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Featured researches published by Gian Kayser.


International Journal of Cancer | 2009

Merkel cell polyomavirus sequences are frequently detected in nonmelanoma skin cancer of immunosuppressed patients

Ahmad Kassem; Kristin Technau; Anna Kordelia Kurz; Deepa Pantulu; Marie Löning; Gian Kayser; Elmar Stickeler; Wolfgang Weyers; Carlos Diaz; Martin Werner; Dorothee Nashan; Axel zur Hausen

Recently, a new human polyoma virus has been identified in Merkel cell carcinomas (MCC). MCC is a highly aggressive neuroendocrine nonmelanoma skin cancer (NMSC) associated with immunosuppression. Clonal integration of this virus which was termed Merkel cell polyoma virus (MCPyV) was reported in a number of MCC. Squamous cell carcinoma (SCC) and basal cell carcinoma (BCC) are also NMSC and are the most frequent cancers in the setting of immunosuppression. A unique group of 56 NMSC from 11 immunosuppressed patients and 147 NMSC of 125 immunocompetent patients was tested for MCPyV by DNA PCR, targeting the Large T Antigen and the structural Viral Protein 1. NMSC included SCC, BCC and Bowens disease (BD). In addition, normal skin and 89 colorectal cancers were tested. MCPyV specific sequences were significantly more frequently found in NMSC of immunosuppressed patients compared to immunocompetent patients (p < 0.001). In particular BD and BCC revealed a significant increased association of MCPyV of immunosuppressed patients (p = 0.002 and p = 0.006). Forty‐seven of 147 (32%) sporadic NMSC were MCPyV positive. Interestingly, 37.5% (36/96) of sporadic BCC of immunocompetent patients were MCPyV positive. No MCPyV was detected within normal skin and only 3 out of 89 of additionally tested colorectal cancers were MCPyV positive. Our data show that MCPyV is a frequently reactivated virus in immunocompromized patients. How MCPyV contributes to the pathogenesis of NMSC, i.e., BD, SCC and BCC, in immunosuppressed patients and in addition, potentially to the pathogenesis of a subset of sporadic BCC needs further investigations.


Hpb | 2010

A simple scoring system based on clinical factors related to pancreatic texture predicts postoperative pancreatic fistula preoperatively.

Ulrich F. Wellner; Gian Kayser; Hryhoriy Lapshyn; Olivia Sick; Frank Makowiec; J Höppner; Ulrich T. Hopt; Tobias Keck

BACKGROUND Postoperative pancreatic fistula (POPF) is regarded as the most serious complication of pancreatic surgery. The preoperative risk stratification of patients by simple means is of interest in perioperative clinical management. METHODS Based on prospective data, we performed a risk factor analysis for POPF after pancreatoduodenectomy in 62 patients operated between 2006 and 2008 with special focus on clinical parameters that might serve to predict POPF. A predictive score was developed and validated in an independent second dataset of 279 patients operated between 2001 and 2010. RESULTS Several pre- and intraoperative factors, as well as underlying pathology, showed significant univariate correlation with rate of POPF. Multivariate analysis (binary logistic regression) disclosed soft pancreatic texture (odds ratio [OR] 10.80, 95% confidence interval [CI] 1.80-62.20) and history of weight loss (OR 0.15, 95% CI 0.04-0.66) to be the only independent preoperative clinical factors influencing POPF rate. The subjective assessment of pancreatic hardness by the surgeon correlated highly with objective assessment of pancreatic fibrosis by the pathologist (r = -0.68, P < 0.001, two-tailed Spearmans rank correlation). A simple risk score based on preoperatively available clinical parameters was able to stratify patients correctly into three risk groups and was independently validated. CONCLUSIONS Preoperative stratification of patients regarding risk for POPF by simple clinical parameters is feasible. Pancreatic texture, as evaluated intraoperatively by the surgeon, is the strongest single predictive factor of POPF. The findings of the study may have important implications for perioperative risk assessment and patient care, as well as for the choice of anastomotic techniques.


American Journal of Pathology | 2009

Essential Role of Osteopontin in Smoking-Related Interstitial Lung Diseases

Antje Prasse; Mirjam Stahl; Guido Schulz; Gian Kayser; Lingqiao Wang; Kjetil Ask; Jasmin Yalcintepe; Andreas Kirschbaum; Elena Bargagli; Gernot Zissel; Martin Kolb; Joachim Müller-Quernheim; Johannes M. Weiss; Andreas C. Renkl

Smoking-related interstitial lung diseases are characterized by the accumulation of macrophages and Langerhans cells, and fibrotic remodeling, which are linked to osteopontin (OPN) expression. Therefore, OPN levels were investigated in bronchoalveolar lavage (BAL) cells in 11 patients with pulmonary Langerhans cell histiocytosis (PLCH), 15 patients with desquamative interstitial pneumonitis (DIP), 10 patients with idiopathic pulmonary fibrosis, 5 patients with sarcoidosis, 13 otherwise healthy smokers, and 19 non-smoking controls. Furthermore, OPN overexpression was examined in rat lungs using adenoviral gene transfer. We found that BAL cells from patients with either PLCH or DIP spontaneously produced abundant amounts of OPN. BAL cells from healthy smokers produced 15-fold less OPN, and those cells from non-smoking healthy volunteers produced no OPN. BAL cells from patients with either idiopathic pulmonary fibrosis or sarcoidosis produced significantly less OPN, as compared with patients with PLCH. These data were confirmed by immunochemistry. Nicotine stimulation increased production of both OPN and granulocyte-macrophage colony stimulating factor by alveolar macrophages from smokers. Nicotinic acetylcholine receptor expression resembled the pattern of spontaneous OPN production and was dramatically increased in both PLCH and DIP. OPN overexpression in rat lungs induced lesions similar to PLCH with marked alveolar and interstitial accumulation of Langerhans cells. Our findings suggest a pathogenetic role of increased OPN production in both PLCH and DIP by promoting the accumulation of macrophages and Langerhans cells.


Diagnostic Pathology | 2010

Lactate-Dehydrogenase 5 is overexpressed in non-small cell lung cancer and correlates with the expression of the transketolase-like protein 1

Gian Kayser; Ahmad Kassem; Wulf Sienel; Luzie Schulte-Uentrop; Dominik Mattern; Konrad Aumann; Elmar Stickeler; Martin Werner; Bernward Passlick; Axel zur Hausen

AimsAs one of the five Lactate dehydrogenase (LDH) isoenzymes, LDH5 has the highest efficiency to catalyze pyruvate transformation to lactate. LDH5 overexpression in cancer cells induces an upregulated glycolytic metabolism and reduced dependence on the presence of oxygen. Here we analyzed LDH5 protein expression in a well characterized large cohort of primary lung cancers in correlation to clinico-pathological data and its possible impact on patient survival.MethodsPrimary lung cancers (n = 269) and non neoplastic lung tissue (n = 35) were tested for LDH5 expression by immunohistochemistry using a polyclonal LDH5 antibody (ab53010). The results of LDH5 expression were correlated to clinico-pathological data as well as to patients survival. In addition, the results of the previously tested Transketolase like 1 protein (TKTL1) expression were correlated to LDH5 expression.Results89.5% (n = 238) of NSCLC revealed LDH5 expression whereas LDH5 expression was not detected in non neoplastic lung tissues (n = 34) (p < 0.0001). LDH5 overexpression was associated with histological type (adenocarcinoma = 57%, squamous cell carcinoma = 45%, large cell carcinoma = 46%, p = 0.006). No significant correlation could be detected with regard to TNM-stage, grading or survival. A two sided correlation between the expression of TKTL1 and LDH5 could be shown (p = 0.002) within the overall cohort as well as for each grading and pN group. A significant correlation between LDH5 and TKTL1 within each histologic tumortype could not be revealed.ConclusionsLDH5 is overexpressed in NSCLC and could hence serve as an additional marker for malignancy. Furthermore, LDH5 correlates positively with the prognostic marker TKTL1. Our results confirm a close link between the two metabolic enzymes and indicate an alteration in the glucose metabolism in the process of malignant transformation.


Head and Neck-journal for The Sciences and Specialties of The Head and Neck | 2007

ULTRASOUND-GUIDED CORE-NEEDLE BIOPSY IN THE DIAGNOSIS OF HEAD AND NECK MASSES: INDICATIONS, TECHNIQUE, AND RESULTS

Jens Pfeiffer; Gian Kayser; Katja Technau-Ihling; Carsten Christof Boedeker; Gerd Jürgen Ridder

Unclear cervicofacial masses are common presentations that often require tissue sampling to guide therapy. While open biopsy is invasive, fine‐needle aspiration cytology includes a high rate of nondiagnostic samples.


Pathology | 2011

Poor outcome in primary non-small cell lung cancers is predicted by transketolase TKTL1 expression

Gian Kayser; Wulf Sienel; Britta Kubitz; Dominik Mattern; Elmar Stickeler; Bernward Passlick; Martin Werner; Axel zur Hausen

Aim: Malignant tumours ferment glucose to lactate even in the presence of sufficient oxygen (the Warburg effect). Transketolases seem to be involved in this metabolic switch. TKTL1 has previously been shown to encode a transketolase-like enzyme which is overexpressed in colon, urothelial and breast cancer. Here we investigated the prognostic impact of TKTL1 expression in non-small cell lung cancer (NSCLC). Methods: Curatively operated NSCLCs of 201 patients were analysed for TKTL1 expression by immunohistochemistry (clone JFC12T10). Statistical analyses with regard to clinicopathological parameters included Kaplan-Meier and multivariate Cox regression analyses. Results: There was no or mild TKTL1 expression in 89 tumours (44.7%), whereas in 110 tumours (55.3%) TKTL1 was overexpressed. TKTL1 overexpression correlated with tumour-type (p = 0.02) and histological grading (p = 0.033) and was significantly associated with poor patient survival (p = 0.008). In addition, TKTL1 overexpression identified patients with poor clinical outcome among lymph node negative (p = 0.039) and well to moderately differentiated (p = 0.005) NSCLCs; furthermore, it proved to be an independent prognostic factor (p = 0.0252). Conclusion: Our data suggest that TKTL1 overexpression is a new and independent predictor of survival for patients with NSCLC. Since inhibition of transketolase enzyme reactions has recently been shown to effectively suppress tumour growth, TKTL1 represents a novel pharmacodiagnostic marker.


Otolaryngology-Head and Neck Surgery | 2005

Solitary neurofibroma of the maxillary sinus and pterygopalatine fossa.

Carsten Christof Boedeker; Gerd Jürgen Ridder; Gian Kayser; J. Schipper; Wolfgang Maier

Neurofibromas are benign, heterogeneous peripheral nerve sheath tumors that arise from the connective tissue of peripheral nerve sheaths, especially the endoneurium. They may occur as isolated, sporadic lesions but are much more common in association with neurofibromatosis type 1 (NF-1), which also is known as von Recklinghausen’s disease. Solitary neurofibromas of the maxillary sinus are exceedingly rare tumors. Our purpose in presenting this unusual case is to describe the clinical and histopathologic features, the presentation on magnetic resonance imaging (MRI), and the differential diagnosis as well as the management of a solitary neurofibroma of the maxillary sinus and pterygopalatine fossa.


The Journal of Pathology | 2006

Centrosome-, chromosomal-passenger- and cell-cycle-associated mRNAs are differentially regulated in the development of sporadic colorectal cancer.

Ulrike Gerlach; Gian Kayser; Axel Walch; Ulrich T. Hopt; Jürgen Schulte-Mönting; Martin Werner; Silke Lassmann

Dysregulation of the centrosome complex and chromosomal segregation has been associated with aneuploid cells and aggressive solid tumours, but the relevance of this mechanism to the adenoma–carcinoma sequence of sporadic colorectal cancer (sCRC), especially tumours showing chromosomal instability (CIN), is still unknown. In a series of matching normal epithelial cells (n = 41), dysplastic cells (n = 18), and invasive carcinoma cells (n = 41) from cases with sCRC, mRNA levels of the centrosomal kinase Aurora‐A/STK15 and the chromosomal passenger‐ and cell cycle‐associated molecules Incenp, Survivin, Mad‐2, and Cyclin‐D1 were therefore measured with specific reference to the type of genetic instability. Compared with normal epithelium, significant up‐regulation of mRNAs was already present for Aurora‐A/STK15 (p = 0.0313) in dysplastic cells and for all investigated markers in invasive carcinoma. Whereas Aurora‐A/STK15 mRNA levels were similarly up‐regulated in dysplastic and invasive carcinoma cells (p = 0.0797), Survivin (p = 0.0046) and Cyclin‐D1 (p = 0.0017) mRNA levels increased from dysplastic to invasive carcinoma cells. In carcinomas, Incenp mRNA correlated with T category (p = 0.0149), and Survivin (p = 0.0382) and Cyclin‐D1 (p = 0.0185) were associated with tumour differentiation. Importantly, a significantly higher (p = 0.0419) fold‐change of Aurora‐A/STK15 mRNA (p = 0.0419), but not Incenp, Survivin, Mad‐2 or Cyclin‐D1, was observed in sCRC cases with CIN (n = 29) when compared with tumours showing microsatellite instability (MIN, n = 10). The present data are the first to show an early increase of the centrosomal kinase Aurora‐A/STK15 in the adenoma–carcinoma sequence of sCRC. The regulation of this kinase differs in CIN‐ and MIN‐type sCRCs and the pattern of changes is different from those of the cell‐cycle‐associated markers Survivin, Mad‐2, and Cyclin‐D1. This reinforces the concept of preferential dysregulation of the centrosome complex in CIN‐type (aneuploid), compared with MIN‐type, sporadic colorectal cancers and may influence the response to and efficiency of novel therapeutics targeting Aurora kinases. Copyright


Diagnostic Pathology | 2006

Grid technology in tissue-based diagnosis: fundamentals and potential developments.

Jürgen Görtler; Martin Berghoff; Gian Kayser; Klaus Kayser

Tissue-based diagnosis still remains the most reliable and specific diagnostic medical procedure. It is involved in all technological developments in medicine and biology and incorporates tools of quite different applications. These range from molecular genetics to image acquisition and recognition algorithms (for image analysis), or from tissue culture to electronic communication services.Grid technology seems to possess all features to efficiently target specific constellations of an individual patient in order to obtain a detailed and accurate diagnosis in providing all relevant information and references.Grid technology can be briefly explained by so-called nodes that are linked together and share certain communication rules in using open standards. The number of nodes can vary as well as their functionality, depending on the needs of a specific user at a given point in time. In the beginning of grid technology, the nodes were used as supercomputers in combining and enhancing the computation power. At present, at least five different Grid functions can be distinguished, that comprise 1) computation services, 2) data services, 3) application services, 4) information services, and 5) knowledge services.The general structures and functions of a Grid are described, and their potential implementation into virtual tissue-based diagnosis is analyzed. As a result Grid technology offers a new dimension to access distributed information and knowledge and to improving the quality in tissue-based diagnosis and therefore improving the medical quality.


Journal of Pathology Informatics | 2013

The history of pathology informatics: A global perspective

Seung Park; Anil V. Parwani; Raymond D. Aller; Lech Banach; Michael J. Becich; Stephan Borkenfeld; Alexis B. Carter; Bruce A. Friedman; Marcial Garcia Rojo; Andrew Georgiou; Gian Kayser; Klaus Kayser; Michael Legg; Christopher Naugler; Takashi Sawai; Hal Weiner; Dennis Winsten; Liron Pantanowitz

Pathology informatics has evolved to varying levels around the world. The history of pathology informatics in different countries is a tale with many dimensions. At first glance, it is the familiar story of individuals solving problems that arise in their clinical practice to enhance efficiency, better manage (e.g., digitize) laboratory information, as well as exploit emerging information technologies. Under the surface, however, lie powerful resource, regulatory, and societal forces that helped shape our discipline into what it is today. In this monograph, for the first time in the history of our discipline, we collectively perform a global review of the field of pathology informatics. In doing so, we illustrate how general far-reaching trends such as the advent of computers, the Internet and digital imaging have affected pathology informatics in the world at large. Major drivers in the field included the need for pathologists to comply with national standards for health information technology and telepathology applications to meet the scarcity of pathology services and trained people in certain countries. Following trials by a multitude of investigators, not all of them successful, it is apparent that innovation alone did not assure the success of many informatics tools and solutions. Common, ongoing barriers to the widespread adoption of informatics devices include poor information technology infrastructure in undeveloped areas, the cost of technology, and regulatory issues. This review offers a deeper understanding of how pathology informatics historically developed and provides insights into what the promising future might hold.

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Martin Werner

Technische Universität München

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Agnes Csanadi

University Medical Center Freiburg

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