[The impact of the androgen receptor splice variant AR-V7 on the prognosis and treatment of advanced prostate cancer]. / Bedeutung der Androgenrezeptor-Spleißvariante AR-V7 für Prognose und Therapie des fortgeschrittenen Prostatakarzinoms.

A recently discovered mechanism enabling prostate cancer cells to escape the effects of endocrine therapies consists in the synthesis of C-terminally truncated, constitutively active androgen receptor (AR) splice variants (AR-V). Devoid of a functional C-terminal hormone/ligand binding domain, various AR-Vs are insensitive to therapies targeting the androgen/AR signalling axis. Preliminary studies suggest that AR-V7, the most common AR-V, is a promising predictive tumour marker and a relevant selection marker for the treatment of advanced prostate cancer. This review critically outlines recent advances in AR-V7 diagnostics and presents an overview of current AR-V7 targeted therapies.

[Level IV inferior vena cava tumor thrombus : A rare diagnosis in patients with renal cell carcinoma]. / Level-IV-Cavathrombus : Eine seltene Diagnose bei Patienten mit Nierenzellkarzinom.

Renal cell carcinoma in combination with a supradiaphragmatic tumor thrombus is a rare tumor entity. Radical surgery including nephrectomy and thrombectomy is still considered standard treatment. The extent of the tumor thrombus should be preoperatively evaluated by MRI and TEE. An interdisciplinary team is important for surgery planning and realization. Despite the known risks of an operation, a longer overall survival is achieved.

F-18 labelled PSMA-1007: biodistribution, radiation dosimetry and histopathological validation of tumor lesions in prostate cancer patients.

PURPOSE: The prostate-specific membrane antigen (PSMA) targeted positron-emitting-tomography (PET) tracer 68Ga-PSMA-11 shows great promise in the detection of prostate cancer. However, 68Ga has several shortcomings as a radiolabel including short half-life and non-ideal energies, and this has motivated consideration of 18F-labelled analogs. 18F-PSMA-1007 was selected among several 18F-PSMA-ligand candidate compounds because it demonstrated high labelling yields, outstanding tumor uptake and fast, non-urinary background clearance. Here, we describe the properties of 18F-PSMA-1007 in human volunteers and patients. METHODS: Radiation dosimetry of 18F-PSMA-1007 was determined in three healthy volunteers who underwent whole-body PET-scans and concomitant blood and urine sampling. Following this, ten patients with high-risk prostate cancer underwent 18F-PSMA-1007 PET/CT (1 h and 3 h p.i.) and normal organ biodistribution and tumor uptakes were examined. Eight patients underwent prostatectomy with extended pelvic lymphadenectomy. Uptake in intra-prostatic lesions and lymph node metastases were correlated with final histopathology, including PSMA immunostaining. RESULTS: With an effective dose of approximately 4.4-5.5 mSv per 200-250 MBq examination, 18F-PSMA-1007 behaves similar to other PSMA-PET agents as well as to other 18F-labelled PET-tracers. In comparison to other PSMA-targeting PET-tracers, 18F-PSMA-1007 has reduced urinary clearance enabling excellent assessment of the prostate. Similar to 18F-DCFPyL and with slightly slower clearance kinetics than PSMA-11, favorable tumor-to-background ratios are observed 2-3 h after injection. In eight patients, diagnostic findings were successfully validated by histopathology. 18F-PSMA-1007 PET/CT detected 18 of 19 lymph node metastases in the pelvis, including nodes as small as 1 mm in diameter. CONCLUSION: 18F-PSMA-1007 performs at least comparably to 68Ga-PSMA-11, but its longer half-life combined with its superior energy characteristics and non-urinary excretion overcomes some practical limitations of 68Ga-labelled PSMA-targeted tracers.

Ecotropic viral integration site 1, a novel oncogene in prostate cancer.

Prostate cancer (PCa) is the most commonly diagnosed non-cutaneous cancer in men in the western world. Mutations in tumor suppressor genes and in oncogenes are important for PCa progression, whereas the role of stem cell proteins in prostate carcinogenesis is insufficiently examined. This study investigates the role of the transcriptional regulator Ecotropic Viral Integration site 1 (EVI1), known as an essential modulator of hematopoietic and leukemic stem cell biology, in prostate carcinogenesis. We show that in healthy prostatic tissue, EVI1 expression is confined to the prostate stem cell compartment located at the basal layer, as identified by the stem cell marker CD44. Instead, in a PCa progression cohort comprising 219 samples from patients with primary PCa, lymph node and distant metastases, EVI1 protein was heterogeneously distributed within samples and high expression is associated with tumor progression (P<0.001), suggesting EVI1 induction as a driver event. Functionally, short hairpin RNA-mediated knockdown of EVI1 inhibited proliferation, cell cycle progression, migratory capacity and anchorage-independent growth of human PCa cells, while enhancing their apoptosis sensitivity. Interestingly, modulation of EVI1 expression also strongly regulated stem cell properties (including expression of the stem cell marker SOX2) and in vivo tumor initiation capacity. Further emphasizing a functional correlation between EVI1 induction and tumor progression, upregulation of EVI1 expression was noted in experimentally derived docetaxel-resistant PCa cells. Importantly, knockdown of EVI1 in these cells restored sensitivity to docetaxel, in part by downregulating anti-apoptotic BCL2. Together, these data indicate EVI1 as a novel molecular regulator of PCa progression and therapy resistance that may control prostate carcinogenesis at the stem cell level.

[Metastasized prostate cancer. Position paper on the use of chemotherapy]. / Metastasiertes Prostatakarzinom. Positionspapier zum Einsatz der Chemotherapie.

BACKGROUND: Antihormonal and cytotoxic therapy options are available for the therapy of metastasized prostate cancer (mPC). Because no comparative studies are available, especially for castration-resistant prostate cancer (mCRCP), it remains unclear which patients will profit best from which therapy. OBJECTIVES: Previous data on the sequence of the various therapy options show that correct selection of the first line therapy for mCRPC can have an influence on the prognosis of the patient. In this position paper the various therapy options are critically illustrated and the clinical and pathohistological criteria for selection of the first line therapy of mCRPC are discussed. RESULTS: Molecular markers are an important aid for future patient selection and individualized therapy for optimal use of the available forms of therapy.

[Intratumoral heterogeneity in renal cell carcinoma. Molecular basis and translational implications]. / Intratumorale Heterogenität des Nierenzellkarzinoms. Molekulare Grundlagen und translationale Implikationen.

Advanced clear cell renal cell carcinoma is characterized by extensive intratumoral genomic heterogeneity and branched as well as convergent evolutionary traits with genomically different subclones evolving in parallel in the same tumor. Distinct driver mutations can be found in spatially separated subclones, which may hinder the development of novel targeted therapies. However, truncal mutations of the VHL tumor suppressor gene and chromosome 3p loss were ubiquitously detected and will hence continue to be a focus of future drug development. Nevertheless, genomic instability, enhanced tumor genome plasticity and intratumoral heterogeneity are likely to represent major challenges towards biomarker development and personalized patient care.

[Structure of biobanks for urological research]. / Struktur von Biobanken für die urologische Forschung.

Biomedical research plays an important role in the development of novel diagnostic procedures, drugs and treatment strategies with regard to cancerous and chronic inflammatory diseases. Biobanks are essential tools in this process. The complex structures and benefits of biobanks are presented in this article.

[Novel preclinical models and biomarkers for prostate cancer]. / Neue präklinische Modelle und Biomarker beim Prostatakarzinom.

The ultimate goal of a personalized approach to prostate cancer patient management relies on two prerequisites: the development of preclinical but clinically relevant model systems and robust prognostic and predictive biomarkers. The past several years have shown significant progress towards these two prerequisites which will be highlighted in this review using some notable examples.

[Urology in the concept of comprehensive cancer centers]. / Die Urologie im Konzept der "Comprehensive Cancer Center".

BACKGROUND: Urologic cancers comprise one quarter of all newly diagnosed cancers per year in Germany. In addition to the increasing incidence treatment of solid and hematological tumors has become more differentiated, complex and potentially more effective as well as more expensive. Following the example of the USA multidisciplinary translational comprehensive cancer centers (CCCs) have been established in Germany. The financial support from the government and nonprofit organizations, such as the German Cancer Aid aims to ensure and to optimize treatment of tumor patients now and in the future. Coupled with this development new funding opportunities for translational research are opening up for the participating clinical and scientific partners. DISCUSSION: Just as attractive and coherent integration of urology into the structures of a CCC where available appears to be, just as controversial is the professional modus operandi. Using the example of the National Center for Tumor Diseases in Heidelberg (NCT), the current manuscript discusses the risks and opportunities of this new centralized form of oncological care in urology. Detailed knowledge of organizational structures, clinical operations and funding is a prerequisite for any partner of a CCC to succeed in such a highly demanding environment as a specialty instead of becoming mere surgical proceduralists.

[Management of prostate cancer in the elderly]. / Management des Prostatakarzinoms in hohem Alter.

The management of prostate cancer in elderly patients is a topic of controversial discussion. The current guidelines recommend diagnosis and treatment of prostate cancer only in patients with a life expectancy of more than 10 years. Especially in elderly patients pre-existing comorbidities play a crucial role in life expectancy. In clinical practice mostly patient age alone is considered for the treatment decision; however, a guideline-based therapy of prostate cancer should also be offered to elderly patients. The treatment decision should be based on patient general health status and the oncological risk. The patient individual health status can be determined on the basis of comorbidities present and patient nutritional and performance status. For an optimal therapy regime the oncological risk has to be considered in treatment decisions. The aim of this article is to give an overview of risk stratification and treatment options for localized and metastatic prostate cancer in elderly patients.

Fanconi anemia deficiency stimulates HPV-associated hyperplastic growth in organotypic epithelial raft culture.

Fanconi anemia (FA) is a recessive genome instability syndrome characterized by heightened cellular sensitivity to DNA damage, aplastic anemia and cancer susceptibility. Leukemias and squamous cell carcinomas (SCCs) are the most predominant FA-associated cancers, with the latter exhibiting markedly early disease onset and aggressiveness. Although studies of hematopoietic cells derived from FA patients have provided much insight into bone marrow deficiencies and leukemogenesis, molecular transforming events in FA-deficient keratinocytes, which are the cell type of origin for SCC, are poorly understood. We describe here the growth and molecular properties of FANCA-deficient versus FANCA-corrected HPV E6/E7 immortalized keratinocytes in monolayer and organotypic epithelial raft culture. In response to DNA damage, FANCA-deficient patient-derived keratinocyte cultures displayed a G2/M phase arrest, senescence and apoptosis. Organotypic raft cultures exhibited DNA repair-associated defects with more 53BP1 foci and TdT-mediated dNTP nick end labeling-positive cells over their corrected counterparts. Interestingly, together with reduced rates of DNA damage, FA correction resulted in a marked decrease in epithelial thickness and the presence of fewer cell layers. The observed FANCA-mediated suppression of hyperplasia correlated with the detection of fewer cells transiting through the cell cycle in the absence of gross differentiation abnormalities or apoptotic differences. Importantly, the knockdown of either FANCA or FANCD2 in HPV-positive keratinocytes was sufficient for increasing epithelial hyperplasia. Our findings support a new role for FA pathways in the maintenance of differentiation-dependent cell cycle exit, with the implication that FA deficiencies may contribute to the high risk of FA patients for developing HPV-associated SCC.

Centriole overduplication through the concurrent formation of multiple daughter centrioles at single maternal templates.

Abnormal centrosome numbers are detected in virtually all cancers. The molecular mechanisms that underlie centrosome amplification, however, are poorly characterized. Based on the model that each maternal centriole serves as a template for the formation of one and only one daughter centriole per cell division cycle, the prevailing view is that centriole overduplication arises from successive rounds of centriole reproduction. Here, we provide evidence that a single maternal centriole can concurrently generate multiple daughter centrioles. This mechanism was initially identified in cells treated with the peptide vinyl sulfone proteasome inhibitor Z-L(3)VS. We subsequently found that the formation of more than one daughter at maternal centrioles requires cyclin E/cyclin-dependent kinase 2 as well as Polo-like kinase 4 and that overexpression of these proteins mimics this phenotype in the absence of a proteasome inhibitor. Moreover, we show that the human papillomavirus type 16 E7 oncoprotein stimulates aberrant daughter centriole numbers in part through the formation of more than one daughter centriole at single maternal templates. These results help to explain how oncogenic stimuli can rapidly induce abnormal centriole numbers within a single cell-division cycle and provide insights into the regulation of centriole duplication.

RNA polymerase II transcription is required for human papillomavirus type 16 E7- and hydroxyurea-induced centriole overduplication.

Aberrant centrosome numbers are detected in virtually all human cancers where they can contribute to chromosomal instability by promoting mitotic spindle abnormalities. Despite their widespread occurrence, the molecular mechanisms that underlie centrosome amplification are only beginning to emerge. Here, we present evidence for a novel regulatory circuit involved in centrosome overduplication that centers on RNA polymerase II (pol II). We found that human papillomavirus type 16 E7 (HPV-16 E7)- and hydroxyurea (HU)-induced centriole overduplication are abrogated by alpha-amanitin, a potent and specific RNA pol II inhibitor. In contrast, normal centriole duplication proceeded undisturbed in alpha-amanitin-treated cells. Centriole overduplication was significantly reduced by siRNA-mediated knock down of CREB-binding protein (CBP), a transcriptional co-activator. We identified cyclin A2 as a key transcriptional target of RNA pol II during HU-induced centriole overduplication. Collectively, our results show that ongoing RNA pol II transcription is required for centriole overduplication whereas it may be dispensable for normal centriole duplication. Given that many chemotherapeutic agents function through inhibition of transcription, our results may help to develop strategies to target centrosome-mediated chromosomal instability for cancer therapy and prevention.

Cyclin-dependent kinase 2 is dispensable for normal centrosome duplication but required for oncogene-induced centrosome overduplication.

Cyclin-dependent kinase 2 (CDK2) has been proposed to function as a master regulator of centrosome duplication. Using mouse embryonic fibroblasts (MEFs) in which Cdk2 has been genetically deleted, we show here that CDK2 is not required for normal centrosome duplication, maturation and bipolar mitotic spindle formation. In contrast, Cdk2 deficiency completely abrogates aberrant centrosome duplication induced by a viral oncogene. Mechanistically, centrosome overduplication in MEFs wild-type for Cdk2 involves the formation of supernumerary immature centrosomes. These results indicate that normal and abnormal centrosome duplication have significantly different requirements for CDK2 activity and point to a role of CDK2 in licensing centrosomes for aberrant duplication. Furthermore, our findings suggest that CDK2 may be a suitable therapeutic target to inhibit centrosome-mediated chromosomal instability in tumor cells.

Interleukin-12 inhibits apoptosis in chronic lymphatic leukemia (CLL) B cells.

The purpose of the present study was to investigate the effect of interleukin-12 on apoptosis of chronic lymphatic leukemia (CLL) B cells. Apoptotic indices were determined in highly purified CD5(+) B lymphocytes isolated from peripheral blood of seven patients with histologically confirmed CLL. Interleukin-4 as a known inhibitor of apoptosis was used as control. Quantitative analysis of apoptosis was determined by cell death detection ELISA. Our findings indicate that interleukin-12 inhibits ex vivo apoptosis in a large proportion of B-CLL patients and may be closely involved in the pathogenesis of disease. Therefore, our results may help identify potential new therapeutic targets in this malignancy.

Biological activities and molecular targets of the human papillomavirus E7 oncoprotein.

The human papillomavirus (HPV) E7 protein is one of only two viral proteins that remain expressed in HPV-associated human cancers. HPV E7 proteins share structural and functional similarities with oncoproteins encoded by other small DNA tumor viruses such as adenovirus E1A and SV40 large tumor antigen. The HPV E7 protein plays an important role in the viral life cycle by subverting the tight link between cellular differentiation and proliferation in normal epithelium, thus allowing the virus to replicate in differentiating epithelial cells that would have normally withdrawn from the cell division cycle. The transforming activities of E7 largely reflect this important function.

Participation of Survivin in mitotic and apoptotic activities of normal and tumor-derived cells.

Survivin is a member of the inhibitor of apoptosis (IAP) gene family, containing a single baculovirus IAP repeat (BIR) and no RING finger, that is expressed in many human cancers. Although it has been proposed to be involved in mitotic and cytokinetic processes, its functional subcellular distribution in the cytoplasm and nucleus, and its binding to centrosomes, spindle fibers, and centromeres in relation to these processes, is not fully resolved. We have analyzed the localization of Survivin in normal (Detroit 551, IMR-90) and tumor-derived (HeLa, Saos-2) cell lines, and found that it does colocalize with centrosomes in the cytoplasm during interphase, then moves to centromeres during mitosis, and finally localizes to the midbody spindle fibers during telophase. However, Taxol, a popular microtubule stabilizing agent that is frequently used in the study of these processes, severely disrupted the localization of Survivin. Taxol treatment of cells promoted extensive relocalization of Survivin with alpha-tubulin on microtubules during either interphase or mitosis. Survivin antisense oligonucleotide markedly sensitized HeLa cells to cell death induced by agents acting at the level of cell surface receptor (Fas pathway) or at the level of mitochondria (etoposide). HeLa cell death induced by Survivin antisense oligonucleotide could be partially complemented by Deterin, the Drosophila homolog of Survivin (Jones et al. [2000] J. Biol. Chem. 275:22157-22166). Reciprocally, a chimera of the Deterin BIR domain and Survivin C-terminus could rescue Drosophila Kc cells from death induced by transfection of a human caspase-7-expressing plasmid. These results indicate common components of Survivin and Deterin antiapoptotic action in the vertebrate and invertebrate phyla.

Centrosome abnormalities and genomic instability by episomal expression of human papillomavirus type 16 in raft cultures of human keratinocytes.

Primary human keratinocytes with ectopic expression of high-risk human papillomavirus (HPV) E6 and E7 oncoproteins display abnormal centrosome numbers, multipolar mitoses, and aneusomy. However, it has not been explored whether these abnormalities can occur in cells containing HPV episomes where E6 and E7 expression is under viral transcriptional control. Here, we demonstrate that centrosome abnormalities and genomic instability occur in organotypic raft cultures of human keratinocytes with episomal HPV-16 even at low copy numbers. We conclude that HPV-16 DNA, when maintained as an episome, can disturb centrosome homeostasis and subvert genomic integrity of the host cell during early stages of the viral infection.

Ki-67, cyclin E, and p16INK4 are complimentary surrogate biomarkers for human papilloma virus-related cervical neoplasia.

Prior studies of Ki-67, cyclin E, and p16 expression have suggested that these biomarkers may be preferentially expressed in cervical neoplasia. This study examined and compared the distribution of staining for these three antigens in 1) normal and reactive epithelial changes, 2) diagnostically challenging cases (atypical metaplasia and atypical atrophy), 3) squamous intraepithelial lesions (SIL), and 4) high-and low-risk human papilloma virus (HPV) type-specific SIL. One hundred four epithelial foci from 99 biopsies were studied, including low-grade squamous intraepithelial lesions (LSIL; 24), high-grade squamous intraepithelial lesions (HSIL; 36), mature or immature (metaplastic) squamous epithelium (29), and atrophic or metaplastic epithelium with atypia (15). Cases were scored positive for Ki-67 expression if expression extended above the basal one third of the epithelium, for cyclin E if moderate to strong staining was present, and for p16 if moderate to strong diffuse or focal staining was present. HPV status was scored by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis of extracted DNA. Immunohistochemical findings were correlated with histologic and viral data. Overall, a histologic diagnosis of SIL correlated strongly with all of the biomarkers used (p <0.001). Positive scores for Ki-67, cyclin E, and p16 were seen in 68.4%, 96.7%, and 100% of LSILs and 94.7%, 91.6%, and 100% of HSILs, respectively. Positive predictive values of these three biomarkers for HPV were 82.4%, 89.5%, and 91.4%, respectively. The positive predictive value for HPV of either cyclin E or p16 was 88.7%. Strong diffuse staining for p16 was significantly associated with high-risk HPV-associated lesions. Normal or reactive epithelial changes scored positive for the three biomarkers in 7.7%, 8.0%, and 12%, respectively. Limitations in specificity included minimal or no suprabasal staining for Ki-67 in immature condylomas and occasional suprabasal staining of reactive epithelial changes (10%), diffuse weak nuclear cyclin E staining in some normal or metaplastic epithelia, and diffuse weak basal p16 staining and occasional stronger focal positivity in normal epithelia. Ki-67, cyclin E, and p16 are complementary surrogate biomarkers for HPV-related preinvasive squamous cervical disease. (Because cyclin E and p16 are most sensitive for LSIL and HSIL [including high-risk HPV], respectively, use of these biomarkers in combination for resolving diagnostic problems, with an appreciation of potential background staining, is recommended.)