Biomedical subjects

R Ferracini

Publications and source records attributed to R Ferracini.

At least 19 recordsLinked to original sources

PubMed2004

Reversal of multidrug-resistance using Valspodar (PSC 833) and doxorubicin in osteosarcoma.

High-grade osteosarcoma is an extremely aggressive neoplasm, where over 80% of patients present with life-threatening micrometastases at diagnosis. Systemic control of the disease is therefore critical for the treatment of these patients and neoadjuvant chemotherapy using various drugs, including doxorubicin (DXR), which has been demonstrated to be the most effective regimen. Multidrug resistance (MDR) to some anticancer agents, including DXR, mediated by the MDR1 gene product P-glycoprotein (Pgp), has been shown to be a major cause of chemotherapy failure in osteosarcoma. We analyzed the effect of a cyclosporine A derivate Valspodar (PSC 833) on MDR human osteosarcoma cells. We also evaluated Pgp expression in sporadic appendicular canine osteosarcoma. Moreover, dogs were treated with combined administration of DXR and PSC 833. Several blood samples were collected for the determination of DXR and PSC 833 levels. PSC 833 induced a complete reversal of the resistant phenotype at concentrations compatible with the clinical use. Pgp was present in 12/18 (66.6%) of the cases. At the time of DXR administration, adequate blood concentrations of PSC 833, to provide a complete MDR reversal, were obtained without clinical or laboratory findings of toxicity. Combination therapy with DXR and PSC 833 allowed a 30% decrease in DXR dose infusion with equivalent therapeutic exposure. The high incidence of Pgp expression in osteosarcoma confers to the study a rationale for an effective regimen based on down-modulation of MDR.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

PubMed2002

Role of Paracoccidioides brasiliensis cell wall fraction containing beta-glucan in tumor necrosis factor-alpha production by human monocytes: correlation with fungicidal activity.

The polysaccharide fraction of Paracoccidioides brasiliensis mycelial cell wall (F1 fraction), the active component of which is composed of beta-glucan, was investigated in regard to the activation of human monocytes for fungal killing. The cells were primed with interferon-gamma (IFN-gamma) or F1 (100 and 200 microg ml(-1)) or F1 (100 and 200 microg ml(-1)) plus IFN-gamma for 24 h and then evaluated for H2O2 release. In other experiments, the cells were pretreated with the same stimuli, challenged with a virulent strain of P. brasiliensis and evaluated for fungicidal activity and levels of tumor necrosis factor (TNF-alpha) in the supernatants. F1 increased the levels of H2O2 in a similar manner to IFN-gamma. However, a synergistic effect between these two activators was not detected. On the contrary, a significant fungicidal activity was only obtained after priming with IFN-gamma plus F1. This higher activity was associated with high levels of TNF-alpha in the supernatants of the cocultures. Overall, P. brasiliensis F1 fraction induced human monocytes to release relatively high levels of TNF-alpha, which, in combination with IFN-gamma, is responsible for the activation of human monocytes for effective killing of P. brasiliensis.

Cell Culture Techniques↗

PubMed2001

Bone allografts and adjuvant cisplatin for the treatment of canine appendicular osteosarcoma in 18 dogs.

The results achieved in 18 dogs following the use of frozen bone cortical allografts for limb-sparing resection of non-metastatic canine appendicular osteosarcoma are presented. Three to five cisplatin doses (70 mg/m2) were administered, starting the day after surgery. The mean and median survival times were 478 and 266 days (range 80 to 2,611 days), respectively. The survival rate was 94 per cent at three months, 78 per cent at six months, 35 per cent at 12 months, 23 per cent at 18 months and 19 per cent at 24 months; the disease-free interval was 80 to 1,246 days (mean 365 days, median 266 days). Lung metastasis developed in 55 per cent of the dogs within one year. Complications were observed in 14/18 dogs (78 per cent), comprising local recurrence (28 per cent), allograft infection (39 per cent) and implant failure (11 per cent). Despite complications, limb sparing is a useful alternative to amputation in selected cases of appendicular osteosarcoma.

Animals↗

PubMed2001

Isolated hemangioblastoma of the filum terminale. Case report.

The filum terminale is an exceptional location for isolated hemangioblastoma. Only five cases are reported in literature, prior to the magnetic resonance imaging era. A 57-year-old man was referred to our Department with a prolonged history of progressive back pain, particularly severe when recumbent, and recurrent unilateral sciatalgia. Computed tomography demonstrated a non-homogeneous mass at L4 level. Magnetic resonance imaging displayed earliness and homogeneous enhancement of the mass with tortuous vessels above the rostral pole of the tumour, suggesting the diagnosis of a vascular tumour. The tumour was totally removed. Histological examination confirmed the hemangioblastoma diagnosis. The case indicates that hemangioblastoma, although uncommon, must be taken into consideration in cauda equina tumour diagnosis, and also emphasises the specificity of magnetic resonance features.

Cauda Equina↗

PubMed2000

The expression of Met/hepatocyte growth factor receptor gene in giant cell tumors of bone and other benign musculoskeletal tumors.

Overexpression of the hepatocyte growth factor receptor (Met/HGF receptor), a transmembrane tyrosine kinase encoded by the MET proto-oncogene, is involved in transformation and invasive behavior of human carcinomas and sarcomas. We have previously found that bone sarcomas express high levels of Met/HGF receptor while in some cases the ligand HGF is co-expressed with the receptor, activating an autocrine loop. In this study, we analyzed 40 biopsy samples of a collection of giant cell tumors and other rare benign tumors of bone for expression of the MET proto-oncogene. These included nonossifying fibromas, osteoblastomas, desmoplastic fibromas of bone, chondroblastomas, and giant cell tumors of bone. Snap frozen samples were tested for the MET and HGF gene expression by immuno-histochemistry and Western blotting with anti-MET antibodies and RT-PCR. Over 50% of all cases scored positive for MET expression being constantly positive in recurrent or locally aggressive lesions. Sporadic co-expression of the Met/HGF receptor and ligand is also demonstrated. Met/HGF receptor expression in benign bone neoplasms suggests its early involvement in sarcomagenesis.

Adult↗

PubMed2000

MET oncogene aberrant expression in canine osteosarcoma.

The objective of this study was to investigate the role of the MET oncogene in canine osteosarcoma. Seven large-breed dogs affected by spontaneous skeletal osteosarcoma underwent en bloc tumor excision. Total RNA was extracted from frozen tumor samples and assessed for expression of the MET oncogene by Northern blot analysis. Five of seven biopsy samples expressed high levels of the MET oncogene; its expression in the primary tumors was comparable with that previously identified in primary osteosarcomas in humans. A lung metastasis from one of the dogs expressed MET at a higher level than did its primary tumor. Spontaneously arising osteosarcoma in dogs clinically and pathologically mimics the corresponding disease in humans. We previously demonstrated that the MET oncogene was aberrantly expressed in a high percentage of human osteosarcomas. The results of the current study also provide a molecular parallel between the tumors in dogs and humans. This in vivo model may be helpful in evaluating new strategies for therapy against osteosarcoma.

Animals↗

PubMed1999

Assessment of vascularized fibular graft one year after reconstruction of the wrist after excision of a giant-cell tumour.

We report a patient in whom the distal radius was resected for a giant cell tumour and the bone defect was replaced using a vascularized proximal fibular graft. The graft was viable and hypertrophied and normal callus formed on the distal radius. Due to chronic instability of the wrist the patient underwent revision arthrodesis 1 year after resection. Microscopic studies of the epishyseal region of the fibula showed wide necrosis of the graft with active creeping substitution. Despite the good technical result of the vascularized fibular graft, the vascularization was incomplete in the proximal epiphysis. We discuss possible reasons for this.

Arthrodesis↗

PubMed1998

Distal ulnar tumours. Results of management by en bloc resection in nine patients and review of the literature.

A variety of reconstructive procedures have been suggested for stabilizing the ulnar shaft following resection of the distal ulna for tumour. We present the results of a series of nine distal ulnar tumour resections in which four different stabilization techniques were employed. We based our results on an evaluation of function, pain, motion, strength and instability. We obtained good or excellent results in seven patients treated with a soft tissue stabilization of the ulnar stump. One patient did not undergo any stabilization procedure and scored fair in our system. A further patient who required a radiocarpal arthrodesis also had an inferior result. These results suggest that soft tissue stabilization of the ulnar stump should be performed whenever possible.

Adult↗

PubMed1998

Capsular replacement with synthetic mesh: effectiveness in preventing postoperative dislocation after wide resection of proximal femoral tumors and prosthetic reconstruction.

We describe a surgical technique for replacing the hip joint capsule using synthetic mesh after oncological resections of the proximal femur that resulted in gross intraoperative instability of the prosthetic reconstruction. The results of its use in 13 patients, 6 of whom also had pelvic resections, are described. These patients were selected from a total group of 88 patients undergoing proximal femoral replacement, 75 of whom did not require capsular replacement (none of these 75 patients have experienced dislocation). In the group requiring capsular reconstruction, 1 of 4 patients with bipolar hemiarthroplasty and 4 of 9 patients with total hip replacements experienced dislocation after operation. Of the dislocated total hip replacements, 1 remains chronically dislocated, and 3 were successfully stabilized by open reduction with further capsular augmentation. Given that the resections involved removal of most of the soft tissues stabilizing the hip joint, we believe that the technique of capsular reconstruction is useful in this difficult group of patients.

Adult↗

PubMed1997

Cellular requirements for immunomodulatory effects caused by cell wall components of Paracoccidioides brasiliensis on antibody production.

In a previous study, we reported an increase in the number of immunoglobulin-secreting cells and the augmentation of antibody production (IgM and IgG3) against unrelated antigens (sheep erythrocytes or bovine serum albumin (BSA)) in mice infected with the fungus Paracoccidioides brasiliensis as well as in mice inoculated with its cell wall preparation (CW). The immunomodulatory effect of the live fungus and CW preparation was dose-dependent and mainly restricted to the i.p. inoculation simultaneously to the BSA challenge by the i.v. route. In the present study, we investigated the active component of CW preparation upon the phenotype and also the degree of activation of possible target peritoneal cells involved in those phenomena. An insoluble polysaccharide fraction (F1 fraction) mainly composed of beta-glucan and chitin, and the purified beta-glucan (BGPb) behaved as CW in the augmentation of early antibody production. The peritoneal mononuclear inflammatory cells induced by CW, F1 fraction and BGPb were highly positive to alpha-naphthyl esterase staining; released low H2O2; expressed high levels of MHC-Ia(d) molecules and produced inflammatory cytokines such as tumour necrosis factor-alpha (TNF-alpha) and IL-6. Phenotypic analysis by flow cytometry and immunohistochemical techniques of the inflammatory cells responding to F1 fraction showed a prevalence of (CD11b/CD18, Mac-1)+ peritoneal macrophages. In addition, s.c. inoculation of F1 fraction resulted in the formation of nodular, localized and not progressive granulomatous lesions with an accumulation of (CD11b/C18)+ macrophages. Adoptive transferred Mac-1 macrophages to immunized syngeneic recipient mice were able to cause an increase in anti-BSA antibody production. These results suggest that inflammatory (CD11b/CD18)+ macrophages may be related to immunological disturbances, caused by cell wall components of P. brasiliensis.

Adoptive Transfer↗

PubMed1997

[Primary malignant non-Hodgkin's lymphomas of the central nervous system in immunocompetent patients: diagnostic, prognostic and therapeutic criteria].

Primary central nervous system non-Hodgkin's malignant lymphomas (PCNSNHML) have undergone a remarkable increase in incidence in the last years. Clinically PCNSNHML may present with the symptoms that mimic many others neurological conditions. Radiologically they appear as iso or hyperdense deposits, often multiple, usually supratentorial in periventricular region. Histologically although most lesions are high grade B cell lymphomas, T cell lymphomas are being recognised with increasing frequency. Actually a substantial improvement in survival has been obtained using chemotherapy as sole treatment, eventually followed by radiotherapy for recurrences. The prognosis, however, remains poor in comparison with nodal lymphomas. It is improved by T-cell phenotype, a Karnofsky performance status more than 50%, age at onset less than 50 years and negativity for bcl-2 oncogene of neoplastic cells.

Adult↗

PubMed1996

Retrogenic expression of the MET proto-oncogene correlates with the invasive phenotype of human rhabdomyosarcomas.

The MET oncogene encodes the receptor for HGF/Scatter Factor, known to control cell motility and invasion in epithelial cells. We report that the Met/HGF receptor, absent in differentiated adult skeletal muscles, is aberrantly expressed in clinical samples and in established cell lines of human rhadbomyosarcomas. In both the embryonal and alveolar histotypes the oncogene is overexpressed and, in some cases, amplified. The Met receptor is exposed at the cell surface and is functionally active in response to HGF/Scatter Factor. Accordingly, rhabdomyosarcoma cells exhibit an invasive phenotype in vitro in response to exogenous HGF/Scatter factor. As the factor is known to be produced by connective tissues, a paracrine stimulation of rhabdomyosarcoma invasiveness in vivo is hypothesized. Two alveolar rhabdomyosarcomas were found in co-express the ¿two-kringle' alternatively-spliced HGF/Scatter Factor variant, which has been previously shown to stimulate cell motility and matrix invasion in vitro. These cells displayed the invasive phenotype in the absence of exogenous HGF/Scatter Factor, suggesting an autocrine mechanism in vivo. These data indicate that aberrant expression of the MET proto-oncogene provides rhabdomyosarcoma cells with the same property as embryonal myoblasts to migrate into the surrounding connective tissues.

Base Sequence↗

PubMed1996

Expression of Met/hepatocyte growth factor receptor gene and malignant behavior of musculoskeletal tumors.

Overexpression of the hepatocyte growth factor receptor (Met/HGF receptor), a transmembrane tyrosine kinase encoded by the met proto-oncogene, has been associated with tumor progression in different human carcinomas. More recently, the Met/HGF receptor has also been described in tumor cell lines of mesenchymal origin, suggesting the existence of an autocrine loop that may contribute to the pathogenesis of sarcomas. In this study, we analyzed the expression of Met/HGF receptor by Western blotting and immunohistochemistry in frozen samples of 87 primary tumors of bone and soft tissues. Among benign tumors, overexpression was consistently found only in giant-cell tumor, a locally aggressive lesion that may also, although rarely, spread to the lung. Among malignant lesions, the presence of the Met/HGF receptor was detected in a relevant percentage of primaries and in almost all of the recurrences. The highest levels of Met/HGF receptor were found in osteosarcoma, a highly aggressive tumor that typically permeates the host bone and rapidly expands to the soft tissues. On the contrary, only low levels of Met/HGF receptor were found in chondrosarcoma, a slowly growing tumor that usually expands without massive destruction of the surrounding structures. These data indicate an association of Met/HGF expression with local aggressiveness in human mesenchymal tumors. The finding of Met/HGF receptor overexpression in all of the osteosarcomas suggests a role for the met proto-oncogene in the pathogenesis of this tumor.

Adolescent↗

PubMed1995

The Met/HGF receptor is over-expressed in human osteosarcomas and is activated by either a paracrine or an autocrine circuit.

The c-MET oncogene encodes the receptor for the Hepatocyte Growth Factor/Scatter Factor (HGF), a cytokine that stimulates the invasive growth of normal and neoplastic cells. The Met/HGF receptor is expressed by epithelial cells and its ligand by cells of mesenchymal origin. Receptor-ligand interaction occurs via a paracrine circuit. We studied the expression of the Met/HGF receptor and of its ligand in mesenchymal human tumours by examining 39 clinical samples of bone tumours. The Met/HGF receptor was not detectable in the majority of bone tumours, as expected from their mesenchymal origin. Notably, the receptor was overexpressed in 60% of the osteosarcomas examined. In 12 osteosarcoma cell lines the Met/HGF receptor was overexpressed, phosphorylated by HGF stimulation and fully functional. HGF was detected in two out of seven clinical specimens of osteosarcoma. The ligand and the receptor are co-expressed in two clonal osteosarcoma cell lines. In these lines the Met/HGF receptor was constitutively phosphorylated; phosphorylation was suppressed by suramin treatment, a known blocker of autocrine loops. These data suggest that activation of the Met/HGF receptor by a paracrine or an autocrine mechanism might play a role in the particularly aggressive behaviour of osteosarcomas.

Bone Neoplasms↗

PubMed1995

Nuclear immunolocalization of P-glycoprotein in multidrug-resistant cell lines showing similar mechanisms of doxorubicin distribution.

The MDR1 gene product P-glycoprotein is a plasma membrane efflux pump which is responsible for multiple drug resistance of cancer cells. Although the ability of multidrug-resistant cells to exclude drugs from the nucleus is a distinctive and possibly the main mechanism for resistance against a number of drugs, including doxorubicin, this phenomenon is not entirely understood. In this paper, the relationship between doxorubicin subcellular distribution and P-glycoprotein activity at different cell sites has been investigated by different techniques. Cytofluorometry and confocal microscopy were used to study doxorubicin subcellular distribution in U-2 OS human osteosarcoma cells and in the multidrug-resistant variant U-2 OS/DX580. Stable levels of doxorubicin accumulation were found in the nuclei of sensitive cells, whereas the absence of detectable levels of drug in the nuclei of resistant cells could be attributed to an energy-dependent mechanism. Moreover, in resistant cells, inhibition of P-glycoprotein activity was able to induce drug accumulation in the nuclei of resistant cells and to achieve cytotoxic effects comparable to those observed in sensitive cells. Similar results were also found in isolated nuclei from U-2 OS/DX580 cells. The expression of P-glycoprotein in U-2 OS/DX580 and in two other multidrug-resistant cell lines (SW948-R-300 and LoVo-R-100) was investigated by confocal microscopy and immunoelectron microscopy, by using a panel of monoclonal antibodies directed against this protein. Higher levels of P-glycoprotein expression, not only in the plasma membrane and inside the cytoplasm, but also in the nucleus, were found in U-2 OS/DX580 and in LoVo-R-100 multidrug-resistant cells compared to their corresponding sensitive cells. SW948-R-300 cells, featuring increased amounts of MDR1 mRNA but lacking P-glycoprotein expression at the cell surface, showed a higher P-glycoprotein immunolabeling only in the nucleus and in the cytoplasm. The localization of P-glycoprotein in the nucleus of multidrug-resistant cells was confirmed also by studies on isolated nuclei and nuclear matrices, and by Western blot analysis on total cell and isolated nuclear extracts. These findings, suggesting the possible involvement of nuclear P-glycoprotein in the regulation of subcellular doxorubicin distribution in multidrug-resistant cells, open new insights on the mechanisms of P-glycoprotein-mediated resistance to anticancer drugs.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

PubMed1993

Non-Hodgkin lymphomas of the central nervous system. Clinico-pathologic and immunohistochemical study of 147 cases.

We report on data gathered from five European centres regarding 147 primary non-Hodgkin Lymphomas (NHLs) of the Central Nervous System (CNS) in HIV-negative patients. The results lead us to make the following considerations: i) there has been a significant and progressive increase in the frequency of observation of this pathology during the course of the last two decades; ii) the pathology lacks specific characteristic symptoms; iii) the radiological profile, as observed by CAT and/or MNR, most frequently corresponds to an isodense or slightly hyperdense lesion which has clear margins and is capable of assuming the contrast medium homogeneously; iv) the tumour most often has a single supratentorial localisation; v) high grade B-cell lymphomas account for 66% of the observations, low grade B-cell varieties being relatively rare and cases of T-cell derivation exceptional (6/147); vi) immunohistochemistry allows the differential diagnoses with respect to primitive or secondary non-lymphoid tumours, and provides confirmation of the histogenetic assessment made on morphological grounds; vii) the course of the disease is not significantly influenced by the histotype, the phenotype, the number of lesions present or the chemotherapy regimen, but rather by the employment of combined surgery and radio- or radiochemotherapy. This study represents the largest series of CNS NHLs so far reported, and as such, provides precise clinico-pathological indications which were only partially obtainable from the relatively small previously published series. Some concluding remarks are made as to the genesis of CNS NHLs, along with some practical suggestions for reaching a better understanding of their complex biology.

Adolescent↗

PubMed1993

Langerhans cells in Langerhans cell histiocytosis and peripheral adenocarcinomas of the lung.

The present paper deals with more precise characterization of Langerhans cells (LC) and accompanying lymphocytes in lung LC histiocytosis (LCH) and primary lung peripheral adenocarcinomas using immunohistochemical methods with various kinds of monoclonal antibodies against cell adhesion and activation markers and some cytokines. Tissue specimens were obtained from 4 patients with pulmonary LCH and from 29 patients with primary lung peripheral adenocarcinoma. In florid (exudative and granulomatous) nonfibrotic LCH lesions, LC, particularly those in contact with lymphocytes, were S100, CD1a, MHC Class II, CD11a and c, CD16, and CD54 positive. In this context, LC were CD4+ and CD25+. Lymphocytes around LC were CD3+ with a "memory" phenotype (CD45RO+) and, frequently, CD25+ and HLA-DR+. S100+ and CD1a+ LC were commonly observed in adenocarcinomas subclassified as papillary and as nonmucinous bronchioloalveolar, in both cases mainly where Clara cells and Type II pneumocytes were present. In carcinomas the vast majority of LC were HLA-DR+ and, rarely, weakly CD16+, CD25+, and CD54+. The infiltration of reactive cells in cancer tissue was mainly represented by T lymphocytes (CD3+CD45RO+). These T cells were HLA-DR- and CD25-. The presence of LC was associated with a strong reactivity of epithelial cells with antibodies PE-10 and 439-9B, both recognizing molecules mainly expressed by Type II alveolar cells. Several cells in LCH florid lesions showed immunoreactivity for both IL-1 alpha and beta. Immunostaining for IFN-gamma revealed the presence in the same areas of some positive cells showing lymphoid morphology. No IL-1 or IFN-gamma reactivity was found in adenocarcinomas.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenocarcinoma↗

PubMed1992

Meningeal sarcoma with rhabdomyoblastic differentiation: case report.

A case of primary neoplasm of the meninges with unusual histological and clinical features, which occurred in a 61-year-old man is described. Although conventional light microscopy revealed an undifferentiated tumor consisting of small- to medium-sized elements, it did not allow any definitive histogenetic interpretation. Immunohistochemistry showed that the neoplastic cells were positive for actin, desmin, myoglobin, and vimentin, thus leading to the diagnosis of meningeal sarcoma with rhabdomyoblastic differentiation. This interpretation was also supported by electron microscopy, in dewaxed tissue samples, which revealed the presence of abortive Z-lines. It is noteworthy that retrospective microscopic examination of all the slides obtained both at initial presentation and at relapses demonstrated in some fields that the undifferentiated population was associated with typical meningiomatous features, as was also shown by the staining for the epithelial membrane antigen. Clinically, the tumor was characterized by an exceedingly long course (10 years). The histogenesis of the tumor and the diagnostic relevance of immunohistochemical techniques are discussed.

Cell Transformation, Neoplastic↗