Effects of culture passages on collagen immunostaining in human dental pulp and gingival fibroblasts.

In this study, a scanning microscopic computer-assisted image analysis system was used for the immunocytochemical characterisation of collagen types I, III and V in normal human fibroblasts from pulp and gingival explants, using specific purified antibodies and peroxidase labeling. The culture conditions were standardized in order to evaluate simultaneously the expression of the three antigens in four different culture passages of the two fibroblast types. The optical density values of immunostaining intensities were quantified, the integrated optical density per cell was calculated, and the results were analyzed by a variance test. It was found that all three collagen types were present in the tissues, and in both gingival and pulp fibroblasts after three to nine culture passages. A non-parametric statistical analysis of the staining intensity variances revealed significant differences between antigenic levels depending on the tissue origin of the fibroblasts and an effect of culture passages. The results seemed to justify application of this technique at the light microscope level for the evaluation of collagen production, the principal function of fibroblasts, but the tissue origin and number of culture passages should be taken into consideration for in vitro biocompatibility testing of dental materials.

[Laser therapy in the prevention and treatment of mucositis caused by anticancer chemotherapy]. / La laserthérapie dans la prévention et le traitement des mucites liées à la chimiothérapie anticancéreuse.

The appearance of mucositis is a frequent and painful secondary effect of anticancer chemotherapy. Patients who develop oral toxicity during the first course of treatment will almost assuredly show identical side effects during each subsequent course unless the drugs are changed or the doses are lowered. In the absence of an efficacious antidote or preventive prophylaxis for such lesions to date, this report presents the results of a preliminary retrospective non-randomized study of the effect of soft-laser treatments on mucositis in cancer patients receiving combination chemotherapy, including 5-fluorouracil. Iatrogenic mucositis was observed during 43% of 53 chemotherapy cycles in the case control population. Curative laser therapy reduced the time to repair lesions and the rate of therapeutic modifications. For patients who received soft-laser therapy as a preventive measure, the incidence of oral complications was reduced to 6% during 101 cycles of chemotherapy. All of these patients, even those who have encountered mucositis before receiving preventive laser therapy, terminated their cancer therapy as originally scheduled. Well designed and carefully controlled trials will be necessary to define the place of helium-neon laser therapy in the repair and prevention of oral complications due to cancer chemotherapy.

Relationship between cathepsin D, urokinase, and plasminogen activator inhibitors in malignant vs benign breast tumours.

The concentrations of cathepsin D (Cath D), urokinase (uPA) and two plasminogen activator inhibitors (PAI-1 and PAI-2) were analysed in the cytosols of 130 human mammary tumours (43 benign tumours and 87 primary and unilateral breast carcinomas). uPA, PAI-1 and PAI-2 levels were measured by antigenic immunoassays and Cath D by immunoradiometric assay. The median levels of the four parameters were significantly higher in the malignant tumours than in the benign ones. Cath D and uPA increases were 4-fold and 5-fold respectively. PAI-1 and PAI-2 increases were much more important, 74-fold and 29-fold respectively. In malignant tumours, median levels of Cath D and uPA did not vary according to classical prognostic factors (histologic grade, presence or absence of axillary lymph nodes, steroid receptors, UICC stage, tumour size, age, and menopausal status). However, PAI-1 decreased in ER+ and PR+ tumours and PAI-2 increased in menopausal women's tumours. When Cath D, uPA, PAI-1 and PAI-2 levels in malignant tumours were compared, positive correlations were found for all combinations. The implication of plasminogen activator inhibitors in the phenomenon was surprising and merits further investigation using tools other than global antigen measurements in tumours.

Modulation of tPA, PAI-1 and PAI-2 antigen and mRNA levels by EGF in the A431 cell line.

It has been reported that EGF treatment enhances uPA but not tPA in the A431 epidermoid carcinoma cell line. To determine whether the absence of tPA modulation by EGF could be due to the action of inhibitors, we assayed tPA, PAI-1, PAI-2 and tPA/PAI-1 complexes by immunological assays and zymography in A431 serum-free medium. We found that, under conditions in which EGF had no effect on tPA activity, tPA antigen increased with a concomitant rise of tPA/PAI-1 complexes, indicating the action of an inhibitor. Both tPA antigen and tPA/PAI-1 complexes were modulated by EGF in a time and concentration dependent manner. tPA/PAI-1 complex levels were lower than tPA levels, suggesting the presence of other inhibitors. Immunological assays detected PAI-2 in addition to PAI-1 and showed a time and dose response to EGF. Modulation of tPA and the anti-activators by the growth factor was confirmed by identification of the corresponding transcripts with cDNA probes. We conclude that the net plasminogen activator activity in A431 cells is the result of a balance between activators and inhibitors.

Concomitant secretion by A431 cells of tissue plasminogen activator and a specific inhibitor masks EGF modulation of tPA activity.

It has previously been reported that EGF enhances uPA but not tPA in the A431 squamous carcinoma cell line. To determine whether the absence of tPA modulation by EGF reflected steady levels or the action of an anti-activator, we assayed tPA, PAI-1 and tPA/PAI-1 complexes by zymography and immunological assays. Under conditions in which EGF had no effect on tPA activity, tPA antigen paradoxically increased with a concomitant rise of tPA/PAI-1 complexes. This indicated that tPA was rapidly inactivated through the formation of a complex, immunologically and electrophoretically related to tPA/PAI-1. tPA antigen and tPA/PAI-1 complexes were modulated by EGF in a time and concentration dependent manner. PAI-1 antigen was secreted into A431 medium (CM) after a lag phase of 16 h in both control and EGF-treated cultures. Evidence is presented here that two forms of PAI-1 are present in A431 CM: an inactive form and an active form which neutralizes the tPA secreted, masking its enhancement by EGF in functional assays.

Helium-neon laser treatment transforms fibroblasts into myofibroblasts.

The differentiation of myofibroblastic cells from normal human gingival fibroblasts in vitro has been established by transmission electron microscopy and quantitated by immunohistochemistry, using antigelsolin monoclonal antibodies. Untreated control cultures were compared to cultures exposed to Helium-Neon (He-Ne) laser irradiation. A direct and massive transformation of the cultured fibroblasts into myofibroblasts was observed as early as 24 hours after laser treatment, whereas control cultures were comprised of only resting fibroblasts and active fibroblasts. This in vitro induction of myofibroblasts may be analogous to that which occurs in vivo. Therefore we undertook a similar study using biopsies from gingival tissues after wisdom tooth extraction. Myofibroblasts were present in the connective tissue of laser-treated gums 48 hours after irradiation, but not in untreated contralateral control tissues. These data provide evidence that the primary biologic effect of the Helium-Neon laser on connective tissue is the rapid generation of myofibroblasts from fibroblasts. The induction of a phenotype with contractile properties may have clinical significance in the acceleration of the wound-healing process.

[Evaluation of the cytotoxicity of two capping materials: in vitro cell culture study]. / Evaluation de la cytotoxicité de deux matériaux de coiffage: étude in vitro sur culture cellulaire.

Evaluation of the biocompatibility of a crown reconstruction material in vivo on human teeth by histologic observation of pulpal reactions is a long lasting and expensive procedure. Before to start it, a first examination can be done by testing the material on cell cultures. If the used culture cells contain antibiotics, it is necessary to combine these tests with a bacteriologic examination of the tested material. Two calcium hydroxide containing materials for dentin-pulp capping, were submitted to cytotoxicity tests using human pulpal fibroblasts cultures. The cytotoxicity of one over the two materials could be related to its lability and bacterial contamination.

Toward a new approach in tumor cell heterogeneity studies using the concept of order.

A new methodology was developed to study dynamic processes topographically in biological systems by means of a graph-theoretical method. It is based upon order parameters obtained from a minimal spanning tree analysis coupled with computer simulations. The method was used to analyse the heterogeneous behavior of two neoplastic cell lines after treatment with laminin. The laminin-induced cell detachment was quantitated and shown to be inversely related to cell population density and thus to cellular interactions. Our statistical analysis is a very powerful tool to obtain information from seemingly disorderly heterogeneous biological models.

Modulation of plasminogen activator systems by matrix components in two breast cancer cell lines: MCF-7 and MDA-MB-231.

We have analyzed the plasminogen activator (PA) systems of two metastatic breast adenocarcinoma cell lines, MCF-7 and MDA-MB-231, as a function of 17 beta-estradiol stimulation when the cells were cultured on purified components of extracellular matrix. Laminin enhanced PA levels in both cell lines, but this enhancement seemed to occur via different mechanisms, including dissociation of inhibitor complexes. The major effect was the marked increase in cell-associated urokinase-type PA (u-PA); the increase was independent of estrogen in hormone-insensitive MDA-MB-231 cells grown on laminin-coated surfaces. In estrogen-sensitive MCF-7 cells, 17 beta-estradiol stimulated u-PA secretion in a similar fashion on plastic, laminin, fibronectin, or collagen but acted in synergy with laminin in the production and release of tissue-type PA.

[Dosage and modulation of cutaneous steroid receptors during antihormonal therapy in a case of Stewart-Treves syndrome]. / Dosage et modulation des récepteurs stéroïdiens cutanés sous thérapeutique anti-hormonale dans le cas d'un syndrome de Stewart-Trèves.

We report a case with clinical symptoms of a Stewart-Treves syndrome 2 years after homolateral mastectomy for carcinoma. The mammary origin of the syndrome was found at histology and confirmed by assays of hormone receptors in skin biopsies before and during anti-hormone therapy. This treatment rapidly attenuated the clinical signs of both the lymphedema and the pseudo-Kaposi cutaneous lesions. Hormone receptor determinations are suggested as useful tools for the diagnosis and for surveillance of therapeutic efficacy. CASE HISTORY. This 68-year old patient whose right breast was removed in April, 1985 for scirrhous carcinoma was hospitalized in February, 1987 for lymphedema, pain and functional impotence of the right arm accompanied by Kaposi-like skin lesions in the homolateral mammary region, the right shoulder and the upper third of the right arm. Tamoxifen administration in doses of 30 mg/day was started on the day of the first biopsies at sites of the cutaneous lesions and continued for 60 days. Additional biopsies were taken on days 30 and 60 of therapy. Under therapy clinical improvement was noted with decrease in the lymphadenopathy and in the size of the nodular skin lesions. PATHOLOGY AND STEROID HORMONE ASSAYS. Standard histological studies were performed on one of the biopsies. The remaining tissues were flash frozen and assayed for estrogen and progesterone receptors. ER was determined by radio-ligand assay (RLA) to measure the free binding sites of the hormone or anti-hormone and by enzyme immunoassay (EIA) to detect both free and occupied antigenic sites.(ABSTRACT TRUNCATED AT 250 WORDS)

[Breast tissue: estrogen receptors. Immunohistochemical and biochemical analysis of normal and hyperplastic tissue and carcinoma in situ. Apropos of 86 cases]. / Tissu mammaire: récepteurs estrogéniques. Analyse immunohistochimique et biochimique du tissu normal, hyperplasique et du carcinome in situ. A propos de 86 cas.

Estrogen receptors (ER) were investigated using immunohistochemical techniques in 54 cases and biochemical techniques in 38 cases on a series of biopsy specimens of normal, hyperplasic and malignant mammary tissue (intraductal carcinoma). Immunohistochemical data were submitted to quantitative and semi-quantitative analysis (SAMBA 200, TITN). On normal tissue, immunostaining is bright and evenly distributed in galactophores and ductulo-lobular junctions; it is unevenly distributed but consistently present in lobules and increasing after menopause. On hyperplasic tissue, immunostaining of papillary cystadenomas and epitheliosis and fibroadenosis zones was similar to normal tissue with respect to the intensity and heterogeneity. Conversely, their immunohistochemical features are close to blunt duct adenosis and atypical lobular hyperplasia of ductulo-lobular junctions. On malignant tissue, immunostaining is unpredictable, it can be evenly distributed, unevenly distributed in patches or gradients, or totally absent. Immunohistochemical techniques can only be used to assess the intensity and distribution of ER in function of cell type in normal tissue and during a cancerous process. Thus strong receptivity of ductulo-lobular junctions may reinforce the claim that these structures are the targets for estrogen co-carcinogenic substances. The heterogeneity of ER at the onset of carcinoma suggests the possibility of several pathway of development. The fact that myoepithelial cell never seem to display estrogen type receptivity makes it logical to seek a special sensitivity for them.

Estradiol membrane binding sites on human breast cancer cell lines. Use of a fluorescent estradiol conjugate to demonstrate plasma membrane binding systems.

A fluorescent estradiol macromolecular complex was used to study and to characterize steroid binding to membranes of living target cells. Ligand binding to plasma membranes was quantitated with a sensitivity of 0.1 nM. In this way, we found two types of estradiol-binding sites on hormone sensitive MCF-7 cells. Type A sites (8000-16000 sites per cell) were rapidly saturated at low concentrations of the estradiol-bovine serum albumin-fluorescein isothiocyanate macromolecular complex (E2-BSA-FITC). They had a greater affinity for the complex than did the type B sites for which a phenomenon of cooperative fixation was shown. The complex binding was displaced by estrogenic molecules, but not by non-estrogenic compounds, such as cortisol or progesterone. We also studied complex binding on another breast cancer cell line, MDA-MB-231 (MDA), without intracellular estrogen receptors. These cells showed a specific plasma membrane binding system for estrogen, but lacked the high affinity type A binding site. Then, we report the effects of enzyme treatments (trypsin, phospholipase A2 and neuraminidase) on E2-BSA-FITC binding to MCF-7 cell membranes. The quantity of complex bound to membranes decreased after phospholipase and neuraminidase treatments and increased after trypsin. But, in the three cases, the binding was no longer specific because it could not be displaced by E2-BSA or by estradiol. The enzymatic effects were reversible and specific binding was totally restored within 24 h. However, in the presence of the protein synthesis inhibitor, cycloheximide, no restoration of specific binding occurred on trypsin-treated cells. Estrogen binding to MCF-7 and MDA cell plasma membranes thus possesses the three characteristics of all mediated transport processes across biological membranes: saturability, substrate specificity, and specific inhibition. However, the high affinity type A binding site was found only on the estrogen-sensitive cell line, MCF-7.

Early alterations at the plasma membrane of breast cancer cell lines in response to estradiol and hydroxytamoxifen.

The time course of the early stage of estradiol-17 beta (E2) and hydroxytamoxifen (OHTAM) action at the plasma membrane of hormone-responsive MCF-7 and non-responsive MDA-MB-231 (MDA) breast cancer cell lines was investigated using scanning electron microscopy (SEM), electron probe X-ray microanalysis and microelectrophysiology analysis. SEM showed a marked increase in the density and the length of microvilli (MV) on MCF-7 cells treated with 1 nM estradiol for 1 min. This membrane response disappeared at 5 min. No early effect was obtained with OHTAM, but both compounds produced a similar surge of heterogeneous MV at 15 min of treatment. The morphological change induced by E2 subsided at 60 min, whereas that of OHTAM persisted. X-ray microanalysis and computer determination of peak/background ratios permitted the demonstration that these morphological alterations were concomitant with a rise in the intracellular level of potassium. Microelectrophysiology analysis showed a sharp transitory decrease in the membrane potential of MCF-7 cells in response to estradiol. In the estrogen-insensitive MDA cells, the hormone did not modify the membrane potential and K levels decreased at 1 and 5 min before rising again to control levels at minute 15 when MV appeared. With OHTAM, potassium decreased significantly at 60 min of treatment. These initial and transitory changes in surface morphology paralleled by alterations in potassium level may be consistent with the occurrence of estrogen membrane receptors on target cells, a new aspect of steroid hormone action.

Estrogen receptor immunocytochemical assay (ER-ICA): computerized image analysis system, immunoelectron microscopy, and comparisons with estradiol binding assays in 115 breast carcinomas.

An estrogen receptor (ER) immunocytochemical assay (ER-ICA) was applied to 115 malignant breast carcinomas and the results were compared to those of steroid binding assays performed on cytosol extracts of the same tumors. Immunoperoxidase (peroxidase-antiperoxidase) staining was performed on frozen sections using rat monoclonal antibody to estrogen receptor H222SP gamma. A preembedding method was used for the immunoelectron microscopy study. A semiquantitative analysis and a computerized image analysis system (SAMBA 200 TITN) were used to evaluate the positive ER immunostaining. Positive immunostaining (81 of 115) was always located in the nucleus of tumor cells and of normal cells in adjacent breast tissue. The immunostaining pattern differed from one tumor to another, due to variations in either the intensity or the percentage of positive cells. When immunohistochemical staining was correlated to biochemical assay, there was an 88% correlation, and staining intensity and percentage of positive cells significantly increased (P less than 0.01) with cytosolic ER levels and were independent of cellularity. These results indicated that ER-ICA is to date the most reliable histochemical method for ER detection and correlated in 88% of the cases with ER biochemical assay; ER-ICA constitutes a method particularly valuable to screen ER negative tumors on condition that tumor fragment quality (sampling and storage) is perfectly controlled; ER-ICA provides additional information for heterogeneous ER distribution within tumors; ER-ICA as a qualitative method is unable to replace the quantitative ER determination obtained with biochemical assay although the computerized system (SAMBA 200) for image analysis of microscopic preparations constitutes a valuable improvement of immunostaining analysis; and ER-ICA based on ER antigenic site detection is complementary to biochemical assay based on ER functional site determination.

Immunohistochemical detection of laminin in 98 human breast carcinomas: a light and electron microscopic study.

The distribution of laminin was studied in 98 breast carcinomas with antilaminin and the avidin-biotin-peroxidase complex method. Laminin was observed within vascular and epithelial basement membranes. Laminin displayed a continuous linear pattern in intraductal carcinomas, and it was heterogeneously distributed, with a discontinuous linear pattern, in invasive carcinomas. No intracellular laminin staining was detected. Electron microscopic study showed laminin immunostaining in the lamina densa of basement membranes in nonneoplastic breast tissue. In tumors, laminin immunostaining frequently revealed multilayered basement membranes and abnormal multilayered basement membranes in blood vessels in the tumor stroma. These data suggest that laminin immunostaining, as a new approach to the heterogeneous basement membrane changes occurring in carcinomas, should permit better understanding of cell diffusion processes and of stroma-tumor cell interactions. The consistent extracellular distribution of laminin in contact with the stroma indicates that the latter plays an important role in the assembly of basement membrane components.

Estrogen receptor immunocytochemical assay (ERICA) and laminin detection in 130 breast carcinomas and computerized (Samba 200) multiparametric quantitative analysis on tissue sections.

An estrogen receptor immunocytochemical assay (ER-ICA) was applied to 130 malignant breast carcinomas and the results were compared to those of steroid binding assays performed on cytosol extracts of the same tumors. Also laminin (lam) distribution was studied in the same tumors. A semi quantitative analysis and a computerized image analysis system (SAMBA 200 TITN) were used to evaluate the positive ER and lam immunostaining. Positive ER immunostaining was always located in the nucleus of tumor cells and of normal cells in adjacent breast tissue. When immunohistochemical staining was correlated to biochemical assay there was a 88% correlation staining intensity and percentage of positive cells significantly increased (p less than 0.01) with cytosolic ER levels. Lam was observed within vascular and epithelial basement membranes (BMs). Lam staining displayed a continuous linear pattern in intraductal carcinomas or was heterogeneously distributed with a discontinuous linear pattern in invasive carcinomas. No intracellular lam staining was detected. In tumors, laminin immunostaining revealed often multilayered BMs and abnormal multilayered BMs in blood vessels in the tumor stroma. These results indicated that (ER-ICA) is to date the most reliable histochemical method for ER detection and correlated in 88% of the cases with ER biochemical assay ER-ICA provides additional information for heterogeneous ER distribution within tumors ER-ICA as a qualitative method is unable to replace the quantitative ER determination obtained with biochemical assay ER-ICA based on ER antigenic site detection is complementary to biochemical assay based on ER functional site determination laminin immunostaing constitutes a new approach to the heterogeneous BM changes occurring in carcinomas, and permits a better understanding of cell diffusion processes and of stroma-tumor cells interactions: the consistent extracellular lam distribution in contact with the stroma, indicates that the latter plays an important role in the assembly of BM components the SAMBA 200 permits a reliable accurate evaluation of the percentage of the immunostained cells and surfaces.

Estrogen receptor immunocytochemical assay (ER-ICA) in human endometrium.

An estrogen receptor immunocytochemical assay (ER-ICA) was applied to 15 tissue samples from human endometrium: five proliferative, five secretory, three carcinomas, and two atypical hyperplasias. A monoclonal anti-ER (H 222 SP gamma, Abbott Lab.) and peroxidase antiperoxidase method were applied on frozen sections, 5 micron thick for light microscopy (LM), 100 micron thick for electron microscopy (preembedding). Positive ER staining was quantitated on tissue sections (LM) using a computerized system of image analysis referred to as SAMBA 200 (Thomson TITN). Positive immunostaining was observed in the nuclei of both epithelial and stromal cells in normal and disordered endometrium. SAMBA 200 quantitative analysis permitted an accurate quantification of ER-positive staining. From this preliminary study it is concluded that (a) ER-ICA constitutes a reliable method to study the ER heterogeneous distribution in tissues and the precise intracellular ER localization, which is not feasible by ER biochemical binding assays; (b) SAMBA 200 analysis of the immunostained tissue sections permits an accurate and reproducible method of evaluating the results to quantitate the staining intensity and to determine the percentage of positive cells and the distribution of positive staining of the various tissue structures (glands and stroma).