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L Riethdorf

Publications and source records attributed to L Riethdorf.

At least 37 records · Page 2Linked to original sources
PubMed1999

Strongly reduced expression of the cell cycle inhibitor p27 in endometrial neoplasia.

In the present study we investigated the expression of the cell cycle inhibitor p27 in endometrial neoplasia using immunohistochemistry with a p27-specific antibody. Expression of p27 in endometrial carcinomas was compared with expression in the normal endometrium throughout the cycle. Normal endometrial cells showed strong nuclear expression of p27. Expression was present throughout the cycle and was stronger during the secretory phase. We found strongly reduced or abolished expression of p27 in endometrial carcinoma (85.3% of cases). The 41 tumours analysed were classified according to p27 staining intensity and percentage of positive cells into the following categories of p27 expression: negative/very low (56.0%); low (29.3%); moderate (14.7%) and high (0.0%). All the p27-positive tumours were well-differentiated endometrioid carcinomas of malignancy grade G1. Comparison with the p53 status showed that all tumours with strong p53 expression had low/negative p27 staining, while those that were positive for p27 had negative/low p53 staining. Reduced or absent p27 levels were also observed by Western blot analysis both in tumour samples and in HEC-1B endometrial adenocarcinoma cells. It thus seems that p27 expression is essential for the control of normal endometrial proliferation, and reduced or absent p27 expression may be an important step in endometrial carcinogenesis.

Adenocarcinoma↗
PubMed1999

Matrix-metalloproteinases 1, 2, and 3 and their tissue inhibitors 1 and 2 in benign and malignant breast lesions: an in situ hybridization study.

Invasive growth requires degradation of extracellular matrix. Altered expression of matrix degrading enzymes may indicate an increased potential for invasive growth. We determined the expression patterns of matrix-metalloproteinases (MMP)-1, -2, and -3 and of the tissue inhibitors of metalloproteinases (TIMP)-1 and -2 by in situ hybridization with isotopically labeled RNA probes in normal breast tissue (n=6), fibrocystic disease (n=20), five cases of which contained radial scars, lobular carcinoma in situ (CLIS; n=5), ductal carcinoma in situ (DCIS; n=9) and invasive carcinomas (n=24). Only a few cells displayed MMP-1- and MMP-2-specific labeling in normal breast tissue and fibrocystic disease. Noninvasive ductal carcinomas showed elevated MMP-2 transcript levels in peritumor stromal cells in the absence of significant MMP-1 specific signals. In general, compared with adjacent normal breast tissue, a gradual increase of MMP-2 was found in noninvasive to invasive cancers. Invasive ductal and lobular carcinomas displayed co-expression of MMP-1 and MMP-2 by stromal cells, mainly of the invasion front, with high signal intensity particularly in high-grade invasive carcinomas. Tumor cells and peritumor stroma showed low MMP-3 transcript levels, especially in medullary carcinomas. TIMP-1 and -2 transcript levels were increased in invasive carcinomas correlating with the histological grade. These RNA expression patterns suggest an increased invasive potential in breast carcinomas even prior to histologically overt invasive growth.

Adenocarcinoma↗
PubMed1999

Relaxin-like factor (RLF): a new specific marker for Leydig cells in the ovary.

Relaxin-like factor (RLF), also known as the Leydig cell insulin-like factor (Ley-I-L), is a novel member of the insulin-IGF-relaxin family of hormones and growth factors that has recently been shown to be strongly expressed in testicular Leydig cells. Expression of the RLF peptide in the human ovary and in ovarian tumors has not been studied. In the present study, the expression of the RLF peptide in the human ovary was investigated by immunohistochemistry using a specific antibody raised against human RLF. By this method, RLF was found to be expressed in hilus (Leydig) cells and theca interna cells but absent in granulosa cells, ovarian stromal cells, and surface epithelium. RLF expression was also observed in the corpus luteum, although at a lower level than in theca cells. Thirty-seven sex cord-stromal tumors and five cases of hilar Leydig cell hyperplasia were also investigated for RLF expression. RLF was found to be strongly expressed in hilar Leydig cell hyperplasia and sex cord-stromal tumors with a component of Leydig or luteinized cells. Of the analyzed theca cell tumors, two displayed a diffuse staining pattern. As expected, RLF was not expressed in granulosa cell tumors. In conclusion, RLF appears to be a useful marker for Leydig cells in the human ovary and may be a diagnostic supplement in hyperplasias and tumors derived therefrom.

Biomarkers, Tumor↗
PubMed1998

[p53 mutations and HPV infections in squamous epithelial carcinomas of the head-neck region. Long-term follow-up].

Mutations of the p53 gene are the most commonly observed genetic alterations in malignant tumors and are often associated with a loss of the tumor suppressor function of the p53 protein. We have analyzed specimens of head and neck squamous cell carcinomas (HNSCC) from 110 patients for p53 gene mutations and 92 of them additionally for human papillomavirus (HPV) infection in order to evaluate the prognostic significance of these factors by comparison with clinical follow-up data. Using the method of polymerase chain reaction (PCR)/temperature gradient gel electrophoresis (TGGE), mutations within the exons 5 to 8 of the p53 gene were found in 48 tumors (44%). Sequencing revealed missense mutations in most cases (15/20). Frequency of p53 gene mutations was not related to the tumor stage, the grade of differentiation, the presence of lymph node metastases, or the smoking history of the patients. With the help of a highly sensitive PCR/hybridization assay, an infection with the high-risk HPV types 16 and 18 could be detected in 39/92 tumor specimens (42%). Follow-up data were obtained from 99 patients with a range of 2-112 months. No correlation of overall survival on the presence of p53 gene mutations or HPV infection could be observed. The absence of statistically significant correlations between p53 gene mutations and progressive disease, however, does not exclude its putative relevance in early phases of tumor development.

Adult↗
PubMed1998

Expression of the MCP-1 gene and the HPV 16 E6/E7 oncogenes in squamous cell carcinomas of the cervix uteri and metastases.

Monocyte chemoattractant protein 1 (MCP-1) plays an important role in the recruitment of monocytes in solid tumors. Previously, for cervical carcinoma cell lines an inverse correlation between the expression of the MCP-1 gene and the human papillomavirus (HPV) oncogenes E6/E7 was described. In this study paraffin-embedded biopsy specimens from 25 squamous cell carcinomas of the cervix uteri were analyzed for the expression of the MCP-1 gene and the HPV 16 E6/E7 oncogenes by RNA/RNA in situ hybridization. Similar to in vitro analyses, in our material a negative correlation between the transcription of these genes in tumor cells could be demonstrated in 19/25 cases, whereas in 6 cases both MCP-1 gene and HPV oncogene transcription could be detected. Interestingly, the same results regarding MCP-1 gene and HPV oncogene expression were observed in the majority of corresponding metastases. On the other hand, in stromal cells MCP-1-specific transcripts could be detected in all cases. In most of them intra- and/or peritumoral macrophages were observed. Our findings support the hypothesis that HPV oncoproteins are negative regulators of MCP-1 transcription.

Carcinoma, Squamous Cell↗
PubMed1998

Dysregulated expression of CD66a (BGP, C-CAM), an adhesion molecule of the CEA family, in endometrial cancer.

CD66a (BGP, C-CAM) is an adhesion molecule of the carcinoembryonic antigen family that has been shown to be down-regulated in colorectal, prostate, and breast cancers. The purpose of the present study was to determine its expression pattern in the normal human endometrium and in endometrial neoplasia. For this purpose, we performed immunohistochemistry using the 4D1/C2 monoclonal antibody on a series of 24 normal endometrial samples and 47 endometrial carcinomas. Strong CD66a expression was observed in glandular and luminal epithelial cells of the normal endometrium with a consistent localization at the apical poles of these cells throughout the cycle. In late secretory (premenstrual) phase, loss of cellular polarity resulted in a membranous expression pattern in some glandular cells. In the analyzed tumor samples increasing areas with a complete loss of expression were observed with increasing malignancy grade. The apical expression pattern of the normal epithelium was changed to a membranous all-around pattern in 55% of the tumors, mostly in solid areas. This change correlated with malignancy grade and could be observed in 3 of 15 G1 tumors, 4 of 12 G2 tumors, 11 of 12 G3 tumors, and 8 of 8 serous-papillary carcinomas. Areas with membranous expression pattern could be observed along with areas with a normal apical expression pattern in lower grade carcinomas and with areas with complete loss of expression in high grade tumors. Northern blot analysis showed a loss of mRNA expression in tumor samples and HEC-1B endometrial adenocarcinoma cells. Loss of protein expression in the tumor samples was also observed by Western blot. In conclusion, CD66a protein expression is dysregulated in endometrial carcinomas, showing reduction or loss of expression with increasing malignancy grade and a change from the apical to a membranous localization.

Antigens, CD↗
PubMed1997

Molecular and immunohistochemical analysis of p53 mutations in scrapings and tissue from preinvasive and invasive breast cancer.

Mutations of the p53 gene appear to be one of the most common abnormalities in human cancer. Although many studies have been published about p53 alterations in breast cancer, data on molecular biological detection of p53 mutations in in situ lesions are still rare, and the implications for breast cancerogenesis are unclear. Tissue samples from 83 patients with different stages of breast cancer and from 13 patients with benign breast lesions were screened for p53 gene mutations by polymerase chain reaction (PCR) followed by temperature-gradient gel electrophoresis (TGGE). p53 protein accumulation was analysed by immunohistochemistry (IHC). Samples were gained from fresh-frozen tissue, scrapings, or paraffin embedded tissue. Additionally, 23 pairs of primary tumours and corresponding lymph nodes were examined. p53 gene aberrations were found in 55.7% of the infiltrating carcinomas, in 31.5% of the ductal carcinomas in situ (DCIS) and in one atypical ductal hyperplasia. A positive correlation was seen with high-grade tumours and with comedo. There was no statistically significant relationship with respect to age, menopausal status, tumour size, hormone receptor status or lymphatic invasion. Concordance between TGGE and IHC was seen in only 63% of the cases analysed. However, with regard to p53 mutation screening by TGGE, a high significance (P = 0.0008) was seen between standard tissue extraction and our scrape preparation technique. Among 8 pairs of primary tumours and their corresponding lymph node metastases, only 3 harbored identical p53 mutations in the same exon, while in 5 cases with mutant p53 in the primaries, no mutation was seen in the lymph node. Our data indicate that p53 mutations are frequent in breast tumours associated with unfavorable prognosis, including high-grade or the comedo histotype. There is evidence that p53 gene alterations occur early in breast cancerogenesis, as mutations were detected not only in in situ carcinomas but also in atypical ductal hyperplasia.

Adult↗
PubMed1997

p53 gene mutations and HPV infection in primary head and neck squamous cell carcinomas do not correlate with overall survival: a long-term follow-up study.

We analyzed specimens of head and neck squamous cell carcinomas (HNSCC) from 110 patients for p53 gene mutations, and 92 of them for human papillomavirus (HPV) infection, in order to evaluate the prognostic significance of these factors by comparison with clinical follow-up data. Mutations within the exons 5 to 8 of the p53 gene were found in 48 tumors (44%). Sequencing revealed in most cases mis-sense mutations (16/21). Frequency of p53 gene mutations was not related to the tumor stage or the presence of lymph node metastases. Of the 46 tumors that were analyzed by immunohistochemistry, 26 stained positively (56%). The number of positively stained nuclei increased slightly with decreasing differentiation of the tumors, whereas no correlation was found between tumor stage and immunoreactivity. An infection with the high-risk HPV types 16 and 18 could be detected in 39/92 tumor specimens (42%). Follow-up data were obtained from 99 patients within a range of 2 to 112 months. No dependence of overall survival on the presence of p53 gene mutations or HPV infection could be observed. The absence of statistically significant correlations between p53 gene mutation and progressive disease, however, does not deny its putative relevance in early phases of tumor development.

Adult↗
PubMed1997

Differential expression of CD66a (BGP), a cell adhesion molecule of the carcinoembryonic antigen family, in benign, premalignant, and malignant lesions of the human mammary gland.

CD66a, also known as biliary glycoprotein (BGP), is a member of the carcinoembryonic antigen (CEA) family and the human homologue of the rat cell-CAM. There is evidence that aberrant expression or loss of CD66a in tumor tissue is of biological significance. No data about its expression in breast carcinoma cells and only sparse information about the expression of CD66a in normal breast are available thus far. In this study we used monoclonal antibodies to analyze the expression of CD66a and CEA in normal tissue, benign lesions, and in noninvasive and invasive carcinomas of the mammary gland. In normal tissue and benign lesions, CD66a was consistently expressed at the apical sites of epithelial cells and in myoepithelia, whereas CEA was absent or was restricted only to some apical membranes within the ductal tree. The specific staining of myoepithelia was most evident in pseudoinfiltrative radial scars and sclerosing adenosis. However, the apical expression of CD66a disappeared with the development of the malignant phenotype in noninvasive and invasive carcinomas, and changed gradually from low- to high-grade noninvasive carcinomas into a predominant uniform membrane staining all around the atypical cells. CEA expression was irregular in intensity and distribution. The native apical CD66a staining was partially preserved in some highly differentiated invasive carcinomas with a better prognosis, such as tubular and papillary carcinomas. These findings indicate that loss of CD66a expression rather than a change in staining patterns coincides with the development of the malignant phenotype.

Antibodies, Monoclonal↗
PubMed1996

Comparison of benign and malignant endometrial lesions for their p53 state, using immunohistochemistry and temperature-gradient gel electrophoresis.

The aim of this study was to evaluate the presence and distribution of p53 alterations in pure endometrioid adenocarcinomas (n = 120) of different grades and stages, as opposed to normal endometrium (n = 13) and various risk groups of hyperplasia (n = 39). All samples were initially analysed by immunohistochemistry with the monoclonal antibody Ab-6. Normal endometria were negative. With increasing degrees of malignancy, the number of cases with p53 accumulation rose and ranged from 9% to 18% in hyperplasia, through 25% in low-grade carcinomas (G1), to 69% in high-grade carcinomas (G3). This increase was also seen when comparing tumours by stage. Of carcinomas in stage IA, only 17% showed p53 immunostaining, in contrast with 72% in stage IC. Of this material, 34 carcinomas and 8 hyperplasias were analysed for p53 mutations in exons 5-8 by means of polymerase chain reaction and temperature-gradient gel electrophoresis (TGGE). In none of 5 hyperplasia and 6 of 12 carcinomas showing p53 accumulation by immunohistochemistry, p53 mutations were detected by TGGE. In contrast, 4 of 22 carcinomas harboured mutant p53 but were negative by immunohistochemistry. Immunohistochemical and molecular investigations revealed that p53 alterations are related to the standard prognostic markers of endometrial cancer, i.e. grading and staging. TGGE, an indirect screening procedure for p53 mutations, is used to detect the type of p53 alteration and may provide additional insight into the complex figure of p53 abnormalities in the development and progression of malignant endometrial lesions.

Adult↗
PubMed1996

[Proliferating leiomyoma after hysteroscopic myoma resection].

A proliferative leiomyoma, which had possibly been removed only subtotally by hysteroscopic resection, grew postoperatively so that vaginal hysterectomy had to be carried out. The histology of the leiomyoma showed an increased expression of the proliferative marker Ki-67.

Adult↗
PubMed1996

Differential expression of the monocyte chemoattractant protein-1 gene in human papillomavirus-16-infected squamous intraepithelial lesions and squamous cell carcinomas of the cervix uteri.

Monocyte chemoattractant protein (MCP)-1 is an important factor involved in the cross-talk between mononuclear cells and human papilloma-virus (HPV)-infected cervical epithelia. To prove the experimental model of a negative regulatory loop between the expression of the HPV oncogenes E6/E7 and the MCP-1 gene in vivo, we examined HPV-16-infected conization/hysterectomy specimens consisting of 6 low- and 6 high-grade squamous intraepithelial lesions (SILs) and 5 squamous cell carcinomas (SCCs) as well as the adjacent mucosa by isotopic RNA in situ hybridization. Langerhans cells and stromal macrophages were identified by the antibodies S-100 and PG-M1. E6/E7 expression was restricted to dysplastic or neoplastic keratinocytes, whereas MCP-1 transcripts were detectable in normal, dysplastic, and neoplastic epithelia, in endothelia, and in stromal macrophages. Langerhans cells were always negative. MCP-1 expression was predominant at the epithelial-mesenchymal junctions and especially intense when the stromal macrophage reaction was increased. Generally, the synchronous expression of E6/E7 and MCP-1 was very rare in SILs (2 of 12 cases). In high-grade SIL, MCP-1 expression was observed in 1 of 6 cases, whereas all lesions strongly hybridized with E6/E7 probes. In contrast, 4 of 5 SCCs re-expressed MCP-1, and 2 cases revealed marked transcriptional activities for both E6/E7 and MCP-1. Although preliminary, our observations lend support to the suggestion that the experimental model of transcriptional regulation and exclusion of either HPV E6/E7 or MCP-1 expression is especially pertinent to high-grade SIL, whereas in most SCCs, other environmental factors may influence this relationship.

Base Sequence↗
PubMed1993

[Mesenchymal chondrosarcoma of the maxilla].

Mesenchymal chondrosarcoma is a variant that shows some peculiarities in comparison with classical chondrosarcomas. On the basis of a case report on a young man with a mesenchymal chondrosarcoma of the maxilla, the clinical symptomatology and diagnostics, morphological findings and actual therapy are discussed. In addition, problems of differential diagnosis are also discussed.

Adult↗
PubMed1993

[Oral methotrexate in trophoblast seeding after laparoscopically treated tubal pregnancy].

The atypical course after laparoscopic conservative treatment of tubal pregnancy is described. Routine measurements of the serum HCG levels postoperatively showed, after a short period of decreasing HCG levels, a new increase of HCG values. Under the suspicion of a disseminated intraperitoneal trophoblastic tissue the patient was treated with 20 mg methotrexate q.i.d. per os for 5 days, as a result of which HCG levels returned to normal within a short time.

Adult↗
PubMed1991

[Alcoholic encephalopathies in autopsy material].

A report is given on incidence, complications, causes of death, and morphological diagnosis of chronic alcoholism in autopsy material. Chronic alcoholism was registered in 8.4% of all autopsies. The average age at death of alcoholics, particularly female, was significantly lower than that of all autopsy material. Pneumonia was the most frequent direct cause of death (21.1%). Acute ethanol intoxication was in second position (15.8%). Wernicke's encephalopathy was observed in 0.6% of all autopsies (18% of alcoholics), cerebellar atrophy occurred in 0.4% (12%), and central pontine myelinolysis was found in 0.2% (7%). The mean brain weight of alcoholics was 1310 g as compared with 1400 g of controls. Problems of clinical and postmortal diagnosis as well as medical and social consequences are discussed.

Adult↗