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Martin Werner

Publications and source records attributed to Martin Werner.

45 records · Page 3Linked to original sources
PubMed2002

Quantification of CK20 gene and protein expression in colorectal cancer by RT-PCR and immunohistochemistry reveals inter- and intratumour heterogeneity.

Cytokeratin 20 (CK20) is an epithelial protein expressed almost exclusively in the gastrointestinal (GI) tract and is widely used as immunohistochemical marker for routine diagnosis. In contrast, CK20 gene expression is not an established marker for the classification of tumours and the detection of disseminated cancer cells in colorectal cancer. Recently, real-time reverse transcriptase polymerase chain reaction (RT-PCR) has provided the means for reproducible and quantitative investigation of molecular markers. This report directly compares CK20 mRNA and protein expression in serial sections of archival, formalin-fixed, paraffin-embedded (FFPE) colorectal adenocarcinomas. CK20 expression was detected by immunohistochemistry (IHC) in 60/63 (95.2%) cases, by conventional RT-PCR in 58/60 (96.7%) and by quantitative RT-PCR using the LightCycler (LightCycler is a trademark of a Member of the Roche Group) System in 29/32 (90.6%) microdissected cases, one case yielding variable results. Despite the high detection rate of all three techniques, marked heterogeneity of CK20 expression was seen between different cases and also within individual cases. CK20 expression profiles were not related to particular histopathological features of the tumours. A good correlation (r = 0.8964) was found between CK20 mRNA and protein expression by comparing quantitative RT-PCR with IHC in 32 cases. This was also true for selected heterogeneous tumour cells within individual cases. Both RT-PCR and IHC are therefore valuable tools for CK20 detection in colorectal adenocarcinoma, with real-time RT-PCR providing supplementary quantitative information. This suggests a promising supportive role for quantitative RT-PCR in molecular pathology.

Adenocarcinoma↗
PubMed2002

Age and gender in the management of HIV-relevant sexual risks: theoretical background and first results of a population survey in the German speaking part of Switzerland.

OBJECTIVES: Health related lifestyles can be seen as resources for preventive behaviour in HIV-relevant situations. A concept was developed to analyse the management of HIV-relevant sexual risks and to uncover patterns of sexual lifestyles. In this paper first descriptive results will be presented focusing on gender and age. METHODS: 2,275 men and women between the ages of 19 and 65 from the German speaking part of Switzerland were interviewed in a computer-assisted telephone survey. Data were collected concerning attitudes, behaviours and resources, situational aspects and communication with regard to health and sexuality. Particularly, respondents were asked whether within the past 24 months they had had either first sexual contacts with new partners or casual sex, two forms of contacts which have special HIV relevance. RESULTS: 527 men and women reported having had first or casual sexual contacts. First results show a substantial lack of condom use among persons of both sexes in the age group older than 45. In general men showed more risk behaviour than women. CONCLUSIONS: For the first time in Switzerland, detailed data were collected from persons older than 45 years regarding sexual risk behaviour. Older, sexually active people are a vulnerable target group which has been neglected thus far in terms of research and preventive measures.

Adult↗
PubMed2002

Oligoclonality of a "composite" gastric diffuse large B-cell lymphoma with areas of marginal zone B-cell lymphoma of the mucosa-associated lymphoid tissue type.

We analyzed a case of oligoclonal Helicobacter pylori-associated, primary gastric diffuse large B-cell lymphoma (DLBCL) with areas of extranodal marginal zone B-cell lymphoma (MZBL) of mucosa-associated lymphoid tissue (MALT) type in a 61-year-old male patient. The patient had two separate tumors, in the corpus and in the antrum, each showing two morphologically distinct components (DLBCL and MZBL of MALT type). To determine the clonal relationship between the large- and small-cell components, we microdissected four samples from morphologically distinct tumor components at both tumor sites. PCR analysis revealed rearranged immunoglobulin heavy chain (IgH) genes of different sizes in three of the four microdissected samples. Cloning and sequencing of the PCR products displayed different IgH gene rearrangements in the two small cell components of the antrum and the corpus. A third genuinely differently rearranged IgH gene was found in the large-cell components of both antrum and corpus. Our results suggest that in primary gastric DLBCL with areas of MZBL of MALT type, the small-cell component may comprise more than one tumor clone. Furthermore, the large-cell component may evolve independently from coexisting MZBL.

Amino Acid Sequence↗
PubMed2002

Genetic alterations in presumptive precursor lesions of breast carcinomas.

The hypothetical multistep model of breast carcinogenesis suggests a transition from normal epithelium to invasive carcinoma via intraductal hyperplasia (without and with atypia) and in situ carcinoma. These presumptive precursor lesions are currently defined by their histological features, and their prognosis is imprecisely estimated from indirect epidemiological evidence. Cytogenetic and molecular-genetic analysis of these lesions give evidence for an accumulation of various genetic alterations during breast tumorigenesis. Using immuno-histochemistry overexpression of the c-erbB-2 oncogene was found in ductal carcinoma in situ (DCIS), but not in atypical intraductal hyperplasia (AIDH) and intraductal hyperplasia (IDH). An expression of mutant p53 tumor suppressor gene as well as expression of cyclin D1 was identified in DCIS. In IDH lesions loss of heterozygosity (LOH) at various loci could be identified, and comparative genomic hybridization (CGH) and fluorescence in situ hybridization (FISH) studies delivered evidence for DNA amplification on chromosomal region 20q13 in the early stage of IDH.However, little is currently known about genetic alterations in those premalignant lesions, and the chronology of genetic alterations and histopathological changes during carcinogenesis is mainly undiscovered.

Breast Neoplasms↗
PubMed2002

Chromosomal imbalances are associated with metastasis-free survival in breast cancer patients.

Multiple chromosomal imbalances have been identified in breast cancer using comparative genomic hybridization (CGH). Their association with the primary tumors' potential for building distant metastases is unknown. In this study we have investigated 39 invasive breast carcinomas with a mean follow-up period of 99 months (max. 193 months) by CGH to determine the prognostic value of chromosomal gains and losses. The mean number of chromosomal imbalances per tumor was 6.5+/-0.7 (range 2 to 18). The most frequent alterations identified in more than 1/3 of cases were gains on chromosomes 11q13, 12q24, 16, 17, and 20q, and losses on 2q and 13q. A significantly different frequency of chromosomal aberrations (p<or=0.05) was found between DNA-diploid and non-diploid tumors (gain on chromosome 17). Differences were also noted between tumors progressing to distant metastases within the period of follow-up and those which do not (gains on 11q13 and 12q24; loss on 12q). Significant univariate correlations (p<or=0.05) with the metastasis-free survival of patients were found for lymph node status, the cytometrical determined DNA ploidy (diploid/non-diploid) and anisokaryosis, and for DNA gains on 11q13, 12q24, 17, and 18p. An unexpected inverse correlation was found between clinical outcome and gains on 11q13 and 12q24. In multivariate analysis independent prognostic value, in addition to lymph node status, was found for chromosomal gains on 11q13, 12q24, 17 and 18p. Amplification on 20q, which did not correlate with metastasis-free survival in a univariate analysis, showed weak prognostic significance in combination with the nodal status. The prognostic value of chromosomal alterations - some of them by inverse correlation - suggests an interaction and/or compensation of the involved amplified genes and their effects on the occurrence of distant metastases in breast cancer patients.

Breast Neoplasms↗
PubMed2002

Cellular composition of stent-penetrating tissue.

BACKGROUND: A surprisingly low number (< 20%) of relevant (> 75%) restenoses occur in exophytic lesions after treatment with uncovered metal stents. The goal of this study was to investigate whether radial stent forces can exert localized influence on tumor growth. PATIENTS AND METHODS: In 17 patients, intraluminal tumor tissue was histologically investigated before and 1 week after stent implantation. The amount of intact tumor cells (ITCs) was compared to necrotic and nontumor cells. The result in patency was proved by fiberoptic bronchoscopy. RESULTS: Initially, stenoses in all patients were > 75%. Before stent implantation, biopsy samples in seven patients showed > 67% ITCs, and five patients had 34 to 67% ITCs. Five patients had 1 to 33% ITCs, and no patients had 0% ITCs. One week after stent implantation, the cellular aspect of the biopsy samples had changed significantly (p < 0.03): two patients had > 67% ITCs, one patient had 34 to 67% ITCs, and seven patients had 1 to 33% ITCs. Seven patients had no ITCs at all. Endoscopically, patency increased significantly (prestent, 10 +/- 14.1%; poststent, 90.6 +/- 14.3% [mean +/- SD]; p < 0.0001). CONCLUSION: Pressure exerted by the stent on adjacent tumor tissue may cause a profound reduction in the amount of ITCs, most probably caused by radial and shear stress forces that compromise blood supply and nutrients of the tumor stroma.

Aged↗
PubMedDate not supplied

Intraoperative examination of sentinel lymph nodes by ultrarapid immunohistochemistry.

The recently developed method of ultrarapid immunohistochemistry (IHC) was applied to the intraoperative examination of sentinel lymph nodes (SLNs) in breast cancer patients. In a prospective study of 50 patients with invasive breast carcinomas, a total of 60 SLNs were studied. Among them, 33 SLNs from 30 patients were studied intraoperatively using a direct immunoperoxidase method with anticytokeratin antibody clone MNF116. This technique has a turnaround time of less than 20 minutes. Ultrarapid IHC revealed 15 positive SLNs compared to 14 positive SLNs using hematoxylin and eosin (H and E) frozen sections. The one SLN missed in H and E frozen sections presented with cytokeratin-positive isolated tumor cells in the lymph node sinus. After paraffin embedding, H and E-stained serial step sections of the SLN specimens detected another two patients with isolated tumor cells. We also examined the remaining axillary lymph nodes (ALNs) by H and E-stained serial step paraffin sections. From 17 of the 30 patients with positive SLNs, 6 patients also had metastatic involvement of the ALNs of level I or II. Thus ultrarapid IHC was a very sensitive and rapid technique for the intraoperative detection of metastatic involvement of SLNs in breast cancer patients. This technique may be a useful complementary tool for the intraoperative study of SLNs, particularly in tumors that are a diagnostic challenge, such as lobular carcinoma.

Adult↗
PubMedDate not supplied

Transport and metabolism of gibberellins in relation to flower bud differentiation in Norway spruce (Picea abies).

A mixture of tritiated and deuterated gibberellin A(4) (GA(4)) was injected into the xylem of Norway spruce (Picea abies (L.) Karst) propagules, below an elongating shoot, or applied directly on the needles of an elongating shoot. The distribution of [(2)H(2)]GA(4) and [(3)H]GA(4) in the needles, stems and buds was determined after 4, 12 and 24 h. After 4 h, most of the xylem-injected GA(4) was found in the needles, whereas after 24 h, most of the GA(4) was found in the stem, with a small portion in the lateral buds. Of the GA(4) applied to the needles, 51% of the radioactivity recovered after 24 h was found in the stem and 2% in the lateral buds. Mixtures of tritiated and deuterated GA(4) and GA(9) were injected into elongating shoots of one abundant-flowering family and one limited-flowering family, grown either under conditions inductive for flowering (hot and dry, HD) or under noninductive conditions for flowering (cool and wet, CW). Shoots of both CW- and HD-treated propagules converted [(2)H(2)]GA(9) to [(2)H(2)]GA(51), [(2)H(2)]GA(4), [(2)H(2)]GA(34) and [(2)H(2)]GA(1), whereas [(2)H(2)]GA(4) was converted to [(2)H(2)]GA(34), [(2)H(2)]GA(1) and [(2)H(2)]GA(8). In shoots of both CW-treated clones, the main metabolite of [(3)H]GA(9) was in the GA(51) region. The HD-treated propagules converted more [(3)H]GA(9) to putative GA(4) than the CW-treated propagules. The main metabolite of [(3)H]GA(4) was in the GA(34) region. Radioactive metabolites were also found in the GA(1) and GA(8) regions.

Journal Article↗