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S Garbisa

Publications and source records attributed to S Garbisa.

At least 55 records · Page 3Linked to original sources
PubMed1992

Adhesion of 8701-BC breast cancer cells to type V collagen and 67 kDa receptor.

Ductal infiltration carcinomas (d.i.c.) of the breast are potentially highly metastatic tumours, associated with drastic alterations of the architecture and molecular composition of the extracellular matrix at the tumour-host interface. 8701-BC, a recently characterized cell line, isolated from primary d.i.c., was used to study different aspects of tumor cell-substratum interactions. Since type V collagen deposition is augmented in d.i.c. we have examined the ability of 8701-BC cells to interact with this collagen species. We have found that cell binding to type V collagen was mediated by protein homologous to the 67 kDa laminin receptor (67-R). This conclusion is substantiated by the following observations: (a) a major band having an apparent molecular mass of 67 kDa and immunoreactive to the anti-67 R antibody was detectable by SDS-PAGE of the membrane proteins; (b) the antibody inhibited cellular adhesion to type V collagen in a dose-dependent way; (c) membrane proteins purified by affinity chromatography on type V collagen were immunoreactive to anti-67 R antibody, but not to anti-VLA1, VLA2 and VLA3 integrin antibodies. This receptor appears to have prominent carbohydrate-binding properties, since lactose competes with cell adhesion to type V collagen.

Animals↗
PubMed1992

[Collagenase IV and laminin receptors in cultured trophoblast cells].

Human trophoblast cells were obtained from a term placenta and cultured through several stages. Using specific antibodies marked using an avidin biotin system and given the characteristic "invasiveness" of placental tissue, the Authors investigated the possible presence of those markers which have been found to be correlated with invasive and metastatic tumour cells. The positivity shown by cultured trophoblast cells towards laminin receptors and collagenase IV may have important implications which might explain the strange formation and maintenance of the human uteroplacental circulation in which embryonal tissue is in direct contact with maternal blood.

Cells, Cultured↗
PubMed1991

Laminin receptors, collagenase IV and prognosis in node-negative breast cancers.

In 187 node-negative breast cancers, the expression of laminin receptors and collagenase IV was directly related in 52% of cases, independently of pathological (tumor size and histology) and biological (estrogen receptors and proliferative activity) features. Moreover, the presence of laminin receptors and collagenase IV did not appear to influence tumor proliferative activity, evaluated as 3H-thymidine labelling index. In this case series, relapse-free survival and overall survival at 6 years were significantly affected by tumor size, hormone receptor status and proliferative activity. Conversely, high levels of laminin receptors and collagenase IV failed to influence relapse-free or overall survival, whereas they were strong indicators of local-regional diffusion of the disease.

Biomarkers, Tumor↗
PubMed1991

Increased expression of the laminin receptor in human colon cancer.

It has been proposed that among the various cell-surface proteins capable of interacting with laminin, the 67-kd high-affinity laminin receptor plays a crucial role during tumor invasion and metastasis. In this study, the expression of laminin-receptor-precursor messenger RNA (mRNA) and 67-kd protein was analyzed in human colon adenocarcinoma. In 22 of 23 patients with colon cancer, we found a 2- to 23-fold increase in levels of laminin-receptor-precursor mRNA in the cancer tissues compared with those in matched normal adjacent colonic mucosa. In 10 of 11 cases studied, the level of 67-kd laminin receptor, detected by affinity-purified anti-laminin-receptor synthetic peptide antibodies on immunoblots of matched tumor and normal tissue extracts, was higher in the colon carcinoma tissue. Immunodetection of laminin receptor in tissue sections using anti-laminin-receptor-peptide antibodies confirmed that the increased expression of laminin receptor was specifically associated with the cancer cells. In a series of 72 paraffin sections of colon lesions, we observed a correlation between the expression of the laminin receptor and the Dukes' classification. Our observations indicate that increased expression of laminin-receptor-precursor mRNA is associated with enhanced levels of the 67-kd laminin receptor as well as with the invasive phenotype of colon carcinoma. Detection of this metastasis-associated gene product may be a valuable adjunct in the evaluation of human colon cancer.

Adenocarcinoma↗
PubMed1991

Increased expression of the Mr 72,000 type IV collagenase in human colonic adenocarcinoma.

Proteolytic enzymes, such as type IV collagenase, play an important role in tumor invasion and metastasis. To examine Mr 72,000 type IV collagenase expression in human colon carcinoma, blot hybridization of total RNA from 19 primary colon tumors were performed. These filters were probed with complementary DNA probes encoding the Mr 72,000 type IV collagenase metalloenzyme. The results were expressed as the ratio of the messenger RNA (mRNA) levels in the tumor tissue to that in the adjacent normal mucosa (R). The level of the 3.1-kilobase type IV collagenase mRNA was higher in the primary tumor than in the normal adjacent colonic mucosa in 13 of 18 (72%) cases with a diagnosis of adenocarcinoma. These cases were divided into high expression (R, 4.50 to 29.34) and intermediate expression (R, 2.54 to 3.31) subgroups. Both groups showed statistically significant (P less than 0.05) elevations when compared with the five cases showing the lowest levels of Mr 72,000 type IV collagenase mRNA expression (low expression subgroup; R, 0.96 to 1.48). With this demonstrated elevation of Mr 72,000 type IV collagenase mRNA in colorectal adenocarcinoma we examined concomitant expression at the protein level using immunohistochemical techniques. Immunohistochemical examination of 70 cases of colon tumors, including 30 benign adenomas, using anti-Mr 72,000 type IV collagenase antibodies demonstrated a significant correlation with Duke's classification (P less than 0.001). Our results suggest that enhanced expression of the Mr 72,000 type IV collagenase enzyme may be a marker of human colorectal tumor invasiveness.

Adenocarcinoma↗
PubMed1991

Alveolar macrophages from patients with AIDS and AIDS-related complex constitutively synthesize and release tumor necrosis factor alpha.

To verify the hypothesis that alveolar macrophages (AMs) from patients infected with HIV-1 could synthesize and release TNF alpha, AMs recovered from the BAL fluid of 11 patients with seropositive HIV-1 (six with AIDS and five with ARC) were tested in vitro for their ability to destroy TNF alpha-susceptible targets. Furthermore, the presence of TNF alpha was assessed in AM-conditioned supernatants on the basis of their cytotoxic activity and by using an immunoenzymatic test and immunoblotting. Transcription of the TNF alpha gene in AMs was also studied by means of the Northern blot analysis. AMs freshly recovered from patients infected with HIV-1 exhibited high levels of cell-mediated cytotoxicity against U937 targets, and the addition of a polyclonal anti-TNF alpha antibody resulted in a significant inhibition of the target lysis. Cell-free supernatants conditioned by unstimulated AMs exerted high levels of cytotoxic activity against TNF alpha-sensitive targets, whereas duplicate, neutralization experiments performed in the presence of an anti-TNF alpha antibody proved that the observed cytotoxic activity was mostly mediated by TNF alpha. The presence of high amounts of TNF alpha in the conditioned media was confirmed by the immunoenzymatic test. In addition, the immunoblot analysis showed that the TNF alpha released by AMs has a Mr 17,000 band, identical to a standard preparation of recombinant TNF alpha. The Northern blot demonstrated that unstimulated AMs express detectable levels of mRNA transcripts for TNF alpha. Taken together, our data support the concept that AMs from patients with HIV-1 infection constitutively release TNF alpha.(ABSTRACT TRUNCATED AT 250 WORDS)

AIDS-Related Complex↗
PubMed1991

Augmentation of type IV collagenase, laminin receptor, and Ki67 proliferation antigen associated with human colon, gastric, and breast carcinoma progression.

The proportion of neoplastic cells immunocytochemically positive for type IV collagenase (IVase), laminin receptor (LR), and Ki67 proliferation-associated antigen increased during the progression of human colon, gastric, and breast carcinomas. Thirty cases of colonic adenoma were compared with 30 cases of Dukes' A or B stage carcinoma and ten cases of Dukes' C stage carcinoma. The percentage of positive cells increased significantly (P less than 0.001) for all three antigens comparing carcinomas with adenomas and Dukes' C stage compared with Dukes' A/B stage. The same pattern of antigen correlation with progression was found with 40 human gastric carcinomas. Gastric carcinomas classified as well-differentiated advanced stage contained a significantly higher proportion of tumor cells positive for IVase (P less than 0.001), LR (P less than 0.001), and Ki67 (P less than 0.001) compared with well-differentiated superficial tumors. Gastric carcinomas classified as poorly differentiated superficial had a significantly higher proportion of cells positive for Ki67 (P less than 0.016), but not IVase (P less than 0.069) or LR (P less than 0.075), compared with poorly differentiated advanced tumors. Metastasis of colon and gastric carcinoma retained the immunostaining pattern of the primary tumors. Thirty cases of breast neoplasia were compared with 30 adjacent samples of normal duct epithelium. A positive correlation (P less than 0.001) was found for the immunoreactivity of all three antigens in the invasive carcinomas compared with the normal epithelium. Invasive ductal carcinoma and invasive lobular carcinoma had a significantly higher percentage of immunoreactivity for the three antigens compared with corresponding in situ lesions.(ABSTRACT TRUNCATED AT 250 WORDS)

Breast Neoplasms↗
PubMed1991

[Changes in myocardial collagen in spontaneously hypertensive rats (SHR)].

The aim of this study was to evaluate whether left ventricular hypertrophy in spontaneously hypertensive rats (SHR) is accompanied by myocardial collagen quantitative and/or qualitative changes. 15 SHR and 20 control normotensive rats (WKR) of three months of age were used. At this age, hypertension has already caused a significant increase in the ratio of the ventricular mass to body weight (mg/g) in hypertensive animals (SHR: 5.11 +/- 0.21; WKR: 3.40 +/- 0.22; p less than 0.001). With respect to body mass, the amount of collagen elicited from the hydroxyproline concentration increases in SHR but remains percentually the same with respect to the biventricular mass. In SHR, changes in the amount of type-1 alpha chains and type-V alpha chains, and the presence of a low molecular weight collagenous fraction have been observed. Moreover, we have found an increase in the ratio of type-1 alpha 1 chains to type-1 alpha 2 chains. This change might be related to the appearance of a type-1 alpha 1 trymer. The presence of such a type-1 alpha trymer and of low molecular weight collagenous fractions may suggest the appearance of fetal collagenous isoforms in ventricular myocardium, due to the increased pressure load as well as to the increased turnover (an index of a remodelling activity of cardiac stroma). These changes might play a role in the transformation of myocardial viscoelastic properties in SHR with a progressive diastolic stiffness of the ventricular wall.

Age Factors↗
PubMed1991

Evaluation of hepatocellular carcinoma aggressiveness by a panel of extracellular matrix antigens.

Invasion and metastasis requires a series of interactions between malignant cells and the extracellular matrix (ECM). Antigen markers that relate to these interactions were evaluated for prognostic correlation in human hepatocellular carcinoma. Basement membrane type IV collagen (cIV), type IV collagenase (cIVase), laminin, and laminin receptors (LRs)--all ECM antigens previously proposed to be modulated in association with tumor aggressiveness--were immunohistochemically investigated in 30 cases of hepatocellular carcinomas (HCCs). The pattern of antigen expression was correlated with 1) 36 months' clinical follow-up and 2) the pathologic grade. As a means of estimating the proliferation fraction, an additional antigen, Ki67, was also studied in this series. There were major differences in the distribution of cIV and laminin, and in the quantity of cIVase-, LR-, and Ki67-positive cells associated with grade and prognosis. A smaller quantity of cIV and laminin and a higher number of cIVase-, LR-, and Ki67-positive cells were detected in the poorly differentiated compared with the well-differentiated HCCs. The tumors with lower immunoreactivity for cIV and laminin components accompanied by a higher number of cIVase-, LR-, and Ki67-positive cells fall into a group with the poorest overall survival (P less than 0.006). The panel of antigens is proposed as a useful prognostic tool for evaluating HCC tumor aggressiveness.

Antigens, Neoplasm↗
PubMed1990

Degradation of immobilized soluble elastin by tumor cells in culture: quantitation by ELISA.

A new, sensitive assay based on the enzyme-linked immunosorbent assay has been developed for measuring elastolytic activity produced by invasive and/or metastatic tumor cells in culture. Elastin peptides, obtained by treating the insoluble protein with either oxalic acid, KOH, or chymotrypsin, are adsorbed onto the surface of cell culture microtiter plastic wells, and incubated with dilution of standard proteinases or viable normal or tumor cells. The total amount of immobilized elastin peptides is revealed by the mean of specific antibodies, and detected by a microplate reader, while dose- and time-dependent reduction of bound antibodies after incubation with proteases or cells is taken as a measure of elastin degradation. Adsorbed elastin has been found to be available as a substrate for purified enzymes, as well as for living melanoma cells (A2058 and B16-BL6), c-Ha-ras transformed rat embryo fibroblasts, and human pulmonary macrophages, as demonstrated by the release into the culture medium of lower molecular weight digestion products. No degradation was achieved by BALB/3T3 and rat embryo control fibroblasts, and no inhibition was produced by the presence of fetal calf serum which, on the contrary, potentiated the degradation by active cells. This new method, revealing degradation of only a few nanograms of soluble elastin peptides, can be used for studying the importance in tissue invasion and metastasis of elastolytic proteinases produced by cells in culture.

Animals↗
PubMed1990

The capsule surrounding primary liver tumors: wherefrom its prognostic significance?

Primary liver neoplasms in cirrhotic and non-cirrhotic patients were studied by electron microscopy and immunohistochemical methods for extracellular matrix (ECM) antigens. A capsule of variable thickness was present in many expanding hepatocellular carcinomas, while it was absent in those of small size, and either fragmented or absent in the infiltrating ones. In the capsules of early onset, fibronectin was the most frequent stromal glycoprotein. In the completely formed capsular structures, fibronectin, type-V collagen and laminin were the most common macromolecules seen. No differences were evident in the pattern of ECM macromolecules in the capsules surrounding hepatocellular carcinomas compared with those found in benign lesions, such as hepatocellular adenomas or focal nodular hyperplasia. The possibility is discussed that the capsule could be a result of the following sequence: tissue with expansive (not infiltrative) growth-mechanical compression-ischemic necrosis of surrounding tissues-repair process with ECM deposition.

Carcinoma, Hepatocellular↗
PubMed1989

Hormonal and basement membrane markers for immunoidentification of cultured human trophoblast cells.

Improvement of human chorionic villi cells in vitro culture has been obtained by supplementing the medium with 30% human fetal cord serum, instead of fetal calf serum. Expression of human chorionic gonadotropin, estrogen and progesterone receptors, laminin, laminin receptors, and type IV collagen has been studied on first subculture passages (4-7 weeks) by immunoperoxidase method. A minority of the cultured cells were positive for estrogen receptors, the majority were positive for progesterone receptors, while all cells were negative for human chorionic gonadotropin. Cultured cells showed variable positive immunostaining for basement membrane markers like laminin, and type IV collagen, and for laminin receptors. Detection of both progesterone receptors and laminin, or type IV collagen, excluded fibroblast contamination and could then be useful for quick identification of cultured trophoblast cells.

Basement Membrane↗
PubMed1989

Pulmonary alveolar macrophages from patients with active sarcoidosis express type IV collagenolytic proteinase. An enzymatic mechanism for influx of mononuclear phagocytes at sites of disease activity.

Alveolar macrophages (AMs) recovered from the bronchoalveolar lavage (BAL) of 44 patients with sarcoidosis were evaluated for their ability to release type IV collagenolytic metalloproteinase (IV-Case). This enzyme, which is produced by peripheral blood monocytes (PBMs) but not by tissue macrophages, degrades type IV collagen, the major structural component of vessel wall basement membranes, and helps to promote the migration of PBMs from the blood compartment to peripheral tissues. Our results demonstrated that AMs from patients with active sarcoidosis released significantly increased levels of IV-Case with respect to patients with inactive disease and control subjects. After in vitro culture, sarcoid AMs secreted IV-Case during the first 24 h of collection; after that time, AMs progressively lost their ability to release IV-Case. Exposition of both sarcoid and normal AMs to recombinant IL 2 or gamma IFN did not influence their property to release IV-Case. The immunoblot analysis of IV-Case demonstrated complete identity between IV-Case released by AMs and the degradative enzyme obtained from PBMs. The increased property to release IV-Case was significantly related to the increase of the absolute number of AMs and, in particular, of AMs bearing two determinants that are usually expressed by most PBMs (CD11b and CD14). Selective depletion of CD11b+/CD14+ AMs from the entire macrophagic population was associated with the recovery of the IV-Case activity to normal values. A positive correlation was also found between the increase in the absolute number of lung T cells and the enhanced CD4/CD8 pulmonary ratio. A 6-mo follow-up study indicated a significant association between the positivity for the 67Gallium scan and the increased property of AMs to release IV-Case. Our data are consistent with the hypothesis that a IV-Case mediated influx of peripheral monocytes takes place in the lung of sarcoid patients. Furthermore, the correlation found between the IV-Case release and disease activity suggests that this assay could represent a useful tool in sarcoidosis disease staging.

Adult↗
PubMed1988

Regulation of the metastatic phenotype by the E1A gene of adenovirus-2.

We have previously demonstrated that rat embryo cells transformed by the ras oncogene alone are both tumorigenic and highly metastatic when injected into nude mice. In contrast, rat embryo cells transformed with the ras oncogene and the adenovirus 2 (Ad2) Ela gene are tumorigenic but either fail to metastasize, or exhibit a very low metastatic potential. Here we demonstrate that transfection of the Ad2 Ela gene into several of the ras transformed rat embryo cell lines results in a dramatic reduction in metastatic potential relative to the parental cell line. Transfection of cDNAs for the 12S and 13S Ela transcripts showed that both gene products are capable of reducing the metastatic potential of the ras transformed cell lines, however the 12S cDNA was more effective. This effect is specific to the Ad2 Ela gene as ras transformed cell lines expressing the Ad12 Ela gene or the human N-myc gene maintained their high metastatic potential. We hypothesize that the Ad2 Ela gene may regulate the expression of one or more cellular genes that contribute to the metastatic phenotype.

Adenovirus Early Proteins↗
PubMed1988

Different metastatic aggressiveness by murine TS/A clones: ultrastructure, extracellular glycoproteins and type IV collagenolytic activity.

Cell ultrastructure, extracellular matrix glycoproteins, and type IV collagenolytic activity have been examined in four murine TS/A clones characterized by different metastatic aggressiveness. In vitro, highly metastatic clones (E) exhibited slightly less differentiated ultrastructure, and high type IV collagenolytic activity, while low metastatic clones (F) showed a more differentiated cytotype, with either high and low collagenolytic activity. Type IV collagen, laminin, and fibronectin were expressed without correlation with the metastatic efficiency; keratin was slightly more evident in E than in F cells. The morphological differences between E and F clones were less evident in the tumors produced by subcutaneous injection, and markedly reduced in the relative metastases composed only of the less differentiated cytotype; differences were also reduced in cells cultured on extracellular-matrix-coated flasks. The present study shows that no general correlation is observed between the studied parameters and metastatic aggressiveness.

Adenocarcinoma↗
PubMed1988

Correlation between differentiation and lung colonization by retinoic acid-treated F9 cells as revealed by the expression pattern of extracellular matrix and cell surface antigens.

For study of the correlation between differentiation and organ colonization properties of tumor cells, F9 embryonal carcinoma (EC) cells were treated with retinoic acid, an inducer of differentiation; and their organ colonization pattern was assessed by the experimental metastasis assay. Untreated cells were found to colonize the liver, whereas treated cells colonized the lungs. This pattern held true when metastases were scored after spontaneous death or after a careful microscopic search for micrometastases. Histologic examination revealed that both the tumor nodules produced by the untreated and the treated cells had the characteristics of EC devoid of any evidence of differentiation. The immunohistochemical study of the expression of markers typical of embryonal carcinoma cells or of the extracellular matrix components laminin and collagen type IV, typical of differentiated cells, confirmed these results. However, the lack of expression of stage-specific embryonal antigen 1 (SSEA-1), a marker generally associated with the undifferentiated state, observed only in the tumors obtained after injection of treated cells, indicates that the lung nodules probably derive from cells that have responded to the induction in vitro but have dedifferentiated in vivo.

Animals↗