Hsa-mir-124-3 CpG island methylation is associated with advanced tumours and disease recurrence of patients with clear cell renal cell carcinoma.

BACKGROUND: Whether methylation of the microRNA (mir)-124-3 CpG island is of relevance for the clinical course of a solid cancer and whether it shows association with clinicopathology or survival of patients with renal cell cancer (RCC) is not known as yet. METHODS: In a cross-sectional study, relative methylation of mir-124-3 was measured in 111 RCC samples and 77 paired normal appearing tissues using quantitative methyl-specific PCR. Results were statistically compared with tumour histology, clinicopathological parameters and disease recurrence. RESULTS: We found tumour-specific hypermethylation of mir-124-3 in samples of RCCs with clear cell histology (ccRCC) compared with paired normal appearing tissues (P<0.0001). Methylation was significantly increased in tumours with state of advanced disease (P<0.0001). Higher relative methylation was associated with worse recurrence-free survival in both univariate (hazard ratio=9.37; P=0.0005) as well as bivariate Cox regression analyses considering age, sex, diameter of tumours and state of advanced disease, metastasis and lymph node metastases as covariates (hazard ratios=5.9-18.2; P-values of 0.0003-0.008). CONCLUSION: We identified mir-124-3 CpG islands (CGI) methylation as a relevant epigenetic mark for ccRCC thus underlining the need for functional studies of potentially affected signalling pathways in kidney tumour models. Methylation of mir-124-3 is suggested as an independent prognosticator for ccRCC.

[Expression of corticotropin releasing factor receptor 2 (CRFR2) in the human prostate. A new potential target for medical therapy of benign prostatic hyperplasia]. / Expression des "Corticotropin releasing faktor rezeptors 2" (CRFR2) in der humanen Prostata. Ein möglicher Ansatzpunkt bei der Therapie der benignen Prostatahyperplasie.

BACKGROUND: Expression of urocortin (Ucn), a 40-amino-acid neuropeptide, was demonstrated in the prostatic tissue of patients with benign prostatic hyperplasia (BPH). Ucn showed a significant role in the regulation of local inflammation, proliferation, and relaxation of smooth muscle tone in different organs through activation of corticotropin releasing factor receptor 2 (CRFR2). However, CRFR2 expression in human benign prostatic tissue remains unknown. Our study therefore aimed to investigate CRFR2 expression in prostatic tissue. METHODS: CRFR2 expression was evaluated in tissue samples of human prostate (n=8) by means of reverse transcription polymerase chain reaction (RT-PCR) and immunohistochemistry. RESULTS: mRNA of CRFR2 was abundantly present in RT-PCR of prostate lysates. Immunohistochemistry revealed CRFR2 expression in the cytoplasm of basal and luminal epithelial cells as well as in cystic glands. Smooth muscle components of the stroma and vascular endothelial cells also showed extensive staining for CRFR2. CONCLUSIONS: Our study showed for the first time that human prostatic tissue expresses CRFR2. Pharmacological CRFR2 modulation might be a potential medical treatment for clinical BPH.

[Methylation of the RASSF1A tumor suppressor gene promoter. Risk factor for carcinogenesis of urological tumors]. / Die Methylierung des RASSF1A-Tumorsuppressorgenpromotors. Risikofaktor für die Karzinogenese urologischer Tumoren.

Molecular targets of known risk factors for the development of urological tumors, such as age, smoking, and adiposity, have not yet been elucidated. Hypermethylation of CpG islands in promoters can lead to silencing of gene expression and has frequently been detected in tumors. Age-dependent accumulation of methylation of gene promoters has been observed in various normal tissues and is discussed as a common risk factor for carcinogenesis.Here we describe the RASSF1A tumor suppressor gene as exhibiting an age-dependent promoter methylation in normal kidney tissue, which is additionally affected by the risk factors of anthracosis and adiposity. Furthermore, we found significantly increased methylation of the RASSF1A promoter when comparing peripheral versus central zone prostatic tissue samples.Preliminary expression analysis indicates that RASSF1A could be involved in early tumorigenesis. Our results support the hypothesis that age and other lifestyle-dependent factors may influence promoter methylation of specific genes, possibly serving as future individual tumor risk markers.

Heterogeneous p27(Kip1) expression within primary renal cell cancers, their invasive margins and peritumoral renal parenchyma correlation with pathological and prognostic features.

INTRODUCTION: The expression of the negative cell cycle regulator p27(Kip1) is frequently found to be deregulated in various human cancer types. Whether expression of p27(Kip1) can be used as prognostically relevant biological variables for renal cell cancer patients still remains to be clarified. Therefore, in the present investigation the expression within different tissue areas obtained from renal cell carcinomas was determined. PATIENTS AND METHODS: For analysis of p27(Kip1) in 420 tumor nephrectomy specimens obtained from 420 consecutively included patients, tissue microarrays were used comprising of 1,260 tissue samples each obtained from the tumor itself, the invasive front as well as non-malignant surrounding parenchyma. A sufficient follow-up after surgical therapy was available in 251 cases. RESULTS: In univariate survival analysis, decreased expression of p27(Kip1) within tissue cores obtained from the invasion front was significantly correlated with the patients' disease-specific long-term survival (p = 0.02, log-rank test). In contrast, expression of p27(Kip1) protein within the primary tumors was not identified to reveal any prognostically important information. In Cox regression analysis, histological stage and grade (p < 0.01), the presence of regional lymph node (p < 0.01) or distant metastases at the time of surgery (p < 0.01) as well as decreased expression of p27(Kip1) (p = 0.04) within the invasion front tissue samples independently predicted the disease-specific long-term survival following surgery. CONCLUSION: Our analysis demonstrated that p27(Kip1) is heterogeneously expressed in renal cell carcinomas. Moreover, the result of the present study supports the prognostic value of p27(Kip1) protein expression for patients diagnosed with renal cell carcinoma.

Increased levels of human papillomavirus type 16 DNA in a subset of prostate cancers.

Whether oncogenic human papilloma viruses (HPVs) are involved in the pathogenesis of prostate cancers has been a subject of great controversy. To clarify the contradictory results of investigations, with the aim of detecting viral nucleic acids in prostate cancers, we have carried out a comparative quantitation of the HPV16-E6 sequence in 84 prostate specimens. Using single-tube quantitative competitive PCR, we characterized 47 prostate cancers and 37 control tissues of benign prostatic hyperplasia. A subgroup of the prostate tumors (10 of 47; 21%) was detected as having significantly higher copy numbers of HPV16-E6 sequences when compared to the control tissue (1 of 37; 3%), using a cutoff value of 300 copies per 12,500 diploid cells (two-sided Fisher's exact test, P = 0.02). Our results indicate that the oncogenic HPV16 might contribute to the development of a subset of prostate tumors.

Correlation of bFGF expression in renal cell cancer with clinical and histopathological features by tissue microarray analysis and measurement of serum levels.

The prognostic value of bFGF for surgically treated renal cell cancer (RCC) patients was evaluated by immunohistochemistry (IHC) and the tissue microarray technique (TMA). Additionally, preoperative serum bFGF levels were correlated to tumour stage and the presence of metastases at initial diagnosis. Serum levels of bFGF were measured by ELISA in 39 healthy volunteers, in 37 patients with benign urologic diseases and in 74 RCC patients, 26 of whom revealed lymph node or distant metastases. bFGF expression as detected by IHC was investigated in 777 tissue cores from 259 different RCC patients [median follow-up: 138 (36-240) months]. Eighty eight patients died from tumour progression. For each patient, the TMA slides contained a tissue core from the primary tumour, its invasion front and the normal renal parenchyma. bFGF serum levels were higher in RCC patients vs healthy volunteers (P<0.01) and vs patients with benign urologic diseases (P<0.01). Metastasized patients revealed higher bFGF serum levels than organ-confined specimens (P<0.01). As detected by IHC only increased bFGF expression in the invasion front tissue correlated with the patients' long-term survival (log rank test) (P=0.03). In multivariate analysis regional LN metastases (P<0.01), the histological grading (P<0.01), and an increased bFGF expression in the invasion front (P=0.04) independently predicted the patients' clinical prognosis. Not the expression of bFGF in the primary tumour but in its invasion front reflects the aggressiveness of RCC, hereby indicating a different biological potential within both areas. The value of bFGF serum levels as indicators of systemic tumour dissemination remains to be determined.

[Implications of TCGA Network Data on 2nd Generation Immunotherapy Concepts Based on PD-L1 and PD-1 Target Structures]. / Implikationen der TCGA Netzwerkdaten für Zweit-Generations-Immuntherapiekonzepte auf Basis der PD-L1 und PD-1 Zielstrukturen.

The era of cytokines, given to patients with metastatic renal cell carcinoma (mRCC) as part of an unspecific immunomodulatory treatment concept, seems to have ended with the introduction of targeted therapies. However, preliminary data from studies on treatment with checkpoint inhibitors (e. g. anti-PD-1 and anti-PD-L1) may point the way to second-generation immunotherapy. The rationale of such immunomodulatory treatment is to stop or interrupt the tumour from "escaping" the body's immune defence. Thompson et al. report that increased protein expression of PD-L1 (CD274/ B7-H1) in tumour cells and tumour-infiltrating immune cells (TILs; lymphocytes and histiocytes) is associated with unfavourable clinical pathological parameters as well as poor survival. In small pilot groups of mRCC patients it was found that increased PD-L1 protein expression in tumours and TILs may be correlated with the objective response to anti-PD-1 treatment. Sometimes, however, a very wide variety of response rates was observed, which raises the question if this can be explained by individual expression levels of PD-L1 (CD 274) or PD-1 (PDCD1).Recently published data from the Cancer Genome Atlas (TCGA) Kidney Renal Clear Cell Carcinoma (KIRC) Network now provide a genome-wide data base that allows us to review or validate the molecular results obtained in clear cell renal cell carcinomas (ccRCC) to date.In this study, we analysed the TCGA KIRC mRNA expression data for PD-L1 and PD-1 for a possible association with clinical pathological parameters and the survival of 417 ccRCC patients.The mRNA expression of PD-L1 in primary nephrectomy specimens revealed no significant association with unfavourable clinical parameters. Interestingly, though, a positive correlation with patient survival was found (HR=0,59, p=0,006).These results, which partly contradict the concept applied to date, point out the necessity to ascertain the characteristics of PD-L1 and PD-1 expression at mRNA and protein level in an appropriately sized patient population and evaluate the clinical significance.

The prognostic value of p53 for long-term and recurrence-free survival following radical prostatectomy.

In the present study, 76 specimens (T1-T4) from 76 randomly selected patients undergoing radical prostatectomy at Hannover University as well as in the Josef Hospital Regensburg (13 patients) between 1980 and 1992 for whom tissue sections for immunohistochemical investigation were available, were investigated for different biological and clinical characteristics as predictors for long-term and recurrence-free survival: age, depth of tumour infiltration, histological grade, lymph node status, as well as overexpression of the p53 protein (monoclonal antibody DO-1). After a median follow-up of 50 months, 6 of 18 patients (33%) with more than 20% of tumour cells stained positively for p53 died from tumour progression compared with 9 of 58 patients (16%) with less than 20% of tumour cells positive for p53. During univariate analysis, p53 overexpression (P = 0.011), histological grading (P = 0.009) and tumour stage (P = 0.024) were significant prognostic factors for survival, among which only p53 overexpression (P = 0.026) remained an independent significant predictor in multivariate analysis. Additionally, 18 of 66 patients (27%) with less than 40% positivity for p53 suffered tumour recurrence in contrast to 6 of 10 patients (60%) with more than 40% tumour cells exhibiting a positive staining reaction. In multivariate analysis, p53 overexpression was identified as the only prognostic parameter for recurrence-free survival (P = 0.005). Prospective studies are needed to confirm the independent prognostic potential of p53 overexpression in patients with localised prostate cancer. The availability of more refined prognostic factors should assist decision making regarding the value of radical prostatectomy versus a surveillance strategy for prognostically defined subgroups of patients.

p53 overexpression as a prognostic factor for advanced stage bladder cancer.

Overexpression of the TP53 gene protein detected by immunohistochemistry appears to identify those patients with superficial bladder cancer at risk of the development of muscle invasive or metastatic disease. However, the role of p53 overexpression in patients with advanced or metastatic bladder cancer is not yet well established. In the present study, 44 specimens from 44 patients with advanced stage bladder tumours (T2-T4) undergoing radical cystectomy were investigated for different biological and clinical characteristics as possible prognostic factors: sex, age, depth of tumour infiltration, T-stage, histological grade, lymph node status, application of adjuvant systemic chemotherapy (MVAC), proliferative activity (staining for proliferating cell nuclear antigen (PCNA) by monoclonal antibody (PC10) as well as overexpression of the p53 oncoprotein (monoclonal antibody pAb 1801)). After a median follow-up of 22 months, 16 of the 23 patients (70%) with more than 40% of tumour cells stained positively for p53 (Group B) died from tumour progression compared with 7 of the 21 patients (33%) with less than 40% of tumour cells positive for p53. During univariate analysis, p53 overexpression (P = 0.008), staining for PCNA (> or = 80% of cells positive) (P = 0.01) and tumour stage (P = 0.01) were significant prognostic factors for survival, among which p53 overexpression (P = 0.023) as well as T-stage (P = 0.012) remained independent significant predictors during multivariate analysis. Prospective studies are needed to confirm the independent prognostic potential of p53 overexpression in patients with advanced bladder cancer. The availability of more refined prognostic factors should assist decision making regarding the value of more aggressive treatment options, such as adjuvant or neoadjuvant chemotherapy, for prognostically defined subgroups of patients.

Semiautomated quantitative detection of loss of heterozygosity in the tumor suppressor gene p53.

The most frequently altered gene in diverse tumor types is the tumor suppressor gene p53. Typically, normal function is inactivated by point mutation of one allele and deletion of the other. Therefore, loss of heterozygosity (LOH) of intragenic polymorphic markers is a strong indication for p53 involvement in a cancerous lesion. This study shows that a highly polymorphic short tandem repeat (STR) within intron 1 of p53 is an excellent marker for quantitative evaluation of LOH in tumor samples, whose multicolor, fluorescently tagged PCR products are analyzed and quantitated on an automated DNA sequencer. The range of error was analyzed in detail. Discrete allelic profiles were obtained following amplification of DNA from microdissected cell samples of patients with urogenital tumors. By calculating qLOH, the relative allele ratio of a tumor compared with healthy tissue, a quantitative expression for the LOH is obtained. PCR-based tumor DNA typing using fluorescent STR primers and automated analysis provides an enhanced level of accuracy and sensitivity required for routine analysis in clinical practice, where large numbers of tumor samples have to be processed.

Expression of stem-cell factor and its receptor c-kit protein in normal testicular tissue and malignant germ-cell tumours.

The proto-oncogene c-kit and its ligand stem-cell factor (SCF) may play an important role in the development of normal and malignant testicular tissue. This study investigates the presence of SCF and c-kit protein in 32 orchiectomy specimens of patients with testicular cancer, in 5 specimens of normal testicular tissue and in three established non-seminomatous germ-cell cancer cell lines (H12.1, H32, 577ML) by an immunohistochemical approach. Out of 9 testicular cancer specimens classified as pure seminomas, 7 (78%) showed a strong immunohistochemical reaction for both SCF and c-kit protein on the surface of the tumour cells. Fourteen non-seminomatous germ-cell tumours composed of embryonal carcinoma were completely negative for both SCF and c-kit proteins and only faint positivity was found in 6 tumours (26%). Differentiated teratomatous structures within the specimens on non-seminomatous tumours showed a strong immunohistochemical reaction for SCF and c-kit protein in 8 of 11 (73%) cases. All three testicular cancer cell lines showed only faint staining reactions for c-kit protein and none for SCF. No secretion of SCF by the three lines in vitro was detected. The addition of high concentrations of SCF (100 ng/ml) to the testicular cancer cell lines in culture conditions without fetal calf serum resulted in a 1.4 to 3-fold growth stimulation compared to cell growth in serum-free medium alone. This effect was not detectable when the cells were cultured in serum-containing media. In the normal testicular tissue the germ-cells displayed a strong immunohistochemical reaction for c-kit protein while SCF positivity was found at the tubular membrane and on the surface of Sertoli cells. The SCF/c-kit system may possess a regulatory function in normal testicular tissue by possibly providing the microenvironment necessary for spermatogenesis. With the development of testicular cancer, this regulatory system seems to be lost, particularly in non-seminomatous germ-cell tumours. A growth-stimulatory effect of high concentrations of SCF on non-seminomatous testicular cancer cell lines can be detected only in culture conditions with serum-free media. The effects achievable by the combination of SCF with other growth factors need to be further studied, as well as the role of the c-kit/SCF regulatory system for normal spermatogenesis and its possible implications for the understanding and treatment of male infertility.

Treatment of clinical stage I testicular cancer and a possible role for new biological prognostic parameters.

Three different treatment strategies for patients with stage I non-seminomatous testicular cancer are available that will all result in long-term survival in more than 98% of the patients: a "wait and see" strategy with follow-up and chemotherapy in cases of tumour progression, retroperitoneal lymphadenectomy, with or without application of systemic chemotherapy, in cases of retroperitoneal metastases (pathological stage II disease) or primary adjuvant chemotherapy following inguinal orchiectomy. Each treatment strategy is associated with specific side-effects. In several studies histological characteristics of the primary tumour, particularly the presence of vascular invasion and of embryonal carcinoma cells, have been demonstrated to be significant prognostic factors for the risk of occult retroperitoneal metastases in patients with stage I disease. In addition, new biological prognostic factors determined by flow cytometry, cytogenetic analysis or molecular-biological DNA or RNA analysis have been investigated, among which alterations of the p53 tumour-suppressor gene may represent a promising new prognostic factor. Although alterations of p53 gene expression seem to be associated with advanced tumour stage and may predict retroperitoneal metastatic disease, the independent role of these molecular genetic alterations needs to be prospectively studied. Currently a risk-adapted treatment strategy based on the histological criteria of vascular invasion and the presence of embryonal carcinoma can be used to stratify patients into a "high-" and "low-risk" group with respect to tumour progression. While primary-nerve-sparing retroperitoneal lymphadenectomy or adjuvant chemotherapy with two cycles of platinum, etoposide and bleomycin may be appropriate for patients with a high risk (above 40%) for tumour progression, a "wait-and-see" strategy can be used for "low-risk" (less than 15% risk of progression) patients. Molecular investigations of prognostic factors may be able to improve further the stratification of patients into these different risk categories.

Immunohistochemical detection of cathepsin-d expression in prostate-cancer.

Lysosomal proteases may be involved in facilitating cancer invasion and metastatic spread by degradation of basement membranes and intercellular matrix. Overexpression of cathepsin D, a lysosomal aspartyl protease, has been reported in different tumours and seems to constitute a prognostic factor for survival in patients with breast cancer. The current study investigates immunohistochemical staining using anti-cathepsin D monoclonal antobodies (M1G8) in prostate cancer specimens and tissue from patients with benign prostatic hyperplasia (BPH). Among 41 tumours expression of cathepsin D was observed in 14 of 26 (54%) low stage and grade tumours (T-1-2/G(1-2)) and in 12 of 15 (86%) high stage and grade tumours (T-3, G(3)). Cathepsin D positivity was found within the cytoplasm and at the surface of tumour cells localized in glandular structures and in single cells invading the prostatic stroma, while no staining was observed in normal prostatic tissue and in mesenchymal cells. Two of ten specimens from patients with benign prostatic hyperplasia showed a weakly positive staining reaction within glandular structures. The clinical course of localized prostate cancer appears to be highly variable and the different treatment strategies (radical prostatectomy, radiation therapy or surveillance) have come under debate. For the determination of the biological aggressiveness of prostate cancer in the individual patient easily available biological prognostic factors are needed. This report demonstrates overexpression of cathepsin D in prostate cancer specimens with increasing frequency in patients with tumours of high grade and stage. The usefulness of cathepsin D immunohistochemistry as a prognostic factor should be prospectively evaluated.

Analysis of the cyclin-dependent kinase inhibitor p27Kip1 in muscle invasive bladder cancer.

It has been suggested that a deregulated cell cycle control contributes to the development of human malignancies due to the loss of critical antiproliferative mechanisms. The cell cycle is controlled at two checkpoints, one at the G1-S and another at the G2-M transition. Several genes including the structurally related p21WAF/CIP1 gene, the downstream mediator of the p53 tumor suppressor gene, and the p27Kip1 gene have been identified as inducers of cell cycle arrest at the G1 checkpoint when substantial DNA damage has occurred to avoid further replication of the altered genome. Recently, a heat stable 27 kDa protein, the transcript of the p27Kip1 gene, has been identified and was suggested to substantially participate in cell cycle control at the G1 checkpoint. Previous investigations have correlated decreased expression of the p27Kip1 protein with an increased biological aggressiveness of breast and small cell lung cancer. However, the molecular-genetic analysis of a variety of human malignancies including prostate cancer failed to identify any alteration at the p27Kip1 gene locus, therefore suggesting a loss of p27Kip1 protein expression to result from post-transcriptional/post-translational events or from so far unknown regulatory mechanisms. So far, bladder cancer specimens have neither been investigated for p27Kip1 alterations on the DNA level, nor has the result of molecular genetic analysis been correlated with an immunohistochemically detected expression of the gene product, the p27Kip1 protein. The present study is the first to describe p27Kip1 gene alterations on the DNA level in 3 of 42 muscle invasive bladder cancer specimens. In contrast, loss of p27Kip1 protein expression was observed in 14 of 42 (33%) tumors. According to the previously reported observation in a variety of human malignancies, in bladder cancer loss of p27Kip1 protein expression seems to result from post-transcriptional or post-translational events.

Predictive value of altered p27Kip1 and p21WAF/Cip1 protein expression for the clinical prognosis of patients with localized prostate cancer.

The p21WAF/Cip and the p27Kip1 genes have been identified as inductors of cell cycle arrest at the G1-checkpoint. Alterations of both genes have been suggested to be involved in the development of a variety of human malignancies due to a loss of critical antiproliferative mechanisms. To evaluate the prognostic importance of these alterations for patients with clinically localized prostate cancer, in 86 specimens (T1-T4) from 86 patients undergoing radical prostatectomy at the Department of Urology at Hannover University Medical School, were investigated. The immunohistochemical expression of the p27Kip1 and p21WAF/Cip protein was correlated to recurrence-free and long-term survival, age, depth of tumour infiltration, histological grade and lymph node status in these patients. After a median follow-up of 71 months (1-198 months), 14 of 20 (70%) patients (Group 1) with loss of p27Kip1 protein expression or a relative amount of < 10% of positively stained tumour cells developed recurrent disease in contrast to 18 of 66 (27%) patients (Group 2) with retained p27Kip1 protein expression (> or = 10% of positively stained tumour cells). The median recurrence-free survival times were 39 (4-134) months and 67 (4-198) months for patients in Groups 1 and 2 (p < 0.01), respectively. In multivariate analysis, loss of p27Kip1 protein expression was identified as the only independent prognostic parameter for recurrence-free survival. Univariate analysis (log-rank test) identified histological grading (p < 0.01) and reactivity for p27Kip1 (p = 0.046) (> or = 10% positivity) as prognostic factors for disease-specific long-term survival. However, during multivariate analysis none of the biological variables investigated retained independent prognostic importance regarding overall survival. Neither a low or a high expression of p21Waf/Cip could be correlated with the clinical prognosis of the patients following radical prostatectomy. This study confirms the independent prognostic value of decreased p27Kip1 protein expression in patients with localized prostate cancer, while a prognostic importance of p21Waf/Cip in addition to established patients' and tumour characteristics like tumour stage and histological grading appears rather unlikely.

The MXI1 tumor suppressor gene is not mutated in primary prostate cancer.

For prostate cancer, allelic deletions from the long arm of chromosome 10 (#10q23-25), the locus of the putative tumor suppressor gene MXI1 (#10q24-25), have been identified as a frequently occurring genetic event. During the development of several human malignancies, the c-myc proto-oncogene has been identified to enhance cellular transformation, mitogenesis and cell proliferation. The MXI1 gene, belonging to the helix-loop-helix (bHLH) gene family, was demonstrated to display tumor suppressor function by antagonizing c-myc induced transcriptional activities. Due to the detection of point mutations in the retained alleles of four primary adenocarcinomas of the prostate, MXI1 gene alterations have been suggested to be involved in the development and/or the progression of prostate cancer. To evaluate the role of MXI1 gene alterations for the development of adenocarcinoma of the prostate, 42 primary prostate cancers of different stage (T1-4) and histological grade (G1-3) were investigated for alterations within exons 4 and 5 of the MXI1 gene (spanning 6 exons in total), encoding for the functional HLH-Zip domain, by RNA-SSCP analysis and direct PCR-DNA-sequencing following the microscopically guided tumor cell dissection from 5 microm fresh-frozen buffer-soaked tissue sections. Even by application of this highly elaborated technical approach, MXI1 gene alterations could not be deleted in any of the tumor specimens investigated. Therefore, a substantial involvement of MXI1 gene alterations in the development of prostate cancer appears unlikely. The newly identified putative tumor suppressor gene PTEN, located at #10q23, might be responsible for the frequently observed allelic deletions from #10q23-25 in prostate cancer.

Prognostic value of p27Kip1 and p21WAF/Cip protein expression in muscle invasive bladder cancer.

Two genes, namely p27Kip1 and p21WAF/Cip1 that reveal distinct structural homology, have been identified as inductors of cell cycle arrest at the G1-checkpoint to prevent entry of somatic cells into the S phase of the cell cycle when substantial DNA damage has occurred. It was demonstrated that the p21WAF/Cip1 gene is induced by pathways dependent and independent from a functionally intact p53 tumour suppressor protein. It has been suggested that decreased expression both of the p21WAF/Cip1 and p27Kip1 protein may contribute to the development of human malignancies due to loss of critical antiproliferative mechanisms. So far, the role of altered p21WAF/Cip1 and mainly of a decreased p27Kip1 protein expression in patients with muscle invasive bladder cancer has not been investigated. In the present study, 50 tumour specimens from 50 patients undergoing radical cystectomy (T2-T4) were investigated for different biological and clinical characteristics as possible prognostic factors: age, depth of tumour infiltration (T-stage), histological grading (G), lymph node status as well as immunohistochemical staining for the p21WAF/Cip1 and p27Kip1 proteins. The median recurrence-free survival for patients with and without retained p21WAF/Cip1 protein expression was 54 months (3-86 months) and 13 months (1-40 months), respectively (p=0.07). During univariate analysis, loss of p21WAF/Cip1 protein expression (p=0.02), T-stage (p=0.02) and histological grading (p=0.03) were significant prognostic factors for survival, among which a negative reaction for the p21WAF/Cip1 protein (p=0.02) as well as T-stage (p=0.005) remained independent significant predictors during multivariate analysis. Loss of p27Kip1 protein expression was not correlated with the recurrence-free or the overall survival of the patients. Prospective studies are needed to confirm the independent prognostic potential of cell-cycle associated proteins such as p21WAF/Cip1 in patients with muscle invasive bladder cancer. The availability of more refined prognostic factors should assist decision making regarding the value of more aggressive treatment options, such as adjuvant or neoadjuvant chemotherapy, for defined subgroups of patients.

Overexpression of the p53 oncoprotein in carcinoma in situ of the testis.

Carcinoma in situ (CIS) is regarded as the precursor lesion of testicular germ cell tumors. In adults CIS cells have also been described within the normal testicular tissue adjacent to mature teratomas with a frequency of 52-88%. These CIS-cells can be identified by immunohistochemical staining for "placental like alkaline phosphatase" (PLAP). In four of eight patients with mature teratomas CIS was identified by immunohistochemistry for "PLAP" in atrophic testicular tubules adjacent to the tumors. In three of these patients cells of CIS were positive for the p53 oncoprotein, indicating a mutational inactivation of the p53 tumor suppressor gene. The malignant potential of mature teratomas, which do occur without histological signs of malignancy, may therefore be associated with the occurrence of CIS within the histologically normal appearing testicular tissue adjacent to the mature tumor. Immunohistochemical positivity for the p53 protein in CIS cells of some patients may indicate that the mutational inactivation of the p53 tumor suppressor gene could be involved early in the development of testicular germ cell tumors.

[New aspects on the identification of genetic alterations and prognostically important biological parameters in renal cell cancer]. / Prognostisch relevante biologische Marker für das Nierenzellkarzinom. Eine Bestandsaufnahme.

The observation of extremely variable clinical courses for patients with renal cell carcinomas of an identical pathological stage as well as a comparable histological differentiation resp. growth pattern strongly indicates the existence of tumors harboring different biological aggressiveness. Currently available histopathological classification systems do not predict the biological behaviour of renal cell cancer as sufficiently as the establishment of a therapeutical strategy adjusted to the individual patient would require. The need for a more refined characterization of the biological potential of the individual tumor results from the introduction of modified operative strategies as organ-preserving surgery, for example, as well as from the recently suggested application of an adjuvant systemic therapy adapted to the individual risk for tumor recurrence resp. the development of progressive disease. Therefore, the clinically orientated basic scientist and the basic scientifically orientated clinician intensively try to determine prognostically important biological variables which would allow to better predict the biological aggressiveness of a single tumor in addition to "classical" prognostic parameters (T-stage, histological grading, growth patterns). In this context, several biological parameters including the identification of alterations on the DNA-, RNA- and protein level have been discussed as possible biological prognostic markers for renal cell cancer. The present review tries to reflect currently available biological characteristics of RCC which might gain clinical importance with regard to an individualized therapy in the near future.

[Metastatic adult teratoma of the testis. Possibilities of chemotherapy and surgical treatment]. / Das metastasierte adulte Teratom des Hodens. Möglichkeiten der chemotherapeutischen und operativen Behandlung.

We report on a patient with the diagnosis of an adult teratoma metastasizing as choriocarcinoma. The 49-year-old man died of dysfunction of the liver caused by massive metastatic involvement. This case demonstrates the malignant potential of adult teratoma and emphasizes the need for chemotherapy of the same kind as for other malignant germ cell tumours if undifferentiated metastases of the teratoma are present. The chemotherapeutic modalities and the options for surgical treatment of metastatic adult teratomas of the testis are discussed.