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Biomedical subjects

M Fizzotti

Publications and source records attributed to M Fizzotti.

35 records · Page 2Linked to original sources
PubMed1994

Simultaneous expression of RBTN-2 and BCR-ABL oncogenes in a T-ALL with a t(11;14)(p13;q11) and a late-appearing Philadelphia chromosome.

Cytogenetic analysis of a pediatric patient with T-cell acute lymphoblastic leukemia (T-ALL) revealed a mosaic karyotype, 47,XX,+17,t(11;14)(p13;q11)/47,XX,+17,t(9;22)(q34;q11),t(11;14) (p13;q11). DNA blot analysis was used to examine the break-point within the BCR gene on chromosome 22 and showed that the breakpoint occurred within the 20-kb minor breakpoint cluster region (m-bcr) located within the first intron of the BCR gene. Immunoprecipitation analysis demonstrated that the leukemic cells expressed the P185 BCR-ABL protein tyrosine kinase. P185 BCR-ABL has previously been shown to be expressed in most cases of Ph+ acute leukemia of myeloid and B-progenitor origin. Here, we demonstrate for the first time that P185 can also be expressed in the T-cell lineage. DNA blot hybridization was also used to characterize the t(11;14) translocation. This showed rearrangement on chromosome 11 within the T-ALLbcr region, upstream of the RBTN-2 gene. Polymerase chain reaction revealed the presence of RBTN-2 transcripts in the leukemic cells. Finally, comparison of the T-ALLbcr, BCR-ABL, IGH, TCR beta and gamma gene rearrangements in leukemic cells obtained at the time of diagnosis and at first relapse showed that relapse occurred in a leukemic clone indistinguishable from the major Ph+ clone involved at diagnosis. Together, these data support a multistep pathogenesis in which the Philadelphia (Ph) chromosome translocation appeared subsequent to the +17 and t(11;14) and imparted a growth advantage over the Ph-negative cells that carried these abnormalities.

Base Sequence↗
PubMed1993

Simultaneous demonstration of the Philadelphia chromosome in T, B, and myeloid cells.

A patient presented with lymphoblastic lymphoma in lymph-nodes and chronic myelogenous leukemia (CML) in narrow and peripheral blood. All marrow and unstimulated peripheral blood cells contained the Philadelphia chromosome[t(9:22)]. Lymphoma cells were analyzed by flow cytometry and were identified as T cells (CD2+CD5+CD7+CD34+). All fresh lymphoma cells contained the t(9:22) translocation. Cultures of purified peripheral blood T and B cells and specifically stimulated NK cells revealed that 59% of the B cells, 10% of the NK cells, and none of the normal T cells contained the translocation. The lack of translocation in normal peripheral T cells is attributed to their long lifespan. No rearrangement of immunoglobulin or T cell receptor beta or gamma genes was found in either the leukemia or lymphoma cells. Analysis of the DNA from cryopreserved lymphoma biopsy showed clonal rearrangement within the common breakpoint cluster region of the bcr gene identical to the bcr rearrangement in DNA from leukemia blood cells. The data support the concept that T and B cells originate in the patient's totipotent stem cell from which the CML is also derived.

Antigens, CD↗
PubMed1993

BCR-ABL and v-abl oncogenes induce distinct patterns of thymic lymphoma involving different lymphocyte subsets.

The human BCR-ABL oncogenes encoded by the Philadelphia chromosome (Ph) affect the pathogenesis of diverse types of leukemia and yet are rarely associated with T-lymphoid leukemia. To determine whether BCR-ABL kinases are inefficient in transforming T lymphocytes, BCR-ABL-expressing retroviruses were injected intrathymically into mice. Thymomas that expressed BCR-ABL kinase developed after a relatively long latent period. In most thymomas, deletion of 3' proviral sequences resulted in loss of tk-neo and occasionally caused expression of kinase-active carboxy-terminally truncated BCR-ABL oncoprotein. In contrast, deletion of 3' proviral sequences was not observed in thymomas induced with Abelson murine leukemia virus (A-MuLV). BCR-ABL viruses induced distinct patterns of disease and involved different thymocyte subsets than A-MuLV and Moloney murine leukemia virus (Mo-MuLV). While Mo-MuLV only induced Thy-1+ thymomas, v-abl- and BCR-ABL-induced thymomas often contained mixed populations of B220+ and Thy-1+ lymphocytes in the same tumor. In most v-abl and BCR-ABL tumors, Thy-1+ lymphoid cells expressed CD8 and a continuum of CD4 ranging from negative to positive. Conversely, Mo-MuLV thymomas contained distinct populations of CD4+ cells that were either CD8+ or CD8-. A-MuLV-transformed T-lymphoid cells did not express the CD3/T-cell receptor complex, while BCR-ABL tumors were CD3+. Thus, BCR-ABL viruses preferentially induce somewhat more differentiated T lymphocytes than are transformed by A-MuLV. Furthermore, rare B220+ lymphocytes may represent preferred v-abl and BCR-ABL transformation targets in the thymus.

Animals↗
PubMed1991

Biochemical and immunological responses of hairy cell leukemia patients to interferon beta.

Ten hairy-cell leukemia patients were treated with interferon beta (IFN-beta) at a dose rate of 2 x 10(6) IU/m2 x 5 days for 4 weeks (induction therapy) and, thereafter, at the same dose three times a week for 11 months (maintenance therapy). The effect of this treatment on serum neopterin, beta 2-microglobulin, (2'-5')oligoadenylate [(2'-5')An] levels, intracellular (2'-5')An values and human Mx protein synthesis was analysed. There were significant rises in serum neopterin and (2'-5')An levels during both induction and maintenance, whereas beta 2-microglobulin levels rose only during induction. Rises in intracellular (2'-5')An were documented mainly during induction, but they were not significantly higher than pretherapy values. IFN beta provoked an increase in human Mx protein synthesis over the entire induction-maintenance period, but was only significantly higher than baseline during induction. All markers proved useful for monitoring the effects of IFN beta dose schedules, but were not predictive of clinical outcome. Natural killer activity and IFN gamma production, which were initially defective, followed a different trend from that of the other factors studied, in that increases were documented only late in the course of therapy when the disease was already in remission.

2',5'-Oligoadenylate Synthetase↗
PubMed1991

Selective purging by human interleukin-2 activated lymphocytes of bone marrows contaminated with a lymphoma line or autologous leukaemic cells.

The ability of recombinant interleukin 2 (rIL2) activated lymphocytes (LAK) to purge BM samples contaminated by tumour cells was evaluated. Human BM mononuclear cells were contaminated with 10% of the lymphoma line CA46 and then cultured in liquid medium containing 1000 U/ml of rIL2 and/or LAK autologous to the used BM. At the end of coculture the growth of residual tumour cells and of CFU-GM were evaluated by clonogenic assay. No tumour cell growth was observed in 5/5 independent experiments after 18 h of coculture with LAK. No significant inhibition of CFU-GM growth was also noted. Subsequently, the effect of LAK on BM obtained from four leukaemic patients and contaminated with 20-50% of their own AML and ALL cells was studied using MAb as a tool for identifying leukaemic cells. LAK eliminated 24-78% of contaminating cryopreserved uncultured autologous leukaemic cells. In five cases the BM was contaminated by a low (2%) amount of ALL cells. In these patients the monoclonal heavy chain rearrangement typical of ALL was no longer visible after coculture with LAK. Evidence for selective tumour cytotoxicity by LAK was confirmed by using autologous BM cells as hot and cold targets in a 51Cr release assay. Finally, successful haematologic reconstitution of lethally irradiated BALB/c mice was obtained using syngeneic BM cocultured with LAK. These results support the investigational use of rIL2 and LAK in the treatment of human leukaemia.

Acute Disease↗
PubMed1990

Response to intermediate and standard doses of IFN-beta in hairy-cell leukaemia.

Thirteen hairy-cell leukaemia patients were treated with IFN-beta (6 X 10(6) IU/m2) for 7 days, alternate weeks, for three cycles. IFN-beta was then continued at the same dose twice a week for 24 weeks. Treatment was discontinued in 2 non-responders and 2 partial responders (1 haem PR, 1 path PR) because of complications unrelated to IFN. The objective response in the nine patients who completed therapy was 66% (1 CR, 3 path PR and 2 haem PR); 2 patients achieved MR. Responses lasted from 5 to 45+ months. Four newly diagnosed patients and 3 in relapse after discontinuation of IFN-beta therapy (6 X 10(6) IU/m2), were treated with a lower dose of IFN-beta (2 X 10(6) IU/m2). The objective response to this dose was 57% (3 path PR, 1 haem PR). Another patient obtained MR. No patient has relapsed 6-12 months after therapy discontinuation. IFN-beta was well tolerated, especially at the lower dose and no chronic toxicity was observed. Therefore IFN-beta may be suggested as an alternative treatment for HCL.

Adult↗
PubMed1989

Characterization of cytoplasmic and nuclear polypeptides induced by interferon-gamma in a murine pre-B cell leukemia.

The effects of interferon-gamma (IFN-gamma) on protein synthesis of a pre-B cell leukemia, L1210, have been studied by two-dimensional gel electrophoresis. In total cell extracts, at least ten proteins were induced de novo, or increased in their expression, after an 18-h IFN-gamma treatment, whereas in the nuclear extracts eight proteins were specifically induced. Of these, increased synthesis of a 40-kDa/pI 5.9 cytoplasmic protein was the most prominent and reproducible. Most of these proteins appear to be specific for a defined step of differentiation, since they are not found in other B cell leukemias upon IFN-gamma treatment. Others appear to be tissue specific, since they are not induced in fibroblasts nor in T cells. In addition, synthesis of some of the induced proteins appeared to require rapid transcription of new mRNA, because actinomycin D markedly inhibited their formation when added immediately before IFN-gamma. In keeping with this finding, in vitro translation of mRNA from IFN-gamma-treated L1210 cells into a rabbit reticulocyte lysate system, followed by analysis of the labeled proteins by two-dimensional gel electrophoresis, revealed the appearance of at least seven proteins. Taken as a whole, these results demonstrate that in leukemic pre-B cells IFN-gamma induces the transcriptional activation of genes coding for cytoplasmic and nuclear proteins, some of which could be employed as specific cell activation markers.

Animals↗
PubMed1989

Modulation of NK activity by thymic hormones: in vitro effects of thymostimulin.

Plastic-adherent depleted or not depleted peripheral mononuclear blood cells (PMBC) from healthy donors showed enhanced lytic activity against 51Cr-labelled K562 target cells when exposed to thymostimulin (TS), 1 microgram ml-1, for 3 h, washed and incubated in TS-free medium before testing for natural killer (NK) cytotoxicity. No modification of NK cell activity was seen when effector cells were treated with placebo (splenic extract). The NK boosting activity of TS was lost when effector cells were treated for 3 h immediately before the performance of the cytotoxic test or when this thymic extract was added directly to the mixture of effector and target cells during the lytic phase of 51Cr release assay.

Cell Survival↗
PubMed1989

A phase I study of human natural interferon-beta in cancer patients.

In this phase I study 15 patients with metastatic tumors were given interferon (IFN)-beta by i.v. bolus injections. Twelve individual doses of 1, 2, 3.3, 5, 7, 9, 12, 16, 21, 27, 35, and 46 x 10(6) IU were administered every other day. The single maximal tolerated dose ranged from 9 to 46 x 10(6) IU. Eight patients tolerated the dose of 46 x 10(6) IU without side effects. Disturbances of cardiac rhythm were observed, but were closely related temporally to severe chills and appeared to be the consequence of adrenergic stimulation associated with this side-effect. In addition, no significant variations in the left ventricular function as assessed by nuclear stethoscope were observed. Neurotoxicity was not a major side-effect. The toxicity of IFN-beta given as scheduled in this study was significant, but acceptable.

Adult↗
PubMed1988

A randomized trial to evaluate the immunorestorative properties of thymostimulin in patients with Hodgkin's disease in complete remission.

A total of 19 Hodgkin's disease (HD) patients (12 male, 7 female) aged 26-67 years, who had been in complete unmaintained remission for 6 months or more when the study was initiated, were randomly given 50 mg thymostimulin (TS) i.m. daily (G1) or every other day (G2) for 35 days. A third group (G3) was not treated. Then TS, at the same dose was administered twice a week for the following 22 weeks in patients both initially receiving loading or intermittent TS treatment. When compared with age- and sex-matched controls, as a group, the patients' circulating OKT3+, OKT4+, OKT11+ and E-AETR+ cells were depressed (P less than 0.001 for both proportions and absolute numbers), whereas their OKT8+ cell population was not. Following 5 weeks of daily TS administration, the proportions and numbers of all T cell fractions significantly increased in G1 patients (P less than 0.03 for all the comparisons tested), while following intermittent TS treatment (G2) only the proportions of OKT3+ and OKT11+ cells (P less than 0.03), but not of other T cell fractions, significantly increased. In addition, no significant changes in the absolute numbers of T cell fractions were observed in this group of patients. Furthermore, no spontaneous variations in the T cell pool size occurred in untreated patients. TS maintenance therapy did not produce any further improvement in the size of overall T cells and T cell subsets but sustained percentage and absolute numbers of these cells during administration and the absolute number of T cells even after discontinuation of therapy. The TS-induced improvement in the T cell pool was not associated with any change in the size of circulating non-T lymphocytes and monocytes. In vitro phytohemagglutinin-induced interleukin-2 (IL-2) and gamma-interferon (IFN-gamma) synthesis was assessed in 11 patients (3 G1, 4 G2, and 4 G3). Although it was not statistically significant, a rise in IL-2 and IFN-gamma production was observed in TS-treated patients, but not in untreated controls. TS failed to exert any effect on the serum circulating levels of neopterin, type I and II IFN, beta-2 microglobulin (B2-M) and immunoglobulins (Ig). TS can thus improve defective T cell frequences and numbers and may modulate IL-2 and IFN-gamma production.

Adjuvants, Immunologic↗
PubMed1988

Biochemical host response to interferon-beta.

To assess influence of host response to interferon-beta (IFN-beta), on biochemical parameters, beta 2-microglobulin (beta 2-M) and neopterin were evaluated in 15 and 12 patients respectively before and 24 h after 1-46 X 10(6) IU intravenously (i.v.) IFN-beta given every other day. In 4 additional patients, both molecules were determined before and after 24, 48, 72, and 96 h of weekly IFN-beta injections. Serum beta2-M levels significantly increased 24 h after IFN-beta administration in the overall group of 15 patients treated with the alternate day schedule (p = 0.003) as well as in the group of patients treated with the weekly schedule (p = 0.00003). Maximum induction of beta 2-M was observed 24 h after a single weekly IFN-beta injection, but the levels of this protein 72 h after still remained significantly higher than baseline values (p = 0.001). This demonstrates the progressive accumulation of beta 2-M in the circulation produced by the continuous IFN administration. Nevertheless, in patients treated with both IFN treatment schedules, a clear correlation between the increments of beta 2-M and the IFN-beta doses was observed (p = 0.00002 and p = 0.0016 for the alternate day and the weekly schedule respectively). Furthermore the under curve area (AUC) of 48 h beta 2-M levels after IFN administration significantly rose (p less than 0.05) with increasing IFN doses in 4/6 patients. In spite of the accumulation of beta 2-M in the circulation, the overall serum values of this protein 24 h after each successive IFN-injection, in the 15 patients receiving the alternate-day treatment, were significantly higher than before the immediate preceding dose both in patients with initially normal and those with initially high base levels (p = 0.00055 and p = 0.011, respectively). As with beta 2-M, neopterin levels significantly rose during IFN treatment (p less than 0.05) in the group of patients as a whole. After single weekly IFN-beta injections, maximum induction of neopterin was observed 24 h after administration, then the levels of this molecule slowly declined towards the baseline levels, but 96 h after, its levels were still significantly elevated (p less than 0.00001). Neopterin induction was not related to IFN-beta doses, but the levels of this molecule both before and after IFN administration were correlated with an increase in the number of IFN injections (p = 0.0006 and p = 0.0009, respectively).(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗
PubMed1987

Immunologic profile in patients with Hodgkin's disease in complete remission.

Mononuclear cell subsets in peripheral blood, in vitro production of interleukin-2 (IL-2) and gamma interferon (IFN gamma), spontaneous cell-mediated cytotoxicity (SCMC) and circulating levels of Type I IFN, neopterin, beta-2 microglobulin (B2-M), immunoglobulins and complement fractions were studied in 33 patients with Hodgkin's disease (HD) in complete remission. The mean percentages, but not the absolute numbers, of T-lymphocytes expressing pan-T markers (OKT11, OKT3, ER, E-AET R) were significantly decreased compared with control values. Furthermore, patients showed a selective loss of OKT4+ cells, as well as increased percentages and numbers of Leu7+ and OKIa+ lymphocytes, and of OKM1+, LeuM2+, and LeuM3+ cells. OKT4+ cell depletion was a characteristic of patients with shorter time since beginning of remission as well as of those with nodular sclerosis (NS), mixed cellularity Hodgkin's disease (MC-HD), and systemic symptoms at diagnosis. Multifactorial statistical analysis carried out to investigate the effect of disease characteristics and the time since remission began on peripheral mononuclear blood cell (PMBC) subsets showed that histologic condition was the single best predictor of T-cell pool or OKT4+ cell subset size. Time since remission duration and other disease-related factors determined differences in the percentages, but not in the absolute numbers, of T-cell fractions. In addition, neither the disease features nor the time since remission duration determined significant differences in the absolute number of non-T-mononuclear cells in the various patient groups. Patients displayed decreased in vitro synthesis of IL-2 and IFN gamma. The values of SCMC, Type I IFN, neopterin, B2-M, immunoglobulins, and complement fractions did not differ greatly from those of controls.

Adult↗
PubMedDate not supplied

Allogeneic hemopoietic stem cell transplantation in solid tumors.

The existence of a graft versus tumor (GVT) effect of donor-derived T cells after allogeneic hematopoietic stem cell transplantation is well established as a critical component for the success of the procedure in several hematologic malignancies. Although it has been suggested that a GVT effect might also be generated in patients affected by refractory solid tumors, the morbidity of conventional allogeneic hematopoietic stem cell transplantation has limited its investigation in these diseases. Recently introduced allogeneic nonmyeloablative regimens have greatly decreased morbidity and mortality related to transplants which retain a powerful GVT. On this basis, it has become possible to explore the existence of alloreactivity toward solid tumors. The present article reviews the early clinical results of this novel immunotherapeutic approach for solid tumors.

Carcinoma, Renal Cell↗
PubMedDate not supplied

Different mechanisms regulate the IFN-inducible expression of 40 kDa human 2'-5' oligo (A) synthetase in HeLa and Molt 4 cells.

Expression of 40 kDa 2'-5' oligo (A) synthetase can serve as a marker of interferon (IFN) activity on the biological target. The mechanisms of induction of human 40 kDa 2'-5' oligo (A) synthetase by IFNs were investigated in HeLa and Molt 4 cells. Using a combined treatment with cycloheximide and actinomycin D we observed that in HeLa cells IFN-alpha did not need ongoing protein synthesis to induce the enzyme, whereas the addition of cycloheximide prevented the induction by IFN-gamma. IFN-alpha induced the 40 kD enzyme in the T-cell line Molt 4 to a level comparable to that in HeLa cells, but only in the presence of active protein synthesis. These results suggest that an early response gene coding for a positive IFN-inducible protein may be needed in T cells, but not in HeLa cells to regulate the transcription of this 2'-5' oligo (A) synthetase gene.

2',5'-Oligoadenylate Synthetase↗