[Translational research and diagnostics of melanoma]. / Translationale Forschung und Diagnostik beim Melanom.

Although early stage malignant melanoma (MM) has a favorable prognosis five year survival rate is poor (<10%) in patients suffering from distant metastases. Due to molecular typing of MM recently high response rates were achieved in metastatic MM by using specific inhibitors directed against the mutated form of BRAF kinase, e.g. Vemurafinib and Dabrafinib. Therefore BRAF mutation analysis has become standard of care in advanced MM and pathologists are urged to provide a quality guaranteed molecular diagnostics. However, squamous neoplasias (e. g., keratoacanthomas) and recurrences of MM mostly within 6 months during targeted therapy point to the need of further translational research. Thus new drugs, such as MEK inhibitors, based on the MAP-kinase pathway downstream of BRAF have already effectively been used. Finally, the impact of molecular characteristics in different subtypes of MM (acral, mucosal, uveal) will be discussed with respect to their specific mutational spectrum (e.g. cKIT , NRAS , GNAQ).

[Anal cancer: diagnostic and differential diagnostic issues]. / Das Analkanalkarzinom: Diagnostische und differenzialdiagnostische Aspekte.

Tumors of the anal canal are mostly epithelial in origin. The transition of gland-forming rectal mucosa via specialized urothelium-like cells at the dentate line to anal non-keratinized and finally perianal keratinized squamous epithelium implies a broad spectrum of tumor types, with most cancers exhibiting a mixture of different histological features. Moreover, secondary neoplasias extending into or metastasizing to the anal region need to be considered. Based on epithelial metaplasia at the transformation zone, poorly differentiated squamous anal carcinomas may show co-expression of both the squamous (CK5/6) and glandular type keratins (CK7). Since HPV infection of high-risk types (often 16 and 18) is etiologically associated with anal cancer, p16(INK4a) is highly sensitive and specific in the detection of high-grade anal squamous intraepithelial neoplasias (ASIN) and corresponding invasive squamous carcinomas. Diagnosis of secondary malignancies, including pagetoid extension into the anogenital region, requires the application of specific immunohistochemical marker panels.

[Rare intramuscular haemangioma of the sternocleidomastoid muscle]. / Seltenes intramuskuläres Hämangiom des M. sternocleidomastoideus.

Intramuscular tumours of the head and neck often represent a differential diagnostic challenge. We report the rare case of an intramuscular haemangioma arising from the sternocleidomastoid muscle in the 6th decade. Pre-operative diagnosis was difficult, as these tumours are extremely uncommon in the head and neck region, with only very few cases reported in the literature. Due to the marked tendency of intramuscular hemangiomas to recur, accurate preoperative diagnosis forms the basis of adequate surgical therapy with sufficient safety margins.

Papular exanthem discloses acute myeloid leukaemia: interphase fluorescence in situ hybridization revealed deletion of p53 and gain at 8q22/8q24/Tel8q without trisomy 8.

We describe a 79-year-old patient who presented with fatigue, weight loss, pancytopenia and a papular exanthem. Previous attempts to taking bone-marrow biopsies had resulted in a 'dry tap', with no material collected, suggesting idiopathic myelofibrosis. Histological examination of skin biopsies showed dermal infiltration of monocytoid cells, resulting in a diagnosis of acute myeloid leukaemia (French-American-British M5 morphology) with leukaemia cutis (LC). Numerous abnormalities of chromosome 8 (trisomy or tetrasomy) have been identified in association with LC. We performed fluorescent in situ analysis on cutaneous tissue using directly labelled probes for various gene loci often involved in patients with AML; these tests showed deletion of p53 and excluded trisomy 8. However, application of probes for AML/ETO, MYC and telomere 8q revealed a gain at 8q22/8q24/8q telomere in a significant number of infiltrating cells. We hypothesize that a partial gain at 8q rather than trisomy of the whole chromosome 8 exhibits an association with LC in AML.

[Active surveillance of localized prostate cancer. Significance of prostate core needle biopsies]. / Active Surveillance des lokalisierten Prostatakarzinoms. Wertigkeit der Prostatastanzbiopsie.

Today, more than 80% of men diagnosed with prostate cancer (PCA) by PSA screening do not die from the sequelae of their disease. About 70% present with early, organ-confined cancer and almost half of them are small (<5 cm(3)) without evidence of progression over years (insignificant PCA). It is assumed that screening brings the diagnosis of PCA forward by about 9 years and that in almost one third of these cases immediate radical prostatectomy or radiotherapy would result in overtreatment. Thus, the treatment strategy of "active surveillance" with selective but delayed intervention for patients with organ-confined PCA could be an attractive alternative to the known curative therapy options. However, a prerequisite of such a therapeutic approach would be a precise identification of patients at high risk for cancer progression. Careful work-up of prostate core needle biopsies including improved pre-embedding preparation and detailed interpretation are of the utmost importance. A Gleason score < or =6 and tumor in only one or two cores are considered predictive of organ-confined cancer. Pathologists should concentrate on correct Gleason scoring in core needle biopsies and identification of lesions that exclude a patient from active surveillance.

Transcriptional profiling of transurethral resection samples provides insight into molecular mechanisms of hormone refractory prostate cancer.

The molecular mechanisms for hormone-resistant prostate cancer progression still remain elusive, mainly due to the limited availability of corresponding tissue. As transurethral resection (TUR) is a common palliative therapy for patients with hormone refractory prostate cancer (HRPC) who have subvesical obstruction, we aimed to demonstrate that TUR samples can be used to identify significantly affected biological pathways during the switch to HRPC using oligonucleotide microarray analysis. Among the most significantly deregulated pathways in HRPC, we observed an induction of oxidative phosphorylation and a repression of cytoskeletal components.

[Sinushistiocytosis with massive lymphadenopathy (Rosai-Dorfman disease)]. / Sinushistiozytose mit massiver Lymphadenopathie (Rosai-Dorfman-Erkrankung).

Sinus histiocytosis with massive lymphadenopathy (SHML) is a rare, painless lymphoproliferative disorder of unknown origin with a usually benign course. About 40% of the patients show an extranodal involvement with skin being the most common site in 27% of these patients. We describe a patient with widespread disease involving the respiratory tract, kidneys and skin. Histopathology revealed the characteristic features of SHML with emperipolesis and immunohistochemical positivity of histiocytes for S100 and macrophage-associated antigens.

STAT-1 decoy oligonucleotide improves microcirculation and reduces acute rejection in allogeneic rat small bowel transplants.

During acute rejection leukocyte-endothelial cell interaction fuelled by costimulatory molecules such as the CD40/CD154 receptor/ligand dyad disrupts microcirculation of the small bowel. Downregulating endothelial CD40 expression by employing a decoy oligonucleotide (dODN) neutralizing the transcription factor signal transducer and activator of transcription-1 (STAT-1) may protect the graft. Therefore allogenic small bowel transplantation was performed in the Brown Norway to Lewis rat model. Graft vessels were pretreated with STAT-1 dODN, mutant control ODN (20 microM) or vehicle (n=8). CD40 antisense ODN and scrambled control ODN-treated transplants served as target control (n=3 each). Intravital microscopy, histology, immunohistochemistry and Western blot analyses were performed 7 days later. Functional capillary density, red blood cell velocity and perfusion index in STAT-1 dODN and CD40 antisense ODN-treated transplants were improved whereas stasis index was reduced. Leukocyte-endothelial cell interaction showed no difference. Histological parameters of rejection, infiltrating CD3-positive cells and apoptotic bodies were also reduced in STAT-1 dODN and CD40 antisense ODN-treated transplants 7 days post-transplantation. CD40 protein abundance was reduced to less than 10% of control in STAT-1 dODN-treated grafts. STAT-1 dODN blockade of CD40 expression improves mucosal perfusion, reduces graft rejection, T-cell infiltration and apoptosis in rat small bowel allografts during acute rejection.

Parvovirus B19 detected in Rosai-Dorfman disease in nodal and extranodal manifestations.

Sinus histiocytosis with massive lymphadenopathy (SHML), also designated as Rosai-Dorfman disease (RDD), is a rare benign reactive lymphoproliferative disorder. It is defined by a characteristic histopathology with sinus histiocytosis and haemophagocytosis known as emperipolesis. In histiocytes S100 is strongly expressed, whereas CD1a staining typically is negative. The disease mainly manifests at a single lymph node; however, multilocular and extranodal affection can occur. Causative infectious agents, and virus infections in particular, have repeatedly been suspected, although until now the origin of the disease has been unclear. Four cases of RDD (two nodal sites and two extranodal upper respiratory tract sites) were analysed for parvovirus B19 (B19) infection by immunohistochemistry to detect B19 capsid proteins VP1/VP2. In all the four cases, huge numbers of B19-positive cells were partly detected. The positive cells were identified either as lymphocytes or, in one extranodal case, also as respiratory epithelial cells. This is the first report of B19 infection in RDD tissue, indicating that B19 may be associated with the pathogenesis of SHML.

Increased number of mature dendritic cells in Crohn's disease: evidence for a chemokine mediated retention mechanism.

BACKGROUND AND AIMS: Activation of T cells by dendritic cells (DC) is thought to play a pivotal role in induction and maintenance of Crohn's disease. Detailed analyses however concerning the phenotype and maturation of DC as well as the mechanisms underlying their recruitment are still lacking for Crohn's disease. METHODS: Different myeloid and plasmacytoid DC subsets were characterised by immunohistochemistry. Expression of the so-called "lymphoid" chemokines CCL19, CCL20, and CCL21 was determined by real time reverse transcription-polymerase chain reaction in Crohn's disease and normal controls. Furthermore, expression of CCL19, CCL20, and CCL21 as well as their receptors CCR6 (for CCL20) and CCR7 (for CCL19 and CCL21) was characterised by immunohistochemistry and, in addition, their cellular localisation was determined by double immunofluorescence investigations. RESULTS: Colonic tissue affected by Crohn's disease was characterised by an increased number of mature myeloid DC forming clusters with proliferating T cells. In keeping with their advanced maturation, DC possess the chemokine receptor CCR7. Increased expression of the CCR7 ligands CCL19 by DC themselves as well as CCL21 by reticular cells and lymphatic vessels was observed in Crohn's disease, thereby causing the matured DC to be trapped at the site of inflammation. CONCLUSION: Our results demonstrate that autocrine and paracrine actions of lymphoid chemokines in Crohn's disease may lead to increased numbers of mature DC away from their usual migration to lymphoid organs and result in the development of a tertiary lymphatic tissue within the bowel wall maintaining the autoimmune inflammation in Crohn's disease.

CD4+ CD56+ blastic tumor of the skin: cytogenetic observations and further evidence of an origin from plasmocytoid dendritic cells.

We here report on a case of a blastic tumor, recently described to belong to a new entity sharing phenotypic similarities with blood derived plasmocytoid dendritic cells and formerly regarded as belonging to the group of natural killer cell lymphomas. Besides immunophenotypic characteristics such as the absence of T- cell markers and almost complete absence of markers of the myeloid lineage, these tumors express CD4, CD56 and CD123, the receptor for interleukin-3. Moreover, using the comparative genomic hybridisation technique, CGH, we demonstrate a gain of chromosome 7q, 22 and a loss of chromosome 3p and 13q. Since this type of hematologic disorder often shows its primary manifestation in the skin and often runs a rapidly fatal course, it is important to distinguish this from other types of primary cutaneous lymphomas.

Glucocorticoid receptor expression in inflammatory bowel disease: evidence for a mucosal down-regulation in steroid-unresponsive ulcerative colitis.

BACKGROUND: Glucocorticoids (GC) play a major role in the attenuation of inflammation. Glucocorticoid receptor (GR) expression is an important determinant of steroid sensitivity. AIMS: To investigate whether GR mRNA expression is altered in inflammatory bowel disease, and whether GR mRNA expression correlates with disease activity and may predict response to GC therapy. METHODS: Mucosal biopsies were taken from 33 patients with ulcerative colitis, 21 with Crohn's disease and 11 controls. Peripheral blood mononuclear cells were isolated from 24 ulcerative colitis and 18 Crohn's disease patients and 11 controls. GR mRNA was measured by quantitative reverse transcriptase polymerase chain reaction (RT-PCR), and correlated to endoscopic findings, clinical activity and outcome of GC therapy. In a subset of subjects GR localisation was shown by immunohistochemistry. RESULTS: In patients with inflammatory bowel disease GR expression was not different from controls. However, GR was decreased in biopsies from ulcerative colitis patients with impaired GC response. The inhibitory subtype GRbeta was expressed 100-1000 times lower than GRalpha. GR immunoreactivity was identified in immune and epithelial cells except for colonic crypts. CONCLUSION: In inflammatory bowel disease systemic and mucosal GR mRNA expression is not altered. However, in ulcerative colitis patients, low mucosal GR expression may predict the outcome of GC therapy. The low expression of GRbeta challenges its role in steroid refractoriness in inflammatory bowel disease.

Molecular evidence of organic ion transporters in the rat adrenal cortex with adrenocorticotropin-regulated zonal expression.

Experimental evidence suggested that secretion of steroid hormones from adrenocortical cells involves carrier-mediated transport: Cortisol release from, and uptake of p-[3H]aminohippurate into, bovine adrenocortical cells showed properties of the renal p-[3H]aminohippurate/anion exchanger OAT1. Other poly-specific transporters such as organic anion-transporting polypeptides (oatps) and organic cation transporters (OCTs) could also be involved in steroid hormone release. A homology-cloning procedure was established to detect these transporters in rat adrenal gland cDNA. PCR revealed the presence of OAT1, oatp1, oatp2, and oatp3. In situ hybridization localized OAT1 in the outer zona fasciculata, oatp3 in the zona glomerulosa, and oatp1 and oatp2 in the inner zona fasciculata and outer zona reticularis. An OCT2-specific probe produced signals in the zona glomerulosa and outer zona fasciculata. Pretreatment of rats with ACTH increased the expression of OAT1 mRNA that spread to all zones, and hypophysectomy strongly decreased it. A less pronounced regulation was detected for OCT2 and oatp3. Specific antibodies confirmed the localization of OAT1 in the outer zona fasciculata, supporting a possible role of OAT1 in cortisol release. The zonated distribution of transporters furthermore suggest that oatp1-3 and OCT2 may be important for the endocrine function of rat adrenocortical cells.

Cirrhotic livers reveal genetic changes in the MDM2-P14ARF system of cell cycle regulators.

The genesis of hepatocellular carcinoma is promoted by changes in the regulatory MDM2-P14ARF system. The incidence of such changes has to date not been analysed in non-tumourous livers showing regenerative proliferation. In the present study, 24 cirrhotic livers of alcohol-, autoimmue disorder- or HCV-caused genesis were screened for MDM2-P14ARF alterations at the level of protein, DNA and mRNA. Using confocal laser scanning microscopy, the absence of MDM2 and P14ARF expression was detected in all samples except three HCV-infected livers (four livers) which contained hepatocytes overexpressing MDM2 (P14ARF) protein. In two of the samples lacking P14ARF expression, laser microdissection and PCR demonstrated deletion of the P14ARF gene. The P14ARF gene amplified from other specimens did not carry mutations. MDM2 splicing variants were present in tissues from alcohol- and autoimmune disorder-induced cirrhoses. Sequencing of full-size mRNA revealed a MDM2 mis-sense mutation in an alcohol-induced cirrhosis. One sample contained regenerative nodules with genetic instability occurring at MDM2 locus D12S83 according to the data of automatic PCR fragment analysis. In summary, this study gives first evidence for different types of MDM2 and P14ARF alterations in cirrhotic livers. We suggest that the changes impair the regulatory MDM2-P14ARF system, thus possibly favouring regenerative proliferation and transformation.

Interleukin 16 expression and phenotype of interleukin 16 producing cells in Crohn's disease.

BACKGROUND: The mechanisms involved in the initiation and maintenance of Crohn's disease are poorly understood. Previous studies have demonstrated an increased number of infiltrating CD4+ T cells within the inflammatory affected bowel wall in Crohn's disease. Novel therapy approaches using anti-CD4 antibodies are thought to be effective in Crohn's disease. AIMS: Interleukin 16 (IL-16) has been characterised as a chemokine with selective chemoattraction for CD4+ inflammatory T cells. In this study, cellular expression of IL-16 in Crohn's disease and ulcerative colitis was investigated. METHODS: Expression of IL-16 was analysed in tissue samples of Crohn's disease, ulcerative colitis, and normal controls by applying reverse transcription-polymerase chain reaction, non-radioactive in situ hybridisation, and immunohistochemistry. Double staining methods were used to characterise cells expressing IL-16. The amount of infiltrating CD4+ cells was determined by immunohistochemistry and correlated with the corresponding IL-16+ cell number by step sections. RESULTS: An increased number of IL-16+ cells in Crohn's disease in comparison with ulcerative colitis and control probes was demonstrated. IL-16 was expressed by CD4 and CD8 positive T cells. In addition, in active Crohn's disease there was a substantial number of IL-16 positive mast cells. The increased number of CD4+ lymphocytes correlated positively with the increased number of IL-16 positive cells in Crohn's disease. CONCLUSION: Our results demonstrate that increased expression of IL-16 in T cells and mast cells in active Crohn's disease is associated with increased numbers of CD4+ lymphocytes. Local expression of IL-16 seems to play a significant role in the initiation and persistence of the inflammatory process in Crohn's disease, presumably by IL-16 mediated recruitment of CD4+ cells, mostly lymphocytes, into the bowel wall.

Expression of the T-cell chemoattractant chemokine lymphotactin in Crohn's disease.

Recruitment of lymphocytes is a prominent feature of the inflammatory process in Crohn's disease (CD). The present study was undertaken to investigate the expression of the novel lymphocyte-specific chemoattractant lymphotactin (Lptn) as a potential regulatory factor for the recruitment of T cells in CD. The expression of Lptn mRNA was quantified in resection specimens of patients with CD in comparison to normal controls without signs of inflammation by real-time quantitative reverse transcriptase-polymerase chain reaction and localized by nonradioactive in situ hybridization. Furthermore, the phenotype of cells expressing Lptn mRNA was characterized. In contrast to normal controls Lptn mRNA was significantly increased in tissue samples affected by CD. Cells expressing Lptn were identified as T cells, mast cells, and unexpectedly dendritic cells. Lptn mRNA was found to be up-regulated on stimulation with phorbol-12-myristate-13-acetate and concanavalin A in T cells isolated from peripheral blood, which could be prevented by dexamethasone, cyclosporine A, and FK506. A similar regulation mechanism could be identified for the Lptn receptor GPR-5 in peripheral T cells. In addition, Lptn mRNA expression could be induced in mature monocyte-derived dendritic cells. The results indicate that local expression of Lptn by activated T cells and to a lesser extent by mast cells and dendritic cells represents a key regulator for lymphocyte trafficking and maintenance of the inflammatory process observed in CD, which might be partly mediated through an autocrine/paracrine pathway of activated T cells.

Engagement of the Fc epsilon RI stimulates the production of IL-16 in Langerhans cell-like dendritic cells.

Preferential uptake and presentation of IgE-bound allergens by epidermal Langerhans cells (LC) via the high affinity IgE receptor, FcepsilonRI, is regarded as an important mechanism in the induction of cutaneous inflammation in atopic dermatitis. Here, we show that activation of monocyte-derived LC-like dendritic cells (LLDC) through engagement of FcepsilonRI induces the expression of IL-16, a chemoattractant factor for dendritic cells, CD4+ T cells, and eosinophils. We found that ligation of FcepsilonRI on LLDC derived from atopic dermatitis patients that express high levels of FcepsilonRI increases IL-16 mRNA expression and storage of intracellular IL-16 protein and enhances the secretion of mature IL-16 in a biphasic manner. An early release of IL-16 (peak at 4 h) is independent of protein synthesis, while a more delayed release (peak at 12 h) requires protein synthesis and occurs subsequent to the induction of IL-16 mRNA and intracellular accumulation of pro-IL-16. There was evidence that LLDC use caspase-1 to process IL-16, as inhibition of caspase-1, but not of caspase-3, partially prevented the release of IL-16 in response to ligation of FcepsilonRI. In an in vivo model of IgE-dependent LC activation, the atopy patch test, positive skin reactions were also associated with the induction of IL-16 in epidermal dendritic cells. These data indicate that IL-16 released from LC after allergen-mediated activation through FcepsilonRI may link IgE-driven and cellular inflammatory responses in diseases such as atopic dermatitis.

Response of psoriasis to interleukin-10 is associated with suppression of cutaneous type 1 inflammation, downregulation of the epidermal interleukin-8/CXCR2 pathway and normalization of keratinocyte maturation.

Psoriasis is a chronic inflammatory skin disease in which epidermal hyperplasia results from the release of cytokines by infiltrating type 1 T cells. Up- regulation of endogenous interleukin-10 controls type 1 skin responses in animal models; however, interleukin-10 production is low in psoriatic lesions. Consistent with an important role of interleukin-10 in psoriasis, we and colleagues have recently demonstrated clinical efficacy of subcutaneous administration of recombinant interleukin-10 to affected patients. Here, we studied the effects of interleukin-10 on disease-related inflammatory pathways. Patients were treated with recombinant interleukin-10 over 6 wk in an open-label phase II clinical trial. Tissue was obtained before and after therapy and examined by histology/immunohistochemistry, in situ hybridization, and quantitative real-time reverse transcription-polymerase chain reaction. Ten of 14 patients showed a marked reduction of the clinical disease activity. The clinical response was associated with a significant decrease of cutaneous T cell infiltration and the lesional expression of type 1 cytokines interferon-gamma and tumor necrosis factor-alpha. Interleukin-10 inhibited the epidermal interleukin-8 pathway by downregulating the expression of interleukin-8, its receptor CXCR2, and its inducer interleukin-17, and partially reversed the aberrant keratinocyte maturation defining psoriatic epidermal pathology. Remarkably, there was evidence that genetic factors are involved in the response to interleukin-10 as individual variations in the downregulation of tumor necrosis factor-alpha were related to the presence of polymorphisms in the tumor necrosis factor-alpha promoter. These data suggest that excessive production of type 1 cytokines in human skin disease can be counter-regulated by the administration of recombinant interleukin-10. Genotypic analysis may help to identify patients that will preferentially respond to interleukin-10 therapy.

Relationship between GAGE-1/-2 expression, EBV infection and interferon-gamma expression in undifferentiated carcinoma of nasopharyngeal type.

GAGE-1/-2 proteins are novel tumour markers, functionally related to tumour rejection. The objective of the present study was to identify the existence of a relationship between GAGE-1/-2 expression, Epstein Barr Virus (EBV) infection and viral infection-induced cytokine expression in cultivated tumour cells and archival specimens of undifferentiated carcinoma of nasopharyngeal type (UCNT). PCR and in situ hybridization techniques were employed. In cultivated UCNT cells, interferon-gamma (IFN-gamma) induced synthesis of GAGE-1/-2 mRNA. In archival tumour specimens (n = 10) however, GAGE-1/-2 gene expression was detected in only 3/8 cases with coincident EBV infection and IFN-gamma expression. In conclusion, EBV infection appears to induce IFN-gamma gene expression in most tumors, but GAGE-1/-2 expression in only some tumours. The role of IFN-gamma and other factors in triggering GAGE-1/-2 gene activation must be elucidated further. The relevance of GAGE-1/-2 gene expression and its detection by PCR for future immunotherapy is discussed.