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C Fonatsch

Publications and source records attributed to C Fonatsch.

At least 109 records · Page 6Linked to original sources
PubMed1994

The Met/hepatocyte growth factor receptor (HGFR) gene is overexpressed in some cases of human leukemia and lymphoma.

The proto-oncogene c-met encodes a heterodimeric (alpha, beta) tyrosine kinase receptor which binds the hepatocyte growth factor (HGF). Recently, overexpression of the Met/HGF receptor gene has been detected in fresh samples of carcinomas and in epithelial tumor cell lines but not in cell lines derived from human leukemia and lymphoma. Our analysis of 50 primary samples of human leukemia and lymphoma and 23 hematopoietic cell lines revealed expression of mRNA and protein of the met/HGF receptor in 6 out of the 73 hematopoietic tumor samples analyzed. Four of the six samples positive for expression of the Met/HGF receptor gene were derived from patients with Hodgkin's disease. In addition, in one Burkitt's lymphoma cell line and in one acute myeloid leukemia (AML), expression of the Met/HGF receptor gene was detected. In normal unstimulated lymphocytes, granulocytes or monocytes we did not find expression of the Met/HGF receptor gene. Upon stimulation with the phorbol ester TPA we detected a weak expression of Met/HGF receptor specific transcripts of 9.0 kb in peripheral blood mononuclear cells of a healthy donor. Cytogenetic analyses of three of the four cell lines which express the Met/HGF receptor gene revealed structural or numerical abnormalities of the long arm of chromosome 7, where the Met/HGFR gene is located, in each of the three cell lines analyzed. In one of these cell lines (L540) the Met/HGFR gene is translocated to a marker chromosome. Southern blot and pulsed field gel electrophoresis experiments did not show any rearrangement in a region of 600 kb around the Met/HGF receptor gene excluding an activation of Met/HGFR by a TPR/Met oncogenic rearrangement as described for MNNG-HOS cells and for some gastric tumors. Our data indicate that the Met/HGFR gene is deregulated in a few cases of human leukemia, Burkitt's lymphoma and Hodgkin's disease possibly by chromosomal rearrangements resulting in an overexpression of the normal Met/HGF receptor mRNA and protein without formation of a hybrid gene.

Chromosome Aberrations↗
PubMed1994

Disseminated growth of Hodgkin's-derived cell lines L540 and L540cy in immune-deficient SCID mice.

Local tumor growth has been reported after subcutaneous and intraperitoneal injection of Hodgkin's disease (HD) derived cell lines into different immunodeficient mouse strains. An animal model with disseminated growth of tumor cells would be useful for studying the in vivo biology of HD cells as well as for preclinical testing of new therapeutic regimens. For this purpose the HD-derived cell lines L540, L540cy, L428, and KM-H2 were injected intravenously into SCID mice. In contrast to L428 and KM-H2, widespread neoplasia occurred after a period of four to six weeks following injection of L540 and the subline L540cy. Lymph nodes were found to be the preferred site of tumor growth. CD30 surface antigen expression on Hodgkin cells and the karyotype of the tumor cells were preserved in the animal host. Thus, to a large extent, the SCID mouse model mimics the dissemination pattern of Hodgkin's disease in man. To evaluate the role of adhesion molecule expression in the dissemination of HD-derived cell lines, CD44 and members of the immunoglobulin, integrin, selectin, and Fc receptor families were quantified by flow cytometry. CD30 expression was also measured. Although CD44 expression has been correlated with dissemination in non-Hodgkin's lymphoma (NHL), this was not the case in the Hodgkin's SCID mouse model. CD44 was not expressed on the disseminating cell lines L540 and L540cy but was expressed in the nondisseminating lines L428 and KM-H2.

Animals↗
PubMed1994

Correlation of cytogenetic findings with clinical features in 18 patients with inv(3)(q21q26) or t(3;3)(q21;q26).

An inversion in the long arm of chromosome 3--inv(3)(q21q26)--or a translocation between both homologous chromosomes 3--t(3;3)(q21;q26)--is found specifically in myeloid neoplasias characterized by disturbances of thrombopoiesis and megakaryocyte development. Cytogenetic findings were correlated with clinical and hematological data in altogether 18 patients with acute nonlymphocytic leukemia (ANLL) and with inv(3) (13 patients) or t(3;3) (five patients), six of whom were male and 12 who were female. Chromosomal changes in addition to the 3q anomalies were demonstrated in 14 out of 18 patients, predominantly numerical and structural aberrations of chromosome 7 (12 cases) and/or abnormalities of 5q (five cases). Complex karyotype abnormalities were observed in six of 13 patients with inv(3), but in only one of five patients with t(3;3). In ten out of our 18 patients a preceding myelodysplastic syndrome (MDS) and/or exposure to mutagenic/carcinogenic agents had been established. In eight patients the morphology of ANLL blasts was immature (FAB subtype M1); in three patients ANLL-M4, and in two patients each ANLL-M5, M6, and M7 was diagnosed; in one patient with antecedent MDS the leukemic blasts were not classifiable according to the FAB criteria. A disturbed megakaryocyte development, characterized by an excess of micromegakaryocytes was observed in 14 patients, seven of them showed normal or elevated platelet counts as an unusual feature in patients with ANLL. The clinical course and outcome was extremely poor: 15 of 18 patients died within 10 months after the diagnosis of ANLL. Because of their missing response to conventional chemotherapy, patients with inv(3) or t(3;3) have to be estimated as at high risk. The characterization of genes affected by inv(3) or t(3;3) could help to elucidate molecular changes leading to impaired proliferation and differentiation of hematopoietic cells, also of the megakaryocytic lineage. Based on molecular genetic findings new therapeutical approaches could be designed.

Adult↗
PubMed1993

Hodgkin's lymphoma-derived tissue serially transplanted into severe combined immunodeficient mice.

Hodgkin (H) and Reed-Sternberg (RS) cells are considered to be the malignant cell population in Hodgkin's disease (HD). To date, their analysis has been hampered by their scarcity in primary tumors, poor growth in vitro, and lack of an animal model. To establish an in vivo system for the characterization of the malignant cells in HD, tumor biopsy samples from 13 HD patients were transplanted beneath the renal capsule or into the liver of severe combined immunodeficient (SCID) mice. HD-derived tissue from three patients gave rise to human tumors in SCID mice. Three different histologic patterns were observed: (1) lymphoproliferative disease (LPD), (2) anaplastic large cell lymphoma (ALCL), (3) Hodgkin-like lesions (HDLL). Immunohistochemical analysis showed that the tumors consisted of activated B cells (CD30+, CD20+). Epstein-Barr virus (EBV)-encoded transcripts were found in 80% to 100% of the tumor cells, although H and RS cells in the primary tumors of two patients were EBV-. All tumors examined (3 of 3) and the majority (6 of 10) of cell lines recultured in vitro had an abnormal karyotype. Southern blot analysis of the human Ig heavy chain gene showed that monoclonal or oligoclonal tumors of different B-cell origin grew in the SCID mice from the same germ line-configurated primary biopsy specimen. Our data suggest that the human cells in the SCID mice have either been derived from EBV superinfected H and RS cells or from EBV-infected bystander cells. If the latter is true, then these bystander cells must be genetically abnormal. The genetic defect would be either aneuploidy or instable euploidy. In either case, the cells might proliferate into malignant aneuploid HDLL or ALCL under the influence of EBV and the special environment encountered in the SCID mice.

Adult↗
PubMed1993

Regional sublocalization of the human CD69 gene to chromosome bands 12p12.3-p13.2, the predicted region of the human natural killer cell gene complex.

The early activation antigen CD69 is a member of a supergene family of type II integral membrane proteins with a C-type lectin domain. In recent reports the genes encoding the natural killer (NK) cell-related molecules of this supergene family, NKR-P1, NK1.1 and Ly-49, were shown to be clustered in a chromosomal region in mouse, termed the NK gene complex. The human homologue of this complex is likely to reside on chromosome 12 near the PRP locus (12p13.2). By analyzing T cell hybrids, the CD69 gene was previously mapped to human chromosome 12. Here we report the regional sublocalization of the human CD69 gene to chromosome bands 12p12.3-p13.2, suggesting that CD69 belongs to one linkage group together with different cell surface molecules on NK cells.

Animals↗
PubMed1993

Clinical aspects of acute myeloid leukemias of the FAB types M3 and M4Eo. The AML Cooperative Group.

Acute promyelocytic leukemia (AML FAB M3, APL) and acute myelomonocytic leukemia with abnormal eosinophils (AML M4Eo) are considered distinct entities with characteristic clinical, morphological, cytogenetic, and prognostic features. Promyelocytic leukemia is characterized by abnormal promyelocytes replacing normal hematopoiesis associated with a translocation between the long arms of chromosomes 15 and 17 t (15; 17), severe coagulopathy, and responsiveness to all-trans retinoic acid (tretinoin). Characteristic features of AML M4Eo are a myelomonocytic marrow infiltration, eosinophils with abnormal immature granules positive for chloroacetate esterase, an inversion or translocation of chromosome 16, and an increased risk of meningeal relapses. Prognosis of both types of AML has been reported to be better than prognosis of the other entities combined. Since most of the published data were collected from heterogeneous patient populations treated with various chemotherapeutic regimens, we have analyzed treatment outcome of AML M3 and M4Eo in the AMLCG-85 study for patients younger than 60 years. For the total population of 594 patients of this study, CR rate was 68.89%, early death rate 11.60%, and no or partial remission was achieved in 19.51% of the cases. Of 40 patients with AML M3 or M3 v complete remission was attained in 62.5%. Nine patients died within 42 days after the start of antileukemic therapy (22.5%). Of these nine, four died because of infection, five because of bleeding. Relapse-free survival rate was 59% after 3 years, significantly better than the respective curve of the other FAB types combined (35% after 3 years). In AML M4Eo, 91.7% of the 24 patients reached complete remission. The early death rate was 8.3%. No case of nonresponse was seen. Relapse-free survival rate was 49% after 3 years compared with 35% for the other types combined.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1993

Molecular characteristics of HGF-SF and its role in cell motility and invasion.

Scatter factor (SF), a secretory protein of fibroblasts, dissociates and increases the motility of epithelial cells and may be involved in cell migration processes during embryogenesis and tumor progression. Hepatocyte growth factor (HGF) is a potent mitogen for hepatocytes and other cells, and is thought to play a role in liver regeneration. We have presented structural and functional evidence that human SF and human HGF are identical proteins encoded by a single gene, since (i) no differences could be found by protein sequencing, by cDNA analysis, or by immunological comparison, and (ii) SF acts as a hepatocyte growth factor--i.e., stimulates DNA synthesis of primary hepatocytes and is a morphogen of kidney epithelial cells--whereas HGF exhibits SF activity--i.e., dissociates and induces invasiveness of various epithelial cells. Furthermore, there exists only one gene for human HGF-SF which is located on chromosome 7, bands q11.2-21 (Weidner et al., Proc. Natl. Acad. Sci. USA 88, 7001-7005, 1991). HGF-SF has been found to be the ligand of the c-met receptor tyrosine kinase (Naldini et al., EMBO J. 10, 2867-2878, 1991b). We have recently used transient expression of naturally occurring and in vitro mutagenized cDNAs of HGF-SF in order to delineate the protein domains necessary for biological activity and c-met receptor activation. (i) A single-chain HGF-SF resulting from the destruction of the protease cleavage site between heavy and light chain (Arg494 to Gln) was largely inactive, indicating that proteolytic cleavage is essential for acquisition of the biologically active conformation. (ii) A HGF-SF splice variant encoding a protein with a 5 amino acid deletion in the first kringle domain was as highly active as the wild type molecule. (iii) The separately expressed light chain (with serine protease homology) was inactive in all assays tested. (iv) The separate heavy chain as well as a naturally occurring splice variant consisting of the N-terminus and the first two kringle domains bound the met receptor, stimulated its tyrosine phosphorylation, and induced dissociation of epithelial cells but not mitogenesis. These data indicate that a functional domain in the N-terminal region and/or the first two kringle domains of HGF-SF is sufficient for binding to and activation of the met receptor (Hartmann et al., Proc. Natl. Acad. Sci. USA, in press).

Animals↗
PubMed1993

Translocation t(1;22) mimicking t(1;19) in a child with acute lymphoblastic leukemia as revealed by chromosome painting.

The karyotype of a boy with acute lymphoblastic leukemia (ALL) presenting with numerical and structural chromosome aberrations as determined by Giemsa-banding was further investigated using chromosome painting (CP). A translocation t(11;18)(q23;q21) was verified by this approach, and gain of chromosome 21 material due to a structural rearrangement was detected. Moreover, an unbalanced translocation of the long arm of chromosome 1, resembling the well known translocation t(1;19), was demonstrated to involve chromosome 22 instead of chromosome 19. Immunophenotyping of the leukemic blasts led to the diagnosis common ALL (CD19+, CD10+, clg-). Our case indicates that in ALL a translocation t(1;19) may be mimicked by other chromosomal rearrangements, and that CP may efficiently complement conventional cytogenetics in the exact characterization of the involved chromosomes.

Child↗
PubMed1992

Growth of Hodgkin cell lines in severely combined immunodeficient mice.

No animal model exists for the in vivo growth of Hodgkin's-lymphoma-derived cells. Neither unmanipulated Hodgkin's-disease(HD)-derived cell lines nor primary biopsy tissue could be grown in nude mice. Since the severe combined immunodeficient (SCID) mouse has been reported to be a better recipient for transplanted human lymphatic tissue than the nude mouse, we tested whether SCID mice provide suitable conditions for the in vivo growth of HD cell lines. Tumorigenicity of HD cells was tested in untreated and pre-treated SCID mice and in another combined immunodeficient mouse strain, beige/nude/X-linked immunodeficient (BNX) mouse. SCID mice supported in vivo growth of the 6 HD cell lines tested (L428, L540, L591, DEV, HD-LM2, KM-H2). Only one of the 6 lines (DEV) was tumorigenic in BNX mice. No HD cell line proliferated in T-cell-deficient nude mice. Thus, in vivo growth of HD cell lines appeared to be related to the degree of host immunodeficiency. Additional growth supportive treatments such as fibrosarcoma co-transplantation, intraperitoneal mineral oil injection or immunosuppressive pre-treatment (anti-asialo-GMI-antibody injection) permitted growth of 3 additional HD cell lines in BNX mice. The immunophenotype and karyotype of explanted graft cells were identical to the original cell lines. Our experiments describe an effective and reproducible xenograft model for growth of Hodgkin's-disease-derived cell lines. This may be of value for elucidating the growth characteristics of Hodgkin's-lymphoma-derived cells as well as for testing new therapeutic regimens.

Animals↗
PubMed1992

The translocation (6;9) (p23;q34) shows consistent rearrangement of two genes and defines a myeloproliferative disorder with specific clinical features.

Translocation (6;9)(p23;q34) is a cytogenetic aberration that can be found in specific subtypes of both acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS). This translocation is associated with an unfavourable prognosis. Recently, the genes involved in the t(6;9) were isolated and characterized. Breakpoints in both the dek gene on chromosome 6 and the can gene on chromosome 9 appear to occur in defined regions, which allows us to diagnose this type of leukemia at the molecular level. Moreover, because of the translocation a chimeric dek-can mRNA is formed which, as we show here, is an additional target for diagnosis via cDNA-preparation and the polymerase chain reaction (PCR). We studied 17 patients whose blood cells and/or bone marrow cells showed a t(6;9) with karyotypic analysis. Fourteen patients suffered from AML, one patient had a refractory anemia with excess of blasts in transformation (RAEBt), one patient had an acute myelofibrosis (AMF), and one patient a chronic myeloid leukemia (CML). In nine cases studies at the DNA and RNA levels were possible while in seven cases only the DNA could be analyzed. In one case only RNA was available. Conventional Southern blot analysis showed the presence of rearrangements of both the dek gene and the can gene. In both genes, breakpoints cluster in one intron in the patients investigated. The presence of a consistent chimeric dek-can product after cDNA preparation followed by the PCR was demonstrated. We conclude from our data that the t(6;9) is found in myeloproliferative disorders with typical clinical characteristics. This translocation results in highly consistent abnormalities at the molecular level.

Adolescent↗
PubMed1992

T-cell receptor gamma/delta expressing acute leukemia emerging from sideroblastic anemia: morphological, immunological, and cytogenetic features.

Striking numerical and structural chromosome abnormalities (-Y, +8, i(7q), del (10)(q24), and del (11)(q21)) were detected by cytogenetic analysis in a patient's bone marrow with morphological features of both acute lymphoblastic leukemia and myelodysplastic disorder. Surface marker analysis characterized blast cells to be CD2+ CD7+ CD3+ CD4- CD8- expressing gamma/delta-T-cell receptor antigen and coexpressing CD11b and CD16. Exhibiting an identical phenotype as the leukemic cells, a prominent gamma/delta-TCR+ lymphocyte population was found in the bone marrow as well as in the peripheral blood. Cells of the latter compartment coexpressed CD56 and HLA-DR antigens and exhibited nonspecific cytotoxic activity. In the bone marrow cells NSCA could be induced after stimulation with interleukin 2 in vitro. Morphological, immunological, and cytogenetic findings suggest that gamma/delta-T-ALL emerged from a myelodysplastic disorder after sequential steps of malignant transformation. Leukemic cells with "mixed lineage" character may provide evidence for a common progenitor cell in the bone marrow. Assuming that the leukemic cells represent the malignant counterpart of normal CD3+ gamma/delta-TCR+ cells the results may contribute to our understanding of the origin and differentiation as well as the possible steps of malignant transformation of a gamma/delta-TCR+ lymphocyte population.

Anemia, Sideroblastic↗
PubMed1992

Preliminary report: growth of Hodgkin's lymphoma derived cells in immune compromised mice.

Until now there has been no satisfactory animal host for the in vivo growth of Hodgkin lymphoma cells. With the exception of one mutant subline (L540Cy) none of the other Hodgkin derived cell lines nor Hodgkin's disease (HD) derived lymphatic tissue could be propagated in suitable animal systems such as the T-cell deficient nude mouse. Recently, the severe combined immunodeficient (SCID-) mouse has been demonstrated as a possible recipient for human lymphatic tissue. In the present study, we have evaluated the SCID mouse as a possible in vivo model for Hodgkin's lymphoma. I) We demonstrate that seven permanent cell lines derived from patients with Hodgkin's disease grow progressively in SCID mice after subcutaneous and intraperitoneal inoculation. II) In addition, after intravenous injection, two of these lines (L540, L540Cy) show a disseminated growth pattern resembling the distribution of HD cells in man (involvement of lymph nodes, liver and bone marrow but not of spleen). The observed reproducible disseminated tumor growth establishes the SCID mouse as a new animal model for experimental treatment strategies in Hodgkin's lymphoma. III) We present preliminary results of the transplantation of primary material from 13 patients with Hodgkin's disease. Material from two patients induced human tumors in the SCID mice recipients, whereas material from two others led to the induction of mouse lymphomas. The human tumors showed three distinct histological patterns: 1) Lymphoproliferative disease (LPD); 2) anaplastic large cell lymphomas (ALCL); 3) Hodgkin like lesions (HLL). In vitro cell lines established from human SCID mouse tumors were of B-lymphoid origin, were EBV-positive and showed numerical and some structural chromosomal aberrations of varying degree.

Animals↗