Development of a multigenic plasmid vector for HCV DNA immunization

HCV viral nucleocapsid protein (C), non-structural protein 3 (NS3) and the envelope glycoproteins E1 and E2 are candidate immune targets for developing anti-HCV DNA vaccine. Nevertheless, the immune response elicited by these antigens often appears weak and/or transient. Different approaches have been studied for enhancing and/or modulating the immune response of the DNA vaccine. On the basis of a prototype multigenic plasmid vector constituted of two different transcription cassettes (pRC100), we have developed a plasmid vector that allows the independent and simultaneous expression of murine IL2 and of an antigenic domain of the HCV NS3 C terminus (pRC112-HCV). The highly conserved NS3 region spans from nt 4403 to nt 4829 and contains two putative B and T epitopes. The development of this multigenic plasmid vector may combine the expression and local production of an immunomodulatory molecule (mIL2) together with the possibility of addressing the host immune response to the most immunogenic and conserved epitopes, specifically tailored in the plasmid vector.

Promoting health: perspectives from ethnic elderly women

The purpose of this study was to investigate health-promoting measures used by ethnic elderly women. Within the context of this goal, two major research questions were asked: (a) What measures were used by the ethnic elderly women to promote their health? (b) What were the facilitators and barriers with respect to health promotion in this sample? A convenient and purposive sample consisted of 30 elderly women from three ethnic backgrounds--African American, Chinese American, and European American--who reside in an urban area of the northeastern part of the United States. Data were collected through in-depth interviews and survey questionnaires. Content and statistical analyses were employed. Participants identified measures, facilitators, and barriers in relation to promoting their health. These findings provide insight for community health nursing practice.

Effect of liposome-encapsulated alpha- or beta-interferon on breast cancer cell lines

Experimental evidence and clinical studies have indicated that interferons (IFN) inhibit proliferation in a wide panel of neoplasms, including breast cancer. However, the antitumor activity of IFN requires the continuous presence of high concentrations of the drug and is associated with side effects. To explore the potential of liposomes as an IFN delivery system, we compared the effect of free or liposome-encapsulated alpha-IFN and beta-IFN on the growth of two breast cancer cell lines (MCF7 and MDA-MB231). Cells were cultured in the presence of IFN at different concentrations (500, 1000, 2000 IU/ml) or in the presence of multilamellar liposomes (phosphatidylcholine-phosphatidylserine at a molar ratio of 7:3) containing saline buffer, alpha-IFN or beta-IFN. Additional control groups consisted of cells cultured with alpha-IFN or beta-IFN plus empty liposomes. Empty liposomes were not cytotoxic and did not interfere with IFN activity. In both cell lines liposomes encapsulating alpha-IFN (at the highest lipid:drug ratio) inhibited cell growth in a manner similar to that of free alpha-IFN, whereas liposomes encapsulating beta-IFN showed slightly, lower inhibition than free beta-IFN, this was more evident in MCF7 cells. The present results indicate that liposomes encapsulating alpha-IFN or beta-IFN were effective on the growth of both breast cancer cell lines, which are characterized by a different estrogen responsiveness, and that they might be a useful carrier system for the delivery of high doses of IFN.

A novel chromosomal translocation t(4; 14)(p16.3; q32) in multiple myeloma involves the fibroblast growth-factor receptor 3 gene

Chromosomal translocations involving the immunoglobulin heavy chain (IGH) locus at chromosome 14q32 represent a common mechanism of oncogene activation in lymphoid malignancies. In multiple myeloma (MM), the most consistent chromosomal abnormality is the 14q+ marker, which originates in one third of cases through a t(11; 14)(q13; q32) chromosomal translocation; in the remaining cases, the identity of the partner chromosomes has not been well established. We used a Southern blot approach based on the linkage analysis of the joining (J) and the constant (C) mu, alpha, and gamma regions to detect cases bearing IGH switch-mediated chromosomal translocations. We evaluated DNA of 88 nonkaryotyped patients with MM (78 cases) or plasma cell leukemia (PCL) (10 cases) and found the presence of "illegitimate" rearranged IGH fragments (no comigration between the J and C regions) in 21 cases. To confirm this analysis, we cloned the illegitimate rearranged fragments from three samples, and the molecular and fluorescent in situ hybridization (FISH) analyses indicated the presence of chromosomal translocations juxtaposing a switch IGH region to sequences from chromosomes 11q13 (one PCL case) or 4p16.3 (two MM cases). Interestingly, the breakpoints on 4p16.3 occurred about 14 kb apart in a genomic region located approximately 50 kb centromeric to the fibroblast growth-factor receptor 3 (FGFR3) gene. Moreover, Southern blot analysis using 4p16.3 genomic probes detected a rearrangement in an additional MM tumor. FISH analysis of the MM-derived KMS-11 cell line, reported to be associated with a t(4; 14)(p16.3; q32), showed that the FGFR3 gene was translocated on 14q32. High levels of FGFR3 mRNA expression were observed in the cloned MM tumors and KMS-11 cell line, but not in the cases that were apparently negative for this lesion. Furthermore, a point mutation at codon 373 in the transmembrane domain of the FGFR3 gene resulting in an amino acid substitution (Tyr --> Cys) was detected in the KMS-11 cell line. These findings indicate that the t(4; 14)(p16.3; q32) represents a novel, recurrent chromosomal translocation in MM, and suggest that the FGFR3 gene may be the target of this abnormality and thus contribute to tumorigenesis in MM.

Langerhans cell histiocytosis arising after Hodgkin's disease

We present the case of a 19-year-old male who suffered from Langerhans cell histiocytosis (LCH) 12 months after having been treated for recurrent Hodgkin's disease (HD). Immunophenotypic characterization and electron microscopic analysis were useful for the exclusion of a bone relapse of Hodgkin's disease or any other differential diagnosis. The association of LCH with HD or other malignancies is rare but more frequent than previously believed. The significance of such an association and the pathophysiology of LCH are still open questions.

Influence of autonomic tone on QT interval duration

The autonomic tone has been shown to influence the duration of the QT interval, however the independent contribution of sympathetic and parasympathetic tone is not fully elucidated. The influence of autonomic tone on QT duration was studied in 10 young healthy volunteers by evaluating the changes in QT and RR duration induced by i.v. isoproterenol infusion and by standing before and after i.v. administration of propranolol or atropine. Furthermore, the relationship between RR interval and QT duration was evaluated during nocturnal sinus arrhythmia and submaximal exercise test. Low doses of isoproterenol reduced RR (p < 0.01) but not QT interval duration, while higher doses influenced both RR (p < 0.0001) and QT (p < 0.001) duration. Propranolol did not influence standing-induced shortening of RR and QT intervals; on the contrary, atropine administration abolished standing-induced QT interval shortening, without influencing RR changes. QT duration resulted significantly related to preceding RR interval at peak exercise (r = 0.87, p < 0.001) and during nocturnal sinus arrhythmia (r = 0.73, p < 0.0005), however, the regression lines showing the correlation between QT and preceding RR interval were different. Both sympathetic and parasympathetic tone appear to contribute to heart rate-independent changes in QT duration. In the basal state parasympathetic more than sympathetic tone influences the relation QT-heart rate. Major increases of sympathetic nervous system activity may change the relation QT-heart rate. Thus, in case of abrupt autonomic changes, any proposed formula for heart rate correction of QT may result inappropriate, also in the normal range of heart rate.

Genetic modification of a carcinoma with the IL-4 gene increases the influx of dendritic cells relative to other cytokines

Tumor cells genetically modified with certain cytokine genes gain immunogenic properties that allow the development of systemic anti-tumor immunity. Whether different cytokines may influence infiltration of transduced tumors by dendritic cells (DC) has not been investigated. Therefore, we analyzed the C26 murine colon carcinoma genetically modified to release interleukin (IL)-2, IL-4, IL-12, granulocyte colony-stimulating-factor (CSF) or granulocyte-macrophage (GM)-CSF for immunostaining with the monoclonal antibody NDLC145 recognizing the DEC205 determinant which, on tumor sections, is virtually restricted to DC. Infiltrating leukocytes were also characterized for expression of co-stimulatory molecules like CD54, CD86 and major histocompatibility complex class II. The intratumoral DC content was dependent on the type of transduced cytokines with C26/IL-4 being the most abundant in DEC205+ cells. The effect of IL-4 in recruiting DC did not depend on the type of tumor since it was confirmed in the TSA mammary carcinoma. In comparison with C26/GM-CSF, C26/IL-4 had more B7.2+ cells but less Ia+ cells. Furthermore, the hypertrophic skin overlaying tumors producing GM-CSF showed numerous Langerhans cells stained by NDLC145 and the draining lymph nodes showed abundance and paucity of DC in C26/GM-CSF and C26/IL-4, respectively. When injected into the ear pinna, C26/GM-CSF stimulated, whereas C26/IL-4 inhibited DC-mediated priming of delayed-type hypersensitivity reaction by 2,4-dinitro-1-fluorobenzene. These findings prove that transduced cytokines differently influence DC recruitment at the tumor site and DC function in nearby tissues. Along with the other leukocytes and their secondary produced cytokines, DC create an environment in which T cells can be differently modulated. Such a phenomenon may have implications on genetic modification of tumor cells to be used as cancer vaccine.

Constitutive expression of lymphoma-associated NFKB-2/Lyt-10 proteins is tumorigenic in murine fibroblasts

The NFKB-2 (Lyt-10) gene codes for an NF-kappaB-related transcription factor containing rel-polyG-ankyrin domains. Rearrangements of the NFKB-2 locus leading to the production of 3' truncated NFKB-2 proteins are recurrently found in lymphoid neoplasms, particularly cutaneous lymphomas. Such mutant NFKB-2 proteins have lost the ability to repress transcription that is typical of NFKB-2 subunit p52, and function as constitutive transcriptional activators. To verify whether the expression of abnormal NFKB-2 proteins can lead to malignant transformations in mammalian cells, we transfected human lymphoblastoid cell lines and murine fibroblasts (Balb/3T3) with expression vectors carrying the cDNAs coding for normal NFKB-2p52, Lyt-10C alpha or LB40 proteins, which are representative of the abnormal types found in lymphoma cases. The expression of both normal and mutant NFKB-2 proteins has a lethal effect on lymphoblastoid cells and a cytotoxic effect was also observed in murine fibroblasts. The fibroblast cell lines expressing Lyt-10C alpha or LB40, but not those expressing normal NFKB-2p52, were capable of forming colonies in soft agar. The analysis of individual clones revealed that cloning efficiency correlated with the expression levels of the abnormal proteins. Injection of the Lyt-10C alpha-transfected Balb cells in SCID mice led to tumor formation in all of the animals, whereas no tumors were observed in the mice injected with control or NFKB-2p52-transfected cells, thus indicating that abnormal NFKB-2 protein expression is tumorigenic in vivo. Our results show that mutant NFKB-2 proteins can lead to the transformed phenotype, and support the hypothesis that alterations in NFKB-2 genes may play a role in lymphomagenesis.

Internalization of Aspergillus fumigatus conidia by epithelial and endothelial cells

The internalization of conidia of the opportunistic fungus Aspergillus fumigatus by primary cell cultures of nonprofessional phagocytes was investigated. This study is the first to show that A. fumigatus conidia were able to be engulfed by tracheal epithelial, alveolar type II, and endothelial cells.

Immunocytochemical and immunoelectron microscopical analysis of BCL2 expression in thyroid oxyphilic tumors

In both human lymphoma and carcinoma, BCL2 expression contributes to the neoplastic development by preventing normal turnover due to programmed cell death. In thyroid carcinoma it was shown that BCL2 expression is related to cell differentiation and appears to be associated with a less aggressive behavior. Using immunogold electron microscopy labeling techniques on ultrathin frozen sections, the authors undertook an analysis of bcl-2 protein localization in 7 cases of thyroid tumor with (4 cases) or without (3 cases) oncocytic differentiation, which displayed histopathological features, corresponding to different degree of aggressiveness. All thyroid tumors and a lymphoblastoid cell line overexpressing BCL2 showed a preferential labeling of mitochondrial circumference, while the 4 cases with oncocytic differentiation displayed a bcl-2 protein location, not only on the circumference but also on the cristae of a consistent number of mitochondria. These results may indicate a bcl-2 protein interaction with intramitochondrial constituents related to the neoplastic transformation in oncocytic tumor.

Development of an in vitro macrophage system to assess Penicillium marneffei growth and susceptibility to nitric oxide

We investigated the effect of nitric oxide (NO) and reactive nitrogen intermediates on the in vitro growth of Penicillium marneffei both in a cell-free system and in a novel macrophage culture system. In the cell-free system, NO that was chemically generated from NaNO2 in acid media (pH 4 and 5) markedly inhibited the growth of P. marneffei. On the contrary, inhibition of growth did not occur in neutral medium (pH 7.4) in which NO was not produced. P. marneffei conidia were phagocytized by nonstimulated murine J774 macrophages after 2 h of incubation. During the following 24 h, P. marneffei grew as yeast-like cells replicating by fission in the J774 macrophages. The intracellular growth of P. marneffei damaged nonstimulated J774 macrophages, as confirmed by electron microscopy. When J774 cells were stimulated by gamma interferon and lipopolysaccharide, which led to enhanced production of reactive nitrogen intermediates, the percentage of yeast-like cells was significantly reduced and P. marneffei conidia were damaged in the J774 macrophages. The inhibition of NO synthesis by N-monomethyl-L-arginine restored the intracellular growth of P. marneffei. The inverse correlation between intramacrophage growth and the amount of nitrite detected in culture supernatants supports the hypothesis that the L-arginine-dependent NO pathway plays an important role in the murine macrophage immune response against P. marneffei.

The involvement of the candidate proto-oncogene NFKB2/lyt-10 in lymphoid malignancies

NF-kappa B transcription factors regulate the expression of a variety of genes involved in immune responses and cell growth. In higher vertebrates, the NF-kappa B family encompasses five distinct members. Three NF-kappa B proteins, p65/RelA, RelB, and c-rel/Rel, have high transactivating potential in addition to their DNA binding activity. Two subunits, NF-kappa B1p50 and NF-kappa B2p52, coded respectively by the NFKB1 and NFKB2 genes, may only have DNA binding activity. Moreover, p50 and p52 subunits are translated as precursors, respectively p105 and p100, which can be processed into the mature active forms by the removal of their carboxy-terminal ankyrin domain. The five proteins share a homologous amino-terminal domain (rel domain) involved in DNA binding, dimerization, nuclear transport, and binding of regulatory subunits. All members form homo- and heterodimeric complexes with different DNA binding specificity and transactivating potential. Structural alterations of some members of the NF-kappa B gene family have been observed in lymphoid malignancies. In particular, the NFKB2 gene, localized on chromosome 10q24, represents a candidate proto-oncogene, since it has been found rearranged in certain types of lymphoma and more commonly in cutaneous lymphoma. Molecular analysis indicated that these rearrangements may occur as a consequence of chromosomal translocations or small internal chromosomal deletions. Rearrangements cluster within the carboxy-terminal ankyrin domain of the NFKB2 gene leading to the production of carboxy-terminally truncated proteins which, in some cases, are fused to heterologous protein domains. Experimental data showed that these abnormal proteins are constitutively localized in the nucleus, have lost the transcriptional repressor functions typical of normal NF-kappa B2p52 and may be capable of transactivation activity. These findings suggest that abnormal NFKB2 proteins may contribute to lymphomagenesis by altering the NF-kappa B system, both quantitatively and qualitatively, and leading to the activation of specific subsets of kappa B-controlled genes.

Expression of A-myb, but not c-myb and B-myb, is restricted to Burkitt's lymphoma, sIg+ B-acute lymphoblastic leukemia, and a subset of chronic lymphocytic leukemias

The A-myb gene encodes a transcription factor that is related both functionally and structurally to the v-myb oncogene. Following our observations that A-myb is expressed in a restricted subset of normal mature human B lymphocytes, with the phenotype CD38+, CD39-, slgM-, we have now investigated the pattern of A-myb expression in neoplastic B cells representating the whole spectrum of B-cell differentiation and compared it to that of c-myb and B-myb. In a panel of 32 B-cell lines, A-myb was very strongly expressed in most Burkitt's lymphoma (BL) cell lines, but weak or negative in 2 pre-B acute lymphoblastic leukemia (ALL), 4 non-Hodgkin's lymphoma (NHL), 6 Epstein-Barr virus-immortalized lymphoblastoid cell lines, and 6 myeloma lines. Protein expression paralleled that of the RNA. We have also investigated A-myb expression in 49 fresh cases of B leukemias. Among 24 ALL, 6 were of the null and 11 of the common type and all these were negative for A-myb expression; on the other hand, all 7 B-ALL cases (slg+), as well as one fresh BL case with bone marrow infiltration, expressed A-myb. A-myb was undetectable in 4 prolymphocytic leukemias (PLL) but was strongly expressed in 5/20 (25%) of chronic lymphocytic leukemia (CLL) samples. In the latter A-myb did not correlate with phenotype or clinical stage. Finally, we have studied the progression of one case of CLL into Richter's syndrome and have found that the Richter's cells expressed about 25-fold less A-myb RNA than the CLL cells from the same patient. The pattern of c-myb and B-myb was clearly distinct from that of A-myb. C-myb and B-myb were expressed in all neoplastic groups, except in CLL cells. Thus, A-myb expression, unlike that of c-myb and B-myb, is restricted to a subset of B-cell neoplasias (in particular BL and slg+B-ALL) representative of a specific stage of B-cell differentiation. This expression may in part reflect expression of A-myb by the normal germinal center B cells that are the normal counterpart of these transformed B cells. The data presented strongly support a role for this transcription factor in B-cell differentiation and perhaps in B-cell transformation in some neoplasias.

Hypoxic tumor cell death and modulation of endothelial adhesion molecules in the regression of granulocyte colony-stimulating factor-transduced tumors

C-26 colon adenocarcinoma cells transduced with the granulocyte colony-stimulating factor (G-CSF) gene form large tumors when injected into sublethally irradiated mice. These tumors regress when leukocyte function is reconstituted. Electron microscopy and immunocytochemical analysis of regressing C-26/G-CSF nodules indicates that tumor destruction is due mainly to hypoxia resulting from the functional loss of tumor vasculature and is only marginally due to direct cytolysis. Desegregation of basal lamina, cell swelling, and loss of junctions characterized the vessels within regressing tumors. Tumor cells were necrotic or filled with lipid vacuoles regardless of the distance from nearby vessels. Damage of tumor vasculature was dependent on the infiltrating leukocytes and the cytotoxic cytokines they produced. Locally produced interleukin-1 and tumor necrosis factor-alpha (TNF-alpha) induced vascular cellular adhesion molecule-1 (VCAM-1) and E-selectin on tumor vessels. Treatment with monoclonal antibodies to interferon-gamma (IFN-gamma) or TNF-alpha blocked tumor regression by inhibiting VCAM-1 and E-selectin expression on tumor-associated endothelial cells resulting in a reduced number of infiltrating leukocytes. Thus, C-26/G-CSF tumor regression presents features typical of hemorrhagic necrosis that occurs through the cytokines produced by infiltrating leukocytes in response to G-CSF.

Macrophage infiltrate and prognosis in c-erbB-2-overexpressing breast carcinomas

PURPOSE

Experiments were designed to investigate the association between tumor leukocytic infiltrates with other pathologic and biologic variables in primary tumors and with prognosis, and to define the phenotype of the infiltrating leukocytes.

PATIENTS AND METHODS

A retrospective series of 1,207 primary breast carcinomas was studied according to different prognostic variables, including the presence of lymphoplasmacytic infiltrate (LPI). LPI was analyzed in association with other variables and survival. Additionally, a small prospective series of surgical specimens from 75 primary breast carcinomas with infiltrating leukocytes was tested by immunohistochemistry on frozen sections to phenotypically characterize the infiltrate, using anti-CD reagents, and the tumor, using anti-c-erbB-2 oncoprotein monoclonal antibody.

RESULTS

In the retrospective series, menopausal status, nodal status, tumor size, stage, grade, and p185HER2 overexpression but not LPI were found to be associated with prognosis and maintained their prognostic significance in a multivariate analysis. LPI was significantly associated with some of these independent prognostic factors, such as tumor size (P = .03), stage (P = .004), grade III carcinomas (P < .000001), and overexpression of the p185HER2 (P < .000001). In some subgroups of patients in whom LPI was found more frequently, such as grade III cases or N- and c-erbB-2-positive cases, LPI was found to be indicative of a good prognosis (P = .008 and P = .03, respectively). Phenotypic analysis of the infiltrating leukocytes revealed a preponderance of macrophages in high-grade (P = .05) or c-erbB-2-positive (P = .008) tumors, whereas T cells constituted most of the infiltrate in the other tumors.

CONCLUSION

Our data demonstrate different leukocytic types in the infiltrate of breast tumors with different prognostic significance.

Massive ex vivo generation of functional dendritic cells from mobilized CD34+ blood progenitors for anticancer therapy

We report that blood cell autografts, collected by single leukapheresis in cancer patients (n = 11) at the time of mobilization of hematopoietic progenitors into peripheral blood following anticancer therapy with high-dose cyclophosphamide (HD-CTX) plus interleukin-3 (IL-3) and granulocyte colony-stimulating factor (G-CSF/filgrastim), comprise 1.98 +/- 0.39 x 10(5)/kg (mean +/- SE) CD34+ progenitors of dendritic cells (DCs). This number corresponds to 140-fold more progenitors than in a control autograft collected in the steady state. DCs derived from mobilized CD34+ cells, morphologically and immunophenotypically undistinguishable from skin Langerhans cells and DCs from bone marrow and cord blood CD34+ cells, are shown to be powerful stimulators of allogeneic T cell proliferation in primary MLR and of autologous HLA-DR-restricted CD4+ T cell proliferation in response to presentation of xenogenic antigens. We show that the GM-CSF-plus-TNF-alpha-dependent ex vivo generation of DCs from mobilized CD34+ cells is 2.5-fold enhanced by flk-2/flt-3 ligand or c-kit ligand (stem cell factor) and five-fold enhanced by a combination of these growth factors. In addition, the optimal serum for the generation of DCs is autologous HD-CTX recovery-phase serum rather than fetal calf serum (FCS) or steady-state human serum, which are clinically inadequate and ineffective, respectively. In practice, the stimulation of CD34+ cells in a blood cell autograft (15.75 +/- 2.46 x 10(6)/kg) provided by the above four growth factors should permit ex vivo generation of approximately 40 x 10(9) DCs in an adult patient. These new findings provide advantageous tools for the large-scale generation of DCs that are potentially usable for clinical protocols of immunotherapy or vaccination in patients undergoing cancer treatment.

Rearranged NFKB-2 genes in lymphoid neoplasms code for constitutively active nuclear transactivators

The NFKB-2 gene codes for an NF-kappa B-related transcription factor containing rel-polyG-ankyrin domains. Chromosomal rearrangements of the NFKB-2 locus have been found in various types of lymphoid neoplasms, suggesting that they may contribute to lymphomagenesis. Rearrangements cluster within the 3'-terminal ankyrin-encoding domain of the NFKB-2 gene and lead to the production of C-terminally truncated proteins which, in some cases, are fused to heterologous protein domains. In order to determine the functional consequences of these alterations, we have analyzed the subcellular localization, DNA binding, and transcriptional activity of two representative tumor-associated mutants in which the ankyrin domain is either terminally truncated (NFKB-2p85) or truncated and joined to an out-of-frame immunoglobulin C alpha domain (lyt-10C alpha). Immunofluorescence studies performed on cells transfected with p85 or lyt-10C alpha expression vectors showed that both the abnormal proteins were constitutively localized in the nucleus. Immunoprecipitation analysis of UV-cross-linked DNA-protein adducts showed that p85 can bind kappa B sites in its unprocessed form. Cotransfection of p85 or lyt-10C alpha expression vectors with kappa B-driven reporter plasmids showed that both p85 and lyt-10C alpha have retained the ability to mediate transcriptional activation via heterodimerization with Rel-Ap65 but have lost the transrepression activity associated with homodimeric DNA binding. Furthermore, both p85 and lyt-10C alpha were capable of independent transactivation of kappa B-reporter genes and this activity could not be further stimulated by Bcl-3. These abnormal proteins may contribute to lumphomagenesis by determining a constitutive activation of the NF-kappa B system and, in particular, of NFKB-2 target genes.

[A case of gastric hemangiopericytoma]

The authors report a case of gastric hemangiopericytoma. This tumor, histogenetically derived from pericytes, has been detected in any tissue or structure. According to the review of the literature, the hemangiopericytoma of the stomach occurred very uncommonly, being published only 29 cases. Diagnosis is based on histological and immunohistochemical techniques. Surgery is the main therapy but the impredictable biological behaviour require different strategies.

Structural and functional characterization of the promoter regions of the NFKB2 gene

In order to clarify the transcriptional regulation of the NFKB2 gene (lyt-10, NF-kappa Bp100), we have characterized the structure and function of its promoter regions. Based on the nucleotide sequence of cDNA clones and the 5' flanking genomic region of the NFKB2 gene, RT-PCR analysis in a number of human cell lines demonstrated the presence of two alternative noncoding first exons (1a and 1b). Two distinct promoter regions, P1 and P2, were identified upstream of each exon, containing multiple sites of transcription initiation, as shown by RNase protection analysis. Sequence analysis of these regions showed a CAAT box upstream of exon 1a and high G-C content regions within both P1 and P2. Consensus binding sites for transcription factors, including SP1, AP1 and putative NF-kappa B (kappa B sites), were found upstream of each exon. In particular, six kappa B sites were identified, all but one of them capable of binding NF-kappa B complexes in vitro. Transfection in HeLa cells of plasmids containing P1 and P2 sequences linked to a chloramphenicol acetyltransferase reporter gene indicated that both P1 and P2 can act independently as promoters. Co-transfection of NF-kappa B effector plasmids (NF-kappa Bp52 and RelA) with a reporter gene linked to P1 and P2 showed that the NFKB2 promoter regions are regulated by NF-kappa B factors. RelA transactivates the NFKB2 promoter in a dose-dependent manner, whereas NF-kappa Bp52 acts as a repressor, indicating that the NFKB2 gene may be under the control of a negative feedback regulatory circuit.

Heterogeneous chromosomal aberrations generate 3' truncations of the NFKB2/lyt-10 gene in lymphoid malignancies

The NFKB2(lyt-10) gene codes for a protein that is a member of the NK-kappa B/rel family of transcription factors containing a DNA-binding rel domain and a carboxy-terminal ankyrin-like domain. The NFKB2 gene represents a candidate proto-oncogene, since it has been found to be involved in a chromosomal translocation t(10;14)(q24;q32) in one case of B-cell lymphoma and in gene rearrangements in various types of lymphoid malignancies. To elucidate the structural and functional consequences of NFKB2 rearrangements, we report the molecular characterization of three novel rearranged NFKB2 genes in lymphoid tumors. In one case of multiple myeloma (MM), cloning and sequencing analysis of reciprocal breakpoint sites showed that they occurred within intron 15 of the NFKB2 gene and led to the complete deletion of the 3' portion of the gene coding for the ankyrin domain. Fluorescent in situ hybridization (FISH) analysis showed that the novel regions involved in the NFKB2 rearrangement originated from chromosome 7q34, thus implying the occurrence of a t(7;10)(q34;q24) reciprocal chromosomal translocation. In one case of T-cell cutaneous lymphoma (CTCL) and in one of B-cell chronic lymphocytic leukemia (B-CLL), NFKB2 rearrangements occurred, respectively, within exons 18 and 20 of the gene and involved recombinations with distinct regions of chromosome 10q24. Molecular analysis suggested that these rearrangements may occur as a consequence of small internal chromosomal deletions. In both of these cases, the rearrangements led to specific carboxy-terminal truncations of NFKB2 generating abnormal transcripts that coded for proteins lacking portions of the ankyrin domain. These proteins localize in the nucleus, suggesting their constitutive activation in vivo. Overall, our results indicate that NFKB2 rearrangements in lymphoid neoplasia may occur by heterogeneous mechanisms, including internal chromosomal deletion or chromosomal translocation. The common consequence of these rearrangements appears to be the deletion of 3' sequences of NFKB2 leading to the production of carboxy-truncated constitutively nuclear proteins that may be involved in tumorigenesis.

Colocalization of the p185HER2 oncoprotein and integrin alpha 6 beta 4 in Calu-3 lung carcinoma cells

Anti-p185HER2 monoclonal antibodies often show intense reactivity with the basement membrane of tumor cells that overexpress the HER2/neu gene product (p185HER2). To evaluate a possible interaction between p185HER2 and adhesion molecules or their receptors, the polarity of p185HER2 was tested in lung carcinoma cell line Calu-3, which overexpresses this protein, in cultures grown as confluent monolayers or as aggregates. MAb immunostaining patterns indicated that p185HER2 is concentrated on the baso-lateral membrane of cells and that it colocalizes with the integrin alpha 6 beta 4 at the cell-cell junctions where laminin is also found. The same membrane region showed intense reactivity with antiphosphotyrosine antibodies. Furthermore, integrin clustering induced by the specific antibody was accompanied by the clustering of p185HER2, as indicated by immunoelectron microscopy, and by a subsequent increase in p185HER2 tyrosine phosphorylation. Treatment with exogenous laminin also resulted in increased basal levels of p185HER2 phosphorylation. These data suggest a physical interaction between the integrin and the oncoprotein that might be functionally relevant in directly controlling the tyrosine phosphorylation of the catalytic domain of p185HER2.

Rearranged NFKB2 gene in the HUT78 T-lymphoma cell line codes for a constitutively nuclear factor lacking transcriptional repressor functions

Rearrangements of the NFKB2 gene are associated with lymphoid malignancies, but the functional significance of these alterations is not known. Here we characterize structurally and functionally a rearranged NFKB2 gene identified at the T cell lymphoma line, HUT78. The rearrangement has truncated NFKB2 sequences within the 3' ankyrin domain, leading to the production of truncated mRNA species and proteins as detected by Northern blot and immunoprecipitation analysis, respectively. Cloning and sequencing of the corresponding cDNAs indicates that, via alternative splicing, the rearranged gene codes for two proteins of 84 and 85 kD (p84/85) which retain the DNA-binding rel domain and the first five ankyrin repeats, but have lost their carboxy-terminus including the seventh ankyrin repeat. Immunofluorescence and immunoprecipitation analysis of HUT78 cells indicate that p84/85 are abnormally located in the nucleus in an unprocessed form, suggesting that these proteins can escape the cytoplasmic retention typical of the normal NFKB2 p100 protein before it is processed into p52. Electrophoretic mobility shift assays performed on HUT78 nuclear extracts indicate that the abnormal NFKB2 proteins bind kappa B sites specifically and alter the composition of NF-kappa B complexes in HUT78 cells. Transient co-transfection assays involving NFKB2 expression vectors and kappa B-driven reporter plasmids indicate that NFKB2 p85 has lost the transcriptional repressor functions typical of normal NFKB2 p52. These data indicate that the NFKB2 gene rearrangement detected in HUT78 cells leads to the production of abnormal NFKB2 proteins capable of altering the function of the NF-kappa B transcription system. Since analogous rearrangements are found in lymphoid malignancies, these findings further support a role of NFKB2 alterations in tumorigenesis.

Mechanism of expression and role in transcriptional control of the proto-oncogene NFKB-2/LYT-10

The NFKB-2 gene (previously LYT-10, NF-kappa Bp100 or NF-kappa Bp97) codes for a NF-kappa B/rel related protein which is highly homologous to NFKB-1 (previously NF-kappa Bp105) within its rel, poly-glycine and ankyrin domains. The NFKB-2 gene is a candidate proto-oncogene since it is involved in lymphoma-associated chromosomal aberrations. In order to gain insight into the physiological function and role in tumorigenesis of NFKB-2, we have analysed its mechanism of expression and role in transcriptional regulation. We report that, contrary to previous studies, a single 3.2 kb mRNA species and its 100 kD (p100) primary translation product is detectable in all cell types tested. A second NFKB-2 protein, p52, corresponding to the amino-terminal half (rel domain) of NFKB-2 p100, is detectable in the same cell types and derives from the post-translational processing of p100. While p100 is constitutively localized in the cytoplasm, NF-kappa B induction by TPA treatment of Hela cells is associated with cytoplasmic/nuclear translocation of NFKB-2 p52 and its appearance within DNA-binding NF-kappa B complexes. NFKB-2 p52 differs from NFKB-1p50 in its differential affinity for kappa B sequences: by itself it binds H2/HLA-kappa B sites more efficiently than HIV/IgK-kappa B sites, while it can bind both sites efficiently when complexed with Rel-A(p65). Transient co-transfection of expression and reporter plasmids in cells devoid of endogenous NF-kappa B activity showed that p52 has no intrinsic transcriptional activation capabilities: it can stimulate Rel-A(p65)-driven transcription by formation of p65/p52 heterodimers, whereas, overexpressed, it down-regulates p65-dependent transcription by formation of inactive p52/p52 homodimers. These results indicate that the NFKB-2 gene codes for an inducible NF-kappa B transcription factor with the capability of differentially regulating NF-kappa B transcription depending on its abundance in the nucleus.

[Comparison of nisoldipine and diltiazem in the treatment of effort angina pectoris]

BACKGROUND

In order to evaluate the benefits of a calcium-antagonist medium-term treatment, 20 patients with effort stable angina pectoris were treated with nisoldipine in comparison to diltiazem.

METHODS

Twenty patients with stable effort angina completed a double-blind, placebo controlled trial, comparing 10 twice daily nisoldipine per os and diltiazem 120 three times daily per os for 28 days. After wash-out, placebo and drug period, ergometer stress tests were performed. Exercise tolerance, angina frequency, nitrate consumption and side effects were evaluated.

RESULTS

Our results showed that both drugs significantly increased exercise tolerance. Exercise duration was 330 +/- 107 sec after placebo, 397 +/- 106 sec after nisoldipine (p < 0.05) and 378 +/- 99 sec after diltiazem (p < 0.05). Effort angina episodes decreased from 20 after placebo to 8 after nisoldipine and diltiazem. Both drugs reduced rate-pressure product at submaximal exercise in comparison to placebo. There were no differences at peak exercise between placebo or drug periods. Both drugs similarly reduced nitrate consumption and weekly effort angina attacks. No patients referred serious side-effects.

CONCLUSIONS

nisoldipine, like diltiazem, is an effective drug in the treatment of stable effort angina. Moreover, the therapeutic effects of nisoldipine during medium-term treatment are probably related to decrease in oxygen consumption.