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Featured researches published by Peter Buhtz.


American Journal of Pathology | 2004

Retention of the Arginine Allele in Codon 72 of the p53 Gene Correlates with Poor Apoptosis in Head and Neck Cancer

Regine Schneider-Stock; Christian Mawrin; Christiane Motsch; Carsten Boltze; Brigitte Peters; Roland Hartig; Peter Buhtz; Anja Giers; Astrid Rohrbeck; Bernd Freigang; Albert Roessner

The allele constitution at codon 72 of the p53 gene (CGC-arginine or CCC-proline) plays a major role in inducing apoptosis in p53 mutant cells. To verify this, we determined GC-status, p53-mutations, and p53-loss of heterozygosity (LOH) in a group of 54 squamous cell carcinomas of the head and neck (SCCHN). A novel approach, using a one-step real-time PCR analysis with fluorescent hybridization probes, was applied to detect the GC status in tumors and corresponding blood samples. p53 mutations in exons 4 to 8 were detected by PCR-SSCP-sequencing analysis. Apoptosis was determined immunohistochemically using antibodies against Fas, FasL, p53, Bcl2, and terminal deoxy-transferase-mediated dUTP nick end labeling (TUNEL) staining. The overall frequency of p53-LOH in SCCHN was 45.2%. In cases of LOH, there was a preferential loss of the proline allele, which was associated with an up-regulation of Bcl2 and lack of co-expression of Fas/FasL and, thus, impaired apoptosis (P < 0.001). Apoptosis was not observed in tumors carrying the arginine allele. p53 mutations were detected in 29.6% of SCCHN and preferentially occurred at the arginine allele (P = 0.01). p53 alterations were more frequently observed in tumors of the oral cavity, oropharynx and hypopharynx, whereas they were rare in larynx carcinomas (P = 0.07). The p53-LOH status was not found to be significantly correlated with sex, age, TNM-status, or tumor grading. We conclude that apoptosis is correlated with the allelic status of codon 72 in SCCHN. Homozygous proline 72 appears to be an important regulator of apoptosis via the Fas/FasL pathway in SCCHN.


Pathology Research and Practice | 2002

Prognostic value of MMP-2, -9 and TIMP-1,-2 immunoreactive protein at the invasive front in advanced head and neck squamous cell carcinomas.

Constanze Ondruschka; Peter Buhtz; Christiane Motsch; Bernd Freigang; Regine Schneider-Stock; Albert Roessner; Carsten Boltze

In head and neck cancer as well as in other carcinomas, tumor expansion and spread to distant sites require the secretion of destructive enzymes that degrade the extracellular matrix. A variety of proteases contribute to matrix destruction. Characteristics of the invasive tumor front may reflect tumor prognosis better than do other parts of the tumor. Therefore, it was the aim of the present study to (i) compare central and peripheral tumor zones for differences in the expression of matrix-metalloproteinases (MMP) -2 and -9 and their naturally occurring inhibitors (tissue inhibitor of matrix-metalloproteinases (TIMP) -1 and -2), (ii) examine the morphological potential of malignancy, and (iii) correlate these findings with clinicopathological parameters. The study population consisted of 106 surgical specimens of advanced head and neck squamous cell carcinomas. The invasive front was graded for malignancy, and immunohistochemical staining with MMP-2, MMP-9, TIMP-1 and TIMP-2 antibodies was performed. Both MMP-2 and MMP-9 were found to be significantly overexpressed at the tumor front. The MMP-2-positive invasive front exhibited diminished overall survival times. In multivariate analysis, MMP-2 expression retained its correlation with overall survival in addition to nodal status and total malignancy score. Expression of TIMP-2 correlated with local tumor invasion. We conclude that the expression of MMP-2 at the invasive front is a marker of poor survival and appears to be associated with early recurrence in initially lymph node-negative patients.


Pathology Research and Practice | 1998

ALVEOLAR SOFT PART SARCOMA OF THE UTERINE CORPUS: REPORT OF TWO CASES AND REVIEW OF THE LITERATURE

Kathrin Radig; Peter Buhtz; Albert Roessner

Alveolar soft-part sarcoma (ASPS) is a rare tumor of uncertain histogenesis, mainly localized in the extremities and less frequently found in the head, neck and trunk. The present report describes two cases of ASPS localized in the uterus. In general, this entity is very rarely encountered in the female genital tract. Including the two cases presented here, 27 patients have been described in the literature. Whereas the prognosis for ASPS in soft tissues is usually poor (most of the patients died of lung metastases), those localized in the female genital tract are associated with a much better survival. This could be explained by the fact that their diameter seldom exceeds 5 cm, the size which is regarded as being the critical prognostic limit. Histologically, both tumors showed the same characteristics as known for ASPS in other localizations: organoid or nest-like arrangement of tumor cells; rounded or polygonal cells with cytoplasm of varying density; thin-walled, sinusoidal vascular spaces between tumor cell nests. Immunohistochemically, we found positivity for desmin and, to a lesser extent, for vimentin. Cytokeratin was negative, which is important in differential diagnosis to other rare uterine neoplasias like clear cell (mesonephroid) adenocarcinomas or metastases.


Cell and Tissue Research | 2010

Synthesis and localization of trefoil factor family (TFF) peptides in the human urinary tract and TFF2 excretion into the urine

Margarita Rinnert; Margitta Hinz; Peter Buhtz; F. Reiher; Wolfgang Lessel; Werner Hoffmann

Trefoil factor family (TFF) peptides promote regeneration and repair processes of mucous epithelia. They also probably play a key role in the remarkable regenerative capacity of the urinary tract epithelia. We have localized TFF1, TFF2, and TFF3 expression systematically in surgical specimens from the urinary tract by reverse transcription with the polymerase chain reaction, Western blot analysis, and immunohistochemistry. Urine samples from patients suffering from nephrolithiasis have been investigated and compared with those of healthy controls. TFF synthesis is detectable along the entire urinary tract epithelia. TFF3 synthesis is the most pronounced followed by TFF1, whereas TFF2 synthesis is occasionally detectable but only in trace amounts. In contrast, TFF2 is the predominant TFF peptide excreted into the urine, and significantly increased urinary TFF2 levels (together with occasionally raised TFF3 levels) have been observed in patients suffering from nephrolithiasis. Thus, we consider that TFF3 plays a major part in regeneration and restitution processes in urinary tract epithelia. TFF2 and probably also TFF3 are candidate biomarkers for nephrolithiasis and possibly other inflammatory conditions of the urinary tract.


Oncogene | 2005

Promoter CpG hypermethylation and downregulation of DICE1 expression in prostate cancer

Albrecht Röpke; Peter Buhtz; Malte Böhm; Jeannette Seger; Ilse Wieland; Ernst P. Allhoff; Peter Wieacker

A critical region of loss of heterozygosity on human chromosome 13q14 harbors the tumor suppressor gene DICE1 (DDX26). To elucidate the reduced DICE1 expression in tumor cells, the putative promoter sequence upstream of the DICE1 gene was analysed. This sequence shows a high GC content and is rich in CpG sites and binding sites of transcriptional factors. Promoter activity was identified within three overlapping fragments of the 800 bp sequence upstream of the DICE1 gene. A 13 bp deletion polymorphism detected in the DICE1 promoter region showed a decreased activity compared with the undeleted variant. However, this 13 bp deletion was seen in male control samples and patients with prostate cancer or benign prostatic hyperplasia at similar rates. A reduced DICE1 expression was observed in prostate cancer cell lines DU145 and LNCaP. This downregulation is associated with hypermethylation of the DICE1 promoter. Treatment of both prostate cancer cell lines with 5-azacytidine leads to upregulation of DICE1 expression. Hypermethylation of CpG sites of the DICE1 promoter was observed in four of eight analysed prostate cancers. This study suggests that transcriptional repression of DICE1 is caused by hypermethylation of the DICE1 promoter region in prostate cancer cells.


Pathology International | 2004

Rhinoscleroma associated with Rosai–Dorfman reaction of regional lymph nodes

Hans-Udo Kasper; Veit Hegenbarth; Peter Buhtz

Rhinoscleroma is an uncommon chronic, destructive infection of the respiratory mucosa caused by Klebsiella rhinoscleromatis. This coccobacillus can be found in the typical histiocytes, the Mikulicz cells. Extranasal and nodal involvement in this disease is rare, but documented. Rosai–Dorfman disease or sinus histiocytosis with massive lymphadenopathy is also a rare, non‐hereditary disorder. Bilateral cervical lymphadenopathy with emperipolesis, as the main histological characteristic, is the most common presentation. It can also occur extranodally. We report a case of rhinoscleroma occurring in a 62‐year‐old woman since 1984, who developed parotid gland and lymph node involvement. The changes in the nasal mucosa and the parotid gland showed chronic inflammation with Mikulicz cells. In the lymph nodes, features characteristic of Rosai–Dorfman disease were seen. Taking into consideration the literature dealing with both of these diseases, we discuss that Rosai–Dorfman disease could be a special type of lymph node reaction and is not necessarily an entity of its own. Therefore, it should be known as Rosai–Dorfman lymph node reaction. Furthermore, there seems to be an interconnection between Rosai–Dorfman disease and rhinoscleroma.


Pathology Research and Practice | 1999

Hepatic angiomyolipoma in a 26-year-old Caucasian woman with a history of tibial osteosarcoma.

Christoph Röcken; Regine Schneider-Stock; Peter Buhtz; Thomas Manger; Albert Roessner

We report on a 26-year-old Caucasian woman who was referred to the Department of Surgery complaining of general malaise, feeling of fullness with occasional vomiting and intermittent jaundice. The patient had previously suffered from tibial osteosarcoma of the left leg which was resected 13 years ago and subsequently treated with radiation and chemotherapy. During clinical investigations a 12 x 12 x 6.5 cm large mass was found in the left lobe of the liver. This was resected, and subsequently shown to be a sporadic hepatic angiomyolipoma. In order to investigate a possible link between the two tumours, we investigated mutations in the p53-gene, loss of heterozygosity (LOH) at p53, Rb and p16, c-Myc expression, and the telomerase activity of the angiomyolipoma and the osteosarcoma. Whilst the tibial osteosarcoma showed LOH at p16, no genetic alterations or increased telomerase activity were found in the angiomyolipoma. The occurrence of both these tumours in this patient is therefore probably a coincidence.


Medizinische Klinik | 2002

Manifestation eines Cushing-Syndroms und osteoporotischer Frakturen in der Schwangerschaft einer Patientin mit Carney-Komplex

Kirsten Reschke; Silke Klose; Klaus Mohnike; Peter Buhtz; Albert Roessner; Hendrik Lehnert

ZusammenfassungAnamnese und klinischer Befund: Aufgrund von therapierefraktären Lendenwirbelsäulenbeschwerden wurde bein einer 31-jährigen Patientin nach einer Sectio caesarea eine Röntgenuntersuchung veranlasst, die Frakturen von L2 und L3 bei stark erhöhter Strahlentransparenz zeigte. Neben den klinischen Zeichen des Hypercortisolismus waren bei der Untersuchung auch zahlreiche Hyperpigmentationen im Gesichtsbereich unter Einbeziehung des Lippenrots und der rechten Konjunktiva auffällig, so dass ein Carney-Komplex vermutet wurde. Untersuchungen: Ein nicht supprimierbares Cortisol bestätigte in der endokrinologischen Diagnostik einen Hypercortisolismus. Die selektive Venenkatheteruntersuchung ergab den Verdacht auf eine bilaterale Cortisolmehrproduktion. Auch in der CT-Untersuchung der Nebennieren fanden sich knotige Veränderungen rechts und eine Hyperplasie links. Therapie und Verlauf: Bei der bilateralen Adrenalektomie konnte histologisch die Verdachtsdiagnose einer primär pigmentierten nodulären Hyperplasie bestätigt werden. Die Zeichen des Hypercortisolismus bildeten sich rasch zurück. Schlussfolgerung: Die Diagnose eines Cushing-Syndroms bei Carney-Komplex wurde bei unserer Patientin erst nach Beendigung der Schwangerschaft gestellt, obgleich die Zeichen des Hypercortisolismus schon lange vor Beginn der Schwangerschaft bestanden. An die seltene Diagnose eines Carney-Komplexes sollte bei klinischen Symptomen des Hypercortisolismus und charakteristischen phänotypischen Veränderungen (Hyperpigmentationen) gedacht werden.AbstractHistory and Clinical Findings: In a 31-year-old patient a conventional X-ray was performed due to persistend pain at the lumbar spine level after a cesarean section. It revealed compression fractures of L2 and L3. Besides very clear clinical signs of hypercortisolism, multiple hyperpigmentations and naevi in the patients face including the lips and the conjunctiva of the right eye were visible, suggesting a Carney complex. Investigations: Insuppressible cortisol levels confirmed an adrenal origin of hypercortisolism. A selective catheterization of adrenal veins supported the presence of bilateral adrenal cortisol production. The computed tomography showed nodular lesions in the right and a hyperplasia of the left adrenal gland. Treatment and Course: A bilateral adrenalectomy was performed and a primary pigmented nodular adrenal hyperplasia was confirmed histologically. Clinical signs of hypercortisolism rapidly resolved after adrenalectomy. Conclusions: The diagnosis of Cushings syndrome as a part of Carney complex was diagnosed at the end of a pregnancy although signs of hypercortisolism were present a long time before. The rare diagnosis of Carney complex should be considered in patients exhibiting symptoms of hypercortisolism and the typical clinical signs (hyperpigmentations).


The Journal of Urology | 2004

Extended radical lymphadenectomy in patients with urothelial bladder cancer: Results of a prospective multicenter study

Joachim Leissner; M.A. Ghoneim; H. Abol-Enein; J.W. Thüroff; L. Franzaring; M. Fisch; H. Schulze; G. Managadze; E. P. Allhoff; M.A. El-Baz; H. Kastendieck; Peter Buhtz; Siegfried Kropf; R. Hohenfellner; Helmut Wolf


The Prostate | 2004

Up-regulation of cathepsin X in prostate cancer and prostatic intraepithelial neoplasia

Dorit K. Nägler; Sabine Krüger; Angela Kellner; Edmund Ziomek; Robert Ménard; Peter Buhtz; Matthias Krams; Albert Roessner; Udo Kellner

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Albert Roessner

Otto-von-Guericke University Magdeburg

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Regine Schneider-Stock

University of Erlangen-Nuremberg

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Bernd Freigang

Otto-von-Guericke University Magdeburg

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Carsten Boltze

Otto-von-Guericke University Magdeburg

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Christiane Motsch

Otto-von-Guericke University Magdeburg

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Siegfried Kropf

Otto-von-Guericke University Magdeburg

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Angela Kellner

Otto-von-Guericke University Magdeburg

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