[Attitudes towards psychotherapy in South Korea and Germany : A cross-cultural comparative study]. / Einstellungen gegenüber Psychotherapie in Südkorea und Deutschland : Eine kulturvergleichende Studie.

BACKGROUND: Due to the relatively recent introduction of psychotherapy in South Korea and against the background of collectivist and Confucian values, it has been suggested that South Koreans harbor more negative attitudes towards psychotherapy compared to Germans and that the social acceptance of psychotherapy is lower. METHODS: We compared the attitudes of 99 women from South Korea with 98 German women using the questionnaire on attitudes towards psychotherapeutic treatment (FEP). For the study of the South Korean women we translated the questionnaire into the Korean language. RESULTS: The results of the psychometric analysis suggest that the Korean version of the FEP is of acceptable quality. South Korean women reported a significantly more negative attitude towards psychotherapy compared to German women. Furthermore, South Korean women anticipated a more skeptical social attitude towards psychotherapy compared to Germans. CONCLUSION: The presented results suggest the relevance of cultural imprinting in psychotherapy. They are discussed with respect to culture-specific self-concepts, concepts of disease and healing expectations and the increase of individualistic values in the Korean society.

A novel network analysis tool to identify relationships between disease states and risks for red blood cell alloimmunization.

We hypothesized that diagnoses may be associated with alloantibody 'responder' status and examined associations between disease states and alloimmunization. Patients with ≥1 alloantibody and non-alloimmunized controls were analysed. Pearson's coefficients were calculated to determine associations between alloimmunization and diseases; significant correlations were selected to construct a network. Inflammatory disorders and diseases requiring chronic transfusion support were associated with responder status. Mitigation steps may be considered in patients with these disorders.

Uptake of Neonicotinoid Insecticides by Water-Foraging Honey Bees (Hymenoptera: Apidae) Through Guttation Fluid of Winter Oilseed Rape.

The water-foraging activity of honey bees (Apis mellifera L.) on guttation fluid of seed-coated crops, such as winter oilseed rape (WOR; Brassica napus L.), has not yet been evaluated. We analyzed the uptake of active substances (a.s.) in guttation fluid by evaluating residues of honey-sac contents. In autumn, insecticide residues of up to 130 µg a.s. per liter were released in WOR guttation fluid; this concentration is noticeably lower than levels reported in guttation fluid of seed-coated maize. Until winter dormancy, the concentrations declined to <30 µg a.s. per liter. In spring, residues were linked to prewintered plants and declined steadily until flowering. The maximum release of residues in guttation fluid of seed-coated WOR occurs on the first leaves in autumn when the colonies' water demand decreases. For the first time, proof for the uptake of guttation fluid from seed-coated WOR by honey bees was provided by measuring residues in individual honey-sac contents. In total, 38 out of 204 samples (19%) showed residues of thiamethoxam at concentrations ranging from 0.3 to 0.95 µg per liter while the corresponding concentrations in guttation fluid of WOR varied between 3.6 to 12.9 µg thiamethoxam per liter. The amounts of thiamethoxam we found in the honey sacs of water-foraging honey bees were therefore below the thresholds in nectar and pollen that are considered to have negative effects on honey bees after chronic exposure.

[Depression and anxiety disorders among psoriasis patients: protective and exacerbating factors]. / Depression und Angststörung bei Psoriasispatienten: Schutz- und Risikofaktoren.

BACKGROUND: Psoriasis is associated with higher risk for depression and anxiety disorders. Yet the complex system linking disease symptoms with physical and mental outcomes is poorly understood. OBJECTIVES: The central aim of this study was to identify physical, psychological, and social factors that exacerbate or protect against the perception of symptoms of depression and anxiety among individuals starting in-patient treatment for psoriasis. Another aim was to investigate if improved clinical status of the psoriasis is associated with improved psychological and physical wellbeing one year after treatment. MATERIALS AND METHODS: In this follow-up study a sample of 381 psoriasis in-patients in Germany were questioned before starting treatment and one year after treatment (166 participants) using instruments to measure socioeconomic variables, perceived somatic severity, life quality (DLQI, SF-8), feelings of stigmatization (QES), and depression and anxiety (HADS-D). Coping (Trier Coping Scale) and pathological worry (PSWQ-PW) were also measured at the initial time point. Multiple regression analyses of variance for repeated measurements and of correlation were conducted. RESULTS: Self-reported symptoms of anxiety and depression were higher than in normal populations. Perceived severity of physical symptoms was not correlated with depression or anxiety at the initial time point. The strongest predictors of depression and anxiety in our sample were measures of life quality. Life quality was predicted in a large part by stigmatization. Increased momentary symptom severity and increased perceived discomfort over time was not associated with increased perception of symptoms of depression. CONCLUSIONS: Our findings extend previous research on the importance of stigmatization for quality of life to the specific outcome of depression and anxiety. It confirms the desirability of early screening of psoriasis patients for depression and anxiety and initiating treatment by a qualified therapist.

Perceived relationships between severity of psoriasis symptoms, gender, stigmatization and quality of life.

BACKGROUND: Psoriasis is a skin disease with negative physical, psychological and social repercussions for those affected, but we still lack knowledge of how somatic and non-somatic factors directly and indirectly combine to affect patients' quality of life (QoL). OBJECTIVES: This study seeks a better understanding of the relations between symptom severity, discomfort, stigmatization, gender and QoL among psoriasis patients. METHODS: The sample comprised 381 psoriasis patients in inpatient care. Symptom severity and discomfort were measured subjectively with single items. Stigmatization was measured with the Questionnaire on Experience with Skin Complaints. QoL was measured using the Dermatology Life Quality Index (DLQI) and the Short Form-8 Health Survey (SF-8). RESULTS: Symptom severity was associated with higher discomfort, stigmatization and lower skin-related QoL. Symptom severity correlated weakly with more general aspects of QoL as measured by the SF-8. Men and women reported different experiences with discomfort, stigmatization and mental aspects of QoL (SF-8 mental component summary score). Some stigmatization parameters function as mediating variables between symptom severity and QoL. CONCLUSIONS: Our findings suggest that the effect of stigmatization on skin-related QoL is driven by symptom severity and stigmatization combined, whereas its effect on mental health is driven mostly by stigmatization alone. Further, although women and men experience the social impact of psoriasis differently, the effect of stigmatization on QoL is similar for both genders.

MIF is a common genetic determinant of COVID-19 symptomatic infection and severity.

BACKGROUND: Genetic predisposition to coronavirus disease 2019 (COVID-19) may contribute to its morbidity and mortality. Because cytokines play an important role in multiple phases of infection, we examined whether commonly occurring, functional polymorphisms in macrophage migration inhibitory factor (MIF) are associated with COVID-19 infection or disease severity. AIM: To determine associations of common functional polymorphisms in MIF with symptomatic COVID-19 or its severity. METHODS: This retrospective case-control study utilized 1171 patients with COVID-19 from three tertiary medical centers in the USA, Hungary and Spain, together with a group of 637 pre-pandemic, healthy control subjects. Functional MIF promoter alleles (-794 CATT5-8,rs5844572), serum MIF and soluble MIF receptor levels, and available clinical characteristics were measured and correlated with COVID-19 diagnosis and hospitalization. Experimental mice genetically engineered to express human high- or low-expression MIF alleles were studied for response to coronavirus infection. RESULTS: In patients with COVID-19, there was a lower frequency of the high-expression MIF CATT7 allele when compared to healthy controls [11% vs. 19%, odds ratio (OR) 0.54 [0.41-0.72], P < 0.0001]. Among inpatients with COVID-19 (n = 805), there was a higher frequency of the MIF CATT7 allele compared to outpatients (n = 187) (12% vs. 5%, OR 2.87 [1.42-5.78], P = 0.002). Inpatients presented with higher serum MIF levels when compared to outpatients or uninfected healthy controls (87 ng/ml vs. 35 ng/ml vs. 29 ng/ml, P < 0.001, respectively). Among inpatients, circulating MIF concentrations correlated with admission ferritin (r = 0.19, P = 0.01) and maximum CRP (r = 0.16, P = 0.03) levels. Mice with a human high-expression MIF allele showed more severe disease than those with a low-expression MIF allele. CONCLUSIONS: In this multinational retrospective study of 1171 subjects with COVID-19, the commonly occurring -794 CATT7MIF allele is associated with reduced susceptibility to symptomatic SARS-CoV-2 infection but increased disease progression as assessed by hospitalization. These findings affirm the importance of the high-expression CATT7MIF allele, which occurs in 19% of the population, in different stages of COVID-19 infection.

Single-photon emission from electrically driven InP quantum dots epitaxially grown on CMOS-compatible Si(001).

The heteroepitaxy of III-V semiconductors on silicon is a promising approach for making silicon a photonic platform. Mismatches in material properties, however, present a major challenge, leading to high defect densities in the epitaxial layers and adversely affecting radiative recombination processes. However, nanostructures, such as quantum dots, have been found to grow defect-free even in a suboptimal environment. Here we present the first realization of indium phosphide quantum dots on exactly oriented Si(001), grown by metal-organic vapour-phase epitaxy. We report electrically driven single-photon emission in the red spectral region, meeting the wavelength range of silicon avalanche photodiodes' highest detection efficiency.

Stem cells in the biology of normal urothelium and urothelial carcinoma.

Urothelium is a special type of stratified epithelium that lines the distal portion of the urinary tract. For a long time, basal urothelial cells have been suspected to include a population of urothelial stem cells. Recent experiments identifying label-retaining cells as well as lineage tracing analyses corroborate this notion. There are striking morphological and antigenic similarities between basal or differentiated urothelial cells and the corresponding cells in some urothelial carcinomas. In this respect, basal cell-specific markers provide good candidates to identify urothelial carcinoma stem cells, e.g. specific cytokeratins (CK5, CK14, CK17) or adhesion molecules (specific integrin subspecies, CD44). Common properties of the stem cells of normal urothelium and urothelial cancer have thus emerged. Both are characterized by a remarkable plasticity and both rely on reciprocal interactions with stromal fibroblasts. However, the stem cells of individual urothelial carcinomas appear to differ considerably and may contribute to the heterogeneity of this disease. The presence, quantity, and particular biological nature of urothelial carcinoma stem cells in each case may thus carry important clinical information that might allow a rationale stratification of urothelial cancer patients for treatment in the near future.

KDM6A mutations promote acute cytoplasmic DNA release, DNA damage response and mitosis defects.

BACKGROUND: KDM6A, encoding a histone demethylase, is one of the top ten mutated epigenetic cancer genes. The effect of mutations on its structure and function are however poorly characterized. METHODS: Database search identified nonsense and missense mutations in the N-terminal TPR motifs and the C-terminal, catalytic JmjC domain, but also in the intrinsically disordered region connecting both these two well-structured domains. KDM6A variants with cancer-derived mutations were generated using site directed mutagenesis and fused to eGFP serving as an all-in-one affinity and fluorescence tag to study demethylase activity by an ELISA-based assay in vitro, apoptosis by FACS, complex assembly by Co-immunoprecipitation and localization by microscopy in urothelial cells and apoptosis by FACS. RESULTS: Independent of the mutation and demethylase activity, all KDM6A variants were detectable in the nucleus. Truncated KDM6A variants displayed changes in complex assemblies affecting (1) known interactions with the COMPASS complex component RBBP5 and (2) KDM6A-DNA associated assemblies with the nuclear protein Nucleophosmin. Some KDM6A variants induced a severe cellular phenotype characterized by multiple acute effects on nuclear integrity, namely, release of nuclear DNA into the cytoplasm, increased level of DNA damage indicators RAD51 and p-γH2A.X, and mitosis defects. These damaging effects were correlated with increased cell death. CONCLUSION: These observations reveal novel effects of pathogenic variants pointing at new specific functions of KDM6A variants. The underlying mechanisms and affected pathways have to be investigated in future research to understand how tumor cells cope with and benefit from KDM6A truncations.

[Report from the 9th symposium of the German Association for Bladder Cancer Research]. / Bericht vom 9. Symposium des Deutschen Forschungsverbunds Blasenkarzinom.

The annual symposium of the German Research Association for Bladder Carcinoma (DFBK) was organized on February 7th and 8th, 2020, in Düsseldorf. On the first day, eight international guest speakers invited by the DFBK and the Department of Urology of the Heinrich Heine University Düsseldorf presented the current state of research on bladder cancer (BC). Topics were genomic changes and molecular classification in non-muscle-invasive and muscle-invasive BC, prospects and limits of proteome technology in urine diagnostics, function of chromatin regulators in bladder carcinogenesis, cellular reactions to aneuploidy, organoid technology and biobanking, as well as novel aspects of immunotherapy for BC. The second day was dedicated to new results and ideas of the DFBK members on BC pathomechanisms, diagnostics and therapeutic approaches, and most importantly, discussions on the further development of collaborative projects. Additional information is available at http://www.forschungsverbund-blasenkarzinom.de.

DKC1 overexpression associated with prostate cancer progression.

BACKGROUND: Dyskerin encoded by the DKC1 gene is a predominantly nucleolar protein essential for the formation of pseudouridine in RNA and the telomerase RNA subunit hTR. Inherited mutations inactivating dyskerin cause dyskeratosis congenita, a syndrome with progeroid features characterised by skin defects and haematopoiesis failure, as well as cancer susceptibility. In this study, we report DKC1 overexpression in prostate cancers. METHODS: Expression of DKC1 was measured by quantitative RT-PCR in prostate cancer tissues in relation to hTR and the proliferation marker MKI67. Effects of dyskerin downregulation on proliferation, apoptosis and senescence of prostate cancer cell lines were determined. RESULTS: DKC1 was significantly overexpressed in prostate cancers, particularly in high-stage and recurring cases, correlating moderately with hTR and MKI67. Dyskerin downregulation in prostate carcinoma cell lines by siRNA diminished cell proliferation, but elicited neither apoptosis nor senescence. Apoptosis induction by TNF-alpha or tunicamycin was not enhanced. Long-term downregulation led predominantly to cell shrinking and loss of adhesion. INTERPRETATION: DKC1 upregulation in prostate cancers is common and likely to be necessary for extensive tumour growth. The phenotype of prostate carcinoma cell lines after dyskerin downregulation suggests that its most critical function is sustaining protein biosynthesis. Intriguingly, compromised function and overexpression of dyskerin can both contribute to cancer development.

Dynamic expression pattern of the myc protooncogene in midgestation mouse embryos.

The c-myc protooncogene in mouse embryos was shown by RNA in situ hybridization to be preferentially expressed in tissues of endodermal and mesodermal origin. Most organs developing from the ectoderm, such as skin, brain, and spinal cord, displayed low levels of c-myc RNA. The thymus represented the only hematopoietic organ with high c-myc expression. In organs and structures strongly hybridizing to c-myc probes, for example the fetal part of the placenta, gut, liver, kidney, pancreas, submandibular glands, enamel organs of the molars, and skeletal cartilage, the level of expression depended on the stage of development. Expression was observed to be correlated with proliferation, particularly during expansion and folding of partially differentiated epithelial cells.

Electrically pumped single-photon emission in the visible spectral range up to 80 K.

We present an electrically pumped single-photon emitter in the visible spectral range, working up to 80 K, realized using a self-assembled single InP quantum dot. We confirm that the electroluminescense is emitted from a single quantum dot by performing second-order autocorrelation measurements and show that the deviation from perfect single-photon emission is entirely related to detector limitations and background signal. Emission from both neutral and charged exciton complexes was observed with their relative intensites depending on the injection current and temperature.

[Bladder carcinoma cell lines as models of the pathobiology of bladder cancer. Review of the literature and establishment of a new progression series]. / Harnblasenkarzinomzelllinien als Modellsysteme zur Pathobiologie des Harnblasenkarzinoms. Uberblick und Etablierung einer neuen Progressionsserie.

BACKGROUND: Tumour cell lines represent valuable preclinical models to decipher underlying biology and identify potential therapy targets and pharmacologically useful compounds. Approximately 50 human bladder cancer cell lines have been established to date, mainly from invasive and metastatic tumours. Two of these, namely T24 and 253J, were experimentally further developed into progression series. These models have provided important insights into later tumour progression events and metastatic dissemination. Only a few cell lines are available as models of non-invasive papillary bladder cancer and no progression series have yet been established. MATERIAL AND METHODS: During the course of establishing a doxorubicin-resistant variant cell line of the human papillary bladder carcinoma cell line BFTC-905, a unique cell colony was identified, apparently involving cells with divergent growth patterns. Subsequent subculturing yielded three daughter cell lines, BFTC-905-compact, BFTC-905-diffuse und BFTC-905-diffuse M. Their fundamental characterization included basic cell morphology, cell membrane expression of E-Cadherin, karyotype analysis, invasion and colony forming capacity in soft agar. The clonal origin of the newly established daughter cell lines was assessed by means of molecular genetic methods. RESULTS: We could identify important differences in multiple transformation related traits among the cell lines of the BFTC-905 progression series. Both diffuse cell lines (BFTC-905-diffuse und BFTC-905-diffuse M) differed from the BFTC-905-compact cell line by growing in a less organized,"diffuse" manner, which involved colonies of cells exhibiting apparently normal cell-to-cell adhesion as well as individual cells outside of them. This diminution of the cell-to-cell adhesion was accompanied by a corresponding decrease of membranous E-Cadherin. The BFTC-905-diffuse M cell line displayed a dramatic increase in the overall chromosome number, resulting in a hypertetraploid karyotype. At the same time, this cell line, as the only one in the progression series, acquired the ability to grow independent of anchorage in soft agar. All three cell lines remained noninvasive. Allelic distribution of highly polymorphic DNA-markers in the cell lines of the BFTC-905 progression series provided unequivocal evidence of their common origin. CONCLUSION: The newly established BFTC-905 progression series manifests two aspects of the early progression of non-invasive bladder carcinoma, not exhibited by any other progression series published so far, namely dynamic changes in the expression of E-Cadherin and a complex karyotypic evolution. It may thus contribute important insights into further understanding of the pathobiology of bladder cancer.

An ecotoxicological view on neurotoxicity assessment.

The numbers of potential neurotoxicants in the environment are raising and pose a great risk for humans and the environment. Currently neurotoxicity assessment is mostly performed to predict and prevent harm to human populations. Despite all the efforts invested in the last years in developing novel in vitro or in silico test systems, in vivo tests with rodents are still the only accepted test for neurotoxicity risk assessment in Europe. Despite an increasing number of reports of species showing altered behaviour, neurotoxicity assessment for species in the environment is not required and therefore mostly not performed. Considering the increasing numbers of environmental contaminants with potential neurotoxic potential, eco-neurotoxicity should be also considered in risk assessment. In order to do so novel test systems are needed that can cope with species differences within ecosystems. In the field, online-biomonitoring systems using behavioural information could be used to detect neurotoxic effects and effect-directed analyses could be applied to identify the neurotoxicants causing the effect. Additionally, toxic pressure calculations in combination with mixture modelling could use environmental chemical monitoring data to predict adverse effects and prioritize pollutants for laboratory testing. Cheminformatics based on computational toxicological data from in vitro and in vivo studies could help to identify potential neurotoxicants. An array of in vitro assays covering different modes of action could be applied to screen compounds for neurotoxicity. The selection of in vitro assays could be guided by AOPs relevant for eco-neurotoxicity. In order to be able to perform risk assessment for eco-neurotoxicity, methods need to focus on the most sensitive species in an ecosystem. A test battery using species from different trophic levels might be the best approach. To implement eco-neurotoxicity assessment into European risk assessment, cheminformatics and in vitro screening tests could be used as first approach to identify eco-neurotoxic pollutants. In a second step, a small species test battery could be applied to assess the risks of ecosystems.

Disruption of the FA/BRCA pathway in bladder cancer.

Bladder carcinomas frequently show extensive deletions of chromosomes 9p and/or 9q, potentially including the loci of the Fanconi anemia (FA) genes FANCC and FANCG. FA is a rare recessive disease due to defects in anyone of 13 FANC genes manifesting with genetic instability and increased risk of neoplasia. FA cells are hypersensitive towards DNA crosslinking agents such as mitomycin C and cisplatin that are commonly employed in the chemotherapy of bladder cancers. These observations suggest the possibility of disruption of the FA/BRCA DNA repair pathway in bladder tumors. However, mutations in FANCC or FANCG could not be detected in any of 23 bladder carcinoma cell lines and ten surgical tumor specimens by LOH analysis or by FANCD2 immunoblotting assessing proficiency of the pathway. Only a single cell line, BFTC909, proved defective for FANCD2 monoubiquitination and was highly sensitive towards mitomycin C. This increased sensitivity was restored specifically by transfer of the FANCF gene. Sequencing of FANCF in BFTC909 failed to identify mutations, but methylation of cytosine residues in the FANCF promoter region was demonstrated by methylation-specific PCR, HpaII restriction and bisulfite DNA sequencing. Methylation-specific PCR uncovered only a single instance of FANCF promoter hypermethylation in surgical specimens of further 41 bladder carcinomas. These low proportions suggest that in contrast to other types of tumors silencing of FANCF is a rare event in bladder cancer and that an intact FA/BRCA pathway might be advantageous for tumor progression.

Methylation of endogenous human retroelements in health and disease.

Retroelements constitute approximately 45% of the human genome. Long interspersed nuclear element (LINE) autonomous retrotransposons are predominantly represented by LINE-1, nonautonomous small interspersed nuclear elements (SINEs) are primarily represented by ALUs, and LTR retrotransposons by several families of human endogenous retroviruses (HERVs). The vast majority of LINE and HERV elements are densely methylated in normal somatic cells and contained in inactive chromatin. Methylation and chromatin structure together ensure a stable equilibrium between retroelements and their host. Hypomethylation and expression in developing germ cells opens a "window of opportunity" for retrotransposition and recombination that contribute to human evolution, but also inherited disease. In somatic cells, the presence of retroelements may be exploited to organize the genome into active and inactive regions, to separate domains and functional regions within one chromatin domain, to suppress transcriptional noise, and to regulate transcript stability. Retroelements, particularly ALUs, may also fulfill physiological roles during responses to stress and infections. Reactivation and hypomethylation of LINEs and HERVs may be important in the pathophysiology of cancer and various autoimmune diseases, contributing to chromosomal instability and chronically aberrant immune responses. The emerging insights into the pathophysiological importance of endogenous retroelements accentuate the gaps in our knowledge of how these elements are controlled in normal developing and mature cells.

Analysis of DNA methylation in single circulating tumor cells.

Direct analysis of circulating tumor cells (CTCs) can inform on molecular mechanisms underlying systemic spread. Here we investigated promoter methylation of three genes regulating epithelial-to-mesenchymal transition (EMT), a key mechanism enabling epithelial tumor cells to disseminate and metastasize. For this, we developed a single-cell protocol based on agarose-embedded bisulfite treatment, which allows investigating DNA methylation of multiple loci via a multiplex PCR (multiplexed-scAEBS). We established our assay for the simultaneous analysis of three EMT-associated genes miR-200c/141, miR-200b/a/429 and CDH1 in single cells. The assay was validated in solitary cells of GM14667, MDA-MB-231 and MCF-7 cell lines, achieving a DNA amplification efficiency of 70% with methylation patterns identical to the respective bulk DNA. Then we applied multiplexed-scAEBS to 159 single CTCs from 11 patients with metastatic breast and six with metastatic castration-resistant prostate cancer, isolated via CellSearch (EpCAMpos/CKpos/CD45neg/DAPIpos) and subsequent FACS sorting. In contrast to CD45pos white blood cells isolated and processed by the identical approach, we observed in the isolated CTCs methylation patterns resembling more those of epithelial-like cells. Methylation at the promoter of microRNA-200 family was significantly higher in prostate CTCs. Data from our single-cell analysis revealed an epigenetic heterogeneity among CTCs and indicates tumor-specific active epigenetic regulation of EMT-associated genes during blood-borne dissemination.

Concomitant down-regulation of SPRY1 and SPRY2 in prostate carcinoma.

Sprouty proteins encoded by the SPRY genes act as modulators and feedback inhibitors of signalling by epidermal growth factor (EGF) and fibroblast growth factor (FGF). Overactivity of EGF and FGF signalling common in prostate cancer might therefore be exacerbated by Sprouty down-regulation. Indeed, down-regulation of SPRY1 and SPRY2 expression has been independently reported. We found both genes modestly down-regulated by microarray expression analysis of microdissected prostate cancers and by quantitative RT-PCR in macrodissected specimens compared with benign tissues. Importantly, the decreases paralleled each other and expression levels of both genes were significantly lower in cancers that recurred within the average follow-up period of 32 months. In contrast to a previous report, no hypermethylation was found to accompany down-regulation of SPRY2 in cancer tissues and cell lines. We additionally investigated the expression of an SPRY1 alternative transcript presumed to be specific for fetal tissues and found its expression moderately well correlated with expression of the standard transcript through diverse tissues and cell lines. The present study confirms and extends previous reports by demonstrating concomitant down-regulation and a significant association with recurrence of SPRY genes.

Hypomethylation of L1 LINE sequences prevailing in human urothelial carcinoma.

Alterations of DNA methylation were investigated in 6 urothelial carcinoma cell lines and 13 tumor tissues. The methylation of L1 LINE sequences was diminished in all cell lines (by 26 +/- 5%; range, 11-49%) and in most tumors (by 21 +/- 5%; range, 0-60%) compared to normal bladder mucosa. Hypermethylation of the calcitonin gene CpG island was restricted to cell lines and was not found in primary tumors, suggesting it had arisen during culture. In single-cell clones of a urothelial carcinoma cell line, both hypomethylation of L1 sequences and hypermethylation of the calcitonin gene persisted, indicating that they coexist within one cell. DNA methyltransferase expression did not correlate with the methylation status of the cell lines, but rather with histone H3 expression. Accordingly, it was down-regulated in quiescent cells. Aberrant expression of DNA methyltransferase is therefore not likely the cause for altered methylation patterns in urothelial carcinoma. L1 LINE hypomethylation seems to prevail in urothelial carcinoma and in this tumor might be useful for diagnostic or prognostic purposes.