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G Feil

Publications and source records attributed to G Feil.

32 records · Page 2Linked to original sources

The molecular basis of the antigenic variation of foot-and-mouth disease virus.

We have cloned and sequenced the viral protein (VP1)-coding regions of two foot-and-mouth disease virus (FMDV) serotypes (C1 and A5). Comparison of the derived amino acid sequences with the known VP1 sequence of FMDV O1K and the two FMDV A subtypes A10 and A12 shows two highly variable regions in the protein, at positions 40-60 and 130-160, as possible antigenic sites. In both variable regions, several sites could be detected where all three sequences of the A subtypes are identical but the three types A, C and O differ from each other. The second variable region overlaps with a major immunogenic determinant of the virus.

Amino Acid Sequence↗

Loss of chromosomes in clear cell renal cell carcinoma and in corresponding renal parenchyma.

Chromosome studies were done on six renal cell carcinomas (RCC) and on the corresponding renal parenchymas of the tumor bearing kidneys. Histopathologically, all tumors belonged to the clear cell subtype. All examined parenchymas were pathologically benign. None of the tumor cells showed the typical chromosomal aberrations described for (nonpapillary) RCC, i.e. deletions in the short arm of chromosome #3, or gains in the long arm of chromosome #5. In our series both the tumor and the benign kidney tissues were characterized by loss of chromosomes, especially of the chromosomes #6, #9, #16, #20, and of the Y chromosome. Trisomy of chromosome #7 was found frequently in benign parenchyma cells. The identical chromosomal changes in the tumor and in the parenchyma tissues might reflect rather in vivo mosaics rather than primary chromosomal aberrations in the oncogenetic process of clear cell RCC.

Adenocarcinoma, Clear Cell↗

DNA cytophotometry in renal cell carcinoma: a significant prognostic factor?

We report on a prospective DNA cytophotometric study of 66 patients with renal tumors, 61 of whom had renal cell carcinoma (RCC) (pT1-pT4, G1-G3). 16 of the patients had a metastasis at the time of diagnosis. Cell material from 1-5 specimens of each tumor was analyzed for intratumoral heterogeneity. The aim of the study was to evaluate the prognostic value of the following DNA parameters: DNA ploidy, DNA grade of malignancy (DNA MG), mean DNA, DNA index, 2c deviation index (2cDI), and 5c exceeding rate (5cER). In this study 21% of the tumors were non-aneuploid, 79% were aneuploid; however, it proved possible to diagnose 38% of the total collective as aneuploid only by analyzing several tumor areas. In five of 61 RCC patients who died during an observation period of 42 months, at least one area of the primary tumor was aneuploid. Aneuploid primary tumors also accompanied the development of metastases and recurrent tumors in four of the 61 RCC patients. Only DNA 2cDI was found to have a significantly positive clinical correlation with metastasis (r = 0.261) during the clinical course. This was not true, however, for the histopathologic parameters. Significantly positive correlations were found between the tumor stages and the following DNA parameters: mean DNA, DNA index, and 5cER. Histopathologic tumor grading showed a significantly positive correlation with DNA MG, mean DNA, and 5cER. Statistically, the mean values of all evaluated parameters were significantly higher in metastasizing and recurrent RCCs than in non-metastasizing carcinomas (p < 0.05; t-test). DNA cytophotometry cannot substitute histopathologic prognosis. However, the analysis of various DNA parameters helps considerably in evaluating both the malignant potential of kidney tumors and the benign parenchyma of tumor-bearing kidneys.

Adult↗

Renal cell carcinoma: immunohistological investigation of expression of the integrin alpha v beta 3.

alpha v beta 3 Integrin has been shown in various tumor entities to promote binding to superficial structures of the basement membrane during metastasis. The goal of the present paper was a structural demonstration of this Integrin in renal cell carcinoma (RCC). After removal of paraffin from formalin-fixed tissue, the cells were labelled with the antibody (VNR 147, H. Biermann, Bad Nauheim) using the peroxidase-antiperoxidase method (DAKO Diagnostical GmbH, Hamburg). Evaluation was carried out microscopically and semiquantitatively from missing (-) through moderate (+) to strong (+2) staining. A total of n = 79 RCCs and n = 53 healthy areas were examined. Semiquantitative staining results: there was a grading-dependent increase (+2) of stainability and thus alpha v beta 3 expression. Two of 53 benign specimens showed strong staining, 11 of 53, only weak staining. Four of 18 G1 RCCs showed strong staining, 11 of 18 only weak staining. Results for G2-RCCs: 11 with strong staining, 21 of 40 with weak staining. G3-RCCs: 4 with strong staining, 2 of 7 with weak staining. Of the metastases, on the other hand, 2 of 14 showed strong staining, another 8 of 14 only weak staining. There were no deviations within the histologic (clear-cell, chromophil, or chromophobe) subpopulations. This grading-dependent expression permits the conclusion that the probability of binding to the human basement membrane mediated by alpha v beta 3 Integrin rises with increasing grading, but the already metastatic cell exhibited this Integrin less strongly, since a basement membrane adhesion is no longer necessary for this cell group.

Carcinoma, Renal Cell↗

Renal cell carcinoma: relevance of angiogenetic factors.

Angiogenesis is essential for tumour growth. Mostly hypervasculariced renal cell carcinoma (RCC) usually express angiogenic factors, e.g. basic fibroblast factor (bFGF), vascular endothelial growth factor, and angiogenin (ag). This study was designed to evaluate the improvement of serological angiogenesis-factors, their prognostic relevance and correlation to tumour-grade, -stage and -volume. Measurement of bFGF, vEGF and ag was done with ELISA (Quantikine), R and D-Systems Europe Abbington, United Kingdom. The control group comprised 39 healthy blood donors, RCC-group were 35 patients with different RCC. Survival dates were presented with Kaplan-Meyer-curves, significance was tested with students-t-test. For all angiogenic factors a highly significant difference between the healthy and RCC-group was found. A strong correlation between angiogenic factors and tumor grade, -stage and -volume, was not found, but a trend for each of the angiogenic factors to correlate with grade was seen. No survival benefit was seen between patients with normal angiogenic factor over those with elevated angiogenic levels.

Adult↗

Control of hepatic parameters in renal cell carcinoma (RCC) by interleukin-6 (IL-6)?

RCC can go hand-in-hand with an elevation of various hepatic proteins. An interrelationship between the IL-6 titer, C-reactive protein (CRP) and the blood sedimentation rate (BSR) has already been proven. The aim of the present study was to study 1) the possibility of differentiating between healthy and RCC patients via IL-6 in the serum and 2) the relationship of IL-6 to hepatic parameters {alkaline phosphatase (AP), gamma-glutamyltransferase (gGT), serum proteins (E'p)} and the usual clinical prognostic parameters (tumor grading, staging). Serum analysis of 38 healthy patients via ELISA (DPC-Biermann, Germany) showed normal values of 1.2 ng/ml for IL-6, with a standards deviation of +/- 1.7 and a peak concentration of 3 ng/ml (specificity: 95%). In 20 RCCs there were IL-6 titers of 10.7 ng/ml +/- 6.56 in the pre-operative serum. The sensitivity of IL-6 was about 90%. The difference was statistically significant (p < 0.0001, Wilcoxon test). For IL-6 there was a positive correlation with the BSR (1-hour value: r = 0.7; 2-hour value: r = 0.6), CRP (r = 0.85), E'p (r = 0.6), and gGT (r = 0.6). No correlation was found between AP, the Robson stage, grading, and IL-6. IL-6 is potentially suitable for differentiating between healthy and RCC patients but is not tumor specific. IL-6 has a strong correlation with all laboratory values which were analyzed except AP thus there is considerable evidence for a cytokine (IL-6) control of the hepatic changes. Since some of the above-named laboratory parameters have prognostic relevance, IL-6 can be regarded as a cumulative prognostic parameter.

Alkaline Phosphatase↗

Marker for renal cell carcinoma (RCC): the dimeric form of pyruvate kinase type M2 (Tu M2-PK).

OBJECTIVE: The evaluate a potential tumor marker for RCC. Tumor formation is generally linked to an expansion of glycolytic phosphometabolite pools and aerobic glycolyticflux rates. To achieve this, tumor cells generally overexpress a special glycolytic isoenzyme, termed pyruvate kinase type M2. To establish the expansion of phosphometabolite pools pyruvate kinase switches between a tetrameric form with high phosphoenol-pyruvate (PEP) affinity and a dimeric form with a lower PEP affinity. The dimeric form is predominant in all tumors that have been investigated and has been termed TuM2Pk. MATERIALS AND METHODS: We studied: a) the expression of TuM2Pk in RCC by immunohistochemistry using a monoclonal antibody recognizing only the mono- or dimeric form of pyruvate kinase, b) the stability of TuM2Pk in serum by measuring TuM2Pk in 3 patients at different times after taking blood with a two-site immunometric assay, c) the a circadiane rhythm of TuM2Pk in blood by measuring levels every 4 hours in 5 patients, d) TuM2Pk- expression in serum (see 2.) in 5 patients by taking blood from tumor-side vena renalis compared to peripherally blood, e) TuM2Pk (see point 2.) in 40 RCC-patients comparing the results with 39 healthy persons and clinical data of RCC, f) the influence of wound healing to TuM2Pk by measuring serum-levels during a period of more than 12 weeks in 6 patients, g) the individual follow up of 4 patients with RCC stage Robson III for more than 2 years. Comparing TuM2Pk-levels to findings of staging by computed tomography. RESULTS: The isoenzyme TuM2Pk could be demonstrated in RCC and their metastases by immunohistochemistry with a monoclonal antibody specific for pyruvate kinase type M2. In normal kidney cells pyruvate kinase type M2 is not detectable. The stability of TuM2Pk was studied in the serum within 30 minutes. No circadian rhythm was found. Most serum TuM2Pk comes from tumor. Serum evaluation in 39 healthy persons was used to determine normal values, with an upper concentration of 28 U/ml of TuM2Pk (95% percentile of normal healthy persons). Serum evaluation in 40 RCC showed a significant difference to healthy persons and a positive correlation with Robson stage and grading No correlation of TuM2Pk was found with histopathological cell type of tumor diameter. After radical nephrectomy normalization of TuM2Pk level was found within 11 weeks in all localized RCC. Continuously elevated serum levels were seen in metastatic RCC. Individual follow-up seems to be possible. CONCLUSION: Initial discrimination is not possible between localized and metastasized RCC using TuM2PK; however, it is possible to differentiate between benign and malignant renal processes; the specificity under these circumstances is 75%. After successful surgery of localized RCC, an elevated TuM2Pk will be normalized within 11 weeks, and will be remain elevated or will increase again in case of RCC-relapse or metastasis. Thus TuM2Pk would appear to be a useful marker for RCC detection and follow-up.

Antibodies, Monoclonal↗

Immunohistological investigations of carcinoembryonic antigen (CEA) in urothelial carcinomas.

CEA is discussed as a potential tumour marker for carcinomas of the urothelium. However, investigations by means of polyclonal antibodies have shown various cross reactions which are not to be expected with monoclonal antibodies (MAb). Immunohistochemistry was done with the MAb anti-CEA BW 431/26 (Behring), N 1522 (Dako), and C 7292 (Sigma) on 37 carcinomas of the urothelium (grades 1-3). The MAb BW 431/26 showed the best results concerning specificity and sensitivity. In general, immunohistological investigations demonstrated negative or moderate staining reactions. Positive reactions were seen in 32% (12/37) of the carcinomas. Staining intensity for CEA correlated with differentiation grade. On the whole, a maximum of 5% of the tumour cells were CEA positive. Our results indicate that monoclonal anti-CEA antibodies are not usefull as a tumour marker for urothelial carcinomas. For the suitability of CEA for in vitro and for in vivo diagnosis a threshold of CEA positive tumour cells has to be defined.

Adenocarcinoma↗

Molecular genetic methods in the diagnosis of invasive bladder cancer.

Development and progression of tumours is generally driven by an accumulation of genetic alterations. In this study we correlated chromosome 17 aneuploidy to invasiveness of bladder cancer by the method of fluorescence in situ hybridisation (FISH) in urinary cytospins. We investigated the value of FISH compared to DNA cytophotometry in the diagnosis of bladder cancer. 39 patients with or suspicious for bladder tumour were analyzed. 19 patients had a bladder tumor at the time of diagnosis, 14 superficial (Ta-T1) and 5 invasive (T2-3). The remaining 20 patients had no tumour at the time of diagnosis, however 9 of them had one in prehistory (Ta-T2). For FISH we used the DNA probe of HER-2/neu located on chromosome 17. DNA image cytometry was performed according to single cell interpretation of Böcking. Our results showed a correlation between HER-2/neu CEP 17 alterations and invasive bladder cancer to the extent of 10-70% aberrant cells for patients with current invasive bladder tumour as well as for patients who had been cured but with as invasive bladder cancer in prehistory. On the other hand, the percentage of aneuploid cells for negative biopsy and superficial tumour was 0-2%. The DNA cytophotometry brought an uniform aneuploidy only for present invasive tumours: negative biopsies, superficial cancer and invasive tumour just in prehistory, showed mixed diploid-aneuploid DNA patterns. Our results showed that for the detection of aberrant tumour cells the method of FISH is more sensitive than DNA cytometry. FISH could provide important information in the prognosis of bladder cancer.

Adult↗

Immunohistochemical examinations (Ki67, p53, nm23) and DNA cytophotometry in bladder cancer.

Bladder cancer is clinically characterized by a high recurrence rate for superficial tumours up to 70% and by the invasiveness of advanced bladder cancer. To learn more about the biological behaviour of an individual bladder cancer different tumour markers have been investigated. The aim of our study was to compare the potential of aggression of both superficial and invasive bladder tumours by means of the proliferation marker Ki67, the tumour suppressor gene p53, the non metastasizing protein nm23 and the evaluation of DNA ploidy. We examined 36 patients, 28 with a bladder tumour (Ta-T4) and 8 without as a control group. For immunohistochemistry (Ki67, p53, nm23) we took paraffin sections and scored semiquantitatively under a microscope. The DNA cytophotometry was done on bladder washings by evaluating the DNA ploidy of single cells. The results showed that benign tissues were negative for Ki67 and p53 but positive for nm23. The DNA diagnosis was diploid for all benign samples. The superficial bladder cancer (Ta, T1) showed, in comparison to the invasive tumours, significantly lower numbers of aneuploid cells and a higher rate of p53 mutations. On the other hand the invasive tumours (T2-4) were correlated to significantly higher proliferation rates and higher potencies for metastasizing. The combination of the investigated tumour markers allowed a graduation of the biological behavior of an individual bladder cancer. Especially a high p53 mutation rate and a non aneuploid DNA diagnosis were indicators for the recurrence of superficial bladder tumours. Invasive growth of bladder cancer was characterized by high Ki67 proliferation and low nm23 protein binding.

Adult↗

Serologic angiogenesis factors and microvascular density in renal cell carcinoma: two independent parameters.

Renal Cell Carcinoma (RCC) is characterized by high intratumoral microvascular density (iMVD) and significantly elevated serologic titers of angiogenesis factors, basic fibroblast growth factor (bFGF), vascular endothelial growth factor (vEGF) and angiogenin (Ag). The goal of the present study was to find whether a correlation exists between any of these factors and intratumoral microvascular density (iMVD). Serologic angiogenesis factors were determined directly before nephrectomy of a tumorous kidney in 12 patients (average age: 67.6 years [49-78] with localized clear-cell RCC (Robson I-II) (Quantikine', R&D Systems Europe, Abington, UK). Sections were taken in each case from the microscopically most aggressive area of the tumorous kidney preparations. Staining was carried out with a primary antibody against CD31 (DAKO M 0823, Hamburg, Germany). iMVD was counted at 160x magnification at five "hot spots" 200 x 200 microns in size, and the individual factors were then correlated with the areas of maximum and average iMVD (iMVDmax, iMVD-d). Average concentrations of 38 pg/ml +/- 68 were found for bFGF, 712 pg/ml +/- 791 for vEGF, and 358 ng/ml +/- 97 for Ag. iMVDmax was 20 +/- 11 per area, iMVD-d was 410/mm2 +/- 243. No correlation was found between microvascular density and serologic angiogenesis factors for any parameter. Actual tumor vascularization, expressed as iMVD, was not correlated with the 3 angiogenesis parameters which were studied. On the one hand, this raises the question whether angiogenesis can be measured at all with these parameters; on the other, it remains nuclear whether the continuous process of angiogenesis can be registered at all by chronologic, specific factor analysis.

Aged↗