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Biomedical subjects

G Torelli

Publications and source records attributed to G Torelli.

At least 37 records · Page 2Linked to original sources
PubMed2001

Angiogenesis in multiple myeloma: correlation between in vitro endothelial colonies growth (CFU-En) and clinical-biological features.

Mouse models and studies performed on fixed bone marrow (BM) specimens obtained from patients with multiple myeloma (MM) suggest that plasma cell growth is dependent on endothelial cell (EC) proliferation within the BM microenvironment. In order to assess whether EC overgrowth in MM reflects a spontaneous in vitro angiogenesis, BM mononucleated cells from 13 untreated (UT) MM, 20 treated (11 with melphalan and nine with DAV schedule) MM, eight patients with monoclonal gammopathy of uncertain significance (MGUS) and eight controls were seeded in an unselective medium to assess EC proliferation. Furthermore, the influence of IL6 on the EC growth was investigated. Endothelial colonies (CFU-En) appeared as small clusters, formed by at least 100 slightly elongated and sometimes bi-nucleated cells expressing factor VIII, CD31 and CD105 (endoglin). The CFU-En mean number/10(6) BM mononucleated cells in untreated MM samples (2.07 s.d. +/- 1.3) was significantly higher than in normal BM (0.28 +/- 0.48), while no difference was seen between normal BM and MGUS (0.28 +/- 0.54). Interestingly, the mean number of CFU-En in the DAV group (1.88 +/- 1.6) did not differ from the UT, while it was found to be lower in the melphalan group (0.31 +/- 0.63). The addition of anti-IL6 monoclonal antibody induced a reduction of both the plasma cells in the supernatant and the CFU-En number. This study describes a rapid and feasible assay providing support for the association between EC and plasma cells further suggesting that the in vitro angiogenesis process may parallel that observed in vivo.

Adult↗
PubMed2001

The prognostic value of cytogenetics is reinforced by the kind of induction/consolidation therapy in influencing the outcome of acute myeloid leukemia--analysis of 848 patients.

We studied the impact of cytogenetics and kind of induction/consolidation therapy on 848 adult acute myeloid leukemia (AML) patients (age 15-83). The patients received three types of induction/consolidation regimen: standard (daunorubicin and cytosine arabinoside (3/7); two cycles); intensive (idarubicin, cytosine arabinoside and etoposide (ICE), plus mitoxantrone and intermediate-dose Ara-C (NOVIA)); and low-dose (low-dose cytosine arabinoside). CR patients under 60 years of age, if an HLA-identical donor was available received allogeneic stem cell transplantation (allo-SCT); otherwise, as part of the program, they underwent autologous (auto)-SCT. CR rates significantly associated with 'favorable' (inv(16), t(8;21)), 'intermediate' ('no abnormality', abn(11q23), +8, del(7q)) and 'unfavorable' (del (5q), -7, abn(3)(q21q26), t(6;9), 'complex' (more than three unrelated cytogenetic abnormalities)) karyotypes (88% vs 65% vs 36%, respectively; P = 0.0001). These trends were confirmed in all age groups. On therapeutic grounds, intensive induction did not determine significant increases of CR rates in any of the considered groups, with respect to standard induction. Low-dose induction was associated with significantly lower CR rates. Considering disease-free survival (DFS), multivariate analysis of the factors examined (including karyotype grouping) showed that only age > 60 years significantly affected outcome. However, in cases where intensive induction was adopted, 'favorable' karyotype was significantly related to longer DFS (P = 0.04). This was mainly due to the favorable outcome of t(8;21) patients treated with intensive induction. Patients receiving allo-SCT had significantly longer DFS (P = 0.005); in particular, allo-SCT significantly improved DFS in the 'favorable' and 'intermediate' groups (P = 0.04 and P = 0.048, respectively). In conclusion our study could provide some guidelines for AML therapy: (1) patients in the 'favorable' karyotype group seem to have a longer DFS when treated with an intensive induction/consolidation regimen, adopted before auto-SCT instead of standard induction; this underlines the importance of reinforcement of chemotherapy, not necessarily based on repeated high-dose AraC cycles. Allo-SCT, independently of induction/consolidation therapy, should be considered an alternative treatment; (2) patients in the 'intermediate' karyotype group should receive allo-SCT; (3) patients in the 'unfavorable' karyotype group should be treated using investigational chemotherapy, considering that even allo-SCT cannot provide a significantly longer DFS, but only a trend to a better prognosis.

Adolescent↗
PubMed2001

The PFA-100 system for the assessment of platelet function in normotensive and hypertensive pregnancies.

Platelet function was studied in 30 pregnant women: 14 normotensive (C), and 16 affected by pregnancy-induced hypertension (PIH). Platelet aggregometry (PA) on platelet-rich plasma according to Born was compared with the new PFA-100 System (Dade International Inc, Miami, USA). This device evaluates platelet function (expressed in seconds as closure time, CT) in anticoagulated whole blood ex vivo at high shear rates. PA (expressed as percentage of light transmission) and CT were measured at baseline and after incubation with L-Arginine (L-Arg). MANOVA for repeated measures showed that L-Arg incubation significantly decreased PA (F=7.2, P < 0.05) and increased CT (F=6.05, P < 0.05) in the whole population of pregnant women. Moreover, we analysed separately both parameters in C and in PIH subjects. No differences in PA were found in both groups, neither at baseline nor after L-Arginine incubation. In contrast, CT was significantly longer in PIH in comparison to C before (95.9 s vs. 84 s, P < 0.05) as well after (115 s vs. 92 s, P < 0.05) L-Arginine incubation. Data from PFA-100 confirm our previous reports that during pregnancy the L-Arginine: Nitric Oxide pathway regulates platelet function. In hypertensive patients a significant decrease in platelet function was found by using the PFA-100 system.

Blood Pressure↗
PubMed2000

Bone marrow failure associated with human herpesvirus 8 infection after transplantation.

BACKGROUND: Human herpesvirus 8 (HHV-8) infection has been linked to the development of Kaposi's sarcoma and to rare lymphoproliferative disorders. METHODS: We used molecular methods, serologic methods, in situ hybridization, and immunohistochemical analyses to study HHV-8 infection in association with nonmalignant illnesses in three patients after transplantation. RESULTS: Primary HHV-8 infections developed in two patients four months after each received a kidney from the same HHV-8-seropositive cadaveric donor. Seroconversion and viremia occurred coincidentally with disseminated Kaposi's sarcoma in one patient and with an acute syndrome of fever, splenomegaly, cytopenia, and marrow failure with plasmacytosis in the other patient. HHV-8 latent nuclear antigen was present in immature progenitor cells from the aplastic marrow of the latter patient. Identification of the highly variable K1 gene sequence of the HHV-8 genome in both the donor's peripheral-blood cells and the recipients' serum confirmed that transmission had occurred. HHV-8 viremia also occurred after autologous peripheral-blood stem-cell transplantation in an HHV-8-seropositive patient with non-Hodgkin's lymphoma. Reactivation of the infection was associated with the development of fever and marrow aplasia with plasmacytosis; there was no evidence of other infections. HHV-8 transcripts and latent nuclear antigen were expressed in the aplastic marrow but not in two normal marrow samples obtained before transplantation. CONCLUSIONS: Primary HHV-8 infection and reactivation of infection may be associated with nonneoplastic complications in immunosuppressed patients.

Adult↗
PubMed2000

Molecular evidence of organ-related transmission of Kaposi sarcoma-associated herpesvirus or human herpesvirus-8 in transplant patients.

In transplant patients, Kaposi sarcoma (KS)-associated herpesvirus or human herpesvirus-8 (HHV-8) infection is associated with the development of KS, primary effusion lymphoma and Castleman disease. Whether HHV-8 is either reactivated in the recipient or transmitted by the donor has been investigated so far only by serologic studies. Thus, we addressed the issue of HHV-8 transmission in the transplantation setting by molecular methods. We exploited the high level variability of the orf-K1 gene and the polymorphism of the orf-73 gene of the HHV-8 genome to assess the genetic relatedness of the HHV-8 strains identified in the posttransplant KS lesions that developed, simultaneously, 20 months after transplantation, in 2 recipients of twin kidneys from the same cadaver donor. The 100% identity of nucleotide sequence of the most variable viral region and the presence of the same, single orf-73 type in both patients provides strong molecular evidence of organ-related transmission of HHV-8 in the setting of transplantation.

Base Sequence↗
PubMed2000

Nonmalignant disease associated with human herpesvirus 8 reactivation in patients who have undergone autologous peripheral blood stem cell transplantation.

Fever, cutaneous rash, and hepatitis-for which an infectious cause was suspected-developed in an Italian patient with non-Hodgkin lymphoma after autologous peripheral blood stem cell (PBSC) transplantation. Polymerase chain reaction (PCR) with degenerate primers for the highly conserved DNA polymerase gene of herpesviruses detected herpesvirus sequences 100% identical to human herpesvirus-8 (HHV-8) in serial cell-free serum samples, collected immediately before or concomitant with the occurrence of clinical symptoms; no other common infections were documented. The presence of the HHV-8 genome (clade C) was confirmed by PCR with HHV-8-specific primers for orf 26 and orf-K1. HHV-8 viremia was undetectable either before transplantation or when the patient was clinically asymptomatic. Semiquantitative PCR analysis showed variations of the viral load correlating with the clinical status. Anti-HHV-8 antibodies were detected before and after transplantation by an immunofluorescence assay for lytic antigens. Active HHV-8 infection may be associated with nonmalignant illness after PBSC/bone marrow transplantation.

Adult↗
PubMed2000

p53 stabilization and functional impairment in the absence of genetic mutation or the alteration of the p14(ARF)-MDM2 loop in ex vivo and cultured adult T-cell leukemia/lymphoma cells.

Human T-cell lymphotropic virus type I (HTLV-I) transforms T cells in vitro, and the viral transactivator Tax functionally impairs the tumor suppressor p53 protein, which is also stabilized in HTLV-I-infected T cells. Thus, the functional impairment of p53 is essential to maintain the viral-induced proliferation of CD4+ mature T cells. However, in the CD4+ leukemic cells of patients with adult T-cell leukemia/lymphoma (ATLL), the viral transactivator does not appear to be expressed, and p53 mutations have been found only in a fraction of patients. We sought to investigate whether p53 function is impaired, in ex vivo samples from patients with ATLL, in the absence of genetic mutations. Here we demonstrate that the p53 protein is stabilized also in ex vivo ATLL samples (10 of 10 studied) and that at least in 2 patients p53 stabilization was not associated with genetic mutation. Furthermore, the assessment of p53 function after ionizing radiation of ATLL cells indicated an abnormal induction of the p53-responsive genes GADD45 and p21(WAF1) in 7 of 7 patients. In 2 of 2 patients, p53 regulation of cell-cycle progression appeared to be impaired as well. Because p53 is part of a regulatory loop that also involves MDM2 and p14(ARF), the status of the latter proteins was also assessed in cultured or fresh ATLL cells. The p97 MDM2 protein was not detected by Western blot analysis in established HTLV-I-infected T-cell lines or ex vivo ATLL cell lysates. However, the MDM2 protein could be easily detected after treatment of cells with the specific proteasome inhibitor lactacystin, suggesting a normal regulation of the p53-MDM2 regulating loop. Similarly, p14(ARF) did not appear to be aberrantly expressed in ex vivo ATLL cells nor in any of the established HTLV-I-infected T-cell lines studied. Thus, p53 stabilization in HTLV-I infection occurs in the absence of genetic mutation and alteration of the physiologic degradation pathway of p53. (Blood. 2000;95:3939-3944)

Adult↗
PubMed2000

PCR with degenerate primers for highly conserved DNA polymerase gene of the herpesvirus family shows neither human herpesvirus 8 nor a related variant in bone marrow stromal cells from multiple myeloma patients.

The possibility has been raised that either a human herpesvirus-8 (HHV-8) variant or a novel, unidentified, gamma-herpesvirus related to HHV-8 is frequently associated with multiple myeloma (MM), which could explain the lack of antibodies to HHV-8 antigens and the discordant results from polymerase chain reaction (PCR) studies of HHV-8-specific sequences in MM patients. Thus, we used a sensitive PCR assay with degenerate primers targeting the highly conserved DNA polymerase gene of the herpesvirus family to examine the long-term cultures of bone marrow stromal cells (BMSCs) from 19 MM, 3 monoclonal gammopathies of undetermined significance and 6 control patients. Both the culture supernatant and the adherent stromal layer were examined from the 2nd until the 8th week of culture to assess the immunophenotype of the various cell types harvested for the molecular analysis. BMSCs consisted of a mixed population of fibroblast, macrophage, dendritic and endothelial cells. An amplified product of the expected size was obtained only in 3 MM cases, both in the adherent and nonadherent fractions. Direct sequencing and alignment of the nucleotide and amino acid sequences showed that the DNA sequences were 100% identical to Epstein-Barr virus (EBV) DNA. The PCR positivity was due to the presence of EBV-infected lymphoblastoid cells with plasmacytoid features, expressing the EBV-encoded latent membrane protein-1 and detectable either in the stromal cells or in the culture supernatant. Our data do not support a causal role of either HHV-8 or a novel herpesviral variant related to HHV-8 in MM.

Adult↗
PubMed2000

Late-appearing PML/RARalpha fusion transcript with coincidental t(12;13)(p13.2;q14) in acute promyelocytic leukemia lacking the t(15;17) cytogenetic anomaly.

The late appearance of a cytogenetic/molecular hallmark in human leukemias is a rare event. We report on a case of acute myeloid leukemia with morphology, immunophenotype and clinical features typical of promyelocytic subtype (APL), in which the specific PML/RARalpha gene rearrangement was molecularly detected only at second relapse of disease, without cytogenetic evidence of the t(15;17). The emergence of the PML/RARalpha gene may be therapy-related or may represent the exceptional result of a clonal evolution during progression of neoplasia. At second relapse, a novel cell clone bearing a t(12;13)(p13.2;q14) was also observed and a molecular deletion and rearrangement of a locus at 13q14, distinct from retinoblastoma (Rb1) locus, was found. In this unusual case, the PML/RARalpha product seems to be not essential for the expression of the promyelocytic phenotype at diagnosis and, when detectable, it is not the sole genetic defect.

Chromosomes, Human, Pair 12↗
PubMed2000

Detection of antibodies to human herpesvirus 8 in Italian children: evidence for horizontal transmission.

Human herpesvirus 8 (HHV-8), also known as Kaposi's sarcoma associated herpesvirus (KSHV), has been shown to be the causative agent for Kaposi's sarcoma (KS) and to be more prevalent in populations or risk groups at increased risk for KS. HHV-8 infection is rare in children from the US and the UK, but has been reported in African children. In this study we examine HHV-8 infection in children from Italy, a country with an elevated prevalence of HHV-8 in adults and high socio-economic conditions.

Adolescent↗
PubMed2000

Detection of circulating tumor cells by reverse transcriptase polymerase chain reaction of maspin in patients with breast cancer undergoing conventional-dose chemotherapy.

PURPOSE: To establish, in patients with breast cancer subjected to primary conventional chemotherapy and enrolled in a prospective study, the mobilizing effect of therapy on potentially neoplastic cells by means of a reverse transcriptase polymerase chain reaction (RT-PCR) assay for mRNA of maspin, a protein related to the serpin family of protease inhibitors. PATIENTS AND METHODS: Peripheral-blood samples were collected from 30 patients with histologically proven breast cancer before and 4 and 8 days after conventional chemotherapy for three consecutive courses. A total of 216 samples were screened for the presence of maspin mRNA by RT-PCR. RESULTS: Before therapy, all samples but one were negative. After chemotherapy, 11 patients (38%) had positive samples. No difference in the rate of positivity was observed between groups defined according to initial stage, type of chemotherapy, Ki-67-related proliferative activity, or CA 15.3 expression. CONCLUSION: Our results confirm that RT-PCR for maspin mRNA is a sensitive assay for the study of circulating potentially neoplastic mammary cells in patients with breast cancer. Moreover, our findings indicate a marked effect of conventional-dose chemotherapy on the mobilization of these cells in breast tumors. In our series of patients, this phenomenon does not seem to be associated with other known risk factors. Finally, the data suggest, without proving, an association between the presence of circulating maspin positive cells and a higher risk of disease progression. If this association could be confirmed, then the assay could have prognostic significance. However, larger confirmatory studies are necessary.

Adult↗
PubMed2000

Fatal herpesvirus-6 encephalitis in a recipient of a T-cell-depleted peripheral blood stem cell transplant from a 3-loci mismatched related donor.

Human herpesvirus-6 (HHV-6), like all the other herpes viruses, remains latent in host cells after primary infection but can be reactivated in immunocompromised patients causing fever, skin rash, bone marrow (BM) suppression, pneumonitis, sinusitis and meningoencephalitis. We describe the case of a man with chronic myelogenous leukemia who developed encephalitis associated with acute graft-versus-host disease two months after a T-cell-depleted mismatched peripheral blood stem cell transplant. Magnetic resonance images of the brain revealed multiple bilateral foci of signal abnormality. HHV-6 was the only pathogen detected in cerebrospinal fluid by PCR. Treatment with both ganciclovir and foscarnet was unsuccessful and the patient gradually deteriorated and died. Other cases of HHV-6 encephalitis after bone marrow transplantation are reviewed.

Cytomegalovirus Infections↗
PubMed1999

Expression of cell-homologous genes of human herpesvirus-8 in human immunodeficiency virus-negative lymphoproliferative diseases.

Human herpesvirus-8 (HHV-8) genome encodes for genes homologous to human cellular genes such as interleukin-6 (IL-6), Cyclin-D, BCL-2, and IL-8 receptor (G-protein-coupled receptor [GCR]). We used reverse transcriptase-polymerase chain reaction to study the expression of these viral genes in lymphoproliferative disorders associated with HHV-8 infection. None of these genes was expressed in 1 case of benign, localized Castleman's disease (CD), and only viral IL-6 and viral Cyclin-D were transcribed in 2 cases of benign lymphadenopathies with giant germinal center hyperplasia and increased vascularity. In contrast, all 4 genes were transcribed in 1 case of multicentric CD of plasma cell type with aggressive clinical course and in 1 primary effusion lymphoma cell line. Our study provides the evidence that various HHV-8 genes, homologous to cellular genes involved in control of proliferation and apoptosis, may be differently expressed in different lymphoid disorders in vivo.

Antigens, CD↗
PubMed1999

Fine mapping of an apparently targeted latent human herpesvirus type 6 integration site in chromosome band 17p13.3.

An unusually high level of latent HHV-6 infection has been documented in the peripheral blood and/or bone marrow cells of a small group of patients with predominantly malignant lymphoid disorders, and in at least one healthy individual. We have shown previously in peripheral blood mononuclear cells (PBMCs) of three patients, two with a history of lymphoma and one with multiple sclerosis, a specific target site for latent integration of the full-length HHV-6 viral genome on the distal short arm of chromosome 17, in band p13.3. Fluorescence in situ hybridization (FISH) procedures were used to map more precisely the location of the viral integration site in one of those patients, relative to two known oncogenes mapped previously, namely CRK, and the more telomeric ABR oncogene. It is shown that the HHV-6 integration site is located at least 1,000 kb telomeric of ABR, and is very likely to map close to or within the telomeric sequences of 17p. This finding is significant given that human telomeric-like repeats flank the terminal ends of the HHV-6 genome. Cytogenetic studies showed evidence of karyotype instability in the peripheral blood cells infected latently.

Binding Sites↗
PubMed1999

The oncogenic 30 and 69 bp deletion variants of the EBV LMP-1 gene are common in HIV-negative lymphoproliferations, both malignant and benign.

BACKGROUND: In vitro studies have shown that the 30 and 69 base pair (bp) deletion variants of the latent membrane protein (LMP)-1 gene of the Epstein-Barr virus (EBV) have a higher transforming capacity than the wild-type variant. In recent years these studies have triggered an in vivo search for such potentially oncogenic variants in lymphoid tissues. PATIENTS AND METHODS: We used polymerase chain reaction (PCR) to investigate the prevalence of LMP-1 gene variants in EBV-positive lymph nodes from 60 HIV-negative Italian patients with benign and malignant lymphoid disorders. RESULTS: The 30 bp variant was detected in 10 of 39 (25.6%) malignant lymphomas but also in 4 of 13 (30%) reactive lymphadenitis with follicular hyperplasia. Of note is the fact that the 69 bp variant was detected in three cases of malignant lymphoproliferation but also in two cases of localized Castleman's disease of hyalin vascular type. CONCLUSIONS: The molecular detection of the oncogenic variants of the LMP-1 gene in a lymph node biopsy as an indicator of the aggressiveness of the EBV-associated lymphoproliferative disease must be considered with caution. The relatively high frequency of the 69 bp variant in our series compared with that reported in the literature probably reflects a different incidence of LMP-1 variants in healthy populations from different geographical areas.

Biopsy↗