Biomedical subjects

C Decaestecker

Publications and source records attributed to C Decaestecker.

At least 55 records · Page 3Linked to original sources

PubMed1999

Computer-assisted analysis of epiluminescence microscopy images of pigmented skin lesions.

BACKGROUND: Epiluminescence microscopy (ELM) is a noninvasive clinical tool recently developed for the diagnosis of pigmented skin lesions (PSLs), with the aim of improving melanoma screening strategies. However, the complexity of the ELM grading protocol means that considerable expertise is required for differential diagnosis. In this paper we propose a computer-based tool able to screen ELM images of PSLs in order to aid clinicians in the detection of lesion patterns useful for differential diagnosis. METHODS: The method proposed is based on the supervised classification of pixels of digitized ELM images, and leads to the construction of classes of pixels used for image segmentation. This process has two major phases, i.e., a learning phase, where several hundred pixels are used in order to train and validate a classification model, and an application step, which consists of a massive classification of billions of pixels (i.e., the full image) by means of the rules obtained in the first phase. RESULTS: Our results show that the proposed method is suitable for lesion-from-background extraction, for complete image segmentation into several typical diagnostic patterns, and for artifact rejection. Hence, our prototype has the potential to assist in distinguishing lesion patterns which are associated with diagnostic information such as diffuse pigmentation, dark globules (black dots and brown globules), and the gray-blue veil. CONCLUSIONS: The system proposed in this paper can be considered as a tool to assist in PSL diagnosis.

Computer Simulation↗

PubMed1999

Improving the prognostic value of histopathological grading and clinical staging in renal cell carcinomas by means of computer-assisted microscopy.

The present work aims to refine prognosis in cases of renal cell carcinoma (RCC) by integrating a variety of parameters with the prognostic information provided by histopathological grading and clinical staging, carried out on a series of 97 RCCs. To this end, Feulgen-stained RCC cell nuclei were characterized by means of 38 variables describing nuclear DNA ploidy levels and morphology. All of these data were subjected to a principal components analysis. On the basis of this multivariate analysis, Fuhrman grade II was subdivided into grades II- and II+, and Fuhrman grade III into grade III- and III+. The same kind of subcategorization was performed in the case of the T2 and T3 clinical stages. The results show that the classification into grade II- and III- RCCs correspond to a more favourable prognosis than grade II+ and III+, to which shorter survival periods were attributable. Similar results were obtained for the subcategorization of the T2 and T3 clinical stages. Very simple biological characterizations of these grade- or stage-related RCC groups were obtained by means of a decision tree approach applied to the cytometry-generated variables. The resulting classification rules were validated on a new series of 18 patients and enabled very accurate predictions of survival.

Adult↗

PubMed1999

In vitro influence of lectins and neoglycoconjugates on the growth of three human sarcoma cell lines.

PURPOSE: The aim of our study is to investigate the in vitro effects of plant lectins, galectins and neoglycoconjugates on the proliferation of three human sarcoma cell lines. METHODS: Proliferation was assessed by means of the tetrazolium derivative reduction (MTT) assay. In addition, glycohistochemistry was used to make visible the plant-lectin-specific binding sites; the intensity of the lectin binding pattern was quantified by means of image analysis. RESULTS: Depending on the cell lines, the staining intensity and the percentage of labelled cells were different. With respect to growth modulation, the cell lines also responded differently to the probes used. Besides a predominant inhibitory effect elicited by the probes at 50 microg/ml, dose-dependent effects, including growth stimulation, were detectable in several instances. These effects relate to the animal galectins tested and several neoglycoconjugates, e.g. the lactose- and blood-group-A-trisaccharide-bearing probes. CONCLUSIONS: Endogenous lectins and lectin-reactive cellular glycoconjugates can apparently affect the regulation of the growth of human sarcoma cells. We suggest that these results are relevant for further histopathological monitoring in correlation with prognosis and in vitro assays to reveal possible clinical applications.

Cell Division↗

PubMed1999

The influence of L-triiodothyronine, L-thyroxine, estradiol-17beta, the luteinizing-hormone-releasing hormone, the epidermal growth factor and gastrin on cell proliferation in organ cultures of 35 benign and 13 malignant human thyroid tumors.

PURPOSE: To characterize the influence of six factors on human thyroid tissues at the cell-proliferation level. These six factors were the epidermal growth factor (EGF), the luteinizing-hormone-releasing hormone (LHRH), triiodothyronine, thyroxine, estradiol and gastrin. METHODS: Forty-eight human thyroid specimens were obtained from surgical resection and maintained alive for 48 h ex vivo (in vitro) under organotypic culture conditions. These specimens comprised 35 benign cases (17 multinodular goiters and 18 adenomas) and 13 cancers. Cell proliferation in the control and treated conditions (at a 5 nM dose) was assessed by means of the thymidine labeling index, which enables the percentage of cells in the S phase of the cell cycle to be determined in accordance with autoradiographic procedures. RESULTS: The results show that, of the six factors tested here, EGF significantly (P < 0.05 to P < 0.001) increased cell proliferation in the greatest number of cancers as compared to what happened with the remaining five. Each of these six factors significantly increased or decreased proliferative cell activity in some 10%-30% of the cases under study. CONCLUSIONS: Triiodothyronine, thyroxine, LHRH and gastrin may increase or decrease cell proliferation in human thyroid tissues, whether benign or malignant, to the same extent as other hormones and/or growth factors such as thyrotropin, EGF, insulin-like growth factor 1, transforming growth factor beta1 and estradiol the effects of which on thyroid cell proliferation are already well documented in the literature.

Adolescent↗

PubMed1999

Grading dysplasia in colorectal adenomas by means of the quantitative binding pattern determination of Arachis hypogaea, Dolichos biflorus, Amaranthus caudatus, Maackia amurensis, and Sambucus nigra agglutinins.

The current study deals with the setting up of a new tool that enables the benign versus the malignant nature of colorectal adenomas to be determined accurately. The 2 objectives are to determine (1) whether adenomas should, or should not, be included in a 2- or a 3-tier grading system, and (2) whether severe dysplasias and carcinomas in situ share common or different biological characteristics. The levels of expression of different types of glycoconjugates were characterized in a series of 166 colorectal specimens, including 14 normal, 90 dysplastic, and 62 cancerous cases. The glycoconjugate expressions were demonstrated for 5 lectins, namely, Arachis hypogaea (PNA), Dolichos biflorus (DBA), Amaranthus caudatus (ACA), Maackia amurensis (MAA) and Sambucus nigra (SNA). The glycoconjugates demonstrated by these 5 lectins belong to the family of the Thomsen-Friedenreich antigens. The binding patterns of the 5 lectins were quantitatively determined by means of computer-assisted microscopy. The quantitative data were submitted to discriminant analyses. Our results show that the specific glycochemical staining patterns could be identified unambiguously and without misclassification between benign (normal and low dysplasia) and malignant (ie, either as moderate/severe dysplasia, carcinoma in situ, or cancer) cases. The data also strongly suggested that (1) dysplasias seem to be distinguishable in 2 instead of 3 groups, that is, low versus moderate/severe (high); and (2) moderate/severe dysplasias are biologically distinct from carcinomas in situ. The methodology developed can be applied directly in routine diagnosis to identify moderate/severe dysplasia specimens already exhibiting features common to carcinomas, and which therefore should be treated consistently in view of the fact that our data strongly suggest that most moderate/severe dysplasias are still benign, whereas carcinomas in situ are real carcinomatous lesions.

Adenoma↗

PubMed1999

Galectin-3 and galectin-3-binding site expression in human adult astrocytic tumours and related angiogenesis.

Using computer-assisted microscopy, the present work aimed to quantitatively characterize the level of the histochemically detectable expression of galectin-3 and galectin-3-binding sites in sections of a series of 84 astrocytic tumours (including 22 grade II, 21 grade III and 41 grade IV specimens) and seven non-tumoural specimens used as controls. The presence of galectin-3 and reactive sites for this lectin were monitored by means of a specific polyclonal anti-galectin-3 antibody (aGal3) and biotinylated galectin-3 (Gal3), respectively. The pattern of expression of galectin-3-binding sites is compared to the pattern of expression of laminin (a potential galectin-3 ligand) revealed using a biotinylated anti-laminin antibody (aLam). Three variables quantitatively characterizing histochemical staining reactions were evaluated by means of computer-assisted microscopy for each of the 3 probes under study (aGal3, Gal3 and aLam). The labelling index (LI) is the percentage of tissue area specifically stained by a histochemical probe. The mean optical density (MOD) denotes staining intensity. The concentration heterogeneity (CH) feature expresses the concentrational spread of individual fields. The data obtained in the present study show that: (i) white matter of a non-tumoural brain expresses galectin-3 (and also galectin-3-binding sites); (ii) the level of galectin-3 expression significantly decreases in the majority of tumour astrocytes from low to high grade astrocytic tumours; while (iii) some tumour cell clones expressing high amounts of galectin-3 emerged with increasing levels of malignancy; and (iv) the level of accessible galectin-3-binding sites was apparently not heavily modified in the course of malignancy progression. In conclusion, the results obtained in the present study show that human astrocytic tumours are very heterogenous in their galectin-3 levels of expression. If high levels of galectin-3 determine the invasiveness potential of a tumour cell, then within a heterogenous tumour the presence of even a small, but actively proliferating number of tumour cell clones expressing high levels of galectin-3 can be expected to lead to tumour invasiveness.

Adult↗

PubMed1999

Galectin fingerprinting in tumor diagnosis. Differential expression of galectin-3 and galectin-3 binding sites, but not galectin-1, in benign vs malignant uterine smooth muscle tumors.

Cell-matrix interactions are governed by a distinct set of proteins, with 2 nonintegrin laminin-binding proteins, galectin-1 and galectin-3, providing 1 aspect. The expression patterns of laminin and the 2 galectins and galectin binding sites were quantitatively determined by means of computer-assisted microscopy with the aim of differentiating between 16 leiomyomas and 10 leiomyosarcomas of the uterus. Three quantitative variables were computed for each of the 5 histochemical markers: labeling index, which describes the percentage of tissue area specifically stained by a given marker; mean optical density which reflects the concentration of the marker; and concentrational heterogeneity, which characterizes the degree of heterogeneity of the marker distribution in the tumor tissue areas. The results reveal evident differences in the galectin-3-related parameters in the 2 tumors groups. Whereas the concentration of galectin-3 binding sites was significantly (P = .01) weaker in the leiomyosarcomas than in the leiomyomas, the percentages of tumor tissue expressing galectin-3 (P = .02) and its binding sites (P = .002) were significantly higher in the leiomyosarcomas than in the leiomyomas. Although significantly (P = .02) higher, the concentration of laminin was more heterogeneously distributed (P = .01) in the leiomyosarcomas than in the leiomyomas. In contrast, the levels of expression of galectin-1 and its accessible binding sites remained similar for both the leiomyomas and the leiomyosarcomas. Finally we document how the levels of expression of galectin-3 and its binding sites can be of assistance in reliably differentiating leiomyomas from leiomyosarcomas.

Adult↗

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↗