Biomedical subjects

C Decaestecker

Publications and source records attributed to C Decaestecker.

At least 55 records · Page 3Linked to original sources

PubMed1999

Galectin-1 and galectin-3 binding pattern expression in renal cell carcinomas.

We studied 2 families of molecules whose role remains uncharacterized or obscure in the progress of renal cell carcinoma (RCC): galectins, a major class of glycoproteins, and the Thomsen-Friedenreich (T) antigen. We characterized the level of expression of galectin-1 and galectin-3 and their respective binding sites in a series of 74 RCCs. We also characterized the level of expression of laminin, a natural ligand for galectins. Finally, we characterized the level of T antigen expression and the T antigen binding sites. All levels of expression were quantitatively determined by using computer-assisted microscopy on immunohistochemically or glycohistochemically stained slides. A small concentration of galectin-1 binding sites or a large concentration heterogeneity of galectin-3 can be associated with unfavorable prognoses for patients with grade II or III RCCs. In contrast, T antigen and T antigen binding sites revealed no change across the 2 RCC groups that exhibited different clinical outcomes. We established discriminant scores that permitted a clear distinction between the 2 RCC groups analyzed. Modifications to the expression of galectin-1 and galectin-3, but not of T antigen, parallel an increase in RCC aggressiveness. Galectins represent a family of molecules with a meaningful role in RCC progression.

Antibodies, Monoclonal↗

PubMed1999

Determination of the levels of expression of sarcolectin and calcyclin and of the percentages of apoptotic but not proliferating cells to enable distinction between recurrent and nonrecurrent cholesteatomas.

OBJECTIVES: To investigate in a series of cholesteatomas 1. whether subgroups of cholesteatomas with specific proliferative/apoptotic features exhibit distinct differentiation markers and 2. whether these different subgroups identified at the biological level relate to specific groups of clinically identified cholesteatomas. STUDY DESIGN: Analysis of 55 cholesteatomas resected by the same surgeon, by means of canal wall up and canal wall down surgical procedures. METHODS: Two differentiation markers were used: biotinylated sarcolectin (to identify sarcolectin-binding sites) and a monoclonal antibody directed against calcyclin (which is the S100A6 protein). The growth pattern in cholesteatomas was characterized at three distinct levels: 1. the cell proliferation level determined by means of the MIB-1 antibody, which enables the Ki-67 cell-cycle-related antigen to be identified on archival material; 2. the apoptosis level determined by means of the in situ labeling of nuclear DNA fragmentation (TUNEL staining); and 3. the p53 tumor suppressor gene-related product determined by means of p53 immunohistochemistry. RESULTS: The cholesteatomas that exhibited the highest proportion of apoptotic cells were those which exhibited the highest level of sarcolectin-binding sites (i.e., sialic acids). In contrast, the cholesteatomas exhibiting the lowest level of both proliferation and apoptosis showed the highest level of calcyclin. Recurrent cholesteatomas can be identified from nonrecurrent ones on the basis of three features, namely, the level of apoptotic cells, the way in which the apoptotic cells are distributed (i.e., homogeneously vs. heterogeneously), and the percentage of calcyclin-positive cells. CONCLUSIONS: The present data emphasize the existence of distinct subgroups of cholesteatomas identifiable at both cell kinetic and differentiation levels. Some of the biological variables used here to identify distinct biological subgroups of cholesteatomas in turn enabled some biological variables to be identified, so making it possible to classify the cholesteatomas in terms of recurrence versus nonrecurrence.

Adolescent↗

PubMed1999

Supratentorial pilocytic astrocytomas, astrocytomas, anaplastic astrocytomas and glioblastomas are characterized by a differential expression of S100 proteins.

The levels of expression of the S100A1, S100A2, S100A3, S100A4, S100A5, S100A6 and S100B proteins were immunohistochemically assayed and quantitatively determined in a series of 95 astrocytic tumors including 26 World Health Organization (WHO) grade I (pilocytic astrocytomas), 23 WHO grade II (astrocytomas), 25 WHO grade III (anaplastic astrocytomas) and 21 WHO grade IV (glioblastomas) cases. The level of the immunohistochemical expression of the S100 proteins was quantitatively determined in the solid tumor tissue (tumor mass). In addition twenty blood vessel walls and their corresponding perivascular tumor astrocytes were also immunohistochemically assayed for 10 cases chosen at random from each of the four histopathological groups. The data showed modifications in the level of S100A3 protein expression; these modifications clearly identified the pilocytic astrocytomas from WHO grade II-IV astrocytic tumors as a distinct biological group. Modifications in the level of S100A6 protein expression enabled a clear distinction to be made between low (WHO grade I and II) and high (WHO grade III and IV) grade astrocytic tumors. Very significant modifications occurred in the level of S100A1 protein expression (and, to a lesser extent, in their of the S100A4 and S100B proteins) in relation to the increasing levels of malignancy. While the S100A5 protein was significantly expressed in all the astrocytic tumors (but without any significant modifications in the levels of malignancy), the S100A2 protein was never expressed in these tumors. These data thus indicate that several S100 proteins play major biological roles in human astrocytic tumors.

Adolescent↗

PubMed1999

A pilot study for identifying at risk thyroid lesions by means of a decision tree run on clinicocytological variables.

Fine-needle aspiration biopsy (FNAB) is safe, inexpensive, minimally invasive, and highly accurate in the diagnosis of nodular diseases of the thyroid. However, FNAB does not provide a reliable benign versus malignant diagnosis for 100% of the cases analysed. It is possible to increase the accuracy of the cytological diagnosis by means of information contributed by different clinical variables. In the present study we evaluate the diagnostic value of 10 variables in addition to FNAB on a series of 218 specimens for which we obtained histological diagnoses including 37 cancers (17%). The diagnostic information contributed by these variables was analyzed by means of the Decision Tree technique, an artificial intelligence-related method which forms part of the Supervised Learning algorithms. The results show that Decision Trees enable some subpopulations of patients with uncertain FNAB results to be characterized.

Adolescent↗

PubMed1999

D-mannose and N-acetylglucosamine moieties and their respective binding sites in salivary glands of Sjögren's syndrome.

OBJECTIVE: Sjögren's syndrome (SS) is an autoimmune exocrinopathy. The mannose binding lectin (MBL), a pluripotent molecule of the innate immune system, is involved in the pathogenesis of autoimmune diseases. We investigated whether specific ligands for MBL and MBL related structures could be reliable markers in cases of SS. METHODS: The labial salivary glands of 19 patients fulfilling the diagnostic criteria for primary (n=11) and secondary SS (n=8) were studied. Seven healthy women served as controls. Computer assisted microscopy was employed to determine quantitatively the percentage of positive structures (acini, ducts, and interlobular connective tissue), the staining intensity, and the level of staining heterogeneity for 4 glycohistochemical probes including wheat germ agglutinin and concanavalin (Con A) as lectins, and mannose and N-acetylglucosamine as parts of neoglycoproteins. The data were evaluated by discriminant analysis. RESULTS: The data strongly suggest that MBL related structures, if not MBL itself, could play distinct roles in the pathogenesis of primary versus secondary SS. Further, quantitative determination of the level of expression of D-mannose and N-acetylglucosamine and their respective binding sites in labial salivary gland acini offers a powerful diagnostic tool for distinguishing primary from secondary SS. CONCLUSION: In SS labial salivary glands, determination of the level of acceptor sites for wheat germ agglutinin, Con A, D-mannose, and N-acetylglucosamine provides information on the roles played by glycoforms in SS. The methodology and data described in this paper should provide pathologists with objective diagnostic markers for SS. Our results should enhance the biological understanding of this pathology.

Acetylglucosamine↗

PubMed1998

Gastrin inhibits motility, decreases cell death levels and increases proliferation in human glioblastoma cell lines.

Whether they are of low or high histopathological grade, human astrocytic tumors are characterized by a marked propensity to diffuse into large areas of normal brain parenchyma. This invasion relates mainly to cell motility, which enables individual cell migration to take place. The present study characterizes in vitro the gastrin-mediated effects on both the growth (cell proliferation vs. cell death) and motility dynamics of the human U87 and U373 glioblastoma cell lines. A computer-assisted phase-contrast microscope was used to track the number of mitoses versus cell deaths every 4 min over a 72-h period and so to quantitatively describe the trajectories of living U373 and U87 cells growing on plastic supports in culture media both with and without the addition of 0.1, 5, or 100 nM gastrin. While 5 or 100 nM gastrin only weakly (p < .05 to p < .01) increased cell proliferation in the U87 cell line and not in U373 one, it very significantly (p < .001) inhibited the amount of cell death at 5 and 100 nM in both the U87 and U373 lines. In addition, 5 nM gastrin markedly inhibited cell mobility in U87 (p < .00001) and U373 (p < .0001) glioblastoma models. All these data strongly suggest that gastrin plays a major role in the biological behavior of the in vitro U87 and U373 human glioblastoma cell lines in matters concerning their levels of cell motility and growth dynamics.

Amino Acid Sequence↗

PubMed1998

Discrimination between chronic pancreatitis and pancreatic adenocarcinoma using artificial intelligence-related algorithms based on image cytometry-generated variables.

The incidence of pancreatic adenocarcinomas (PA) is increased in the setting of chronic pancreatitis. Distinguishing chronic pancreatitis from pancreatic adenocarcinomas is often difficult, and is based on routine brush cytological specimens provided during endoscopic retrograde cholangiopancreatography (ERCP). Reactive epithelial changes in chronic pancreatitis may appear similar to those of a well-differentiated cancer. Brush cytology specimens were obtained during ERCP from 49 patients with diseases for which the differential diagnosis included chronic pancreatitis and/or pancreatic adenocarcinoma Image cytometry was performed involving the assessment of between 200-400 Feulgen-stained nuclei per case; for each case, 40 quantitative cytometric variables were generated. Data analysis was performed using artificial intelligence methods of data classification that produced decision trees and production rule systems. Different classification models were produced for a subset of 34 patients. The best models were identified by the use of a sampling technique (leave-one-out), and were tested on the remaining 15 patients. These models were based on 5 of the 40 variables associated with a significant discriminatory function. Pancreatic adenocarcinoma was diagnosed in the training data set of 34 patients during a leave-one-out process with an estimated sensitivity of 91% and specificity of 87%. Both sensitivity and specificity were 80% in the independent test set of 15 patients. We conclude that inflammatory and malignant pancreatic epithelia exhibit distinct morphological features that can be distinguished by decision tree-based classifiers employing image-cytometric numerical data.

Adenocarcinoma↗

PubMed1998

Image cytometry as a discriminatory tool for cytologic specimens obtained by endoscopic retrograde cholangiopancreatography.

BACKGROUND: Routine brush cytology is relatively insensitive for the diagnosis of biliary and pancreatic malignancy. Sensitivity can be improved by measuring DNA and proliferation. The goal of this study was to assess the discriminatory capacity of image cytometry using pancreaticobiliary brush cytology specimens obtained during endoscopic retrograde cholangiopancreatography (ERCP). Analysis included morphometry, DNA quantification, and characterization of nuclear chromatin distribution and condensation. METHODS: Brush cytology specimens were obtained during ERCP from 22 chronic pancreatitis specimens, 11 pancreatic adenocarcinoma specimens, 13 primary sclerosing cholangitis specimens, and 11 cholangiocarcinoma specimens and contrasted with 25 normal epithelia specimens. A SAMBA 2005 image processor was used to analyze Feulgen stained chromatin density and distribution. Discriminant analysis of 37 morphonuclear variables was performed to characterize differences between: 1) chronic pancreatitis and pancreatic adenocarcinoma, and 2) primary sclerosing cholangitis and cholangiocarcinoma. RESULTS: Chronic pancreatitis was distinguished from pancreatic adenocarcinoma (P < or = 0.001); sensitivity and specificity were both estimated to be 82%. Primary sclerosing cholangitis was distinguished from cholangiocarcinoma (P < or = 0.01); sensitivity and specificity were estimated to be 82% and 85%, respectively. CONCLUSIONS: Multiparameter image cytometry has potential as an adjuvant diagnostic technique in patients with pancreaticobiliary malignancy.

Adenocarcinoma↗

PubMed1998

Quantitative glycohistochemistry defines new prognostic markers for cancers of the oral cavity.

BACKGROUND: Histopathologic grading and clinical staging cannot provide a precise prognosis of oral cavity cancer patients. The use of glycohistochemical markers may improve the level of prognostic accuracy of such conventional classification systems. METHODS: Computer-assisted microscopy was employed in a series of 40 oral cavity cancers to determine quantitatively the percentage of positive cells, the staining intensity, and the level of staining heterogeneity for 3 glycohistochemical markers, including peanut agglutinin (PNA), Thomsen-Friedenreich antigen (T antigen) as part of a neoglycoprotein, and sarcolectin. Data were evaluated by discriminant analysis. RESULTS: Although the level of differentiation (P < 0.01 to P < 0.001) and the T variable of the TNM staging system (P < 0.05 to P < 0.01) related mainly to the level of expression of the acceptor sites for PNA and the T antigen, the patient survival period (P < 0.05) was largely a fraction of the level of expression of the acceptor sites for the carrier-immobilized T antigen and for sarcolectin. CONCLUSIONS: In oral cavity cancer, determining the level of acceptor sites for PNA, T antigen, and sarcolectin provides useful information on histopathologic differentiation, clinical staging, and survival. Because these processes of determination were carried out quantitatively, a discriminant model was set up, which enabled the level of oral cavity cancer aggressiveness to be characterized precisely. The current methodology described in this article should therefore afford pathologists original and quantitative (and thus objective) prognostic markers for oral cavity cancers.

Adult↗

PubMed1998

The in vitro influence of eight hormones and growth factors on the proliferation of eight sarcoma cell lines.

Little is known about the regulation of sarcoma proliferation by hormones and/or growth factors. We therefore characterised the in vitro proliferative influence on eight sarcoma cell lines of the platelet-derived growth factor, the insulin-like growth factor 1, triiodothyronine, the epidermal growth factor, the luteinising-hormone-releasing hormone, progesterone, gastrin and 17 beta-oestradiol. The influence of the different factors on the proliferation of sarcoma cell lines was measured by the colorimetric 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide test. Two culture media were studied: (1) a nutritionally poor medium containing 2% of fetal calf serum and (2) a nutritionally rich one containing 5% or 10% FCS both with and without the addition of non-essential amino acids. The results were analysed either by conventional statistical analyses or by a classification method based on a decision-tree approach developed in Machine Learning. This latter method was also compared to other classifiers (such as logistic regression and k nearest neighbours) with respect to its accuracy of classification. Monovariate statistical analysis showed that each of the eight cell lines exhibited sensitivity to at least one factor, and each factor significantly modified the proliferation of five or six of the eight cell lines under study. Of these eight lines one of fibrosarcoma origin was the most "factor-sensitive". Decision-tree-related data analysis enabled the specific pattern of factor sensitivity to be characterised for the three histological types of cell line under study. The effects of hormone and growth factors are significantly influenced by the type of culture medium used. The method used appeared to be an accurate classifier for the kind of data analysed. Sarcoma proliferation can be modulated, at least in vitro, by various hormones and growth factors, and the proliferation of each histopathological type exhibited a distinct sensitivity to different hormone and/or growth-factors.

Cell Division↗

PubMed1998

Determination of growth fraction and cell density to evaluate the potential growth of human oligodendroglial and astrocytic tumours.

UNLABELLED: The object of this work was PURPOSE: to develop a methodology that enables net tumour growth, a balance between actual tumour growth and tumour cell loss, to be approximately evaluated. METHODS: The methodology proposed relies on detecting the growth fraction immunohistochemically by means of MIB-1 antibody labelling combined with cell density determination, carried out on 5-microm-thick Feulgen-stained histological sections with computer-assisted microscopy. The series investigated included 25 oligodendrogliomas (OLG-II), 9 anaplastic oligodendrogliomas (OLG-III). 13 astrocytomas (AST), 14 anaplastic astrocytomas (ANA) and 8 mixed oligoastrocytomas (OLG-AST). RESULTS: The results show that the biological characteristics of some cases were in total accordance with their histopathological diagnoses. This was the case for the "weakly proliferating weakly dense" OLG-II and AST-II tumours, and for the "highly proliferating highly dense" OLG-III and AST-III ones. In contrast, the biological characteristics of some cases seemed to contradict the histopathological case labels. This was the case for the "highly proliferating highly dense" OLG-II and AST-II tumours, the biological aggressiveness of which would be undervalued on the basis of the morphology-based grading system alone, and also for the "weakly proliferating weakly dense" OLG-III and AST-III tumours, the aggressiveness of which would be overvalued. CONCLUSIONS: Combining the determinations of the MIB-1 and the cell density variables appears to be satisfactory in terms of the cell kinetic characterization of glial tumours as a complement to the prognostic information given by a morphology-based grading system alone.

Adult↗

PubMed1998

Growth inhibition of human in vitro and mouse in vitro and in vivo mammary tumor models by retinoids in comparison with tamoxifen and the RU-486 anti-progestagen.

Retinoids constitute a very promising class of agents for the chemoprevention or treatment of breast cancer. These retinoids exert their biological activity through two distinct classes of retinoic acid (RA) receptors (R), the RAR isotypes (alpha, beta, and gamma) and the three RXR isotypes (alpha, beta, and gamma) and their numerous isoforms which bind as RXR/RAR heterodimers to the polymorphic cis-acting response elements of RA target genes. With respect to these numerous receptor sub-types, the retinoid-induced effects at the biological level include marked modifications with respect to both cell proliferation and cell death (apoptosis), and also in the induction of differentiation processes. The present study aims to characterize the effect which four retinoids (TTNPB, 9-cis-RA, LGD 1069, 4-HPR) with distinct RAR/RXR binding properties induced on various in vitro and in vivo mouse and human breast cancer models. The experiments with the retinoids were carried out in comparison with the anti-estrogen tamoxifen and the anti-progestagen RU-486 compounds. The results show that the 6 compounds under study were markedly more efficient in terms of growth inhibition in the human T-47D cell line when maintained under anchorage-independent culture conditions than when maintained under anchorage-dependent ones. While RU-486 exhibited a weak statistically significant (p < 0.05) influence on the growth of the T-47D stem cells, tamoxifen had a marked inhibitory influence on the growth of these cells. Of the four retinoids, 4-HPR was the least effective since the lowest doses tested (1 and 0.1 nM) exhibited no statistically (p > 0.05) significant influence on the growth of the stem cells. The most efficient retinoid was TTNPB. It was only at the highest dose (10 microM) that tamoxifen and RU-486 showed a weak inhibitory influence on the growth of the T-47D non-stem cells while all 4 retinoids exerted a significant inhibitory influence on the growth of these non-stem cells, with 4-HPR being the most efficient (P < 0.001) at the highest dose, but ineffective (P > 0.05) at the lowest. Tamoxifen and TTNPB were tested in vivo on hormone-sensitive (HS) and hormone-insensitive (HI) strains of the MXT murine mammary carcinoma. While TTNPB appeared to be equally efficient in terms of growth inhibition in both MXT-HS and MXT-HI models, tamoxifen had only a marginal inhibitory influence on the growth of the MXT-HI strain but did inhibit growth in the case of the MXT-HS one. TTNPB was markedly more efficient than tamoxifen in terms of both inhibiting the cell proliferation level (measured by means of computer-assisted microscopy applied to Feulgen-stained nuclei, a method which enables the percentage of cells in the S phase of the cell cycle to be determined) and triggering cell death (measured by means of the determination of the transglutaminase activity) in both the MXT-HI and MXT-HS models. The very significant TTNPB-induced inhibition of the macroscopic MXT-HS growth rate relates to the triggering of cell death (apoptosis) rather than to an inhibition of cell proliferation. All these results clearly indicate that retinoids are very efficient agents against breast cancer, at least as efficient as tamoxifen.

Alitretinoin↗

PubMed1998

Characterization of astroglial versus oligodendroglial phenotypes in glioblastomas by means of quantitative morphonuclear variables generated by computer-assisted microscopy.

The current WHO classification places glioblastomas in the astrocytoma category. However, whether or not glioblastomas also show oligodendroglial differentiation remains a matter of controversy. This study investigates, at the morphonuclear level, the hypothesis that some glioblastomas (GBMs) may also represent the ultimate level of malignancy in the oligodendroglial lineage. Using a series of 164 GBMs, we sought to ascertain whether any of these GBMs exhibited phenotypical characteristics that were more closely related to oligodendroglial lineages than astrocytic lineages. Phenotypical features were quantitatively determined by means of the computer-assisted microscope analysis of Feulgen-stained nuclei, a process that made it possible to quantitatively describe the patterns of the cell nuclei (and, more specifically, of their chromatin) through 16 variables, and the distribution of the nuclear DNA content (DNA ploidy) through 8 variables. The phenotypical characteristics typical of astrocytic and oligodendroglial tumors were analyzed by means of Discriminant Analysis, a statistical multivariate analysis, performed on a series of 65 astrocytic and oligodendroglial tumors. This series consisted of 14 WHO grade II and 19 grade III astrocytomas and 24 WHO grade II and 8 grade III oligodendrogliomas. This multivariate analysis enabled an accurate model to be produced that distinguished between astrocytomas and oligodendrogliomas on the basis of 5 cytometry-generated variables. This model was used to characterize the phenotype of each of the 164 glioblastomas. The results show that of these 164 glioblastomas, 6 (about 3.5%) displayed phenotypes that were very similar to oligodendrogliomas, and 141 displayed phenotypes that were very similar to astrocytomas. The phenotypes of the 17 remaining GBMs were too ambiguous to be categorized as having a pure astrocytic or oligodendroglial lineage.

Adolescent↗

PubMed1998

Corporeal veno-occlusive dysfunction: a distal arterial pathology?

PURPOSE: Alteration of intracavernous smooth muscle cells has been demonstrated in patients with pure venous leakage. This modification seems correlated with reduction of intracavernous oxygen tension. However, Doppler imaging of the cavernous arteries in these patients is normal. To understand the ischemic factor we studied the endothelium of the terminal arteries with computerized image analysis and immunohistochemical staining with 2 types of lectin in patients with venous leakage and those with normal erections. Lectins are glycoproteins that can be used as histological markers to monitor functional and pathological changes. MATERIALS AND METHODS: Four patients 44 to 59 years old with normal erections who were operated on for penile cancer and 11 patients 27 to 62 years old with pure venous leakage (flow to maintain erection greater than 15 ml. per minute and cavernous flow velocity greater than 35 cm. per second) were included in the study. Immunohistochemical staining with 2 lectins, wheat germ agglutinin and Ulex europeaus agglutinin I, was performed and analyzed with computerized image analysis. The labeling index which relates to the percentage of staining indicates the distribution of the endothelial cells, and mean optical density which relates to the staining intensity indicates the function of these cells. RESULTS: Mean labeling index values for the 2 lectins were similar in both groups (p >0.05). Mean optical density values for the 2 lectins were significantly greater for the patients with normal erections (p <0.01). Therefore, the distribution of the endothelial cells was the same while their function was different in patients with corporeal veno-occlusive dysfunction. CONCLUSIONS: Staining with wheat germ agglutinin and Ulex europeaus agglutinin I lectin types allowed us to detect alteration in the glyco-histochemistry of the endothelial cells of the small arteries, and venous leakage could be the first step in vasculogenic impotence.

Adult↗

PubMed1998

Improving morphology-based malignancy grading schemes in astrocytic tumors by means of computer-assisted techniques.

We propose an original methodology which improves the accuracy of the prognostic values associated with conventional morphologically-based classifications in supratentorial astrocytic tumors in the adult. This methodology may well help neuropathologists, who must determine the aggressiveness of astrocytic tumors on the basis of morphological criteria. The proposed methodology comprises two distinct steps, i.e. i) the production of descriptive quantitative variables (related to DNA ploidy level and morphonuclear aspects) by means of computer-assisted microscopy and ii) data analysis based on an artificial intelligence-related method, i.e. the decision tree approach. Three prognostic problems were considered on a series of 250 astrocytic tumors including 39 astrocytomas (AST), 47 anaplastic astrocytomas (ANA) and 164 glioblastomas (GBM) identified in accordance with the WHO classification. These three problems concern i) variations in the aggressiveness level of the high-grade tumors (ANA and GBM), ii) the detection of the aggressive as opposed to the less aggressive low-grade astrocytomas (AST), and iii) the detection of the aggressive as opposed to the less aggressive anaplastic astrocytomas (ANA). Our results show that the proposed computer-aided methodology improves conventional prognosis based on conventional morphologically-based classifications. In particular, this methodology enables some reference points to be established on the biological continuum according to the sequence AST-->ANA-->GBM.

Adult↗

PubMed1998

The chromatin pattern of cell nuclei is of prognostic value for renal cell carcinomas.

Using a series of 105 renal cell carcinomas (RCCs) we investigated whether features quantitatively describing the appearance of Feulgen-stained nuclei and, more particularly, of their chromatin (on the basis of computer-assisted microscopy) can contribute any significant prognostic information. Thirty morphonuclear and 8 nuclear DNA content-related variables were thus generated. The actual prognostic values of this set of cytometric variables was compared (by means of discriminant statistical analysis) to conventional diagnostic and/or prognostic markers including histopathological grades, tumour invasion levels and the presence or absence of metastases. We obtained complete clinical follow-ups for 49 of the 105 RCC patients under study, making it possible to define a subset of patients with a bad prognosis (i.e., who died in the 12 months following nephrectomy) and a subset of patients with a good prognosis (i.e., who survived at least 24 months following nephrectomy). An original method of data analysis related to artificial intelligence (decision tree induction) enabled a strong prognostic model to be set up. In the case of 10 new patients, this model identified all the dead patients as having a bad survival status, with a total of 8 correct predictions. Another prognostic model similarly generated enabled the correct predictions to be confirmed.

Adult↗

PubMed1998

Applications of lectins and neoglycoconjugates in histology and pathology.

The biological importance of oligosaccharide sequences in many different settings is undeniable. Glycan histochemistry has brought together the histological and biochemical approaches and provided insight into the mutual importance of both approaches. The aim of the authors is to take a look at a number of ways in which modern glycohistochemistry contributes to acquiring knowledge about the key role played by carbohydrates in the physiology of vertebrate tissues and human disease. The versatility of lectin and neoglycoconjugate histochemical procedures is emphasized.

Animals↗

PubMed1998

Setting up of an original computer-assisted methodology to characterize in vitro drug-induced anti-angiogenic effects.

The development of angiogenesis within a tumor brings on a sequence of extremely complex molecular events. We have developed a methodology which enables a wide set of biological parameters to be quantitatively determined in the field of anti-angiogenesis pharmacology. This methodology which includes a video cell tracking device, is unique because it offers the possibility of evaluating the specific influence of a given compound with potential anti-angiogenic properties on cell cycle kinetics, cell death, global cell line growth, and cell motility. We chose TNP-470, a synthetic analogue of fumagilin, to test our methodology on HUVEC cell lines taken from various human umbilical cord veins. The experiments carried out with TNP-470 did not confirm all the data reported in the literature. Our results show that i) TNP-470 could be considered as a cytotoxic agent; ii) this compound had an apparently marginal cytostatic effect; and iii) it did not increase the apoptosis level. Our methodology also revealed that the HUVEC cell lines are very heterogeneous in terms of different biological parameters. This highlights the problem of the reproductibility of the result.

Angiogenesis Inhibitors↗