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Biomedical subjects

A Sacchi

Publications and source records attributed to A Sacchi.

At least 19 recordsLinked to original sources
PubMed1992

Inhibition of leukemia cell proliferation by receptor-mediated uptake of c-myb antisense oligodeoxynucleotides.

Exposure of human leukemia HL-60 cells to an oligodeoxynucleotide complementary to an 18-base sequence (codons 2-7) of c-myb-encoded mRNA has previously been shown to result in inhibition of cell proliferation. Because HL-60 cells express high levels of transferrin receptor we adapted a DNA delivery system based on receptor-mediated endocytosis to introduce myb oligomers complexed with a transferrin-polylysine conjugate into those cells. A DNA.RNA duplex resistant to S1 nuclease digestion was detected as early as 12 hr after culture of HL-60 cells in the presence of the myb antisense/transferrin-polylysine complex. Exposure of HL-60 cells to the myb antisense/transferrin-polylysine complex resulted in rapid and profound inhibition of proliferation and loss of cell viability much more pronounced than that occurring in cells exposed to free myb antisense oligodeoxynucleotides. The transferrin-polylysine/myb sense complex or the transferrin-polylysine conjugate alone had no effect on HL-60 cell proliferation and viability. These findings indicate that myb synthetic oligodeoxynucleotides enter efficiently into HL-60 by transferrin receptor-mediated endocytosis and exert a profound biological effect. Such a delivery system could exploit other ligand-receptor interactions for the selective delivery of oncogene-targeted antisense oligodeoxynucleotides.

Antineoplastic Agents↗
PubMed1992

Localization and characterization of human salivary kininases.

The human saliva of normal subjects containing large amounts of basic carboxypeptidase produces decarboxylated non inflammatory peptides, for instance, kinins and anaphilotoxins C3a, C4a and C5a. A reduction of epithelial cell-bonded enzyme (carboxypeptidase M-type or kininase I), produces inflammations by the active intact kinins and the initiation of the alternative activating pathway of complement by active anaphilotoxins, which generate complement cleavage products, containing potential destructive mechanism.

Complement System Proteins↗
PubMed1991

Differential expression of transforming growth factor-beta 1 gene in 3LL metastatic variants.

In vitro and in vivo metastatic variants derived from Lewis lung carcinoma (3LL) were examined for the level of the expression of several growth-regulated genes, oncogenes, and transforming growth factor (TGF) genes. To determine whether the proliferative advantage of metastatic cells is due to an increased growth fraction of the cell population or to a deregulated expression of some growth-regulated genes, the mRNA levels of the S-phase-specific H3 histone gene were compared with that of some cell cycle-related genes (vimentin, calcyclin, c-myc, and p53) and oncogenes (Ki-ras, Ha-ras, c-sis, c-src, c-fes, and c-erb). In addition, to evaluate whether an autocrine pattern of cell proliferation is responsible for the proliferative advantage of metastatic cells, the level of the expression of TGF genes (alpha and beta 1) was studied. Northern blot analysis demonstrated that in 3LL metastatic variants the expression of TGF-alpha as well as the expression of all growth-regulated genes and oncogenes studied are similar. Only the TGF-beta 1 gene is expressed at higher levels in highly metastatic 3LL variants maintained either in vitro or in vivo. Data suggest that the proliferative advantage of 3LL metastatic cells is not due to a deregulated expression of some growth-regulated genes and oncogenes, but more likely is acquired through the expression of genes which might interfere with the ability of the tumor cells to escape hostile microenvironmental conditions.

Animals↗
PubMed1991

Research on heterocyclic compounds. XXVIII. Imidazo[1,2-c]pyrimidines.

A group of 24 imidazo[1,2-c]pyrimidines was taken into consideration in order to study their relationships between chemical structure and antiinflammatory activity. Some of these compounds were synthesized by us in the past, the others have been synthesized and characterized to complete the series. Antiinflammatory, analgesic, antipyretic and gastric ulcerogenic activities of such compounds were compared with those of indomethacin and discussed in terms of the effects exerted by the presence on the heterocyclic system of various substituents and an acidic or nonacidic moiety.

Acetates↗
PubMed1990

Integrin (alpha 6/beta 4) expression in human lung cancer as monitored by specific monoclonal antibodies.

In this study, the expression of the alpha 6/beta 4 integrin complex was analyzed in human lung carcinomas both in vitro and in vivo, using two monoclonal antibodies which recognize the integrin subunits alpha 6 (Mab 135-13C) and beta 4 (Mab 439-9B). Immunoprecipitation patterns obtained from established human lung carcinoma cell lines demonstrated that the alpha 6 and the beta 4 subunits were differentially expressed in carcinomas of different types. The alpha 6 subunit was expressed in all the cell lines tested (squamous cell carcinoma A431, adenocarcinoma A549, large cell carcinoma DG3, and small cell carcinoma AE2). The beta 4 subunit was expressed in non-small cell cancer lines but was not detectable in the small cell cancer line tested. Using a quantitative two-site assay, we measured the concentration of the alpha 6/beta 4 integrin in matched biopsies from primary lung tumors and from normal lung. These studies confirmed that the complex was differentially expressed in non-small versus small cell lung cancers and that it was also detectable in lysates from normal lung at low levels. The highest levels of alpha 6/beta 4 were found in moderately differentiated squamous cell carcinomas. By immunohistochemistry, the beta 4 subunit was detectable in all the squamous cell carcinoma and adenocarcinomas tested (a total of 59), but not in 10 small cell cancers. The patterns of immunoreactivity were consistent with the expected distribution of membrane glycoproteins and, in some squamous cell carcinomas, were suggestive of the localization displayed by molecules involved in carcinoma-stroma interaction. Immunohistochemical staining indicated that beta 4 was also expressed in specific types of nonrespiratory pulmonary epithelial cells.

Adenocarcinoma↗
PubMed1989

Ligand-induced phosphorylation of a murine tumor surface protein (TSP-180) associated with metastatic phenotype.

A tumor surface protein (TSP-180) has been identified on murine lung carcinomas using two monoclonal antibodies (MoAbs) (135-13C and 346-11A). Quantitative analysis of TSP-180 on 3LL variants maintained either in vitro or in vivo indicates that TSP-180 is highly expressed in highly malignant metastatic cells. In reducing conditions, sodium dodecyl sulfate-polyacrylamide gel electrophoresis banding patterns of TSP-180 obtained with MoAb 135-13C from cell lysates of 3LL metastatic cells show three proteins migrating to Mr 204,000, 134,000, and 116,000. In the same experimental conditions MoAb 135-13C precipitates from low metastasizing ones only one band, corresponding to the lower molecular weight (Mr 116,000). All bands of TSP-180 observed in 3LL variants are labeled by lactoperoxidase-catalyzed radioiodination of viable cells, incorporate 32PO4, and contain carbohydrates, as judged by binding to wheat germ agglutinin. These results indicate that all proteins have external exposure on the cell surface and that at least some of TSP-180 proteins could be differentially regulated in different tumor cells (highly metastatic versus low metastatic). Sodium dodecyl sulfate-polyacrylamide gel electrophoresis banding patterns and immunoblots obtained from cell lysates of 3LL variants by using a monoclonal antibody to phosphotyrosine (IG-2) indicate that this MoAb recognizes proteins migrating with molecular weights identical to those reported for TSP-180. Moreover, the immunoblots of solubilized immunocomplex, obtained from cell lysates of 3LL variants by using MoAb 135-13C, demonstrate that MoAb IG-2 specifically reacts with TSP-180 proteins. Experiments undertaken in order to assess if some or all of TSP-180 proteins have tyrosine kinase activity demonstrate that MoAb 135-13C binding to the cell surface induces specific phosphorylation of the Mr 204,000 protein of TSP-180. Phosphoaminoacid analysis of the ligand-induced phosphorylated protein (pp204) demonstrates that this protein is phosphorylated at serine and tyrosine. Results reported lead us to hypothesize that TSP-180 is involved in growth-regulation mechanisms and that its high expression on cells with more malignant phenotype could be responsible for a proliferative advantage of such tumor clones.

Amino Acids↗
PubMed1989

Extremely low frequency pulsed electromagnetic fields increase cell proliferation in lymphocytes from young and aged subjects.

The effect of the in vitro exposure to extremely low frequency pulsed electromagnetic fields (PEMFs) on the proliferation of human lymphocytes from 24 young and 24 old subjects was studied. The exposure to PEMFs during a 3-days culture period or during the first 24 hours was able to increase phytohaemagglutinin-induced lymphocyte proliferation in both groups. Such effect was greater in lymphocytes from old people which showed a markedly reduced proliferative capability and, after PEMF exposure, reached values of 3H-TdR incorporation similar to those of young subjects. The relevance of these data for the understanding and the reversibility of the proliferative defects in cells from aged subjects and for the assessment of risk related to the environmental exposure to PEMFs has to be considered.

Adult↗
PubMed1989

Insulin-induced phosphorylation of the beta-4 integrin subunit expressed on murine metastatic carcinoma cells.

A tumor surface protein (TSP-180) that is highly expressed on highly malignant metastatic cells has been identified on murine lung carcinomas. On SDS-PAGE under reducing conditions, TSP-180 shows a complex banding pattern corresponding to 204, 183, 150, 135, and 116 kDa. All bands of the TSP-180 complex are glycosylated and are labeled by lactoperoxidase-catalyzed radioiodination of viable cells. The mouse TSP-180 complex described here is homologous to the human integrin alpha 6 beta 4 complex, and in particular it has been demonstrated that protein corresponding to 204 kDa is homologous to the beta 4 subunit of the integrin complex. It has been shown recently that monoclonal antibody to TSP-180 (MoAb 135-13C) stimulates cell growth in vitro and induces phosphorylation of the 204-kDa protein. We now report that insulin increases the phosphorylation of the 204-kDa protein 30-fold in intact carcinoma cells and epidermal growth factor (EGF) causes a threefold increase. Insulin-like growth factor (IGF-I) and platelet-derived growth factor have no effect. The effect of insulin and of IGF-I on phosphorylation of their own receptors was studied using solubilized cell membranes. Insulin and IGF-I each induced a fivefold increase in the phosphorylation of their respective receptor beta subunits. In order to test if phosphorylation of the 204-kDa protein was induced by direct binding of growth factors to TSP-180 and to identify growth factor receptors on line 1 cells, affinity cross-linking studies were performed. Affinity labeling of receptors demonstrated that insulin and IGF-I both bind to a 135-kDa protein that corresponds to the insulin and IGF-I receptor alpha subunits. Affinity labeling of EGF receptors failed to demonstrate EGF receptor molecules (175-kDa protein) on line 1 cells. Further investigations by using a different approach confirmed the very low amount of EGF receptors on line 1 cells. Direct phosphoamino acid analysis of the 204-kDa protein purified from insulin-stimulated cells demonstrated that this beta 4 integrin subunit is phosphorylated on serine and tyrosine. We conclude that beta 4 integrin molecule is a target for phosphorylation through an indirect receptor-mediated mechanism.

Amino Acids↗
PubMed1989

[Echo-guided renal biopsy in patients with a medical nephropathy].

Ninety-five percutaneous renal biopsies under ultrasound guidance were performed on 89 patients with nephrologic diseases. Accurate diagnosis was reached in 93% of cases at the first biopsy, and the figure increased to 100% after a second biopsy. The use of 18 and 16 gauge needles allowed correct histological diagnosis in 95% of patients, and satisfactory histology in the extant 5%. US guidance and the use of 18 and 16 gauge needles reduced the complications related to renal biopsy: in fact, severe hematuria occurred in 2 cases only.

Adolescent↗
PubMed1988

Recombinant human IFN-gamma, but not IFN-alpha or IFN-beta, enhances MHC- and non-MHC-encoded glycoproteins by a protein synthesis-dependent mechanism.

Despite quantitative as well as qualitative differences, all three types of IFN (IFN-alpha, IFN-beta, and IFN-gamma) modulate the synthesis as well as the expression of class I and class II histocompatibility Ag and a melanoma-associated Ag located in the plasma membrane as well as the cytoplasm of human melanoma cells. By employing inhibitors of RNA and protein synthesis it was demonstrated that IFN-alpha and -beta increase the expression of histocompatibility products and this tumor-associated Ag by a process not requiring new protein synthesis. In contrast, IFN-gamma does require de novo protein synthesis for its modulatory activity. Thus, it appears that IFN might trigger various adaptive functions in different cell lineages by inducing at least two separate sets of responses specific for either IFN-alpha and -beta or IFN-gamma. Because the induction requirements for (2'-5')-oligoadenylate synthetase as well as for the development of a cellular antiviral state by different IFN also display a similar protein synthesis dependence pattern, the present results suggest that a similar set of cellular mediators may be involved in the modulation of antigenic expression by IFN-gamma in human melanoma cells.

Antigens, Neoplasm↗
PubMed1988

Monoclonal antibody to human carcinoma-associated protein complex: quantitation in normal and tumor tissue.

We have identified and quantitated a tumor protein complex, TSP-180, on murine carcinomas with two monoclonal antibodies (MoAbs) (Cancer Res., 46: 707-712, 1986). One of the two MoAbs, 135-13C, recognizes a TSP-180-like protein complex on several human carcinomas in culture. MoAb 135-13C has been used to purify the human TSP-180 complex from A431 cells and the purified material used to immunize F344 rats to produce another MoAb, 439-9B, to the human TSP-180 complex. This MoAb does not precipitate the murine TSP-180 or bind to murine cells. Both MoAb 135-13C and 439-9B precipitated the same proteins from A431 cells but did not compete with each other for binding sites, indicating that they recognize different epitopes on the same protein. The two MoAbs have been used in a two-site assay to quantitate TSP-180 proteins on human cells and tissues. Carcinoma cell lines A431, SW948, and A549 all give high values (46 to 443 ng/mg of protein) while murine tumors, a human melanoma, and human fibroblasts are negative (less than 10 ng/mg of protein). Most tissues from autopsy of 2 normal individuals are negative for human TSP-180 at the levels tested (less than 10 ng/mg of protein). Some organs have intermediate range expression: spleen, 5 to 111 ng/ml of protein; colon, 24 to 111; and small intestine, 39 to 99. One primary colon and one larynx tumor were positive (144 to 372 ng/mg of protein) while 5 breast carcinomas, a stomach tumor, a metastatic melanoma, and a kidney tumor were negative. These data indicate that human TSP-180 may be preferentially expressed in certain malignant carcinomas of diverse origin. The potential for TSP-180 as a tumor marker requires further study.

Animals↗
PubMed1988

MHC antigens expressed on 3LL metastatic variants: correlation with the expression of a TSP-180 protein.

In attempts to correlate metastatic potential with specific properties of tumor cells, homogeneous subpopulations, which are endowed with low or high metastatic potential, have been selected from Lewis lung carcinoma (3LL). In particular, since cell surface constituents are possibly involved in the metastatic process, changes in antigen expression have been correlated with the metastatic potential of 3LL variants. In this view, we quantitated the expression of MHC (Db,Kb) antigens and of a tumor specific protein (TSP) identified by the monoclonal antibody (MoAb) 135-13C on some "in vitro" and "in vivo" variants of 3LL. The MoAb 135-13C was found to recognize a TSP-180 protein that appears on the cell surface of several murine carcinomas, but is not detected on normal cells in culture. Studies of the MHC expression on these variants, by the use of the indirect immunofluorescent staining or the direct binding of the MoAb to H-2Db (28-14-8) and the MoAb to H-2Kb (28-13-3), demonstrate that "in vivo" and "in vitro" 3LL variants which, are endowed with a higher metastatic potential, express on the cell surface a higher amount of the Db antigen. By contrast, all the 3LL lines have few cells recognized by the MoAb to H-2Kb and express low amounts of this antigen on the cell surface. The direct binding to different tumor lines and the analysis of the immunoprecipitates from the cell lysates by the use of the MoAb 135-13C demonstrate that the TSP-180 protein is highly expressed on 3LL cells which possess high capacity to metastasize to the lung. The variations induced in 3LL metastatic phenotype by the injection of the variant lines in allogeneic mice (Balb/c, C3HeB:H-2d,H-2k, respectively) or after treatment with the specific MoAb 135-13C have, also, been studied. An attempt was made to correlate the changes in 3LL metastatic phenotype with the expression of the TSP-180 protein and of the MHC antigens. We conclude that a high expression on the cell surface of the Db antigen and of the TSP-180 protein, is associated with a high malignant phenotype of 3LL tumor cells.

Animals↗
PubMed1987

Metastatic dissemination of 3LL variants after treatment with monoclonal antibody to a tumor-associated antigen.

Two tumor lines derived from 3LL (Lewis lung carcinoma) endowed with different metastatic potential and stable for their metastatic phenotype during serial in vivo passages, have been analysed for growth and dissemination following treatment with a monoclonal antibody. We have used a recently developed MoAb 135-13C to a tumor-associated antigen of murine lung carcinoma having an apparent molecular weight of 180,000 (TSP-180). The metastatic dissemination of the 3LL variants before and after treatment with the MoAb has been correlated with the expression on the cell surface of the MHC antigens (Db, Kb) and of the TSP-180 protein. The results of this study indicate that cell with high TSP-180 protein expression and MHC antigen expression have the greatest metastatic potential. Administration of MoAb 135-13C to tumor-bearing mice or i.v. injection of cells preincubated with the MoAb 135-13C increase the dissemination capacity of the variant endowed with lower metastatic potential while inducing a reverse effect on the high metastatic one. Studies on the MHC expression demonstrate that MoAb 135-13C treatment induces changes in the Db and Kb expression at level of secondary neoplasms. The results are discussed in view of the importance of the use of the metastatic variants to study therapeutic effect of specific targeting agent.

Animals↗
PubMed1986

Expression of tumor antigen correlated with metastatic potential of Lewis lung carcinoma and B16 melanoma clones in mice.

Expression of a tumor-associated antigen, recognized by a monoclonal antibody (MoAb 135-13C) to lung carcinoma cells, has been studied in cloned Lewis lung carcinoma (3LL) and in B16 melanoma (F1 and F10) tumor lines endowed with different metastatic potentials. MoAb 135-13C recognizes a protein complex (tumor-specific Mr 180,000 protein) that appears on the cell surface of several murine lung carcinomas but is not detected on normal cells in culture. Standard metastatic variants of B16 melanoma (F1 and F10) and two variant sublines of 3LL (M1087 and BM21548) together with the parental line of 3LL have been used for these experiments. The two cloned variant lines derived from 3LL have been shown to retain high (M1087) and low (BM21548) metastatic phenotypes during in vivo passaging. We found that all three cell lines of 3LL bind monoclonal antibody specifically, but one cell variant with higher metastatic potential shows a higher capacity to bind MoAb 135-13C than did the other variant. Similarly we found that B16 F10 cells bind higher amounts of MoAb 135-13C than did B16 F1 cells. In addition the analysis of the amounts of MoAb 135-13C bound to the cell surface of several other in vitro and in vivo tumor lines with different metastatic capacity demonstrates that all tumor lines which express high ability to colonize to the lung also express, on the cell surface, higher amounts of tumor-specific Mr 180,000 protein. The sodium dodecyl sulfate-polyacrylamide gel electrophoresis autoradiograms of immunoprecipitates from cell lysates of 3LL and B16 tumor lines demonstrate that MoAb 135-13C specifically precipitated three proteins banding at molecular weights of 204,000, 134,000, and 116,000. We conclude that MoAb 135-13C recognizes a surface protein complex which is present in higher amounts in 3LL and B16 cells which possess higher capacity to metastasize to the lung.

Animals↗
PubMed1985

Etoposide prior to cis-diamminedichloroplatinum in combination chemotherapy: in vitro and in vivo studies.

Antitumor effect and toxicity of etoposide (VP 16) in combination with cis-diamminedichloroplatinum (DDP) were studied on the in vitro C108 line and its in vivo counterpart, the M1087 line, both deriving from Lewis lung carcinoma. A colony-forming assay was used to assess the in vitro cytotoxicity of each drug and, on the basis of survival curve shape indications, different drug sequences were analyzed in order to find the optimal combination. Tumor growth inhibition, growth delay, metastasis reduction and percentage increase in lifespan were considered as parameters of therapeutic effect. From the present work it can be derived that the VP 16-DDP combination produces a poor antitumour effect against the Lewis lung carcinoma lines, otherwise associated with a highly acute toxicity. The sequence in which VP 16 is given before DDP induces a significant antimetastatic effect together with acceptable toxicity.

Animals↗
PubMed1985

Treatment with monoclonal antibody to a Lewis lung carcinoma-associated antigen: different effects on primary tumor and its metastases.

The growth and dissemination of Lewis lung carcinoma have been analyzed following treatment of isolated tumor cells or of tumor-bearing animals with monoclonal antibody (MoAb) 135-13C, which recognizes a cell surface tumor-associated protein of 180,000 daltons. The results of this study indicate that MoAb 135-13C binds with high affinity to Lewis lung tumor cells and induces different effects on the primary tumor (20%-25% reduction of tumor weight) and its metastasis (twofold increase of lung nodule formation). Different schedules of MoAb 135-13C administration have shown that these effects are dose- and time-dependent. In particular, the maximum increase in metastasis formation is observed when the MoAb 135-13C is administered at time of systemic tumor dissemination. In vitro preincubation of tumor cells with MoAb prior to their iv injection into normal animals results in a significant increase of pulmonary metastatic nodules.

Animals↗
PubMed1979

In vitro and in vivo selection of two Lewis lung carcinoma cell lines.

Two tumor cell lines adapted to grow in vitro were originated from an explant of lung metastases of Lewis lung carcinoma. These lines differ in their malignancy when reinoculated into syngeneic animals; nevertheless, they do not show any difference for their in vitro clonogenic ability. From these lines 2 in vivo sublines of 3LL carcinoma were developed. The TD50 of the 2 in vivo sublines are different, and both the values obtained are lower than that of the original line. These results are interpreted as a selection of more malignant tumor cell lines.

Animals↗