Search PubMed⌕ Search

Biomedical subjects

Giovanni Martinelli

Publications and source records attributed to Giovanni Martinelli.

At least 91 records · Page 5Linked to original sources
PubMed2003

Novel translocations that disrupt the platelet-derived growth factor receptor beta (PDGFRB) gene in BCR-ABL-negative chronic myeloproliferative disorders.

The BCR-ABL-negative chronic myeloproliferative disorders (CMPD) and myelodysplastic/myeloproliferative diseases (MDS/MPD) are a spectrum of related conditions for which the molecular pathogenesis is poorly understood. Translocations that disrupt and constitutively activate the platelet-derived growth factor receptor beta(PDGFRB) gene at chromosome band 5q33 have been described in some patients, the most common being the t(5;12)(q33;p13). An accurate molecular diagnosis of PDGFRB-rearranged patients has become increasingly important since recent data have indicated that they respond very well to imatinib mesylate therapy. In this study, we have tested nine patients with a CMPD or MDS/MPD and a translocation involving 5q31-33 for disruption of PDGFRB by two-colour fluorescence in situ hybridization (FISH) using differentially labelled, closely flanking probes. Normal control interphase cells gave a false positive rate of 3% (signals more than one signal width apart). Six patients showed a pattern of one fused signal (from the normal allele) and one pair of signals separated by more than one signal width in > 85% of interphase cells, indicating that PDGFRB was disrupted. These individuals had a t(1;5)(q21;q33), t(1;5)(q22;q31), t(1;3;5)(p36;p21;q33), t(2;12;5)(q37;q22;q33), t(3;5) (p21;q31) and t(5;14)(q33;q24) respectively. The remaining three patients with a t(1;5)(q21;q31), t(2;5)(p21;q33) and t(5;6)(q33;q24-25) showed a normal pattern of hybridization, with > or = 97% interphase cells with two fusion signals. We conclude that two-colour FISH is useful to determine the presence of a PDGFRB rearrangement, although, as we have shown previously, this technique may not detect subtle complex translocations at this locus. Our data indicate that several PDGFRB partner genes remain to be characterized.

Chromosomes, Human, Pair 1↗
PubMed2003

Efficacy and safety of darbepoetin alfa in anaemic patients with lymphoproliferative malignancies: a randomized, double-blind, placebo-controlled study.

This phase 3, randomized, double-blind, placebo-controlled study was designed to evaluate the efficacy and safety of darbepoetin alfa in anaemic patients with lymphoproliferative malignancies. Patients (n = 344) with lymphoma or myeloma received darbepoetin alfa 2.25 microg/kg or placebo s.c., once weekly for 12 weeks. The percentage of patients achieving a haemoglobin response was significantly higher in the darbepoetin alfa group (60%) than in the placebo group (18%) (P < 0.001), regardless of baseline endogenous erythropoietin level. However, increased responsiveness was observed in patients with lower baseline erythropoietin levels. Darbepoetin alfa also resulted in higher mean changes in haemoglobin than placebo from baseline to the last value during the treatment phase (1.80 g/dl vs 0.19 g/dl) and after 12 weeks of treatment (2.66 g/dl vs 0.69 g/dl). A significantly lower percentage of patients in the darbepoetin alfa group received red blood cell transfusions than in the placebo group (P < 0.001). The efficacy of darbepoetin alfa was consistent for patients with lymphoma or myeloma. Improvements in quality of life were also observed with darbepoetin alfa. The overall safety profile of darbepoetin alfa was consistent with that expected for this patient population. Darbepoetin alfa significantly increased haemoglobin and reduced red blood cell transfusions in patients with lymphoproliferative malignancies receiving chemotherapy.

Aged↗
PubMed2003

Chlorambucil in combination with induction and maintenance rituximab is feasible and active in indolent non-Hodgkin's lymphoma.

We investigated the toxicity and efficacy of the chimaeric anti-CD20 antibody rituximab in combination with standard-dose chlorambucil in newly diagnosed and relapsed/refractory indolent B-cell lymphoma patients. A total of 29 patients (15 newly diagnosed and 14 relapsed/refractory) with low-grade or follicular B-cell non-Hodgkin's lymphoma (NHL) were included in this phase II study. Therapy consisted of chlorambucil 6 mg/m2/d for 6 consecutive weeks in combination with a standard 4-weekly rituximab administration schedule in the induction phase. Patients responding to the induction therapy received four additional cycles with chlorambucil (6 mg/m2/d for 2 weeks/month) plus rituximab (once a month). Twenty-six patients (89%) completed the treatment; only one patient discontinued treatment because of haematological toxicity. At the end of the study, the dose of chlorambucil had to be reduced in seven patients (27%) and six patients (23%) required a delay in further treatment, as a result of toxicity during consolidation therapy. Only one patient was withdrawn from the study because of progressive disease; the 27 patients evaluable for response at the end of consolidation achieved a clinical response (63% complete response and 26% partial response). A significant CD4+ and CD56+ depletion was observed after induction and during consolidation therapy; two herpes zoster virus infections and one perianal abscess represented major infectious morbidities registered during the study. Based on our preliminary data, the combination of chlorambucil with rituximab seemed to be well tolerated and active. Its definitive role in the treatment of low-grade NHL should be further evaluated in randomized trials.

Adult↗
PubMed2003

Interferon-alfa for chronic myeloid leukemia.

Interferon-alfa (IFNalpha) became the first-line agent for the treatment of chronic myeloid leukemia (CML) because it prolongs survival significantly compared to conventional chemotherapy (CHT). Responses to IFNalpha and the benefits from achieving a response are greater in low-risk than in high-risk patients. The best therapeutic results are obtained in low-risk patients who achieve a complete hematologic response (CHR) within 3 to 6 months, a major cytogenetic response (MCgR) within 1 year, and a complete cytogenetic response (CCgR) thereafter. Cytogenetic responses (CgRs) to IFNalpha are stable and durable, so that about 50% of complete responders become long-term survivors. Combining IFNalpha with other drugs, like arabinosyl cytosine (AC), and with other treatments, like autologous stem cell transplantation (autoSCT), may provide additional benefit, although this has not been proven. The biologic and molecular bases of the action of IFNalpha are still poorly understood, but are worth investigating further to determine whether it will still have a therapeutic role when used in combination with the protein tyrosine kinase inhibitors and other new agents.

Antineoplastic Agents↗
PubMed2003

The cytogenetic response as a surrogate marker of survival.

In the management of chronic myeloid leukemia (CML), cytogenetic response (CgR) has been recognized as an important prognostic factor and is used in predicting patient outcome. Imatinib (Gleevec) (formerly STI571), a potent inhibitor of BCR-ABL, is very effective in inducing CgRs in chronic-phase CML patients, even in late chronic-phase patients in whom interferon (IFN) was unsuccessful. This review describes the intrinsic value of a CgR following different forms of nontransplant treatment options for CML. Achievement of major CgR is predictive of prolonged survival with imatinib. In addition, patient prognostic risk score (Sokal or Euro risk score) affects patient outcome. Low-risk patients survive longer than non-low-risk patients given the same CgR. Preliminary results from studies with imatinib are superior and CgR remains an important surrogate marker of survival in the imatinib era.

Benzamides↗
PubMed2003

Rapid detection of Flt3 mutations in acute myeloid leukemia patients by denaturing HPLC.

BACKGROUND: fms-related tyrosine kinase 3 (Flt3) is the most commonly mutated gene in human acute myeloid leukemia (AML) and has been implicated in its pathogenesis. Because screening of Flt3 in AML patients by PCR followed by gel electrophoresis is time-consuming and fails to detect some very small internal tandem duplications (ITDs), we developed a method for screening of FLT3 receptor mutations with PCR plus denaturing HPLC (D-HPLC). METHODS: Total mRNAs extracted from 34 AML patients were first analyzed for the presence of juxtamembrane length mutations and tyrosine kinase domain point mutations by a conventional method involving PCR amplification, restriction enzyme digestion, and agarose gel electrophoresis (PCR-RED-AGE). Subsequently, the same patient panel was analyzed by D-HPLC, using specifically designed primers and optimized running temperatures for the length and point mutation analysis. RESULTS: Thirty-four patients were analyzed by PCR-RED-AGE; 9 were positive for known Flt3 mutations: 6 of 34 (18%) for ITDs in exon 14 and 3 of 34 (9%) for point mutations in exon 20. The same patient panel was analyzed by D-HPLC, and additional nucleotide changes were discovered; in total, 14 sequence variations were identified: 7 of 34 (21%) for ITDs in exon 14; 2 of 34 (6%) for point mutations in exon 20; 1 of 34 (3%) for a new point mutation in exon 16; and 4 of 34 (12%) for polymorphisms in exons 13 and 14. Direct sequencing analysis identified nucleotide alterations in each of the "D-HPLC positives" but in none of the "D-HPLC negatives", yielding a specificity and sensitivity of 100% for D-HPLC-based screening. CONCLUSIONS: This novel D-HPLC-based procedure, which is optimized for identification of new point mutations in the catalytic and regulatory domains of FLT3 receptor, could potentially be useful for studies involving precise genotype determination, which could be critical for selection of innovative AML therapies targeting the FLT3 protein.

Acute Disease↗
PubMed2003

Minor increases in plasma troponin I predict decreased left ventricular ejection fraction after high-dose chemotherapy.

BACKGROUND: Increased cardiac troponin I (cTnI) in patients treated with high-dose chemotherapy (HDCT) for aggressive malignancy has been proposed as an early marker of late HDCT-induced cardiac dysfunction. We investigated whether cTnI measured by the Stratus CS (Dade Behring) would allow detection of minimal cTnI increases in patients treated with HDCT. METHODS: Plasma cTnI concentrations were determined in 179 consecutive patients before HDCT, at the end of the treatment, and after 12, 24, 36, and 72 h. Cardiac function was explored by echocardiography, and left ventricular ejection fraction (LVEF) was recorded during follow-up. The greatest variation in LVEF from the baseline value was used as a measure of cardiac damage. RESULTS: In 99 healthy volunteers, the 99th percentile was at 0.07 microg/L. On the basis of ROC curve analysis (area under the curve, 0.89), a cutoff of 0.08 microg/L was chosen (sensitivity, 82%; specificity, 77%). cTnI > or =0.08 microg/L occurred in 57 patients (32%) with echocardiographic monitoring revealing a mean decrease in LVEF of 18%. In comparison, the group of cTnI-negative patients had a mean decrease in LVEF of 2.5% (P <0.001). CONCLUSIONS: Plasma cTnI, as measured with the Stratus CS, can detect minor myocardial injury in patients treated with HDCT.

Antineoplastic Agents↗
PubMed2003

Molecular characterization of a non-Babesia divergens organism causing zoonotic babesiosis in Europe.

In Europe, most reported human cases of babesiosis have been attributed, without strong molecular evidence, to infection with the bovine parasite Babesia divergens. We investigated the first known human cases of babesiosis in Italy and Austria, which occurred in two asplenic men. The complete 18S ribosomal RNA (18S rRNA) gene was amplified from specimens of their whole blood by polymerase chain reaction (PCR). With phylogenetic analysis, we compared the DNA sequences of the PCR products with those for other Babesia spp. The DNA sequences were identical for the organism from the two patients. In phylogenetic analysis, the organism clusters with B. odocoilei, a parasite of white-tailed deer; these two organisms form a sister group with B. divergens. This evidence indicates the patients were not infected with B. divergens but with an organism with previously unreported molecular characteristics for the 18S rRNA gene.

Animals↗
PubMed2003

Continuous infusion of endostatin inhibits differentiation, mobilization, and clonogenic potential of endothelial cell progenitors.

PURPOSE: We investigated the effect of endostatin on differentiation, mobilization, and clonogenic potential of circulating endothelial cell (EC) progenitors, and whether the effect of endostatin was improved by continuous infusion (CI) versus bolus administration. EXPERIMENTAL DESIGN: Four-color flow cytometry and clonogenic EC cultures were used to study EC progenitors in tumor-free mice, tumor-bearing immunodeficient mice, and immunodeficient mice xenotransplanted with human bone marrow (BM) cells. RESULTS: Endostatin significantly reduced the number of circulating EC progenitors in tumor-free BALB/c mice. The effect of endostatin on EC progenitors was enhanced significantly in mice treated with CI drug treatment. When immunodeficient mice xenotransplanted with human BM cells were treated with CI of endostatin we observed a significant decrease in the engraftment and differentiation of human BM-derived EC progenitors. Numbers of circulating EC progenitors increased 7-fold in immunodeficient mice bearing human lymphoma. In this preclinical model, treatment with CI of endostatin inhibited host murine EC progenitor mobilization and human tumor growth. Furthermore, the clonogenic potential of EC progenitors was impaired severely. CONCLUSIONS: Endostatin is a potent inhibitor of the mobilization and clonogenic potential of human and murine EC progenitors, and its preclinical activity is increased significantly in CI compared with bolus administration. These observations might be useful in the design of future clinical trials.

Animals↗
PubMed2003

Risk and early cytogenetic response to imatinib and interferon in chronic myeloid leukemia.

BACKGROUND AND OBJECTIVES: We compared the early cytogenetic response (CgR) to a combination of imatinib mesylate (Glivec, Novartis Pharma, Basel, Switzerland) and a pegylated form of human recombinant interferon-alpha2b (pegIFN-alpha2b, PegIntron, Schering Plough, Kenilworth, New Jersey, USA) with the relative risk, either according to Sokal's or Euro scoring systems. DESIGN AND METHODS: Seventy-seven patients with early chronic phase, previously untreated, Ph-positive chronic myeloid leukemia (CML) received a combination of imatinib mesylate (400 mg/day) and pegIFN-alpha2b (3 consecutive cohorts treated with 50, 100 or 150 mg/weekly). Fifty-seven patients have completed the first 6 months of treatment and are evaluable for CgR. RESULTS: After 6 months of treatment, the overall major CgR rate was 89% and 90% in low risk patients (Sokal's and Euro, respectively), 76 and 59% in intermediate risk and 23% and 17% in high risk patients. These differences were significant (p=0.0001 for Sokal and 0.001 for e). INTERPRETATION AND CONCLUSIONS: For the first time, these data suggest that the early CgR rate to a imatinib mesylate-based regimen is significantly risk-related.

Adolescent↗
PubMed2003

Stroma cells: a novel target of herceptin activity.

PURPOSE: Stroma cells play a relevant role in tumor development and progression. We investigated the activity of herceptin (HER), a humanized monoclonal antibody widely used for the treatment of HER2-overexpressing epithelial cancer, toward stroma cell lines L87/4 and L88/5. EXPERIMENTAL DESIGN: We studied the antiproliferative potential of HER and role of human serum in HER activity. We also investigated the ability of HER to alter ancillary functions of L87/4 and L88/5, such as support to long-term hematopoiesis, growth factor production, breast cancer cell adhesion, and proliferation. RESULTS: Flow cytometry showed that HER2 membrane expression in L87/4 and L88/5 stroma cells was intermediate between the expression in HER2-negative/dim MCF-7 breast cancer cells and HER2-bright SK-BC3 breast cancer cells. HER2 gene amplification was not detected by fluorescence in situ hybridization in either stromal cell lines. HER significantly inhibited L87/4 and L88/5 proliferation. Mean ID(50)s were found to be 2000 and 1700 micro g/ml for L87/4 and L88/5, respectively, after 3-day exposure and 800 micro g/ml for both cell lines after 9-day exposure. The presence of 10% human serum in the culture increased HER inhibitory activity. IC(50) of stroma cells was found to be intermediate between HER2-bright breast cancer cells (SK-BC3) and HER2-negative/dim breast cancer cells (MCF-7). The drug did not significantly affect the ability of stroma cells to support long-term hematopoiesis in the cobblestone area forming cell assay. In contrast, in coculture assay, MCF7 cells demonstrated a worse adhesion and growth capability on HER-treated stroma layers when compared with untreated stroma. Moreover, HER significantly reduced vascular endothelial growth factor production by L88/5 cells. CONCLUSIONS: Our data support the novel finding that HER may have a relevant activity against stroma cells.

Antibodies, Monoclonal↗
PubMed2003

p53 loss of function enhances genomic instability and accelerates clonal evolution of murine myeloid progenitors expressing the p(210)BCR-ABL tyrosine kinase.

BACKGROUND AND OBJECTIVES: The p210 bcr-abl fusion protein has a key role in the pathogenesis of chronic myeloid leukemia (CML). However, its influence on disease progression to blast crisis is marginal and mostly due to its effect of impairing the genomic stability of clonal myeloid progenitors through pathways still largely unknown. DESIGN AND METHODS: To elucidate the role of p53 in CML progression we generated, from the 32D murine myeloid cell line, several clones co-expressing the E6 product gene of human papilloma virus (HPV) 16, which abrogates p53 function, and a temperature-sensitive bcr-abl construct encoding a fully active p210 protein only at the permissive temperature of 33 degrees C. RESULTS: Co-expression of the two proteins resulted in a significant enlargement of the G(2)/M phase of cell cycle and in the appearance of a poly-aneuploid cell population. Furthermore, with continuous in vitro passages the p210 tyrosine kinase became dispensable for growth. Increased levels of cyclin B(1) and enhanced activity of its associated cyclin-dependent kinase (cdc2) became apparent during the clonal evolution of p210 bcr-abl-transduced 32D cell clones lacking p53. INTERPRETATION AND CONCLUSIONS: The acceleration of clonal evolution of p210 bcr-abl-transduced 32D myeloid progenitors associated with p53 functional abrogation is consistent with oncosuppressor loss having a key role in CML progression. This would allow emergence of additional genomic aberrations which would lead to the fully transformed phenotype of blast crisis. Deregulated activity of the cyclin B1-cdc2 complex may be involved in the loss of temporal co-ordination of mitotic events and further free the barrier to genomic instability of CML clonal myeloid progenitors lacking p53.

Aneuploidy↗
PubMed2003

Association of 3q21q26 syndrome with different RPN1/EVI1 fusion transcripts.

BACKGROUND AND OBJECTIVES: Patients with acute myeloblastic leukemia (AML) with features of myelodysplastic syndrome and abnormalities of megakaryocytopoiesis often have cytogenetic aberrations of 3q21 and 3q26 bands involving the paracentric inversion [inv(3) (q21q26)] or a reciprocal translocation [t(3;3) (q21;q26)]. These abnormalities frequently cause inappropriate expression of the EVI1 gene located at 3q26. Other genes that have been implicated at the rearrangement breakpoint are GR6 and RPN1 (both on 3q21). The aim of this study was to investigate the expression of the EVI1 fusion genes in AML patients with 3q21q26 syndrome. DESIGN AND METHODS: We used reverse transcription polymerase chain reaction to evaluate the expression of EVI1 and GR6, and particularly of the fusion genes RPN1-EVI1 and GR6-EVI1 in 9 AML patients with either inv(3)(q21q26) (7 cases) or t(3;3)(q21;q26) (2 cases). RESULTS: EVI1 and GR6 were always expressed, as was RPN1-EVI1; GR6-EVI1 was absent. In 8/9 patients, the part of EVI1 retained in RPN1-DEVI1 contained blocks B and C of the PR domain commonly found in the MDS1-EVI1 gene. In the remaining patient [with inv(3) (q21q26)], only block C was retained: we named this variant fusion gene RPN1-DEVI1. This patient lacked the micromegakaryocytopoiesis frequently found in 3q21q26 syndrome. INTERPRETATION AND CONCLUSIONS: These findings support the hypothesis that EVI1 activation plays a dominant role in the pathogenesis of the 3q21q26 syndrome. EVI1 expression might occur either as a consequence of rearrangements leading to the formation of different fusion transcripts, such as RPN1-EVI1 and RPN1-DEVI1 or following disruption of the PR activation domain of the MDS1-EVI1 gene.

Adult↗
PubMed2003

The Assisi Chartula by the hand of Saint Francis: non-destructive characterization by spectroscopic spectrometric and optical methods.

Just two examples of writings by the hand of S. Francesco are known to exist: a letter to Brother Leone, kept in the archives of Spoleto cathedral and the Chartula, displayed in the Hall of Reliquaries at Assisi's Sacro Convento. For the first time in its history the Chartula has undergone a series of non-destructive analyses, with the object of establishing its current state of conservation and the types of inks used in its making. A new display case has been designed and built for the improved conservation of this precious document. The new housing substitutes an ancient case, which was located inside the original reliquary.

Famous Persons↗