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Biomedical subjects

G Forni

Publications and source records attributed to G Forni.

At least 55 records · Page 3Linked to original sources
PubMed1999

Interleukin-2 gene transfer into human transitional cell carcinoma of the urinary bladder.

Transitional cell carcinoma of the bladder is one of the human cancers most responsive to immunotherapy, and local interleukin-2 (IL-2) production appears to be an important requirement for immunotherapy to be effective. In this study, we engineered two human bladder cancer cell lines (RT112 and EJ) to constitutively release human IL-2 by retroviral vector-mediated gene transfer. Following infection and selection, stable and consistent production of biologically active IL-2 was demonstrated at both the mRNA and the protein level. Morphology, in vitro growth rate and proliferation, as well as other cytokine gene mRNA or membrane adhesion receptor expression, were not altered in IL-2 transduced cells as compared to their parental or control vector-infected counterparts. Moreover, IL-2 engineered cells lost their tumorigenicity into nu/nu mice and the mechanism of rejection appeared to involve multiple host effector cell populations, among which a prominent role was played by neutrophils and radiosensitive cells. These findings may offer support to the development of an IL-2-based gene therapy approach to human bladder cancer.

Animals↗
PubMed1999

Analysis of mammary carcinoma onset and progression in HER-2/neu oncogene transgenic mice reveals a lobular origin.

Morphologic examinations of mammary neoplasias arising in BALB/c (H-2d) mice carrying the activated rat HER-2/neu oncogene (BALB-NeuT), and in FVB (H-2q) mice bearing the wild-type proto-oncogene (FVB-NeuN), indicate that both conditions result in a very human-like lobular carcinoma of alveolar type, whose histotype is the result of the preferential expression of HER-2/neu products in the epithelium of lobular ducts and lobules. Detailed analysis of tumor progression indicates that transition from lobular hyperplasia to overt carcinoma is associated with a high epithelial proliferation rate, as assessed by anti-proliferating cell nuclear antigen immunostaining, and coincides with the activation and maximal extension of tumor angiogenic process as assessed by microvessel count (anti-CD31), anti-beta3 integrin, and anti-laminin immunostaining. Neovascularization is accompanied by vascular endothelial cell growth factor and basic fibroblast growth factor production by hyperplastic epithelial cells. By contrast with the BALB-NeuT tumors, E-cadherin expression is almost nonexistent in those arising in FVB-NeuN mice and this may explain their high metastatic potential. Despite their different kinetics, however, the lung metastases observed in both strains are histologically similar and resemble the primary tumor. Both strains can thus be proposed as models for "in vivo" investigation of the origin and progression of the alveolar type of lobular mammary carcinoma and the testing of new therapeutic approaches.

Animals↗
PubMed1999

Cytokine gene-engineered vaccines.

Cytokines modulate immune reactivity and have therefore been used to build cancer vaccines. Experimental vaccination of rodents and humans with cytokine-gene engineered tumor cells, fusion proteins between cytokines and tumor antigens, and their DNA have been shown to induce a significant immune memory, even against poorly immunogenic tumors. This immune memory can prevent tumor growth and cure initial metastases, but is poorly effective against established tumors. To date clinical trials have been confined to patients with advanced tumors; so far they suggest that this approach is safe.

Adjuvants, Immunologic↗
PubMed1998

Beta-galactoside-binding protein (beta GBP) alters the cell cycle, up-regulates expression of the alpha- and beta-chains of the IFN-gamma receptor, and triggers IFN-gamma-mediated apoptosis of activated human T lymphocytes.

In this paper, the effects of beta-galactoside binding protein (beta GBP), the LGALS1 gene product, on the cell cycle progression and expansion of activated human T lymphocytes were studied. Beta GBP drastically inhibits the IL-2 induced proliferation of PHA-activated T lymphocytes as well as the IL-2 independent proliferation of malignant T lymphocytes by arresting them in the S and G2/M phases of the cell cycle. In addition, beta GBP up-regulates the expression of both the alpha- and the beta-chains of the IFN-gamma R on activated T lymphocyte membrane. None of these effects depend on sugar binding: saturating amounts of lactose do not affect the cell cycle block nor IFN-gamma R up-modulation. The increased expression of both chains renders beta GBP-treated T lymphoblasts sensitive to IFN-y-induced apoptosis. Taken as a whole, these findings suggest that beta GBP plays an important immunoregulatory role by switching off T lymphocyte effector functions. They also provide the first evidence of up-modulation of IFN-gamma R expression on T lymphocytes by a negative cell growth regulator.

Apoptosis↗
PubMed1998

Interleukin 12-mediated prevention of spontaneous mammary adenocarcinomas in two lines of Her-2/neu transgenic mice.

The ability of interleukin (IL)-12 to prevent tumors when administered to individuals with a genetic risk of cancer was studied in two lines of transgenic mice expressing rat HER-2/neu oncogene in the mammary gland. Female BALB/c (H-2(d)) mice carrying the activated HER-2/ neu oncogene show no morphological abnormalities of the mammary gland until 3 wk of age. They then progress through atypical hyperplasia to in situ lobular carcinoma and at 33 wk of age all 10 mammary glands display invasive carcinomas. Adult FVB mice (H-2(q)) carrying the HER-2/neu protooncogene develop mammary carcinomas with a longer latency (38-49 wk) and a lower multiplicity (mean of 2.6 tumors/mice). Treatment with IL-12 (5 daily intraperitoneal injections, 1 wk on, 3 wk off; the first course with 50 ng IL-12/day, the second with 100 ng IL-12/day) begun at 2 wk of age in BALB/c mice and at 21 wk of age in FVB mice markedly delayed tumor onset and reduced tumor multiplicity. Analogous results were obtained in immunocompetent and permanently CD8(+) T lymphocyte-depleted mice. In both transgenic lines, tumor inhibition was associated with mammary infiltration of reactive cells, production of cytokines and inducible nitric oxide synthase, and reduction in microvessel number, in combination with a high degree of hemorrhagic necrosis.

Animals↗
PubMed1998

Peak exercise oxygen consumption in chronic heart failure: toward efficient use in the individual patient.

OBJECTIVES: This study sought to 1) assess the short-, medium-and long-term prognostic power of peak oxygen consumption (VO2) in patients with heart failure; 2) verify the consistency of a nonmeasurable anaerobic threshold (AT) as a criterion of nonapplicability of peak VO2; 3) develop simple rules for the efficient use of peak VO2 in individualized prognostic stratification and clinical decision making. BACKGROUND: Peak VO2, when AT is identified, is among the indicators for heart transplant eligibility. However, in clinical practice the application of defined peak VO2 cutoff values to all patients could be inappropriate and misleading. METHODS: Six hundred fifty-three patients consecutively considered for eligibility for heart transplantation were followed up. Outcomes (cardiac death and urgent transplantation) were determined when all survivors had a minimum of 6 months of follow-up. RESULTS: Contraindication to the exercise test identified very high risk patients. The relatively small sample of women did not allow inferences to be drawn. In men, peak VO2 stratified into three levels (< or = 10, 10 to 18 and >18 ml/kg per min) identified groups at high, medium and low risk, respectively. The prognostic power of peak VO2 < or = 10 ml/kg per min was maintained even when the AT was not detected. In patients in New York Heart Association functional class III or IV, peak VO2 did not have prognostic power. In patients in functional class I or II, peak VO2 stratification was prognostically valuable, but less so at 6 than at 12 or 24 months. Age did not influence peak VO2 prognostic stratification. CONCLUSIONS: A contraindication to exercise testing should be considered a priority for listing patients for heart transplantation. Only in less symptomatic male patients does a peak VO2 < or = 10 ml/kg per min identify short-, medium- and long-term high risk groups. A peak VO2 >18 ml/kg per min implies good prognosis with medical therapy.

Anaerobic Threshold↗
PubMed1998

The immune response elicited by mammary adenocarcinoma cells transduced with interferon-gamma and cytosine deaminase genes cures lung metastases by parental cells.

The parental cells of the TSA murine mammary adenocarcinoma (TSA-pc) were transfected with both the interferon-gamma (IFN-y) gene and the cytosine deaminase (CD) suicide gene to obtain a therapeutic vaccine active against TSA-pc lung metastases. Even in the absence of treatment with the prodrug 5-fluorocytosine (5-FC), the local growth of double transfectants (CD-y clones) was inhibited by a marked recruitment of granulocytes and macrophages. In mice harboring TSA-pc micrometastases, therapeutic vaccination with either IFN-gamma or CD single transfectants reduced the number of lung nodules, whereas CD-gamma double transfectants abrogated metastasis growth in up to 80% of mice. Treatment of mice with 5-FC did not alter the curative efficacy of CD-gamma double-transfectant cells. By contrast, in mice vaccinated with CD single-transfectant cells, 5-FC treatment caused a significant loss of their curative activity. Host T cells played an active role in the cure of lung metastases, because vaccination of nude mice with CD-gamma cells was uneffective.

Adenocarcinoma↗
PubMed1998

Interaction between endothelial cells and the secreted cytokine drives the fate of an IL4- or an IL5-transduced tumour.

Injection of interleukin-4 (IL4) gene-transduced tumour cells into syngeneic immunocompetent mice resulted in tumour rejection in which a key role for eosinophils was suggested. To evaluate whether IL5 inhibits tumour growth by selectively inducing eosinophil recruitment and activation, a poorly differentiated mammary adenocarcinoma cell line (TSA) was transfected with the IL5 gene and the cells secreting IL5 (TSA-IL5) were injected subcutaneously (s.c.) in syngeneic mice. The oncogenicity of TSA-IL5 was compared with that exhibited by TSA cells transfected with the IL4 gene (TSA-IL4) and with the neomycin resistance gene only (TSA-neo). At progressive times after subcutaneous challenge, tumour growth areas were studied histologically, ultrastructurally, and immunohistochemically to identify the reactive cells, visualize tumour vessels, and detect the cytokines and chemokines involved in the anti-tumour reaction. Both the morphological and the functional data showed that TSA-IL5, despite the large eosinophil infiltrate, grew progressively like TSA-neo, suggesting that eosinophils per se do not play a crucial role in TSA tumour rejection. Furthermore, our data indicate that the rejection of TSA-IL4 depends on the IL4-induced expression of VCAM-1 and MCP-1 by endothelial cells. MCP-1 together with VCAM-1 results in recruitment and activation of basophils, mast cells, and macrophages, and hence a pro-inflammatory cytokine cascade that initially favours the influx and activation of neutrophils and finally tumour rejection. In this context, the rejection of TSA-IL4 seems to involve a variety of reactive cells and rests on a continuous cross-talk between basophils, mast cells, macrophages, CD8-positive lymphocytes, and granulocyte subsets, mostly neutrophils.

Animals↗
PubMed1998

Local release of interleukin-10 by transfected mouse adenocarcinoma cells exhibits pro- and anti-inflammatory activity and results in a delayed tumor rejection.

Tumor cells engineered to release cytokines are a valuable tool for investigating biological activities elicited by local cytokines. The parental cells of a mouse mammary adenocarcinoma (TSA-pc) were transduced with the cDNA coding for mouse interleukin-10 (IL-10). In vitro, transduced TSA cells secrete about 200 ng of IL-10/10(5) seeded cells in 48 hours (TSA-IL-10). When injected subcutaneously into syngeneic BALB/c mice, TSA-IL-10 cells gave rise to a tumor that grew progressively during the first 7-10 days and then rapidly and completely regressed. To study the events associated with this growth and disappearance, histological, immunohistochemical and ultrastructural analyses of the tumor area were performed at progressive times after challenge. A slow, but progressive and massive recruitment of leukocytes (mainly macrophages and neutrophils) into the tumor was evident. Several CD8+, CD4+ lymphocytes and a few NK cells were present. Marked inhibition of neoangiogenesis was also observed. On day 9, the microvascular network in the growth area had almost vanished, while vascular damage was present in the surrounding stromal tissue. From day 4, down-modulation of VEGF expression in the tumor area and inhibition of tumor necrosis factor-alpha (TNF-alpha) and IL-6 production by reactive leukocytes were evident. The few vessels present in the tumor area displayed poor expression of monocyte chemotactic protein-1 (MCP-1), moderate expression of VCAM-1, and strong expression of ELAM-1, three molecules that result in adhesion of inflammatory cells to the endothelium. A few tumor-infiltrating macrophages were moderately stained with anti-iNOS antibodies. These findings suggest that the collapse of established TSA-IL-10 tumors is the result of the pro- and anti-inflammatory activity of IL-10, which: a) is a signal for the local recruitment of leukocytes; b) leads to vascular damage; c) suppresses cytokine production. The coexistence of both a direct stimulatory activity on endothelial cells and an anti-angiogenic activity is evidence of the ambivalence of the local effects of IL-10.

Adenocarcinoma↗
PubMed1998

The bicaval anastomosis technique for orthotopic heart transplantation yields better atrial function than the standard technique: an echocardiographic automatic boundary detection study.

BACKGROUND: Atrial function is an important determinant of cardiac performance. In patients who undergo operation by standard heart transplantation atrial enlargement, distortion of geometry and asynchronous contraction resulting from the donor/recipient atrial connections may affect atrial function. The bicaval anastomosis technique should be free from these limitations. METHODS: We used the echocardiographic automatic boundary detection technique to obtain on-line time/volume curves of right and left atria from patients who had undergone bicaval (n = 22) or standard (n = 27) heart transplantation and from 15 control subjects. Maximal, middiastolic, preatrial contraction, and minimal volumes of both atria were measured. Reservoir volume (defined as the difference between maximal and middiastolic atrial volumes); pump volume (defined as the difference between preatrial contraction and minimal atrial volumes); and conduit volume (defined as the difference between left ventricular stroke volume and the sum of reservoir and pump volumes) were derived for both atria. Atrial emptying fraction was calculated as the difference between maximal and minimal volumes divided by the maximal volume and expressed in percent and pump fraction as the pump volume divided by the sum of reservoir and pump volumes. Tricuspid and mitral regurgitation, evaluated by color-flow Doppler scanning, were considered significant when they were greater than grade 1. Atrial ejection force was calculated from mitral and tricuspid flow velocities at atrial contraction. RESULTS: In patients who had bicaval heart transplantation, both atria were smaller than in patients who underwent standard heart transplantation. With the bicaval technique right and left atrial emptying (right 45% +/- 9% vs 36% +/- 10%, p < .05; left 51% +/- 8% vs 39% +/- 8%, p < .001) and pump fractions (right 57% +/- 17% vs 19% +/- 13%, p < .001; left 45% +/- 28% vs 22% +/- 12%, p < .01) were greater than with the standard technique and similar to those in control subjects. Right atrial ejection force was significantly greater in bicaval (10.0 +/- 5.6 kdyne) than in standard heart transplantation (4.5 +/- 2.2 kdyne, p < .0001). Significant tricuspid or mitral regurgitation was rarely found in bicaval heart transplant recipients (3 and 1 of the 22 patients, respectively), although they were much more frequent after standard heart transplantation (13 and 8 of the 27 patients, respectively). CONCLUSIONS: Heart transplantation performed with the bicaval anastomosis technique determines smaller atrial volumes, yields better right and left atrial function and fewer atrioventricular valve regurgitation than the standard technique.

Anastomosis, Surgical↗
PubMed1997

Antitumor efficacy of adenocarcinoma cells engineered to produce interleukin 12 (IL-12) or other cytokines compared with exogenous IL-12.

BACKGROUND: Numerous animal model studies have examined the ability of genetically engineered tumor cells to release cytokines and to elicit an immune memory against the parental tumor. Often only a single cytokine is studied, and few comparative studies have been conducted. PURPOSE: We evaluated the antitumor efficacy of adenocarcinoma cells engineered to release interleukin (IL)-12 in a mouse model system. The efficacy of this cytokine was compared with that of other cytokines released by engineered adenocarcinoma cells and that of exogenous IL-12 administered both locally and intraperitoneally. METHODS: BALB/cAnCr mice were inoculated with syngeneic parental mammary adenocarcinoma (TSA) cells in quantities sufficient to lead to tumors in all inoculated mice. TSA cells engineered to release IL-12 (TSA-IL12) were also injected into normal and selectively immunosuppressed BALB/cAnCr mice. Tumor incidence, growth, and rejection patterns were evaluated by the measurement of neoplastic masses and by the study of the histologic and ultrastructural features of the tumor site. The effects of local or intraperitoneal administration of recombinant IL-12 (rIL-12) on tumor-bearing animals were also studied. RESULTS: Most mice rejected TSA-IL12 cells through a CD8-positive, T-lymphocyte-dependent reaction associated with macrophage infiltration, vessel damage, and necrosis. The systemic immunity of mice that had rejected TSA-IL12 cells to a subsequent challenge with parental TSA cells was less efficient than that elicited by TSA cells engineered to release IL-4 or IL-10 but equivalent to that elicited by TSA cells engineered to release IL-2, IL-7, and interferon alfa. Compared with TSA cells engineered to produce other cytokines, TSA-IL12 cells were the most efficient in curing mice with established TSA tumors; injection of 0.1 million proliferating cells contralaterally to the tumor growth area cured five of 15 mice bearing 1-day-old tumors; injection of the same dose of proliferating cells into the tumor growth area cured two of 20 tumor-bearing mice. However, two 5-day courses with a nontoxic dose (0.1 microgram) of rIL-12 given intraperitoneally cured a similar proportion of these animals (six of 20). Only two of 20 mice with 7-day-old TSA tumors were cured by vaccination with proliferating TSA-IL12 cells, whereas 24 of 30 mice with such tumors were cured by intraperitoneal administration of rIL-12. CONCLUSIONS: TSA cells engineered to release IL-12 are rejected by most mice; the ensuing immune memory for TSA parental cells, however, was less efficient than that elicited by proliferating TSA cells engineered to release other cytokines (e.g., IL-4, IL-10, and possibly interferon gamma). The immune reaction elicited by TSA-IL12 cells was the most efficient in curing mice with established TSA tumors; notably though, the same or a better cure rate was obtained with rIL-12 given intraperitoneally.

Adenocarcinoma↗
PubMed1997

Expression and role in apoptosis of the alpha- and beta-chains of the IFN-gamma receptor on human Th1 and Th2 clones.

The mRNA and protein expression of the alpha- and beta-chains of IFN-gammaR were evaluated on a panel of human Th1 and Th2 clones. When cultured in IL-2-conditioned medium, both types of clones expressed mRNA for the alpha- and beta-chains, and both chains were present in the cytoplasm. Membrane expression of the alpha-chain was higher on Th2 than on Th1, whereas the beta-chain was poorly expressed on both types but increased following IL-2 withdrawal or PHA stimulation. In addition, both types of clones overexpressed MHC class I glycoproteins following IFN-gammaR triggering by exogenous IFN-gamma, although the kinetics was slower in Th1, and this exposure induced mRNA for IRF-1. When their TCR was triggered in the absence of APC, Th1 only underwent apoptosis. This activation-induced apoptosis was prevented by blocking of the alpha-chain or by IFN-gamma neutralization. Addition of IFN-gamma triggered the apoptosis of Th2 clones. Apoptosis of both types of clones was mediated by autocrine or exogenous IFN-gamma through the up-regulation of Fas-L expression, since anti-IFN-gammaR alpha mAb inhibited its expression on Th1 and exogenous IFN-gamma increased its expression on Th2. These results indicate that activated human Th1 and Th2 lymphocytes express IFN-gammaR alpha- and beta-chains and are both sensitive to signals provided by IFN-gamma. Data also suggest that IFN-gamma is critical for switching off their responses.

Apoptosis↗
PubMed1997

Extracellular matrix remodelling in a murine mammary adenocarcinoma transfected with the interferon-alpha 1 gene.

The rejection of interferon alpha 1 gene-transfected mammary adenocarcinoma cells (TSA-IFN alpha) injected into syngeneic BALB/c mice was accompanied by an unusual stromal reaction and marked CD8-positive T-lymphocyte involvement. To investigate the biological background of this reaction, the possibility was evaluated that an interaction between TSA-IFN alpha and stromal cells might remodel the extracellular matrix (EM). When fibroblasts were co-cultured with TSA-IFN alpha or treated with exogenous IFN alpha, there was no change in their replication rate or collagen synthesis. By contrast, their fibronectin (FN) production and release were increased, resulting in enhanced fibroblast chemotaxis. These findings were mirrored by increased FN staining in the peritumoural and tumoural areas in vivo. IFN alpha thus determines increased FN production and hence massive local recruitment and activation of fibroblasts, with a modification of the EM. The several activities of IFN alpha should thus be considered prior to its employment in clinical trials.

Adenocarcinoma↗
PubMed1997

Antiblastic chemotherapy drugs up-modulate interferon-gamma receptor expression on human malignant T cells.

We have previously shown that the contrasting ability of interferon-gamma (IFN-gamma) either to stimulate the proliferation of malignant T cells or to induce their apoptosis is determined by the low and high intensity of IFN-gamma receptor (IFN-gamma R) expression, respectively. High IFN-gamma R expression is a marker for the T cell stress that precedes apoptosis. In this paper, we show that a 12- to 24-h culture of three human malignant T-cell lines displaying distinct differentiation stages (ST4, PF382, and Jurkat) in medium supplemented with four chemotherapy drugs (etoposide, cisplatin, cytarabine, and daunomycin) up-modulates their IFN-gamma R expression followed by their apoptosis after 24-48 h later. Increased IFN-gamma R expression (by at least an order of magnitude) was observed in 30 to 90% of cells during exposure to pharmacologic drug concentrations. Timely combination of chemotherapy drugs with IFN-gamma may thus provide a more effective way of inhibiting the progress of human malignant T cells through synergistic induction of their apoptosis.

Antineoplastic Agents↗
PubMed1996

Assessment of right ventricular function in patients with congestive heart failure by echocardiographic automated boundary detection.

In patients with chronic heart failure, echocardiographic automated boundary detection (ABD) can reliably assess right ventricular function. The measurements obtained by ABD were highly reproducible, strongly correlated with radionuclide right ventricular ejection fraction, and superior to those obtained by conventional manual echocardiographic methods.

Electrocardiography↗
PubMed1996

Switching on of the proliferation or apoptosis of activated human T lymphocytes by IFN-gamma is correlated with the differential expression of the alpha- and beta-chains of its receptor.

To find out how physiologically secreted IFN-gamma controls either the proliferation or the apoptosis of human T lymphocytes, the kinetics of expression of the alpha- and beta-chains of its receptor (IFN-gamma R) were sequentially followed on T lymphocytes first activated with PHA and then cultured in the presence of IL-2, and related to the kinetics of expression of Fas, Bcl-2, and IL-2R p55 chain. Both IFN-gamma R chains were poorly expressed on the membrane of resting T lymphocytes. Following their stimulation with PHA, IFN-gamma R alpha but not IFN gamma R beta-chain up-modulated before T lymphocyte entry into the S phase, and then IFN-gamma R alpha down-modulated when they passed through the S and G2/M. The ensuing proliferative response was inhibited by an anti-IFN-gamma R alpha mAb that impeded the binding of IFN-gamma. When PHA-activated T lymphoblasts were cultured for 16 days with IL-2, IFN-gamma R alpha expression increased, whereas that of the beta-chain remained barely detectable. Fas and Bcl-2 were both highly expressed. When these T lymphoblasts were restimulated by PHA, OKT3, or Staphylococcus enterotoxin beta-pokeweed mitogen, both chains up-modulated and most cells underwent apoptosis in a way apparently independent of Bcl-2, but not of Fas. This apoptosis, too, was prevented by the anti-IFN-gamma R alpha mAb. Physiologically secreted IFN-gamma is thus involved in the activation of resting T lymphocytes and in the apoptosis of reactivated lymphoblasts. However, high expression of IFN-gamma R beta took place when IFN-gamma induced apoptosis, but not when it induced proliferation. In conclusion, a correlation exists between differential expression of the IFN-gamma R beta-chain and the delivery by IFN-gamma of proliferative or apoptotic signals.

Antibodies, Monoclonal↗