important role of the proto-oncogene c-kit, a surface membrane receptor of the tyrosine kinase family, and its ligand stem cell factor (SCF) in normal spermatogenesis and possibly in the pathogenesis of certain testicular germ cell tumors. To further investigate this potential role, the expression of c-kit and SCF was studied in normal and malignant human testicular tissue specimens at the mRNA and protein level by Northern blot analysis and immunohistochemistry, respectively. The detection of the c-kit receptor in normal human germ cells and its natural ligand SCF in Sertoli cells suggests the presence of a local trophic regulatory system that may be active in human spermatogenesis. Additionally, c-kit expression was detected in the seminoma but not in the nonseminoma subtype of human testicular germ cell tumors (GCT). Stem cell factor was not expressed at the mRNA level in tissue from either subtype of GCT as determined by Northern blot analysis; however, the protein was detected immunohistochemically in the cytoplasm of rare tumor cells.

Staging of Pelvic Lymph Nodes in Neoplasms of the Bladder and Prostate by Positron Emission Tomography with 2-[18F]-2-Deoxy-D-Glucose

Objectives: The aim of this study was to evaluate whether pelvic lymph node metastases in patients with neoplasms of the bladder or prostate can be detected applying positron emission tomography with 2-[18F]-2-deoxy-D-glucose (FDG-PET). Methods: Eight patients with bladder cancer and 17 patients with prostate cancer were examined with FDG–PET before pelvic lymph node dissection. Results of PET were then compared to histology of pelvic lymph nodes obtained at surgery. Results: Lymph node metastases were detected by histopathological examination in 3 patients with bladder cancer and in 6 patients with prostate cancer. At the sites with histologically proven metastases, increased FDG uptake suspicious of metastatic disease was found in 2/3 and 4/6 patients, respectively. The smallest detected metastasis was a micrometastasis with a diameter of 0.9 cm. In 3 additional patients who all had histopathologically proven micrometastases (∅ ≤0.5 cm), FDG uptake was within the normal range. No false-positive results were obtained. Conclusions: These results suggest that FDG-PET may be a valuable diagnostic tool in the staging of pelvic lymph nodes in bladder and prostate cancer.

Identifying superficial, muscle-invasive, and metastasizing transitional cell carcinoma of the bladder: Use of cDNA array analysis of gene expression profiles

Purpose: Expression profiling by DNA microarray technology permits the identification of genes underlying clinical heterogeneity of bladder cancer and which might contribute to disease progression, thereby improving assessment of treatment and prediction of patient outcome. Experimental Design: Invasive (20) and superficial (22) human bladder tumors from 34 patients with known outcome regarding disease recurrence and progression were analyzed by filter-based cDNA arrays (Atlas Human Cancer 1.2; BD Biosciences Clontech) containing 1185 genes. For 9 genes, array data were confirmed using real-time reverse transcription-PCR. Additionally, Atlas array data were validated using Affymetrix GeneChip oligonucleotide arrays with 22,283 human gene fragments and expressed sequence tags sequences in a subset of three superficial and six invasive bladder tumors. Results: A two-way clustering algorithm using different subsets of gene expression data, including a subset of 41 genes validated by the oligonucleotide array (Affymetrix), classified tumor samples according to clinical outcome as superficial, invasive, or metastasizing. Furthermore, (a) a clonal origin of superficial tumors, (b) highly similar gene expression patterns in different areas of invasive tumors, and (c) an invasive-like pattern was observed in bladder mucosas derived from patients with locally advanced disease. Several gene clusters that characterized invasive or superficial tumors were identified. In superficial bladder tumors, increased mRNA levels of genes encoding transcription factors, molecules involved in protein synthesis and metabolism, and some proteins involved into cell cycle progression and differentiation were observed, whereas transcripts for immune, extracellular matrix, adhesion, peritumoral stroma and muscle tissue components, proliferation, and cell cycle controllers were up-regulated in invasive tumors. Conclusions: Gene expression profiling of human bladder cancers provides insight into the biology of bladder cancer progression and identifies patients with distinct clinical phenotypes.

Glutathione transferase isozyme genotypes in patients with prostate and bladder carcinoma.

Abstract. Genotype distributions for GSTP1, GSTM1, and GSTT1 were determined in 91 patients with prostatic carcinoma and 135 patients with bladder carcinoma and compared with those in 127 abdominal surgery patients without malignancies. None of the genotypes differed significantly with respect to age or sex among controls or cancer patients. In the group of prostatic carcinoma patients, GSTT1 null allele homozygotes were more prevalent (25% in carcinoma patients vs 13% in controls, Fisher P=0.02, χ2P=0.02, OR=2.31, CI=1.17–4.59) and the combined M1-/T1-null genotype was also more frequent (9% vs 3%, χ2P=0.02, Fisher P=0.03). Homozygosity for the GSTM1 null allele was more frequent among bladder carcinoma patients (59% in bladder carcinoma patients vs 45% in controls, Fisher P=0.03, χ2P=0.02, OR=1.76, CI=1.08–2.88). In contrast to a previous report, no significant increase in the frequency of the GSTP1b allele was found in the tumor patients. Except for the combined GSTM1-/T1-null genotype in prostatic carcinoma, none of the combined genotypes showed a significant association with either of the cancers. These findings suggest that specific single polymorphic GST genes, that is GSTM1 in the case of bladder cancer and GSTT1 in the case of prostatic carcinoma, are most relevant for the development of these urological malignancies among the general population in Central Europe.

Fibroblast growth factors and their receptors in urological cancers: Basic research and clinical implications

Because therapeutical options for advanced urological cancers are limited, the understanding of key elements responsible for invasion and metastasis is very important. It has been hypothesized that progression to malignant growth is associated with a dysregulation of growth factors and/or their receptors. In the last few years, signaling pathways of the fibroblast growth factor (FGF) family have been subject to intense investigation. Fibroblast growth factors constitute one of the largest families of growth and differentiation factors for cells of mesodermal and neuroectodermal origin. The family comprises two prototypic members, acidic FGF (aFGF) and the basic FGF (bFGF), as well as 21 additionally related polypeptide growth factors that have been identified to date. FGFs are involved in many biological processes during embryonic development, wound healing, hematopoesis, and angiogenesis. In prostate, bladder, and renal cancers, FGFs regulate the induction of metalloproteinases (MMP) that degrade extracellular matrix proteins, thus facilitating tumor metastasis. Probably due to their potent angiogenic properties, aFGF and bFGF have received the most attention. However, there is increasing evidence that other FGFs also play crucial roles in tumors of the prostate, bladder, kidney, and testis. This review will discuss the different elements involved in FGF signaling and summarize the present knowledge of their biological and clinical relevance in urological cancers.

Clinical-scale Generation of Dendritic Cells in a Closed System

Immunotherapy of malignant diseases based on dendritic cells (DCs) pulsed with tumor antigens is a promising approach. Therefore, there is a demand for large-scale, clinical-grade ex vivo generation of DCs. Here, a procedure is presented that combines monocyte selection and tissue culture in closed systems under current good manufacturing practice conditions. Leukocytes from three patients with urologic cancers were collected by leukapheresis and subjected to immunomagnetic enrichment. From leukapheresis products containing 1.6 ± 0.2 × 1010 (mean ± SEM) leukocytes with a frequency of CD14+ monocytes of 18.7 ± 2.3%, monocytes were enriched to 94.3 ± 2.2%. CD14+ cell recovery was 67.0 ± 4.7%. After 6 days of culture in Teflon bags in X-Vivo 15 medium supplemented with autologous plasma, GM-CSF, and IL-4, cells showed an immature DC phenotype and efficient antigen uptake. Following an additional 3 days of culture in the presence of GM-CSF, IL-4, IL-1&bgr;, IL-6, TNF&agr;, and PGE2, cells (82.0 ± 5.8% CD83+) displayed a mature DC morphology and phenotype, including expression of CD11b, CD11c, CD18, CD25, CD40, CD54, CD58, CD80, CD86, HLA class I, and HLA-DR as well as expression of CCR7 but not CCR5. The mature DC phenotype remained stable for at least 5 days in the absence of cytokines. Yield of DC was 14.0 ± 4.7% and viability was 91.9 ± 3.5%. Mature DCs effectively clustered with naive T cells and potently induced allogeneic T-cell proliferation and IL-2 and IFN&ggr; but not IL-4 production. Thus, this procedure allows large-scale generation of stably mature, Th1 responses inducing DCs under cGMP conditions in a closed system from cancer patients and is therefore well suited for immunotherapy.

Clinical Outcome of Patients with Lymph Node Positive Prostate Cancer after Radical Prostatectomy versus Androgen Deprivation

OBJECTIVE(S) To compare the outcome of patients with stage D1 (TxN+M0) prostate cancer undergoing radical prostatectomy or androgen deprivation alone. PATIENTS AND METHODS Eighty-two patients treated for lymph node positive prostate cancer were retrospectively analyzed for time to progression, tumor-specific and overall survival. Furthermore, subsequent tumor and treatment related morbidity requiring intervention including frequency and duration of associated hospital stays was recorded. RESULTS The extent of lymph node metastasis was significantly lower in 50 patients undergoing radical prostatectomy (+/- early androgen deprivation) compared to 32 receiving androgen deprivation only. The treatment groups, however, did not differ with regard to other characteristics including age, comorbidity, stage, grade and preoperative PSA. Mean actuarial progression-free, and tumor-specific survival was significantly longer for the radical prostatectomy patients (36% and 47%, respectively at 10 years) compared to androgen deprivation (15% and 32%, respectively). The latter group required more secondary interventions resulting in more frequent and overall longer hospital stays. CONCLUSIONS Patients undergoing radical prostatectomy for stage D1 prostate cancer possibly benefit with regard to the necessity for secondary interventions and, at least for limited (solitary) nodal disease, in terms of progression-free and tumor-specific survival. However, the latter observation may be biased by a larger extent of lymph node metastasis in the androgen deprivation group.

Urological Treatment and Clinical Course of BK Polyomavirus-Associated Hemorrhagic Cystitis in Children after Bone Marrow Transplantation

Hemorrhagic cystitis (HC) is a major complication of bone marrow transplantation (BMT). We describe the clinical course and urological management of BK polyomavirus-associated HC in children after bone marrow transplantation. From 8/88 to 11/95, a total of 117 consecutive pediatric patients received BMT. Nine patients (7.7%) developed HC after transplantation. HC in all 9 patients was characterized by late onset (day +24 to +50 post-BMT), long duration (1–7 weeks) and the excretion of BK polyomavirus in the urine as confirmed by electron microscopy, DNA hybridization and PCR techniques. Six children developed mild HC (grade 1–2) and were treated successfully by hyperhydration. In 3 patients, severe HC (grade 3–4) over 6 weeks required surgical interventions. In these 3 patients, cystoscopy revealed circumscript papulous tumors as the source of hematuria. Severe and persistent hematuria required blood transfusions, insertation of large suprapubic catheters and permanent bladder irrigation because of recurrent blood clot retention. Attempts to stop the hematuria in 2 of these patients by coagulation and laser vaporization (Nd:YAG) failed to stop the bleeding. Differential diagnosis of hematuria after BMT includes urinary tract infection, cyclophosphamide-induced chemical cystitis and bleeding due to BMT-induced thrombocytopenia. With the increasing number of BMTs in children, urologists may be confronted with BK polyomavirus-associated HC and must consider this in the differential diagnosis of hematuria after BMT.

Classic and modern prognostic indicators in renal cell carcinoma. Review of the literature.

The value of classic and modern prognostic factors in renal cell carcinoma as reported in the literature is determined in a review. Tumor stage is the most important single independent prognostic factor. The presence or absence of distant metastases is highly prognostic and presence of lymph node metastases is of higher prognostic value than the presence of renal vein invasion. For each given tumor stage tumor grade (especially nuclear grade) is the most reliable additional independent prognostic factor predicting patient survival. The significance of DNA cytometry as an independent prognostic factor is less clear, though it might be useful in combination with nuclear grading. Patient-related potential prognostic factors such as age, sex and serologic parameters are of lesser, if any, importance. In the future, data from molecular analysis on oncogenes and suppressor genes are likely to provide additional prognostic information.