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M Luppi

Publications and source records attributed to M Luppi.

At least 37 records · Page 2Linked to original sources
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

Variability and evolution of Kaposi's sarcoma-associated herpesvirus in Europe and Africa. International Collaborative Group.

OBJECTIVE: To study the evolution of Kaposi's sarcoma-associated herpesvirus (KSHV) or human herpesvirus type 8 in Europe and Africa. DESIGN AND METHODS: PCR and sequence analysis of the variable viral membrane glycoprotein gene K1 in 58 tumour and peripheral blood samples from patients with AIDS-related Kaposi's sarcoma (KS), 'classic' (HIV-negative) KS, transplant KS, Multicentric Castleman's Disease, other lymphoproliferative disorders, and healthy KSHV-infected individuals from the UK, Denmark, Sweden, Italy, Spain, Iceland, The Faroe Islands, Greece, The Gambia and Uganda. RESULTS: Three major groups of K1 sequences were found: A, B and C, as defined previously. The K1 gene has evolved, both within and between these three groups, under positive selection. KSHV group B strains predominate in Africa and are more distant from groups A and C, found in Europe, than A and C are from each other. Within group C two subgroups, C' and C", can be identified. Subgroup C" is more closely related to group A in a region of the K1 protein and appears to be phylogenetically close to the branchpoint between A and C. Group A and C strains are currently found in both HIV-1-infected and -uninfected Europeans, and were already present in Europe before the start of the AIDS epidemic. We found some examples of closely related K1 sequences in Italy and Denmark, but in general KSHV strains in Europe did not cluster geographically. CONCLUSION: KSHV strains in East and West Africa are closely related but phylogenetically distant from those in Europe. The two major KSHV groups in Europe are more closely related, with some strains adopting an intermediate phylogenetic position. In Europe, KSHV strains may have been disseminated at least several decades ago. Variability in the K1 region is driven by selection and does not correlate with different KSHV-related pathologies or geographic regions where clinically more aggressive HIV-negative KS ('endemic' KS) is more common.

AIDS-Related Opportunistic Infections↗
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↗
PubMed1999

Human herpesvirus 6 latently infects early bone marrow progenitors in vivo.

We have studied the in vivo tropism of human herpesvirus 6 (HHV-6) for hemopoietic cells in patients with latent HHV-6 infection. Having used a variety of cell purification, molecular, cytogenetic, and immunocytochemical procedures, we report the first evidence that HHV-6 latently infects early bone marrow progenitor cells and that HHV-6 may be transmitted longitudinally to cells which differentiate along the committed pathways.

Antigens, CD34↗
PubMed1999

Missense mutations in the PML/RARalpha ligand binding domain in ATRA-resistant As(2)O(3) sensitive relapsed acute promyelocytic leukemia.

BACKGROUND AND OBJECTIVE: Acute promyelocytic leukemia is characterized by the chromosomal translocation t(15;17) which yields the fusion product PML/RARa. All-trans retinoic acid probably induces differentiation of atypical promyelocytes and clinical remission in APL patients by binding to the ligand binding domain (LBD) of the RARa portion of the PML-RARa chimeric protein. Structural alterations of the LBD of the PML/RARa have been revealed in ATRA-resistant APL cell lines and in a few APL patients with acquired clinical resistance to ATRA therapy. Two APL relapsed patients with clinical resistance to ATRA therapy were evaluated for the presence of nucleotide mutations in the LBD of PML/RARa gene and then treated with arsenic trioxide (As2O3). DESIGN AND METHODS: DNA fragments from the LBD of the PML/RARa chimeric transcript were obtained by reverse-transcribed polymerase chain reaction. Direct sequencing was performed by an unambiguous bi-directional automatic analysis. Samples representative of APL onset and relapse were analyzed from both patients. RESULTS: In both patients, at the ATRA-resistant relapse, a missense point mutation in the LBD of the PML/RARa gene was found. The mutations, absent at APL onset, led to an Arg272Gln and to an Arg276Trp amino acid substitution, according to the sequence of the RARa protein. Both patients had complete clinical and hematologic remission after treatment with As2O3. INTERPRETATION AND CONCLUSIONS: LBD missense mutations appear to be a significant mechanism of acquired ATRA-resistance in vivo, closely related to clinical APL relapse. The two cases reported here provide the first in vivo evidence of APL relapsed patients, who have become ATRA-resistant for molecular reasons, being sensitive to arsenic trioxide.

Adult↗
PubMed1998

Absence of a directly causative role for human herpesvirus 7 in human lymphoma and a review of human herpesvirus 6 in human malignancy.

In search of a (new) viral etiological agent, we screened 64 lymph node samples from Hodgkin's disease (HD) and 43 samples (32 lymph node and 11 skin biopsies) from non-Hodgkin's lymphoma (NHL) for human herpesvirus 7 (HHV-7). Twenty-nine control samples were tested as well, including 17 with benign lymphadenopathy. None of the samples tested positive by Southern blot hybridization using HHV-7-specific probes. We conclude that there is no major HHV-7 load in human lymphoma and that HHV-7 is not likely to be directly involved in its etiology. This is in contrast to a small minority of human lymphoproliferative diseases in which HHV-6 can be found at high copy number, but in which an etiological role is still uncertain.

Herpesviridae Infections↗